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1.
J Org Chem ; 88(10): 6304-6312, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-36001795

RESUMO

Recently, water promotion effects in the selective oxidation of benzyl alcohol to benzaldehyde have been experimentally recognized and identified. However, the effects of water on the photocatalytic selective oxidation of toluene into benzaldehyde remain elusive. In this work, the Ti3O9H6 clusters in different solvents (water and toluene solvent) are used to study the water-induced effects in photocatalytic oxidation reactions in kinetics and thermodynamics using density functional theory (DFT) calculations. In addition, the influences of the OH groups on catalysts (Ti-OH bonds) from photocatalytic water splitting are also considered. The results clearly demonstrate the water-induced double-edged sword effects in the photocatalytic selective oxidation of toluene. We expect that our work can not only shed light on the mechanisms of photocatalytic selective oxidation of toluene into benzaldehyde and other activation reactions of sp3 C-H bonds but also design and modulate highly efficient photocatalysts.

2.
Phys Chem Chem Phys ; 23(41): 23703-23710, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34642715

RESUMO

The three-dimensional (3D) organic-inorganic halide perovskite MAPbI3 has excellent light-harvesting properties but is unstable. However, the newly synthesized two-dimensional (2D) all-inorganic Ruddlesden-Popper (RP) perovskite Cs2PbI2Cl2 has superior stability but adverse photoelectric properties. Therefore, constructing a 2D Cs2PbI2Cl2/3D MAPbI3 heterostructure is expected to combine the superstability of the 2D material and the high efficiency of the 3D one. The photoelectric properties and charge transfer of 2D Cs2PbI2Cl2/3D MAPbI3 heterostructures are investigated using density functional theory, where MAPbI3 has two kinds of contacting interfaces, i.e., MAI and PbI interfaces. The band gaps of 2D/MAI and 2D/PbI heterostructures are 1.52 eV and 1.40 eV, smaller than those of the free-standing materials (2D ∼ 2.50 eV, MAI ∼ 1.77 eV, and PbI ∼ 1.73 eV), which can broaden the light absorption spectrum. Moreover, the 2D/3D heterostructures are typical type-II heterostructures, which is beneficial to facilitate the separation of carriers for increasing the photoelectric conversion. Interestingly, due to the work function difference (2D ∼ 4.97 eV, MAI ∼ 3.57 eV, and PbI ∼ 5.49 eV), the charge transfer directions of the 2D/MAI and 2D/PbI heterostructures are completely opposite, which shows that interface engineering to impose a consistent interface termination is needed to obtain good performance for solar cells. These results demonstrate that constructing 2D Cs2PbI2Cl2 and 3D MAPbI3 heterostructures by interfacial engineering is a potential strategy to improve the performance of perovskite solar cells (PSCs).

3.
Chin J Nat Med ; 17(9): 641-649, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31526499

RESUMO

Bupleurum polysaccharides (BPs) is isolated from Bupleurum smithii var. parvifolium, a key traditional Chinese medicine. The study was to investigate the effects of BPs on diabetic kidney injury. After two intraperitoneal injections of streptozotozin (STZ) 100 mg·kg-1, renal injury in diabetic mice was induced and BPs was orally administrated at dosages of 30 and 60 mg·kg-1·d-1. The STZ injected mice developed renal function damage, renal inflammation and fibrosis known as diabetic kidney disease (DKD). BPs significantly reduced serum creatinine level and urinary albumin excretion rate, with the attenuated swelling of kidneys. BPs treatment obviously alleviated the pathological damage of renal tissue. The progression of renal injury in BPs treated mice was inhibited with less expression of type IV collagen (Col IV), fibronectin (FN) and α-smooth muscle actin (α-SMA). The inhibition of inflammation in kidney was associated with the reduced level of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). BPs administration suppressed the over-expression of toll like receptor 4 (TLR4) and high-mobility group box 1 (HMGB1) with lowered activity of nuclear factor kappa B (NF-κB) in renal tissue of diabetic mice. Oral administration of BPs effectively prevented the development ofrenal injury in diabetic mice. This study suggested that the protection provided by BPs might affect through the interruption of HMGB1-TLR4 pathway, leading to the inhibition of renal inflammation and fibrotic process.


