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1.
Cell ; 183(5): 1234-1248.e25, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33113353

RESUMO

Brain metastasis (br-met) develops in an immunologically unique br-met niche. Central nervous system-native myeloid cells (CNS-myeloids) and bone-marrow-derived myeloid cells (BMDMs) cooperatively regulate brain immunity. The phenotypic heterogeneity and specific roles of these myeloid subsets in shaping the br-met niche to regulate br-met outgrowth have not been fully revealed. Applying multimodal single-cell analyses, we elucidated a heterogeneous but spatially defined CNS-myeloid response during br-met outgrowth. We found Ccr2+ BMDMs minimally influenced br-met while CNS-myeloid promoted br-met outgrowth. Additionally, br-met-associated CNS-myeloid exhibited downregulation of Cx3cr1. Cx3cr1 knockout in CNS-myeloid increased br-met incidence, leading to an enriched interferon response signature and Cxcl10 upregulation. Significantly, neutralization of Cxcl10 reduced br-met, while rCxcl10 increased br-met and recruited VISTAHi PD-L1+ CNS-myeloid to br-met lesions. Inhibiting VISTA- and PD-L1-signaling relieved immune suppression and reduced br-met burden. Our results demonstrate that loss of Cx3cr1 in CNS-myeloid triggers a Cxcl10-mediated vicious cycle, cultivating a br-met-promoting, immune-suppressive niche.


Assuntos
Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/secundário , Quimiocina CXCL10/metabolismo , Terapia de Imunossupressão , Células Mieloides/metabolismo , Animais , Células da Medula Óssea/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Receptor 1 de Quimiocina CX3C/metabolismo , Sistema Nervoso Central/patologia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Interferons/metabolismo , Macrófagos/metabolismo , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Testes de Neutralização , Fenótipo , Linfócitos T/imunologia , Transcriptoma/genética
2.
Opt Express ; 32(3): 3234-3240, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297549

RESUMO

In this work, the momentum mismatching based on which the acousto-optic (AO) transfer function and diffraction efficiency was acquired, was calculated considering the properties of AO crystals in AO interactions in acousto-optic tunable filter (AOTF). Transfer functions were obtained using a 4f optical system combined with AOTF and compared with theoretical calculations. It demonstrated the influence of acoustic energy shift on the AO interaction which should be considered in the design of AOTF.

3.
J Org Chem ; 89(5): 3304-3308, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38356371

RESUMO

A protocol for the construction of an angular tricyclic benzofuran skeleton based on the C-H activation strategy has been established. Different phthalide lactones on this skeleton can be easily assembled with various side chains by using C-H activation with aldehydes and subsequent reduction. This skeleton provides a versatile and crucial motif for the total synthesis of naturally occurring angular tricyclic benzofurans and their derivatives. Based on this protocol, the improved total syntheses of daldinin A and annullatin D were achieved in yields of 17.3 and 7.6%, respectively.

4.
J Org Chem ; 89(11): 8011-8022, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38806442

RESUMO

We successfully developed an enantioselective trifluoromethylthiolation of structurally diverse carbonyl compounds. Trichloroisocyanuric acid and AgSCF3 were employed to generate active electrophilic trifluoromethylthio species in situ for asymmetric C-SCF3 bond formation. A broad variety of chiral SCF3-carbon nucleophiles (pyrazolones, ß-keto esters, and ß-keto amides) were obtained in excellent yields with high enantioselectivities (up to 92% ee) by Cinchona alkaloid derived squaramide catalysts. The reaction exhibits high efficiency, good enantioselectivity, and high functional group tolerance, which provided a novel and efficient way for asymmetric synthesis of trifluoromethylthiolated carbonyl compounds.

5.
Analyst ; 149(13): 3575-3584, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38758107

RESUMO

A restriction endonuclease (RE) is an enzyme that can recognize a specific DNA sequence and cleave that DNA into fragments with double-stranded breaks. This sequence-specific cleaving ability and its ease of use have made REs commonly used tools in molecular biology since their first isolation and characterization in 1970s. While artificial REs still face many challenges in large-scale synthesis and precise activity control for practical use, searching for new REs in natural samples remains a viable route to expanding the RE pool for fundamental research and industrial applications. In this paper, we propose a new strategy to search for REs in an efficient manner. We constructed a host bacterial cell to link the genotype of REs to the phenotype of ß-galactosidase expression based on the bacterial SOS response, and used a high-throughput microfluidic platform to isolate, detect and sort the REs in microfluidic drops at a frequency of ∼800 drops per second. We employed this strategy to screen for the XbaI gene from the constructed libraries of varied sizes. In a single round of sorting, a 90-fold target enrichment was achieved within 1 h. Compared to conventional RE-screening methods, the direct screening approach that we propose excels at efficient search of desirable REs in natural samples - especially unculturable samples - and can be tailored to high-throughput screening of a wide range of genotoxic targets.


