Publications by authors named "Mao Jia"

37 Publications

Upper-Critical-Solution-Temperature Polymer Modified Gold Nanorods for Laser Controlled Drug Release and Enhanced Anti-Tumour Therapy.

Front Pharmacol 2021 23;12:738630. Epub 2021 Sep 23.

Department of Biliary Surgery, West China Hospital of Sichuan University, Chengdu, China.

Photothermal therapy (PTT) has become effective method for the treatment of malignant cancer. The development of PTT system with high anti-tumour effect is still the feasible research direction. Here, a new type of gold nanorods (AuNRs)-doxorubicin (DOX)/mPEG-peptide/P(AAm-co-AN) (APP-DOX) nano drug delivery system was proposed. Among them, AuNRs was used as high-efficiency photothermal agent. APP-DOX had a suitable size and can be targeted to accumulate in tumour tissues through circulation in the body. The abundant matrix metalloproteinase 2 (MMP-2) in the tumour environment intercepted and cut off the short peptide chain structure grafted on APP-DOX. At the same time, the removal of the PEG segment leaded to an increase in the hydrophobic properties of the system. Nanoparticles aggregated into large particles, causing them to stay and aggregate further at the tumour site. When irradiated by 808 nm near-infrared laser, APP-DOX achieved a gradual heating process. High temperature can effectively ablate tumours and enable UCST polymer to achieve phase transition, resulting in more anti-cancer drugs loaded in the polymer layer DOX was released, effectively killing cancer cells. Animal experiments had verified the possibility of the nano drug-carrying system and good tumour treatment effect. What's more worth mentioning is that compared with free DOX, the nano drug delivery system had lower biological toxicity and not cause obvious harmful effects on normal organs and tissues.
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http://dx.doi.org/10.3389/fphar.2021.738630DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8495017PMC
September 2021

Prevalence of dental caries in the first permanent molar and associated risk factors among sixth-grade students in São Tomé Island.

BMC Oral Health 2021 09 28;21(1):483. Epub 2021 Sep 28.

Ministry of Health, Água Grand, São Tomé and Príncipe.

Background: Dental caries is one of the most preventable oral diseases among children in developing countries. This study aims to estimate the prevalence and severity of dental caries in the first permanent molar and analyze the related risk factors among sixth-grade students in São Tomé Island.

Methods: A cross-sectional study with a stratified cluster sampling method was conducted on 1855 sixth-grade school children, mainly aged 11 to 14 years old, from 10 schools in 6 regions of São Tomé Island, from April 17 to June 27, 2021. Dental caries examination was performed by using the CAST criteria (DMFT) index, and the self-administered questionnaires about family background, oral hygiene, and relevant behaviors were collected. Multivariable logistic regression was used to study risk factors related to dental caries of the first permanent molar, and all data analyses were done using SPSS version 25.

Results: The prevalence of dental caries in the first permanent molar was 68.79%, without significant difference between gender, age, residence, and whether only child or not. The mean Decayed, Missing, and Filled Teeth (DMFT) index and mean Decayed, Missing, and Filled Surface (DMFS) index were 1.751 ± 1.514 and 3.542 ± 3.941, respectively. The rate of filling teeth was 5.50%, and Pit and Fissure Sealant (PFS) rate was 2.21%. The overall prevalence and DMFT index of dental caries of permanent teeth was 76.01% and 2.753 ± 4.569, respectively. The results of logistic regression analysis indicated that the frequency of candy/chocolate consumption (OR = 1.095) and fair self-assessment of dental health (OR = 1.354) were significantly associated with dental caries (P < 0.05).

Conclusions: The high prevalence of dental caries in the first permanent molar was a public health issue among sixth-grade school children in São Tomé Island. The prevalence of dental caries, mean DMFT and DMFS scores were higher, while the rate of filling and PFS teeth were lower than the average score of other African countries. Thus, oral health education, implement oral health preaching to school children and their parents is crucial to prevent dental caries.
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http://dx.doi.org/10.1186/s12903-021-01846-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8479893PMC
September 2021

Site selection of straw collection and storage facilities considering carbon emission reduction.

Environ Sci Pollut Res Int 2021 Jul 27. Epub 2021 Jul 27.

School of Transportation, Jilin University, Changchun, 130025, China.

Straw recycling has generated high collection and transportation costs. Scientifically informed collection, storage, and transportation methods can reduce automobile exhaust emissions and high transportation costs. According to the relevant statistics, China's total theoretical straw resources reached 920 million tons in 2020. Due to such regional and seasonal straw surpluses, however, comprehensive utilization technologies need to be improved, and farmers' awareness of environmental protection needs to be strengthened. In some areas, open burning of straw is still practiced, causing environmental pollution and wasting resources. This study used cost and carbon emission metrics in a dual-objective planning model to plan the site selection of straw collection and storage facilities. Compared with the current manual calculation in various links in straw supply logistics, modeling can resolve the contradiction between cost and carbon emission considerations and can help meet the goal of Pareto optimum while ensuring supply, reducing costs for enterprises, and providing decision-making assistance for the government. This paper uses transportation theory and a dual-objective, mixed-integer model to study the field of biomass energy. Through the planning and design of the biomass raw material supply chain, the system efficiency is improved, and the studied company can obtain more profits. This article also explores the role of controlling carbon emissions in the field of biomass energy. It is believed that the government not only needs to guide corporate decision-making by charging carbon taxes but also needs to support enterprises in participating in the field of biomass power generation through active policy guidance.
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http://dx.doi.org/10.1007/s11356-021-15581-zDOI Listing
July 2021

Identifying a Serum Exosomal-Associated lncRNA/circRNA-miRNA-mRNA Network in Coronary Heart Disease.

Cardiol Res Pract 2021 23;2021:6682183. Epub 2021 Jun 23.

Department of Geriatric Medicine, The Affiliated Jiangning Hospital with Nanjing Medical University, Nanjing 211100, Jiangsu, China.

Background: Accumulating evidence supports the importance of noncoding RNAs and exosomes in coronary heart disease (CHD). However, exosomal-associated competing endogenous RNA- (ceRNA-) mediated regulatory mechanisms in CHD are largely unexplored. The present study aimed to explore exosomal-associated ceRNA networks in CHD.

Methods: Data from 6 CHD patients and 32 normal controls were downloaded from the ExoRBase database. CHD and normal controls were compared by screening differentially expressed mRNAs (DEMs), lncRNAs (DELs), and circRNAs (DECs) in serum exosomes. MicroRNAs (miRNAs) targeting DEMs were predicted using the Targetscan and miRanda databases, and miRNAs targeted by DELs and DECs were predicted using the miRcode and starBase databases, respectively. The biological functions and related signaling pathways of DEMs were analyzed using the David and KOBAS databases. Subsequently, a protein-protein interaction (PPI) network was established to screen out on which hub genes enrichment analyses should be performed, and a ceRNA network (lncRNA/circRNA-miRNA-mRNA) was constructed to elucidate ceRNA axes in CHD.

