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1.
Chemosphere ; 345: 140530, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37890791

RESUMO

A template-free pyrolysis route has been developed using condensation-assembly precursors made of trimethoxyboroxane (TMB) and melamine (M) to cater the requirements of an industrial real-world environment. The precursors contain abundant B-N bonds and exhibit a high level of interconnectivity, resulting in 3D-PBN with enhanced mechanical properties and the ability to be easily customized in terms of shape. Moreover, 3D-PBN demonstrates rapid adsorption kinetics and excellent reusability, efficiently removing up to 270% of its own weight of fuel within 30 s and being readily regenerated through simple calcination. Even after undergoing 50 cycles, the mechanical properties remain at a remarkable 80%, while the adsorption performance exceed 95%. Furthermore, a comprehensive analysis of thermal behavior from precursor to 3D-PBN has been conducted, leading to the proposal of a molecular-scale evolution process comprising four major steps. This understanding enables us to control the phase reaction and regulate the composition of the products, which is crucial for determining the characteristics of the final product.


Assuntos
Compostos de Boro , Porosidade , Compostos de Boro/química
3.
Int J Mol Sci ; 17(4): 531, 2016 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-27070592

RESUMO

Although dasatinib is effective in most imatinib mesylate (IMT)-resistant chronic myeloid leukemia (CML) patients, the underlying mechanism of its effectiveness in eliminating imatinib-resistant cells is only partially understood. This study investigated the effects of dasatinib on signaling mechanisms driving-resistance in imatinib-resistant CML cell line K562 (K562R(IMT)). Compared with K562 control cells, exsomal release, the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/ mammalian target of rapamycin (mTOR) signaling and autophagic activity were increased significantly in K562R(IMT) cells and mTOR-independent beclin-1/Vps34 signaling was shown to be involved in exosomal release in these cells. We found that Notch1 activation-mediated reduction of phosphatase and tensin homolog (PTEN) was responsible for the increased Akt/mTOR activities in K562R(IMT) cells and treatment with Notch1 γ-secretase inhibitor prevented activation of Akt/mTOR. In addition, suppression of mTOR activity by rapamycin decreased the level of activity of p70S6K, induced upregulation of p53 and caspase 3, and led to increase of apoptosis in K562R(IMT) cells. Inhibition of autophagy by spautin-1 or beclin-1 knockdown decreased exosomal release, but did not affect apoptosis in K562R(IMT) cells. In summary, in K562R(IMT) cells dasatinib promoted apoptosis through downregulation of Akt/mTOR activities, while preventing exosomal release and inhibiting autophagy by downregulating expression of beclin-1 and Vps34. Our findings reveal distinct dasatinib-induced mechanisms of apoptotic response and exosomal release in imatinib-resistant CML cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Dasatinibe/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Exossomos/efeitos dos fármacos , Mesilato de Imatinib/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Exossomos/metabolismo , Exossomos/patologia , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
4.
Nanomedicine (Lond) ; 11(5): 447-63, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26891593

RESUMO

AIM: To evaluate the response of cells to boron nitride nanotubes (BNNTs) carrying fluorescent probes or drugs in their inner channel by assessment of the cellular localization of the fluorescent cargo, evaluation of the in vitro release and biological activity of a drug (curcumin) loaded in BNNTs. METHODS: Cells treated with curcumin-loaded BNNTs and stimulated with lipopolysaccharide were assessed for nitric oxide release and stimulation of IL-6 and TNF-α. The cellular trafficking of two cell-permeant dyes and a non-cell-permeant dye loaded within BNNTs was imaged. RESULTS: BNNTs loaded with up to 13 wt% fluorophores were internalized by cells and controlled release of curcumin triggered cellular pathways associated with the known anti-inflammatory effects of the drug. CONCLUSION: The overall findings indicate that BNNTs can function as nanocarriers of biologically relevant probes/drugs allowing one to examine/control their local intracellular localization and biochemical effects, leading the way to applications as intracellular nanosensors.


Assuntos
Curcumina/administração & dosagem , Sistemas de Liberação de Medicamentos , Inflamação/tratamento farmacológico , Nanotubos/química , Compostos de Boro/administração & dosagem , Compostos de Boro/química , Curcumina/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Fluorescência , Humanos , Inflamação/patologia , Interleucina-6/biossíntese , Óxido Nítrico/biossíntese , Fator de Necrose Tumoral alfa/biossíntese
5.
Mol Med Rep ; 12(3): 4462-4468, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26081986