Assuntos
Enzimas de Restrição do DNA , Escherichia coli , Resposta SOS em Genética , Escherichia coli/genética , Escherichia coli/enzimologia , Enzimas de Restrição do DNA/metabolismo , Ensaios de Triagem em Larga Escala/métodos , Técnicas Analíticas Microfluídicas/métodos , Técnicas Analíticas Microfluídicas/instrumentação , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Desoxirribonucleases de Sítio Específico do Tipo II/química , beta-Galactosidase/metabolismo , beta-Galactosidase/genética
6.
Angew Chem Int Ed Engl ; 63(1): e202316097, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37985423

RESUMO

Electrocatalytic nitrogen oxidation reaction (NOR) offers an efficient and sustainable approach for conversion of widespread nitrogen (N2 ) into high-value-added nitrate (NO3 - ) under mild conditions, representing a promising alternative to the traditional approach that involves harsh Haber-Bosch and Ostwald oxidation processes. Unfortunately, due to the weak absorption/activation of N2 and the competitive oxygen evolution reaction, the kinetics of NOR process is extremely sluggish accompanied with low Faradaic efficiencies and NO3 - yield rates. In this work, an oxygen-vacancy-enriched perovskite oxide with nonstoichiometric ratio of strontium and ruthenium (denoted as Sr0.9 RuO3 ) was synthesized and explored as NOR electrocatalyst, which can exhibit a high Faradaic efficiency (38.6 %) with a high NO3 - yield rate (17.9 µmol mg-1 h-1 ). The experimental results show that the amount of oxygen vacancies in Sr0.9 RuO3 is greatly higher than that of SrRuO3 , following the same trend as their NOR performance. Theoretical simulations unravel that the presence of oxygen vacancies in the Sr0.9 RuO3 can render a decreased thermodynamic barrier toward the oxidation of *N2 to *N2 OH at the rate-determining step, leading to its enhanced NOR performance.

7.
Small ; 19(5): e2205625, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36449575

RESUMO

Electrochemical nitrate reduction to ammonia (NRA) provides an efficient, sustainable approach to convert the nitrate pollutants into value-added products, which is regarded as a promising alternative to the industrial Haber-Bosch process. Recent studies have shown that oxygen vacancies of oxide catalysts can adjust the adsorption energies of intermediates and affect their catalytic performance. Compared with other metal oxides, perovskite oxides can allow their metal cations to exist in abnormal or mixed valence states, thereby resulting in enriched oxygen vacancies in their crystal structures. Here, the catalytic activities of perovskite oxides toward NRA catalysis with respect to the amount of oxygen vacancies are explored, where four perovskite oxides with different crystal structures (including cubic LaCrO3 , orthorhombic LaMnO3 and LaFeO3 , hexagonal LaCoO3 ) are chosen and investigated. By combining X-ray photoelectron spectroscopy, electron paramagnetic resonance spectroscopy and electrochemical measurements, it is found that the amount of oxygen vacancies in these perovskite oxides surprisingly follow the same order as their activities toward NRA catalysis (LaCrO3  < LaMnO3  < LaFeO3  < LaCoO3 ). Further theoretical studies reveal that the existence of oxygen vacancies in LaCoO3 perovskite can decrease the energy barriers for reduction of *HNO3 to *NO2 , leading to its superior NRA performance.

