Publications by authors named "Yuxiao Wang"

90 Publications

Development of microcapsules using chitosan and alginate via W/O emulsion for the protection of hydrophilic compounds by comparing with hydrogel beads.

Int J Biol Macromol 2021 Feb 17;177:92-99. Epub 2021 Feb 17.

Department of Food Science, Cornell University, NY 14853, United States.

It is a critical challenge to protect hydrophilic compounds in food or pharmaceutical applications due to their strong tendency to leak out of the capsules into the external aqueous phase. In this work, we developed an encapsulation system that can protect hydrophilic ingredients using polyelectrolyte complexes prepared with chitosan and alginate via water-in-oil (W/O) emulsion. Unlike the traditional preparation of hydrogel beads, in which one material was added dropwise to another that had an opposite charge, we prepared microcapsules by electrostatic interaction between the positively charged -NH groups of chitosan and the negatively charged -COO groups of alginate by W/O emulsion via ultrasonication, which prevented the formation of large complexes. The preparation conditions were optimized at an ultrasonic power of 375 W and alginate/chitosan ratio of 7:5, in which the alginate/chitosan microcapsules presented a good polydispersity index of 0.26 and zeta potential of -44.6 mV. The SEM and TEM images showed the microcapsule contained multiple, irregular, conglutinated spheres with a core and shell structure. High encapsulation efficiency and retention efficiency showed its potential to protect hydrophilic components from harsh environments. This method provides a simple route that can efficiently encapsulate a wide range of food or pharmaceutical hydrophilic ingredients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijbiomac.2021.02.089DOI Listing
February 2021

Multi-Layered, Corona Charged Melt Blown Nonwovens as High Performance PM Air Filters.

Polymers (Basel) 2021 Feb 4;13(4). Epub 2021 Feb 4.

Engineering Research Center of Technical Textiles, Ministry of Education, College of Textiles, Donghua University, Shanghai 201620, China.

Particulate matter (PM) and airborne viruses bring adverse influence on human health. As the most feasible way to prevent inhalation of these pollutants, face masks with excellent filtration efficiency and low press drop are in urgent demand. In this study, we report a novel methodology for producing high performance air filter by combining melt blown technique with corona charging treatment. Changing the crystal structure of polypropylene by adding magnesium stearate can avoid charge escape and ensure the stability of filtration performances. Particularly, the influence of fiber diameter, pore size, porosity, and charge storage on the filtration performances of the filter are thoroughly investigated. The filtration performances of the materials, including the loading test performance are also studied. The melt blown materials formed by four layers presented a significant filtration efficiency of 97.96%, a low pressure drop of 84.28 Pa, and a high quality factor (QF) of 0.046 Pa for paraffin oil aerosol particles. Meanwhile, a robust filtration efficiency of 99.03%, a low pressure drop of 82.32 Pa, and an excellent QF of 0.056 Pa for NaCl aerosol particles could be easily achieved. The multi-layered melt blown filtration material developed here would be potentially applied in the field of protective masks.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/polym13040485DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7913826PMC
February 2021

Enhanced Two-Photon Absorption of Cross-Conjugated Chalcone Derivatives: Modulation of the Effective π-Conjugated Structure.

J Phys Chem A 2020 Dec 15;124(51):10808-10816. Epub 2020 Dec 15.

Department of Physics, Harbin Institute of Technology, Harbin 150001, China.

Three cross-conjugated chalcone derivatives , , and were designed and synthesized to develop excellent organic nonlinear optical (NLO) materials. In a Z-scan experiment, all compounds show good NLO absorption characteristics in the visible to near-infrared region. The photophysical mechanism is confirmed to be two-photon absorption (TPA)-induced excited-state absorption (ESA). Intramolecular charge transfer (ICT) observed in transient absorption spectra (TAS) significantly affects molecular NLO properties. We define the π-conjugated system that dominates the electron transition process in the cross-conjugated structure as the effective π-conjugated structure. Electron transition analysis shows a sufficiently strong ICT can effectively expand the effective π-conjugated structure in these cross-conjugated structures. The TPA cross sections of these compounds at 650 and 750 nm are only in the range of 17-97 GM. However, we achieve a significant enhancement of the TPA cross section at 580 nm (1737-2027 GM) by extending the effective π-conjugated structure. Excited by 580 nm femtosecond laser pulses, all compounds exhibit excellent OL performance and the minimum OL threshold is 4.71 × 10 J/cm. The results show that these cross-conjugated chalcone derivatives have promising applications in OL, and their NLO performance can be effectively improved by modulating the effective π-conjugated structure.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jpca.0c08656DOI Listing
December 2020

In Regard to Kang et al.

