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1.
J Nanosci Nanotechnol ; 20(3): 1704-1708, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492333

RESUMO

In this study, the optical and electrical properties of a zinc tin oxide (ZTO) thin-film transistor (TFT) were investigated. The TFT was fabricated using ZTO as the active layer, which was deposited by a radio frequency magnetron sputtering system, to form an ultraviolet (UV) photodetector. The device has a threshold voltage of 0.48 V, field-effect mobility of 1.47 cm²/Vs in the saturation region, on/off drain current ratio of 2×106, and subthreshold swing of 0.45 V/decade in a dark environment. Moreover, as a UV photodetector, the device has a long photoresponse time, responsivity of 0.329 A/W, and rejection ratio of 3.19×104 at a gate voltage of -15 V under illumination of wavelength 300 nm.

2.
J Nanosci Nanotechnol ; 20(2): 789-801, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383074

RESUMO

Magnetic Ni0.5Cu0.5Fe2O4/SiO2 nanocomposites were prepared via a solution combustion process, and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), Energy dispersive X-ray Spectroscopy (EDX) and vibrating sample magnetometer (VSM). The magnetic Ni0.5Cu0.5Fe2O4/SiO2 nanocomposites were employed to remove Congo red (CR) from aqueous solution, and the adsorption process was optimized by response surface methodology (RSM). The optimum conditions were the silica content of 12.6 wt%, the calcination temperature of 501 °C and the pH value of 7.13. The adsorption kinetics and the adsorption isotherm of CR onto magnetic Ni0.5Cu0.5Fe2O4/SiO2 nanocomposites at room temperature were investigated, and the intraparticle diffusion kinetics model and Redlich-Peterson isotherm model fitted well the respective process.

3.
Clin Cancer Res ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31484667

RESUMO

PURPOSE: Vα24-invariant natural killer T cells (NKTs) are attractive carriers for chimeric antigen receptors (CARs) due to their inherent antitumor properties and preferential localization to tumor sites. However, limited persistence of CAR-NKTs in tumor-bearing mice is associated with tumor recurrence. Here, we evaluated whether co-expression of the NKT homeostatic cytokine IL-15 with a CAR enhances the in vivo persistence and therapeutic efficacy of CAR-NKTs. EXPERIMENTAL DESIGN: Human primary NKTs were ex vivo expanded and transduced with CAR constructs containing an optimized GD2-specific single-chain variable fragment and either the CD28 or 4-1BB costimulatory endodomain, each with or without IL-15 (GD2.CAR or GD2.CAR.15). Constructs that mediated robust CAR-NKT cell expansion were selected for further functional evaluation in vitro and in xenogeneic mouse models of neuroblastoma (NB). RESULTS: Co-expression of IL-15 with either costimulatory domain increased CAR-NKT absolute numbers. However, constructs containing 4-1BB induced excessive activation-induced cell death and reduced numeric expansion of NKTs compared with respective CD28-based constructs. Further evaluation of CD28-based GD2.CAR and GD2.CAR.15 showed that co-expression of IL-15 led to reduced expression levels of exhaustion markers in NKTs and increased multi-round in vitro tumor cell killing. Following transfer into mice bearing NB xenografts, GD2.CAR.15 NKTs demonstrated enhanced in vivo persistence, increased localization to tumor sites, and improved tumor control compared to GD2.CAR NKTs. Importantly, GD2.CAR.15 NKTs did not produce significant toxicity as determined by histopathological analysis. CONCLUSIONS: Our results informed selection of the CD28-based GD2.CAR.15 construct for clinical testing and led to initiation of a first-in-human CAR-NKT clinical trial (NCT03294954).

5.
J Formos Med Assoc ; 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31477484

RESUMO

Continuous strengthening of the safety of blood products to reduce the risk of transfusion-transmitted HCV in recipients is an important issue of Taiwanese government concern. Since 2013, highly sensitivity serology and NAT assays were simultaneously used for blood donation screening to shorten the window period of HIV, HBV and HCV infections. 15 cases of suspected transfusion-transmitted HCV infection were analyzed in 2015-2018. No HCV nucleic acid was detected among a total 91 bags of donated blood. Eleven cases among the 15 suspected recipients were positive for HCV nucleic acid, and 9 recipients had genotype results. Of these 9 recipients, five for genotype 1b (5/9, 55.6%), three for genotype 2a (3/9, 33.3%) and one for genotype 2b (1/9, 11.1%). We will continuously monitor the blood safety of recipients. There have been no confirmed cases of acute hepatitis C (AHC) infection due to transfusions of HCV contaminated blood product in 2015-2018 in Taiwan.

