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1.
Angew Chem Int Ed Engl ; 63(29): e202405255, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38682659

RESUMO

Precise regulation of the active site structure is an important means to enhance the activity and selectivity of catalysts in CO2 electroreduction. Here, we creatively introduce anionic groups, which can not only stabilize metal sites with strong coordination ability but also have rich interactions with protons at active sites to modify the electronic structure and proton transfer process of catalysts. This strategy helps to convert CO2 into fuel chemicals at low overpotentials. As a typical example, a composite catalyst, CuO/Cu-NSO4/CN, with highly dispersed Cu(II)-SO4 sites has been reported, in which CO2 electroreduction to formate occurs at a low overpotential with a high Faradaic efficiency (-0.5 V vs. RHE, FEformate=87.4 %). Pure HCOOH is produced with an energy conversion efficiency of 44.3 % at a cell voltage of 2.8 V. Theoretical modeling demonstrates that sulfate promotes CO2 transformation into a carboxyl intermediate followed by HCOOH generation, whose mechanism is significantly different from that of the traditional process via a formate intermediate for HCOOH production.

2.
Arch Toxicol ; 93(10): 2993-3003, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506784

RESUMO

As one of the isoprenoids and widely derived from many fruits and vegetables, ß-ionone (BI) has a potent inhibitory proliferation of cancer cells in vitro and in vivo. However, its exact mechanism is still uncompleted understood and needs to be further verified. Cyclooxygenase-2 (COX-2), as a potential target of cancer chemoprevention, has been played pivotal roles in proliferation of tumor cells and carcinogenesis. Thus, the objective of present study was to determine that BI inhibited the activity of COX-2 in breast cancer and related to cancer cell models. Cell proliferation, DNA synthesis, the distribution of cell cycle, apoptosis induction and the expression of P38-MAPK protein were determined in MCF-7 cells by methylene blue, 3H-thymidine (TdR) incorporation, flow cytometry, TUNEL and Western blotting assays. Quinone reductase (QR) activity was determined in murine hepatoma Hepa1c1c7 cells by enzyme-linked immunosorbent assay (ELISA). The expression of COX-2 in a phorbol-12-myristate-13-acetate (PMA)-induced cell model and mammary tumor tissues was examined by Western blotting and immunohistochemistry. The results showed that BI significantly inhibited cell proliferation and DNA synthesis, arrested the distribution of cell cycle at the S phase or decreased proteins related to cell cycle such as cyclin D1 and CDK4, induced apoptosis and increased the expression of p-P38 in MCF-7 cells. BI at low doses (< 50 µmol/L) significantly increased QR activity, decreased the expression of COX-2 protein and prostaglandin E2 (PEG2) release in cell models. In addition, BI also significantly decreased the expression of COX-2 protein in rat mammary tumor tissues. Therefore, our findings indicate that BI possesses inhibitory proliferation of breast cancer cells through down-regulation of COX-2 activity.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Inibidores de Ciclo-Oxigenase 2/farmacologia , Ciclo-Oxigenase 2/efeitos dos fármacos , Norisoprenoides/farmacologia , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Carcinoma Hepatocelular/enzimologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Neoplasias Hepáticas/enzimologia , Células MCF-7 , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/enzimologia , Neoplasias Mamárias Experimentais/patologia , Camundongos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Norisoprenoides/administração & dosagem , Ratos
3.
Ginekol Pol ; 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37162140

RESUMO

OBJECTIVES: To investigate the prevalence and influencing factors of stress urinary incontinence (SUI) within 6-8 weeks postpartum in Jiangsu Province. MATERIAL AND METHODS: We designed a multi-center cross-sectional study involving seven hospitals in Jiangsu province, and enrolled women who underwent postpartum examination at 6-8 weeks in these hospitals between July 2019 and June 2021. According to the presence or absence of SUI, the enrolled patients were divided into two groups: the SUI group and the non-SUI group, respectively. We assessed the general health status, noted the details of delivery, and checked the pelvic floor electromyographic parameters of the postpartum women in both groups. RESULTS: Among 6,302 cases of postpartum women in Jiangsu province, there were 1,579 cases of SUI, with a prevalence of 25.06%. The prevalence of SUI increased significantly with age, BMI, increasing parity, coexisting constipation, organ prolapse, and diastasis recti abdominis. Compared to the non-SUI group, the SUI group had a lower mean value of the pre-baseline rest phase, shorter rise and fall times of fast muscle contractions, and a lower mean value of the endurance contraction phase. Multiple regression analysis revealed associations with weight (especially overweight and obesity), coexisting organ prolapse, constipation, parity, gestational week of delivery, mode of delivery, and mean value of endurance contraction phase. CONCLUSIONS: The prevalence of postpartum stress urinary incontinence in Jiangsu Province was 25.06%, and was linked to being overweight, parity > 2, coexisting organ prolapse, constipation, and a decrease in the mean value of the endurance contraction phase of the electromyograph. In this report, we offer a theoretical basis for the effective prevention of postpartum SUI clinically.

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