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1.
Dev Cell ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38823394

RESUMO

Embryonic stem cells (ESCs) can differentiate into all cell types of the embryonic germ layers. ESCs can also generate totipotent 2C-like cells and trophectodermal cells. However, these latter transitions occur at low frequency due to epigenetic barriers, the nature of which is not fully understood. Here, we show that treating mouse ESCs with sodium butyrate (NaB) increases the population of 2C-like cells and enables direct reprogramming of ESCs into trophoblast stem cells (TSCs) without a transition through a 2C-like state. Mechanistically, NaB inhibits histone deacetylase activities in the LSD1-HDAC1/2 corepressor complex. This increases acetylation levels in the regulatory regions of both 2C- and TSC-specific genes, promoting their expression. In addition, NaB-treated cells acquire the capacity to generate blastocyst-like structures that can develop beyond the implantation stage in vitro and form deciduae in vivo. These results identify how epigenetics restrict the totipotent and trophectoderm fate in mouse ESCs.

2.
Front Cell Dev Biol ; 11: 1288431, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38020878

RESUMO

Introduction: Mathematical model can be used to model complex biological processes, and have shown potential in describing apoptosis in chondrocytes. Method: In order to investigate the regulatory mechanisms of TNF signaling pathway in regulating chondrocyte apoptosis, a fractional-order differential equation model is proposed to describe the dynamic behavior and mutual interaction of apoptosis-related genes under the activation of TNF signaling pathway. Compared with the traditional molecular biology techniques, the proposed mathematical modeling has advantages to providing a more comprehensive understanding of the regulatory mechanisms of TNF signaling pathway in chondrocyte apoptosis. Result: In this paper, differentially expressed genes induced by IL-1ß in human chondrocyte apoptosis are screened using high-throughput sequencing. It is found that they were significantly enriched in the TNF signaling pathway. Therefore, a mathematical model of the TNF signaling pathway is built. Using real-time PCR experiments, mRNA data is measured and used to identify the model parameters, as well as the correlation coefficient. Finally, the sensitivity of the model parameters is discussed by using numerical simulation methods, which can be used to predict the effects of different interventions and explore the optimal intervention strategies for regulating chondrocyte apoptosis. Discussion: Therefore, fractional-order differential equation modeling plays an important role in understanding the regulatory mechanisms of TNF signaling pathway in chondrocyte apoptosis and its potential clinical applications.

3.
Dev Cell ; 58(22): 2510-2527.e7, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37875119

RESUMO

Generating cells with the molecular and functional properties of embryo cells and with full developmental potential is an aim with fundamental biological significance. Here we report the in vitro generation of mouse transient morula-like cells (MLCs) via the manipulation of signaling pathways. MLCs are molecularly distinct from embryonic stem cells (ESCs) and cluster instead with embryo 8- to 16-cell stage cells. A single MLC can generate a blastoid, and the efficiency increases to 80% when 8-10 MLCs are used. MLCs make embryoids directly, efficiently, and within 4 days. Transcriptomic analysis shows that day 4-5 MLC-derived embryoids contain the cell types found in natural embryos at early gastrulation. Furthermore, MLCs introduced into morulae segregate into epiblast (EPI), primitive endoderm (PrE), and trophectoderm (TE) fates in blastocyst chimeras and have a molecular signature indistinguishable from that of host embryo cells. These findings represent the generation of cells that are molecularly and functionally similar to the precursors of the first three cell lineages of the embryo.


