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1.
J Am Chem Soc ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767649

RESUMO

Heterophase nanomaterials have sparked significant research interest in catalysis due to their distinctive properties arising from synergistic effects of different components and the formed phase boundary. However, challenges persist in the controlled synthesis of heterophase intermetallic compounds (IMCs), primarily due to the lattice mismatch of distinct crystal phases and the difficulty in achieving precise control of the phase transitions. Herein, orthorhombic/cubic Ru2Ge3/RuGe IMCs with engineered boundary architecture are synthesized and anchored on the reduced graphene oxide. The Ru2Ge3/RuGe IMCs exhibit excellent hydrogen evolution reaction (HER) performance with a high current density of 1000 mA cm-2 at a low overpotential of 135 mV. The presence of phase boundaries enhances charge transfer and improves the kinetics of water dissociation while optimizing the processes of hydrogen adsorption/desorption, thus boosting the HER performance. Moreover, an anion exchange membrane electrolyzer is constructed using Ru2Ge3/RuGe as the cathode electrocatalyst, which achieves a current density of 1000 mA cm-2 at a low voltage of 1.73 V, and the activity remains virtually undiminished over 500 h.

2.
Angew Chem Int Ed Engl ; 63(25): e202405173, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38622784

RESUMO

Constructing amorphous/intermetallic (A/IMC) heterophase structures by breaking the highly ordered IMC phase with disordered amorphous phase is an effective way to improve the electrocatalytic performance of noble metal-based IMC electrocatalysts because of the optimized electronic structure and abundant heterophase boundaries as active sites. In this study, we report the synthesis of ultrathin A/IMC PtPbBi nanosheets (NSs) for boosting hydrogen evolution reaction (HER) and alcohol oxidation reactions. The resulting A/IMC PtPbBi NSs exhibit a remarkably low overpotential of only 25 mV at 10 mA cm-2 for the HER in an acidic electrolyte, together with outstanding stability for 100 h. In addition, the PtPbBi NSs show high mass activities for methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR), which are 13.2 and 14.5 times higher than those of commercial Pt/C, respectively. Density functional theory calculations demonstrate that the synergistic effect of amorphous/intermetallic components and multimetallic composition facilitate the electron transfer from the catalyst to key intermediates, thus improving the catalytic activity of MOR. This work establishes a novel pathway for the synthesis of heterophase two-dimensional nanomaterials with high electrocatalytic performance across a wide range of electrochemical applications.

3.
Inflamm Res ; 71(10-11): 1327-1345, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35962798

RESUMO

BACKGROUND AND OBJECTIVE: Acute lung injury (ALI)/ acute respiratory distress syndrome (ARDS) was increasingly recognized as one of the most severe acute hyperimmune response of coronavirus disease 2019 (COVID-19). Clofazimine (CFZ) has attracted attention due to its anti-inflammatory property in immune diseases as well as infectious diseases. However, the role and potential molecular mechanism of CFZ in anti-inflammatory responses remain unclear. METHODS: We analyze the protein expression profiles of CFZ and LPS from Raw264.7 macrophages using quantitative proteomics. Next, the protective effect of CFZ on LPS-induced inflammatory model is assessed, and its underlying mechanism is validated by molecular biology analysis. RESULTS: LC-MS/MS-based shotgun proteomics analysis identified 4746 (LPS) and 4766 (CFZ) proteins with quantitative information. The key proteins and their critical signal transduction pathways including TLR4/NF-κB/HIF-1α signaling was highlighted, which was involved in multiple inflammatory processes. A further analysis of molecular biology revealed that CFZ could significantly inhibit the proliferation of Raw264.7 macrophages, decrease the levels of TNF-α and IL-1ß, alleviate lung histological changes and pulmonary edema, improve the survival rate, and down-regulate TLR4/NF-κB/HIF-1α signaling in LPS model. CONCLUSION: This study can provide significant insight into the proteomics-guided pharmacological mechanism study of CFZ and suggest potential therapeutic strategies for infectious disease.


Assuntos
Lesão Pulmonar Aguda , Tratamento Farmacológico da COVID-19 , Síndrome do Desconforto Respiratório , Animais , Camundongos , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Cromatografia Líquida , Clofazimina , Lipopolissacarídeos/farmacologia , Pulmão/patologia , NF-kappa B/metabolismo , Proteômica , Espectrometria de Massas em Tandem , Receptor 4 Toll-Like/metabolismo
4.
Thorac Cancer ; 12(18): 2439-2448, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34337871

RESUMO

PURPOSE: The objective of our study was to investigate the epidemiologic characteristics and prognostic factors in patients with pulmonary acinar cell carcinoma (PACC). METHODS: PACC patients diagnosed between 1975 and 2016 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. The trend in PACC incidence was assessed using joinpoint regression software. Overall survival (OS) and disease-specific survival (DSS) were evaluated using the Kaplan-Meier method and log-rank test. Univariate and multivariate Cox regression analysis was performed to identify the independent prognostic factors for OS and DSS. Nomograms to predict survival possibilities were constructed based on the identified independent prognostic factors. RESULTS: A total of 2918 patients were identified with PACC. The mean age was 65.2 ± 8.95 years with a female to male of 1.6:1. The incidence of PACC steadily increased by an annual percentage change (APC) of 3.2% (95% CI 2.1-4.4, p < 0.05). Multivariate Cox regression analysis revealed that age, gender, race, stage, grade, tumor size, number of positive lymph nodes, surgery, and chemotherapy were independent prognostic factors for survival. Nomograms specifically for PACC were constructed to predict 1- and 5-year OS and DSS possibility, respectively. The concordance index (C-index) and calibration plots showed the established nomograms had robust and accurate performance. CONCLUSION: PACC was rare but the incidence has been steadily increasing over the past four decades. Survival has improved in recent years. Surgery or chemotherapy could provide better OS and DSS. The established nomograms specifically for PACC were robust and accurate in predicting 1- and 5-year OS and DSS.


