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1.
J Am Chem Soc ; 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853354

RESUMO

A piezoelectric polymer membrane based on single metal atoms was demonstrated to be effective by anchoring isolated calcium (Ca) atoms on a composite of nitrogen-doped carbon and polyvinylidene fluoride (PVDF). The addition of Ca-atom-anchored carbon nanoparticles not only promotes the formation of the ß phase (from 29.8 to 56.3%), the most piezoelectrically active phase, in PVDF, but also introduces much higher porosity and hydrophilicity. Under ultrasonic excitation, the fabricated catalyst membrane demonstrates a record-high and stable dye decomposing rate of 0.11 min-1 and antibacterial efficiencies of 99.8%. Density functional theory calculations reveal that the primary contribution to catalytic activity arises from single-atom Ca doping and that a possible synergistic effect between PVDF and Ca atoms can improve the catalytic performance. It is shown that O2 molecules can be easily hydrogenated to produce ·OH on Ca-PVDF, and the local electric field provided by the ß-phase-PVDF might enhance the production of ·O2-. The proposed polymer membrane is expected to inspire the rational design of piezocatalysts and pave the way for the application of piezocatalysis technology for practical environmental remediation.

2.
Plants (Basel) ; 13(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38475433

RESUMO

As one of the most prominent gene families, R2R3-MYB transcription factors significantly regulate biochemical and physiological processes under salt stress. However, in Sophora alopecuroides, a perennial herb known for its exceptional saline alkali resistance, the comprehensive identification and characterization of SaR2R3-MYB genes and their potential functions in response to salt stress have yet to be determined. We investigated the expression profiles and biological functions of SaR2R3-MYB transcription factors in response to salt stress, utilizing a transcriptome-wide mining method. Our analysis identified 28 SaR2R3-MYB transcription factors, all sharing a highly conserved R2R3 domain, which were further divided into 28 subgroups through phylogenetic analysis. Some SaR2R3-MYB transcription factors showed induction under salt stress, with SaR2R3-MYB15 emerging as a potential regulator based on analysis of the protein-protein interaction network. Validation revealed the transcriptional activity and nuclear localization of SaR2R3-MYB15. Remarkably, overexpression of SaR2R3-MYB15 in transgenic plants could increase the activity of antioxidant enzymes and the accumulation of proline but decrease the content of malondialdehyde (MDA), compared with wild-type plants. Moreover, several salt stress-related genes showed higher expression levels in transgenic plants, implying their potential to enhance salt tolerance. Our findings shed light on the role of SaR2R3-MYB genes in salt tolerance in S. alopecuroides.

3.
Int J Biol Sci ; 19(11): 3360-3382, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37496997

RESUMO

Targeted therapies in cancer treatment can improve in vivo efficacy and reduce adverse effects by altering the tissue exposure of specific biomolecules. However, there are still large number of target proteins in cancer are still undruggable, owing to the following factors including (1) lack of ligand-binding pockets, (2) function based on protein-protein interactions (PPIs), (3) the highly specific conserved active sites among protein family members, and (4) the variability of tertiary docking structures. The current status of undruggable targets proteins such as KRAS, TP53, C-MYC, PTP, are carefully introduced in this review. Some novel techniques and drug designing strategies have been applicated for overcoming these undruggable proteins, and the most classic and well-known technology is proteolysis targeting chimeras (PROTACs). In this review, the novel drug development strategies including targeting protein degradation, targeting PPI, targeting intrinsically disordered regions, as well as targeting protein-DNA binding are described, and we also discuss the potential of these strategies for overcoming the undruggable targets. Besides, intelligence-assisted technologies like Alpha-Fold help us a lot to predict the protein structure, which is beneficial for drug development. The discovery of new targets and the development of drugs targeting them, especially those undruggable targets, remain a huge challenge. New drug development strategies, better extraction processes that do not disrupt protein-protein interactions, and more precise artificial intelligence technologies may provide significant assistance in overcoming these undruggable targets.


