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1.
ACS Appl Mater Interfaces ; 14(40): 45734-45741, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36166320

RESUMO

An efficient artificial light-harvesting system with a two-step sequential energy transfer was fabricated in the aqueous solution based on the host-guest interactions between cyano-substituted p-phenylenevinylene derivative (PPTA) and a water-soluble pillar[5]arene (WP5). PPTA-WP5 complex could self-assemble into nanoparticles, and two fluorescent dyes eosin Y (EY) and Nile Red (NIR) are employed as acceptors to realize sequential energy transfer. The PPTA-WP5-EY-NIR system could achieve efficient two-step sequential energy transfer process from PPTA-WP5 to EY and then to NIR (67% for the first step and 66% for the second step). Moreover, to make full use of the harvested energy, the hydrophobic microenvironment in the assembled nanoparticles is used to promote the aerobic cross-dehydrogenative coupling (CDC) reaction in aqueous medium with 88% yield after 12 h of irradiation. To our knowledge, this is the first example of artificial LHS with two-step energy transfer used to catalyze the CDC reaction in aqueous medium. This work directly mimics the function of photosynthesis in nature of converting solar energy into chemical energy in aqueous solution.

2.
Soft Matter ; 17(43): 9871-9875, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34724526

RESUMO

An artificial light-harvesting system with two-step sequential energy transfer was constructed in aqueous media based on cyano-substituted p-phenylenevinylene derivative (PPTA) and bis-(p-sulfonatocalix[4]arenes) (BSC4) supramolecular polymers formed through host-guest interactions, in which two different fluorescent dyes, eosin Y (EY) and sulforhodamine (SR101), were employed as energy acceptors. The obtained artificial light-harvesting system can achieve an efficient two-step energy transfer process from PPTA-BSC4 to EY and then to SR101 with high energy-transfer efficiencies of up to 36.6% and 40.8%, respectively. More importantly, the harvested energy from the PPTA-BSC4 + EY + SR101 system can be used to promote the dehalogenation of α-bromoacetophenone with a yield of 89% in aqueous solution.

3.
Cancer Manag Res ; 12: 7087-7095, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32848463

RESUMO

PURPOSE: To investigate the specific effect and underlying mechanism of microRNA-26a-5p (miR-26a) in cutaneous squamous cell carcinoma (CSCC). METHODS: miR-26a and MMP14/16 mRNA expression were detected by qRT-PCR analysis. Functional experiments were used to detect the role of miR-26a on CSCC progression. Western blot was used for protein detection. Luciferase assay was used to detect miR-26a directly targeting MMP14 and MMP16. Xenograft nude mice model was used to determine the effect of miR-26a on tumorigenesis. RESULTS: miR-26a was decreased in CSCC tissues and cells. Forced miR-26a suppressed the progression of SCL-1 and A431 cells. Furthermore, miR-26a directly targeted MMP14 and MMP16 to inhibit their expression. Forced expression of MMP14 and MMP16 removed the miR-26a's inhibitory effect on CSCC development. The in vivo tumor growth assay showed that miR-26a suppressed CSCC tumorigenesis by targeting MMP14 and MMP16. CONCLUSION: Our study suggested miR-26a inhibits cancer cell proliferation, migration and invasion in CSCC by targeting MMP14 and MMP16.

4.
J Surg Res ; 245: 467-474, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31446188

RESUMO

BACKGROUND: This study aims to investigate the effect of hydrogen sulfide on the mitogen-activated protein kinases signaling pathway in in vitro cultured skin macrophages of burned rats. MATERIALS AND METHODS: Thirteen healthy Sprague-Dawley rats were divided into five groups: normal control group, burned control group, sodium hydrogen sulfide group, glibenclamide group, and sodium hydrogen sulfide + glibenclamide group. The burned rats were made into a deep II° 5% total body surface area flame burn injury model. The skin basement macrophages were separated from the skin of normal rats and the wound skin of burned rats and cultured. At 1, 6, and 12 h after intervention, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 protein levels were detected by Western blot, and ERK, p38, and JNK messenger RNA (mRNA) levels were detected by reverse transcription polymerase chain reaction. RESULTS: Differences in ERK, p38, and JNK mRNA and protein levels between the normal control group and burned control group were statistically significant (P < 0.05). At the same time point, the ERK, p38, and JNK mRNA and protein levels in the NaSH group were different from those in other groups, and the differences were statistically significant (P < 0.05). CONCLUSIONS: Hydrogen sulfide has a regulatory effect on ERK, JNK, and p38 in the mitogen-activated protein kinases signaling pathway in macrophages of burned rats.


