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1.
J Cell Mol Med ; 28(1): e18021, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37994489

RESUMO

Clinical assessments relying on pathology classification demonstrate limited effectiveness in predicting clinical outcomes and providing optimal treatment for patients with ovarian cancer (OV). Consequently, there is an urgent requirement for an ideal biomarker to facilitate precision medicine. To address this issue, we selected 15 multicentre cohorts, comprising 12 OV cohorts and 3 immunotherapy cohorts. Initially, we identified a set of robust prognostic risk genes using data from the 12 OV cohorts. Subsequently, we employed a consensus cluster analysis to identify distinct clusters based on the expression profiles of the risk genes. Finally, a machine learning-derived prognostic signature (MLDPS) was developed based on differentially expressed genes and univariate Cox regression genes between the clusters by using 10 machine-learning algorithms (101 combinations). Patients with high MLDPS had unfavourable survival rates and have good prediction performance in all cohorts and in-house cohorts. The MLDPS exhibited robust and dramatically superior capability than 21 published signatures. Of note, low MLDIS have a positive prognostic impact on patients treated with anti-PD-1 immunotherapy by driving changes in the level of infiltration of immune cells. Additionally, patients suffering from OV with low MLDIS were more sensitive to immunotherapy. Meanwhile, patients with low MLDIS might benefit from chemotherapy, and 19 compounds that may be potential agents for patients with low MLDIS were identified. MLDIS presents an appealing instrument for the identification of patients at high/low risk. This could enhance the precision treatment, ultimately guiding the clinical management of OV.


Assuntos
Neoplasias Ovarianas , Humanos , Feminino , Prognóstico , Imunoterapia , Algoritmos , Aprendizado de Máquina , Microambiente Tumoral
2.
Molecules ; 29(15)2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39124964

RESUMO

An efficient and operationally simple method for the synthesis of ß-keto sulfones through the BF3·OEt2-promoted reaction of alkynes and sodium sulfinates is developed. With its facile and selective access to the targets, it features good functional group compatibility, mild conditions, easily available starting materials, and good yields. Notably, the reaction does not require metal catalysts or chemical reagents with pungent odors.

3.
Bioorg Chem ; 141: 106838, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37717414

RESUMO

Six pyrazolopyrimidine rhodium(III) or palladium(II) complexes, [Rh(L1)(H2O)Cl3] (1), [Rh(L2)(CH3OH)Cl3] (2), [Rh(L3)(H2O)Cl3] (3), [Rh2(L4)Cl6]·CH3OH (4), [Rh(L5)(CH3CN)Cl3]·0.5CH3CN (5), and [Pd(L5)Cl2] (6), were synthesized and characterized. These complexes showed high cytotoxicity against six tested cancer cell lines. Most of the complexes showed higher cytotoxicity to T-24 cells in vitro than cisplatin. Mechanism studies indicated that complexes 5 and 6 induced G2/M phase cell cycle arrest through DNA damage, and induced apoptosis via endoplasmic reticulum stress response. In addition, complex 5 also induced cell apoptosis via mitochondrial dysfunction. Complexes 5 and 6 showed low in vivo toxicity and high tumor growth inhibitory activity in mouse tumor models. The inhibitory effect of rhodium complex 5 on tumor growth in vivo was more pronounced than that of palladium complex 6.


Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias , Ródio , Animais , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo , Ródio/farmacologia , Paládio/farmacologia , Linhagem Celular , Neoplasias/tratamento farmacológico , Apoptose , Complexos de Coordenação/farmacologia , Linhagem Celular Tumoral
4.
BMC Womens Health ; 23(1): 555, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884919

RESUMO

OBJECTIVE: This study aimed to explore metabolic abnormalities in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) for metabolism-related genes. METHODS: We downloaded expression data for metabolism-related genes, performed differential expression analysis, and applied weighted gene co-expression network analysis (WGCNA) to identify metabolism-related functional modules. We obtained normalised miRNA expression data and identified master methylation regulators for metabolism-related genes. Cox regression of data on metabolism-related genes was performed to screen for genes that affect the prognosis of patients with CESC. Furthermore, we selected key genes for validation. RESULTS: Our results identified 3620 metabolism-related genes in CESC, 2493 of which contained related mutations. The co-occurrence of CUBN, KALRN, and HERC1 was related to the prognosis of CESC. The fraction of genome altered (FGA) closely correlated with overall survival. In expression analysis, 374 genes were related to the occurrence and prognosis of CESC. We then identified four metabolic pathway modules in WGCNA. Further analysis revealed that glycolysis/gluconeogenesis was related to endothelial cells and that arachidonic acid metabolism was related to cell proliferation. These four modules were also related to the prognosis of CESC. Among CESC-related metabolic genes, two genes were found to be regulated by microRNAs (miRNAs) and methylation, whereas another two genes were coregulated by miRNAs and mutations. CONCLUSIONS: Among metabolism-related genes, 15 genes were related to the prognosis of CESC. The co-occurrence of CUBN/KALRN/HERC1 was associated with CESC prognosis. Glycolysis/gluconeogenesis was related to endothelial cells, and arachidonic acid metabolism was related to cell proliferation.


