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1.
Molecules ; 28(11)2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37298982

ABSTRACT

Conjugated polymer photocatalysts for hydrogen production have the advantages of an adjustable structure, strong response in the visible light region, adjustable energy levels, and easy functionalization. Using an atom- and step-economic direct C-H arylation method, dibromocyanostilbene was polymerized with thiophene, dithiophene, terthiophene, and fused thienothiophene and dithienothiophene, respectively, to produce donor-acceptor (D-A)-type linear conjugated polymers containing different thiophene derivatives with different conjugation lengths. Among them, the D-A polymer photocatalyst constructed from dithienothiophene could significantly broaden the spectral response, with a hydrogen evolution rate up to 12.15 mmol h-1 g-1. The results showed that the increase in the number of fused rings on thiophene building blocks was beneficial to the photocatalytic hydrogen production of cyanostyrylphene-based linear polymers. For the unfused dithiophene and terthiophene, the increase in the number of thiophene rings enabled more rotation freedom between the thiophene rings and reduced the intrinsic charge mobility, resulting in lower hydrogen production performance accordingly. This study provides a suitable process for the design of electron donors for D-A polymer photocatalysts.


Subject(s)
Hydrogen , Tissue Donors , Humans , Polymers , Thiophenes
2.
Opt Lett ; 48(7): 1578-1581, 2023 Apr 01.
Article in English | MEDLINE | ID: mdl-37221714

ABSTRACT

We propose a scheme for the creation of stable optical Ferris wheel (OFW) solitons in a nonlocal Rydberg electromagnetically induced transparency (EIT) medium. Depending on a careful optimization of both the atomic density and the one-photon detuning, we obtain an appropriate nonlocal potential provided by the strong interatomic interaction in Rydberg states that can perfectly compensate for the diffraction of the probe OFW field. Numerical results show that the fidelity remains larger than 0.96, while the propagation distance has exceeded 160 diffraction lengths. Higher-order OFW solitons with arbitrary winding numbers are also discussed. Our study provides a straightforward route to generate spatial optical solitons in the nonlocal response region of cold Rydberg gases.

3.
Molecules ; 28(5)2023 Feb 27.
Article in English | MEDLINE | ID: mdl-36903455

ABSTRACT

In this paper, an atom- and step-economic direct C-H arylation polymerization (DArP) strategy was developed to access cyanostyrylthiophene (CST)-based donor-acceptor (D-A) conjugated polymers (CPs) used for photocatalytic hydrogen production (PHP) from water reduction. The new CST-based CPs CP1-CP5 with varied building blocks were systematically studied by X-ray single-crystal analysis, FTIR, scanning electron microscopy, UV-vis, photoluminescence, transient photocurrent response, cyclic voltammetry measurements, and a PHP test, which showed that the phenyl-cyanostyrylthiophene-based CP3 exhibits a superior hydrogen evolution rate (7.60 mmol h-1 g-1) compared to other conjugated polymers. The structure-property-performance correlation results obtained in this study will provide an important guideline for the rational design of high-performance D-A CPs for PHP applications.