Assuntos
Blastocisto , Embrião de Mamíferos , Animais , Camundongos , Mórula/metabolismo , Blastocisto/metabolismo , Linhagem da Célula , Embrião de Mamíferos/metabolismo , Células-Tronco Embrionárias , Desenvolvimento Embrionário/fisiologia
4.
Sci China Life Sci ; 66(3): 423-435, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36633710

RESUMO

Mammalian embryogenesis begins with a totipotent zygote. Blastocyst-like structures can be captured by aggregated cells with extended pluripotent properties in a three-dimensional (3D) culture system. However, the efficiency of generating blastoids is low, and it remains unclear whether other reported totipotent-like stem cells retain a similar capacity. In this study, we demonstrated that spliceosomal repression-induced totipotent blastomere-like cells (TBLCs) form blastocyst-like structures within around 80% of all microwells. In addition, we generated blastoids initiating from a single TBLC. TBLC-blastoids express specific markers of constituent cell lineages of a blastocyst and resemble blastocyst in cell-lineage allocation. Moreover, single-cell RNA sequencing revealed that TBLC-blastoids share a similar transcriptional profile to natural embryos, albeit composed of fewer primitive endoderm-like cells. Furthermore, TBLC-blastoids can develop beyond the implantation stage in vitro and induce decidualization in vivo. In summary, our findings provided an alternative cell type to efficiently generate blastoids for the study of early mouse embryogenesis.


Assuntos
Blastômeros , Spliceossomos , Animais , Camundongos , Diferenciação Celular/genética , Spliceossomos/genética , Blastocisto/metabolismo , Linhagem da Célula , Desenvolvimento Embrionário/genética , Embrião de Mamíferos , Mamíferos
5.
Gastric Cancer ; 24(1): 72-84, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32529327

RESUMO

BACKGROUND: Gastric cancer (GC) is a leading cause of cancer-related mortality worldwide, because of the low efficacy of current therapeutic strategies. Estrogen-related receptor γ (ERRγ) was previously showed as a suppressor of GC. However, the mechanism and effective therapeutic method based on ERRγ is yet to be developed. METHODS: The expression levels of ERRγ, EZH2, and FOXM1 were detected by immunohistochemistry, qRT-PCR, and western blot. The regulatory mechanisms of ERRγ and FOXM1 were analyzed by ChIP, EMSA, and siRNA. The effects of EZH2 inhibitor (GSK126) or/and ERRγ agonist (DY131) on the tumorigenesis of gastric cancer cell lines were examined by cell proliferation, transwell migration, wound healing, and colony formation assays. Meanwhile, the inhibitory effects of GSK126 or/and DY131 on tumor growth were analyzed by xenograft tumor growth assay. RESULTS: The expression of ERRγ was suppressed in tumor tissues of GC patients and positively correlated with prognosis, as opposed to that of EZH2 and FOXM1. EZH2 transcriptionally suppressed ERRγ via H3K27me3, which subsequently activated the expression of master oncogene FOXM1. The combination of GSK126 and DY131 synergistically activated ERRγ expression, which subsequently inhibited the expression of FOXM1 and its regulated pathways. Synergistic combination of GSK126 and DY131 significantly inhibited the tumorigenesis of GC cell lines and suppressed the growth of GC xenograft. CONCLUSION: The FOXM1 signaling pathway underlying the ERRγ-mediated gastric cancer suppression was identified. Furthermore, combined treatment with EZH2 inhibitor and ERRγ agonist synergistically suppressed GC progression by inhibiting this signaling pathway, suggesting its high potential in treating GC patients.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Proteína Forkhead Box M1/efeitos dos fármacos , Hidrazinas/farmacologia , Indóis/farmacologia , Piridonas/farmacologia , Receptores de Estrogênio/efeitos dos fármacos , Neoplasias Gástricas/tratamento farmacológico , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Linhagem Celular Tumoral , Quimioterapia Combinada , Regulação Neoplásica da Expressão Gênica , Humanos , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/genética , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Onco Targets Ther ; 13: 9123-9133, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32982301