Assuntos
Carcinoma de Células Escamosas , MicroRNAs , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/genética , Ácido Araquidônico , Células Endoteliais , MicroRNAs/genética , Prognóstico
5.
Molecules ; 28(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37570605

RESUMO

Organic thioethers play an important role in the discovery of drugs and natural products. However, the green synthesis of organic sulfide compounds remains a challenging task. The convenient and efficient synthesis of 5-alkoxy-3-halo-4-methylthio-2(5H)-furanones from DMSO is performed via the mediation of 1,3-dibromo-5,5-dimethylhydantoin (DBDMH), affording a facile route for the sulfur-functionalization of 3,4-dihalo-2(5H)-furanones under transition metal-free conditions. This new approach has demonstrated the functionalization of non-aromatic Csp2-X-type halides with unique structures containing C-X, C-O, C=O and C=C bonds. Compared with traditional synthesis methods using transition metal catalysts with ligands, this reaction has many advantages, such as the lower temperature, the shorter reaction time, the wide substrate range and good functional group tolerance. Notably, DMSO plays multiple roles, and is simultaneously used as an odorless methylthiolating reagent and safe solvent.

6.
J Integr Plant Biol ; 65(6): 1536-1552, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37073786

RESUMO

Although root nodules are essential for biological nitrogen fixation in legumes, the cell types and molecular regulatory mechanisms contributing to nodule development and nitrogen fixation in determinate nodule legumes, such as soybean (Glycine max), remain incompletely understood. Here, we generated a single-nucleus resolution transcriptomic atlas of soybean roots and nodules at 14 days post inoculation (dpi) and annotated 17 major cell types, including six that are specific to nodules. We identified the specific cell types responsible for each step in the ureides synthesis pathway, which enables spatial compartmentalization of biochemical reactions during soybean nitrogen fixation. By utilizing RNA velocity analysis, we reconstructed the differentiation dynamics of soybean nodules, which differs from those of indeterminate nodules in Medicago truncatula. Moreover, we identified several putative regulators of soybean nodulation and two of these genes, GmbHLH93 and GmSCL1, were as-yet uncharacterized in soybean. Overexpression of each gene in soybean hairy root systems validated their respective roles in nodulation. Notably, enrichment for cytokinin-related genes in soybean nodules led to identification of the cytokinin receptor, GmCRE1, as a prominent component of the nodulation pathway. GmCRE1 knockout in soybean resulted in a striking nodule phenotype with decreased nitrogen fixation zone and depletion of leghemoglobins, accompanied by downregulation of nodule-specific gene expression, as well as almost complete abrogation of biological nitrogen fixation. In summary, this study provides a comprehensive perspective of the cellular landscape during soybean nodulation, shedding light on the underlying metabolic and developmental mechanisms of soybean nodule formation.


Assuntos
Ascomicetos , Medicago truncatula , Fixação de Nitrogênio/genética , Glycine max/fisiologia , Nodulação/genética , Nódulos Radiculares de Plantas/genética , Nódulos Radiculares de Plantas/metabolismo , Transcriptoma/genética , Citocininas/metabolismo , Medicago truncatula/genética , Medicago truncatula/metabolismo , Simbiose/genética , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nitrogênio/metabolismo
7.
Nanotechnology ; 33(15)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-34952533

RESUMO

Voltage-driven stochastic magnetization switching in a nanomagnet has attracted more attention recently with its superiority in achieving energy-efficient artificial neuron. Here, a novel pure voltage-driven scheme with ∼27.66 aJ energy dissipation is proposed, which could rotate magnetization vector randomly using only a pair of electrodes covered on the multiferroic nanomagnet. Results show that the probability of 180° magnetization switching is examined as a sigmoid-like function of the voltage pulse width and magnitude, which can be utilized as the activation function of designed neuron. Considering the size errors of designed neuron in fabrication, it's found that reasonable thickness and width variations cause little effect on recognition accuracy for MNIST hand-written dataset. In other words, the designed pure voltage-driven spintronic neuron could tolerate size errors. These results open a new way toward the realization of artificial neural network with low power consumption and high reliability.

