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1.
Front Pharmacol ; 13: 800885, 2022.
Article in English | MEDLINE | ID: mdl-35140614

ABSTRACT

The prediction of the estrogen receptor (ER) and androgen receptor (AR) activity of a compound is quite important to avoid the environmental exposures of endocrine-disrupting chemicals. The Estrogen and Androgen Receptor Database (EARDB, http://eardb.schanglab.org.cn/) provides a unique collection of reported ERα, ERß, or AR protein structures and known small molecule modulators. With the user-uploaded query molecules, molecular docking based on multi-conformations of a single target will be performed. Moreover, the 2D similarity search against known modulators is also provided. Molecules predicted with a low binding energy or high similarity to known ERα, ERß, or AR modulators may be potential endocrine-disrupting chemicals or new modulators. The server provides a tool to predict the endocrine activity for compounds of interests, benefiting for the ER and AR drug design and endocrine-disrupting chemical identification.

2.
J Am Chem Soc ; 142(41): 17756-17765, 2020 Oct 14.
Article in English | MEDLINE | ID: mdl-33021373

ABSTRACT

This work describes a strategy to produce circularly polarized thermally activated delayed fluorescence (CP-TADF). A set of two structurally similar organic emitters SFST and SFOT are constructed, whose spiro architectures containing asymmetric donors result in chirality. Upon grafting within the spiro frameworks, the donor and acceptor are fixed proximally in a face-to-face manner. This orientation allows intramolecular through-space charge transfer (TSCT) to occur in both emitters, leading to TADF properties. The donor units in SFST and SFOT have a sulfur and oxygen atom, respectively; such a subtle difference has great impacts on their photophysical, chiroptical, and electroluminescence (EL) properties. SFOT exhibits greatly enhanced EL performance in doped organic light-emitting diodes, with external quantum efficiency (EQE) up to 23.1%, owing to the concurrent manipulation of highly photoluminescent quantum efficiency (PLQY, ∼90%) and high exciton utilization. As a comparison, the relatively larger sulfur atom in SFST introduces heavy atom effects and leads to distortion of the molecular backbone that lengthens the donor-acceptor distance. SFST thus has lower PLQY and faster nonradiative decay rate. The collective consequence is that the EQE value of SFST, i.e., 12.5%, is much lower than that of SFOT. The chirality of these two spiro emitters results in circularly polarized luminescence. Because SFST has a more distorted molecular architecture than SFOT, the luminescence dissymmetry factor (|glum|) of circularly polarized luminescence of one enantiomer of the former, namely, either (S)-SFST or (R)-SFST, is almost twice that of (S)-SFOT/(R)-SFOT. Moreover, the CP organic light-emitting diodes (CP-OLEDs) show obvious circularly polarized electroluminescence (CPEL) signals with gEL of 1.30 × 10-3 and 1.0 × 10-3 for (S)-SFST and (S)-SFOT, respectively.

3.
Adv Mater ; 32(48): e2003885, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33118645

ABSTRACT

In this work, two novel thermally activated delayed fluorescence (TADF) emitters, 2tDMG and 3tDMG, are synthesized for high-efficiency organic light-emitting diodes (OLEDs), The two emitters have a tilted face-to-face alignment of donor (D)/acceptor (A) units presenting intramolecular noncovalent interactions. The two TADF materials are deposited either by an evaporation-process or by a solution-process, both of them leading to high OLED performance. 2tDMG used as the emitter in evaporation-processed OLEDs achieves a high external quantum efficiency (EQE) of 30.8% with a very flat efficiency roll-off of 7% at 1000 cd m-2 . The solution-processed OLEDs also display an interesting EQE of 16.2%. 3tDMG shows improved solubility and solution processability as compared to 2tDMG, and thus a high EQE of 20.2% in solution-processed OLEDs is recorded. The corresponding evaporation-processed OLEDs also reach a reasonably high EQE of 26.3%. Encouragingly, this work provides a novel strategy to address the imperious demands for OLEDs with high EQE and low roll-off.

4.
J Org Chem ; 85(16): 10628-10637, 2020 Aug 21.
Article in English | MEDLINE | ID: mdl-32806105

ABSTRACT

Intramolecular spatial charge transfer (ISCT) plays a critical role in determining the optical and charge transport properties of thermally activated delayed fluorescence (TADF) materials. Herein, a new donor/acceptor-type TADF compound based on rigid dibenzothiophene sulfone (DBTS) moiety, STF-DBTS, was designed and synthesized. Fluorene unit was used as a rigid linker to position the rigid acceptor and donor subunit in close vicinity with control over their spacing and molecular structure and to achieve high photoluminescence quantum yield (∼53%) and TADF property. For comparison purposes, we constructed the more flexible STF-DPS with a less rotationally constrained diphenylsulphone (DPS) acceptor instead of the rigid DBTS units, and STF-DPS showed no TADF properties and lower PLQY (16.0%). Organic light-emitting diodes (OLEDs) based on STF-DBTS achieve an external quantum efficiency (EQE) of 10.3% at 488 nm, which is a fivefold improvement in EQE with respect to STF-DPS.