Assuntos
Carcinoma de Células Acinares/epidemiologia , Neoplasias Pulmonares/epidemiologia , Adulto , Idoso , Carcinoma de Células Acinares/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Programa de SEER , Taxa de Sobrevida , Estados Unidos/epidemiologia
5.
Immunol Lett ; 237: 17-26, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34192561

RESUMO

OBJECTIVE: To understand the characteristics of DNA methyltransferase 3a (DNMT3a) in thymoma associated Myasthenia Gravis reveal its transcriptional regulator network as while as analyze the effect of DNMT3a on Rel/ nuclear factor-kappaB family (RelA/RelB) and its downstream autoimmune regulatory factor (Aire). METHODS: Tissues of 30 patients with thymoma, with or without myasthenia gravis (MG), were collected and the DNMT3a protein expression were evaluated through immunohistochemistry. We performed mRNA expression profiling microarray detection and analysis, and integrated the analysis by constructing protein-protein interaction networks and the integration with other database. We identified molecular difference between low and high DNMT3a in the thymoma by heatmap. We also performed PCR validation in thymoma tissues. The DNMT3a-shRNA plasmid was transfected into TEC cells, and these cells were treated with 5-aza-2-deoxycytidine, a blocker of DNMT3a. After the down-regulation of DNMT3a in TEC cells, the transcript and protein levels of RelA, RelB, Aire, and CHRNA3 were evaluated by western blotting. In addition, changes in gene expression profiles were screened through microarray technology. We performed differential gene analysis in the thymoma cohort by heatmap with R (v.4.3.0) software. RESULTS: In 30 matched tissue specimens, the expression of DNMT3a protein in thymoma with MG was lower than that in thymoma. Through mRNA expression profiling analysis, we constructed a co-expression network of DNMT3a and found direct interaction between IKZF1 and DNMT3a, and this co-expression relationship was overlappted with Cistrome DB database. We found up-regulation of 149 mRNAs and repression of 177 mRNAs in thymoma with MG compared with thymoma. Gene ontology and pathway analysis show the involvement of a multitude of genes in the mis-regulation of MG-related pathways. RNA interference significantly reduced the level of mRNA of DNMT3a, which proved that plasmid DNMT3a was effective. In comparison to the control group, the levels of DNMT3a, Aire, and CHRNA3 mRNA and protein in TEC cells transfected with DNMT3a-shRNA interference plasmid were significantly decreased, while the expression level of RelA and RelA/RelB was significantly increased. CONCLUSIONS: Our study reveals the DNMT3a-NF-κB pathway has a major effect on MG, and can be used as a marker for diagnosis as well as a target for MG treatment.


Assuntos
DNA Metiltransferase 3A/biossíntese , Células Epiteliais/metabolismo , Regulação Neoplásica da Expressão Gênica , Miastenia Gravis/metabolismo , NF-kappa B/biossíntese , Proteínas de Neoplasias/biossíntese , Interferência de RNA , Timoma/metabolismo , Timo/metabolismo , Neoplasias do Timo/metabolismo , Adolescente , Adulto , DNA Metiltransferase 3A/antagonistas & inibidores , DNA Metiltransferase 3A/genética , Decitabina/farmacologia , Ontologia Genética , Humanos , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/etiologia , Miastenia Gravis/genética , NF-kappa B/genética , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Mapas de Interação de Proteínas , RNA Neoplásico/genética , RNA Interferente Pequeno/genética , Receptores Nicotínicos/biossíntese , Receptores Nicotínicos/genética , Timoma/complicações , Timoma/genética , Neoplasias do Timo/complicações , Neoplasias do Timo/genética , Análise Serial de Tecidos , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Transcriptoma , Proteína AIRE
6.
Exp Ther Med ; 18(5): 3525-3533, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31602229

RESUMO

Breast cancer is the most common cancer in women worldwide, and the incidence and mortality rates are increasing every year. Dysregulation of microRNAs (miRNAs or miRs) is an important step in the initiation and development of breast cancer. Previous studies demonstrated that miR-205-5p is closely associated with occurrence and development of breast cancer; however, underlying mechanisms remain unclear. In the present study, reverse transcription-quantitative polymerase chain reaction assays were used to analyze miR-195-5p and endoplasmic reticulum protein 29 (ERp29) levels in breast cancer and matched normal tissues. Western blot analysis was performed to analyze ERp29 and heat shock protein 27 (HSP27) protein expression levels. Cell viability, flow cytometry and luciferase reporter assay were used to examine cell proliferation, apoptosis and direct miRNA-mRNA binding, respectively. The results revealed that miR-205-5p expression in breast cancer tissues and cell lines was decreased compared with normal tissues and a normal cell line. Overexpression of miR-205-5p significantly augmented cytotoxicity effects of gemcitabine treatment in MDA-MB-231 and BT549 cells. It was observed that miR-205-5p negatively regulated ERp29 expression in breast cancer cells. Dual luciferase assays confirmed that ERp29 was a target of miR-205-5p in breast cancer cells. Additionally, following the established gemcitabine-resistant MDA-MB-231 cells (MDA-MB-231/GEM), ERp29 and HSP27 expression was upregulated and miR-205-5p was downregulated compared with parental cells. Overexpression of miR-205-5p reversed gemcitabine resistance in MDA-MB-231/GEM cells. In conclusion, the present study indicated that miR-205-5p may inhibit gemcitabine resistance in breast cancer cells via inhibition of ERp29 expression.

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