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1.
Angew Chem Int Ed Engl ; 63(21): e202319755, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38386897

RESUMO

All-polymer solar cells (all-PSCs) have been regarded as one of the most promising candidates for commercial applications owing to their outstanding advantages such as mechanical flexibility, light weight and stable film morphology. However, compared to large amount of new-emerging excellent polymer acceptors, the development of high-performance polymer donor lags behind. Herein, a new D-π-A type polymer donor, namely QQ1, was developed based on dithienoquinoxalineimide (DTQI) as the A unit, benzodithiophene with thiophene-conjugated side chains (BDTT) as the D unit, and alkyl-thiophene as the π-bridge, respectively. QQ1 not only possesses a strong dipole moment, but also shows a wide band gap of 1.80 eV and a deep HOMO energy level of -5.47 eV, even without halogen substituents that are commonly indispensable for high-performance polymer donors. When blended with a classic polymer acceptor PY-IT, the QQ1-based all-PSC delivers an outstanding PCE of 18.81 %. After the introduction of F-BTA3 as the third component, a record PCE of 19.20 % was obtained, the highest value reported so far for all-PSCs. The impressive photovoltaic performance originates from broad absorption range, reduced energy loss, and compact π-π stacking. These results provide new insight in the rational design of novel nonhalogenated polymer donors for further development of all-PSCs.

2.
Angew Chem Int Ed Engl ; 63(11): e202319658, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38265195

RESUMO

Developing low-cost and high-performance n-type polymer semiconductors is essential to accelerate the application of organic thermoelectrics (OTEs). To achieve this objective, it is critical to design strong electron-deficient building blocks with simple structure and easy synthesis, which are essential for the development of n-type polymer semiconductors. Herein, we synthesized two cyano-functionalized highly electron-deficient building blocks, namely 3,6-dibromopyrazine-2-carbonitrile (CNPz) and 3,6-Dibromopyrazine-2,5-dicarbonitrile (DCNPz), which feature simple structures and facile synthesis. CNPz and DCNPz can be obtained via only one-step reaction and three-step reactions from cheap raw materials, respectively. Based on CNPz and DCNPz, two acceptor-acceptor (A-A) polymers, P(DPP-CNPz) and P(DPP-DCNPz) are successfully developed, featuring deep-positioned lowest unoccupied molecular orbital (LUMO) energy levels, which are beneficial to n-type organic thin-film transistors (OTFTs) and OTEs performance. An optimal unipolar electron mobility of 0.85 and 1.85 cm2 V-1 s-1 is obtained for P(DPP-CNPz) and P(DPP-DCNPz), respectively. When doped with N-DMBI, P(DPP-CNPz) and P(DPP-DCNPz) show high n-type electrical conductivities/power factors of 25.3 S cm-1 /41.4 µW m-1 K-2 , and 33.9 S cm-1 /30.4 µW m-1 K-2 , respectively. Hence, the cyano-functionalized pyrazine CNPz and DCNPz represent a new class of structurally simple, low-cost and readily accessible electron-deficient building block for constructing n-type polymer semiconductors.

3.
Polymers (Basel) ; 14(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36080665

RESUMO

The molecular design of a wide-bandgap polymer donor is critical to achieve high-performance organic photovoltaic devices. Herein, a new dibenzo-fused quinoxalineimide (BPQI) is successfully synthesized as an electron-deficient building block to construct donor-acceptor (D-A)-type polymers, namely P(BPQI-BDT) and P(BPQI-BDTT), using benzodithiophene and its derivative, which bears different side chains, as the copolymerization units. These two polymers are used as a donor, and the narrow bandgap (2,20-((2Z,20Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo [3,4-e]thieno[2,″30':4',50]thieno[20,30:4,5]pyrrolo[3,2g]thieno[20,30:4,5]thieno[3,2-b]indole-2,10 diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile) Y6 is used as an acceptor to fabricate bulk heterojunction polymer solar cell devices. Y6, as a non-fullerene receptor (NFA), has excellent electrochemical and optical properties, as well as a high efficiency of over 18%. The device, based on P(BPQI-BDTT):Y6, showed power conversion efficiencies (PCEs) of 6.31% with a JSC of 17.09 mA cm-2, an open-circuit voltage (VOC) of 0.82 V, and an FF of 44.78%. This study demonstrates that dibenzo-fused quinoxalineimide is a promising building block for developing wide-bandgap polymer donors.

