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1.
BMC Cancer ; 24(1): 194, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347489

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the most common type of malignant liver tumor with poor prognosis. In this study, we investigated the expression of transforming growth factor beta regulator 4 (TBRG4) in HCC and its effects on the proliferation, invasion, and metastasis of HCC cells, and analyzed the possible molecular mechanisms. METHOD: Downloading the expression and clinical information of HCC samples in the TCGA database, analyzing the expression differences of TBRG4 by bioinformatics methods, analyzing the clinical relevance and prognostic significance. Performing GO, KEGG and GSEA enrichment analysis on the TBRG4-related gene set in patient HCC tissues. Applying cell counting, scratch test and Transwell experiment to study the biological function of TBRG4 in HCC. Mitochondrial membrane potential, apoptosis and ROS levels were evaluated to assess cell iron death. Western blot, RT-PCR, laser confocal microscopy and co-immunoprecipitation were used to detect and analyze the downstream signaling pathways and interacting molecules of TBRG4. RESULTS: Bioinformatics analysis revealed that TBRG4 was abnormally highly expressed in HCC tumor tissues and was associated with poor prognosis and metastasis in HCC patients. GO and KEGG functional enrichment analysis showed that TBRG4 was related to oxidative stress and NADH dehydrogenase (ubiquinone) activity. GSEA enrichment analysis showed that TBRG4 was associated with Beta catenin independent wnt signaling and B cell receptor. Functional experiments confirmed that knocking down TBRG4 could inhibit the proliferation, migration, and invasion of HCC cells. Mechanistically, TBRG4 inhibited the function of HCC cells through the DDX56/p-AKT/GSK3ß signaling pathway. In addition, interference with TBRG4 expression could reduce the mitochondrial membrane potential and accumulate ROS in HCC cells, leading to increased ferroptosis. Co-IP analysis showed that TBRG4 specifically bound to Beclin1. CONCLUSION: TBRG4 is highly expressed in HCC tumor tissues and is associated with poor prognosis. It may regulate the proliferation, invasion, and metastasis of HCC cells through the DDX56/p-AKT/GSK3ß signaling pathway. TBRG4 may interact with Beclin1 to regulate the ferroptosis of HCC cells.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , Humanos , Proteína Beclina-1/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , RNA Helicases DEAD-box/genética , Ferroptose/genética , Regulação Neoplásica da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/metabolismo , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Via de Sinalização Wnt
2.
Foodborne Pathog Dis ; 21(2): 109-118, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38011665

RESUMO

Pork products were the most common media of Salmonella in China, breaded pork products as a very popular meat presently, whose Salmonella risk should be drawn to attention. Given that quantitative risk assessment is a more scientific method for risk evaluation, a quantitative risk assessment model of Salmonella in breaded pork products was first constructed from processing to consumption, and was used for assessing the risk and the effective interventions in this study. The data of Salmonella contamination in breaded pork products during processing were obtained from the actual detection data of samples from a representative meat processing plant. With combining the predictive microbial modeling and dose-response relationship, the risk of Salmonella in breaded pork products was charactered, and the probability of Salmonella infection per meal was found to be 5.585 × 10-9. Based on the results of sensitivity analysis, the curing and seasoning process was found to be the key control point for Salmonella contamination during the processing, and consumer behavior was the key control point affecting the probability of Salmonella infection from processing to consumption. The model was also applied for assessing the effectiveness of risk interventions, and among the nine interventions given, control of thawing temperature before cooking such as microwave thawing could reduce the risk of infection by 30.969-fold, while cooking the products thoroughly, Salmonella would not pose a pathogenic hazard to consumers. The model and the assessed results in this study may provide guidance on microbial control in producing process and safety consumption of breaded pork products.