Int J Radiat Oncol Biol Phys 2021 Jan;109(1):298-299

Barts and the London School of Medicine and Dentistry, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijrobp.2020.08.053DOI Listing
January 2021

Tuning Nonlinear Optical Behavior by Incorporation of the Chalcogenophene into Twistacenes.

J Phys Chem B 2020 11 12;124(47):10766-10775. Epub 2020 Nov 12.

Department of Physics, Harbin Institute of Technology, Harbin 150001, P. R. China.

Four chalcogenophene-fused acenes containing O, S, Se, or Te, respectively, were presented, and the chalcogenophene effect on linear and nonlinear optics was systematically investigated. Their excited-state absorption performance and two-photon absorption (TPA) capacity could be modulated by the incorporating chalcogen atoms. The experimental results showed that the heavy chalcogen facilitated the intersystem crossing resulting in the presence of the triplet state absorption for and , and the TPA capacity gradually increased with the atomic size of the chalcogens. The theoretical calculation inferred that their nonlinear optical performance was closely related to the contributions of the chalcogenophene component to heterotwistacenes in the final excited state. In addition, was able to work under various laser pulses from femtoseconds to nanoseconds.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jpcb.0c07421DOI Listing
November 2020

Enhancing the Pre-Clerkship Residency Exploration Program (PREP): Medical Students' Suggestions.

J Cancer Educ 2020 12 25;35(6):1070-1071. Epub 2020 Sep 25.

Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s13187-020-01886-zDOI Listing
December 2020

Overview of Undergraduate Oncology Interest Groups: Medical Students' Insights from a National Collaborative Network.

J Cancer Educ 2020 Sep 24. Epub 2020 Sep 24.

Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s13187-020-01887-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7515553PMC
September 2020

The performance of licensed rotavirus vaccines and the development of a new generation of rotavirus vaccines: a review.

Hum Vaccin Immunother 2020 Sep 23:1-17. Epub 2020 Sep 23.

Vaccine Clinical Evaluation Department, Jiangsu Provincial Center for Disease Control and Prevention , Nanjing, China.

Rotavirus, which causes acute gastroenteritis and severe diarrhea, has posed a great threat to children worldwide over the last 30 y. Since no specific drugs and therapies against rotavirus are available, vaccination is considered the most effective method of decreasing the morbidity and mortality related to rotavirus-associated gastroenteritis. To date, six rotavirus vaccines have been developed and licensed by local governments. Notably, Rotarix™ and RotaTeq™ have been recommended as universal agents against rotavirus infection by the World Health Organization; however, lower efficacies were found in less-developed and developing regions with medium and high child mortality than well-developed ones with low child mortality. For now, two promising novel vaccines, Rotavac™ and RotaSiil™ were pre-qualified by the World Health Organization in 2018. Other rotavirus vaccines in the pipeline including neonatal strain (RV3-BB) and several non-replicating rotavirus vaccines with a parenteral delivery strategy are currently undergoing investigation, with the potential to improve the performance of, and eliminate the safety concerns associated with, previous live oral rotavirus vaccines. This paper reviews the important developments in rotavirus vaccines in the last 20 y and discusses problems and challenges that require investigation in the future.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/21645515.2020.1801071DOI Listing
September 2020

Elucidating the Coupling Mechanisms of Rapid Intramolecular Vibrational Energy Redistribution in Nitromethane: Ab Initio Molecular Dynamics Simulation.

J Phys Chem A 2020 Oct 17;124(40):8184-8191. Epub 2020 Sep 17.

School of Physics, Harbin Institute of Technology, Harbin 150001, China.

Ab initio molecular dynamics simulations are presented to investigate the intramolecular vibrational energy redistribution (IVR) of an isolated nitromethane molecule. A number of IVR processes are simulated by monitoring the kinetic energy of vibrational modes under selective low-lying vibrational excitations from their ground states (Δν = 1 or 2). Evolution of the normal-mode kinetic energy gives the ultrafast energy transfer processes from parent modes to daughter modes intuitively. From the ultrafast vibrational transfer made by Fourier transformation of the time-dependent normal-mode kinetic energy, we can capture that the symmetry of the normal modes plays an important role in the anharmonic coupling between the vibrational modes. The results show three symmetry-dependent coupling mechanisms: direct symmetric coupling, overtone-assisted coupling, and rotation-assisted coupling. Furthermore, the calculated efficiencies of IVR also coincide with these mechanisms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jpca.0c04995DOI Listing
October 2020

A randomized, double-blind, placebo-controlled study of B-cell lymphoma 2 homology 3 mimetic gossypol combined with docetaxel and cisplatin for advanced non-small cell lung cancer with high expression of apurinic/apyrimidinic endonuclease 1.

Invest New Drugs 2020 12 11;38(6):1862-1871. Epub 2020 Jun 11.