5.
Nat Mater ; 19(12): 1332-1338, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32541938

ABSTRACT

Charge-transfer (CT) complexes, formed by electron transfer from a donor to an acceptor, play a crucial role in organic semiconductors. Excited-state CT complexes, termed exciplexes, harness both singlet and triplet excitons for light emission, and are thus useful for organic light-emitting diodes (OLEDs). However, present exciplex emitters often suffer from low photoluminescence quantum efficiencies (PLQEs), due to limited control over the relative orientation, electronic coupling and non-radiative recombination channels of the donor and acceptor subunits. Here, we use a rigid linker to control the spacing and relative orientation of the donor and acceptor subunits, as demonstrated with a series of intramolecular exciplex emitters based on 10-phenyl-9,10-dihydroacridine and 2,4,6-triphenyl-1,3,5-triazine. Sky-blue OLEDs employing one of these emitters achieve an external quantum efficiency (EQE) of 27.4% at 67 cd m-2 with only minor efficiency roll-off (EQE = 24.4%) at a higher luminous intensity of 1,000 cd m-2. As a control experiment, devices using chemically and structurally related but less rigid emitters reach substantially lower EQEs. These design rules are transferrable to other donor/acceptor combinations, which will allow further tuning of emission colour and other key optoelectronic properties.

6.
Org Lett ; 21(13): 5281-5284, 2019 Jul 05.
Article in English | MEDLINE | ID: mdl-31247763

ABSTRACT

Two novel donor-σ-π-σ-acceptor-type dispiro molecules-10-phenyl-10H-dispiro-acridine-9,9'-anthracene-10',9''-fluorene-2'',7''-dicarbo-nitrile (DiSAAF) and dispiro-fluorene-9,9'-anthracene-10',9''-quinolino[3,2,1-kl]phenoxazine-2,7-dicarbonitrile (DiSFAQ)-with excellent thermal stability are designed and synthesized. Both materials exhibit blocked long-range intramolecular charge transfer but show intermolecular charge-transfer emission in the film state. Their photophysical and thermal properties then are fully investigated and a maximum external quantum efficiency of 21.7% of the red phosphorescent device is achieved by DiSAAF.

7.
Angew Chem Int Ed Engl ; 58(12): 3848-3853, 2019 Mar 18.
Article in English | MEDLINE | ID: mdl-30762276

ABSTRACT

Reported here are C1-linked spiro-bifluorene dimers. A comprehensive study is carried out to analyze the electronic properties of these highly twisted structures. This work shows that the C1-position enables the design of pure hydrocarbon materials, with a high triplet energy, for hosting blue phosphors in efficient phosphorescent OLEDs (PhOLEDs). To date, this work describes the highest performance of blue PhOLEDs ever reported for pure hydrocarbons (external quantum efficiency of ca. 23 %), thus highlighting the potential of the C1-spirobifluorene scaffold in organic electronics.

8.
ACS Appl Mater Interfaces ; 10(35): 29840-29847, 2018 Sep 05.
Article in English | MEDLINE | ID: mdl-30095891

ABSTRACT

How to maintain high power efficiency (PE) and color stability under operating brightness is critical for the white organic light-emitting diodes (WOLEDs). To this end, two novel spiro-type materials STPy3 and STPy4 were designed. These materials could act as a single host and achieve a remarkable external quantum efficiency of 27.5% at 1000 cd m-2; to further optimize the PEs of OLEDs, STPy3/4 and PO-T2T were used as co-host-induced exciplexes, which enhanced the PE of green OLED to over 148.0 lm W-1. Unfortunately, the lower triplet energy level of exciplexes than blue emitters implied it is commonly unsuitable to fabricate WOLEDs. Herein, a new allocation of gradient exciplex (AGE) strategy was developed in which the formed excitons could be rationally allocated in a consequently doped nonuniform profile. The AGE incorporated the advantages of the exciplex with an ultralow turn-on voltage of 2.3 V and efficiency stability of spiro materials. The PE at 1000 cd m-2 was enhanced to 72.7 lm W-1, representing the first exciplex WOLED with the performance exceeding that of conventional fluorescent tubes.