Results: A total of 312 DEMs, 43 DELs, and 85 DECs were identified between CHD patients and normal controls. Functional enrichment analysis showed that DEMs were significantly enriched in "chromatin silencing at rDNA," "telomere organization," and "negative regulation of gene expression, epigenetic." PPI network analysis showed that 25 hub DEMs were closely related to CHD, of which ubiquitin C (UBC) was the most important. Hub genes were mainly enriched in "cellular protein metabolic process" functions. The exosomal-associated ceRNA regulatory network incorporated 48 DEMs, 73 predicted miRNAs, 10 DELs, and 15 DECs. The LncRNA/circRNA-miRNA-mRNA interaction axes (RPL7AP11/hsa-miR-17-5p/UBC and RPL7AP11/hsa-miR-20b-5p/UBC) were obtained from the network.

Conclusions: Our findings provide a novel perspective on the potential role of exosomal-associated ceRNA network regulation of the pathogenesis of CHD.
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http://dx.doi.org/10.1155/2021/6682183DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8249161PMC
June 2021

An unusual high ozone event over the North and Northeast China during the record-breaking summer in 2018.

J Environ Sci (China) 2021 Jun 23;104:264-276. Epub 2020 Dec 23.

State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), Institute id Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; University of the Chinese Academy of Sciences, Beijing 100049, China.

Under the background of global warming, the summer temperature of the North and Northeast China (NNEC) has significantly increased since 2017, which was accompanied by the aggravated ozone (O) pollution. In 2018, the NNEC experienced a record-breaking summer of the past 40 years. Influenced by the abnormal high temperatures, a regional ozone event occurred on 2-3 August, over 63% of 79 selected cities in the NNEC were exposed to O pollution, and the maximum value of MDA8 O reached 268 μg/m. Observations indicated that ozone concentrations agree well with the maximum temperature at 2 meters (MT2M) over NNEC with a correlation coefficient of 0.69. During the pollution episode, strong downdraft in the local high (35°N-42.5°N, 112.5°E-132.5°E; LH) over the NNEC created the favourable meteorological conditions for O formation. By analyzing the horizontal wind and wave activity fluxes (WAFs) at 200 hPa, we found that the LH formation was resulted from the Rossby wave propagation from upstream along the mid-latitude Asian jet. The split polar vortex intrusion further strengthened the amplitude of the Rossby wave and reinforced the LH. Moreover, a secondary circulation between Typhoon Jongdari and the LH contributed to the enhanced LH with strong subsidence. On the other hand, the stratospheric intrusions under the deep subsidence also contributed to the enhanced surface O. In this study, the deep-seated meteorological dynamical mechanisms contributing to the abnormal high temperatures were investigated, which can lead to a better understanding of the regional O pollution over NNEC under the global-warming background.
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http://dx.doi.org/10.1016/j.jes.2020.11.030DOI Listing
June 2021

A Comprehensive Review of Cholinesterase Modeling and Simulation.

Biomolecules 2021 04 15;11(4). Epub 2021 Apr 15.

Department of Chemistry & Biochemistry, California State University, Long Beach, CA 90840, USA.

The present article reviews published efforts to study acetylcholinesterase and butyrylcholinesterase structure and function using computer-based modeling and simulation techniques. Structures and models of both enzymes from various organisms, including rays, mice, and humans, are discussed to highlight key structural similarities in the active site gorges of the two enzymes, such as flexibility, binding site location, and function, as well as differences, such as gorge volume and binding site residue composition. Catalytic studies are also described, with an emphasis on the mechanism of acetylcholine hydrolysis by each enzyme and novel mutants that increase catalytic efficiency. The inhibitory activities of myriad compounds have been computationally assessed, primarily through Monte Carlo-based docking calculations and molecular dynamics simulations. Pharmaceutical compounds examined herein include FDA-approved therapeutics and their derivatives, as well as several other prescription drug derivatives. Cholinesterase interactions with both narcotics and organophosphate compounds are discussed, with the latter focusing primarily on molecular recognition studies of potential therapeutic value and on improving our understanding of the reactivation of cholinesterases that are bound to toxins. This review also explores the inhibitory properties of several other organic and biological moieties, as well as advancements in virtual screening methodologies with respect to these enzymes.
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http://dx.doi.org/10.3390/biom11040580DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8071298PMC
April 2021

Facile Fabrication of Flexible Pressure Sensor with Programmable Lattice Structure.

ACS Appl Mater Interfaces 2021 Mar 19;13(8):10388-10396. Epub 2021 Feb 19.

New Materials Institute, Department of Mechanical, Materials and Manufacturing Engineering, University of Nottingham Ningbo China, Ningbo 315100, China.

Flexible pressure sensors have attracted intense attention because of their widespread applications in electronic skin, human-machine interfaces, and healthcare monitoring. Conductive porous structures are always utilized as active layers to improve the sensor sensitivities. However, flexible pressure sensors derived from traditional foaming techniques have limited structure designability. Besides, random pore distribution causes difference in structure and signal repeatability between different samples even in one batch, therefore limiting the batch production capabilities. Herein, we introduce a structure designable lattice structure pressure sensor (LPS) produced by bottom-up digital light processing (DLP) 3D printing technique, which is capable of efficiently producing 55 high fidelity lattice structure models in 30 min. The LPS shows high sensitivity (1.02 kPa) with superior linearity over a wide pressure range (0.7 Pa to 160 kPa). By adjusting the design parameters such as lattice type and layer thickness, the electrical sensitivities and mechanical properties of LPS can be accurately controlled. In addition, the LPS endures up to 60000 compression cycles (at 10 kPa) without any obvious electrical signal degradation. This benefits from the firm carbon nanotubes (CNTs) coating derived from high-energy ultrasonic probe and the subsequent thermal curing process of UV-heat dual-curing photocurable resin. For practical applications, the LPS is used for real time pulse monitoring, voice recognition and Morse code communication. Furthermore, the LPS is also integrated to make a flexible 4 × 4 sensor arrays for detecting spatial pressure distribution and a flexible insole for foot pressure monitoring.
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http://dx.doi.org/10.1021/acsami.0c21407DOI Listing
March 2021

Disassembly sequence planning of waste auto parts.

J Air Waste Manag Assoc 2021 05 8;71(5):607-619. Epub 2021 Feb 8.

College of New Energy and Environment, Jilin University, Changchun, Jilin, People's Republic of China.