RESUMO

BACKGROUND: Peroxiredoxin 1 (PRDX1) has been identified as a dual regulator of tumorigenesis. However, its expression, clinical significance, and biological function in nasopharyngeal carcinoma (NPC) remain unknown. This study aimed to explore the role and underlying mechanisms of PRDX1 in NPC. MATERIALS AND METHODS: The expression of PRDX1 in NPC tissues was evaluated by immunohistochemistry, and the relationships between the expression of PRDX1 and clinical features and prognosis of NPC patients were analyzed. The effects of PRDX1 on NPC cell proliferation, migration, invasion, and epithelial-to-mesenchymal transition (EMT) were examined. A tumor-bearing model of nude mouse was established to verify the function of PRDX1 in vivo. RESULTS: PRDX1 expression level was negatively associated with recurrence and metastasis of NPC. PRDX1 knockdown promoted NPC cell proliferation, migration, invasion and EMT in vitro, and enhanced tumor growth in vivo, while PRDX1 overexpression had opposite effects. Furthermore, transcriptome analysis showed that PRDX1 inhibited the activation of PI3K/AKT/TRAF1 signaling in NPC cells. CONCLUSION: PRDX1 inhibits NPC by inhibiting the activation of PI3K/AKT/TRAF1 signaling. PRDX1 is a tumor suppressor in human NPC and may be a prognostic biomarker for NPC patients.

7.
Int J Mol Sci ; 21(18)2020 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-32899983

RESUMO

Aflatoxin B1 (AFB1) is a mycotoxin widely distributed in a variety of food commodities and exhibits strong toxicity toward multiple tissues and organs. However, little is known about its neurotoxicity and the associated mechanism. In this study, we observed that brain integrity was markedly damaged in mice after intragastric administration of AFB1 (300 µg/kg/day for 30 days). The toxicity of AFB1 on neuronal cells and the underlying mechanisms were then investigated in the neuroblastoma cell line IMR-32. A cell viability assay showed that the IC50 values of AFB1 on IMR-32 cells were 6.18 µg/mL and 5.87 µg/mL after treatment for 24 h and 48 h, respectively. ROS levels in IMR-32 cells increased significantly in a time- and AFB1 concentration-dependent manner, which was associated with the upregulation of NOX2, and downregulation of OXR1, SOD1, and SOD2. Substantial DNA damage associated with the downregulation of PARP1, BRCA2, and RAD51 was also observed. Furthermore, AFB1 significantly induced S-phase arrest, which is associated with the upregulation of CDKN1A, CDKN2C, and CDKN2D. Finally, AFB1 induced apoptosis involving CASP3 and BAX. Taken together, AFB1 manifests a wide range of cytotoxicity on neuronal cells including ROS accumulation, DNA damage, S-phase arrest, and apoptosis-all of which are key factors for understanding the neurotoxicology of AFB1.


Assuntos
Aflatoxina B1/toxicidade , Apoptose/efeitos dos fármacos , Dano ao DNA , Síndromes Neurotóxicas , Espécies Reativas de Oxigênio/metabolismo , Fase S/efeitos dos fármacos , Aflatoxina B1/farmacologia , Animais , Apoptose/fisiologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Dano ao DNA/fisiologia , Masculino , Camundongos , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Fase S/genética
8.
Cell Death Dis ; 11(9): 761, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934214

RESUMO

Chronic stress could induce cancer metastasis by constant activation of the sympathetic nervous system, while cellular mechanism remains obscure. The aim of this research is to explore the metastasis associated negative effect of chronic stress. The analysis of transcriptome sequencing implied that activation of STAT3 signaling pathway by downregulated miR-337-3p might be a potential mechanism to induce epithelial to mesenchymal transition (EMT) of cancer cell and promote metastasis under chronic stress. We also verified this biological process in further experiments. Downregulation of miR-337-3p could downregulate E-cadherin expression and upregulate vimentin expression in vitro and in vivo. STAT3, related signal pathways of which are involved in metastasis regulation, was directly targeted by miR-337-3p. In conclusion, the above results denoted that activation of miR-337-3p/STAT3 axis might be a potential pathway for the increasing metastasis of breast cancer under chronic stress.