Assuntos
Produtos da Carne , Carne Vermelha , Infecções por Salmonella , Animais , Suínos , Carne Vermelha/análise , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Manipulação de Alimentos/métodos , Salmonella , Medição de Risco/métodos
3.
J Med Virol ; 95(1): e28327, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36415105

RESUMO

Quinolin-2-one represents an important and valuable chemical motif that possesses a wide variety of biological activities; however, the anti-influenza activities of quinolin-2-one-containing compounds were rarely reported. Herein, we describe the screening and identification of 3-aryl-quinolin-2-one derivatives as a novel class of antiviral agents. The 3-aryl-quinolinone derivatives were synthesized via an efficient copper-catalyzed reaction cascade that we previously developed. Using this synthetic method, preliminary structure-activity relationships of this scaffold against the influenza A virus infection were systematically explored. The most potent compound 34 displayed IC50 values of 2.14 and 4.88 µM against the replication of H3N2 (A/HK/8/68) and H1N1 (A/WSN/33) strains, respectively, without apparent cytotoxicity on MDCK cells. We further demonstrated that 27 and 34 potently inhibited the plaque formation of the IAV, rendering this scaffold attractive for pursuing novel anti-influenza agents.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A , Influenza Humana , Animais , Cães , Humanos , Antivirais/uso terapêutico , Vírus da Influenza A Subtipo H3N2 , Influenza Humana/tratamento farmacológico , Células Madin Darby de Rim Canino
4.
Ecotoxicol Environ Saf ; 259: 115060, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37229876

RESUMO

Bisphenol A (BPA) has a number of adverse effects on the reproductive development of females. In particular, the mechanism of disruption of ovarian development in adolescent mice is still unclear. Based on transcriptome sequencing results, a differentially expressed lncRNA, Fhad1os2, was detected in the ovaries of BPA-exposed pubertal mice. In our study, the lncRNA Fhad1os2, localized in the ovarian granulosa cell cytoplasm, could regulate the proliferation of mouse ovarian granulosa cells. Mechanistically, the results of RNA pull-down experiments as well as mass spectrometry analysis showed that ERα, an interfering signaling molecule of BPA, could directly bind lncRNA Fhad1os2 and decrease the transcription of lncRNA Fhad1os2 in response to the estrogen-like effect of BPA. BPA exposure also caused abnormal lncRNA Fhad1os2 pulldown protein-related signaling pathways in the ovaries of adolescent mice. Furthermore, lncRNA Fhad1os2 interacted with RUNX3, a transcription factor related to follicle development and hormone synthesis. As a negative regulator, lncRNA Fhad1os2 transactivated the expression of Runx3, which in turn induced RUNX3 to positively regulate aromatase (Cyp19a1) expression in mouse ovarian granulosa cells and promote estrogen synthesis. In conclusion, our study indicates that BPA exposure interferes with ERα-regulated lncRNA Fhad1os2 interactions with RUNX3 in pubertal mice, affecting estrogen synthesis in mouse granulosa cells and contributing to premature ovarian maturation in pubertal mice.


Assuntos
Ovário , RNA Longo não Codificante , Feminino , Camundongos , Animais , Receptor alfa de Estrogênio/metabolismo , RNA Longo não Codificante/metabolismo , Células da Granulosa , Compostos Benzidrílicos/metabolismo , Estrogênios/metabolismo
5.
Molecules ; 27(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36431773

RESUMO

To better guide microbial risk management and control, growth kinetic models of Salmonella with the coexistence of two other dominant background bacteria in pork were constructed. Sterilized pork cutlets were inoculated with a cocktail of Salmonella Derby (S. Derby), Pseudomonas aeruginosa (P. aeruginosa), and Escherichia coli (E. coli), and incubated at various temperatures (4-37 °C). The predictive growth models were developed based on the observed growth data. By comparing R2 of primary models, Baranyi models were preferred to fit the growth curves of S. Derby and P. aeruginosa, while the Huang model was preferred for E. coli (all R2 ≥ 0.997). The secondary Ratkowsky square root model can well describe the relationship between temperature and µmax (all R2 ≥ 0.97) or Lag (all R2 ≥ 0.98). Growth models were validated by the actual test values, with Bf and Af close to 1, and MSE around 0.001. The time for S. Derby to reach a pathogenic dose (105 CFU/g) at each temperature in pork was predicted accordingly and found to be earlier than the time when the pork began to be judged nearly fresh according to the sensory indicators. Therefore, the predictive microbiology model can be applied to more accurately predict the shelf life of pork to secure its quality and safety.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Suínos , Microbiologia de Alimentos , Carne Vermelha/microbiologia , Escherichia coli , Modelos Biológicos , Salmonella
6.
Diabetologia ; 64(5): 1144-1157, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33569632

