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1.
Nat Commun ; 15(1): 2110, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454003

RESUMO

Pilot-diesel-ignition ammonia combustion engines have attracted widespread attentions from the maritime sector, but there are still bottleneck problems such as high unburned NH3 and N2O emissions as well as low thermal efficiency that need to be solved before further applications. In this study, a concept termed as in-cylinder reforming gas recirculation is initiated to simultaneously improve the thermal efficiency and reduce the unburned NH3, NOx, N2O and greenhouse gas emissions of pilot-diesel-ignition ammonia combustion engine. For this concept, one cylinder of the multi-cylinder engine operates rich of stoichiometric and the excess ammonia in the cylinder is partially decomposed into hydrogen, then the exhaust of this dedicated reforming cylinder is recirculated into the other cylinders and therefore the advantages of hydrogen-enriched combustion and exhaust gas recirculation can be combined. The results show that at 3% diesel energetic ratio and 1000 rpm, the engine can increase the indicated thermal efficiency by 15.8% and reduce the unburned NH3 by 89.3%, N2O by 91.2% compared to the base/traditional ammonia engine without the proposed method. At the same time, it is able to reduce carbon footprint by 97.0% and greenhouse gases by 94.0% compared to the traditional pure diesel mode.

2.
J Ethnopharmacol ; 322: 117576, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38104880

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Type 1 diabetes mellitus (T1DM) results from insulin deficiency due to the destruction of pancreatic ß-cells. Previously, our studies showed that inhibition of Keap1/Nrf2 signaling pathway promoted the onset of T1DM, which suggests that finding drugs that can activate the Keap1/Nrf2 signaling may be a promising therapeutic strategy for the T1DM treatment. Astragalus membranaceus (Fisch.) Bunge is a common traditional Chinese medicine that has been frequently applied in Chinese clinics for the treatment of diabetes and other diseases. Formononetin (FMNT), one of the major isoflavonoid constituents isolated from this herbal medicine, possesses diverse pharmacological benefits and T1DM therapeutic potential. However, the exact molecular mechanisms underlying the action of FMNT in ameliorating T1DM have yet to be fully elucidated. AIMS OF THE STUDY: This study is to investigate the regulation of FMNT on the Keap1/Nrf2 signaling pathway to ameliorate T1DM based on network pharmacology approach combined with experimental validation. MATERIALS AND METHODS: A mouse-derived pancreatic islet ß-cell line (MIN6) was used for the in vitro studies. An alloxan (ALX)-induced T1DM model in wild-type and Nrf2 knockout (Nrf2-/-) C57BL/6J mice were established for the in vivo experiments. The protective effects of FMNT against ALX-stimulated MIN6 cell injury were evaluated using MTT, EdU, apoptosis and comet assays. The levels of blood glucose in mice were measured by using a blood monitor and test strips. The protein expression was detected by Western blot analysis. Furthermore, the binding affinity of FMNT to Keap1 was evaluated using cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS) assay, and solvent-induced protein precipitation (SIP) assay. The interaction pattern between FMNT and Keap1 was assessed by molecular docking and molecular dynamics simulation techniques. RESULTS: Network pharmacology analysis revealed that FMNT exerted its therapeutic effect against T1DM by mainly regulating oxidative stress response-associated signaling molecules and pathways, such as Nrf2 regulating anti-oxidant/detoxification enzymes and Keap1-Nrf2 signaling pathway. The in vivo results showed that FMNT significantly deceased the ALX-induced high blood glucose levels and conversely increased the ALX-induced low insulin contents. In vitro, FMNT markedly protected MIN6 cells from ALX-induced cytotoxicity, proliferation inhibition and DNA damage and reduced the ALX-stimulated cell apoptosis. FMNT also inhibited ALX-induced overproduction of intracellular ROS to alleviate oxidative stress. In addition, FMNT could bind to Keap1 to notably activate the Keap1/Nrf2 signaling to upregulate Nrf2 expression and promote the Nrf2 translocation from the cytoplasm to the nucleus, resulting in enhancing the expression of antioxidant proteins HO-1 and NQO1. Inhibition of Keap1/Nrf2 signaling by ALX was also markedly abolished in the cells and mice exposed to FMNT. Moreover, these effects of FMNT in ameliorating T1DM were not observed in Nrf2-/- mice. CONCLUSIONS: This study demonstrates that FMNT could bind to Keap1 to activate the Keap1/Nrf2 signaling to prevent intracellular ROS overproduction, thereby attenuating ALX-induced MIN6 cell injury and ameliorating ALX-stimulated T1DM. Results from this study might provide evidence and new insight into the therapeutic effect of FMNT and indicate that FMNT is a promising candidate agent for the treatment of T1DM in clinics.