4.
J BUON ; 26(3): 1185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34269002

RESUMO

The Editors of JBUON issue an Expression of Concern to 'MicroRNA-22 regulates the proliferation, drug sensitivity and metastasis of human glioma cells by targeting SNAIL1', by Yunqiang Zhang, Lijun Tu, Xiuhong Zhou, Bin Li; JBUON 2020;25(1):491-496; PMID: 32277674. Following the publication of the above article, readers drew to our attention that part of the data was possibly unreliable. We sent emails to the authors with a request to provide the raw data to prove the originality, but received no reply. Therefore, as we continue to work through the issues raised, we advise readers to interpret the information presented in the article with due caution. We thank the readers for bringing this matter to our attention. We apologize for any inconvenience it may cause.


Assuntos
Glioma , MicroRNAs , Preparações Farmacêuticas , Linhagem Celular Tumoral , Proliferação de Células , Humanos
5.
J BUON ; 25(1): 491-496, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32277674

RESUMO

PURPOSE: Gliomas are aggressive brain tumors accounting for significant mortality across the globe. Biomarkers for early detection and therapeutic targets for efficient treatment are lacking for glioma. This study was undertaken to investigate the role and therapeutic implications of miR-22 in glioma. METHODS: U-87 glioma cell line was used in this study. qRT-PCR was employed for expression analysis. MTT assay was used for determination of cell viability. Lipofectamine 2000 was used for transfection. Flow cytometry was used for cell analysis. Wound healing assay and transwell assay were used for monitoring cell migration and invasion. Western blot analysis was used for estimation of protein expression. RESULTS: The miR-22 expression was found decreased in glioma cells. Overexpression of miR-22 resulted in arrest of the U-87 glioma cells at G2/M checkpoint of the cell cycle. The percentage of apoptotic U-87 cells in G2/M phase were 13.05% in negative control (NC) and 29.06% in miR-22 mimics transfected cells. The cell cycle arrest promoted by miR-22 overexpression was also associated with depletion of cyclin B1 expression in U-87 cells. Furthermore, miR-22 could also significantly increase the sensitivity of glioma U-87 cells to cisplatin. The TargetScan analysis and dual luciferase assay showed SNAIL1 to be the target of miR-22. The expression of SNAIL1 was also enhanced in all the glioma cells and miR-22 overexpression could cause suppression of the SNAIL1 expression in U-87 cells. Furthermore, SNAIL1 silencing could also cause decline in the viability of the U-87 cells. The wound healing assay showed that miR-5 overexpression caused decrease in the migration of U-87 cells, while the transwell assay showed decline in the invasion of miR-22 mimics transfected U-87 cells. CONCLUSION: Taken together, miR-22 may exhibit therapeutic implications in glioma and may prove useful in glioma treatment.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , MicroRNAs/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Pontos de Checagem da Fase G2 do Ciclo Celular/fisiologia , Glioma/genética , Glioma/patologia , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/fisiologia , MicroRNAs/genética , Metástase Neoplásica , Fatores de Transcrição da Família Snail/biossíntese , Fatores de Transcrição da Família Snail/genética , Transfecção
6.
Food Funct ; 11(12): 10954-10967, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33283810