Cancer Center, Daping Hospital & Army Medical Center of PLA, Army Medical University, 400042, Chongqing, China.

Background Overexpression of apurinic/apyrimidinic endonuclease 1 (APE1) is an important cause of poor chemotherapeutic efficacy in advanced non-small cell lung cancer (NSCLC) patients. Gossypol, a new inhibitor of APE1, in combination with docetaxel and cisplatin is believed to improve the efficacy of chemotherapy for advanced NSCLC with high APE1 expression. Methods Sixty-two patients were randomly assigned to two groups. Thirty-one patients in the experimental group received 75 mg/m docetaxel and 75 mg/m cisplatin on day 1 with gossypol administered at 20 mg once daily on days 1 to 14 every 21 days. The control group received placebo with the same docetaxel and cisplatin regimen. The primary endpoint was progression-free survival (PFS); secondary endpoints included overall survival (OS), response rate, and toxicity. Results There were no significant differences in PFS and OS between the experimental group and the control group. The median PFS (mPFS) in the experimental and control groups was 7.43 and 4.9 months, respectively (HR = 0.54; p = 0.06), and the median OS (mOS) was 18.37 and 14.7 months, respectively (HR = 0.68; p = 0.27). No significant differences in response rate and serious adverse events were found between the groups. Conclusion The experimental group had a better mPFS and mOS than did the control group, though no significant difference was observed. Because the regimen of gossypol combined with docetaxel and cisplatin was well tolerated, future studies with larger sample sizes should be performed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10637-020-00927-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7575477PMC
December 2020

The formation process of green substances in Chrysanthemum morifolium tea.

Food Chem 2020 Oct 16;326:127028. Epub 2020 May 16.

College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; National Engineering Research Center for Fruit and Vegetable Processing, Beijing 100083, China. Electronic address:

One interesting phenomenon of Chrysanthemum morifolium tea is its formation of a green or dark green color after hours of brewing, and it is important to study the compounds that form this color and whether they might be involved in health benefits. Non-targeted metabolomics could clearly distinguish between green and non-green species by sparse partial least squares discriminant analysis (sPLS-DA) and heat-mapping. We found that the pH was the primary factor in the formation of the green color. Two green precursors (GP1 and GP2) were separated and purified with preparative HPLC. FT-IR analysis and the saccharide content analysis showed that GP1 had the typical characteristics of saccharides. GP2 was identified as chlorogenic acid by ESI-Q-TOF/MS and NMR. We raised the formation process of green substances was caused by the hydrolysates of chlorogenic acid reacting with glycosides or groups attached to the saccharides, which suggests a new mechanism for color-forming reactions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.foodchem.2020.127028DOI Listing
October 2020

Activated Hepatic Stellate Cells (HSCs) Exert Immunosuppressive Effects in Hepatocellular Carcinoma by Producing Complement C3.

Onco Targets Ther 2020 18;13:1497-1505. Epub 2020 Feb 18.

Department of Hematology, The First Affiliated Hospital of Xiamen University and Institute of Hematology, Medical College of Xiamen University, Xiamen 361003, People's Republic of China.

Objective: Hepatic stellate cells (HSCs) are the important players in liver cirrhosis and liver cancer. They also act as critical mediators of immunosuppression in hepatocellular carcinoma (HCC). In this study, we hypothesized that HSCs promote HCC progression via C3.

Methods: C3 in HSCs was knocked down using a shRNA retroviral plasmid. The conditioned medium from HSCs or shC3 HSCs (knockdown of C3 by shRNA in HSCs) was collected to detect their effects on bone marrow (BM) and T cells (including expansion and apoptosis) in vitro, and in an HCC in situ model in mice.

Results: We found that HSCs promoted T-cell apoptosis and decreased their proliferation, inhibited dendritic cell (DC) maturation, and induced myeloid-derived suppressor cell (MDSC) expansion through the C3 pathway in vitro. In addition, the knockdown of C3 suppressed HSC-promoted HCC development in the orthotopic transplantation tumor model of HCC in mice.

Conclusion: These findings provide more insights into the immunomodulatory roles of HSCs in HCC progression and indicate that modulation of the C3 pathway might be a novel therapeutic approach for liver cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/OTT.S234920DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7035898PMC
February 2020

Polytetrafluoroethylene/Polyphenylene Sulfide Needle-Punched Triboelectric Air Filter for Efficient Particulate Matter Removal.

ACS Appl Mater Interfaces 2019 Dec 16;11(51):48437-48449. Epub 2019 Dec 16.

Key Laboratory of Textile Science & Technology, Ministry of Education, College of Textiles , Donghua University , Shanghai 201620 , China.