Assuntos
Queimaduras/tratamento farmacológico , Sulfeto de Hidrogênio/uso terapêutico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Animais , Queimaduras/imunologia , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Sulfeto de Hidrogênio/farmacologia , Masculino , Ratos Sprague-Dawley
5.
J Photochem Photobiol B ; 197: 111515, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31255939

RESUMO

An extraordinary arrangement of research is as yet going on in the area of orthopedic implants advancement to determine different issues being looked by the engineering today. In spite of a few detriments of the orthopedic metallic inserts, they keep on being utilized, essentially as a result of their unrivaled mechanical properties. We investigated the conceivable utilization of silicon carbide (SiC) as a nano-ceramic covering material of titanium (Ti)-based all out femoral substitution implants. The thought is to keep wear garbage arrangement from the delicate titanium exterior. Silicon carbide is a hard and firmly holding bio-ceramic surface substance, and in light of these physico-chemical properties, it isn't actually degradable, just like the case with apatite (HA). To improve cytocompatibility and osseous-integration, we deposited anodized titanium nanotubes (TiO2) inserts, by electrochemical deposition method (EDM), with silicon carbide (SiC) with apatite (SiC@HA). The deposition was affirmed by SEM, while phase composition properties were assessed by XRD. Calcium affidavit, osteocalcin creation, and articulation of bone genes were essentially higher in rodent osteoblast cell culture on SiC@HA-covered anodized titanium nanotubes than in cells cultured on uncoated anodized titanium nanotubes. Implantation into rodent femurs likewise demonstrated that the SiC@HA-covered substance had unrivaled osseous-integration movement in correlation with that of customary inserts, as evaluated by in vivo tomography and histology. Therefore, anodized titanium nanotubes covered with SiC@HA holds guarantee as an orthopedic implant substance.


Assuntos
Regeneração Óssea , Compostos Inorgânicos de Carbono/química , Materiais Revestidos Biocompatíveis/química , Durapatita/química , Nanopartículas/química , Compostos de Silício/química , Titânio/química , Animais , Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Adesão Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/uso terapêutico , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Fraturas do Fêmur/terapia , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteocalcina/metabolismo , Próteses e Implantes , Ratos
6.
Medicine (Baltimore) ; 97(15): e0398, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29642203

RESUMO

BACKGROUND: The terrible triad of the elbow (TTE) is a difficult injury, and the usual TTE consists of posterior dislocation of the elbow, radial head fracture, and coronoid fracture. The target of this retrospective study is to explore the effect, postoperative complications, and prognostic factors in patients with TTE undergoing arthroscopic surgery with three different operative approaches. METHODS: Patients with TTE underwent arthroscopic surgery were treated using lateral, anterior medial, or combined lateral and anterior medial approaches, respectively. In order to analyze the postoperative complications and the effect of arthroscopic surgery for patients with TTE, the function of elbow joint before and after the surgery was evaluated and the flexion-extension of elbow joint and rotation of elbow joint and forearm were measured. RESULTS: The evaluation results obtained from patients underwent 3 different operative approaches revealed that after surgery, patients receiving arthroscopic surgery using combined lateral and anterior medial approach had superior flexion-extension of elbow joint, rotation of elbow joint and forearm, higher Mayo Elbow Performance Score (MEPS) and more cases of Broberg-Morrey grade 0, and lower complication rate, compared with those using lateral or anterior medial approach. A key finding in the study demonstrated that fracture type, operative approach, and postoperative complications were factors related with the effect of arthroscopic surgery for patients with TTE. CONCLUSION: Collectively, the key findings obtained from the present study supported the notion that the effect of arthroscopic surgery in combined lateral and anterior medial approach is much better than in lateral approach or anterior medial approach, and is related with fracture type, operative approach, and postoperative complications.