Assuntos
Neoplasias Mamárias Experimentais/metabolismo , MicroRNAs/metabolismo , Fator de Transcrição STAT3/metabolismo , Estresse Psicológico/metabolismo , Animais , Doença Crônica , Transição Epitelial-Mesenquimal , Feminino , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , Metástase Neoplásica , Fator de Transcrição STAT3/genética , Transdução de Sinais , Estresse Psicológico/genética , Estresse Psicológico/patologia
9.
Biochem Pharmacol ; 175: 113897, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32135158

RESUMO

Deoxynivalenol (DON) is a mycotoxin produced by multipleFusariumspecies that often contaminates cereals and threatens human and animal health. A wide range of cytotoxic effects, such as the induction of DNA damage, an increase in mitochondrial permeability and the inhibition of macromolecule synthesis, have been reported. However, the effects of DON on cell migration-a fundamental process in living cells critical for normal development, immune responses, and disease processes-and the mechanism underlying these effects are still unclear. Here, we showed that DONsignificantly inhibited the migration of MRC-5, CCD-18Co, HCT116 and WM793 cells at 50 ng/ml, 50 ng/ml, 400 ng/ml and 250 ng/ml, respectively, which maintained cell viability at 90%. Further analysis showed that DON inhibited the expression of tumour endothelial marker 8 (TEM8), a key gene in cell migration. Furthermore, we showed that DON inhibited the expression of TEM8 through increasing the level of H3K27me3 in the TEM8 promoter. Finally, overexpression of TEM8 or treating by H3K27me3-specific inhibitor GSK126 attenuated the inhibitory effect of DON on cell migration. In summary, low doses of DON at approximately dietary exposure significantly inhibited cell migration by downregulating the expression of TEM8 in a manner mediated by H3K27me3, which may generate increasing concerns for the risk of DON exposure.


Assuntos
Movimento Celular/fisiologia , Regulação para Baixo/fisiologia , Regulação Neoplásica da Expressão Gênica , Histonas/biossíntese , Proteínas dos Microfilamentos/biossíntese , Receptores de Superfície Celular/biossíntese , Tricotecenos/farmacologia , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Células HCT116 , Histonas/genética , Humanos , Proteínas dos Microfilamentos/antagonistas & inibidores , Proteínas dos Microfilamentos/genética , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/genética
10.
FEBS J ; 286(21): 4215-4231, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31199573

RESUMO

Cytochrome P450 1A1 (CYP1A1) is abundant in the kidney, liver, and intestine and is involved in the phase I metabolism of numerous endogenous and exogenous compounds. Therefore, exploring the regulatory mechanism of its basal expression in humans is particularly important to understand the bioactivation of several procarcinogens to their carcinogenic derivatives. Site-specific mutagenesis and deletion of the transcription factor binding site determined the core cis-acting elements in the human CYP1A1 proximal and distal promoter regions. The proximal promoter region [overlapping xenobiotic-responsive element (XRE) and GC box sequences] determined the basal expression of CYP1A1. In human hepatocellular carcinoma cells (HepG2) with aryl hydrocarbon receptor (AhR) or specificity protein 1 (Sp1) knockdown, we confirmed that AhR and Sp1 are involved in basal CYP1A1 expression. In HepG2 cells overexpressing either AhR or Sp1, AhR determined the proximal transactivation of basal CYP1A1 expression. Via DNA affinity precipitation assays and ChIP, we found that AhR bound to the promoter and recruited Sp1 to transactivate CYP1A1 expression. The coordinated interaction between Sp1 and AhR was identified to be DNA mediated. Our work revealed a basal regulatory mechanism of an interesting human gene by which AhR interacts with Sp1 through DNA and recruits Sp1 to regulate basal CYP1A1 expression.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Citocromo P-450 CYP1A1/genética , Neoplasias/genética , Receptores de Hidrocarboneto Arílico/genética , Fator de Transcrição Sp1/genética , Carcinógenos/toxicidade , Regulação da Expressão Gênica/genética , Células Hep G2 , Humanos , Mucosa Intestinal/metabolismo , Rim/metabolismo , Fígado/metabolismo , Desintoxicação Metabólica Fase I/genética , Neoplasias/induzido quimicamente , Neoplasias/patologia , Regiões Promotoras Genéticas , Ligação Proteica/genética , Ativação Transcricional/genética
11.
Micromachines (Basel) ; 10(5)2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31121955