Assuntos
Inteligência Artificial , Neoplasias , Humanos , Proteínas/metabolismo , Proteólise , Neoplasias/tratamento farmacológico , Descoberta de Drogas
4.
J Colloid Interface Sci ; 646: 687-694, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37229986

RESUMO

The photoelectrochemical (PEC) performance of bismuth vanadate (BiVO4) suffers from sluggish charge mobility and substantial charge recombination losses due to its intrinsic defect. To rectify the problem, we developed a novel approach to prepare an n-n+ type II BVOac-BVOal homojunction with staggered band alignment. This architecture involves a built-in electric field that facilitating the electron-hole separation at the BVOac/BVOal interface. As a result, the BVOac-BVOal homojunction shows superior photocurrent density up to 3.6 mA/cm2 at 1.23 V vs. reversible hydrogen electrode (RHE) with 0.1 M sodium sulfite as the hole scavenger, which is 3 times higher than that of the single-layer BiVO4 photoanode. Unlike the previous efforts that modifying the PEC performance of BiVO4 photoanodes through incorporating heteroatoms, the highly-efficient BVOac-BVOal homojunction was achieved without incorporating any heteroatoms in this work. The remarkable PEC activity of the BVOac-BVOal homojunction highlights the tremendous importance of reducing the charge recombination rate at the interface by constructing the homojunction and offers an effective strategy to form the heteroatoms-free BiVO4 thin film as an efficient photoanode material for practical PEC applications.

5.
Front Pharmacol ; 14: 1127931, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37006994

RESUMO

Inhibition of epithelial ferroptosis in colonic tissues relieved clinical symptoms and improved endoscopic presentations in inflammatory bowel disease (IBD). Kumatakenin, the main ingredient of traditional Chinese medicinal cloves and Alpinia purpurata, is reported to possess therapeutic benefits. However, whether kumatakenin could inhibit ferroptosis and further alleviate colitis remains unclear. Here, we measured the effects of kumatakenin on ferroptosis of colonic epithelial cells from colitis mice. The colitis model was induced in mice by oral intake of 2.5% dextran sulfate sodium in drinking water. RNA sequencing was performed to investigate the mechanism underlying kumatakenin-mediated effects on colitis. The results showed that different doses of kumatakenin significantly alleviated symptoms and suppressed intestinal inflammation in the colitis mouse model. Kumatakenin supplementation decreased cellular iron levels and suppressed ferroptosis in epithelial cells from colitis mice. RNA sequencing, qPCR, and pharmacological inhibition assays showed that kumatakenin reduced cellular iron levels and suppressed ferroptosis in epithelial cells from colitis mice at least partially by upregulating expression of enolase (Eno-3). Furthermore, kumatakenin decreased iron levels in epithelial cells by modulating the Eno3-iron regulatory protein (IRP1) axis. Molecular docking results revealed that kumatakenin could bind Eno3 via hydrogen bonding with the amino acid residues Thr208, Val206, and Pro203. This work will provide a scientific basis for the clinical use of kumatakenin in the treatment of colitis.

7.
Biomed Pharmacother ; 157: 114081, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36481399

RESUMO

Crohn's disease (CD) and ulcerative colitis (UC), the two main forms of inflammatory bowel disease (IBD), are chronic, systemic autoimmune diseases. As the incidence of IBD rapidly increases in Asia, increasing attention has been paid to developing additional treatment strategies. Presently, the end point of therapy is achieving clinical and endoscopic remission through the blockade of inflammatory cascades. Recent studies have shown that monoclonal antibodies (mAbs) use for precise molecular targeting of inflammatory pathways has a promising effect on IBD, especially moderate-to-severe CD and UC. Since the 1997 report on the use of infliximab (a monoclonal antibody against tumor necrosis factor alpha [TNF-α]) in patients with CD, mAbs have expanded therapeutic options and have also complicated initial management options and subsequent treatment. This review comprehensively summarizes the clinical reports and studies related to the use of mAbs for the treatment of IBD in Asian countries and regions in recent years thus demonstrating the current status of mAbs use in Asia. In addition, the differences in the use of mAbs for the treatment of IBD between the Asia and the West are expounded. Ultimately, it is hoped that this review will provide new insights and a scientific basis for the clinical application of mAbs.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Humanos , Anticorpos Monoclonais/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/epidemiologia , Infliximab/uso terapêutico , Doença de Crohn/tratamento farmacológico , Doença de Crohn/patologia , Colite Ulcerativa/tratamento farmacológico
8.
Food Funct ; 13(18): 9470-9480, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-35983876

