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1.
Elife ; 122024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488852

RESUMO

Dysregulated pre-mRNA splicing and metabolism are two hallmarks of MYC-driven cancers. Pharmacological inhibition of both processes has been extensively investigated as potential therapeutic avenues in preclinical and clinical studies. However, how pre-mRNA splicing and metabolism are orchestrated in response to oncogenic stress and therapies is poorly understood. Here, we demonstrate that jumonji domain containing 6, arginine demethylase, and lysine hydroxylase, JMJD6, acts as a hub connecting splicing and metabolism in MYC-driven human neuroblastoma. JMJD6 cooperates with MYC in cellular transformation of murine neural crest cells by physically interacting with RNA binding proteins involved in pre-mRNA splicing and protein homeostasis. Notably, JMJD6 controls the alternative splicing of two isoforms of glutaminase (GLS), namely kidney-type glutaminase (KGA) and glutaminase C (GAC), which are rate-limiting enzymes of glutaminolysis in the central carbon metabolism in neuroblastoma. Further, we show that JMJD6 is correlated with the anti-cancer activity of indisulam, a 'molecular glue' that degrades splicing factor RBM39, which complexes with JMJD6. The indisulam-mediated cancer cell killing is at least partly dependent on the glutamine-related metabolic pathway mediated by JMJD6. Our findings reveal a cancer-promoting metabolic program is associated with alternative pre-mRNA splicing through JMJD6, providing a rationale to target JMJD6 as a therapeutic avenue for treating MYC-driven cancers.


Assuntos
Neuroblastoma , Precursores de RNA , Sulfonamidas , Humanos , Animais , Camundongos , Precursores de RNA/genética , Precursores de RNA/metabolismo , Glutaminase/genética , Reprogramação Metabólica , Histona Desmetilases com o Domínio Jumonji/metabolismo
2.
bioRxiv ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37425900

RESUMO

Dysregulated pre-mRNA splicing and metabolism are two hallmarks of MYC-driven cancers. Pharmacological inhibition of both processes has been extensively investigated as potential therapeutic avenues in preclinical and clinical studies. However, how pre-mRNA splicing and metabolism are orchestrated in response to oncogenic stress and therapies is poorly understood. Here, we demonstrate that Jumonji Domain Containing 6, Arginine Demethylase and Lysine Hydroxylase, JMJD6, acts as a hub connecting splicing and metabolism in MYC-driven neuroblastoma. JMJD6 cooperates with MYC in cellular transformation by physically interacting with RNA binding proteins involved in pre-mRNA splicing and protein homeostasis. Notably, JMJD6 controls the alternative splicing of two isoforms of glutaminase (GLS), namely kidney-type glutaminase (KGA) and glutaminase C (GAC), which are rate-limiting enzymes of glutaminolysis in the central carbon metabolism in neuroblastoma. Further, we show that JMJD6 is correlated with the anti-cancer activity of indisulam, a "molecular glue" that degrades splicing factor RBM39, which complexes with JMJD6. The indisulam-mediated cancer cell killing is at least partly dependent on the glutamine-related metabolic pathway mediated by JMJD6. Our findings reveal a cancer-promoting metabolic program is associated with alternative pre-mRNA splicing through JMJD6, providing a rationale to target JMJD6 as a therapeutic avenue for treating MYC-driven cancers.

3.
IEEE Trans Med Imaging ; 42(10): 3069-3079, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37167043

RESUMO

Clarifying the morphological characteristics of neurons can promote the understanding of brain function. However, traditional morphometrics fail to capture the modeling of each point in reconstructed neurons, leading to limited ability to distinguish massive nerve fibers and restricted application scenarios. To address these challenges, we propose MorphoGNN, a single neuron morphological embedding based on a graph neural network in this study. MorphoGNN learns the point-level structure information of reconstructed nerve fibers by considering their nearest neighbors on each hidden layer. This enables MorphoGNN to capture the lower-dimensional representation of a single neuron through an end-to-end model. In order to meet the requirements of various tasks, both supervised and self-supervised training strategies are designed to learn the characteristics that fit artificial semantics or the morphological patterns of neurons, respectively. We quantitatively compare our embeddings with other features in neuron classification and retrieval tasks and demonstrate cutting-edge performance. Additionally, we introduce our embeddings to the task of reconstruction quality classification and neuron clustering, where they can help detect reconstruction errors and obtain similar subtyping results to existing work. Furthermore, our method can be handily combined with other modal features, such as microscopic image features and traditional morphometrics. Ablation and robustness tests are also conducted to analyze the impact of several network components and low-quality reconstructed neurons on the performance of our method. The code is available at https://github.com/fun0515/MorphoGNN.