RESUMO

AIMS/HYPOTHESIS: Failure of pancreatic and duodenal homeobox factor 1 (PDX1) to localise in the nucleus of islet beta cells under high-fat diet (HFD) conditions may be an early functional defect that contributes to beta cell failure in type 2 diabetes; however, the mechanism of PDX1 intracellular mislocalisation is unclear. Stress granules (SGs) are membrane-less cytoplasmic structures formed under stress that impair nucleocytoplasmic transport by sequestering nucleocytoplasmic transport factors and components of the nuclear pore complex. In this study, we investigated the stimulators that trigger SG formation in islet beta cells and the effects of SGs on PDX1 localisation and beta cell function. METHODS: The effect of palmitic acid (PA) on nucleocytoplasmic transport was investigated by using two reporters, S-tdTomato and S-GFP. SG assembly in rat insulinoma cell line INS1 cells, human islets under PA stress, and the pancreas of diet-induced obese mice was analysed using immunofluorescence and immunoblotting. SG protein components were identified through mass spectrometry. SG formation was blocked by specific inhibitors or genetic deletion of essential SG proteins, and then PDX1 localisation and beta cell function were investigated in vitro and in vivo. RESULTS: We showed that saturated fatty acids (SFAs) are endogenous stressors that disrupted nucleocytoplasmic transport and stimulated SG formation in pancreatic beta cells. Using mass spectrometry approaches, we revealed that several nucleocytoplasmic transport factors and PDX1 were localised to SGs after SFA treatment, which inhibited glucose-induced insulin secretion. Furthermore, we found that SFAs induced SG formation in a phosphoinositide 3-kinase (PI3K)/eukaryotic translation initiation factor 2α (EIF2α) dependent manner. Disruption of SG assembly by PI3K/EIF2α inhibitors or genetic deletion of T cell restricted intracellular antigen 1 (TIA1) in pancreatic beta cells effectively suppressed PA-induced PDX1 mislocalisation and ameliorated HFD-mediated beta cell dysfunction. CONCLUSIONS/INTERPRETATION: Our findings suggest a link between SG formation and beta cell dysfunction in the presence of SFAs. Preventing SG formation may be a potential therapeutic strategy for treating obesity and type 2 diabetes.


Assuntos
Ácidos Graxos/farmacologia , Proteínas de Homeodomínio/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Grânulos de Estresse/efeitos dos fármacos , Transativadores/metabolismo , Animais , Linhagem Celular , Dieta Hiperlipídica/efeitos adversos , Humanos , Células Secretoras de Insulina/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transporte Proteico/efeitos dos fármacos , Ratos , Grânulos de Estresse/metabolismo
7.
Ecotoxicol Environ Saf ; 225: 112739, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34481351

RESUMO

The incidence of metabolic diseases is increasing every year, and several studies have highlighted the activity of persistent organic pollutants (POPs) in causing hyperlipidemia and diabetes, and these compounds are considered to be endocrine disrupting chemicals (EDCs). Chlordane is classified as an endocrine disruptor, but the mechanism of how it functions is still unclear. This study investigates the effects of chlordane exposure on Drosophila larvae. Drosophila was cultured in diet containing 0.01 µM, 0.1 µM, 1 µM, 5 µM, and 10 µM chlordane, and the toxicity of chlordane, the growth and development of Drosophila, the homeostasis of glucose and lipid metabolism and insulin signaling pathway, lipid peroxidation-related indicators and Nrf2 signaling pathway were evaluated. We here found that exposure to high concentrations of chlordane decreased the survival rate of Drosophila and that exposure to low concentrations of chlordane caused disruption of glucose and lipid metabolism, increased insulin secretion and impairment of insulin signaling. Notably, it also led to massive ROS production and lipid peroxidation despite of the activation of Nrf2 signaling pathway, an important pathway for maintaining redox homeostasis. Collectively, chlordane causes lipid peroxidation and disrupts redox homeostasis, which may be a potential mechanism leading to impaired insulin signaling and the metabolism of glucose and lipid, ultimately affects Drosophila development.