8.
Planta ; 253(5): 109, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33871705

RESUMO

MAIN CONCLUSION: QTL mapping of stem diameter was carried out in three RIL populations using a high-density genetic map, and candidate genes related to stem diameter were predicted. Stem diameter is an important agronomic trait affecting soybean lodging and productivity. However, this trait is underexploited, and the underlying genetic mechanism in soybean remains unclear. In this study, three recombinant inbred line (RIL) populations, including 156 F10 lines from Nannong 94-156 × Bogao (N × B), 127 F9 lines from Dongnong 50 × Williams 82 (D × W), and 146 F9 lines from Suinong 14 × Enrei (S × E), were used to identify QTLs for soybean stem diameter across multiple environments. Phenotype analysis revealed that stem diameter exhibited strong positive correlations with plant height and 100-seed weight, two of the most important yield components. A total of 12 QTLs for stem diameter were identified on eight chromosomes across three RIL populations and five environments. The most influential QTL that was stably identified across all the populations and environments, q11, explained 12.58-26.63% of the phenotypic variation. Detection of several environment-specific QTLs, including q14, q16, and q20, suggests that environments may also have important effects in shaping the natural variation in soybean stem diameter. Furthermore, we predicted candidate genes underlying the QTLs and found that several promising candidate genes may be responsible for the variation in stem diameter in soybean. Overall, the markers/genes linked closely or underlying the major QTLs may be used for marker-assisted selection of soybean varieties to enhance lodging resistance and even yield. Our results lay the foundation for the fine mapping of stem development-related genes to reveal the molecular mechanisms.


Assuntos
Glycine max , Locos de Características Quantitativas , Mapeamento Cromossômico , Ligação Genética , Fenótipo , Locos de Características Quantitativas/genética , Sementes , Glycine max/genética
9.
J Obstet Gynaecol Res ; 47(7): 2394-2405, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33949053

RESUMO

AIM: Endometriosis is a common gynecological disorder characterized by chronic pelvic pain and infertility, which negatively affects women's health worldwide. AFAP1-AS1 has been implicated in endometriosis lesions recently, but its mechanism of endometriosis progression remains unclear. METHODS: Endometrial stromal cells (ESCs) were used to identify the role of AFAP1-AS1 in endometriosis. The migratory capability was determined by transwell. Gene and protein expressions were identified by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. Cell viability and apoptosis were detected by MTT assays and flow cytometry, respectively. Luciferase report assays were used to identify the interaction of AFAP1-AS1, miR-424-5p and signal transducer and activator of transcription 3 (STAT3). RESULTS: AFAP1-AS1 knockdown or miR-424-5p overexpression inhibited proliferation and migration, and promoted apoptosis in ESCs. In addition, knockdown of AFAP1-AS1 repressed the expression of ki-67 and Bcl-2, and promoted the levels of cleaved caspase-3 and Bax. Furthermore, knockdown of AFAP1-AS1 inhibited the conversion of E-cadherin to N-cadherin and the expression of Snail. Moreover, AFAP1-AS1 activated the STAT3/transforming growth factor-ß1 (TGF-ß1)/Smad2 axis via directly targeting miR-424-5p. The regulatory effect of AFAP1-AS1 silencing in ESC migration, proliferation, and apoptosis was reversed by miR-424-5p inhibition or STAT3 overexpression. CONCLUSIONS: AFAP1-AS1 silencing could inhibit cell proliferation and promote apoptosis by regulating STAT3/TGF-ß/Smad signaling pathway via targeting miR-424-5p in ESCs. AFAP1-AS1 may be a potential therapeutic target of controlling the progression of endometriosis.


Assuntos
Endometriose , MicroRNAs , RNA Longo não Codificante , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Fator de Transcrição STAT3 , Transdução de Sinais , Fator de Crescimento Transformador beta
10.
Hemoglobin ; 45(5): 329-331, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34957901

RESUMO

Homozygous or compound heterozygous mutations of the ß-globin gene lead to ß-thalassemia (ß-thal) major (ß-TM) or ß-thal intermedia (ß-TI), whereas heterozygotes usually show microcytosis with negligible or no hemolysis. Certain missense mutations in exon 3, however, produce unstable globins causing a dominant ß-thal phenotype or hemolytic anemia in heterozygotes. Here we report a mutation in exon 3 of the ß-globin gene, which results in an unstable globin (Hb Dieppe) [ß127(H5)Gln→Arg; HBB: c.383A>G] with a dominant ß-thal phenotype in two generations of a Chinese family. Physicians should be alerted to this mechanism of ß-thal considering its relative rarity.