RESUMO

The high-mobility group box 1 (HMGB1) protein is a DNA-binding nuclear protein, which is overexpressed in leukemia cells. Cordycepin is characterized by strong antileukemic properties and is regarded as an effective natural compound for leukemia therapy. The aim of the present study was to investigate the impact of HMGB1 knockdown and cordycepin treatment on proliferation, apoptosis, reactive oxygen species (ROS) levels and adhesion of K562 human chronic myeloid leukemia cells. The Cell Counting kit­8 assay was used to determine the proliferation of K562 cells. The cell cycle and apoptosis of K562 cells was determined using flow cytometric analysis. In addition, a cell adhesion assay was performed. Western blotting was used to determine the protein expression of cyclooxygenase 2, Bax, receptor for advanced glycation end-products and Bcl­2. The data collected demonstrated that HMGB1 knockdown combined with cordycepin treatment had significant anti­proliferative and pro­apoptotic effects. In addition, it increased the ROS levels and reduced the adhesion of K562 cells. It was also identified that HMGB1 knockdown had synergistic effects with cordycepin, which aided in accelerating apoptosis, and inhibiting proliferation and adhesion in chronic myeloid leukemia cells. These results indicated that HMGB1 may be used as a potential therapeutic target, with cordycepin having potential as an auxiliary drug. Therefore, it is suggested that HMGB1 knockdown and corycepin treatement may present a promising therapeutic strategy for leukemia.


Assuntos
Antineoplásicos/farmacologia , Desoxiadenosinas/farmacologia , Proteína HMGB1/genética , Apoptose , Adesão Celular/efeitos dos fármacos , Proliferação de Células , Terapia Combinada , Ciclo-Oxigenase 2/metabolismo , Técnicas de Silenciamento de Genes , Células HEK293 , Proteína HMGB1/metabolismo , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo
6.
Int J Clin Exp Pathol ; 8(11): 15489-96, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26823919

RESUMO

WISP1, a Wnt-induced secreted protein, has been found to have anticancer activity. ALL is a leading cause of death. Here we investigate the WISP1 effects on ALL Jurkat cells. Cell viability was assessed by CCK-8. Cell cycle and apoptosis were detected by flow cytometry. Mitochondrial membrane potential (MMP) was monitored using TMRM. Generation of reactive oxygen species (ROS) was quantified using DCFH-DA. Western blot was used to detect the expression of cell proliferation and apoptosis related genes. The results showed that knockdown of WISP1 significantly inhibited proliferation of Jurkat cells. Parallelly, cell cycle distribution was increased at G1 phase and apoptotic rate was induced after WISP1 knockdown. Furthermore, knockdown of WISP1 induced apoptosis of Jurkat cells was also associated with loss of MMP and generation of ROS. Western blot results showed that the protein expression p-AKT, PCNA, CDK1, P-ERK, CDK2, VEGF, VEGFR2 and Bcl2 were decreased, while the expression of Bax was up-regulated. In conclusion, WISP1 plays an important role in proliferation and apoptosis of Jurkat cells in mitochondria dependent pathway, the specific mechanisms need further study.


Assuntos
Apoptose , Proteínas de Sinalização Intercelular CCN/metabolismo , Proliferação de Células , Técnicas de Silenciamento de Genes , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Sinalização Intercelular CCN/genética , Proteínas de Ciclo Celular/metabolismo , Regulação para Baixo , Pontos de Checagem da Fase G1 do Ciclo Celular , Regulação Neoplásica da Expressão Gênica , Humanos , Células Jurkat , Células K562 , Potencial da Membrana Mitocondrial , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Proteínas Proto-Oncogênicas/genética , Interferência de RNA , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Fatores de Tempo , Transfecção , Células U937
7.
Clin Lab ; 59(7-8): 735-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24133900

RESUMO

BACKGROUND: The study was conducted in order to analyze the incidence of heparin-induced thrombocytopenia (HIT) and heparin-induced thrombocytopenia and thrombosis syndrome (HITTS) in 240 patients from the Department of Vascular Surgery in China, to evaluate the current laboratory detection technique, and to explore the feasibility for the technique to be developed in China. METHODS: 240 patients receiving unfractionated heparin (UFH) were studied in one center. Before and after the UFH treatment, platelet count, HIT-antibody ELISA test, and heparin-induced platelet aggregation (HIPA) were tested. RESULTS: Among 240 patients, HIT was diagnosed in 36 cases. The incidence was 15%. HITTS occurred in 6 cases (2.5%). The median time of thrombocytopenia was the 8th day. Platelet counts recovered to normal level in 3 - 6 days after heparin withdrawal CONCLUSIONS: The incidence of HIT is higher; however, the incidence of HITTS is lower. Monitoring platelet count, which is simple and easy to do and available in hospitals at different levels (township hospital included), is a reliable method to diagnose HIT early. The HIT-antibody ELISA test could be introduced in specific hospitals to prescreen HIT. In view of the higher sensitivity and specificity of HIPA, it can be used in larger diagnostic centers in all the big cities of China.


Assuntos
Heparina/efeitos adversos , Trombocitopenia/induzido quimicamente , Adulto , Idoso , China , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ativação Plaquetária
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