The demand for air filtration materials in recent years has been substantially increasing on a worldwide scale because people are paying extensive attention to particulate matter (PM) pollution. In this work, we report a type of needle-punched triboelectric air filter (N-TAF) consisting of polytetrafluoroethylene (PTFE) fibers modified by silica nanoparticles and polyphenylene sulfide (PPS) fibers. Compared to conventional electrostatic precipitators, the N-TAF can be charged online by a unique nonwoven processing technology without additional energy consumption and toxic ozone emission. Owing to the triboelectrification effect, a large number of charges were generated during the process of carding and needle-punching, resulting in an increased filtration performance. Benefiting from the addition of silica nanoparticles, the PTFE fibers are endowed with many pores and grooves and substantial surface roughness, which contributes to the enhancement of triboelectrification. As a result, the N-TAF with 2 wt % silica nanoparticles (N-TAF-2) exhibited a high removal efficiency of 89.4% for PM, which is 45% higher than unmodified N-TAF (61.8%), and a low pressure drop of 18.6 Pa. Meanwhile, the decay of the removal efficiency for N-TAF-2 remained at a low level (6.4%) for 60 days. More importantly, N-TAF-2 could realize a high efficiency of 99.7% and a low pressure drop of 55.4 Pa at a high surface density. In addition, the washed N-TAF has an excellent charge regeneration performance via air blowing or manual rubbing, thus recovering the removal efficiency easily and rapidly. Ultimately, the powerful dust holding capacity (227 g m) for N-TAF-2 indicates that the filter has a long service life, which makes it a promising air purification material. The filter reported in this work has the potential to be practically applied to air purification fields because it has excellent filtration performance and is easy to be produced on a large industrial scale.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsami.9b18341DOI Listing
December 2019

An alternative pathway for repair of deaminated bases in DNA triggered by archaeal NucS endonuclease.

DNA Repair (Amst) 2020 01 24;85:102734. Epub 2019 Oct 24.

State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.

Recent studies show that NucS endonucleases participate in mismatch repair in several archaea and bacteria. However, the function of archaeal NucS endonucleases has not been completely clarified. Here, we describe a NucS endonuclease from the hyperthermophilic and radioresistant archaeon Thermococcus gammatolerans (Tga NucS) that can cleave uracil (U)- and hypoxanthine (I)-containing dsDNA at 80 °C. Biochemical evidence shows that the cleavage sites of the enzyme are at the second phosphodiester on the 5'- site of U or I, and at the third phosphodiester on the 5'-site of the opposite base of U or I, creating a double strand break with a 4-nt 5'-overhang.The ends of the cleaved product of Tga NucS are ligatable, possessing 5'-phosphate and 3'-hydroxyl termini, which can be utilized by DNA repair proteins or enzymes. Tga NucS displays a preference for U/G- and I/T-containing dsDNA over other pairs with U or I, suggesting that the enzyme is responsible for repair of U and I in DNA that arise from deamination. Biochemical characterization of cleaving U- and I-containing DNA by Tga NucS was also investigated. The DNA-binding results show that the enzyme exhibits a higher affinity for normal, U- and I-containing dsDNA than for normal, U- and I-containing ssDNA. Therefore, we present an alternative pathway for repair of deaminated bases in DNA triggered by archaeal NucS endonuclease in hyperthermophilic archaea.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.dnarep.2019.102734DOI Listing
January 2020

Vibrio vulnificus cytolysin induces inflammatory responses in RAW264.7 macrophages through calcium signaling and causes inflammation in vivo.

Microb Pathog 2019 Dec 9;137:103789. Epub 2019 Oct 9.

Central Laboratory, The Sixth Medical Center of Chinese PLA General Hospital, Beijing, 100048, China. Electronic address:

Vibrio vulnificus is a food-borne marine pathogen that causes both life-threatening primary septicemia and necrotizing wound infections which accompany severe inflammation. Cytolysin is a very powerful virulence factor of V. vulnificus and is one of the likely candidates in the pathogenesis of V. vulnificus infections. However, the pathogenetic roles of cytolysin in V. vulnificus-induced inflammation are not well understood. In this study, we used the recombinant protein Vibrio vulnificus cytolysin (VVC) to demonstrate that VVC can induce inflammatory responses in RAW264.7 macrophages. Low dose (<5 μg/ml) VVC had no impact on cell viability and induced pro-inflammatory cytokines production in RAW264.7 macrophages such as IL-6 and TNF-α. Moreover, VVC induced p65, p38, ERK1/2, and AKT phosphorylation in RAW264.7 macrophages. We further demonstrated that BAPTA-AM, a specific intracellular calcium chelator, inhibited VVC-induced inflammatory responses including pro-inflammatory cytokines production and inflammatory signaling activation in RAW264.7 macrophages. In addition, VVC primed rather than actived NLRP3 inflammasome in RAW264.7 macrophages. To determine whether VVC have a direct inflammatory effect on the host, we examined the effects of VVC injected into the skin of mice. VVC stimulated a significant induction of mRNAs for the pro-inflammatory cytokine IL-6 and inflammatory chemokines such as MCP-1 and IP-10. Histology data also showed that VVC caused inflammatory responses in the skin of mice. Collectively, our findings indicated that VVC induced inflammatory responses in RAW264.7 macrophages and in vivo and suggested the possibility of targeting VVC as a strategy for the clinical management of V. vulnificus-induced inflammatory responses.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.micpath.2019.103789DOI Listing
December 2019