8.
Int J Med Microbiol ; 313(2): 151576, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36812841

RESUMO

INTRODUCTION: Pneumonia is an inflammation-related respiratory infection and chlorogenic acid (CGA) possesses a wide variety of bioactive properties, such as anti-inflammation and anti-bacteria. AIM: This study explored the anti-inflammatory mechanism of CGA in Klebsiella pneumoniae (Kp)-induced rats with severe pneumonia. METHODS: The pneumonia rat models were established by infection with Kp and treated with CGA. Survival rates, bacterial load, lung water content, and cell numbers in the bronchoalveolar lavage fluid were recorded, lung pathological changes were scored, and levels of inflammatory cytokines were determined by enzyme-linked immunosorbent assay. RLE6TN cells were infected with Kp and treated with CGA. The expression levels of microRNA (miR)-124-3p, p38, and mitogen-activated protein kinase (MAPK)-activated protein kinase 2 (MK2) in lung tissues and RLE6TN cells were quantified by real-time quantitative polymerase chain reaction or Western blotting. The binding of miR-124-3p to p38 was validated by the dual-luciferase and RNA pull-down assays. In vitro, the functional rescue experiments were performed using miR-124-3p inhibitor or p38 agonist. RESULTS: Kp-induced pneumonia rats presented high mortality, increased lung inflammatory infiltration and the release of inflammatory cytokines, and enhanced bacterial load, while CGA treatment improved rat survival rates and the above situations. CGA increased miR-124-3p expression, and miR-124-3p inhibited p38 expression and inactivated the p38MAPK pathway. Inhibition of miR-124-3p or activation of the p38MAPK pathway reversed the alleviative effect of CGA on pneumonia in vitro. CONCLUSION: CGA upregulated miR-124-3p expression and inactivated the p38MAPK pathway to downregulate inflammatory levels, facilitating the recovery of Kp-induced pneumonia rats.


Assuntos
MicroRNAs , Pneumonia , Ratos , Animais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/uso terapêutico , Klebsiella pneumoniae/genética , Ácido Clorogênico/farmacologia , Ácido Clorogênico/uso terapêutico , Klebsiella/genética , Klebsiella/metabolismo , MicroRNAs/genética , Pneumonia/tratamento farmacológico , Pneumonia/microbiologia , Citocinas/metabolismo , Anti-Inflamatórios/farmacologia
9.
Macromol Rapid Commun ; 44(7): e2200895, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36594347

RESUMO

Exploring the ring-opening polymerization (ROP) mechanism of benzoxazines is a fundamental issue in benzoxazine chemistry. Though some research papers on the topic have been reported, the ROP mechanism of mono-benzoxazines is still elusive. The key point for mechanistic studies is to determine and characterize the structure and formation pathways of the products generated in ROP. In this paper, the ROP of a vanillin-furfurylamine-based benzoxazine and a mono-azomethine derivative is studied with differential scanning calorimetry, fourier transform infrared spectroscopy, nuclear magnetic resonance, and electrospray ionization mass spectrometry, respectively. The results show that the products consist of a range of cationic species, zwitterions, fragments, and series of cyclic and linear oligomers of varying molecular sizes. It is proposed that both mono-benzoxazines undergo thermally activated cationic ring-opening oligomerization via zwitterion intermediates. Upon thermal induction, multi-bond-cleavage takes place to form various zwitterionic intermediates, which react with a monomer, a fragment, or a second zwitterion by several pathways to generate cyclic and linear oligomers.


Assuntos
Benzoxazinas , Furanos , Benzoxazinas/química , Polimerização
10.
Nucleic Acids Res ; 49(18): 10448-10464, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34570240

RESUMO

Histone H3 lysine 27 methylation catalyzed by polycomb repressive complex 2 (PRC2) is conserved from fungi to humans and represses gene transcription. However, the mechanism for recognition of methylated H3K27 remains unclear, especially in fungi. Here, we found that the bromo-adjacent homology (BAH)-plant homeodomain (PHD) domain containing protein BAH-PHD protein 1 (BP1) is a reader of H3K27 methylation in the cereal fungal pathogen Fusarium graminearum. BP1 interacts with the core PRC2 component Suz12 and directly binds methylated H3K27. BP1 is distributed in a subset of genomic regions marked by H3K27me3 and co-represses gene transcription. The BP1 deletion mutant shows identical phenotypes on mycelial growth and virulence, as well as similar expression profiles of secondary metabolite genes to the strain lacking the H3K27 methyltransferase Kmt6. More importantly, BP1 can directly bind DNA through its PHD finger, which might increase nucleosome residence and subsequently reinforce transcriptional repression in H3K27me3-marked target regions. A phylogenetic analysis showed that BP1 orthologs are mainly conserved in fungi. Overall, our findings provide novel insights into the mechanism by which PRC2 mediates gene repression in fungi, which is distinct from the PRC1-PRC2 system in plants and mammals.


