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1.
Small ; 20(6): e2304743, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37803930

RESUMO

Converting solar energy into hydrogen energy using conjugated polymers (CP) is a promising solution to the energy crisis. Improving water solubility plays one of the critical factors in enhancing the hydrogen evolution rate (HER) of CP photocatalysts. In this study, a novel concept of incorporating hydrophilic side chains to connect the backbones of CPs to improve their HER is proposed. This concept is realized through the polymerization of carbazole units bridged with octane, ethylene glycol, and penta-(ethylene glycol) to form three new side-chain-braided (SCB) CPs: PCz2S-OCt, PCz2S-EG, and PCz2S-PEG. Verified through transient absorption spectra, the enhanced capability of PCz2S-PEG for ultrafast electron transfer and reduced recombination effects has been demonstrated. Small- and wide-angle X-ray scattering (SAXS/WAXS) analyses reveal that these three SCB-CPs form cross-linking networks with different mass fractal dimensions (f) in aqueous solution. With the lowest f value of 2.64 and improved water/polymer interfaces, PCz2S-PEG demonstrates the best HER, reaching up to 126.9 µmol h-1 in pure water-based photocatalytic solution. Moreover, PCz2S-PEG exhibits comparable performance in seawater-based photocatalytic solution under natural sunlight. In situ SAXS analysis further reveals nucleation-dominated generation of hydrogen nanoclusters with a size of ≈1.5 nm in the HER of PCz2S-PEG under light illumination.

2.
ACS Appl Mater Interfaces ; 15(28): 33819-33828, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37418573

RESUMO

The strategy of acceptor modification is a powerful technique for tuning the emission color of thermally activated delayed fluorescence (TADF) emitters. In this study, we have successfully designed and synthesized three TADF emitters with donor-acceptor (D-A) structures using a 4-(diphenylamino)-2,6-dimethylphenyl (TPAm) donor and various pyridine-3,5-dicarbonitrile (PC) acceptor units. As a result, three compounds named TPAmbPPC, TPAm2NPC, and TPAmCPPC exhibited greenish-yellow to orange-red emissions with high photoluminescent quantum yields (76-100%) in thin films. Remarkably, a greenish-yellow device based on TPAmbPPC and TPAm2NPC showed a high maximum external quantum efficiency (EQEmax) of 39.1 and 39.0%, respectively. Furthermore, benefiting from the suitable steric hindrance between the acceptor and donor, the nondoped organic light-emitting diodes (OLEDs) based on TPAmbPPC demonstrated an exceptional EQEmax of 21.6%, indicating its promising potential as an efficient emitter for the application of OLED applications. Furthermore, orange-red OLED devices based on TPAmCPPC exhibited a high EQEmax of 26.2%, a CE of 50.1 cd A-1, and a PE of 52.4 lm W-1.

3.
Chem Sci ; 13(44): 12996-13005, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36425506

RESUMO

Owing to the high technology maturity of thermally activated delayed fluorescence (TADF) emitter design with a specific molecular shape, extremely high-performance organic light-emitting diodes (OLEDs) have recently been achieved via various doping techniques. Recently, undoped OLEDs have drawn immense attention because of their manufacturing cost reduction and procedure simplification. However, capable materials as host emitters are rare and precious because general fluorophores in high-concentration states suffer from serious aggregation-caused quenching (ACQ) and undergo exciton quenching. In this work, a series of diboron materials, CzDBA, iCzDBA, and tBuCzDBA, is introduced to realize the effect of steric hindrance and the molecular aspect ratio via experimental and theoretical studies. We computed transition electric dipole moment (TEDM) and molecular dynamics (MD) simulations as a proof-of-concept model to investigate the molecular stacking in neat films. It is worth noting that the pure tBuCzDBA film with a high horizontal ratio of 92% is employed to achieve a nondoped OLED with an excellent external quantum efficiency of 26.9%. In addition, we demonstrated the first ultrathin emitting layer (1 nm) TADF device, which exhibited outstanding power efficiency. This molecular design and high-performance devices show the potential of power-saving and economical fabrication for advanced OLEDs.

4.
Adv Mater ; 33(35): e2008032, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34297444

RESUMO

Highly efficient thermally activated delayed fluorescence (TADF) molecules are in urgent demand for solid-state lighting and full-color displays. Here, the design and synthesis of three triarylamine-pyridine-carbonitrile-based TADF compounds, TPAPPC, TPAmPPC, and tTPAmPPC, are shown. They exhibit excellent photoluminescence quantum yields of 79-100% with small ΔEST values, fast reverse intersystem crossing (RISC), and high horizontal dipole ratios (Θ//  = 86-88%) in the thin films leading to the enhancement of device light outcoupling. Consequently, a green organic light-emitting diode (OLED) based on TPAmPPC shows a high average external quantum efficiency of 38.8 ± 0.6%, a current efficiency of 130.1 ± 2.1 cd A-1 , and a power efficiency of 136.3 ± 2.2 lm W-1 . The highest device efficiency of 39.8% appears to be record-breaking among TADF-based OLEDs to date. In addition, the TPAmPPC-based device shows superior operation lifetime and high-temperature resistance. It is worth noting that the TPA-PPC-based materials have excellent optical properties and the potential for making them strong candidates for TADF practical application.