6.
Phys Chem Chem Phys ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31478043

RESUMO

The polyamide (PA) layer on the surface of thin-film-composite reverse osmosis membranes is the core aspect of membrane-based desalination technology. In recent years, molecular dynamics simulations have been increasingly used to disclose the physicochemical properties of the PA layer. However, the currently reported all-atom PA layer models do not exhibit gradient variation of the structural properties of the layer, and they can only represent the innermost region of the PA layer. With the help of our recently developed universal toolkit "MembrFactory", this paper reports a modeling method that can be used to construct a gradient crosslinking model and surface grafting model for the PA layer. A fully atomistic model of the PA layer was constructed, in which the degree of crosslinking (DC) was changed gradiently along the thickness direction. The structure of the PA layer model and the transport dynamics of the water molecules within it were systematically investigated using equilibrium molecular dynamics simulations. We found that the DC is the lowest and the water molecules have the strongest self-diffusion ability in the interfacial region of the PA layer model. Meanwhile, the pore size is distributed widely in the region. Subsequently, we modified the surface of the PA layer model with PEG coatings, and their coverage ratio was around 75%. The radial distribution function analysis showed that water molecules prefer to coordinate with the oxygen atoms in PEG. Furthermore, two contaminant molecules, 1-ethyl-2-methyl benzene and n-decane, were selected to investigate the antifouling properties of the PEG-modified PA layer. By analysing the trajectories of the pollutants and calculating the potential of the mean force, we found that the antifouling performance of a PEG-modified PA layer is not only related to the hydrophobicity and the size of the pollutant, but is also related to the coverage ratio of the PEG layer.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31478174

RESUMO

Phosphorus (P) characteristics in eutrophic lakes change during algal growth. Furthermore, algae have a significant relationship with the microbial communities of lake sediments. This study addressed the influence of algal growth and soluble reactive phosphorus (SRP) concentrations on P characteristics within the sediment-water-algal (SWA) system. Results indicated that the SWA system simulating a high algal bloom level (SWA-HAB) had a correspondingly high SRP concentration (258.9 µg L-1), and that algal growth promoted a high SRP concentration in the overlying water. The high SRP concentration in overlying water could support algal growth, resulting in a high chlorophyll a (Chl-a) concentration (285.23 mg L-1). During algal growth, the P release flux was high in sediments from the high-SRP SWA system, with the highest P release flux measured at 0.982 mg m-2 day-1. Furthermore, microbial community abundance had a significant relationship with Chl-a concentrations in overlying water (p < 0.05) and increases with algae growth.

8.
Chem Commun (Camb) ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31478534

RESUMO

An efficient organocatalytic cyclization strategy was developed to synthesize pharmacologically interesting bicyclic imidazoline derivatives. Morita-Baylis-Hillman carbonates were applied as C3 electrophiles to react with N,C-dinucleophiles for the first time, yielding the desired products in good to excellent yields with outstanding diastereoselectivities. The optically pure bicyclic imidazolines were expeditiously prepared by utilizing the readily available chiral ketene aminals as building blocks. The products were found to inhibit MDM2-p53 binding and cell proliferation. The most potent compound 5c induced the accumulation of MDM2, p53 and p21 proteins in HCT116 cells and blocked interaction between MDM2 and p53.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31479240

RESUMO

Separators are key safety components for electrochemical energy storage systems. However, the intrinsic poor wettability with electrolyte and low thermal stability of commercial polyolefin separators cannot meet the requirements from the ever-expanding market for high power, high energy and high safety power systems, such as lithium metal, lithium-sulfur and lithium-ion batteries. In this study, scalable bendable networks built with ultra-long silica nanowires (SNs) are developed as stable separators for both high-safety and high-power lithium metal batteries. The three-dimensional porous nature (porosity of 73%) and the polar surface of the obtained SNs separators endues a much better electrolyte wettability, larger electrolyte uptake ratio (325 %), higher electrolyte retention ratio (63 %), and ~ 7 times higher ionic conductivity than that of commercial polypropylene (PP) separators. Moreover, the pore-rich structure of SNs separator can aid to evenly distribute lithium and, in turn, suppress the uncontrollable growth of lithium dendrites to a certain degree. Furthermore, the pure inorganic structure endows the SNs separators with excellent chemical and electrochemical stabilities even at elevated temperatures, as well as excellent thermal stability up to 700 °C. This work underpins the utilization of SNs separators as a rational choice for developing high-performance batteries with metallic lithium anode.