Assuntos
Artroscopia/efeitos adversos , Artroscopia/métodos , Lesões no Cotovelo , Articulação do Cotovelo/cirurgia , Luxações Articulares/cirurgia , Complicações Pós-Operatórias/etiologia , Fraturas do Rádio/cirurgia , Ulna/lesões , Ulna/cirurgia , Adulto , Articulação do Cotovelo/fisiopatologia , Feminino , Seguimentos , Humanos , Luxações Articulares/classificação , Luxações Articulares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/fisiopatologia , Fraturas do Rádio/classificação , Fraturas do Rádio/fisiopatologia , Amplitude de Movimento Articular/fisiologia , Ulna/fisiopatologia
7.
ChemSusChem ; 11(4): 726-734, 2018 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-29372624

RESUMO

It is of great significance to convert platform molecules and their derivatives into high value-added alcohols, which have multitudinous applications. This study concerns systematic conversion of 2-methyltetrahydrofuran (MTHF), which is obtained from furfural, into 1-pentanol acetate (PA) and 1,4-pentanediol acetate (PDA). Reaction parameters, such as the Lewis acid species, reaction temperature, and hydrogen pressure, were investigated in detail. 1 H NMR spectroscopy and reaction dynamics study were also conducted to help clarify the reaction mechanism. Results suggested that cleavage of the primary alcohol acetate was less facile than that of the secondary alcohol acetate, with the main product being PA. A PA yield of 91.8 % (150 °C, 3 MPa H2 , 30 min) was achieved by using Pd/C and Sc(OTf)3 as a cocatalytic system and an 82 % yield of PDA was achieved (150 °C, 30 min) by using Sc(OTf)3 catalyst. Simultaneously, the efficient conversion of acetic esters into alcohols by simple saponification was carried out and led to a good yield.


Assuntos
Acetatos/síntese química , Álcoois/síntese química , Furanos/química , Catálise , Mesilatos , Paládio , Pentanóis/síntese química , Pressão , Escândio , Temperatura
8.
ChemSusChem ; 9(10): 1209-15, 2016 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-27075722

RESUMO

The highly selective hydrogenation/hydrolytic ring-opening reaction of 5-hydroxymethylfuraldehyde (5-HMF) was catalyzed by homogeneous Cp*Ir(III) half-sandwich complexes to produce 1-hydroxy-2,5-hexanedione (HHD). Adjustment of pH was found to regulate the distribution of products and reaction selectivity, and full conversion of 5-HMF to HHD with 99 % selectivity was achieved at pH 2.5. A mechanistic study revealed that the hydrolysis/ring-opening reaction of 2,5-bis-(hydroxymethyl)furan is the important intermediate reaction step. In addition, an isolated yield of 85 % for HHD was obtained in a 10 g-scale experiment, and the reaction with fructose as the starting material also led to a 98 % GC yield (71.9 % to fructose) of HHD owing to the excellent tolerance of the catalyst under acidic conditions.


Assuntos
Formiatos/química , Furaldeído/análogos & derivados , Irídio/química , Compostos Organometálicos/química , Água/química , Soluções Tampão , Catálise , Furaldeído/química , Hexanonas/química , Concentração de Íons de Hidrogênio , Soluções
9.
ChemSusChem ; 8(24): 4250-5, 2015 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-26611542

RESUMO

Using a metal triflate and Pd/C as catalysts, alkanes were prepared from bioderived furans in a one-pot hydrodeoxygenation (HDO) process. During the reaction, the metal triflate plays a crucial role in the ring-opening HDO of furan compounds. The entire reaction process has goes through two major phases: at low temperatures, saturation of the exocyclic double bond and furan ring are catalyzed by Pd/C; at high temperatures, the HDO of saturated furan compounds is catalyzed by the metal triflate. The reaction mechanism was verified by analyzing the changes of the intermediates during the reaction. In addition, different metal triflates, solvents, and catalyst recycling were also investigated.


Assuntos
Alcanos/química , Biomassa , Éteres Cíclicos/química , Furanos/química , Mesilatos/química , Paládio/química , Catálise , Hidrogênio/química , Cinética , Oxigênio/química , Pressão , Temperatura
10.
J Org Chem ; 79(15): 7220-5, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25033394

RESUMO

A 2,2-azobis(isobutyronitrile) (AIBN) catalyzed oxidative cleavage of gem-disubstituted alkenes with molecular oxygen as the oxidant has been described. Carbonyl compounds were obtained as the desired products in high yield under mild conditions. Based on previous documents and current experimental results, a relatively reasonable mechanism is proposed.


Assuntos
Alcenos/química , Compostos Azo/química , Nitrilas/química , Oxidantes/química , Oxigênio/química , Catálise , Estrutura Molecular , Estereoisomerismo
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