5.
PLoS One ; 9(10): e109464, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25310192

RESUMO

Tacrolimus (TAC) is the backbone of an immunosuppressive drug used in most solid organ transplant recipients. A single nucleotide polymorphism (SNP) at position 6986G>A in CYP3A5 has been notably involved in the pharmacokinetic variability of TAC. It is hypothesized that CYP3A5 genotyping in patients may provide a guideline for TAC therapeutic regimen. To further evaluate the impact of CYP3A5 variants in donors and recipients, ABCB1 and ACE SNPs in recipients on TAC disposition, clinical and laboratory data were retrospectively reviewed from 90 pediatric patients with liver transplantation and their corresponding donors after 1 year of transplantation. The recipients with CYP3A5 *1/*1 or *1/*3 required more time to achieve TAC therapeutic range during the induction phase, and needed more upward dose during the late induction and the maintained phases, with lower C/D ratio, compared with those with CYP3A5 *3/*3. And donor CYP3A5 genotypes were found to impact on TAC trough concentrations after liver transplantation. No association between ABCB1 or ACE genotypes and TAC disposition post-transplantation was found. These results strongly suggest that CYP3A5 genotyping both in recipient and donor, not ABCB1 or ACE is necessary for establishing a personalized TAC dosage regimen in pediatric liver transplant patients.


Assuntos
Citocromo P-450 CYP3A/genética , Imunossupressores/administração & dosagem , Transplante de Fígado , Polimorfismo de Nucleotídeo Único , Tacrolimo/administração & dosagem , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Adulto , Criança , Pré-Escolar , Feminino , Genótipo , Técnicas de Genotipagem , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Peptidil Dipeptidase A/genética , Tacrolimo/metabolismo , Doadores de Tecidos , Transplantados , Adulto Jovem
6.
Hum Immunol ; 75(3): 203-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24374045

RESUMO

BACKGROUND: Deep venous thrombosis (DVT) and inflammation are two closely related entities. The objective of this study was to evaluate a possible association between interleukin-10 (IL-10) -1082A/G, -819C/T and -592C/A polymorphisms with DVT. METHODS: A case-control study was carried out in 660 patients with DVT and 660 age- and gender-matched healthy controls. Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) assay was applied to identify the polymorphisms mentioned. RESULTS: Patients with DVT had a significantly lower frequency of IL-10 -1082GG genotype [odds ratio (OR)=0.59, 95% confidence interval (CI)=0.39, 0.89; P=0.01] than healthy controls. When stratifying by family history of DVT, it was found that patients with positive family history of DVT had a significantly lower frequency of IL-10 -1082GG genotype (OR=0.13, 95% CI=0.02, 0.95; P=0.04). When stratifying by smoking status, presence of varicose veins, type 2 diabetes mellitus and any hormone administration before, no significant differences were found in any groups. CONCLUSIONS: This study provides evidence that IL-10 -1082A/G polymorphism associated with risk of DVT. However, no association of the IL-10 -592C/A or -819C/T polymorphism with DVT risk was found. Additional well-designed large studies were required for the validation of our results.


Assuntos
Interleucina-10/genética , Trombose Venosa/imunologia , Adulto , Estudos de Casos e Controles , China , Análise Mutacional de DNA , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Risco , Trombose Venosa/genética
7.
Plasmid ; 69(3): 195-201, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22935743

RESUMO

Endothelial progenitor cells (EPCs) play a key role in restoring endothelial function and enhancing angiogenesis. Platelet-derived growth factor C (PDGF-C) is a newly discovered member of the PDGF family that binds to the PDGFR-α homodimer and the PDGFR-α/ß heterodimer. Currently, the biological effects of PDGF-C on EPCs proliferation, migration and adhesion are not well understood. In this study, the full-length coding sequence (CDS) region for the PDGF-C gene was obtained by reverse transcriptase-polymerase chain reaction (RT-PCR). The amplified PDGF-C product was digested and inserted into the pMD 19-T simple vector and then subcloned into a pIRES2-EGFP plasmid to construct the pIRES2-EGFP-PDGF-C eukaryotic expression vector. After it was transfected to EPCs, the expression of PDGF-C protein in EPCs was verified by Western blotting analysis. Finally, we investigated the effects of PDGF-C protein overexpression on EPCs proliferation, migration and adhesion. In conclusion, we constructed a recombinant eukaryotic expression vector containing the complete CDS region of PDGF-C and expressed the full-length and functional PDGF-C protein successfully. Furthermore, PDGF-C promoted EPCs proliferation, migration and adhesion. This offers promise for the development of new therapeutic strategies for improving neovascularization and repair of blood vessel endothelium in patients with ischemic heart disease or peripheral arterial occlusive disease.