10.
Plant Sci ; 287: 110166, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31481226

RESUMO

In angiosperms, cyclic electron flow (CEF) around photosystem I (PSI) is more important for photoprotection under fluctuating light than under constant light. However, the underlying mechanism is not well known. In the present study, we measured the CEF activity, P700 redox state and electrochromic shift signal upon a sudden transition from low to high light in wild-type plants of Arabidopsis thaliana and Bletilla striata (Orchidaceae). Within the first 20 s after transition from low to high light, P700 was highly reduced in both species, which was accompanied with a sufficient proton gradient (ΔpH) across the thylakoid membranes. Meanwhile, the level of CEF activation was elevated. After transition from low to high light for 60 s, the plants generated an optimal ΔpH. Under such condition, PSI was highly oxidized and the level of CEF activation decreased to the steady state. Furthermore, the CEF activation was positively correlated to the P700 reduction ratio. These results indicated that upon a sudden transition from low to high light, the insufficient ΔpH led to the over-reduction of PSI electron carriers, which in turn stimulated the CEF around PSI. This transient stimulation of CEF not only favored the rapid ΔpH formation but also accepted electrons from PSI, thus protecting PSI at donor and acceptor sides. These findings provide new insights into the important role of CEF in regulation of photosynthesis under fluctuating light.

11.
Nanoscale ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31482914

RESUMO

Electrochemiluminescence (ECL) nanomaterials are usually deposited compactly on the surface of electrodes, which may cause poor mass transfer of reactants, thereby resulting in low ECL efficiency. In this work, we developed a novel kind of luminescent material denoted as C-Au-luminol nanospheres (C-Au-Lum NSs) by high dispersion of luminophores on porous carbon nanospheres (PCNSs). C-Au-Lum NSs were facilely prepared by the in situ reduction of chloroauric acid with the luminescent reagent luminol (Lum) on the nano-pores of PCNSs. Plenty of luminescent Au-Lum NPs were dispersedly concentrated inside the numerous pores and hollow interiors of PCNSs, effectively increasing the mass transfer of reagents and accelerating the electron transport inside the porous nanospheres. This greatly improved the availability of luminophores and endowed C-Au-Lum NSs with excellent ECL emission. After further integrating with enzymatic circulation and strand displacement, an ultrasensitive ECL biosensor was achieved for the ultrasensitive detection of an important tumor biomarker, mucin1. The logarithmically linear range from 0.1 pg mL-1 to 1 ng mL-1 with the detection limit of 47.6 fg mL-1 (S/N = 3) was achieved, demonstrating the superior performance of C-Au-Lum NSs. This work would provide new ideas for the construction of high-performance ECL sensing platforms for diverse applications.

12.
Biochim Biophys Acta Bioenerg ; 1860(11): 148073, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31473302

RESUMO

Photosystem I (PSI) is a potential target of photoinhibition under fluctuating light. However, photosynthetic regulation under fluctuating light in field-grown plants is little known. Furthermore, it is unclear how young leaves protect PSI against fluctuating light under natural field conditions. In the present study, we examined chlorophyll fluorescence, P700 redox state and the electrochromic shift signal in the young and mature leaves of field-grown Cerasus cerasoides (Rosaceae). Within the first seconds after any increase in light intensity, young leaves showed higher proton gradient (ΔpH) across the thylakoid membranes than the mature leaves, preventing over-reduction of PSI in the young leaves. As a result, PSI was more tolerant to fluctuating light in the young leaves than in the mature leaves. Interestingly, after transition from low to high light, the activity of cyclic electron flow (CEF) in young leaves increased first to a high level and then decreased to a stable value, while this rapid stimulation of CEF was not observed in the mature leaves. Furthermore, the over-reduction of PSI significantly stimulated CEF in the young leaves but not in the mature leaves. Taken together, within the first seconds after any increase in illumination, the stimulation of CEF favors the rapid lumen acidification and optimizes the PSI redox state in the young leaves, protecting PSI against photoinhibition under fluctuating light in field-grown plants.