Assuntos
Proteínas Fúngicas/metabolismo , Fusarium/genética , Regulação Fúngica da Expressão Gênica , Histonas/metabolismo , Complexo Repressor Polycomb 2/metabolismo , DNA/metabolismo , Proteínas Fúngicas/química , Fusarium/metabolismo , Histonas/química , Lisina/metabolismo , Proteínas Repressoras/metabolismo , Transcrição Gênica
11.
J Basic Microbiol ; 63(1): 92-103, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36316246

RESUMO

Hedgehog mushroom is a Hericium erinaceus associated with fagaceae and pinaceae trees in the northern hemisphere. It is still unknown whether this symbiotic relationship will affect the endophytic microbial community of the host plants. In this study, the endophytic microbial communities of different Quercus aliena tissues (root, stem, and leaf) with or without H. erinaceus partner were analyzed by bar-coded pyrosequencing. About 29,000 clean reads were obtained per sample representing 28 phyla of bacteria and 6 phyla of fungi. A total of 26,838 operational taxonomic units (OTUs) of bacteria and 4323 OTUs of fungi were observed at a 97% similarity level. Three bacterial phyla, Proteobacteria, Cyanobacteria and Bacteroidetes, and fungal phylum Ascomycota were dominant in all tissues. The relative abundance of these dominant communities showed significantly differences between Q. aliena tissues with or without H. erinaceus. Bacterial genus Pseudomonas and fungal genus Cryptosporiopsis were species-rich in Q. aliena root infected by H. erinaceus hyphae. This study demonstrated that the endophytic microbial community structure and dominant species varied in Q. aliena mycorrhized with H. erinaceus.


Assuntos
Agaricales , Ascomicetos , Cianobactérias , Microbiota , Animais , Ouriços , Endófitos/genética , Raízes de Plantas/microbiologia
12.
Bioorg Med Chem ; 73: 117033, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36202064

RESUMO

Targeted protein degradation using proteolysis-targeting chimeras (PROTACs) has emerged as an effective strategy for drug discovery, given their unique advantages over target protein inhibition. The bromodomain and extra-terminal (BET) family proteins play a key role in regulating oncogene expression and are considered attractive therapeutic targets for cancer therapy. Considering the therapeutic potential of BET proteins in cancer and the marked attractiveness of PROTACs, BET-targeting PROTACs have been extensively pursued. Recently, BET-targeting PROTACs based on new E3 ligases and novel strategies, such as light-activated, macrocyclic, folate-caged, aptamer-PROTAC conjugation, antibody-coupling, and autophagy-targeting strategies, have emerged. In the present review, we provide a comprehensive summary of advances in BET-targeting PROTACs.


Assuntos
Neoplasias , Humanos , Ácido Fólico , Neoplasias/tratamento farmacológico , Proteólise , Ubiquitina-Proteína Ligases/metabolismo
13.
Arch Toxicol ; 96(6): 1751-1766, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35384471

RESUMO

Approximately 70-90% of mushroom poisoning deaths are caused by α-amanitin-induced liver injury resulting from RNA polymerase II (RNAP II) inhibition. Liver regeneration ability may contribute greatly to individual survival after α-amanitin poisoning. However, it is unclear what cellular pathways are activated to stimulate regeneration. We conducted dose-effect and time-effect studies in mice that were intraperitoneally injected with 0.33-0.66 mg/kg α-amanitin to establish a poisoning model. The liver/body weight ratio, serological indices, and pathology were evaluated to characterize the liver injury. In the time-effect study, the liver transcriptome was analyzed to explore the mRNA changes resulting from RNAP II inhibition and the underlying pathways associated with recovery. Based on the two animal studies, we established a poisoning model with three sequential liver states: early injury, regulation, and recovery. The mRNA changes reflected by the differentially expressed genes (DEGs) in the transcriptome could be used to illustrate the inhibition of RNAP II by α-amanitin. DEGs at four key time points were well matched with the three liver states, including 8-h downregulated genes in the early injury state, 16-h and 72-h upregulated genes in the regulation state, and 96-h upregulated/downregulated genes in the recovery state. By clustering analysis, the mTOR signaling pathway was screened out as the most promising potential pathway promoting recovery. The results of our investigations of the pathways and events downstream of the mTOR pathway indicated that the activation of mTOR probably contributes crucially to liver regeneration, which could be a promising basis for drug development.


