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1.
Opt Express ; 31(16): 25648-25661, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710446

RESUMO

Bandpass microwave photonic filter (MPF) can be achieved based on the well-known phase to intensity conversion method by using phase modulation and single micro-ring resonator (MRR) notch filter. Since MRR could introduce residual phase in handling one optical sideband, the out-of-band radio frequency (RF) rejection ratio and the shape factor of the bandpass MPF are very limited. Here, by introducing another MRR to handle the other optical sideband, the residual phase can be greatly suppressed, thus the filter's performance can be greatly improved. The proposed bandpass MPF was both verified theoretically and experimentally. Compared with the single MRR, the out-of-band RF rejection ratio and the shape factor were improved by 20 dB and 1.67, respectively. Furthermore, the bandpass MPF's bandwidth is reconfigurable by adjusting the optical carrier's frequency or the two MRRs' amplitude coupling coefficients. The bandpass MPF's center frequency is also tunable by changing the resonant wavelengths of two MRRs in the opposite direction simultaneously. Experimentally, bandwidth reconfiguration from 0.38 GHz to 15.74 GHz, the shape factor optimization from 2 to 1.23, and frequency tuning from 4 GHz to 21.5 GHz were achieved. We believe that the proposed bandpass MPF has great potential for microwave photonic signal processing.

2.
Biochem Biophys Res Commun ; 583: 184-191, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34749235

RESUMO

Triple-negative breast cancer (TNBC) lacks a recognized therapeutic molecular target and has an unfavorable prognosis. (20S)-Protopanaxatriol (g-PPT, PPT) is an active metabolite extracted from ginseng. Accumulating evidence suggests that it has good anti-cancer activity in vivo and in vitro. In this study, we aimed to elucidate the anti-tumor effects of PPT in TNBC cells and tumor-bearing mice, as well as the relevant molecular mechanisms of autophagy and apoptosis. In vitro, we have found that PPT is capable of inducing non-protective autophagy and apoptosis, thus exerting some anti-proliferative and anti-migration activity in TNBC cells. And in vivo, the therapeutic effects of PPT were evaluated by xenograft mouse models. The potential binding mode of PPT and Akt was predicted by molecular docking. Our findings indicated that PPT treatment induced non-protective autophagy in TNBC cells by inhibiting the Akt/mTOR signaling pathway. Therefore, PPT may be a potential treatment for TNBC in the future.

3.
Curr Med Sci ; 39(1): 37-43, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30868489

RESUMO

This study aimed to verify the effects of berberine (BBR) on the fat metabolism proteins involved in the sirtuin 3 (SIRT3)/adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/acetyl-CoA carboxylase (ACC) pathway in the liver tissues of rats with high-fat diet (HFD)-induced non-alcoholic fatty liver disease (NAFLD). Forty-eight rats were randomly divided into the normal control (NC) group, HFD group or BBR group, with 16 rats in each group. After 8 and 16 weeks of treatment, serum and liver samples were collected. Subsequently, body parameters, biochemical parameters and liver pathology were examined. The expression levels of proteins involved in the SIRT3/AMPK/ACC pathway in the liver were detected by Western blotting. After 8 and 16 weeks of a HFD, the successful establishment of rat models with different degrees of NAFLD was confirmed by hematoxylin and eosin (H&E) and Oil Red O staining. NAFLD rat models exhibited obesity and hyperlipidemia, and the protein expression levels of SIRT3, p-AMPK, p-ACC, and CPT-1A in the liver were significantly decreased compared to those in the NC group. The concurrent administration of BBR with the HFD effectively improved serum and liver lipid profiles and ameliorated liver injury. Furthermore, the protein expression levels of SIRT3, p-AMPK, p-ACC, and CPT-1A in the liver were significantly increased in the BBR group as compared with those in the HFD group. In conclusion, our data suggest that the mechanism by which BBR ameliorates HFD-induced hepatic steatosis may be related to the activation of the SIRT3/AMPK/ACC pathway in the liver.


Assuntos
Berberina/administração & dosagem , Dieta Hiperlipídica/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade/induzido quimicamente , Transdução de Sinais/efeitos dos fármacos , Acetil-CoA Carboxilase/metabolismo , Adenilato Quinase/metabolismo , Animais , Berberina/farmacologia , Carnitina O-Palmitoiltransferase/metabolismo , Modelos Animais de Doenças , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/complicações , Obesidade/metabolismo , Fosforilação/efeitos dos fármacos , Distribuição Aleatória , Ratos , Sirtuínas/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-29675053

RESUMO

The present study investigates the potential therapeutic mechanism underlying the effects of the Chinese herbal formula Hongqijiangzhi Fang (HJF) on nonalcoholic fatty liver disease (NAFLD) in rats. Male Sprague Dawley (SD) rats were randomly divided into 4 groups (n = 8): control group was fed a normal diet, three other groups were fed high-fat diets (HFD), and the two treatment groups were intragastrically given a compound probiotic or HJF during the molding time. After 16 w, related indices were detected. The results showed that HJF significantly reduced abdominal aorta serum cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), IL-1ß, and IL-18, portal venous serum lipopolysaccharide (LPS), and liver TC and TG levels in HFD-fed rats. HJF ameliorated hepatic steatosis in the liver and improved the intestinal barrier in HFD-fed rats. Activation of the NLRP3 inflammasome was reduced by HJF in HFD-fed rats. Additionally, the abundances of A. muciniphila (Verrucomicrobiaceae), F. rappini (Helicobacteraceae), and Enterobacteriaceae bacteria significantly decreased in HJF-treated HFD-fed rats. In conclusion, these result suggested that the Chinese herbal formula HJF reduced hepatic steatosis maybe through decreasing certain gut bacteria (such as Enterobacteriaceae bacteria and F. rappini), alleviating intestinal endotoxemia and reducing NLRP3 inflammasome activation.

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