13.
J Biol Chem ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492753

RESUMO

GATA3 is a basic and essential transcription factor that regulates many pathophysiological processes and is required for the development of mammary luminal epithelial cells. Loss-of-function GATA3 alterations in breast cancer are associated with poor prognosis. Here, we sought to understand the tumor suppressive functions GATA3 normally performs. We discovered a role for GATA3 in suppressing epithelial-to-mesenchymal transition (EMT) in breast cancer by activating miR-455-3p expression. Enforced expression of miR-455-3p alone partially prevented EMT induced by transforming growth factor ß (TGF-ß) both in cells and tumor xenografts by directly inhibiting key components of TGF-ß signaling. Pathway and biochemical analyses showed that one miRNA-455 target, the TGF-ß-induced protein-ZEB1, recruits the Mi-2/nucleosome remodeling and deacetylase (NuRD) complex to the promotor region of miR-455 to strictly repress the GATA3-induced transcription of this microRNA. Considering that ZEB1 enhances TGF-ß signaling, we delineated a double-feedback interaction between ZEB1 and miR-455-3p, in addition to the repressive effect of miR-455-3p on TGF-ß signaling. Our study revealed that a feedback loop between these two axes, specifically GATA3-induced miR-455-3p expression, could repress ZEB1 and its recruitment of NuRD (MTA1) to suppress miR-455, which ultimately regulates TGF-ß signaling. In conclusion, we identified that miR-455-3p plays a pivotal role in inhibiting EMT and TGF-ß signaling pathway and maintaining cell differentiation. This form the basis of that miR-455-3p might be a promising therapeutic intervention for breast cancer.

14.
Chem Asian J ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31498970

RESUMO

Herein, the photophysical, morphological, optical gain characteristics of a set of trigonal monodisperse starburst conjugated macromolecules ( Tr1-Tr4 ) have been systematically investigated in order to elucidate the influence of the molecular structures on their optoelectronic performance.  With increasing the oligofluorene arm length, absorption spectra were red-shifted progressively, while an increase in photoluminescence quantum yields (PLQYs) and optical gain coefficients and a corresponding reduction in amplified spontaneous emission (ASE) thresholds and loss coefficients were observed for Tr1-Tr3 except for Tr4 . The results indicate that the effective conjugation length become saturated for Tr3 in this system. Impressively, the resulting molecules manifested very low ASE thresholds (4.4-11.6 mJ/cm 2 ) with high photostability, as well as high thermal stability. One dimensional distributed feedback (DFB) lasers exhibited a minimum lasing threshold of 10.38 nJ pulse -1 (0.86 kW/cm 2 , 4.325 µJ/cm 2 ) for Tr3 . It should be emphasized that the ASE threshold of Tr1-Tr4 was nearly unchanged from room temperature to 200°C. The results suggest that this kind of truxene-cored conjugated starbursts with high photostability and low lasing thresholds are rather promising gain media for organic semiconductor lasers.

15.
Microbiologyopen ; : e922, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31482696

RESUMO

The genus Laceyella consists of a thermophilic filamentous bacteria. The pure isolate of Laceyella sacchari FBKL4.010 was isolated from Moutai-flavor Daqu, Guizhou Province, China. In this study, the whole genome was sequenced and analyzed. The complete genome consists of one 3,374,379-bp circular chromosome with 3,145 coding sequences (CDSs), seven clustered regularly interspaced short palindromic repeat (CRISPR) regions of 12 CRISPRs. Moreover, we identified that the genome contains genes encoding key enzymes such as proteases, peptidases, and acetolactate synthase (ALS) of the tetramethylpyrazine metabolic pathway. Metabolic pathways relevant to tetramethylpyrazine synthesis were also reconstructed based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) PATHWAY database. Annotation and syntenic analyses using antiSMASH 4.0 also revealed the presence of two gene clusters in this strain that differ from known tetramethylpyrazine synthesis clusters, with one encoding amino acid dehydrogenase (ADH) and the other encoding transaminase in tetramethylpyrazine metabolism. The results of this study provide flavor and genomic references for further research on the flavor-producing functions of strain FBKL4.010 in the Moutai liquor-making process.