Assuntos
Disruptores Endócrinos , Doenças Metabólicas , Animais , Clordano , Drosophila melanogaster , Insulina
8.
BMC Med Inform Decis Mak ; 21(1): 187, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34116660

RESUMO

BACKGROUND: Extensive clinical evidence suggests that a preventive screening of coronary heart disease (CHD) at an earlier stage can greatly reduce the mortality rate. We use 64 two-dimensional speckle tracking echocardiography (2D-STE) features and seven clinical features to predict whether one has CHD. METHODS: We develop a machine learning approach that integrates a number of popular classification methods together by model stacking, and generalize the traditional stacking method to a two-step stacking method to improve the diagnostic performance. RESULTS: By borrowing strengths from multiple classification models through the proposed method, we improve the CHD classification accuracy from around 70-87.7% on the testing set. The sensitivity of the proposed method is 0.903 and the specificity is 0.843, with an AUC of 0.904, which is significantly higher than those of the individual classification models. CONCLUSION: Our work lays a foundation for the deployment of speckle tracking echocardiography-based screening tools for coronary heart disease.


Assuntos
Doença das Coronárias , Ecocardiografia , Doença das Coronárias/diagnóstico por imagem , Humanos , Aprendizado de Máquina , Programas de Rastreamento , Reprodutibilidade dos Testes , Fatores de Risco
9.
Entropy (Basel) ; 23(2)2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33513817

RESUMO

The Nash equilibrium plays a crucial role in game theory. Most of results are based on classical resources. Our goal in this paper is to explore multipartite zero-sum game with quantum settings. We find that in two different settings there is no strategy for a tripartite classical game being fair. Interestingly, this is resolved by providing dynamic zero-sum quantum games using single quantum state. Moreover, the gains of some players may be changed dynamically in terms of the committed state. Both quantum games are robust against the preparation noise and measurement errors.

10.
BMC Bioinformatics ; 21(1): 520, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33183223

RESUMO

BACKGROUND: Protein kinases are a large family of druggable proteins that are genomically and proteomically altered in many human cancers. Kinase-targeted drugs are emerging as promising avenues for personalized medicine because of the differential response shown by altered kinases to drug treatment in patients and cell-based assays. However, an incomplete understanding of the relationships connecting genome, proteome and drug sensitivity profiles present a major bottleneck in targeting kinases for personalized medicine. RESULTS: In this study, we propose a multi-component Quantitative Structure-Mutation-Activity Relationship Tests (QSMART) model and neural networks framework for providing explainable models of protein kinase inhibition and drug response ([Formula: see text]) profiles in cell lines. Using non-small cell lung cancer as a case study, we show that interaction terms that capture associations between drugs, pathways, and mutant kinases quantitatively contribute to the response of two EGFR inhibitors (afatinib and lapatinib). In particular, protein-protein interactions associated with the JNK apoptotic pathway, associations between lung development and axon extension, and interaction terms connecting drug substructures and the volume/charge of mutant residues at specific structural locations contribute significantly to the observed [Formula: see text] values in cell-based assays. CONCLUSIONS: By integrating multi-omics data in the QSMART model, we not only predict drug responses in cancer cell lines with high accuracy but also identify features and explainable interaction terms contributing to the accuracy. Although we have tested our multi-component explainable framework on protein kinase inhibitors, it can be extended across the proteome to investigate the complex relationships connecting genotypes and drug sensitivity profiles.


Assuntos
Redes Neurais de Computação , Inibidores de Proteínas Quinases/química , Relação Quantitativa Estrutura-Atividade , Afatinib/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Lapatinib/farmacologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mutação , Medicina de Precisão , Mapas de Interação de Proteínas/efeitos dos fármacos , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia
11.
Avian Pathol ; 49(5): 448-456, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32374185

RESUMO

The avian EB66® cell line, derived from duck embryonic stem cells, has been widely used for producing human and animal therapeutic proteins and vaccines. In current study we evaluated the potential use of EB66® cell line in a cell culture-derived duck Tembusu virus (DTMUV) vaccine development. After optimizing the growth conditions of DTMUV HB strain in EB66® cells, we successfully generated three batches of viruses with ELD50 titres of 105.9/0.1 ml, 105.3/0.1 ml and 105.5/0.1 ml, respectively, for using in the preparation of inactivated vaccines. The immunogenicity and protective efficacy of these EB66® cells-derived inactivated vaccines were examined in ducks. Results indicated that all three batches of vaccines induced haemagglutination-inhibition (HI) antibody response in immunized birds at 2 weeks after a single immunization. Immunized ducks and ducklings were protected against a virulent challenge at 4 weeks after a booster immunization. The duration of immunity was for 3-4 months after a booster immunization. These results demonstrated the feasibility of using EB66® cell line to grow up DTMUV for vaccine preparation. RESEARCH HIGHLIGHTS Duck Tembusu virus can be propagated in EB66® cells. EB66® cell-derived inactivated DTMUV vaccines are immunogenic and can provide protection against a virulent challenge. A long-lasting immunity is induced after a booster immunization.