The disassembly of used products is a critical procedure in remanufacturing, and different disassembly strategies are often obtained from different perspectives. To describe the disassembly process more accurately, the uncertainty of the information in the disassembly process should be considered. Therefore, random variables are introduced for disassembly time, cost, and effort. Based on the extended stochastic Petri net modeling method and stochastic programming theory, a stochastic optimization algorithm combined with artificial intelligence technology and a multiobjective genetic algorithm are designed, and a multiobjective optimization model for the disassembly sequence of used car parts under uncertain conditions is successfully constructed. This model considers the viewpoint of the decision maker. Moreover, the Monte Carlo method is applied to solve the multiobjective optimization model, and the validity and practicability of the model are verified by an example of an automotive transmission.: With the rapid development of the economy and the shortening of the product life cycle, the rate of product renewal is getting faster and faster, which also leads to the production of a large number of waste products. According to the forecast of the relevant departments, it is estimated that, in 2020, there will be about 35 million used televisions, 15 million used refrigerators, 13 million used washing machines, 12 million used air conditioners, 57 million used computers, and 8.3 million scrapped cars. Waste products contain a lot of renewable resources. If they cannot be effectively recycled, it will be a great waste of resources, and unreasonable disposal of waste products may have a negative impact on the environment. Therefore, due to environmental pressure and economic drive, product recycling and remanufacturing activities have caused widespread concern in society. Disassembly is defined as the operation or activity of disassembling an assembly such as a product, assembly, or component, and is the result of multiple removal operations of the product. It is a prerequisite for the efficient recycling of products and the first link in remanufacturing, that is, disassembly as a new production activity, which can provide raw materials for the smooth progress of the remanufacturing production plan, namely, old rough or used parts. Efficient dismantling not only saves natural resources and energy, but also effectively reduces environmental pollution. It is also an important guarantee for promoting the healthy development of the circular economy and achieving sustainable industrial development. The length of time required for the dismantling process, the level of costs, and the amount of profits obtained will directly affect the economic benefits of the recycling of end-of-life products. Therefore, the evaluation and optimization of the dismantling process of waste products have become one of the current hot issues. The research on the dismantling of waste products is conducive to speeding up the recycling process of waste, to a greater extent, the rapid and full recovery of resources, and to a certain extent, it will provide value basis and theoretical significance for subsequent research.
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http://dx.doi.org/10.1080/10962247.2020.1871444DOI Listing
May 2021

Meteorological mechanism for a large-scale persistent severe ozone pollution event over eastern China in 2017.

J Environ Sci (China) 2020 Jun 27;92:187-199. Epub 2020 Feb 27.

State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; University of Chinese Academy of Sciences, Beijing, 100049, China.

An intensive and persistent regional ozone pollution event occurred over eastern China from 25 June to 5 July 2017. 73 out of 96 selected cities, most located in the Beijing-Tianjin-Hebei and the surrounding area (BTHS), suffered severe ozone pollution. A north-south contrast ozone distribution, with higher ozone (199 ± 33 μg/m) in the BTHS and lower ozone (118 ± 25 μg/m) in the Yangtze River Delta (YRD), was found to be dominated by the position of the West Pacific Subtropical High (WPSH) and mid-high latitude wave activities. In the BTHS, the positive anomalies of geopotential height at 500 hPa and temperature at the surface indicated favorable meteorological conditions for local ozone formation. Prevailing northwesterly winds in the mid-high troposphere and warm advection induced by weak southerly winds in the low troposphere resulted in low-moderate relative humidity (RH), less total cloud cover (TCC), strong solar radiation and high temperatures. Moreover, southerly winds prevailing over the BTHS aggravated the pollution due to regional transportation of O and its precursors. On one hand, the deep sinking motion and inversion layer suppressed the dispersion of pollutants. On the other hand, O-rich air in the upper layer was maintained at night due to temperature inversion, which facilitated O vertical transport to the surface in the next-day morning due to elevated convection. Generally, temperature, UV radiation, and RH showed good correlations with O in the BTHS, with rates of 8.51 (μg/m)/°C (within the temperature range of 20-38°C), 59.54 (μg/m)/(MJ/m) and -1.93 (μg/m)/%, respectively.
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http://dx.doi.org/10.1016/j.jes.2020.02.019DOI Listing
June 2020

Highly time-resolved chemical characterization and implications of regional transport for submicron aerosols in the North China Plain.

Sci Total Environ 2020 Feb 28;705:135803. Epub 2019 Nov 28.

State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China. Electronic address:

To investigate the regional transport and formation mechanisms of submicron aerosols in the North China Plan (NCP), for the first time, we conducted simultaneous combined observations of the non-refractory submicron aerosols (NR-PM) chemical compositions using aerosol mass spectrometer at urban Beijing (BJ) and at regional background area of the NCP (XL), from November 2018 to January 2019. During the observation period, average mass concentrations of PM in BJ and XL were 26.6 ± 31.7 and 16.0 ± 18.7 μg m respectively. The aerosol composition in XL showed a lower contribution of organic aerosol (33% vs. 43%) and higher fractions of nitrate (35% vs. 30%), ammonium (16% vs. 13%), and chlorine (2% vs. 1%) than in BJ. Additionally, a higher contribution of secondary organic aerosol (SOA) was also observed in XL, suggesting low primary emissions and highly oxidized OA in the background area. Nitrate displayed a significantly enhanced contribution with the aggravation of aerosol pollution in both BJ and XL, which was completely neutralized by excess ammonium at both sites, suggesting that the abundant ammonia emissions in the NCP favor nitrate formation on a regional scale. In addition, a higher proportion of nitrate in XL can be attributed to the more neutral and higher oxidation capacity of the background atmosphere. Heterogeneous aqueous reaction plays an important role in sulfate and SOA formation, and is more efficient in BJ which can be attributed to the higher aerosol surface areas at urban site. Regional transport from the southwestern regions of NCP showed a significant impact on the formation of haze episodes. Beside the invasion of transported pollutants, the abundant water vapor associated with the air mass to the downwind background area further enhanced local secondary transformation and expanded the regional scope of the haze pollution in the NCP.
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http://dx.doi.org/10.1016/j.scitotenv.2019.135803DOI Listing
February 2020

Toxicological responses, bioaccumulation, and metabolic fate of triclosan in Chlamydomonas reinhardtii.

Environ Sci Pollut Res Int 2020 Apr 20;27(10):11246-11259. Epub 2020 Jan 20.

College of Food Science and Light Industry, Nanjing Tech University, Puzhu South Street No. 30, Nanjing, 211816, China.

Triclosan (TCS) is a broad-spectrum antimicrobial agent that is broadly used in personal care products. It has been shown to cause the contamination of a variety of aquatic environments. Since algae has been the primary producers of aquatic ecosystems, understanding the toxicological mechanisms and the metabolic fate of TCS is vital for assessing its risk in an aquatic environment. In our study, 0.5-4 mg L TCS treatments for 72 h in a culture of Chlamydomonas reinhardtii (C. reinhardtii) showed progressive inhibition of cell growth and reduced the chlorophyll content. The EC value of C. reinhardtii after 72 h was 1.637 mg L, which showed its higher level of resistance to TCS in comparison with other algal species. The exposure to TCS led to oxidative injuries of algae in relation to the increment of malonaldehyde content, cell membrane permeability, and HO levels. Furthermore, the oxidative stress from TCS stimulated a series of antioxidant enzyme activities and their gene expressions. Simultaneously, the accumulated TCS in C. reinhardtii arouses the detoxification/degradation-related enzymes and related gene transcriptions. In the medium, approximately 82% of TCS was removed by C. reinhardtii. Importantly, eight TCS metabolites were identified by ultra-performance liquid chromatography-high-resolution mass spectrometry and their relative abundances were measured in a time-course experiment. Six of these metabolites are reported here for the first time. The metabolic pathways of triclosan via C. reinhardtii including reductive dechlorination, hydroxylation, sulfhydrylation, and binding with thiol/cysteine/GSH/glycosyl were manifested to broaden our understanding of the environmental fate of TCS. Graphical Abstract.
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http://dx.doi.org/10.1007/s11356-020-07704-9DOI Listing
April 2020

A Review on the Partial and Complete Dissolution and Fractionation of Wood and Lignocelluloses Using Imidazolium Ionic Liquids.