RESUMO

Previously, anthocyanins were successfully acylated with lauric acid using Novozym 435 lipase, and the corresponding products were confirmed to have higher stability. As novel synthetic compounds, their toxicological safety has not been evaluated. Therefore, acute, subacute and subchronic toxicities of anthocyanin-lauric acid derivatives (ALDs) were investigated while their antioxidant activities were also evaluated in vitro. The acute toxicity results showed that the 50% lethal dose (LD50) of ALDs in mice was >10 g kg-1. Subsequently, the subacute toxicity test was conducted by oral administration of ALDs at doses of 0.63, 1.25 and 2.50 g kg-1 for 28 days. No adverse effect of ALDs on body weight, food/water intake, organ coefficient and histology was observed. Though there were some fluctuations in AST and ALT, the tested biochemical parameters were maintained within the normal ranges. The subchronic toxicity test results demonstrated that less than 0.60 g of ALDs per kg BW intake did not affect mortality, body weight, food/water intake, gross pathology, histology, hematology and serum biochemistry. Furthermore, cyanidin-3-(6''-dodecanoyl)-glucoside, the main component of ALDs, had a beneficial reducing power and a strong DPPH˙, ABTS+˙, and O2-˙ scavenging activity. This study provides an imperative reference to the safety of ALDs, suggesting their application as novel colorants or antioxidants in food and therapeutics.


Assuntos
Antocianinas/metabolismo , Antocianinas/toxicidade , Antioxidantes/farmacologia , Ácidos Láuricos/metabolismo , Ácidos Láuricos/toxicidade , Acilação , Animais , Antocianinas/química , Peso Corporal , Modelos Animais de Doenças , Ingestão de Alimentos , Enzimas Imobilizadas , Feminino , Proteínas Fúngicas , Glucosídeos , Rim/efeitos dos fármacos , Rim/patologia , Ácidos Láuricos/química , Dose Letal Mediana , Lipase , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Testes de Toxicidade , Testes de Toxicidade Subcrônica
7.
Biology (Basel) ; 9(8)2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32759690

RESUMO

The interest in anthocyanins used in food, cosmetic, and pharmaceutical industries has increased the research in order to improve their stability while maintaining bioactivity. In this work, cyanidin-3-glucoside lauryl ester (Cy3glc-C12) was enzymatically synthesized, using Novozym 435 as a catalyst, as well as to obtain a kinetic model for the bioprocess. Its liposolubility, UV-VIS absorbance property, thermostability, and potential proliferative effect on intestinal probiotics were also studied. The maximum conversion yield (68.7 ± 2.1%) was obtained with a molar ratio (substrate:donor) of 1:56, 435 16.5 g/L Novozym, temperature of 56 °C, and a time of 28 h via the acylation occurred at 6''-OH position of the glucoside. The kinetics of the reaction is consistent with a ping-pong bi-bi mechanism and the parameters of the respective kinetic equations are reported. Compared with native Cy3glc, the liposolubility, pH resistivity and thermostability of Cy3glc-C12 were significantly improved. The growth kinetics of Bifidobacteria and Lactobacillus was established based on the Logistic equation, and Cy3glc-C12 could promote their proliferation especially during the logarithmic growth, in which lower pH and more bacteria population were found compared with those of media without anthocyanins. This research provided a reference for the industrial production of Cy3glc-C12 and extended its application to natural products in lipophilic systems.

8.
Food Chem Toxicol ; 133: 110796, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31472226

RESUMO

Effects of red raspberry extract (RRE) intake on hyperlipidemia mice induced by high-fat diet (HFD) were investigated in this study. After intragastric gavage of RRE for 8 weeks, the body weight and the adipose tissue mass of mice in RRE administration groups significantly (p < 0.05) decreased compared to the group without RRE treatment. RRE treatment significantly (p < 0.05) lowered triglyceride and total cholesterol levels of hyperlipidemia mice. Pparα, Hmgcr, Ldlr, Cyp7a1, Acsl3, Pnpla2 and Pin4 were confirmed as the regulatory genes by transcriptome analysis and qRCR validation. According to KEGG pathway analysis, target genes such as Cyp7a1 and Pin4 were further regulated by the activation of PPARα resulting from RRE supplementation. Meanwhile, liver cholesterol synthesis and conversion were inhibited by the expressions of Hmgcr and Cyp7a1 genes regulated by RRE intake, and Ldlr gene was down-regulated to limit the transport of cholesterol. In addition, RRE treatment could accelerate the conversion from triglyceride to fatty acid. To conclusion, RRE intake would be a protection against diet-induced hypertriglyceridemia.