Assuntos
Fibras Nervosas , Neurônios , Análise por Conglomerados , Redes Neurais de Computação , Percepção
4.
Nanotechnology ; 34(7)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36332230

RESUMO

Hierarchical domain structures associated with oxygen octahedra tilting patterns were observed in lead-free (Bi1/2Na1/2)TiO3ceramics using aberration-corrected high-resolution transmission electron microscopy (HRTEM). Three types of domains are induced by distinct mechanisms: the 'orientation-domain' is induced at micrometer scale formed by different tilting orientations of the oxygen octahedra, the 'meso-chemical-domain' occurs at a few tens of nanometer scale by chemical composition variation on the A-site in the ABO3perovskite structure, and the 'nano-cluster-region' runs across several unit-cells with apparent A-site cation segregation with oxygen vacancies clustering around Na cations. Based on HRTEM amplitude contrast imaging (ACI), the correlation between the oxygen octahedral tilting pattern and compositional non-stoichiometry was established. The role of the hierarchical domain structure associated with the tilting patterns of the oxygen octahedra on the ferroelectric behavior of (Bi1/2Na1/2)TiO3is also discussed.

5.
Cancers (Basel) ; 14(7)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35406427

RESUMO

Increased TERT mRNA is associated with disease relapse in favorable histology Wilms tumor (WT). This study sought to understand the mechanism of increased TERT expression by determining the association between TERT and WT1 and N-MYC, two proteins important in Wilms tumor pathogenesis that have been shown to regulate TERT expression. Three out of 45 (6.7%) WTs and the corresponding patient-derived xenografts harbored canonical gain-of-function mutations in the TERT promoter. This study identified near ubiquitous hypermethylation of the TERT promoter region in WT compared to normal kidney. WTs with biallelic inactivating mutations in WT1 (7/45, 15.6%) were found to have lower TERT expression by RNA-seq and qRT-PCR and lower telomerase activity determined by the telomerase repeat amplification protocol. Anaplastic histology and increased percentage of blastema were positively correlated with higher TERT expression and telomerase activity. In vitro shRNA knockdown of WT1 resulted in decreased expression of TERT, reduced colony formation, and decreased proliferation of WiT49, an anaplastic WT cell line with wild-type WT1. CRISPR-Cas9-mediated knockout of WT1 resulted in decreased expression of telomere-related gene pathways. However, an inducible Wt1-knockout mouse model showed no relationship between Wt1 knockout and Tert expression in normal murine nephrogenesis, suggesting that WT1 and TERT are coupled in transformed cells but not in normal kidney tissues. N-MYC overexpression resulted in increased TERT promoter activity and TERT transcription. Thus, multiple mechanisms of TERT activation are involved in WT and are associated with anaplastic histology and increased blastema. This study is novel because it identifies potential mechanisms of TERT activation in Wilms tumor that could be of therapeutic interests.

6.
Nat Commun ; 12(1): 7204, 2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34893606

RESUMO

The H3K27me2/me3 histone demethylase KDM6B is essential to neuroblastoma cell survival. However, the mechanism of KDM6B action remains poorly defined. We demonstrate that inhibition of KDM6B activity 1) reduces the chromatin accessibility of E2F target genes and MYCN, 2) selectively leads to an increase of H3K27me3 but a decrease of the enhancer mark H3K4me1 at the CTCF and BORIS binding sites, which may, consequently, disrupt the long-range chromatin interaction of MYCN and E2F target genes, and 3) phenocopies the transcriptome induced by the specific CDK4/6 inhibitor palbociclib. Overexpression of CDK4/6 or Rb1 knockout confers neuroblastoma cell resistance to both palbociclib and the KDM6 inhibitor GSK-J4. These data indicate that KDM6B promotes an oncogenic CDK4/6-pRB-E2F pathway in neuroblastoma cells via H3K27me3-dependent enhancer-promoter interactions, providing a rationale to target KDM6B for high-risk neuroblastoma.