Assuntos
Talassemia beta , Éxons , Humanos , Mutação , Fenótipo , Globinas beta/genética , Talassemia beta/diagnóstico , Talassemia beta/genética
11.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(2): 194-201, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33829691

RESUMO

OBJECTIVE: To construct eukaryotic and prokaryotic recombinant vectors containing Pepck- Gp63 and to achieve protein expression by selecting the dominant epitope genes of Pepck and Gp63 of Leishmania infantum. METHODS: The secondary structure and HLA epitopes of phosphoenolpyruvate carboxylase (PEPCK) were predicted by in silico analysis, and the dominant epitopes were picked out. According to the analysis results of glycoprotein of 63×10 3(GP63) epitopes identified by the same method in our laboratory, the dominant epitope genes of Pepck and Gp63 were used to construct pET32a- Pepck- Gp63 and pVAX1- Pepck- Gp63 by overlapping PCR and enzyme reaction. Then, for protein expression, the prokaryotic vectors were transfected into E.coil while the eukaryotic vectors were transfected into NIH3T3 cells by liposome transfection. RESULTS: There were multiple dominant epitopes in Pepckand there were Pepck-Gp63 sequences in the polyclonal site of expression vector. The expression of Pepck-Gp63 in E.coil appeared in inclusion form and led to 74 kDa band in SDS-PAGE. The immunofluorescence results of NIH3T3 cells transfected by pVAX1- Pepck-Gp63 were positive. CONCLUSION: The recombinant prokaryotic expression plasmids pET32a- Pepck-Gp63 and eukaryotic expression plasmids pVAX1- P epck -Gp63 were successfully constructed, and it was shown that the recombinant plasmids were able to express the corresponding target proteins in E. coli and NIH3T3 cells, respectively, providing a preliminary experimental basis for the subsequent study of immunization strategies.


Assuntos
Leishmania infantum , Animais , Epitopos/genética , Escherichia coli/genética , Eucariotos , Vetores Genéticos/genética , Leishmania infantum/genética , Camundongos , Células NIH 3T3 , Fosfoenolpiruvato Carboxilase , Plasmídeos
12.
Genome Res ; 27(9): 1525-1535, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28684554

RESUMO

Translational efficiency is subject to extensive regulation. However, the factors influencing such regulation are poorly understood. In Caenorhabditis elegans, 62% of genes are trans-spliced to a specific spliced leader (SL1), which replaces part of the native 5' untranslated region (5' UTR). Given the pivotal role the 5' UTR plays in the regulation of translational efficiency, we hypothesized that SL1 trans-splicing functions to regulate translational efficiency. With genome-wide analysis on Ribo-seq data, polysome profiling experiments, and CRISPR-Cas9-based genetic manipulation of trans-splicing sites, we found four lines of evidence in support of this hypothesis. First, SL1 trans-spliced genes have higher translational efficiencies than non-trans-spliced genes. Second, SL1 trans-spliced genes have higher translational efficiencies than non-trans-spliced orthologous genes in other nematode species. Third, an SL1 trans-spliced isoform has higher translational efficiency than the non-trans-spliced isoform of the same gene. Fourth, deletion of trans-splicing sites of endogenous genes leads to reduced translational efficiency. Importantly, we demonstrated that SL1 trans-splicing plays a key role in enhancing translational efficiencies of essential genes. We further discovered that SL1 trans-splicing likely enhances translational efficiency by shortening the native 5' UTRs, hence reducing the presence of upstream start codons (uAUG) and weakening mRNA secondary structures. Taken together, our study elucidates the global function of trans-splicing in enhancing translational efficiency in nematodes, paving the way for further understanding the genomic mechanisms of translational regulation.