RESUMO

Inhibition of ferroptosis in intestinal epithelial cells ameliorates clinical symptoms and improves endoscopic presentations in inflammatory bowel disease (IBD). Licorice is used worldwide in food and medicine fields. Liquiritin, a flavonoid component in licorice, is an effective substance used as an anti-inflammatory, antioxidant food that has been shown to improve chemically induced colitis. Herein we evaluated the therapeutic effects of liquiritin on colitis and determined whether liquiritin could affect colitis by modulating ferroptosis in epithelial cells. A colitis model was induced in mice by oral administration with 2.5% DSS dissolved in drinking water. The results showed that liquiritin significantly alleviated symptoms, suppressed intestinal inflammation and restored the epithelial barrier function in the colitis mouse model. Liquiritin supplementation upregulated colonic ferritin expression, increased the storage of cellular iron, reduced the cellular iron level and further inhibited ferroptosis in epithelial cells from the colitis model. Pharmacological stimulation of ferroptosis largely blocked liquiritin-induced alleviation of colitis. Peroxiredoxin-6 (Prdx6) expression was significantly decreased in the DSS group, which was reversed by liquiritin treatment. Genetic or pharmacological silencing of Prdx6 largely reversed liquiritin-induced modulation of the ferritin/iron level and ferroptosis in epithelial cells. Molecular docking results showed that liquiritin could bind to Prdx6 through the hydrogen bond interaction with amino acid residues Thr208, Val206 and Pro203. In conclusion, liquiritin treatment largely alleviated DSS induced colitis by inhibiting ferroptosis in epithelial cells. Liquiritin negatively regulated ferroptosis in epithelial cells in colitis by activating Prdx6, increasing the expression of ferritin and subsequently reducing the cellular iron level.


Assuntos
Colite , Ferroptose , Flavanonas , Peroxirredoxina VI , Aminoácidos/metabolismo , Animais , Anti-Inflamatórios/metabolismo , Antioxidantes/metabolismo , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/genética , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Ferritinas/metabolismo , Flavanonas/farmacologia , Glucosídeos/farmacologia , Ferro/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Peroxirredoxina VI/metabolismo
9.
iScience ; 25(4): 104111, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35402887

RESUMO

We report a combined experimental and theoretical study on intriguing magnetic properties of quasiferroelectric orthochromates. Large single crystals of the family of RECrO3 (RE = Y, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) compounds were successfully grown. Neutron Laue study indicates a good quality of the obtained single crystals. Applied magnetic field and temperature dependent magnetization measurements reveal their intrinsic magnetic properties, especially the antiferromagnetic (AFM) transition temperatures. Density functional theory studies of the electronic structures were carried out using the Perdew-Burke-Ernzerhof functional plus Hubbard U method. Crystallographic information and magnetism were theoretically optimized systematically. When RE3+ cations vary from Y3+ and Eu3+ to Lu3+ ions, the calculated t-e orbital hybridization degree and Néel temperature behave similarly to the experimentally determined AFM transition temperature with variation in cationic radius. We found that the t-e hybridization is anisotropic, causing a magnetic anisotropy of Cr3+ sublattices. This was evaluated with the nearest-neighbor J 1-J 2 model. Our research provides a picture of the electronic structures during the t-e hybridization process while changing RE ions and sheds light on the nature of the weak ferromagnetism coexisting with predominated antiferromagnetism. The available large RECrO3 single crystals build a platform for further studies of orthochromates.