Polyethylene/Polypropylene Bicomponent Spunbond Air Filtration Materials Containing Magnesium Stearate for Efficient Fine Particle Capture.

ACS Appl Mater Interfaces 2019 Oct 18;11(43):40592-40601. Epub 2019 Oct 18.

Key Laboratory of Textile Science & Technology, Ministry of Education, College of Textiles , Donghua University , Shanghai 201620 , China.

Particulate matter (PM) poses a threat to people's living environment. Fresh air ventilation systems can filter particulate matter and play an important role in enhancing indoor air quality. A high filtration efficiency material with low pressure drop prolongs the service life of the filters and reduces energy consumption. However, maintaining the long-term storage of charge in electret materials remains a challenge. Herein, we report a novel sheath/core bicomponent spunbond (BCS) electret material with low pressure drop and improved charge stability using polyethylene/polypropylene (PE/PP) as the matrix polymer and magnesium stearate (MgSt) as the charge enhancer. Benefiting from the three-dimensional (3D) fluffy structure created by the spunbond technique and through-air reinforcement, the resulting electret materials exhibit a low pressure drop of 37.92 Pa, excellent dust holding capacity of 10.87 g m, and high filtration efficiency of 98.94%. Moreover, due to the introduction of MgSt, the filtration efficiency only decreased by 4.1% in 90 days. The successful fabrication of PE/PP BCS materials with MgSt not only provided a promising medium for particle capture but also developed a new approach for the design of fresh air filtration materials.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsami.9b13162DOI Listing
October 2019

Characterization of a novel anti-human lymphocyte activation gene 3 (LAG-3) antibody for cancer immunotherapy.

MAbs 2019 Aug/Sep;11(6):1139-1148. Epub 2019 Jun 26.

a Central Laboratory, Navy General Hospital of PLA , Beijing , China.

Lymphocyte activation gene 3 (LAG-3) is expressed on activated T cells, natural killer cells or B cells, and functions to negatively regulate homeostasis of these cells. Anti-LAG-3 antibodies might be useful for antitumor immunotherapy. In this study, we characterized a novel anti-LAG-3 antibody, LBL-007, which was isolated from a human antibody phage display library. LBL-007 was found to specifically bind to human LAG-3 antigen, but not to human CD4 or mouse LAG-3. LBL-007 bound activated T cells and promoted interleukin-2 secretion. LBL-007 internalization efficacy by endocytosis into different cells was better than that of another anti-LAG-3 antibody, relatlimab analog. Moreover, LBL-007 was able to block LAG-3 binding to MHC class II molecules and liver sinusoidal endothelial cell lectin, and block LAG-3-induced downstream signaling. In mice transplanted with colorectal cancer cells, treatment with either anti-PD-1 antibody or LBL-007 (10 mg/kg per mouse twice a week for three weeks) resulted in a significant delay in tumor growth compared with control IgG treatment, and their combination was even more effective. Serum LBL-007 levels were highly stable in monkeys after a single intravenous injection of LBL-007 at 3, 10, or 30 mg/kg. This study demonstrated that the combination of LBL-007 with an anti-PD-1 antibody is a promising antitumor regimen for immunotherapy of solid tumors in future that deserves further study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/19420862.2019.1629239DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6748621PMC
January 2020

A biosurfactant-producing Pseudomonas aeruginosa S5 isolated from coking wastewater and its application for bioremediation of polycyclic aromatic hydrocarbons.

Bioresour Technol 2019 Jun 20;281:421-428. Epub 2019 Feb 20.

School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; River Basin Research Center, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.

Although polycyclic aromatic hydrocarbons (PAHs) are considered as toxic and refractory pollutants, their biodegradation can be facilitated by biosurfactants. However, few studies have been performed to understand the potential isolation and application of biosurfactant-producing microorganism for promoting the in-situ removal of PAHs from wastewaters. In this work, a biosurfactant-producing strain S5 isolated from coking wastewater was identified as Pseudomonas aeruginosa. The biosurfactant produced by strain S5 was determined as glycolipid with a critical micelle concentration (CMC) of 96.5 mg/L, and reduced the surface tension from 72.2 to 29.6 mN/m. Addition indigenous P. aeruginosa S5 to coking wastewater effectively promoted the biodegradation of high weight molecular (HWM) PAHs (reduction from 9141.02 to 5117.16 µg/L in 15 days) in sludge phase. The results showed that the removal of PAHs in the sludge was enhanced by inoculating indigenous biosurfactant-producing microorganism in coking wastewater serving as an in-site remediation technology.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.biortech.2019.02.087DOI Listing
June 2019

The formation and bioactivities of green substances in Chrysanthemum morifolium tea.