RESUMO

High-precision aligned wafer bonding is essential to heterogeneous integration, with the device dimension reduced continuously. To get the alignment more accurately and conveniently, we propose a moiré-based alignment method using centrosymmetric grating marks. This method enables both coarse and fine alignment steps without requiring additional conventional cross-and-box alignment marks. Combined with an aligned wafer bonding system, alignment accuracy better than 300 nm (3σ) was achieved after bonding. Furthermore, the working principle of the moiré-based alignment for the backside alignment system was proposed to overcome the difficulty in bonding of opaque wafers. We believe this higher alignment accuracy is feasible to satisfy more demanding requirements in wafer-level stacking technologies.

12.
Biochem Pharmacol ; 166: 108-119, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31075264

RESUMO

Aflatoxin B1 (AFB1), a member of the aflatoxin family, is a common contaminant in foods and feeds, and AFB1 exposure is associated with various clinical conditions. Thus far, research on the toxicity of AFB1 has mainly focused on its induction of liver cancer, but little research has been reported on renal toxicity, especially with regards to the underlying molecular mechanisms. In this study, we found that AFB1 treatment significantly induced kidney damage and reduced kidney weight. The human kidney cell line HEK293T was used to further study the molecular mechanism of the toxicity of AFB1 to kidney cells. We found that AFB1 significantly and dose-dependently induced S phase arrest and upregulated p21 mRNA and protein expression. Upstream of p21, three negative regulators, PLK1, MYC, and PLD1, were significantly downregulated under AFB1 treatment. Consistently, p21 was upregulated, and PLK1, MYC and PLD1 were downregulated in mouse kidney after AFB1 treatment. Interestingly, AFB1 also decreased the physical interaction between PLK1 and MYC and weakened the stability of the MYC protein. Importantly, overexpression of PLK1, MYC and PLD1 significantly blocked the upregulation of p21 and attenuated the S phase arrest caused by AFB1. In summary, AFB1 markedly induces kidney damage and strongly induces S phase arrest by upregulating the expression of p21 via PLK1, PLD1 and MYC, which represents a noval mechanism of the renal toxicity of AFB1.


Assuntos
Aflatoxina B1/farmacologia , Proteínas de Ciclo Celular/biossíntese , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Genes myc/efeitos dos fármacos , Fosfolipase D/biossíntese , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Proto-Oncogênicas/biossíntese , Fase S/efeitos dos fármacos , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/fisiologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Relação Dose-Resposta a Droga , Expressão Gênica , Genes myc/fisiologia , Células HEK293 , Humanos , Masculino , Camundongos , Fosfolipase D/antagonistas & inibidores , Fosfolipase D/genética , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Fase S/fisiologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia , Quinase 1 Polo-Like
13.
Biochem Pharmacol ; 166: 12-22, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31075268

RESUMO

The type B trichothecene mycotoxin deoxynivalenol (DON), colloquially known as "vomitoxin", is the most commonly detected trichothecene in cereal-based foods, exerting acute and chronic toxic effects on animals and causing serious safety-related concerns. At the cellular and molecular levels, DON can inhibit macromolecule synthesis by binding to ribosomes and may disrupt cell proliferation, differentiation and apoptosis. However, the molecular mechanisms underlying the cytotoxicity of DON remain to be determined. Here, we identified ß-catenin, the key signal transducer of the Wnt cascade, as a novel target of DON by quantitative real-time PCR and Western blot analysis in human embryonic kidney 293T and colorectal SW480 cells treated with DON at half IC50 (50 ng/mL for HEK293T and 1 µg/mL for SW480). Further analysis showed that neither posttranslationalmodification nor nuclear accumulation of ß-catenin was affected post DON treatment. Moreover, we found that the ß-catenin-dependent canonical Wnt signaling pathway, which regulates many biological processes during embryonic development and adult tissue homeostasis, was involved in DON-induced inhibition of cell proliferation. Then, we determined that the ß-catenin/c-Myc axis was essential for this process, as the DON-induced inhibition of cell proliferation was efficiently rescued by restoration of ß-catenin or c-Myc levels. Our results advance the current understanding of the molecular toxicological mechanism of DON and provide a new perspective on strategies for the prevention and control of mycotoxins.