Assuntos
Diabetes Mellitus Tipo 1 , Insulinas , Isoflavonas , Camundongos , Animais , Diabetes Mellitus Tipo 1/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Astragalus propinquus , Glicemia , Simulação de Acoplamento Molecular , Farmacologia em Rede , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Transdução de Sinais , Insulinas/metabolismo , Insulinas/farmacologia
3.
Free Radic Biol Med ; 208: 530-544, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37717793

RESUMO

Colon cancer continues to be a prevalent gastrointestinal malignancy with a bleak prognosis. The induction of ferroptosis, a new form of regulated cell death, has emerged as a potentially effective strategy for the treatment of colon cancer. However, numerous colon cancer cells display resistance to ferroptosis induced by erastin, a well-established ferroptosis inducer. Finding drugs that can enhance the susceptibility of colon cancer cells to erastin is of utmost importance. This study aimed to examine the synergistic therapeutic impact of combining erastin with a bioactive flavonoid compound luteolin on the ferroptosis-mediated suppression of colon cancer. Human colon cancer HCT116 and SW480 cells were used for the in vitro studies and a xenograft of colon cancer model in BALB/c nude mice was established for the in vivo experiments. The results showed that combinative treatment of luteolin and erastin effectively inhibited the viability and proliferation of colon cancer cells. Luteolin and erastin cotreatment synergistically induced ferroptosis, concomitant with a reduction in glutathione and an elevation in lipid peroxides. In vivo, combinative treatment of luteolin and erastin exhibited a pronounced therapeutic effect on xenografts of colon cancer, characterized by a significant induction of ferroptosis. Mechanistically, luteolin in combination with erastin synergistically reduced the expression of glutathione peroxidase 4 (GPX4), an antioxidase overexpressed in colon cancer cells. Furthermore, luteolin and erastin cotreatment significantly upregulated the expression of hypermethylated in cancer 1 gene (HIC1), a transcriptional repressor also recognized as a tumor suppressor. HIC1 overexpression notably augmented the suppression of GPX4 expression and facilitated ferroptotic cell death. In contrast, HIC1 silencing attenuated the inhibition of GPX4 expression and eliminated the ferroptosis. Conclusively, these results clearly demonstrated that luteolin acts synergistically with erastin and renders colon cancer cells vulnerable to ferroptosis through the HIC1-mediated inhibition of GPX4 expression, which may act as a promising therapeutic strategy.


Assuntos
Neoplasias do Colo , Ferroptose , Camundongos , Animais , Humanos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Ferroptose/genética , Luteolina/farmacologia , Camundongos Nus , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Fatores de Transcrição Kruppel-Like
4.
Front Pharmacol ; 14: 1111912, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36755950

RESUMO

Colon cancer is a highly malignant cancer with poor prognosis. Astragalus membranaceus (Fisch.) Bunge (Huang Qi in Chinese, HQ), a well-known Chinese herbal medicine and a popular food additive, possesses various biological functions and has been frequently used for clinical treatment of colon cancer. However, the underlying mechanism is not fully understood. Isoflavonoids, including formononetin (FMNT) and calycosin (CS), are the main bioactive ingredients isolated from HQ. Thus, this study aimed to explore the inhibitory effects and mechanism of HQ, FMNT and CS against colon cancer by using network pharmacology coupled with experimental validation and molecular docking. The network pharmacology analysis revealed that FMNT and CS exerted their anticarcinogenic actions against colon cancer by regulating multiple signaling molecules and pathways, including MAPK and PI3K-Akt signaling pathways. The experimental validation data showed that HQ, FMNT and CS significantly suppressed the viability and proliferation, and promoted the apoptosis in colon cancer Caco2 and HT-29 cells. HQ, FMNT and CS also markedly inhibited the migration of Caco2 and HT-29 cells, accompanied by a marked increase in E-cadherin expression, and a notable decrease in N-cadherin and Vimentin expression. In addition, HQ, FMNT and CS strikingly decreased the expression of ERK1/2 phosphorylation (p-ERK1/2) without marked change in total ERK1/2 expression. They also slightly downregulated the p-Akt expression without significant alteration in total Akt expression. Pearson correlation analysis showed a significant positive correlation between the inactivation of ERK1/2 signaling pathway and the HQ, FMNT and CS-induced suppression of colon cancer. The molecular docking results indicated that FMNT and CS had a strong binding affinity for the key molecules of ERK1/2 signaling pathway. Conclusively, HQ, FMNT and CS exerted good therapeutic effects against colon cancer by mainly inhibiting the ERK1/2 signaling pathway, suggesting that HQ, FMNT and CS could be useful supplements that may enhance chemotherapeutic outcomes and benefit colon cancer patients.