9.
Huan Jing Ke Xue ; 39(4): 1910-1917, 2018 Apr 08.
Article in Chinese | MEDLINE | ID: mdl-29965018

ABSTRACT

An in-situ paddy field experiment was carried out to study the influence of a tribasic amendment (QFJ, hydroxyapatite+zeolite+biochar) on Cd and As accumulation and translocation in rice grown in soil contaminated with cadmium and arsenic, with the concentrations of soil Cd and As being 3.58 mg·kg-1 and 124.79 mg·kg-1, respectively. The results showed that, after application of QFJ, the pH, CEC, and OM contents of the rice rhizosphere soil tended to increase. The exchangeable concentrations of Cd and As were reduced from 0.37 mg·kg-1 and 0.07 mg·kg-1 to 0.12 mg·kg-1 and 0.04 mg·kg-1, respectively. The concentrations of Cd and As in rice tissues decreased after in-situ restoration. When 9.00 t·hm-2 of QFJ was applied, the Cd concentration in brown rice was reduced from 0.46 to 0.18 mg·kg-1, and that of inorganic As was reduced from 0.25 to 0.16 mg·kg-1, both lower than 0.2 mg·kg-1, meeting the requirement set by the National Food Standards (GB 2762-2012). QFJ application decreased the Cd and As bioaccumulation capacity of the roots and decreased the rice plant's capacity of Cd translocation quantity from the underground parts to the aerial parts; at same time, the Cd transferring capacity of the roots and the As transferring capacity in straw and husk were also decreased.


Subject(s)
Arsenic/analysis , Cadmium/analysis , Oryza/chemistry , Soil Pollutants/analysis , Charcoal , Durapatite , Soil , Zeolites
10.
Am J Chin Med ; 38(6): 1093-106, 2010.
Article in English | MEDLINE | ID: mdl-21061463

ABSTRACT

Cordyceps militaris (L.) Link is an entomopathogenic fungus parasitic to Lepidoptera larvae, and is widely used as a folk tonic or invigorant for longevity in China. Although C. militaris has been used in traditional Chinese medicine for millennia, there is still a lack convincing evidence for its anti-aging activities. This study was performed to investigate the effects of polysaccharides from cultivated fruiting bodies of C. militaris (CMP) on mitochondrial injury, antioxidation and anti-aging activity. Fruiting bodies of C. militaris were cultivated artificially under optimized conditions. The spectrophotometric method was used to measure thiobarbituric acid reactive substances (TBARS), mitochondrial swelling, and activities of scavenging superoxide anions in vitro. D-galactose (100 mg/kg/day) was injected subcutaneously into back of the neck of mice for 7 weeks to induce an aging model. The effects of CMP on the activities of catalase (CAT), surperoxide dismutase (SOD), glutathione peroxidase (GPx) and anti-hydroxyl radicals were assayed in vivo using commercial monitoring kits. The results showed that CMP could inhibit mitochondrial injury and swelling induced by Fe²(+)-L-Cysteine in a concentration- dependent manner and it also had a significant superoxide anion scavenging effect. Moreover, the activities of CAT, SOD, GPx and anti-hydroxyl radicals in mice liver were increased significantly by CMP. These results indicate that CMP protects mitochondria by scavenging reactive oxygen species (ROS), inhibiting mitochondrial swelling, and increasing the activities of antioxidases. Therefore, CMP may have pharmaceutical values for mitochondrial protection and anti-aging. CMP was the major bioactive component in C. militaris.


Subject(s)
Aging/drug effects , Antioxidants/therapeutic use , Cordyceps/chemistry , Liver/drug effects , Mitochondria/drug effects , Mitochondrial Diseases/drug therapy , Polysaccharides/therapeutic use , Aging/physiology , Animals , Antioxidants/metabolism , Antioxidants/pharmacology , Cysteine , Disease Models, Animal , Dose-Response Relationship, Drug , Fruiting Bodies, Fungal , Galactose , Hydroxyl Radical/metabolism , Injections, Subcutaneous , Liver/metabolism , Male , Mice , Mice, Inbred Strains , Mitochondria/metabolism , Mitochondria/pathology , Mitochondrial Diseases/metabolism , Mitochondrial Diseases/pathology , Phytotherapy , Polysaccharides/pharmacology , Reactive Oxygen Species/metabolism , Superoxides/metabolism , Thiobarbituric Acid Reactive Substances
11.
J Chromatogr A ; 1216(35): 6259-66, 2009 Aug 28.
Article in English | MEDLINE | ID: mdl-19632683