Assuntos
Anticorpos Antivirais/imunologia , Patos/virologia , Infecções por Flavivirus/veterinária , Flavivirus/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Virais/imunologia , Animais , Linhagem Celular , Feminino , Flavivirus/patogenicidade , Infecções por Flavivirus/prevenção & controle , Infecções por Flavivirus/virologia , Testes de Inibição da Hemaglutinação/veterinária , Imunização/veterinária , Imunogenicidade da Vacina , Masculino , Doenças das Aves Domésticas/virologia , Vacinas de Produtos Inativados/imunologia , Virulência
12.
J Chem Phys ; 150(4): 044111, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30709281

RESUMO

Free energy calculations for chemical reactions with a steep energy barrier require well defined reaction coordinates (RCs). However, when multiple parallel channels exist along selected RC, the application of conventional enhanced samplings is difficult to generate correct sampling within limited simulation time and thus cannot give correct prediction about the favorable pathways, the relative stability of multiple products or intermediates. Here, we implement the selective integrated tempering sampling (SITS) method with quantum mechanical and molecular mechanical (QM/MM) potential to investigate the chemical reactions in solution. The combined SITS-QM/MM scheme is used to identify possible reaction paths, intermediate and product states, and the free energy profiles for the different reaction paths. Two double proton transfer reactions were studied to validate the implemented method and simulation protocol, from which the independent and correlated proton transfer processes are identified in two representative systems, respectively. This protocol can be generalized to various kinds of chemical reactions for both academic studies and industry applications, such as in exploration and optimization of potential reactions in DNA encoded compound library and halogen or deuterium substitution of the hit discovery and lead optimization stages of drug design via providing a better understanding of the reaction mechanism along the designed chemical reaction pathways.

14.
PLoS Genet ; 11(3): e1005043, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25760041

RESUMO

Production of protein containing lengthy stretches of polyglutamine encoded by multiple repeats of the trinucleotide CAG is a hallmark of Huntington's disease (HD) and of a variety of other inherited degenerative neurological and neuromuscular disorders. Earlier work has shown that interference with production of the transcription elongation protein SUPT4H results in decreased cellular capacity to transcribe mutant huntingtin gene (Htt) alleles containing long CAG expansions, but has little effect on expression of genes containing short CAG stretches. zQ175 and R6/2 are genetically engineered mouse strains whose genomes contain human HTT alleles that include greatly expanded CAG repeats and which are used as animal models for HD. Here we show that reduction of SUPT4H expression in brains of zQ175 mice by intracerebroventricular bolus injection of antisense 2'-O-methoxyethyl oligonucleotides (ASOs) directed against Supt4h, or in R6/2 mice by deletion of one copy of the Supt4h gene, results in a decrease in mRNA and protein encoded specifically by mutant Htt alleles. We further show that reduction of SUPT4H in mouse brains is associated with decreased HTT protein aggregation, and in R6/2 mice, also with prolonged lifespan and delay of the motor impairment that normally develops in these animals. Our findings support the view that targeting of SUPT4H function may be useful as a therapeutic countermeasure against HD.


Assuntos
Proteínas de Ligação a DNA/genética , Doença de Huntington/genética , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Expansão das Repetições de Trinucleotídeos/genética , Alelos , Animais , Comportamento Animal , Encéfalo/metabolismo , Encéfalo/patologia , Proteínas de Ligação a DNA/biossíntese , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Proteína Huntingtina , Doença de Huntington/patologia , Camundongos , Mutação , Proteínas do Tecido Nervoso/biossíntese , Neurônios/metabolismo , Neurônios/patologia , Proteínas Nucleares/biossíntese , Agregação Patológica de Proteínas/genética , RNA Mensageiro/genética
15.
Bioorg Med Chem Lett ; 26(12): 2760-2763, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27155899