Food Chem 2019 Jul 14;286:268-274. Epub 2019 Feb 14.

College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; National Engineering Research Center for Fruit and Vegetable Processing, Beijing 100083, China; Key Laboratory of Fruit and Vegetable Processing, Ministry of Agriculture, Beijing 100083, China. Electronic address:

One interesting phenomenon of Chrysanthemum morifolium tea is its formation of green or dark green color after hours of brewing. We investigated the greening reaction and its bioactivities, including an analysis of the green compounds. Results showed that the green color was due to a decrease in the L* (lightness), b* (yellowness/blueness), chroma values and an increase in hue angle. The green substances were found to be substances with similar polarities and unstable in acidic conditions. There was no significant difference (p < 0.01) in antioxidant activity between non-green and green samples. The green substances did not lead to cytotoxicity in PC12 cells at low concentrations, but at high concentrations, they caused a significant (p < 0.01) decrease in cell viability. The saccharide percentage and FT-IR results showed that the greening reaction was affected by the glycosides or groups attached to the saccharides, which might suggest a new mechanism for color-forming reactions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.foodchem.2019.02.026DOI Listing
July 2019

CRACR2a is a calcium-activated dynein adaptor protein that regulates endocytic traffic.

J Cell Biol 2019 05 27;218(5):1619-1633. Epub 2019 Feb 27.

Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA

Cytoplasmic dynein is a minus end-directed microtubule motor that transports intracellular cargoes. Transport is initiated by coiled-coil adaptors that (a) join dynein and its cofactor dynactin into a motile complex and (b) interact with a cargo-bound receptor, which is frequently a Rab GTPase on an organelle. Here, we report two novel dynein adaptors, CRACR2a and Rab45, that have a coiled-coil adaptor domain, a pair of EF-hands, and a Rab GTPase fused into a single polypeptide. CRACR2a-mediated, but not Rab45-mediated, dynein motility is activated by calcium in vitro. In Jurkat T cells, elevation of intracellular calcium activates CRACR2a-mediated dynein transport. We further found that T cell receptor activation induces the formation of CRACR2a puncta at the plasma membrane, which initially associate with the actin cortex and subsequently detach and travel along microtubules, suggestive of an endocytic process. These results provide the first examples of Rab GTPases that directly act as dynein adaptors and implicate CRACR2a-dynein in calcium-regulated endocytic trafficking.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1083/jcb.201806097DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6504896PMC
May 2019

Effect of Weakly Basic Conditions on the Separation and Purification of Flavonoids and Glycosides from Tea.

Molecules 2019 Jan 15;24(2). Epub 2019 Jan 15.

College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.

Tea brewed from chrysanthemum flowers has been widely used in Chinese medicine. The possibly medicinal compounds in tea can be purified by preparative high performance liquid chromatography (HPLC), but this is usually done with acidic conditions, which leads to the hydrolysis of glycosides. In hopes of avoiding this hydrolysis, we explored the effect of weakly basic conditions on the separation and purification of flavonoids and glycosides from . We also explored the effects of weakly basic conditions on chlorogenic acid (3-CQA) and apigenin-7--glucoside (A7G). Our results show that the concentration of the weakly basic ammonium hydrogen carbonate and time had no significant effect on A7G, < 0.01, but it had a significant effect on 3-CQA, < 0.01. HPLC and ultraviolet (UV) analysis showed that the structure of 3-CQA is destroyed in weakly basic conditions. Caffeic acid, quinic acid, and 3,4-dihydroxymandelic acid, which is a hydrolysate of 3-CQA, were identified by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). The results showed that weakly basic conditions could be used for the purification of flavonoids and glycosides but not for caffeoylquinic acids. Moreover, our work clarified the hydrolysis behaviour of caffeoylquinic acids, which can be helpful for research into their functional aspects.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules24020297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6359300PMC
January 2019

Extraction, Purification, and Hydrolysis Behavior of Apigenin-7-O-Glucoside from Tea.

Molecules 2018 Nov 9;23(11). Epub 2018 Nov 9.

College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.