Assuntos
Quinase 4 Dependente de Ciclina/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/genética , Neuroblastoma/metabolismo , Oncogenes/genética , Linhagem Celular Tumoral , Quinase 4 Dependente de Ciclina/genética , Epigenômica , Regulação Neoplásica da Expressão Gênica , Histona Desmetilases/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Proteína Proto-Oncogênica N-Myc/genética , Fatores de Transcrição
7.
J Pharm Biomed Anal ; 200: 114077, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33892396

RESUMO

Drug resistance and adverse reactions to oxaliplatin remain a considerable issue in clinical practice. Emerging evidence has suggested that alterations in the lipid metabolism during drug therapy affect cancer cells. To gain insight into the important process of lipid metabolism, we investigated the lipid and gene expression profile changes in HT29 cells treated with oxaliplatin. A total of 1403 lipid species from 16 lipid classes were identified by UHPLC-MS. Interestingly, phospholipids, including phosphatidylglycerol (PG), phosphatidic acid (PA), phosphatidylcholine (PC), and most of phosphatidylethanolamine (PE) with polyunsaturated fatty acid (PUFA) chains, were significantly higher due to oxaliplatin treatment, while triacylglycerols (TAGs) with a saturated fatty acid chain or monounsaturated fatty acid were significantly downregulated. Gene Set Enrichment Analysis (GSEA) based on RNA sequencing data suggested that neutral lipid metabolism was enriched in the control group, whereas the phospholipid metabolic process was enriched in the oxaliplatin-treated group. We observed that altered lipid metabolism enzyme genes were involved in the synthesis and lipolysis of TAGs and the Lands cycle pathway based on the network between the core lipid-related gene and lipid species, which was further verified by qRT-PCR. In summary, our findings revealed that oxaliplatin impressed a specific lipid profile signature and lipid transcriptional reprogramming in HT29 cells, which provides new insights into biomarker discovery and pathways for overcoming drug resistance and adverse reactions.


Assuntos
Neoplasias Colorretais , Lipidômica , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Humanos , Metabolismo dos Lipídeos/genética , Oxaliplatina , Fosfolipídeos , Transcriptoma
8.
Medicine (Baltimore) ; 98(28): e16115, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31305395

RESUMO

INTRODUCTION: The benefits of magnesium sulfate for surgical field during endoscopic sinus surgery remain controversial. We conduct a systematic review and meta-analysis to explore the influence of magnesium sulfate versus placebo on surgical field during endoscopic sinus surgery. METHODS: We search PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through November 2018 for randomized controlled trials (RCTs) assessing the effect of magnesium sulfate versus placebo on surgical field during endoscopic sinus surgery. This meta-analysis is performed using the random-effect model. RESULTS: Four RCTs and 404 patients are included in the meta-analysis. Overall, compared with control group endoscopic sinus surgery, magnesium sulfate has remarkably positive impact on surgical field scores (MD = -1.76; 95% CI = -2.33 to -1.18; P < .00001), and intraoperative blood loss (MD = -89.09; 95% CI = -163.20 to -14.97; P = .02), but shows no markedly effect on surgery duration (MD = -7.08; 95% CI = -21.38 to 7.22; P = .33), fentanyl (MD = -0.64; 95% CI = -1.97 to 0.70; P = .35), and vecuronium (MD = -3.64; 95% CI = -10.99 to 3.70; P = .33). CONCLUSIONS: Magnesium sulfate exerts positive impact on surgical field and blood loss reduction for endoscopic sinus surgery.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Sulfato de Magnésio/uso terapêutico , Cirurgia Endoscópica por Orifício Natural , Vasodilatadores/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Dis Markers ; 2019: 2829798, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191746

