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1.
J Colloid Interface Sci ; 650(Pt A): 132-142, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37399749

RESUMO

Converting CO2 into valuable chemicals and fuels through clean and renewable energy electricity provides a way to achieve sustainable development for human societies. In this study, carbon coated nickel catalysts (Ni@NCT) were prepared by solvothermal and high-temperature pyrolysis methods. A series of Ni@NC-X catalysts were obtained by pickling with different kinds of acids for electrochemical CO2 reduction reaction (ECRR). The results show that Ni@NC-N treated with nitric acid has the highest selectivity but lower activity, Ni@NC-S treated with sulfuric acid has the lowest selectivity, and Ni@NC-Cl treated with hydrochloric acid shows the best activity and good selectivity. At -1.16 V, Ni@NC-Cl has a considerable CO yield of 472.9 µmol h-1 cm-2, which is significantly superior to Ni@NC-N (327.5), Ni@NC-S (295.6) and Ni@NC (270.8). The controlled experiments show that there is a synergistic effect between Ni and N. The chlorine adsorbed on the surface can promote the performance of ECRR. The poisoning experiments indicate that the contribution of surface Ni atoms to the ECRR is very small, and the increase of activity is mainly due to the nitrogen doped carbon coated Ni particles. The relationship between activity and selectivity of ECRR on different acid-washed catalysts was correlated by theoretical calculations for the first time, which is also in good agreement with the experimental results.

2.
Chem Biodivers ; 20(6): e202300477, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37212458

RESUMO

Five eremophilane sesquiterpenes including three new ones, named paraconions A-C (1-3), were isolated from an endophytic fungus, Paraconiothyrium sp. from Artemisia selengensis. The structures of these new compounds were established based on spectroscopic methods, including nuclear magnetic resonance (NMR), ultraviolet (UV), and infrared (IR) spectroscopy, as well as high resolution electrospray ionization mass spectrometry (HR-ESI-MS). An anti-inflammatory assay indicated that paraconion B (2) inhibited lipopolysaccharide-induced nitric oxide (NO) production in RAW 264.7 cells, with an IC50 value of 51.7 µM. The compounds discovered in this study will enrich the structural types of secondary metabolites of the endophytic fungus Paraconiothyrium sp.


Assuntos
Ascomicetos , Sesquiterpenos , Animais , Camundongos , Ascomicetos/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/metabolismo , Espectroscopia de Ressonância Magnética , Células RAW 264.7 , Sesquiterpenos/química , Estrutura Molecular
3.
Comput Math Methods Med ; 2022: 5876132, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35082913

RESUMO

The objective of this study was to explore the application value of digital subtraction angiography (DSA) images optimized by deep learning algorithms in vascular restenosis patients undergoing cardiovascular intervention and their nursing efficacy. In this study, a network model for removing artifacts was constructed based on a deep algorithm. 60 patients with coronary artery restenosis were selected as the research objects, and they were randomly divided into the CTA group guided by CT angiography (CTA) and digital subtraction angiography (DSA) group, with 30 cases in each group. The antiartifact network model constructed based on the depth algorithm was applied to the images of CTA and DSA for experiments. After cardiovascular intervention and clinical pathway nursing intervention, it was found that the diameter stenosis rate in the DSA group decreased from 65.82 ± 12.9% to 4.7 ± 1.3%, and the area stenosis rate decreased from 88.4 ± 14.3% to 5.4 ± 1.7%. During the follow-up period of 3-24 months, 3 out of 46 lesions in the DSA group showed restenosis, so the restenosis rate was 6.5%, which was significantly lower than the 18.4% in the CTA group (P < 0.05). In the DSA group, there was 1 case of bleeding, 0 case of hematoma, 2 cases of urinary retention, and 0 case of hypotension, so the total incidence of adverse reactions was 10%, which was significantly lower than the 30% of the CTA group (P < 0.05). The high-sensitivity C-reactive protein (hs-CRP) levels of the two groups of patients were 3.58 ± 2.02 mg/L and 4.36 ± 3.11 mg/L before surgery and 3.49 ± 2.18 mg/L and 4.57 ± 3.4 mg/L after the surgery. The postoperative hs-CRP level in the CTA group was slightly lower than that before the surgery and the postoperative hs-CRP level in the DSA group was slightly higher than that before the surgery, but they were not statistically significant (P > 0.05). The hs-CRP level of the DSA group before and after the surgery was slightly higher than that of the CTA group, but there was no significant difference (P > 0.05). In summary, the network model based on the deep learning algorithm can remove the artifacts in DSA images and present high-quality clear images, and convolutional neural network (CNN) algorithms had a strong ability to automatically learn features in the field of medical image processing and were worthy of being widely used and popularized. In addition, the DSA-guided intervention can reduce the rate of vascular stenosis in patients, showing low probability of postoperative restenosis and adverse reactions and a good clinical effect.