5.
Molecules ; 27(12)2022 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-35744915

RESUMO

Renifolin F is a prenylated chalcone isolated from Shuteria involucrata, a traditional minority ethnic medicine used to treat the respiratory diseases and asthma. Based on the effects of the original medicine plant, we established an in vivo mouse model of allergic asthma using ovalbumin (OVA) as an inducer to evaluate the therapeutic effects of Renifolin F. In the research, mice were sensitized and challenged with OVA to establish an allergic asthma model to evaluate the effects of Renifolin F on allergic asthma. The airway hyper-reactivity (AHR) to methacholine, cytokine levels, ILC2s quantity and mircoRNA-155 expression were assessed. We discovered that Renifolin F attenuated AHR and airway inflammation in the OVA-induced asthmatic mouse model by inhibiting the regulation of ILC2s in the lung, thereby, reducing the upstream inflammatory cytokines IL-25, IL-33 and TSLP; the downstream inflammatory cytokines IL-4, IL-5, IL-9 and IL-13 of ILC2s; and the co-stimulatory factors IL-2 and IL-7; as well as the expression of microRNA-155 in the lung. The findings suggest a therapeutic potential of Renifolin F on OVA-induced airway inflammation.


Assuntos
Asma , Hipersensibilidade , MicroRNAs , Animais , Asma/induzido quimicamente , Asma/tratamento farmacológico , Asma/metabolismo , Líquido da Lavagem Broncoalveolar , Chalcona/farmacologia , Chalcona/uso terapêutico , Citocinas/metabolismo , Modelos Animais de Doenças , Imunidade Inata , Inflamação , Pulmão/metabolismo , Linfócitos/metabolismo , Camundongos , MicroRNAs/genética , MicroRNAs/uso terapêutico , Ovalbumina/efeitos adversos
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4002-4007, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018877

RESUMO

In this paper, a real time physiological signal classification system with an integrated ultra-low power collaborative neural network classifier is presented. The developed system includes a specially designed system-on-chip (SoC) and a wireless communication module that transmits classification results to a smartphone app as a convenient user interface in real-time training. The customized SoC provides ultra-low-power and low-latency sensing and classification on physiological signals, e.g. EMG and ECG. A special collaborative neural network classifier was implemented to allow multiple chips to collaborate on classification. As a result, only low dimensional data is being transmitted over the network, significantly reducing data communication across multiple modules. A demonstration of EMG based gesture classification shows 1100X less power consumption from the developed SoC compared with conventional embedded solutions. The transmission of only low dimensional data from the collaborative neural network classifier leads to a 50X reduction of data communication and associated energy for multiple sensing cites.


Assuntos
Algoritmos , Dispositivos Eletrônicos Vestíveis , Gestos , Redes Neurais de Computação , Processamento de Sinais Assistido por Computador
7.
Data Brief ; 28: 104837, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31828193

RESUMO

Scaled model experiments are very useful for reducing time, cost and energy consumption in marine diesel engine development. This data article is based on the research work which examines the potential of scaled model experiments for marine low-speed diesel engines. Two engines of 340 and 520 mm bore diameters are employed to conduct this numerical scaling work based on three diesel combustion scaling laws. Data on similarity of peak swirl ratio, heat transfer losses, liquid and vapor penetration length, ignition delay, in-cylinder peak temperature, peak carbon monoxide (CO), peak hydrocarbon (HC) and carbon dioxide (CO2) emissions for various fuel injection timing are provided. The data in this paper are valuable reference for researchers or engineers who attempt to conduct scaled model experiments in marine diesel engine development.

8.
Sci Total Environ ; 574: 1432-1438, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27535570

RESUMO

Air pollution in transportation cabins has recently become a public concern. However, few studies assessed the exposure levels of suspected air pollutants including Volatile Organic Compounds (VOCs). This paper studied the exposure levels of in-carriage VOCs (benzene, toluene, ethylbenzene, xylene, styrene, formaldehyde, acetaldehyde, acetone and acrolein) in Shanghai, China and estimated the health risk in different conditions. The results indicated that VOCs concentrations in metro carriages varied from different train models, due to the difference in carriage size and ventilation system. The concentrations of aromatic VOCs in old metro carriage were 1-2 times higher than the new ones, as better paintings were used in new trains. Poor air circulation and ventilation in the underground track was likely to be the cause of higher VOCs levels (~10%) than the above-ground track. Lower aromatic compounds levels and higher carbonyls levels were observed in metro carriages at suburban areas than those at urban areas, likely due to less aromatic emission sources and more carbonyls emission sources in suburban areas. Acetone and acrolein were found to increase from 7.71 to 26.28µg/m3 with number of commuters increasing from 40 to 200 in the carriages. According to the acceptable level proposed by the World Health Organization (1×10-6-1×10-5), the life carcinogenic risk of commuters by subway (8.5×10-6-4.8×10-5) was little above the acceptable level in Shanghai. Further application of our findings is possible to act as a reference in facilitating regulations for metro systems in other cities around world, so that in-carriage air quality might be improved.


Assuntos
Poluentes Atmosféricos/análise , Exposição por Inalação/análise , Meios de Transporte , Compostos Orgânicos Voláteis/análise , Poluição do Ar em Ambientes Fechados , China , Cidades , Monitoramento Ambiental , Humanos , Medição de Risco
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