RESUMO

The molecular mechanism for colorectal cancer to develop remains unelucidated. To find biomarkers related to colorectal cancer development, we analyzed the gene expression profile of 380 colorectal cancer patients and 51 healthy controls by R software. Finally, 1579 upregulated differential expression genes (DEGs) and 3218 downregulated DEGs were identified. Then, the top 20 upregulated DEGs were compared with 181 upregulated DEGs that we reported previously, and 11 overlapped DEGs were found. NFE2L3 (nuclear factor, erythroid 2-like 3) was among those overlapped DEGs and was rarely reported in colorectal cancer. Real-time polymerase chain reaction (PCR) results showed that higher NFE2L3 expression levels were identified in paired tumor samples than in paratumor samples (48 paired samples). Flow cytometry analysis revealed that the cell cycle was arrested at the G0/G1 phase after inhibition of NFE2L3 in both HCT116 and SW480 cell lines. Western blot detection showed that CCND1 and phosphorylated Rb transcriptional corepressor 1 at ser-807/811 (pRb1-ser807/811) expression levels were downregulated when NFE2L3 was inhibited in those two cell lines. A significant positive correlation was observed between NFE2L3 and CCND1 expression levels in colorectal tissue samples. These evidences indicate that downregulation of NFE2L3 induces cell cycle arrest at the G0/G1 phase through downregulation of CCND1 and pRb1-ser807/811.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Neoplasias Colorretais/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Ciclina D1/genética , Ciclina D1/metabolismo , Regulação para Baixo , Células HCT116 , Humanos , Proteínas Salivares Ricas em Prolina/genética , Proteínas Salivares Ricas em Prolina/metabolismo
10.
Mol Med Rep ; 19(3): 1509-1520, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30628683

RESUMO

(­)­Epigallocatechin­3­gallate (EGCG), a major constituent of green tea, is a potential anticancer agent, but the molecular mechanisms of its effects are not well­understood. The present study was conducted to examine the mechanism of EGCG in lung cancer cells. Alterations in long non­coding RNAs (lncRNAs) and mRNAs were investigated in lung cancer cells treated with EGCG by lncRNA microarray analysis. Furthermore, the functions and signaling pathways regulated by EGCG were predicted by bioinformatics analysis. A total of 960 lncRNAs and 1,434 mRNAs were significantly altered following EGCG treatment. These lncRNAs were distributed across nearly all human chromosomes and the mRNAs were involved in the cell cycle and the mitotic cell cycle process. Through a combination of microarray and bioinformatics analysis, 20 mRNAs predicted to serve a key role in the EGCG regulation were identified, and certain regulatory networks involving EGCG­regulated lncRNAs were predicted. In conclusion, EGCG affects the expression of various lncRNAs and mRNAs in the cells, therefore affecting cell functions. The results of the present study provide an insight into the mechanism of EGCG, which may be useful for therapeutic development.


Assuntos
Catequina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Catequina/farmacologia , Linhagem Celular Tumoral , Biologia Computacional , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Transdução de Sinais/efeitos dos fármacos
11.
iScience ; 9: 84-100, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30388705

RESUMO

The p53 tumor suppressor pathway is frequently inactivated in human cancers. However, there are some cancer types without commonly recognized alterations in p53 signaling. Here we report that histone demethylase KDM5A is involved in the regulation of p53 activity. KDM5A is significantly amplified in multiple types of cancers, an event that tends to be mutually exclusive to p53 mutation. We show that KDM5A acts as a negative regulator of p53 signaling through inhibition of p53 translation via suppression of a subgroup of eukaryotic translation initiation genes. Genetic deletion of KDM5A results in upregulation of p53 in multiple lineages of cancer cells and inhibits tumor growth in a p53-dependent manner. In addition, we have identified a regulatory loop between p53, miR-34, and KDM5A, whereby the induction of miR-34 leads to suppression of KDM5A. Thus, our findings reveal a mechanism by which KDM5A inhibits p53 translation to modulate cancer progression.