4.
Front Microbiol ; 13: 1011070, 2022.
Article in English | MEDLINE | ID: mdl-36560951

ABSTRACT

Woodchuck (Marmota monax) infected with woodchuck hepatitis virus (WHV) is the most pathogenically compatible naturally occurring model of human hepatitis B virus (HBV) infection, chronic hepatitis B, and HBV-induced hepatocellular carcinoma. This system plays a crucial role in discovery and preclinical evaluation of anti-HBV therapies. Its utilization remains tempered by the relatively narrow range of validated immunologic and molecular tools. We evaluated commercial antibodies against immune cell phenotypic markers and T cell molecules for cross-reactivity with woodchuck antigenic equivalents. The confirmed antibodies against programed cell death protein-1 (PD-1) and its ligand (PD-L1) were examined for ex vivo ability to activate WHV-specific, global and bystander cytotoxic T cells (CTLs) in chronic hepatitis and asymptomatic infection persisting after self-resolved acute hepatitis. Examination of 65 antibodies led to identification or confirmation of 23 recognizing woodchuck T, regulatory T, B and natural killer cells, T cell-associated PD-1, PD-L1, CTLA-4 and TIM-3 molecules, CD25 and CD69 markers of T cell activation, and interferon gamma (IFNγ). Antibodies against woodchuck PD-1 and PD-L1 triggered in vitro highly individualized WHV-specific and global activation of CTLs in both chronic hepatitis and persistent occult infection. WHV-specific CTLs were more robustly augmented by anti-PD-1 than by anti-PD-L1 in chronic hepatitis, while global IFNγ-positive CTL response was significantly suppressed in chronic hepatitis compared to persistent occult infection. Anti-PD-1 and anti-PD-L1 also occasionally activated CTLs to specificities other than those tested suggesting their potency to trigger side effects. This was particularly apparent when T cells from chronic hepatitis were treated with anti-PD-L1. The current findings indicate that inhibition of the PD-1/PD-L1 pathway could reactivate virus-specific and global T cell responses in both chronic hepatitis and asymptomatic persistent infection. They suggest a mechanism of potential reactivation of clinically silent infection during anti-PD-1/PD-L1 treatment and indicate that this therapy may also subdue occult HBV infection.

5.
Chem Commun (Camb) ; 58(91): 12680-12683, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36286612

ABSTRACT

2-Styrylthiophene-based donor-acceptor linear conjugated polymers with tunable cyano substituents are atom-economically obtained via direct C-H arylation for platinum-free photocatalytic hydrogen production, affording a HER of up to 9.79 mmol h-1 g-1.

6.
F1000Res ; 9: 1137, 2020.
Article in English | MEDLINE | ID: mdl-33274050

ABSTRACT

We sequenced the genome of the North American groundhog, Marmota monax, also known as the woodchuck. Our sequencing strategy included a combination of short, high-quality Illumina reads plus long reads generated by both Pacific Biosciences and Oxford Nanopore instruments. Assembly of the combined data produced a genome of 2.74 Gbp in total length, with an N50 contig size of 1,094,236 bp. To annotate the genome, we mapped the genes from another M. monax genome and from the closely related Alpine marmot, Marmota marmota, onto our assembly, resulting in 20,559 annotated protein-coding genes and 28,135 transcripts. The genome assembly and annotation are available in GenBank under BioProject PRJNA587092.


Subject(s)
Marmota , Nanopores , Animals , Base Sequence , Genome , High-Throughput Nucleotide Sequencing , Marmota/genetics , United States
7.
Chem Commun (Camb) ; 56(56): 7745-7748, 2020 Jul 18.
Article in English | MEDLINE | ID: mdl-32579619

ABSTRACT

Circularly polarized luminescence controlled by both mechanics and temperature was observed for the first time. The cyano-distyrylbenzene-cholesterol liquid crystals exhibited not only mechanochromism and thermochromism but also mechanically induced and thermally induced circularly polarized.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117916, 2020 Mar 15.
Article in English | MEDLINE | ID: mdl-31839575

ABSTRACT

This work designed and synthesized the first organic fluorescent sensor for curcumin in aqueous media based on red-to-green fluorescence change of acylhydrazone-bridged bis-tetraphenylethylene (Bis-TPE). Bis-TPE was prepared by condensation of formyltetraphenylethylene with dihydrazide oxalate in 86% yield. It has the large conjugated electron effect with strong red AIE fluorescence in aqueous solution. It displayed high selective sensing ability for curcumin with red-to-green fluorescence change in THF-H2O (5:95). The detection limit was as low as 1.15 × 10-7 M. The sensing mechanism was confirmed as 1:1 stoichiometric ratio based on quadruple hydrogen bonds. Bis-TPE was successfully applied for analyzing curcumin of ginger and living cell imaging, supplying a new detecting strategy for curcumin in real sample and living environment.