Polymers (Basel) 2020 Jan 11;12(1). Epub 2020 Jan 11.

Department of Mechanical Engineering, Al-Ghurair University, Dubai International Academic City, Dubai P.O. Box 37374, UAE.

Ionic liquids have shown great potential in the last two decades as solvents, catalysts, reaction media, additives, lubricants, and in many applications such as electrochemical systems, hydrometallurgy, chromatography, CO capture, etc. As solvents, the unlimited combinations of cations and anions have given ionic liquids a remarkably wide range of solvation power covering a variety of organic and inorganic materials. Ionic liquids are also considered "green" solvents due to their negligible vapor pressure, which means no emission of volatile organic compounds. Due to these interesting properties, ionic liquids have been explored as promising solvents for the dissolution and fractionation of wood and cellulose for biofuel production, pulping, extraction of nanocellulose, and for processing all-wood and all-cellulose composites. This review describes, at first, the potential of ionic liquids and the impact of the cation/anion combination on their physiochemical properties and on their solvation power and selectivity to wood polymers. It also elaborates on how the dissolution conditions influence these parameters. It then discusses the different approaches, which are followed for the homogeneous and heterogeneous dissolution and fractionation of wood and cellulose using ionic liquids and categorize them based on the target application. It finally highlights the challenges of using ionic liquids for wood and cellulose dissolution and processing, including side reactions, viscosity, recyclability, and price.
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http://dx.doi.org/10.3390/polym12010195DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7023464PMC
January 2020

A novel strategy for selective removal and rapid collection of triclosan from aquatic environment using magnetic molecularly imprinted nano-polymers.

Chemosphere 2020 Jan 24;238:124640. Epub 2019 Aug 24.

College of Food Science and Light Industry, Nanjing Tech University, Nanjing, 211816, China. Electronic address:

Triclosan (TCS) is a kind of chronic toxicity to aquatic organisms. Due to its highly effective antimicrobial, TCS has been widely applied in personal-care products, which naturally poses a potential risk to the ecological system and human health since its release into water-ecological environment. Therefore, it urgently demands a selective, easily separated, recyclable, and low-cost adsorbent to remove the residues of TCS from aquatic environments. In this study, a novel magnetic molecularly imprinted nano-polymers (TMIPs) were prepared for selective adsorption and convenient collection of TCS in aquatic samples, based on a core-shell technique using TCS as template molecule and SiO-coated FeO nanoparticles as the support substrate. The functional groups, particle size, morphology and magnetic property of TMIPs were characterized by Fourier-transform infrared spectroscopy, scanning electron microscope, transmission electron microscopy and vibrating sample magnetometer, respectively. The obtained TMIPs possessed excellent adsorption capacity (Q = 53.12 mg g), speedy adsorption equilibrium time (2 min) and high selectivity (k' = 6.321) for TCS. Moreover, the pH-tolerance and stability tests manifested that the adsorption capacity of TMIPs for TCS was acid-resistance and could retain 94.2% of the maximum Q after 5 times removal-regeneration cycles. The feature of magnetically susceptibility can simplify the procedures of sample handling in TCS determination, because the TMIPs of TCS are easy to be recycled from aquatic samples. As an application demonstration, the toxicity test in microalgae confirmed that a tiny amount of TMIPs could significantly eliminate the toxic effect of TCS on Chlamydomonas reinhardtii via the efficient binding with TCS.
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http://dx.doi.org/10.1016/j.chemosphere.2019.124640DOI Listing
January 2020

A Review of the Surface Modification of Cellulose and Nanocellulose Using Aliphatic and Aromatic Mono- and Di-Isocyanates.

Molecules 2019 Jul 31;24(15). Epub 2019 Jul 31.

Fraunhofer Institute for Wood Research (WKI), Bienroder Weg 54E, 38108 Braunschweig, Germany.

Nanocellulose has been subjected to a wide range of chemical modifications towards increasing its potential in certain fields of interest. These modifications either modulated the chemistry of the nanocellulose itself or introduced certain functional groups onto its surface, which varied from simple molecules to polymers. Among many, aliphatic and aromatic mono- and di-isocyanates are a group of chemicals that have been used for a century to modify cellulose. Despite only being used recently with nanocellulose, they have shown great potential as surface modifiers and chemical linkers to graft certain functional chemicals and polymers onto the nanocellulose surface. This review discusses the modification of cellulose and nanocellulose using isocyanates including phenyl isocyanate (PI), octadecyl isocyanate (OI), toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), hexamethylene diisocyanate (HMDI), and their derivatives and polymers. It also presents the most commonly used nanocellulose modification strategies including their advantages and disadvantages. It finally discusses the challenges of using isocyanates, in general, for nanocellulose modification.
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http://dx.doi.org/10.3390/molecules24152782DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6695919PMC
July 2019

Synergistic Catalysis for Asymmetric [3 + 2] Cycloadditions of 2-Indolylmethanols with -Unsaturated Aldehydes.

J Org Chem 2019 09 14;84(17):11186-11194. Epub 2019 Aug 14.

School of Pharmacy and Shanghai Key Laboratory of New Drug Design , East China University of Science and Technology , 130 Meilong Road , Shanghai 200237 , People's Republic of China.

A catalytic asymmetric [3 + 2] cycloaddition of 2-indolylmethanols with -unsaturated aldehydes was developed for the first time. This transformation was achieved by a synergistic catalytic system consisting of a palladium complex, a Brønsted acid, and a chiral secondary amine to synthesize biologically active cyclopenta[]indole derivatives with excellent diastereo- and enantioselectivities (up to >20:1 dr, up to 99% ee).
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http://dx.doi.org/10.1021/acs.joc.9b01234DOI Listing
September 2019

Enantioselective Construction of Dihydropyrido[1,2-]indoles via Organocatalytic Arylmethylation of 2-Enals with Inert Aryl Methane Nucleophiles.

Org Lett 2019 07 28;21(14):5514-5518. Epub 2019 Jun 28.

School of Pharmacy and Shanghai Key Laboratory of New Drug Design , East China University of Science and Technology , 130 Meilong Road , Shanghai 200237 , China.