12.
Int J Biol Sci ; 14(13): 1859-1872, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30443189

RESUMO

Platinum-based chemotherapy is used as first-line therapy for advanced non-small-cell lung cancer (NSCLC). However, there is no effective indicator to predict whether the patient would be chemo-resistant or sensitive to the therapy. In addition, it is urgent to elucidate the mechanisms of cisplatin resistance. RIF1 plays important roles in DNA replication regulation and DNA repair pathway. However, the role of RIF1 in NSCLC progression and chemotherapy response is still unknown. In this study, we found that RIF1 expression was correlated with the response of NSCLC patients to platinum-based chemotherapy (n=89, P=0.002). Among patients who have been treated with platinum chemo-therapy, those with high levels of RIF1 expression had significantly shorter survival than those with low RIF1 expression (P<0.05). RIF1 knockdown increased sensitivity to cisplatin in NSCLC patients both in vitro and in vivo. Moreover, RIF1 knockdown induced G0/G1 phase arrest and increased cisplatin-induced apoptosis and DNA damage. Further investigation showed that RIF1 regulated the expression of MYC and MYC downstream targets, including the cell cycle and double-stranded break (DSB) repair genes which might mediate the effect of RIF1 on cellular response to cisplatin. Overexpression of MYC could reverse the inhibition of MYC targets by RIF1 knockdown. Taken together, these data revealed that RIF1 played an important role in regulating MYC and MYC-activated genes, which in turn contributes to cellular response to cisplatin and NSCLC patients' response to platinum-based chemotherapy. RIF1 might serve as a novel biomarker for predicting platinum-based chemo-sensitivity and the prognosis of NSCLC patients, so as to guide the chemotherapy regimen adjustment for individual patient with NSCLC and improve their clinical outcomes.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Platina/farmacologia , Platina/uso terapêutico , Proteínas de Ligação a Telômeros/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/genética , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Nus , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Proteínas de Ligação a Telômeros/genética
13.
J Exp Clin Cancer Res ; 37(1): 182, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-30075819

RESUMO

BACKGROUND: Human telomerase reverse transcriptase (hTERT) is highly expressed in over 80% of tumors, including human epithelial ovarian cancer (EOC). However, the mechanisms through which hTERT is up-regulated in EOC and promotes tumor progression remain unclear. The aim of this study is to identify RIF1 as a novel molecular target that modulate hTERT signaling and EOC growth. METHODS: RIF1 expression in ovarian cancer, benign and normal ovarian tissues was examined by immunohistochemistry. The biological role of RIF1 was revealed by MTS, colony formation and sphere formation assays. Luciferase reporter assay and chromatin immunoprecipitation (CHIP) assay were used to verify RIF1 as a novel hTERT promoter-binding protein in EOC cells. The role of RIF1 on tumorigenesis in vivo was detected by the xenograft model. RESULTS: RIF1 expression is upregulated in EOC tissues and is closely correlated with FIGO stage and prognosis of EOC patients. Functionally, RIF1 knockdown suppressed the expression and promoter activity of hTERT and consequently inhibited the growth and CSC-like traits of EOC cells. RIF1 knockdown also inhibited tumorigenesis in xenograft model. RIF1 overexpression had the opposite effect. Luciferase reporter assay and ChIP assay verified RIF1 directly bound to hTERT promoter to upregulate its expression. The rescue experiments suggested hTERT overexpression rescued the inhibition of EOC cell growth and CSC-like traits mediated by RIF1 knockdown. Consistently, hTERT knockdown abrogated the RIF1-induced promotion of EOC cell growth and CSC-like traits. CONCLUSIONS: RIF1 promotes EOC progression by activating hTERT and the RIF1/hTERT pathway may be a potential therapeutic target for EOC patients.


Assuntos
Carcinoma Epitelial do Ovário/metabolismo , Neoplasias Ovarianas/metabolismo , Telomerase/biossíntese , Proteínas de Ligação a Telômeros/metabolismo , Animais , Carcinoma Epitelial do Ovário/enzimologia , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/patologia , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Ovarianas/enzimologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Telomerase/genética , Telomerase/metabolismo , Proteínas de Ligação a Telômeros/biossíntese , Proteínas de Ligação a Telômeros/genética , Transfecção
14.
Front Chem ; 6: 78, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29755966

RESUMO

Highly porous carbon with large surface areas is prepared using cotton as carbon sources which derived from discard cotton balls. Subsequently, the sulfur-nitrogen co-doped carbon was obtained by heat treatment the carbon in presence of thiourea and evaluated as Lithium-ion batteries anode. Benefiting from the S, N co-doping, the obtained S, N co-doped carbon exhibits excellent electrochemical performance. As a result, the as-prepared S, N co-doped carbon can deliver a high reversible capacity of 1,101.1 mA h g-1 after 150 cycles at 0.2 A g-1, and a high capacity of 531.2 mA h g-1 can be observed even after 5,000 cycles at 10.0 A g-1. Moreover, excellently rate capability also can be observed, a high capacity of 689 mA h g-1 can be obtained at 5.0 A g-1. This superior lithium storage performance of S, N co-doped carbon make it as a promising low-cost and sustainable anode for high performance lithium ion batteries.