Assuntos
Proteínas Pol1 do Complexo de Iniciação de Transcrição/genética , Biossíntese de Proteínas , RNA Mensageiro/genética , Trans-Splicing/genética , Regiões 5' não Traduzidas/genética , Animais , Sistemas CRISPR-Cas/genética , Caenorhabditis elegans/genética , Códon de Iniciação/genética , Edição de Genes , Genoma/genética , Splicing de RNA/genética , RNA Mensageiro/biossíntese
13.
J Org Chem ; 85(2): 1168-1180, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31878775

RESUMO

A novel protocol for the efficient preparation of α-hydroxy allylic thioesters via a Lewis base-catalyzed tandem isomerization/allylic alkylation process is reported. The resulting allylic thioesters can serve as valuable scaffolds to undergo a stereoselective intramolecular cyclization to deliver 2,7-dioxabicyclo[2.2.1]heptan-3-one derivatives in a catalytically atom-economic fashion.

14.
Mol Biol Evol ; 34(11): 2944-2958, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28961875

RESUMO

Codon usage bias (CUB) refers to the observation that synonymous codons are not used equally frequently in a genome. CUB is stronger in more highly expressed genes, a phenomenon commonly explained by stronger natural selection on translational accuracy and/or efficiency among these genes. Nevertheless, this phenomenon could also occur if CUB regulates gene expression at the mRNA level, a hypothesis that has not been tested until recently. Here, we attempt to quantify the impact of synonymous mutations on mRNA level in yeast using 3,556 synonymous variants of a heterologous gene encoding green fluorescent protein (GFP) and 523 synonymous variants of an endogenous gene TDH3. We found that mRNA level was positively correlated with CUB among these synonymous variants, demonstrating a direct role of CUB in regulating transcript concentration, likely via regulating mRNA degradation rate, as our additional experiments suggested. More importantly, we quantified the effects of individual synonymous mutations on mRNA level and found them dependent on 1) CUB and 2) mRNA secondary structure, both in proximal sequence contexts. Our study reveals the pleiotropic effects of synonymous codon usage and provides an additional explanation for the well-known correlation between CUB and gene expression level.


Assuntos
Códon/genética , RNA Mensageiro/genética , Mutação Silenciosa/genética , Evolução Molecular , Regulação da Expressão Gênica/genética , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Proteínas de Fluorescência Verde/genética , Modelos Genéticos , Mutação , Biossíntese de Proteínas/genética , Estabilidade de RNA/genética , Proteínas de Saccharomyces cerevisiae/genética , Seleção Genética/genética
15.
New Phytol ; 219(4): 1373-1387, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30063801

RESUMO

Vernalization, the requirement of plants for long-term exposure to low environmental temperature for flowering, is an epigenetic phenomenon. Histone modification regulation has been revealed in vernalization, but is limited to key genes. Now, we know that VRN1 is epigenetically critical for monocots. Genome-wide analysis is still unavailable, however. We performed chromatin immunoprecipitation-sequencing for H3K4me3/H3K27me3 in Brachypodium distachyon to obtain a global view of histone modifications in vernalization on a genome-wide scale and for different pathways/genes. Our data showed that H3K4me3 and H3K27me3 play distinct roles in vernalization. Unlike H3K4me3, H3K27me3 exhibited regional regulation, showed main regulation targets in vernalization and contributed to epigenetic memory. For genes in four flowering regulation pathways, only FT2 (functional ortholog of VRN3 in B. distachyon) and VRN1 showed coordinated changes in H3K4me3/H3K27me3. The epigenetic response at VRN3 was weaker under short-day than under long-day conditions. VRN3 was revealed as an epigenetic regulation point integrating vernalization and day length signals. We globally identified genes maintaining vernalization-induced epigenetic changes. Most of these genes showed dose-dependent vernalization responses, revealing a quantitative 'recording system' for vernalization. Our studies shed light on the epigenetic role of VRN3 and H3K4me3/H3K27me3 in vernalization and reveal genes underlying epigenetic memory, laying the foundation for further study.


Assuntos
Brachypodium/genética , Epigênese Genética , Flores/genética , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Histonas/metabolismo , Proteínas de Plantas/metabolismo , Genes de Plantas , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/metabolismo , Proteínas de Plantas/genética
16.
Phytother Res ; 32(10): 2047-2058, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30024074