RESUMO

B-Raf(V600E) was an effective target for the treatment of human cancers. Based on a pan-Raf inhibitor TAK-632, a series of N-(4-aminopyridin-2-yl)amide derivatives were designed as novel B-Raf(V600E) inhibitors. Detailed structure-activity studies of the compounds revealed that most of the compounds displayed potent enzymatic activity against B-Raf(V600E), and good selectivity over B-Raf(WT). One of the most promising compound 4l exhibited potent inhibitory activity with an IC50 value of 38nM for B-raf(V600E), and displayed antiproliferative activities against colo205 and HT29 cells with IC50 values of 0.136 and 0.094µM, respectively. It also displayed good selectivity on both enzymatic and cellular assays over B-Raf(WT). These inhibitors may serve as lead compounds for further developing novel B-Raf(V600E) inhibitors as anticancer drugs.


Assuntos
Amidas/farmacologia , Antineoplásicos/farmacologia , Desenho de Fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Amidas/síntese química , Amidas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HT29 , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas B-raf/metabolismo , Relação Estrutura-Atividade
16.
Planta ; 241(1): 145-55, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25230699

RESUMO

MAIN CONCLUSION: The Ycf46 mutant of Synechocystis showed growth inhibition under low dissolved CO 2 conditions, suggesting a role for the Ycf46 protein in the process of photosynthetic CO 2 uptake and utilization. Hypothetical chloroplast open reading frame Ycf46 proteins are highly conserved in all cyanobacterial lineages and most algal chloroplast genomes, but their exact function is still unknown. In the cyanobacterium Synechocystis sp. PCC 6803, the Ycf46 encoding gene slr0374 is part of an operon (with slr0373 and slr0376) and responds to many environmental stresses. Transcript levels of the slr0373, slr0374 and slr0376 genes were increased under a low concentration of dissolved inorganic carbon (Ci). Compared with the wild type, the mutant lacking slr0374 showed growth arrest under Ci-deficient conditions but not under iron-deficient or low-light conditions. In addition, the mutant grew more slowly than the wild type under pH 6.0 conditions in which CO2 was the dominant Ci source, indicating the mutant cells had weak CO2 uptake and/or utilization ability. Supplying a high concentration of CO2 (5 %, v/v) to the mutant restored its phenotype to the wild type level. The photosynthetic activity of the mutant was inhibited to a lesser extent by a carbonic anhydrase inhibitor than that of the wild type, which specifically blocked CO2 uptake. Inactivation of slr0374 decreased expression of the ecaB gene and reduced carbonic anhydrase activity. A subcellular localization assay indicated that the Ycf46 protein was soluble. By co-immunoprecipitation assay using Slr0374 as a bait-protein, potential interacting proteins in the size range of 30 kDa were identified. These results suggest that the Ycf46 protein plays a role in the regulation of photosynthesis in cyanobacteria, especially in CO2 uptake and utilization.


Assuntos
Proteínas de Bactérias/metabolismo , Dióxido de Carbono/metabolismo , Óperon , Synechocystis/metabolismo , Proteínas de Bactérias/genética , Carbono/metabolismo , Regulação Bacteriana da Expressão Gênica , Concentração de Íons de Hidrogênio , Imunoprecipitação , Mutação , Fotossíntese/genética , Fotossíntese/fisiologia , Ligação Proteica , Synechocystis/genética
17.
Bioorg Med Chem Lett ; 25(19): 4277-81, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26259806

RESUMO

IGF1R amplification was recently implied to be related to the secondary acquired resistance against the 2nd or 3rd generation EGFR inhibitor therapies. We have successfully identified a series of 2,4-diarylamino-pyrimidines as new IGF1R/EGFR(L858R/T790M) co-targeting agents. One of the most promising compounds 8g potently inhibits both kinases with low nanomolar IC50 values, but is significantly less potent in inhibiting the wild type EGFR. The compound also displays a good kinase selectivity profile against a panel of 468 kinases. Moreover, 8g strongly suppresses the proliferation of CO-1686-resistant H1975-IGF1R cancer cells, suggesting its promising potential as a new lead compound for future anticancer drug discovery.