Apigenin-7-O-glucoside is an active phenolic compound in Asteraceae flowers and possesses remarkable therapeutic applications. However, its high price and low abundance in plants limit its use, meanwhile it would hydrolyze in the purification process. In this study, apigenin-7-O-glucoside extracted with ultrasound and purified with preparative HPLC from 'Huangju' was investigated, as well as its hydrolysis behavior and bioactivities. The optimized extraction conditions were: solid/liquid ratio: 1:20, extraction time: 35 min, temperature: 50 °C, and ultrasound power: 350 W. The content of apigenin-7-O-glucoside was up to 16.04 mg/g. Apigenin-7-O-glucoside was then purified with preparative HPLC from the extract, and confirmed by Q-TOF/MS. Apigenin-7-O-glucoside was partially hydrolyzed in acidic condition, and the hydrolysis rate depended on the pH value and temperature. The antioxidant activity increased as a result of the hydrolysis process. This study provided a green and effective way to obtain apigenin-7-O-glucoside and would be beneficial for further investigations into nutritional and functional aspects apigenin-7-O-glucoside and other glycosides.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules23112933DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6278536PMC
November 2018

Dynamic control of transverse magnetization spot arrays.

Opt Express 2018 Jun;26(13):16824-16835

We propose a feasible strategy for firstly constructing diffraction-limited light-induced magnetization spot arrays capable of dynamically controlling transverse polarization orientation of each spot. To achieve this goal, we subtly design a tailored incident light comprised of two sorts of beams and sufficiently demonstrate tit's production through phase modulation of a radially polarized beam. Via tightly focusing counter-propagating composite illuminating beams in a 4π optical microscopic configuration, two orthogonally polarized focal fields with π/2 phase difference between them are formed, inducing a three-dimensional (3D) super-resolved transverse magnetization spot in the magnetic-optical (MO) film. Exploiting the ideal of the multi-zone plate (MZP) filter, we further achieve versatile magnetization spot arrays with controllable in-plane polarization direction in each spot. Such well-defined magnetization behavior is attributed to not merely the coherent interference of vectorial optical waves, but also non-overlapping superposition of localized focal fields. Our achievable outcomes pave the way for practical applications in spintronics and multi-value MO parallelized storage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.26.016824DOI Listing
June 2018

Arbitrarily spin-orientated and super-resolved focal spot.

Opt Lett 2018 Aug;43(16):3826-3829

In this Letter, we propose a facile approach for achieving a robust focal spot bearing both super-resolution and arbitrary spin orientation. Toward this aim, we meticulously devise a structured incident light consisting of three sorts of beams, which can be produced definitely by the superposition of a radially polarized beam and an azimuthally polarized beam. Based on the vectorial diffraction integral and spin density theory, such newly configurable beams are tightly focused and isotropically interfered in a 4π microscopic configuration to create three polarized field components perpendicular to each other beyond the diffraction limit, thus enabling us to yield a super-resolved focal spot possessing spatial spin axis. By further willfully adjusting the amplitude factors of the reconstituent fields, the photonic spin direction can be freely tunable. The demonstrated results in this Letter may hold great potential for the spin photonics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1364/OL.43.003826DOI Listing
August 2018

Biochemical characterization of a thermostable endonuclease V from the hyperthermophilic euryarchaeon Thermococcus barophilus Ch5.

Int J Biol Macromol 2018 Oct 22;117:17-24. Epub 2018 May 22.

College of Plant Protection, Agricultural University of Hebei, Baoding City, Hebei Province 071001, China.

Endonuclease V (Endo V) is an important enzyme for repairing deoxyinosine in DNA. While bacterial and eukaryotic endo Vs have been well studied, knowledge of archaeal endo Vs is limited. Here, we first presented biochemical characterization of a thermostable endonuclease V from the hyperthermophilic euryarchaeon Thermococcus barophilus Ch5 (Tba endo V). The recombinant enzyme possessed optimal endonuclease activity for cleaving deoxyinosine-containing DNA at 70-90 °C. Furthermore, Tba endo V can withstand 100 °C for 120 min without significant loss of its activity, suggesting the enzyme is thermostable. Tba endo V exhibited varying cleavage efficiencies at various pH levels from 6.0 to 11.0, among which an optimal pH for the enzyme was 8.0-9.0. In addition, a divalent metal ion was required for the enzyme to cleave DNA. Mn and Mg were optimal ions for the enzyme's activity whereas Ca, Zn and Co inhibited the enzyme activity. Moreover, the enzyme activity was suppressed by high NaCl concentration. Tba endo V bound to all DNA substrates; however, the enzyme exhibited a higher affinity for binding to deoxyinosine-containing DNA than normal DNA. Our work provides valuable information for revealing the role of Tba endo V in the base excision repair pathway for deoxyinosine repair in Thermococcus.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijbiomac.2018.05.155DOI Listing
October 2018

Manufacturing Multienzymatic Complex Reactors In Vivo by Self-Assembly To Improve the Biosynthesis of Itaconic Acid in Escherichia coli.