Assuntos
Agaricales , Alfa-Amanitina , Fígado , Intoxicação Alimentar por Cogumelos , Transcriptoma , Alfa-Amanitina/intoxicação , Animais , Perfilação da Expressão Gênica , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Intoxicação Alimentar por Cogumelos/metabolismo , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Serina-Treonina Quinases TOR/metabolismo
14.
Appl Opt ; 61(12): 3419-3428, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35471438

RESUMO

The soluble solids content (SSC) is an important factor in the internal quality detection of apples. It is essential to have reliable and high-speed measurement of the SSC. However, almost all traditional equipment is inconvenient and expensive. We designed a handheld nondestructive SSC detector based on near-infrared (NIR) spectroscopy, which is composed of a portable NIR spectrometer, cloud server, smartphone app, and prediction model of SSC. We preprocessed the spectrum with multiplicative scatter correction (MSC), standard normal variable transformation (SNV), and Savitzky-Golay (S-G) smoothing algorithms. Besides, the linear weight reduction of the particle swarm optimization algorithm is carried out, and we establish the model of an extreme learning machine optimized with the improved particle swarm optimization (IPSO-ELM) algorithm. The R2, root mean square error of prediction (RMSEP), and residual prediction deviation (RPD) of the model are 0.993, 0.0155, and 11.6, respectively, which are better than the traditional model obviously. In addition, the number of wavelengths reduced from 228 to 70 as the model is simplified with the uninformative variable elimination (UVE) method. The time of training is reduced by 29.30% compared with the original spectrum. It can be verified that the IPSO-ELM model has good prediction performance, and the NIR diffuse reflectance spectroscopy is a reliable nondestructive measurement of SSC in apples.


Assuntos
Malus , Algoritmos , Análise dos Mínimos Quadrados , Refratometria , Espectroscopia de Luz Próxima ao Infravermelho/métodos
15.
Br J Anaesth ; 127(1): 56-64, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33685636

RESUMO

BACKGROUND: Although sedation during gastrointestinal endoscopy is widely used in China, the characteristics of sedation use, including regional distribution, personnel composition, equipment used, and drug selection, remain unclear. The present study aimed to provide insights into the current practice and regional distribution of sedation for gastrointestinal endoscopy in China. METHODS: A questionnaire consisting of 19 items was distributed to directors of anaesthesiology departments and anaesthesiologists in charge of endoscopic sedation units in mainland China through WeChat. RESULTS: The results from 2758 participating hospitals (36.7% of the total) showed that 9 808 182 gastroscopies (69.3%) and 4 353 950 colonoscopies (30.7%), with a gastroscopy-to-colonoscopy ratio of 2.3, were conducted from January to December 2016. Sedation was used with 4 696 648 gastroscopies (47.9%) and 2 148 316 colonoscopies (49.3%), for a ratio of 2.2. The most commonly used sedative was propofol (61.0% for gastroscopies and 60.4% for colonoscopies). Haemoglobin oxygen saturation (SpO2) was monitored in most patients (96.1%). Supplemental oxygen was routinely administered, but the availability of other equipment was variable (anaesthesia machine in 64.9%, physiological monitor in 84.4%, suction device in 72.3%, airway equipment in 75.5%, defibrillator in 32.7%, emergency kit in 57.0%, and difficult airway kit in 20.8% of centres responding). CONCLUSIONS: The sedation rate for gastrointestinal endoscopy is much lower in China than in the USA and in Europe. The most commonly used combination of sedatives was propofol plus an opioid (either fentanyl or sufentanil). Emergency support devices, such as difficult airway devices and defibrillators, were not usually available.


Assuntos
Anestesia/métodos , Endoscopia Gastrointestinal/métodos , Endoscopia Gastrointestinal/tendências , Pessoal de Saúde/tendências , Hospitais/tendências , Inquéritos e Questionários , Analgésicos Opioides/administração & dosagem , Anestésicos Intravenosos/administração & dosagem , China/epidemiologia , Humanos , Projetos Piloto , Estudos Retrospectivos
16.
J Integr Plant Biol ; 63(4): 707-722, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33438356