Assuntos
Antineoplásicos/farmacologia , Receptores ErbB/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Receptores de Somatomedina/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/metabolismo , Humanos , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Receptor IGF Tipo 1 , Receptores de Somatomedina/metabolismo , Relação Estrutura-Atividade
18.
Bioorg Med Chem Lett ; 24(17): 4250-3, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25091926

RESUMO

Emerging drug resistance and other drawbacks limit tubulin inhibitors' therapeutic applications and developing novel tubulin inhibitors still attracts intensive efforts. We describe the discovery and structure-activity relationship study of a series of benzimidazole-2-urea derivatives as novel ß tubulin inhibitors. The representative compound 6o potently suppressed the proliferation of a panel of human cancer cells (NCI-H460, Colo205, K562, A431, HepG2, Hela, MDA-MB-435S) with IC50 values of 0.040, 0.050, 0.006, 0.026, 1.774, 0.452 and 0.052 µM, respectively. Compound 6o obviously inhibited NCI-H460 spindles formation and induced cell cycle arrest at G2/M phase at 0.10 µM. Computational study suggested that 6o interacts with ß tubulin in a novel binding mode. Our results suggested that benzimidazole-2-urea derivatives might be promising tubulin inhibitors with novel binding mode for further development.


Assuntos
Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , Compostos de Metilureia/farmacologia , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Benzimidazóis/síntese química , Benzimidazóis/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Fase G2/efeitos dos fármacos , Células HeLa , Células Hep G2 , Humanos , Células K562 , Compostos de Metilureia/síntese química , Compostos de Metilureia/química , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Moduladores de Tubulina/síntese química
19.
J Integr Plant Biol ; 56(4): 373-87, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24279300

RESUMO

Phytochrome-interacting factors (PIFs) regulate an array of developmental responses ranging from seed germination to vegetational architecture in Arabidopsis. However, information regarding the functions of the PIF family in monocots has not been widely reported. Here, we investigate the roles of OsPIL15, a member of the rice (Oryza sativa L. cv. Nipponbare) PIF family, in regulating seedling growth. OsPIL15 encodes a basic helix-loop-helix factor localized in the nucleus. OsPIL15-OX seedlings exhibit an exaggerated shorter aboveground part and undeveloped root system relative to wild-type seedlings, suggesting that OsPIL15 represses seedling growth in the dark. Microarray analysis combined with gene ontology analysis revealed that OsPIL15 represses a set of genes involved in auxin pathways and cell wall organization or biogenesis. Given the important roles of the auxin pathway and cell wall properties in controlling plant growth, we speculate that OsPIL15 represses seedling growth likely by regulating the auxin pathway and suppressing cell wall organization in etiolated rice seedlings. Additionally, exposure to red light or far-red light relieved growth retardation and promoted seedling elongation in the OsPIL15-OX lines, despite higher levels of OsPIL15 transcripts under red light and far-red light than in the dark. These results suggest that light regulation of OsPIL15 expression is probably involved in photomorphogenesis in rice.


Assuntos
Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plântula/genética
20.
Adv Mater ; : e2406957, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38923059

RESUMO

Single-atom catalysts (SACs) are flourishing in various fields because of their 100% atomic utilization. However, their uncontrollable selectivity, poor stability and vulnerable inactivation remain critical challenges. According to theoretical predictions and experiments, a heteronuclear CoZn dual-single-atom confined in N/O-doped hollow carbon nanotube reactors (CoZnSA@CNTs) is synthesized via spatial confinement growth. CoZnSA@CNTs exhibit superior performance for H2O2 electrosynthesis over the entire pH range due to dual-confinement of atomic sites and O2 molecule. CoZnSA@CNTs is favorable for H2O2 production mainly because the synergy of adjacent atomic sites, defect-rich feature and nanotube reactor promoted O2 enrichment and enhanced H2O2 reactivity/selectivity. The H2O2 selectivity reaches ∼100% in a range of 0.2-0.65 V versus RHE and the yield achieves 7.50 M gcat -1 with CoZnSA@CNTs/carbon fiber felt, exceeding most of the reported SACs in H-type cells. The obtained H2O2 is converted directly to sodium percarbonate and sodium perborate in a safe way for H2O2 storage/transportation. The sequential dual-cathode electron-Fenton process promotes the formation of reactive oxygen species (•OH, 1O2 and •O2 -) by activating the generated H2O2, enabling accelerated degradation of various pollutants and Cr(VI) detoxification in actual wastewater. This work proposes a promising confinement strategy for catalyst design and selectivity regulation of complex reactions.

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