Assuntos
Proliferação de Células/efeitos dos fármacos , Tricotecenos/toxicidade , Via de Sinalização Wnt/efeitos dos fármacos , Proteína Wnt3A/antagonistas & inibidores , beta Catenina/antagonistas & inibidores , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Via de Sinalização Wnt/fisiologia , Proteína Wnt3A/metabolismo , beta Catenina/metabolismo
14.
Anal Chim Acta ; 1053: 139-147, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30712559

RESUMO

The development of biosensors that are portable, low-cost, and quantitative has long been sought for rapid, on-site, and timely detection of avian influenza virus (AIV). In this study, an antibody-based Raman lateral flow immunoassay strip was developed to detect AIV H7N9. This LFIA strip used a novel core-shell structure material, AuAg4-ATP@AgNPs, as a Raman probe. An antibody specific for AIV and goat anti-mouse IgG antibody were immobilized on a nitrocellulose membrane as the test and control lines, respectively. Accumulation of antibody-virus-antibody-Raman probe complex at the test line could be visualized by the naked eye, and the Raman signal could be quantified using a portable Raman instrument. The testing process for the SERS-based LFIA strips could be completed in 20 min, which avoided the time-cost of current methods for AIV analysis. In our SERS-based biosensor, we estimated the limit of detection (LOD) for H7N9 to be 0.0018 HAU. This value is approximately three orders of magnitude more sensitive than the corresponding HA assays. When testing real sample, the results of the strip test were in accordance with those from real-time PCR testing. In conclusion, the SERS-based LFIA strip proposed in this study shows tremendous potential to detect targets quickly and sensitively using an elegantly simple method.


Assuntos
Imunoensaio/métodos , Subtipo H7N9 do Vírus da Influenza A/isolamento & purificação , Limite de Detecção , Análise Espectral Raman/métodos , Animais
15.
Toxicol Lett ; 299: 95-103, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30286430

RESUMO

Deoxynivalenol (DON) is a type B trichothecene mycotoxin that exerts multiple toxic effects on plants, animals and humans. Several reports have shown that DON leads to G2/M cell cycle arrest. However, its molecular mechanism is still unclear. In this study, we showed that DON induced strong G2/M cell cycle arrest in HepG2 cells, and the cell cycle-inhibitory protein p21 was highly upregulated by DON. Further analysis showed that the cell cycle regulating gene EGR1 was highly induced by DON and that EGR1 knockdown abolished the upregulation of p21 and G2/M cell cycle arrest. Furthermore, we showed that the induction of EGR1 was regulated by the stress-responsive transcription factor ATF3. ATF3ΔZip2a/2b, which is a DNA binding domain truncated isoform of ATF3, was upregulated by DON. ATF3 knockdown weakened the expression induction of EGR1 and G2/M cell cycle arrest by DON. Moreover, the upregulation of ATF3ΔZip2a/2 highly depended on the enhanced presence of histones H3K9ac and H3K27ac. H3K9ac and H3K27ac were enriched at the promoter region of ATF3 following the DON treatment, and the knocking down of the genes responsible for H3K9ac and H3K27ac abolished the upregulation of ATF3 by DON. In summary, we found that DON induced G2/M cell cycle arrest by sequentially inducing the expression of ATF3ΔZip2a/2b, EGR1 and p21, and EGR1 played an essential role in this process, which is a novel molecular mechanism of cell cycle arrest by DON and is important for understanding its toxicology.