ACS Synth Biol 2018 05 8;7(5):1244-1250. Epub 2018 May 8.

State Key Laboratory of Bioreactor Engineering , East China University of Science and Technology , Shanghai 200237 , China.

The self-assembly of multienzyme into bioreactors is of extensive interest to spatially regulate valuable reactions. Despite the important progresses achieved, methods to precisely manufacture multienzymatic complex reactors (MECRs) are still poorly proposed both in vivo and in vitro, particularly for more than three biocatalytically relevant enzymes. Here, we developed a sequential self-assembly system to form multitude MECRs involving three enzymes in the itaconic acid (IA) pathway with two pairs of protein-peptide interactions. The MECRs were identified as nanoscale particle-like structures when self-assembled in vitro and produced higher IA production than the unassembled and linearly assembled systems when applied in vivo coupling with CRISPR-Cas9 based metabolic engineering. This work provides novel insights into the construction of multifarious multienzyme complex into bioreactors by the self-assembly strategy for multistep cascades to sequentially control metabolic fluxes inside cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acssynbio.8b00086DOI Listing
May 2018

Screening of critical factors influencing the efficient hydrolysis of zeaxanthin dipalmitate in an adapted in vitro- digestion model.

Food Chem 2018 Aug 22;257:36-43. Epub 2018 Feb 22.

Institute of Food Science and Biotechnology, University of Hohenheim, 70599 Stuttgart, Germany; Biological Science Department, King Abdulaziz University, P. O. Box 80257, 21589 Jeddah, Saudi Arabia.

As hydrolysis of carotenoid esters is believed to be highly efficient in vivo, their insufficient hydrolysis in in vitro-digestion models, particularly, regarding zeaxanthin diesters, is a current issue. Therefore, in this study, several factors related to the enzymatic hydrolysis were investigated in an adapted version of the standardized INFOGEST in vitro-digestion model, using zeaxanthin dipalmitate (ZDP) as a substrate. The results showed that pancreatic lipase was able to hydrolyze ZDP, whereas carboxyl ester lipase (CEL) substantially contributed to ZDP cleavage. Replacement of commonly used porcine with bovine bile extracts and the substitution of coffee creamer for soybean oil at identical fat contents both significantly improved hydrolysis efficiency and bioaccessibility of total zeaxanthin to better mimic in vivo conditions. Thus, bile and lipids selection for in vitro digestion of carotenoid esters was crucial. The combined use of coffee creamer, pancreatin, CEL, and bovine bile led to the highest hydrolysis efficiency of 29.5%.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.foodchem.2018.02.116DOI Listing
August 2018

Effectiveness and practical uses of 23-valent pneumococcal polysaccharide vaccine in healthy and special populations.

Hum Vaccin Immunother 2018 04 21;14(4):1003-1012. Epub 2017 Dec 21.

b Jiangsu Provincial Center for Disease Control and Prevention , Nanjing , PR China.

Streptococcus pneumonia (S. pneumoniae) is responsible for significant morbidity and mortality throughout the world. The 23-valent pneumococcal polysaccharide vaccines (PPV23) have been widely used for many years, but challenges are remaining in some respects, especially for its effectiveness among high-risk populations and older adults. This review aims to summarize recent clinical trials and studies of PPV23 vaccination among healthy people ≥ 2 years of age and those with high-risk conditions such as pregnant women, individuals with immunocompromising diseases and other chronic conditions, and provide health officials in China and other developing countries a comprehensive understanding of the current vaccination strategies for PPV23 and for the combined use of PPV23 and pneumococcal conjugate vaccines (PCVs) in adults.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/21645515.2017.1409316DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5893217PMC
April 2018

Theoretical guideline for generation of an ultralong magnetization needle and a super-long conveyed spherical magnetization chain.

Opt Express 2017 Sep;25(19):22268-22279

Considering an azimuthally polarized vortex beam with a Gaussian annulus as an incoming light, light induced magnetization fields for both a single high NA lens and a pair of high NA lenses are investigated theoretically. We deduce analytical formulas for the parameters of a magnetization needle and a magnetization chain when the angular width of the incident beam is far less than its central angular position. Through these analytical formulas, the properties of the magnetization needle and the magnetization chain are very clear and distinct. Compared with parameter optimizing to produce an ultralong magnetization needle with lateral sub-wavelength scale and a super-long spherical magnetization chain with three-dimensional super resolution, the analytical method is direct and has a theoretical guideline. The validity of these formulas is proved, compared to numerical solutions. The present work regarding these super-resolution magnetization patterns is of great value in high density all-optical magnetic recording, atomic trapping as well as confocal and magnetic resonance microscopy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.25.022268DOI Listing
September 2017