16.
Adv Mater ; : e1902791, 2019 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-31496027

RESUMO

Protein/antibody therapeutics have exhibited the advantages of high specificity and activity even at an extremely low concentration compared to small molecule drugs. However, they are accompanied by unfavorable physicochemical properties such as fragile tertiary structure, large molecular size, and poor penetration of the membrane, and thus the clinical use of protein drugs is hindered by inefficient delivery of proteins into the host cells. To overcome the challenges associated with protein therapeutics and enhance their biopharmaceutical applications, various protein-loaded nanocarriers with desired functions, such as lipid nanocapsules, polymeric nanoparticles, inorganic nanoparticles, and peptides, are developed. In this review, the different strategies for intracellular delivery of proteins are comprehensively summarized. Their designed routes, mechanisms of action, and potential therapeutics in live cells or in vivo are discussed in detail. Furthermore, the perspective on the new generation of delivery systems toward the emerging area of protein-based therapeutics is presented as well.

17.
Inorg Chem ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31497944

RESUMO

Presented herein is a group of highly stable Zr-based metal-organic frameworks with bowl-shaped dihydroanthracene-based tetratopic linkers as building blocks. Structural analysis reveals that these frameworks are all two-dimensional but comprise three distinct connectivities of Zr6 nodes. By using the steric hindrance of the nonplanar linker, the connectivity of Zr6 node can be tuned from 8-c to unusual 4-c. Further, through either one-pot synthesis or postsynthetic linker installation strategies, the connectivity of Zr6 node can be tuned from 8-c to 10-c by the insertion of a secondary linear dicarboxylate linker, from which not only the temperature-dependent flexibility of the structure can be effectively controlled with enhanced rigidity and thermal stability but also a scaffold for postsynthetic metalation of Pd(II) catalyst for Heck coupling reaction is offered.

18.
Org Lett ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31497967

RESUMO

The catalytic asymmetric synthesis of α,α-difluoromethylated tertiary alcohols is described, using an asymmetric dihydroxylation reaction. This protocol using either the AD-mix-α or AD-mix-ß allowed an easy access to these valuable fluorinated chiral building blocks, which have been obtained with excellent yields and er. In addition, the reaction was extended to the α-fluoromethylated analogues.

19.
Am J Chin Med ; : 1-24, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488036

RESUMO

Oplopanax elatus (Nakai) Nakai is an oriental herb, the polyyne-enriched fraction of which (PEFO) showed anticolorectal cancer (anti-CRC) effects. Other concomitant components, which are inevitably bio-transformed by gut microbiota after oral administration, might be interfere with the pharmacodynamics of polyynes. However, the influence of human gut microbiota on molecules from O. elatus possessing anticancer activity are yet unknown. In this study, the compounds in PEFO and PEFO incubated with human gut microbiota were analyzed and tentatively identified by HPLC-DAD-QTOF-MS. Two main polyynes ((3S,8S)-falcarindiol and oplopandiol) were not significantly decomposed, but some new unknown molecules were discovered during incubation. However, the antiproliferative effects of PEFO incubated with human gut microbiota for 72 h (PEFO I) were much lower than that of PEFO on HCT-116, SW-480, and HT-29 cells. Furthermore, PEFO possessed better anti-CRC activity in vivo, and significantly induced apoptosis of the CRC cells, which was associated with activation of caspase-3 according to the Western-blot results (P<0.05). These results suggest anticolorectal cancer activity of polyynes might be antagonized by some bio-converted metabolites after incubation with human gut microbiota. Therefore, it might be better for CRC prevention if the polyynes could be orally administrated as purified compounds.

20.
Small ; : e1804404, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31489785

RESUMO

2D materials, namely thin layers of layered materials, are attracting much attention because of their unique electronic, optical, thermal, and catalytic properties for wide applications. To advance both the fundamental studies and further practical applications, the scalable and controlled synthesis of large-sized 2D materials is desired, while there still lacks ideal approaches. Alternatively, the chemical vapor transport reaction is an old but powerful technique, and is recently adopted for synthesizing 2D materials, producing bulk crystals of layered materials or corresponding 2D films. Herein, recent advancements in synthesizing both bulk layered and 2D materials by chemical vapor transport reactions are summarized. Beginning with a brief introduction of the fundamentals of chemical vapor transport reactions, chemical vapor transport-based syntheses of bulk layered and 2D materials, mainly exampled by transition metal dichalcogenides and black phosphorus, are reviewed. Particular attention is paid to important factors that can influence the reactions and the growth mechanisms of black phosphorus. Finally, perspectives about the chemical vapor transport-based synthesis of 2D materials are discussed, intending to redraw attentions on chemical vapor transport reactions.

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