RESUMO

Heterochromatin is widespread in eukaryotic genomes and has diverse impacts depending on its genomic context. Previous studies have shown that a protein complex, the ASI1-AIPP1-EDM2 (AAE) complex, participates in polyadenylation regulation of several intronic heterochromatin-containing genes. However, the genome-wide functions of AAE are still unknown. Here, we show that the ASI1 and EDM2 mostly target the common genomic regions on a genome-wide level and preferentially interacts with genetic heterochromatin. Polyadenylation (poly(A) sequencing reveals that AAE complex has a substantial influence on poly(A) site usage of heterochromatin-containing genes, including not only intronic heterochromatin-containing genes but also the genes showing overlap with heterochromatin. Intriguingly, AAE is also involved in the alternative splicing regulation of a number of heterochromatin-overlapping genes, such as the disease resistance gene RPP4. We provided evidence that genic heterochromatin is indispensable for the recruitment of AAE in polyadenylation and splicing regulation. In addition to conferring RNA processing regulation at genic heterochromatin-containing genes, AAE also targets some transposable elements (TEs) outside of genes (including TEs sandwiched by genes and island TEs) for epigenetic silencing. Our results reveal new functions of AAE in RNA processing and epigenetic silencing, and thus represent important advances in epigenetic regulation.


Assuntos
Epigênese Genética/genética , Processamento Alternativo/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Elementos de DNA Transponíveis/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Heterocromatina/genética , Poliadenilação/genética , Poliadenilação/fisiologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Cell Commun Signal ; 18(1): 135, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32843056

RESUMO

BACKGROUND: Glioma stem cells (GSCs) are glioma cells with stemness and are responsible for a variety of malignant behaviors of glioma. Evidence has shown that signals from tumor microenvironment (TME) enhance stemness of glioma cells. However, identification of the signaling molecules and underlying mechanisms has not been completely elucidated. METHODS: Human samples and glioma cell lines were cultured in vitro to determine the effects of adenovirus (ADV) infection by sphere formation, RT-qPCR, western blotting, FACS and immunofluorescence. For in vivo analysis, mouse intracranial tumor model was applied. Bioinformatics analysis, gene knockdown by siRNA, RT-qPCR and western blotting were applied for further mechanistic studies. RESULTS: Infection of patient-derived glioma cells with ADV increases the formation of tumor spheres. ADV infection upregulated stem cell markers and in turn promoted the capacities of self-renewal and multi-lineage differentiation of the infected tumor spheres. These ADV infected tumor spheres had stronger potential to form xenograft tumors in immune-compromised mice. GSCs formation could be promoted by ADV infection via TLR9, because TLR9 was upregulated after ADV infection, and knockdown of TLR9 reduced ADV-induced GSCs. Consistently, MYD88, as well as total STAT3 and phosphorylated (p-)STAT3, were also upregulated in ADV-induced GSCs. Knockdown of MYD88 or pharmaceutical inhibition of STAT3 attenuated stemness of ADV-induced GSCs. Moreover, we found that ADV infection upregulated lncRNA NEAT1. Knockdown of NEAT1 impaired stemness of ADV-induced GSCs. Lastly, HMGB1, a damage associated molecular pattern (DAMP) that triggers TLR signaling, also upregulated stemness markers in glioma cells. CONCLUSION: ADV, which has been developed as vectors for gene therapy and oncolytic virus, promotes the formation of GSCs via TLR9/NEAT1/STAT3 signaling. Video abstract.


Assuntos
Infecções por Adenoviridae/complicações , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Células-Tronco Neoplásicas/patologia , RNA Longo não Codificante/metabolismo , Fator de Transcrição STAT3/metabolismo , Receptor Toll-Like 9/metabolismo , Animais , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Transformação Celular Neoplásica/patologia , Regulação Neoplásica da Expressão Gênica , Proteína HMGB1/metabolismo , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fator 88 de Diferenciação Mieloide/metabolismo , Células-Tronco Neoplásicas/metabolismo , RNA Longo não Codificante/genética , Transdução de Sinais , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia
18.
Proc Natl Acad Sci U S A ; 114(47): 12590-12595, 2017 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-29114054