15.
Sci Total Environ ; 631-632: 308-316, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29525710

RESUMO

Industrial sludge has been shown to be a valuable source of transition metals and to be effective in NO reduction. This research has further revealed a characteristic texture (O-Me-C) that promotes effective NO reduction and supports its existence in a sludge-derived catalyst. HRTEM exhibited that the O-Me-C consisted of multi-metal-oxide core, carbon shell and their binding interfaces. Furthermore, pre-treatment of the sludge with aromatic containing wastewater produced a more active texture (O-Me-GOL), characterized by the presence of multi-metal-oxide core, graphene oxide-like carbon and highly active interfaces (EELS, Mössbauer and Raman). As a result, the hybrid with O-Me-GOL exhibited enhanced activity and was able to remove >45% of NO (1000 ppm) at 200 °C and >99% at 400 °C over a much longer period (from 25 to 180 min) with an hourly gas space velocity of 14,400 h-1. Besides, the hybrid showed excellent resistance to both SO2 and O2. Therefore, the present work promoted the high value-added utilization of environment waste, and produced efficient catalyst in favor of sustainable development.

16.
ACS Appl Mater Interfaces ; 10(6): 5978-5983, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29345457

RESUMO

The garnet ionic conductor is one of the promising candidate electrolytes for all-solid-state secondary lithium batteries, thanks to its high lithium ion conductivity and good thermal and chemical stability. However, its microstructure is difficult to approach because it is very sensitive to the inquisitive electron beam. In this study based on a scanning electron microscope (SEM), we found that the electron beam expulses the lithium out of Li6.4La3Zr1.4Ta0.6O12 (LLZTO), and the expulsed zone expands to where a stationary beam could extend and penetrate. The expulsion of metallic lithium was confirmed by its oxidation reaction after nitrogen inflow into the SEM. This phenomenon may provide us an effective probe to peer into the conductive nature of this electrolyte. A frame-scan scheme is employed to measure the expulsion rate by controllable and more uniform incidence of electrons. Lithium accumulation processes are continuously recorded and classified into four modes by fitting its growth behaviors into a dynamic equation that is mainly related to the initial ion concentration and ion migration rate in the electrolyte. These results open a novel possibility of using the SEM probe to gain dynamic information on ion migration and lithium metal growth in solid materials.

17.
Dalton Trans ; 46(39): 13446-13455, 2017 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-28949355

RESUMO

The compounds MNi21B20 (M = In, Sn) have been synthesized and their cubic crystal structure determined (space group Pm3[combining macron]m, lattice parameters a = 7.1730(1) Å and a = 7.1834(1) Å, respectively). The structure can be described as a hierarchical partitioning of space based on a reo-e net formed by Ni3 species with large cubical, cuboctahedral and rhombicuboctahedral voids being filled according to [Ni1@Ni38], [M@Ni312], and [Ni26@B20@Ni324], respectively. The [Ni6@B20] motif inside the rhombicuboctahedral voids features an empty [Ni6] octahedron surrounded by a [B20] cage recently described in E2Ni21B20 (E = Zn, Ga). Position-space bonding analysis using ELI-D and QTAIM space partitioning as well as 2- and 3-center delocalization indices gives strong support to an alternative chemical description of space partitioning based on face-condensed [B@Ni6] trigonal prisms as basic building blocks. The shortest B-B contacts display locally nested 3-center B-B-Ni bonding inside each trigonal prism. This clearly rules out the notion of [Ni6@B20] clusters and leads to the arrangement of 20 face-condensed [B@Ni23Ni33] trigonal prisms resulting in a triple-shell like situation Ni26@B20@Ni324(reo-e), where the shells display comparable intra- and inter-shell bonding. Both compounds are Pauli paramagnets displaying metallic conductivity.

18.
Cancer Res ; 77(17): 4626-4638, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28684529

RESUMO

Histone lysine demethylases facilitate the activity of oncogenic transcription factors, including possibly MYC. Here we show that multiple histone demethylases influence the viability and poor prognosis of neuroblastoma cells, where MYC is often overexpressed. We also identified the approved small-molecule antifungal agent ciclopirox as a novel pan-histone demethylase inhibitor. Ciclopirox targeted several histone demethylases, including KDM4B implicated in MYC function. Accordingly, ciclopirox inhibited Myc signaling in parallel with mitochondrial oxidative phosphorylation, resulting in suppression of neuroblastoma cell viability and inhibition of tumor growth associated with an induction of differentiation. Our findings provide new insights into epigenetic regulation of MYC function and suggest a novel pharmacologic basis to target histone demethylases as an indirect MYC-targeting approach for cancer therapy. Cancer Res; 77(17); 4626-38. ©2017 AACR.