Assuntos
Fator 3 Ativador da Transcrição/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Tricotecenos/toxicidade , Fator 3 Ativador da Transcrição/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Células Hep G2 , Histonas/genética , Humanos , Plasmídeos , Transdução de Sinais , Transfecção , Regulação para Cima
16.
Medicine (Baltimore) ; 97(18): e0588, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29718859

RESUMO

With the development of palliative care, a signed do-not-resuscitate (DNR) order has become increasingly popular worldwide. However, there is no legal guarantee of a signed DNR order for patients with cancer in mainland China. This study aimed to estimate the status of DNR order signing before patient death in the cancer center of a large tertiary affiliated teaching hospital in western China. Patient demographics and disease-related characteristics were also analyzed.This was a retrospective chart analysis. We screened all charts from a large-scale tertiary teaching hospital in China for patients who died of cancer from January 2010 to February 2015. Analysis included a total of 365 records. The details of DNR order forms, patient demographics, and disease-related characteristics were recorded.The DNR order signing rate was 80%. Only 2 patients signed the DNR order themselves, while the majority of DNR orders were signed by patients' surrogates. The median time for signing the DNR order was 1 day before the patients' death. Most DNR decisions were made within the last 3 days before death. The time at which DNR orders were signed was related to disease severity and the rate of disease progression.Our findings indicate that signing a DNR order for patients with terminal cancer has become common in mainland China in recent years. Decisions about a DNR order are usually made by patients' surrogates when patients are severely ill. Palliative care in mainland China still needs to be improved.


Assuntos
Neoplasias/terapia , Cuidados Paliativos , Ordens quanto à Conduta (Ética Médica) , Cuidadores/psicologia , China , Tomada de Decisões , Feminino , Hospitais de Ensino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/psicologia , Estudos Retrospectivos , Fatores de Tempo
17.
Psychooncology ; 26(8): 1120-1125, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27709737

RESUMO

OBJECTIVES: The objective of the study is to develop a novel tool-the Burnout Battery-for briefly screening burnout among oncology professionals in China and assessing its validity. METHODS: A multicenter study was conducted in doctors and nurses of the oncology departments in China from November 2014 to May 2015. The Burnout Battery was administered with the Maslach Burnout Inventory-Human Services Survey (MBI-HSS) and the Doctors' Job Burnout Questionnaire. RESULTS: Of 538 oncology doctors and nurses who completed all the survey, using MBI-HSS as the standard tool for measuring burnout, 52% had emotional exhaustion, 39.4% had depersonalization, and 59.3% had a low sense of personal accomplishment. Receiver operating characteristic curve analyses showed that the best cut-off of the Burnout Battery was the battery with 3 bars, which yielded best sensitivity and specificity against all the 3 subscales of MBI-HSS. With this cut-off, nearly half of Chinese oncology professionals (46.8%) had burnout. The Burnout Battery correlated significantly with subscales of the MBI-HSS and the Doctors' Job Burnout Questionnaire. In multiple logistic regression analysis, those who worked more than 60 hours per week and who thought clinical work was the most stressful part of their job were more likely to experience burnout. CONCLUSION: Chinese oncology professionals exhibit high levels of burnout. The Burnout Battery appears to be a simple and useful tool for screening burnout. Working long hours and perceiving clinical work as the most stressful part of the job were the main factors associated with burnout.


Assuntos
Esgotamento Profissional/psicologia , Satisfação no Emprego , Corpo Clínico/psicologia , Inquéritos e Questionários/normas , Logro , Adulto , China , Despersonalização/psicologia , Feminino , Humanos , Masculino , Oncologia/organização & administração , Pessoa de Meia-Idade , Escala Visual Analógica
18.
Pol J Vet Sci ; 19(1): 21-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27096784

RESUMO

Avian pathogenic Escherichia coli (APEC) is a major bacterial infectious disease that may lead to local or systemic infections in chickens with clinical manifestations. The irp2-fyuA gene cluster has been confirmed to be the main genes involved in the synthesis of HPI. The objective of this study was to determine the influence of the irp2 and fyuA genes in the high pathogenicity island (HPI) of avian pathogenic Escherichia coli (APEC) on its pathogenicity by knocking out these genes. The ΔAE17 (lacking irp2) and ΔΔAE17 (lacking irp2 and fyuA) strains of APEC were constructed. The ΔAE17 and ΔΔAE17 strains showed significantly impaired capacity to adhere onto DF-1 cells. The LD50 results indicated that the virulence of the ΔAE17 and ΔΔAE17 strains was decreased in comparison with that of the AE17 strain. We concluded that the knock-out of the core HPI genes weakened APEC adhesion onto DF-1 cells, inhibited transcription of virulence genes, and reduced pathogenicity in chicks. The effects of genetic deletion of irp2 and fyuA on APEC were more severe than those produced by deletion of irp2 only, indicating that irp2 and fyuA co-regulate APEC pathogenicity.