An organocatalytic asymmetric arylmethylation/-hemiacetalization of 2-indolyl methane derivatives and 2-enals was developed. Notably, the 2-methyl of indole was readily deprotonated to produce highly reactive nucleophilic species by introducing the nitro group at the C3 position of the indole ring. A spectrum of valuable chiral dihydropyrido[1,2-]indoles were efficiently constructed with excellent enantioselectivity (up to >99% ee). Furthermore, the corresponding products could be easily functionalized via simple deprotonation and treatment with other electrophiles with excellent diastereoselectivities (>20:1 dr).
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http://dx.doi.org/10.1021/acs.orglett.9b01837DOI Listing
July 2019

Application of Non-invasive Positive Pressure Ventilation Combined with PetCO₂ Monitoring for Patients with Chronic Obstructive Pulmonary Disease Combined with Severe Respiratory Failure.

J Coll Physicians Surg Pak 2019 Jun;29(6):545-548

Department of Emergency, The Affiliated Wuxi No.2 People's Hospital of Nanjing Medical University, Wuxi, China.

Objective: To investigate the role of PetCO₂ monitoring in non-invasive positive pressure ventilation (NPPV) treatment for chronic obstructive pulmonary disease (COPD) patients combined with severe respiratory failure.

Study Design: A clinical retrospective study.

Place And Duration Of Study: The ICU Emergency Department, Wuxi Second People's Hospital, Wuxi, China, from February 2015 to February 2016.

Methodology: A total of 60 COPD patients with respiratory failure were selected. All patients received non-invasive positive pressure ventilation and conventional treatment. PetCO₂ values were recorded two hours before and after NPPV treatment. At the same time, blood was collected for arterial blood gas analysis. Changes in PetCO₂, PaCO₂ and the difference between PaCO₂ and PetCO₂ (Pa-etCO₂) were also monitored to determine the correlation between PetCO₂ and PaCO₂.

Results: After two hours of initial NPPV treatment, among the 60 patients, the PaCO₂ and Pa-etCO₂ of 40 patients were significantly decreased (66.7%), the PaCO₂ and Pa-etCO₂ of 20 patients were not significantly decreased (33.3%). The correlation analysis revealed that PaCO₂ and PetCO₂ were negatively correlated (correlation coefficient r = -0.537, p=0.001, p<0.001). Furthermore, there were no significant correlations between PaCO₂ and PetCO₂ in the ineffective group (correlation coefficient r = -0.253, p=0.116, p>0.05).

Conclusion: PaCO₂ monitoring could not be replaced by PetCO₂ monitoring for patients with COPD combined with severe respiratory failure. Nevertheless, dynamic monitoring can instantly feedback the respiration state, which can guide the respiration, and improve the success rate of NPPV treatment and prognosis.
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http://dx.doi.org/10.29271/jcpsp.2019.06.545DOI Listing
June 2019

Preparation of core-shell magnetic molecularly imprinted polymer nanoparticle for the rapid and selective enrichment of trace diuron from complicated matrices.

Ecotoxicol Environ Saf 2019 Aug 8;177:66-76. Epub 2019 Apr 8.

College of Food and Light Industry, Nanjing Tech University, Puzhu South Street No.30, Nanjing, 211816, China.

A novel magnetic MIPs (DUMIPs) was prepared by surface molecular imprinting method using superparamagnetic core-shell nanoparticle ([email protected]) as the sacrificial support matrix, herbicide diuron as template, α-methacrylic acid as the functional monomer, trimethylolpropane trimethacrylate as the crosslinker, azobisisobutyronitrile as the initiator, and acetonitrile as the porogen. Highly cross-linked porous surface and excellent magnetic property were characterized by Fourier-transform infrared spectroscopy, transmission electron microscopy, and vibrating sample magnetometer, respectively. The adsorption capacity of DUMIPs was 8.1 mg g, 2.6-fold over its corresponding non-imprinted polymers (DUNIPs). The adsorption in DUMIPs was considered as multilayer adsorption and posed high affinity to diuron, due to the better fitting to Freundilich isotherm. Competitive recognition study demonstrated DUMIPs had highly selective binding diuron. DUMIPs, as an influential sorbent has been used for selective extraction of diuron from environmental samples (paddy field water, paddy soil and grain seedlings) and the elution was determined by high efficiency liquid chromatography (HPLC). In this analytical method, various factors affecting the extraction efficiency such as pH, sorbent dosage, utilization efficiency and volumes of eluent were simultaneously investigated. Under the optimal conditions, the linearity of the method obtained is in the range of 0.02-10.0 mg L. The limit of detection is 0.012 mg L. In four spiked levels (0.04, 0.2, 1.0, and 4.0 mg kg), the recoveries of diuron in real samples are in the range of 83.56%-116.10% with relative standard deviations in the range of 1.21-6.81%. Importantly, compared to C-SPE column, the MMIPs exhibited convenient separation by external magnetic field, strong clean-up capacity, and selective enrichment for diuron. Thus, the DUMIPs-based method is great potential for efficient sample preparation in the determination of trace amounts of diuron residues in complex matrices.
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http://dx.doi.org/10.1016/j.ecoenv.2019.03.117DOI Listing
August 2019

Differentiation of human amniotic epithelial cells into osteoblasts is induced by mechanical stretch via the Wnt/β‑catenin signalling pathway.

Mol Med Rep 2018 Dec 22;18(6):5717-5725. Epub 2018 Oct 22.

Department of Orthopedics, Yongchuan Hospital of Chongqing Medical University, Chongqing 402160, P.R. China.

Human amniotic epithelial cells (hAECs) have recently been recognized as a potential source of stem cells. The present study was designed to investigate the effects of mechanical stretch on the osteogenic differentiation of hAECs. As it has been previously reported that the physical environment is an important factor in maintaining the phenotype and functionality of differentiated cells, mechanical stretch was use to mimic the mechanical environment in the present study, with the following parameters: 5% elongation of the hAECs at a frequency of 0.5 Hz, with evaluation at 2, 6, 12 and 24 h time points. The osteogenic differentiation process of the hAECs followed by mechanical stimulation was evaluated by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR), western blotting and immunocytochemistry. Additionally, in a parallel study, a runt‑related transcription factor 2 (Runx2)/core binding factor α 1 (Cbfa1)‑specific short hairpin RNA (shRNA) plasmid vector and a scrambled shRNA control plasmid was constructed for transfection into the hAECs prior to mechanical stimulation. The cultured hAECs exhibited a cobblestone‑shaped epithelial‑like phenotype and were positive for stage‑specific embryonic antigen‑4, cytokeratin‑19, cluster of differentiation 44 and octamer‑binding protein 4, as detected by flow cytometry, western blotting or confocal microscopy. The qPCR and western blotting data demonstrated that the mRNA and protein expression levels of Runx2/Cbfa1, alkaline phosphatase and osteocalcin were upregulated compared with the control group following stretching and they peaked at 12 h. These results indicated that the osteogenic differentiation of the hAECs was induced by mechanical stimuli. Additionally, the mRNA and protein expression levels of β‑catenin and cyclin D were increased significantly following stretching; however, they were decreased following Runx2/Cbfa1‑shRNA transfection as observed by RT‑qPCR and western blotting. These results suggested that the Wnt/β‑catenin pathway may have an important role in mechanical stretch‑induced osteogenic differentiation of the hAECs. Furthermore, the combination of stretch and osteogenic induction medium had synergistic effects on the osteogenic differentiation. The results of the present study demonstrated that mechanical stimuli have an important role in osteogenic differentiation of hAECs via the Wnt/β‑catenin signalling pathway, which may be a potential therapeutic strategy in bone regenerative medicine.
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http://dx.doi.org/10.3892/mmr.2018.9571DOI Listing
December 2018

Residue determination of triclopyr and aminopyralid in pastures and soil by gas chromatography-electron capture detector: Dissipation pattern under open field conditions.