Assuntos
Movimento Celular , Proliferação de Células , Células Endoteliais/metabolismo , Linfocinas/metabolismo , Plasmídeos/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Células-Tronco/citologia , Animais , Adesão Celular , Forma Celular , Células Cultivadas , Clonagem Molecular , Células Endoteliais/citologia , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Linfocinas/genética , Masculino , Plasmídeos/genética , Fator de Crescimento Derivado de Plaquetas/genética , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Células-Tronco/metabolismo , Transfecção
8.
J Vasc Surg ; 47(5): 1058-65, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18358673

RESUMO

BACKGROUND: Bone marrow-derived cells are recruited into the thrombus during resolution. This study explored whether mobilization of bone marrow cells with recombinant human granulocyte colony-stimulating factor (rhG-CSF) could enhance the resolution of venous thrombi and the accumulation of macrophages in thrombi and explored the effect of rhG-CSF on cysteine-cysteine chemokine receptor 2 (CCR2) expression. METHODS: The Sprague-Dawley adult rats were randomly divided into four groups: control, sham-operated, thrombus, and treatment groups. Thrombi were induced in the thrombus and treatment group, which received a subcutaneous injection of rhG-CSF once daily for 6 days postoperatively. The thrombus, sham-operated, and control groups received equal volumes of 0.9% saline. The mononuclear cells in peripheral blood were analyzed by an automated hematology analyzer and counted under microscope. The cell marker CD68 was used to determine the number of macrophages in thrombi tissue sections. Levels of monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1alpha (MIP1alpha) in the peripheral blood were detected by enzyme-linked immunosorbent assay. Real-time reverse transcriptase-polymerase chain reaction and Western blot were used to analyze, respectively, the expression of CCR2 messenger RNA in the peripheral blood and CCR2 protein of THP-1 monocyte. RESULTS: At postoperative days 3 (P < .05) and 7 (P < .01), mononuclear cells significantly increased in treatment group (2.1 +/- 0.3, 4.4 +/- 0.3 x 10(6)/L) vs the thrombus group (1.7 +/- 0.2, 1.3 +/- 0.4 x 10(6)/L). The organization and recanalization of thrombi in treatment group progressed more quickly compared with the thrombus group (P < .01). The macrophage number of the thrombus in the treatment group (338 +/- 26 cells/15 high-power fields) increased significantly vs the thrombus group (125 +/- 11 cells/15 high-power fields, P < .01). No statistical difference was observed between the thrombus and treatment group in the MCP-1 and MIP-1alpha level in peripheral blood. Expressions of the CCR2 gene in the peripheral blood of the treatment group significantly increased compared with the thrombus group (P < .05). Recombinant human G-CSF induced higher expression of CCR2 protein of human monocytic cell line THP-1. CONCLUSIONS: Bone marrow mobilization enhanced the resolution and recanalization of venous thrombi. This process was associated with increased macrophage accumulation in thrombi, which might be the result of higher CCR2 expression of monocytes. CLINICAL RELEVANCE: The classic treatment of venous thrombi is anticoagulation. Anticoagulant therapy and thrombolysis both have limited effects on existing thrombi and have a small but significant risk of severe hemorrhage. In clinical practice, we lack specific treatment for patients with venous thrombosis combined with brain hemorrhage or a gastrointestinal activated ulcer, which are contraindicated for anticoagulation and thrombolytic therapy. Enhancing the resolution of venous thrombi would contribute to its therapy. Bone marrow-derived cells are recruited into the thrombus during resolution. Many of these cells express a macrophage phenotype and may represent a population of plastic stem cells that orchestrate thrombus recanalization. Recombinant human granulocyte colony stimulating factor (rhG-CSF) can mobilize monocytic lineage cells into peripheral blood and may contribute to this cell in the thrombi. If rhG-CSF enhances the resolution of venous thrombi and recanalization, it might be used to treat patients with venous thrombi, especially those who have contraindication for anticoagulation and thrombolytic therapy.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Mobilização de Células-Tronco Hematopoéticas/métodos , Células-Tronco/efeitos dos fármacos , Trombose Venosa/tratamento farmacológico , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Células da Medula Óssea/imunologia , Células da Medula Óssea/patologia , Linhagem Celular , Quimiocina CCL2/sangue , Quimiocina CCL3/sangue , Modelos Animais de Doenças , Humanos , Injeções Subcutâneas , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Monócitos/efeitos dos fármacos , Monócitos/imunologia , RNA Mensageiro/sangue , Ratos , Ratos Sprague-Dawley , Receptores CCR2/sangue , Receptores CCR2/genética , Receptores CCR2/metabolismo , Proteínas Recombinantes , Células-Tronco/imunologia , Fatores de Tempo , Veias Cavas/efeitos dos fármacos , Veias Cavas/imunologia , Trombose Venosa/patologia
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