Assuntos
Antifúngicos/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Histona Desmetilases/antagonistas & inibidores , Neuroblastoma/tratamento farmacológico , Proteínas Proto-Oncogênicas c-myc/metabolismo , Piridonas/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclopirox , Epigênese Genética , Histonas/metabolismo , Humanos , Camundongos , Camundongos SCID , Neuroblastoma/enzimologia , Neuroblastoma/patologia , Fosforilação Oxidativa/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/genética , RNA Interferente Pequeno/genética , Transcrição Gênica/efeitos dos fármacos , Células Tumorais Cultivadas
19.
Oncotarget ; 8(63): 106962-106975, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29291003

RESUMO

Diffuse gliomas is a kind of common malignant primary brain tumor. Pseudogenes have multilayered biological function in the progression of human cancers. In this study, Differentially Expressed Pseudogenes (DEPs) between glioblastomas and non-tumor controls were found by bioinformatics analysis, of which the annexin A2 pseudogenes (ANXA2P1, ANXA2P2 and ANXA2P3) were significantly up-regulated, along with the parent gene annexin A2 (ANXA2). Among four glioblastoma subtypes, ANXA2P1 and ANXA2P2 were preferentially expressed in mesenchymal subtype and less expressed in proneural subtype. Meanwhile, Pearson's correlation analysis revealed that the expression level of ANXA2 was positively correlated with ANXA2 pseudogenes expression. Then, the expression patterns of ANXA2 and its pseudogenes were validated in diffuse glioma specimens (n=99) and non-tumor tissues (n=12) by quantitative real-time PCR (qRT-PCR). Additionally, Kaplan-Meier analysis revealed that highly expressed ANXA2 and annexin A2 pseudogenes were associated with the poor survival outcome of glioma patients. Cox regression analyses suggested that ANXA2, ANXA2P1 and ANXA2P2 were the independent prognosis factors for gliomas. Furthermore, down-regulation of ANXA2 and ANXA2 pseudogenes might contribute to the improvement of patients' survival who received chemotherapy and radiotherapy. These results demonstrated that ANXA2 pseudogenes and ANXA2 could be used as the novel biomarkers for diagnosis, prognosis and target therapy of gliomas.

20.
Chin Med ; 11: 11, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27006687

RESUMO

BACKGROUND: Sodium tanshinone IIA sulfonate (STS) is a water-soluble derivative of tanshinone IIA for treating cardiovascular disorders. The roles of cytochrome P450 enzymes (CYPs) in the metabolism of STS have remained unclear. This study aims to screen the main CYPs for metabolism of STS and study their interactions in vitro. METHODS: Seven major CYPs were screened for metabolism of STS by human liver microsomes (HLMs) or recombinant CYP isoforms. Phenacetin (CYP1A2), coumarin (CYP2A6), tolbutamide (CYP2C9), metoprolol (CYP2D6), chlorzoxazone (CYP2E1), S-mephenytoin (CYP2C19), and midazolam (CYP3A4) were used as probe substrates to determine the potential of STS in affecting CYP-mediated phase I metabolism in humans. Enzyme kinetic studies were performed to investigate the modes of inhibition of the enzyme-substrate interactions by GraphPad Prism Enzyme Kinetic 5 Demo software. RESULTS: Sodium tanshinone IIA sulfonate inhibited the activity of CYP3A4 in a dose-dependent manner by the HLMs and CYP3A4 isoform. The K m and V max values of STS were 54.8 ± 14.6 µM and 0.9 ± 0.1 nmol/mg protein/min, respectively, for the HLMs and 7.5 ± 1.4 µM and 6.8 ± 0.3 nmol/nmol P450/min, respectively, for CYP3A4. CYP1A2, CYP2A6, CYP2C9, CYP2D6, CYP2E1, and CYP2C19 showed minimal or no effects on the metabolism of STS. CONCLUSION: This in vitro study showed that STS mainly inhibited the activities of CYP3A4.

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