Ecotoxicol Environ Saf 2018 Jul 27;155:17-25. Epub 2018 Feb 27.

Institute of Agricultural Environment and Resource, Yunnan Academy of Agricultural Science, Beijing Road No. 2238, Panlong District, Yunnan 650205, China. Electronic address:

In this study, a new method for the simultaneous quantitative determination of triclopyr and aminopyralid in forage grass, hay, and soil was developed and validated using gas chromatography coupled with electron capture detector (GC-ECD). In this method, a simple and maneuverable esterification reaction was applied to convert the two acidic herbicides into their ester form with methanol. The target compounds were extracted with 1% hydrochloric acid-acetonitrile, esterified, purified by florisil solid-phase extraction cartridge, and detected in a single run by the GC-ECD. The average recoveries using this method, at different fortified levels, ranged from 80% to 104% with intra-day and inter-day RSDs in the range of 1.2-10.8% and 3.3-10.3% for both the herbicides, respectively. The LODs were below 0.02 mg/kg while the LOQs were below 0.05 mg/kg, both of which were much lower than the maximum residue limits (MRLs) of 25-700 mg/kg in pastures, as established by the USA (the code of federal regulations). The open field dissipation and residual analysis in pastures and soil were conducted with the commercial formulation at two locations. With time, both triclopyr and aminopyralid dissipated via first-order kinetics. In forage grass, both compounds degraded rapidly over the first 14- or 21-d period and at a slow rate over the remainder of experimental days. In soil, they degraded at a relatively slow rate, and dissipated steadily to below or close to the LOQ by 60-d post application. The half-lives of triclopyr were 1.4-1.8 d and 6.2-9.0 d and aminopyralid were 1.7-2.1 d and 8.2-10.6 d in terms of forage grass and soil, respectively. The terminal residue results indicated that on 7 d after the treatment, the residues of aminopyralid and triclopyr in forage grass and hay were lower than the MRLs set by the USA. This work can provide guidance on the reasonable use of these herbicides and also provide an analytical method for the determination of triclopyr and aminopyralid in pasture and soil.
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http://dx.doi.org/10.1016/j.ecoenv.2018.02.035DOI Listing
July 2018

Imidazole, a New Tunable Reagent for Producing Nanocellulose, Part I: Xylan-Coated CNCs and CNFs.

Polymers (Basel) 2017 Sep 27;9(10). Epub 2017 Sep 27.

Chair of Forest Biomaterials, Faculty of Environment and Natural Resources, Albert-Ludwig-University of Freiburg, Werthmannstr 6, 79085 Freiburg, Germany.

Imidazole is reported to be an effective reactant for the production of nanocellulose from hardwood pulp. The morphologies and surface properties of the nanocellulose can be simply tailored according to the water content in the imidazole system: with pure imidazole, cellulose nanofibrils (CNFs) in a yield of 10 wt % can be produced. With 25 wt % of water in imidazole, cellulose nanocrystals (CNCs) are obtained in 20 wt % yield. Both nanocelluloses exhibit crystallinity indices in the order of 70%. Interestingly, they retain the original xylan from the pulp with ca. 9⁻10 wt % of residual xylan content.
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http://dx.doi.org/10.3390/polym9100473DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6418970PMC
September 2017

Effects of Central Nervous System Drugs on Recovery After Stroke: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Clin Drug Investig 2017 Oct;37(10):901-928

Department of Pharmacy, Faculty of Science, National University of Singapore, 18 Science Drive 4, Singapore, 117543, Singapore.

Background And Objective: Pilot trials have suggested that pharmacotherapy may aid stroke recovery. The aim of this study was to systematically review the effects of antidepressants, anti-Alzheimer drugs, anti-Parkinson drugs, central nervous system (CNS) stimulants and piracetam on gross motor function, cognition, disability, dependency and quality of life (QOL) after stroke.

Methods: PubMed, EMBASE and the Cochrane Central Register of Controlled Trials databases were searched, and 44 randomized controlled trials that compared outcomes of interest between drug treatment and placebo or no treatment were included. For each study, standardized mean difference (SMD) or mean difference (MD) with 95% confidence interval (CI) were calculated. Meta-analyses were conducted to pool results using either the fixed-effects or random-effects model.

Results: Selective serotonin reuptake inhibitors (SSRIs) improved gross motor function (SMD 0.54, 95% CI 0.22-0.85; three studies), disability (SMD 0.49, 95% CI 0.32-0.66; 14 studies) and QOL (MD 6.46, 95% CI 4.71-8.22; two studies), but there was insufficient evidence for their use in enhancing global cognition (SMD 0.23, 95% CI -0.01 to 0.46; five studies) and dependency (risk ratio 0.81, 95% CI 0.68-0.97; one fluoxetine study). In particular, gross motor function was improved by fluoxetine (SMD 0.64, 95% CI 0.31-0.98; two studies), while disability was improved by paroxetine (SMD 1.05, 95% CI 0.63-1.46; two studies), citalopram (SMD 0.51, 95% CI 0.08-0.93; two studies) and fluoxetine (SMD 0.41, 95% CI 0.22-0.60; nine studies). There is insufficient evidence for the use of anti-Alzheimer drugs, anti-Parkinson drugs, CNS stimulants and piracetam to promote stroke recovery.

Conclusions: Administration of SSRIs may improve gross motor function, reduce disability and enhance QOL for patients recovering from stroke.
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http://dx.doi.org/10.1007/s40261-017-0558-4DOI Listing
October 2017

First Insight into the Molecular Epidemiology of Isolates from the Minority Enclaves of Southwestern China.

Biomed Res Int 2017 17;2017:2505172. Epub 2017 May 17.

Yunnan Provincial Center for Tuberculosis Research, Yunnan Provincial Center for Disease Control and Prevention, Kunming, China.