Assuntos
Algoritmos , Angiografia Digital/estatística & dados numéricos , Reestenose Coronária/diagnóstico por imagem , Aprendizado Profundo , Adulto , Idoso , Artefatos , Proteína C-Reativa/metabolismo , Biologia Computacional , Angiografia por Tomografia Computadorizada/estatística & dados numéricos , Reestenose Coronária/enfermagem , Reestenose Coronária/terapia , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/enfermagem , Estenose Coronária/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea
4.
Nat Prod Res ; 35(4): 702-706, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30942104

RESUMO

The antioxidant effect of 95% ethanol extract and its three subfractions, PE (petroleum ether), EtOAc (ethyl acetate), and water extracts, from Gannanzao navel orange peel, were evaluated by ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)), DPPH (1,1-diphenyl-2-picryl-hydrazyl) and FRAP (ferric reducing/antioxidant potential) methods for the first time. Furthermore, the TPC (total polyphenol content), TFC (total flavonoid content), and primary individual flavonoids of the four extracts were analyzed and compared. The results indicated that: (1) the EtOAc extract exhibited the best antioxidant potential among these four extracts in all three antioxidant bioassay platforms; (2) Corresponding to the antioxidant potential, the EtOAc extract contained the highest contents of both TPC and TFC; (3) Compared with other extracts, the EtOAc extract was significantly (p < 0.01) rich in the contents of narirutin, sinensetin, nobiletin, 4',5,6,7-tetramethoxyflavone, and 3,3',4',5,6,7-hexamethoxyflavone, which might be the main bioactive compounds responsible for the excellent antioxidant potential of EtOAc extract.


Assuntos
Antioxidantes/farmacologia , Citrus sinensis/química , Flavonoides/análise , Extratos Vegetais/farmacologia , Benzotiazóis/química , Compostos de Bifenilo/química , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Ferro/metabolismo , Oxirredução , Picratos/química , Extratos Vegetais/química , Polifenóis/análise , Ácidos Sulfônicos/química
5.
Cytotechnology ; 71(2): 475-487, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30874982

RESUMO

Extracts of the cherry blossom plant have been reported to exert various biological effects on human cells. However, no previous investigations have examined the antioxidant and anti-apoptotic effects of these extracts on ultraviolet B (UVB) radiation-induced skin aging. This study explores the underlying mechanisms of the antioxidant and anti-apoptotic effects of cherry blossom extract (CBE) in human keratinocyte (HaCaT) cells. HaCaT cells were treated with CBE at concentrations of 0.5, 1.0, and 2.0% for 24 h and then irradiated with UVB (40 mJ/cm2). CBE effectively and dose-dependently decreased the levels of reactive oxygen species and malondialdehyde, while increasing the activities of superoxide dismutase and glutathione peroxidase. Pretreatment with 1 and 2% CBE attenuated UVB-induced DNA damage by reducing the formation of cyclobutane pyrimidine dimers and 8-hydroxy-20-deoxyguanosine. Furthermore, CBE also prevented UVB-induced apoptosis and significantly downregulated B cell lymphoma 2 (Bcl-2)-associated X, cytochrome-c, and caspase-3 expression, while upregulating Bcl-2 expression. Taken together, these results indicate that CBE protects HaCaT cells from UVB-induced oxidative stress and apoptosis and suggest that CBE could be a potent antioxidant against skin aging.

6.
J Cosmet Dermatol ; 17(5): 935-944, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30160008

RESUMO

INTRODUCTION: Neck skin aging is of particular interest to skin scientists and dermatologists because of the increasing demand for neck wrinkle improvement. This study aimed to determine the neck aging features of Chinese women and to investigate the clinical alterations and mechanical, topographical, and biophysical properties of neck skin. METHODS: A total of 450 Chinese women (age range: 16-66 years) were clinically examined and graded by the same dermatologist using standardized photographs. The skin properties were assessed by noninvasive skin measuring devices. RESULTS: The results showed that different neck aging signs, including the horizontal neck fold, neck sagging, hollowing of emaciated neck, platysmal bands, and neck texture, appeared in different ages, and all of them worsened age-dependently since they manifested. The skin elasticity markedly changed before the onset of most of the aging signs and showed a negative correlation with both age and the severity of these signs. Transepidermal water loss (TEWL) was positively correlated with age, whereas hydration and pH were not significantly correlated with age. We also found that wrinkles (SEw) and average roughness (Ra) were significantly correlated with age. SEw, smoothness, the average depth of roughness (Rz), TEWL, and erythema index were significantly and positively correlated with the severity of the horizontal neck fold, neck sagging, hollowing of emaciated neck, and platysmal bands. CONCLUSION: This is the first study to emphasize that age causes diverse changes in Chinese women's neck skin. The changes in skin elasticity may effectively predict neck aging before the onset of most of the neck aging signs.


Assuntos
Pescoço , Envelhecimento da Pele/etnologia , Envelhecimento da Pele/fisiologia , Adolescente , Adulto , Idoso , Água Corporal/metabolismo , China , Estudos de Coortes , Módulo de Elasticidade/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Adulto Jovem
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