ABSTRACT

By using ionic liquid as membrane liquid and tri-n-octylphosphine oxide (TOPO) as additive, hollow fiber supported liquid phase microextraction (HF-LPME) was developed for the determination of five sulfonamides in environmental water samples by high-performance liquid chromatography with ultraviolet detection The extraction solvent and the parameters affecting the extraction enrichment factor such as the type and amount of carrier, pH and volume ratio of donor phase and acceptor phase, extraction time, salt-out effect and matrix effect were optimized. Under the optimal extraction conditions (organic liquid membrane phase: [C(8)MIM][PF(6)] with 14% TOPO (w/v); donor phase: 4mL, pH 4.5 KH(2)PO(4) with 2M Na(2)SO(4); acceptor phase: 25microL, pH 13 NaOH; extraction time: 8 h), low detection limits (0.1-0.4microg/L, RSDor=0.999) were obtained for all the analytes. The presence of humic acid (0-25mg/L dissolved organic carbon) and bovine serum albumin (0-100microg/mL) had no significant effect on the extraction efficiency. Good spike recoveries over the range of 82.2-103.2% were obtained when applying the proposed method on five real environmental water samples. These results indicated that this present method was very sensitive and reliable with good repeatabilities and excellent clean-up in water samples. The proposed method confirmed hollow fiber supported ionic liquid membrane based LPME to be robust to monitoring trace levels of sulfadiazine, sulfamerazine, sulfamethazine, sulfadimethoxine and sulfamethoxazole in aqueous samples.


Subject(s)
Anti-Bacterial Agents/analysis , Chemical Fractionation/methods , Ionic Liquids , Sulfonamides/analysis , Water Pollutants, Chemical/analysis , Analytic Sample Preparation Methods , Anti-Bacterial Agents/isolation & purification , Calibration , Chromatography, High Pressure Liquid , Fresh Water/chemistry , Hydrogen-Ion Concentration , Imidazoles , Industrial Waste , Organophosphorus Compounds , Osmolar Concentration , Solvents , Sulfonamides/isolation & purification , Time Factors
12.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-325419

ABSTRACT

The Arabidopsis thaliana tonoplast Na+ /H+ antiporter gene, AtNHX1, was transferred into buckwheat by Agrobacterium-mediated method. Transgenic buckwheat plants were regenerated and selected on MS basal medium supplemented with 2.0mg/L 6-BA, 1.0mg/L KT, 0.lmg/L IAA, 50mg/L kanamycin and 500mg/L carbenicillin. 426 seedlings from 36 resistant calli originated from 864 explants (transformed about at 4.17 percentage) exhibited resistance to kanamycin. The transformants were confirmed by PCR, Southern blotting, RT-PCR and Northern blotting analysis. After stress treatment for 6 weeks with 200mmol/L NaCl, transgenic plants survived, while wild-type plants did not. After 3 days of stress treatment through different concentrations of NaCl, transgenic plants accumulated higher concentration of Na+ and proline than the control plants. However, the K+ concentration of transgenic plants declined in comparison with the control plants. Moreover, the rutin content of the roots, stems and leaves of transgenic buckwheat increased than those of the control plants. These results showed that it could be possible to improve the salt-tolerance of crops with genetic technology.


Subject(s)
Adaptation, Physiological , Genetics , Physiology , Arabidopsis Proteins , Genetics , Physiology , Blotting, Northern , Blotting, Southern , Cation Transport Proteins , Genetics , Physiology , Fagopyrum , Genetics , Metabolism , Physiology , Plant Roots , Genetics , Metabolism , Physiology , Plant Stems , Genetics , Metabolism , Physiology , Plants, Genetically Modified , Genetics , Metabolism , Physiology , Potassium , Metabolism , Proline , Metabolism , Regeneration , Reverse Transcriptase Polymerase Chain Reaction , Rutin , Metabolism , Sodium , Metabolism , Sodium Chloride , Pharmacology , Sodium-Hydrogen Exchangers , Genetics , Physiology , Transformation, Genetic
13.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-269909

ABSTRACT

<p><b>OBJECTIVE</b>To observe the effect of vertebral manipulation (VM) therapy on vertebro-basilar artery (VBA) blood flow in patients with cervical spondylosis of vertebral artery type (CS-VAT) by transcranial Doppler (TCD) ultrasonic examination.</p><p><b>METHODS</b>One hundred and fifty patients with CS-VAT were randomized into the VM group (n = 100) and the acupuncture group (n = 50), and treated for ten times as one therapeutic course. Changes of the contraction peak, the end-diastolic and average blood flow velocity of VBA before and after treatment in the two groups were observed and compared by TCD.</p><p><b>RESULTS</b>Vp, Vd, Vm of LVA, RVA and BA in the two groups after treatment were all lowered, showing significant difference, excepting Vp of VBA in the acupuncture group, when compared with before treatment (P< 0.05 or P <0.01). Comparison between the two groups after treatment showed significant difference in Vp and Vm of LVA, Vp, Vd and Vm of RVA, Vp and Vm of VBA respectively (P<0.05, P <0.01).</p><p><b>CONCLUSION</b>VM therapy in treating patients with CS-VAT shows therapeutic effect superior to VA therapy, which could significantly improve VBA blood flow.</p>


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Basilar Artery , Blood Flow Velocity , Cervical Vertebrae , Manipulation, Spinal , Methods , Spinal Osteophytosis , Therapeutics , Vertebral Artery , Vertebrobasilar Insufficiency , Therapeutics
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