10.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(3): 215-218, 2019 May 28.
Artigo em Chinês | MEDLINE | ID: mdl-31257801

RESUMO

OBJECTIVE: To explore aerobic power and energy expenditure of high level rugby players in China, which provide experimental basis for accurate training and nutritional strategy in match-play. METHODS: Eighteen master rugby players were selected as research subjects. The parameters such as VO2max, lactic aicd threshold (LT) and modify conconi test were measured respectively. The differences of energy were compared between the forward and the defender. The data were analyzed by independent sample t test. RESULTS: The VO2max(42.05±3.69 ml/min ·kg-1) of rugby players was poorer. The VO2max of the forward was 38.83±3.52 (ml/min ·kg-1), and that of the defender was 47.31±3.17 (ml/min ·kg-1),and there was significant difference between the forwards and the defenders (P<0.05). The LT of the defenders was obviously higher than that of the forwards. Modifier conconi test had a high correlation (r = 0.772) with VO2max. The average energy consumption in the first half of the game was about(276.94±18.08)kcals, the second half was(225.58±22.86)kcals, and the second half was less than the first half (P<0.05). CONCLUSION: The aerobic power is different between the forwards and the defenders. The power of aerobic of Chinese players is weaker than that of the foreign rugby players.


Assuntos
Metabolismo Energético , Futebol Americano/fisiologia , Povo Asiático , Atletas , China , Humanos , Consumo de Oxigênio
11.
J Mol Graph Model ; 80: 293-298, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29414048

RESUMO

The transition metal and nitrogen co-doped graphene as efficient electrocatalysts of oxygen reduction reaction (ORR) is promising to achieve large-scale applications of the full cells. In this work, we investigated the active sites and ORR mechanism on IrN4 doped divacancy graphene (IrN4-Gra) by using the density functional method. The active sites are identified as the IrN4 moiety and its adjacent ten C atoms. ORR on IrN4-Gra is a four-electron process. OOH hydrogenated into OH + OH is the kinetically most favorable pathway. The rate-determining step is OOH + H → OH + OH with energy barrier 1.01 eV. The predicted working potential is 0.41 V. Hence, IrN4-Gra might be a promising ORR catalyst.


Assuntos
Grafite/química , Metais/química , Modelos Teóricos , Nitrogênio/química , Oxirredução , Oxigênio/química , Adsorção , Catálise , Domínio Catalítico , Teoria da Densidade Funcional , Modelos Moleculares
12.
Zhongguo Zhong Yao Za Zhi ; 36(11): 1427-30, 2011 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22779170

RESUMO

OBJECTIVE: Using Apocynum venetum as a model drug to prepare pulsed-release tablets based on diffusion, swelling, osmotic pressure mechanism and to evaluate the release characteristics. METHOD: The pulsatile release tablets were prepared by film coating methods using HPMC E5 and Eudragit The effect of formulation on pulsatile release of A. venetum was investigated. RESULT: The pulsed-release tablet was prepared by a swelling layer coating which contains HPMC E5 and a controlled-release membrane containning Eudragit. The delayed release time of the tablets was (5.0 +/- 0.5) h. CONCLUSION: The pulsatile release characteristics of A. venetum pulsatile release tablets were confirmed in vitro.


Assuntos
Apocynum/química , Composição de Medicamentos/métodos , Comprimidos/química , Preparações de Ação Retardada/química , Difusão , Medicamentos de Ervas Chinesas/química , Técnicas In Vitro , Lactose/análogos & derivados , Lactose/análise , Metilcelulose/análogos & derivados , Metilcelulose/análise , Pressão Osmótica , Folhas de Planta/química , Ácidos Polimetacrílicos/análise , Solubilidade , Fatores de Tempo
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