Subject(s)
Curcumin/analysis , Fluorescent Dyes , Stilbenes/chemistry , Fluorescent Dyes/chemical synthesis , Fluorescent Dyes/chemistry , Limit of Detection , Spectrometry, Fluorescence , Water/chemistry
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 227: 117568, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31654844

ABSTRACT

Although all kinds of sensors with unique detecting ability for one guest were reported, the fluorescence sensor with multiple detecting abilities was seldom presented. This work designed and synthesized a novel AIE fluorescence probe bearing double detecting for ATP based on Cu2+ and Zn2+ response of hydrazono-bis-tetraphenylethylene (Bis-TPE). Bis-TPE was prepared in 82% yield with simple procedure. It exhibited strong red AIE fluorescence based on the large conjugated electron effect in aqueous media. It showed outstanding selective sensing abilities for Cu2+ by strong fluorescence quenching and for Zn2+ by red-orange fluorescence change. The sensing mechanism of 1:1 stoichiometric ratios was confirmed by 1H NMR and MS study. The strong red fluorescence of Bis-TPE + Cu2+ system could be recovered by adding ATP. The orange fluorescence of Bis-TPE + Zn2+ system could be quenched by adding Cu2+ and then was recovered by adding ATP. These double detecting abilities for ATP with the "off-on" red fluorescence in Bis-TPE + Cu2+ system and "allochroic-off-on" orange fluorescence in Bis-TPE + Zn2++Cu2+ system were successfully applied to test Cu2+, Zn2+ and ATP in test paper and living cell imaging, displaying the good application prospects for sensing Cu2+, Zn2+ and double detecting ATP in the complicated environment.

10.
Analyst ; 144(8): 2662-2669, 2019 Apr 08.
Article in English | MEDLINE | ID: mdl-30843902

ABSTRACT

Aggregation-induced emission (AIE) provides a new strategy for preparing fluorescent sensors in aggregated state. In this paper, a series of crown ether-bridged bis-tetraphenylethylene compounds were synthesized in 78-84% yield by a simple procedure. The molecules exhibited excellent AIE properties in THF/H2O solutions and solid films. The investigation on sensing abilities for various biomolecules and metal ions suggested that Bis-TPE-1 possessed obvious response to folic acid, with fluorescence enhancement and blue shift of maximum emission wavelength from 380 nm to 365 nm. The detection limit for folic acid was 6.36 × 10-7 M, and the sensor's selectivity for folic acid was little interfered by the other species. The sensor mechanism was studied by FT-IR, 1H NMR, MS spectra and fluorescence Jobs' plot. The selective sensor for folic acid was applied in test paper and the analyses of real samples of mung bean and spinach. The superior bioimaging performance of Bis-TPE-1 for sensing folic acid was confirmed by the live cell imaging experiments, which indicated its good practical application potential for detecting folic acid.


Subject(s)
Crown Ethers/chemistry , Fluorescent Dyes/chemistry , Folic Acid/analysis , Stilbenes/chemistry , Crown Ethers/chemical synthesis , Fluorescence , Fluorescent Dyes/chemical synthesis , HeLa Cells , Humans , Hydrogen-Ion Concentration , Limit of Detection , Microscopy, Confocal/methods , Microscopy, Fluorescence/methods , Spectrometry, Fluorescence/methods , Spinacia oleracea/chemistry , Stilbenes/chemical synthesis , Vigna/chemistry
11.
Analyst ; 143(18): 4298-4305, 2018 Sep 10.
Article in English | MEDLINE | ID: mdl-30095834

ABSTRACT

Aggregation-induced emission (AIE) molecules eliminate the aggregation-caused quenching (ACQ) phenomenon effectively and exhibit excellent properties of a fluorescent sensor in the aggregated state. In this paper, an allochroic fluorescent sensor based on AIE molecules with a diphenylacrylonitrile structure was prepared in high yield by a simple procedure. This molecule possessed good AIE properties and exhibited a sensitive sensor ability for aliphatic amines with an obvious color change from orange to blue-green. The detailed investigation on the detection of hydrazine suggested that the detection limit for hydrazine was 3.67 × 10-6 M, and the highly sensitive sensor for hydrazine was not influenced by other species. The sensor mechanism was confirmed by using 1H NMR and MS spectra. The sensor for hydrazine was successfully applied in a test paper, exhibiting good practical application potential for detecting hydrazine. The experiment of living cell imaging suggested that this sensor showed superior bioimaging performance and presented sensitive detection for hydrazine with an obvious color change from orange to blue-green.