Assuntos
Hiperlipidemias/dietoterapia , PPAR alfa/metabolismo , Extratos Vegetais/farmacologia , Rubus/química , Transdução de Sinais/efeitos dos fármacos , Animais , Colesterol/metabolismo , Dieta Hiperlipídica , Frutas/química , Expressão Gênica/efeitos dos fármacos , Hidroximetilglutaril-CoA Redutases/metabolismo , Lipólise/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/análise , Triglicerídeos/metabolismo
9.
Med Sci Monit Basic Res ; 24: 216-224, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30531680

RESUMO

BACKGROUND Curcumin has clear anti-tumor activity in various carcinomas. It regulates various signaling pathways like Wnt/ß-catenin and JAK2/STAT3, which play vital roles in cell proliferation of several carcinomas, but to the best of our knowledge, there are currently no published reports on human glioma CHME cells. Therefore, the aim of this study was to explore the effect of curcumin on human glioma CHME cells. MATERIAL AND METHODS The CHME cell line was purchased from American Type Culture Collection (ATCC). The expressions of caspases 3, caspases 9, PARP, BAX, and BCL2 were detected by Western blot. Annexin V FITC, mitochondrial membrane potential, and reactive oxygen species were detected by flow cytometry. DAPI staining was detected by fluorescence microscopy. Cell viability was assessed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay. RESULTS We found that curcumin has cytotoxic activity in human glioma CHME cells, as shown by DAPI staining, annexin V/PI, and nuclear morphology. We found that cell growth decreased with increased concentration of curcumin, as well as sowing effects on expression of caspase-3, caspase-9, and cleavage of PARP, which suggests apoptotic cascade activity. The increase in reactive oxygen species and loss of mitochondrial membrane potential (Δψmt) in concentration-dependent manners suggests biochemical induction of apoptosis in CHME cells. CONCLUSIONS Curcumin has effective anticancer activity in human glioma CHME cells by inducing the apoptotic pathway.


Assuntos
Apoptose/efeitos dos fármacos , Curcumina/farmacologia , Glioma/tratamento farmacológico , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glioma/metabolismo , Glioma/patologia , Humanos , Mitocôndrias/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
10.
PLoS One ; 13(4): e0195754, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29630662

RESUMO

Anthocyanins are naturally active substances. In this study, anthocyanins from black rice were obtained by membrane filtration and column chromatography separation. Five anthocyanin monomers in black rice extract were identified by HPLC-MS/MS, and the major anthocyanin monomer (cyanidin-3-glucoside, C3G) was purified by preparative HPLC (Pre-HPLC). The proliferative effects of the anthocyanins on Bifidobacteria and Lactobacillus were investigated by determining the media pH, bacterial populations and metabolic products. After anaerobic incubation at 37 °C for 48 h, not only the pH of the media containing C3G was lower than that of the extract of black rice anthocyanin (BRAE), but the numbers of both Bifidobacteria and Lactobacillus were also significantly increased. Furthermore, hydroxyphenylpropionic, hydroxyphenylacetic, and hydroxybenzoic acids and other metabolites were detected by GC-MS in vitro. Our results revealed that the anthocyanins and anthocyanin monomers from black rice had prebiotic activity and they were metabolized into several small molecules by Bifidobacteria and Lactobacillus.


Assuntos
Antocianinas/farmacologia , Bifidobacterium/crescimento & desenvolvimento , Lactobacillus/crescimento & desenvolvimento , Metaboloma/efeitos dos fármacos , Oryza/metabolismo , Prebióticos/análise , Antocianinas/isolamento & purificação , Bifidobacterium/efeitos dos fármacos , Técnicas In Vitro , Lactobacillus/efeitos dos fármacos
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