RESUMO

Some microbes possess the ability to adaptively manipulate host behavior. To better understand how such microbial parasites control animal behavior, we examine the cell-level interactions between the species-specific fungal parasite Ophiocordyceps unilateralis sensu lato and its carpenter ant host (Camponotus castaneus) at a crucial moment in the parasite's lifecycle: when the manipulated host fixes itself permanently to a substrate by its mandibles. The fungus is known to secrete tissue-specific metabolites and cause changes in host gene expression as well as atrophy in the mandible muscles of its ant host, but it is unknown how the fungus coordinates these effects to manipulate its host's behavior. In this study, we combine techniques in serial block-face scanning-electron microscopy and deep-learning-based image segmentation algorithms to visualize the distribution, abundance, and interactions of this fungus inside the body of its manipulated host. Fungal cells were found throughout the host body but not in the brain, implying that behavioral control of the animal body by this microbe occurs peripherally. Additionally, fungal cells invaded host muscle fibers and joined together to form networks that encircled the muscles. These networks may represent a collective foraging behavior of this parasite, which may in turn facilitate host manipulation.


Assuntos
Formigas/microbiologia , Interações Hospedeiro-Patógeno , Hypocreales/ultraestrutura , Aprendizado de Máquina , Músculos/microbiologia , Animais , Formigas/anatomia & histologia , Formigas/citologia , Comportamento Animal , Hypocreales/patogenicidade , Hypocreales/fisiologia , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Imageamento Tridimensional , Mandíbula/microbiologia , Músculos/ultraestrutura
19.
Ecotoxicol Environ Saf ; 200: 110747, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32460052

RESUMO

The presence of surfactants may affect the bioavailability of polycyclic aromatic hydrocarbons. A hydroponic experiment was conducted to investigate the response of Hydrocharis dubia (Bl.) Backer to different concentrations of linear alkylbenzene sulfonate (LAS), naphthalene (NAP) and their mixture (0.5, 5, 10, and 20 mg/L) for 14 days and 28 days. The results showed that LAS had a greater toxic effect on H. dubia growth than NAP at treatment concentrations of 0.5-20 mg/L. The combined effect of LAS and NAP was damaging to H. dubia at concentrations of LAS + NAP ≥5 + 5 mg/L. When LAS + NAP ≥10 + 10 mg/L, the underground parts of H. dubia suffered more significant damage than the aboveground parts. Under the treatments with LAS, NAP and their mixture, H. dubia experienced oxidative stress. Soluble proteins and antioxidant enzymes were the main substances protecting H. dubia from LAS stress, and superoxide dismutase (SOD) and peroxidase (POD) were the main protective enzymes. When exposed to NAP, H. dubia growth was stimulated and promoted at the same time. In the short-term treatment (14 d), catalase (CAT) activity was sensitive to NAP stimulation, and soluble proteins and SOD were the main protective substances produced. Soluble sugars, SOD and ascorbate peroxidase (APX) played important protective roles during the longer exposure time (28 d). The physiological response of H. dubia exposed to the combined toxicants was weaker than the response to exposure to individual toxicants. The responses of SOD and CAT activity were positive in the short term (14 d), and these were the main protective enzymes. As the exposure time increased (28 d), the plant antioxidant system responded negatively.


Assuntos
Ácidos Alcanossulfônicos/toxicidade , Hydrocharitaceae/efeitos dos fármacos , Naftalenos/toxicidade , Tensoativos/toxicidade , Ácidos Alcanossulfônicos/antagonistas & inibidores , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Sinergismo Farmacológico , Hydrocharitaceae/enzimologia , Hydrocharitaceae/metabolismo , Naftalenos/antagonistas & inibidores , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Superóxido Dismutase/metabolismo
20.
Biochem Biophys Res Commun ; 514(1): 205-209, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31029418

RESUMO

The mechanisms of cell turnover including cell proliferation and cell differentiation were complex. Planarians possess amazing regeneration ability and undergo cell turnover throughout life. We identified a homologous gene of ERas by RNAi in Dugesia japonica. Knocking-down DjERas resulted in regeneration and homeostasis defects. Furthermore, we found that the expression of neoblasts and late progeny marker gene decreased in DjERas RNAi planarians. Our studies indicated that down-regulation of DjERas inhibited the proliferation and differentiation of stem cells through the conserved signaling pathway, resulted in the inability of the planarian to regenerate and maintain homeostasis. Our results suggest that DjERas plays a crucial role in the process of cell turnover.


Assuntos
Planárias/fisiologia , Regeneração/fisiologia , Proteínas ras/genética , Animais , Regulação da Expressão Gênica , Marcadores Genéticos , Homeostase/fisiologia , Planárias/citologia , Interferência de RNA , Proteínas ras/metabolismo
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