Subject(s)
Fluorescent Dyes , Hydrazines/analysis , Optical Imaging , Humans , Limit of Detection , MCF-7 Cells , Microscopy, Confocal
12.
MAbs ; 10(6): 913-921, 2018.
Article in English | MEDLINE | ID: mdl-29953319

ABSTRACT

Immunomodulatory monoclonal IgG1 antibodies developed for cancer and autoimmune disease have an inherent risk of systemic release of pro-inflammatory cytokines. In vitro cytokine release assays are currently used to predict cytokine release syndrome (CRS) risk, but the validation of these preclinical tools suffers from the limited number of characterized CRS-inducing IgG1 antibodies and the poor understanding of the mechanisms regulating cytokine release. Here, we incubated human whole blood from naïve healthy volunteers with four monoclonal IgG1 antibodies with different proven or predicted capacity to elicit CRS in clinic and measured cytokine release using a multiplex assay. We found that, in contrast to anti-CD52 antibodies (Campath-1H homolog) that elicited high level of multiple inflammatory cytokines from human blood cells in vitro, other IgG1 antibodies with CRS-inducing potential consistently induced release of a single tested cytokine, interferon (IFN)-γ, with a smaller magnitude than Campath. IFN-γ expression was observed as early as 2-4 h after incubation, mediated by natural killer cells, and dependent upon tumor necrosis factor and FcγRIII. Importantly, the magnitude of the IFN-γ response elicited by IgG1 antibodies with CRS-inducing potential was determined by donor FcγRIIIa-V158F polymorphism. Overall, our results highlight the importance of FcγRIIIa-dependent IFN-γ release in preclinical cytokine release assay for the prediction of CRS risk associated with therapeutic IgG1 antibodies.


Subject(s)
Antibodies, Monoclonal/immunology , Immunoglobulin G/immunology , Interferon-gamma/immunology , Receptors, IgG/immunology , Alemtuzumab/immunology , Alemtuzumab/therapeutic use , Antibodies, Monoclonal/therapeutic use , Cytokines/blood , Cytokines/immunology , Cytokines/metabolism , Humans , Immunoassay/methods , Immunoglobulin G/therapeutic use , Interferon-gamma/blood , Interferon-gamma/metabolism , Neoplasms/drug therapy , Neoplasms/immunology , Polymorphism, Genetic/immunology , Prognosis , Receptors, IgG/genetics , Syndrome
13.
Zhongguo Zhong Yao Za Zhi ; 33(7): 813-5, 2008 Apr.
Article in Chinese | MEDLINE | ID: mdl-18589789

ABSTRACT

OBJECTIVE: The present study investigated the inhibitory effects of Chinese herb component sinapine on activity of acetylcholinesterase (AChE) in cerebral homogenate and blood serum of rats. METHOD: AChE was prepared from cerebral homogenate and blood serum of rats, respectively. Acetylcholinesterase activity assay kit and Chromatometry were used to detect the AChE activity. RESULT: Sinapine significantly inhibited AChE activity in vitro, with more effective on cerebral homogenate (IC50 3.66 micromol x L(-1)) than blood serum (IC50 22.1 micromol x L(-1)). CONCLUSION: Sinapine could significantly inhibit the cerebral AChE activity and may be a promising drug used for prevention and cure of Alzheimer's disease as a cholinesterase inhibitor.


Subject(s)
Acetylcholinesterase/blood , Acetylcholinesterase/metabolism , Brain/enzymology , Choline/analogs & derivatives , Cholinesterase Inhibitors/pharmacology , Alzheimer Disease/drug therapy , Alzheimer Disease/prevention & control , Animals , Brain/cytology , Choline/pharmacology , Choline/therapeutic use , Cholinesterase Inhibitors/therapeutic use , Rats
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