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1.
Sensors (Basel) ; 23(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36904968

RESUMO

This paper researches the recognition of modulation signals in underwater acoustic communication, which is the fundamental prerequisite for achieving noncooperative underwater communication. In order to improve the accuracy of signal modulation mode recognition and the recognition effects of traditional signal classifiers, the article proposes a classifier based on the Archimedes Optimization Algorithm (AOA) and Random Forest (RF). Seven different types of signals are selected as recognition targets, and 11 feature parameters are extracted from them. The decision tree and depth obtained by the AOA algorithm are calculated, and the optimized random forest after the AOA algorithm is used as the classifier to achieve the recognition of underwater acoustic communication signal modulation mode. Simulation experiments show that when the signal-to-noise ratio (SNR) is higher than -5dB, the recognition accuracy of the algorithm can reach 95%. The proposed method is compared with other classification and recognition methods, and the results show that the proposed method can ensure high recognition accuracy and stability.

2.
Aging (Albany NY) ; 12(4): 3298-3311, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-32062612

RESUMO

BACKGROUND: Berberine (BBR) has gained considerable attention because of its anti-tumor activity. BBR can induce apoptosis of acute lymphoblastic leukemia (ALL) cells through the MDM2/p53 pathway. However, the effects of BBR on those ALL patients with p53 deficiency remain unclear. RESULTS: We found that BBR reduced ALL cell viability and induced apoptosis in p53-null EU-4 and p53-mutant EU-6 cells by downregulating X-linked inhibitor of apoptosis protein (XIAP), which is increased in ALL tissues and cells. BBR-induced cell apoptosis was attenuated by inhibition of XIAP that was controlled by PIM-2. Mechanistic studies showed that BBR treatment induced an enhancement of miR-24-3p. PIM-2 is a direct target of miR-24-3p. Blockade of PIM-2 or miR-24-3p reversed BBR-induced cell apoptosis. In vivo studies, BBR remarkably alleviated leukemia conditions in a EU4 xenograft mouse model, whereas inhibition of miR-24-3p significantly reversed the effects of BBR in the leukemia condition. CONCLUSIONS: miR-24-3p/PIM-2/XIAP signaling contributes to BBR-mediated leukemia mitigation in p53-defect ALL, which should be further developed as a treatment strategy in ALL patients with p53 deficiency. METHODS: Cell viability and apoptosis were determined using CCK-8 and TUNEL assays, respectively. The dual-luciferase reporter gene system was used to determine the interaction between miR-24-3p and 3'-untranslated regions (UTRs) of PIM-2.


Assuntos
Apoptose/efeitos dos fármacos , Berberina/farmacologia , MicroRNAs/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Animais , Medula Óssea/efeitos dos fármacos , Medula Óssea/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Camundongos , Regulação para Cima/efeitos dos fármacos
3.
Life Sci ; 242: 117228, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31881227

RESUMO

AIMS: Berberine (BBR) is reported to induce apoptosis and inhibit migration of leukemic cells, but the underlying pharmacological mechanisms have not been fully revealed. This study aims to investigate the possible mechanisms from the perspective of autophagy. MAIN METHODS: P-53-null leukemic cell lines Jurkat and U937 were used for the in vitro study. MDC staining was used for observation of autophagy in leukemic cells, and Western blot analysis was for determination of the expression levels of autophagy-associated proteins. Apoptosis of the leukemic cells was detected by flow cytometry. Cellular location of MDM2 was observed with immunofluorescence staining. Ubiquitination of MDM2 was assessed by immunoprecipitation. Male 6-8-week-old NOD/SCID mice were used for evaluating the effect of BBR on chemotherapy sensitivity in vivo. KEY FINDINGS: BBR induced autophagy in p53-null leukemic cells, which was inhibited by autophagy inhibitors 3-methyladenine. 3-methyladenine also inhibited BBR-induced apoptosis in leukemic cells. In addition, BBR not only decreased MDM2 mRNA expression, but also enhanced MDM2 self-ubiquitination in leukemic cells. Forced overexpression of MDM2 reversed the effect of BBR on autophagy and apoptosis. Furthermore, BBR promoted doxorubicin-induced autophagy and cell death in the leukemic cells and overexpression of MDM2 suppressed these effects. In vivo, BBR combined with doxorubicin achieved better therapeutic effect than doxorubicin alone. SIGNIFICANCE: MDM2 inhibits autophagy and apoptosis in leukemic cells in a p53-independent manner. BBR induces autophagy in p53-null leukemic cells through downregulating MDM2 expression at both transcriptional and post-transcriptional levels, which may contribute to the anti-cancer effect of BBR in leukemia.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Berberina/farmacologia , Células Jurkat/efeitos dos fármacos , Leucemia Experimental/tratamento farmacológico , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Células U937/efeitos dos fármacos , Animais , Western Blotting , Citometria de Fluxo , Imunofluorescência , Humanos , Células Jurkat/metabolismo , Leucemia Experimental/metabolismo , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Transplante de Neoplasias , Reação em Cadeia da Polimerase em Tempo Real , Células U937/metabolismo , Ubiquitinação
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