Assuntos
Bupleurum/química , Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Proteína HMGB1/metabolismo , Polissacarídeos/uso terapêutico , Receptor 4 Toll-Like/metabolismo , Animais , Citocinas/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Nefropatias Diabéticas/induzido quimicamente , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Inflamação/metabolismo , Inflamação/prevenção & controle , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Masculino , Camundongos Endogâmicos C57BL , Raízes de Plantas/química , Polissacarídeos/administração & dosagem , Polissacarídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Estreptozocina/toxicidade , Fator de Transcrição RelA/metabolismo
4.
Drug Des Devel Ther ; 12: 1941-1951, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29983548

RESUMO

PURPOSE: Yanghe Pingchuan granules (YPG), a hospital preparation developed by The First Affiliated Hospital, Anhui University of Chinese Medicine, has been used for the clinical treatment of bronchial asthma (BA) for several decades. This study aimed to explore the mechanism of action of YPG in the treatment of BA. MATERIALS AND METHODS: Male Sprague Dawley rats (n=60) were randomly divided into six groups (n=10 per group): control, a BA model, positive drug control (Guilong Kechuanning capsules; a proven effective treatment for BA), and model rats treated with a high, medium, or low dose of YPG. H&E staining was used to detect pathological changes in the bronchial tubes. The mRNA expression levels of PI3K, PKB, PCNA, and AR were determined by real-time PCR, and the protein levels of phospho- (p-)PI3K, p-PKB, p-PCNA, and p-AR were detected by Western blotting. ELISAs were used to detect the expression of PIP2, PIP3 IL-6, IL-8, IL-1ß, and epinephrine (EPI). RESULTS: H&E staining demonstrated that BA can be ameliorated using YPG. Real-time PCR, Western blotting, and ELISA indicated that use of YPG decreased expression of the phosphoinositide 3-kinase (PI3K) signaling pathway and PCNA, and can also ameliorate the condition kidney Yang deficiency, which is associated with BA in Chinese traditional medicine. CONCLUSION: YPG can attenuate BA therapeutically in a dose-dependent manner. The mechanism underlying its therapeutic effect comprises influences on three features that contribute to BA: the PI3K signaling pathway, cell proliferation, and "kidney-Yang deficiency".


Assuntos
Remodelação das Vias Aéreas/efeitos dos fármacos , Asma/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Chinesa , Animais , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/uso terapêutico , Masculino , Fosfatidilinositol 3-Quinases/fisiologia , Antígeno Nuclear de Célula em Proliferação/análise , Proteínas Proto-Oncogênicas c-akt/fisiologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
5.
J Ethnopharmacol ; 173: 81-90, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26190353

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Houttuynia cordata (HC) has been used as a folk therapy to treat pulmonary infections. This study aimed to determine the role and mechanism of action of polysaccharides isolated from HC (HCP) in lipopolysaccharide (LPS)-induced ALI in the mice. MATERIALS AND METHODS: LPS was delivered by the intratracheal route to Balb/c mice 2h before HCP (40, 80 and 160mg/kg) administration. RESULTS: The number of total cells, protein and tumor necrosis factor-α (TNF-α) concentrations in bronchoalveolar lavage fluid, the wet/dry weight ratio (w/d) of lungs and pulmonary pathology of each mouse were analyzed, it was found that HCP significantly alleviated ALI induced by LPS. Moreover, in lungs of mice, it was found that the infiltration of inflammatory cells, the expression of Toll-like receptor 4 and complement deposition were significantly decreased by HCP treatment. In vitro assays showed that C5a, a complement activation product, induced significant macrophage migration and treatment with HCP prevented it. The in vitro results also proved that LPS increased nitric oxide and pro-inflammatory cytokines (TNF-α, interleukin-6, and interleukin-1ß) production, and HCP antagonized these effects of LPS. It was also found that HCP alone augmented secretion of some pro-inflammatory cytokines. CONCLUSION: These results indicate that HCP may alleviate LPS induced lung inflammatory injury, which may be associated with its inhibitory effect on the over activation of complement and macrophages. This suggests a potential role to treat ALI.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Houttuynia , Polissacarídeos/uso terapêutico , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/imunologia , Lesão Pulmonar Aguda/patologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Contagem de Células , Quimiotaxia , Proteínas do Sistema Complemento/imunologia , Citocinas/imunologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/patologia , Macrófagos/fisiologia , Masculino , Camundongos Endogâmicos BALB C , Fitoterapia , Polissacarídeos/farmacologia , Receptor 4 Toll-Like/imunologia
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