Yunnan is a province located in southwestern China. The aim of this study was to investigate the genetic diversity of (MTB) strains circulating in Yunnan Province. We used spoligotyping and a 12-locus high-resolution VNTR set to identify a total of 271 MTB isolates collected from six prefectures' Yunnan. All the 271 patients were classified as 11 different ethnic groups, including 133 Han patients (49.1%) and 138 minority patients (50.9%). Spoligotyping analyses revealed that the largest two spoligotypes were SIT1 (Beijing family, = 136) and SIT53 (T family, = 35). Statistical analysis indicated that the proportion of Beijing genotype in Qujing was significantly higher than that in the ethnic enclaves ( ≤ 0.01). Compared with the percentage of Beijing-family isolates from patients under 25 years of age (72.7%), those from patients aged 45~64 years (44.6%, < 0.01) and older than 64 years (48.1%) ( = 0.04) were significantly lower. Beijing genotype strains (23.8%, 36/151) showed higher clustering rate than non-Beijing genotype strains (16/120, 13.3%, = 0.029). In conclusion, our data demonstrated that the Beijing genotype was the predominant genotype in Yunnan Province. The distribution of Beijing genotype strains showed geographic diversity. In addition, Beijing genotype was associated with recent transmission rather than drug resistance.
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http://dx.doi.org/10.1155/2017/2505172DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5449728PMC
March 2018

Swelling and hydrolysis kinetics of Kraft pulp fibers in aqueous 1-butyl-3-methylimidazolium hydrogen sulfate solutions.

Carbohydr Polym 2016 Nov 25;153:284-291. Epub 2016 Jul 25.

Chair of Forest Biomaterials, Faculty of Environment and Natural Resources, Albert-Ludwig-University of Freiburg, Werthmannstr. 6, 79085 Freiburg, Germany; Freiburg Materials Research Center (FMF), Albert-Ludwig-University of Freiburg, Stefan-Meier Str. 21, 79104 Freiburg, Germany. Electronic address:

1Butyl-3-methylimidazolium hydrogen sulfate ([Bmim]HSO4) is efficient at extracting cellulose nanocrystals from pulp fibers. To shed some light on the respective contributions of swelling and hydrolysis of pulp fibers by [Bmim]HSO4, the physical, structural and morphological characteristics of hardwood Kraft pulp fibers were monitored under various conditions of temperature, water content and time. Swelling was largely compounded by hydrolysis at the highest temperatures (120°C) as evidenced by mass loss and reduced degree of polymerization (DPn) at this temperature. At 120°C only, water content appeared to play a significant role on the extent of hydrolysis. At this temperature, a heterogeneous kinetic model involving weak links and amorphous regions best described the experimental data. Hydrolysis rates were maximum at 25% water content in the aqueous ionic liquid.
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http://dx.doi.org/10.1016/j.carbpol.2016.07.092DOI Listing
November 2016

The Characteristics Variation of Hepatic Progenitors after TGF-β1-Induced Transition and EGF-Induced Reversion.

Stem Cells Int 2016 3;2016:6304385. Epub 2016 Feb 3.

Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing Key Laboratory of Translational Medicine in Liver Cirrhosis & National Clinical Research Center of Digestive Diseases, Beijing 100050, China; Municipal Laboratory for Liver Protection and Regulation of Regeneration, Capital Medical University, Beijing 100050, China.

Profibrogenesis cytokine, transforming growth factor- (TGF-) β1, induces hepatic progenitors experiencing epithelial to mesenchymal transition (EMT) to matrix synthesis cells, even tumor initiating cells. Our previous data found that epidermal growth factor (EGF) blocks and reverses TGF-β1-induced transition. The aim of this study is to determine the characteristic changes of hepatic progenitors after TGF-β1-induced transition and EGF-induced reversion. Hepatic oval cells, rat hepatic progenitors, were isolated from rats fed a choline-deficient diet supplemented with ethionine. TGF-β1-containing medium was used for inducing EMT, while EGF-containing medium was used for reversing EMT. During TGF-β1-induced transition and EGF-induced reversion, hepatic oval cells sustained their progenitor cell marker expression, including α-fetoprotein, albumin, and cytokeratin-19. The proliferation ability and differentiation potential of these cells were suppressed by TGF-β1, while EGF resumed these capacities to the level similar to the control cells. RNA microarray analysis showed that most of the genes with significant changes after TGF-β1 incubation were recovered by EGF. Signal pathway analysis revealed that TGF-β1 impaired the pathways of cell cycle and cytochrome P450 detoxification, and EGF reverted TGF-β1 effects through activating MAPK and PI3K-Akt pathway. EGF reverses the characteristics impaired by TGF-β1 in hepatic oval cells, serving as a protective cytokine to hepatic progenitors.
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http://dx.doi.org/10.1155/2016/6304385DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4756202PMC
March 2016

Paclobutrazol Residue Determination in Potato and Soil Using Low Temperature Partition Extraction and Ultrahigh Performance Liquid Chromatography Tandem Mass Spectrometry.

J Anal Methods Chem 2015 10;2015:404925. Epub 2015 Sep 10.

Supervision & Testing Center for Farm Product Quality, Ministry of Agriculture, Kunming, China ; Laboratory of Quality & Safety Risk Assessment for Agro-Product, Ministry of Agriculture, Kunming, China ; Institute of Quality Standard and Testing Technology, Yunnan Academy of Agriculture Science, Kunming 650223, China.

A simple, accurate, and highly sensitive analytical method was developed for determining the paclobutrazol residue in potato and soil, the dynamics dissipation in soil. Extraction was carried out by low temperature partitioning and analyzed by ultrahigh performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). For a favor extraction yield, the parameters such as temperature and solvent were optimized. The result showed that sample would be easily frozen and separated using acetonitrile under -20°C for 10 min. The limit of detection (LOD) was 0.5 μg/kg, and the limit of quantification (LOQ) was 2 and 5 μg/kg for potato and soil, respectively. The influence of paclobutrazol residue in potato was evaluated. The possible contamination of paclobutrazol from surface can be rinsed by distilled water or peeled off, but the paclobutrazol in potato harvest comes mainly from absorption and transport, which could not be removed by peeling. The half-life of paclobutrazol in soil was 20.64 days, and the residue was below 0.22 mg/kg on 50th day after spraying. According to the risk assessment with Need Maximum Daily Intake (NEDI) and Acceptable Daily Intake (ADI), a Maximum Residue Limit (MRL) of paclobutrazol in potato was recommended as 1.0 mg/kg.
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http://dx.doi.org/10.1155/2015/404925DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4584097PMC
October 2015

Low serum free thyroxine concentrations associate with increased arterial stiffness in euthyroid subjects: a population-based cross-sectional study.

Endocrine 2015 Nov 19;50(2):465-73. Epub 2015 May 19.

Department of Endocrinology, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China.