Assuntos
Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Ilhas Genômicas/genética , Proteína 2 Reguladora do Ferro/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Aderência Bacteriana/genética , Aderência Bacteriana/fisiologia , Galinhas , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Proteína 2 Reguladora do Ferro/genética , Mutação , Doenças das Aves Domésticas/microbiologia , Receptores de Superfície Celular/genética , Transcrição Gênica
19.
Pol J Vet Sci ; 19(1): 31-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27096785

RESUMO

Avian pathogenic Escherichia coli (APEC) infections are a very important problem in the poultry industry. PhoP-PhoQ is a two-component system that regulates virulence genes in APEC. In this study, we constructed strains that lacked the PhoP or PhoQ genes to assess regulation of APEC pathogenicity by the PhoP-PhoQ two-component system. The PhoP mutant strain AE18, PhoQ mutant strain AE19, and PhoP/PhoQ mutant strain AE20 were constructed by the Red homologous recombination method. Swim plates were used to evaluate the motility of the APEC strains, viable bacteria counting was used to assess adhesion and invasion of chick embryo fibroblasts, and Real-Time PCR was used to measure mRNA expression of virulence genes. We first confirmed that AE18, AE19, and AE20 were successfully constructed from the wild-type AE17 strain. AE18, AE19, and AE20 showed significant decreases in motility of 70.97%, 83.87%, and 37.1%, respectively, in comparison with AE17. Moreover, in comparison with AE17, AE18, AE19, and AE20 showed significant decreases of 63.11%, 65.42%, and 30.26%, respectively, in CEF cell adhesion, and significant decreases of 59.83%, 57.82%, and 37.90%, respectively, in CEF cell invasion. In comparison with AE17, transcript levels of sodA, polA, and iss were significantly decreased in AE18, while transcript levels of fimC and iss were significantly decreased in AE19. Our results demonstrate that deletion of PhoP or PhoQ inhibits invasion and adhesion of APEC to CEF cells and significantly reduces APEC virulence by regulating transcription of virulence genes.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Escherichia coli/patogenicidade , Regulação Bacteriana da Expressão Gênica/fisiologia , Fatores de Virulência/metabolismo , Animais , Aderência Bacteriana/fisiologia , Galinhas , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Feminino , Mutação , Doenças das Aves Domésticas/microbiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Virulência , Fatores de Virulência/genética
20.
Ann Transl Med ; 4(4): 73, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27004220

RESUMO

BACKGROUND: The objective is to assess how cancer patients know about their diagnosis what they know about their real stage, and the relationship between cancer stage and psychological distress. METHODS: A questionnaire including the Distress Thermometer was delivered to 422 cancer inpatients. Multivariate logistic regression analysis was used to estimate odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Most of patients (68.7%) knew the bad news immediately after diagnosis. Half of patients knew their diagnosis directly from medical reports. Nearly one third of patients were informed by doctors. Cancer stages, which patients believed, differed significantly from their real disease stages (P<0.001). Over half of patients did not know their real disease stages. Patients with stage I-III cancer were more likely to know their real disease stage than patients with stage IV cancer (P<0.001). Distress scores of cancer patients were determined by the real cancer stage (P=0.012), not the stage which patients believed. CONCLUSIONS: Although most of participants knew the bad news immediately after diagnosis, less than half of them knew their real disease stage. Patient with stage I-III cancer was more likely to know the real disease stage and had a DT score <4 than patient with stage IV disease.

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