Some studies suggest that even in euthyroid subjects, thyroid function may affect arteriosclerotic risk factors. We aimed to determine whether thyroid hormones or thyroid autoantibodies are associated with arterial stiffness in middle-aged and elderly Chinese subjects with euthyroidism. A cross-sectional, population-based study was conducted in Nanjing, China. A total of 812 euthyroid subjects (mean age [56.75 ± 8.34] years; 402 men) without vascular disease and major arteriosclerotic risk factors were included. Clinical factors, oral glucose tolerance test results, homeostasis model assessment for insulin resistance (HOMA-IR) results, and serum levels of lipids, free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), and thyroid autoantibodies were measured. Arterial stiffness was assessed using brachial-ankle pulse wave velocity (baPWV). In Pearson correlation analyses, baPWV correlated inversely with FT4 (r = -0.146, P < 0.001), but not with FT3 (r = 0.008, P = 0.816) or TSH (r = 0.055, P = 0.118). Subsequently, a multiple stepwise regression analysis revealed a significant and independent association of FT4 with baPWV in euthyroid subjects (β = -0.076, P = 0.005). After adjusting for potential cardiovascular risk factors, mean diastolic blood pressure (DBP), HOMA-IR, and baPWV levels decreased across increasing FT4 quartiles (DBP, P < 0.001; HOMA-IR, P < 0.001; baPWV, P = 0.003). No difference in baPWV was observed between the positive and the negative thyroid antibody groups (15.23 ± 3.30 m/s vs. 15.73 ± 3.05 m/s, P > 0.05). FT4 levels were inversely associated with arterial stiffness in euthyroid subjects. A prospective study is warranted to validate whether subjects with low-normal FT4 levels have a high incidence of cardiovascular disease.
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http://dx.doi.org/10.1007/s12020-015-0602-1DOI Listing
November 2015

Cellulose nanocrystals' production in near theoretical yields by 1-butyl-3-methylimidazolium hydrogen sulfate ([Bmim]HSO4)-mediated hydrolysis.

Carbohydr Polym 2015 Mar 13;117:443-451. Epub 2014 Oct 13.

Chair of Forest Biomaterials, Faculty of Environment and Natural Resources, Albert-Ludwig-University of Freiburg, Werthmannstr. 6, 79085 Freiburg, Germany; Freiburg Materials Research Center (FMF), Albert-Ludwig-University of Freiburg, Stefan-Meier Str. 21, 79104 Freiburg, Germany. Electronic address:

We report on near theoretical yield production of cellulose I nanocrystals (CNCs) using a two-step hydrolysis with the mildly acidic ionic liquid (IL) 1-butyl-3-methylimidazolium hydrogen sulfate ([Bmim]HSO4) in aqueous solution from common cellulosic sources. Two successive Taguchi experimental plans were performed to evaluate the impact of selected reaction parameters (T, t, H2O:IL ratio) and their interactions on the CNCs' yield from bleached softwood kraft pulp (SWP), bleached hardwood kraft pulp (HWP) and microcrystalline cellulose (MCC). With these experimental plans, the molar yield for extraction of nanocrystals was optimized to near theoretical levels, reaching 57.7±3.0%, 57.0±2.0%, and 75.6±3.0%, for SWP, HWP and MCC, respectively. The reaction yields corresponded to a relative crystalline region recovery of 84.1±5.3%, 71.7±1.3%, 76.0±2.0% from SWP, HWP and MCC, respectively. The collected nanocrystals exhibited high aspect ratios (36-43), negligible sulfur content (0.02-0.21%) and high solvent dispersibility in comparison to those obtained with the traditional sulfuric acid method. Additionally these near theoretical yields were achieved for mild reaction conditions with the combined severity factor of 2 and 3 for MCC and pulp, respectively. Overall this two-stage IL-mediated preparation of nanocrystals combines the advantages of achieving high product quality, high reaction yields and mild conditions.
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http://dx.doi.org/10.1016/j.carbpol.2014.10.001DOI Listing
March 2015

Visceral adiposity index may be a surrogate marker for the assessment of the effects of obesity on arterial stiffness.

PLoS One 2014 8;9(8):e104365. Epub 2014 Aug 8.

Department of Endocrinology, First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.

Objective: The relationship between obesity and cardiovascular disease (CVD) remains unclear. This study aims to describe the relationship between arterial stiffness and obesity in order to investigate the effects of obesity on CVD.

Methods: We collected data from 5,158 individuals over 40 years of age from a cross-sectional study in Nanjing, China. Anthropometric, demographic, hemodynamic measurements and arterial stiffness measured through brachial-ankle pulse wave velocity (baPWV) were obtained. Subjects were grouped by body mass index (BMI), waist circumference (WC) and visceral adiposity index (VAI), a sex-specific index based on BMI, WC, triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C).

Results: The multivariate regression analysis revealed a negative but weak effect of BMI (β = -0.047, P<0.001) on baPWV, but failed to demonstrate any significant effect of WC on baPWV while VAI was a positive independent indicator of baPWV (β = 0.023, P = 0.022). The unadjusted baPWV significantly increased across groups with higher obesity categories (P<0.01). Although the positive association was lost after adjustments for confounding factors in the BMI or WC categories (P>0.05), it was still obtained between baPWV and VAI quartile (P<0.01). No differences were observed among the metabolically healthy groups or the metabolically abnormal groups in the BMI and WC categories (P>0.05). However, baPWV significantly increased across groups with higher VAI categories even in the same metabolic category (P<0.01).

Conclusions: This study supports the concept of heterogeneity of metabolic status among individuals within the same obesity range. Obese individuals are at an increased risk of arterial stiffness regardless of their metabolic conditions. VAI may be a surrogate marker for the assessment of obesity and the effects of obesity on arterial stiffness.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0104365PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4126713PMC
December 2015

Association of high vitamin d status with low circulating thyroid-stimulating hormone independent of thyroid hormone levels in middle-aged and elderly males.

Int J Endocrinol 2014 16;2014:631819. Epub 2014 Feb 16.

Department of Endocrinology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China.

Background. A recent study has reported that high circulating 25-hydroxyvitamin D [25(OH)D] is associated with low circulating thyroid-stimulating hormone (TSH) levels, but only in younger individuals. The goal of the present study was to explore the relationship between vitamin D status and circulating TSH levels with thyroid autoimmunity and thyroid hormone levels taken into consideration in a population-based health survey of middle-aged and elderly individuals. Methods. A total of 1,424 Chinese adults, aged 41-78 years, were enrolled in this cross-sectional study. Serum levels of 25(OH)D, TSH, thyroid hormones, and thyroid autoantibodies were measured. Results. The prevalence of vitamin D insufficiency was 94.29% in males and 97.22% in females, and the prevalence of vitamin D deficiency was 55.61% in males and 69.64% in females. Vitamin D status was not associated with positive thyroid autoantibodies after controlling for age, gender, body mass index, and smoking status. Higher 25(OH)D levels were associated with lower TSH levels after controlling for age, FT4 and FT3 levels, thyroid volume, the presence of thyroid nodule(s), and smoking status in males. Conclusion. High vitamin D status in middle-aged and elderly males was associated with low circulating TSH levels independent of thyroid hormone levels.
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http://dx.doi.org/10.1155/2014/631819DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3947886PMC
April 2014
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