RESUMO

Oxymatrine (OXY) has antioxidative and antiinflammatory activities. In the present work, we investigate the effects of OXY on gastric ulcer models and elucidate the underlying mechanisms of action. Ethanol, indometacin, and restraint water immersion stress-induced ulcerated models were used. The ulcer area was measured, and samples of gastric tissue were taken for pathological, histochemical, and biochemical analyses. OXY effectively reduced the area of gastric ulcers and improved the pathological changes of ulcerated tissue. OXY enhanced expression of Bcl-2, reduced Bax protein expression, and inhibited alcohol-induced apoptotic death in both ulcerated tissue and human gastric epithelial cells. OXY increased the prostaglandin E2 level and improved oxidative stress (malondialdehyde, superoxide dismutase, catalase, and nitric oxide) and inflammatory parameters (TNF-a, IL-6, and IL-1) of ulcer tissue. OXY prevented an inflammatory response via decreasing expression of p38, p-ERK, p-JNK, and inhibiting NF-κB p65 translocation from the cytoplasm to the nucleus. Our results reveal that OXY has remarkable protective effects on gastric ulcers. The action of OXY may be mediated via suppression of gastric inflammatory reactions, oxidative stress, and pro-apoptotic actions, which were the results of blockades of MAPKs and NF-κB signaling pathways. Our results provide evidence for the beneficial effects of OXY for treating peptic ulcers.


Assuntos
Alcaloides/farmacologia , Anti-Inflamatórios/farmacologia , Antiulcerosos/farmacologia , Antioxidantes/farmacologia , Quinolizinas/farmacologia , Úlcera Gástrica/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Linhagem Celular , Dinoprostona/metabolismo , Etanol , Mucosa Gástrica/efeitos dos fármacos , Humanos , Indometacina , Inflamação/tratamento farmacológico , Interleucinas/metabolismo , Masculino , Malondialdeído/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
17.
Nano Lett ; 17(9): 5291-5296, 2017 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-28786680

RESUMO

Grain boundaries (GBs) in polycrystalline graphene scatter charge carriers, which reduces carrier mobility and limits graphene applications in high-speed electronics. Here we report the extraction of the resistivity of GBs and the effect of GBs on carrier mobility by direct four-probe measurements on millimeter-sized graphene bicrystals grown by chemical vapor deposition (CVD). To extract the GB resistivity and carrier mobility from direct four-probe intragrain and intergrain measurements, an electronically equivalent extended 2D GB region is defined based on Ohm's law. Measurements on seven representative GBs find that the maximum resistivities are in the range of several kΩ·µm to more than 100 kΩ·µm. Furthermore, the mobility in these defective regions is reduced to 0.4-5.9‰ of the mobility of single-crystal, pristine graphene. Similarly, the effect of wrinkles on carrier transport can also be derived. The present approach provides a reliable way to directly probe charge-carrier scattering at GBs and can be further applied to evaluate the GB effect of other two-dimensional polycrystalline materials, such as transition-metal dichalcogenides (TMDCs).

18.
Pharm Biol ; 55(1): 799-809, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28112016

RESUMO

CONTEXT: Sonchus oleraceus L. (Asteraceae) (SO) is a dietary and traditional medicinal plant in China. However, its underlying mechanism of action as an anti-inflammatory agent is not known. OBJECTIVE: This study evaluates the anti-inflammatory activity of aqueous extract of SO. MATERIALS AND METHODS: The extract of SO was used to treat RAW 264.7 cells (in the working concentrations of 500, 250, 125, 62.5, 31.3 and 15.6 µg/mL) for 24 h. Pro-inflammatory cytokines and mediators produced in LPS-stimulated RAW 264.7 cells were assessed. Meanwhile, the expression level of TLR-4, COX-2, pSTATs and NF-κB was tested. Moreover, the anti-inflammatory activity of the extract in vivo was assessed using xylene-induced mouse ear oedema model and the anti-inflammatory compounds in the extracts were analyzed by HPLC-MS. RESULTS: SO extract significantly inhibited the production of pro-inflammatory cytokines and mediators at gene and protein levels with the concentration of 31.3 µg/mL, and suppressed the expression of TLR-4, COX-2, NF-κB and pSTAT in RAW 264.7 cells. The anti-inflammatory activity of SO in vivo has significant anti-inflammatory effects with the concentration of 250 and 125 mg/kg, and less side effect on the weights of the mice at the concentration of 250 mg/kg. Moreover, HPLC-MS analysis revealed that the anti-inflammatory compounds in the extract were identified as villosol, ferulaic acid, ß-sitosterol, ursolic acid and rutin. DISCUSSION AND CONCLUSION: This study indicated that SO extract has anti-inflammatory effects in vitro and in vivo, which will be further developed as novel pharmacological strategies in order to defeat inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Lipopolissacarídeos/farmacologia , Extratos Vegetais/farmacologia , Sonchus , Animais , Sobrevivência Celular/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase 2/farmacologia , Citocinas/antagonistas & inibidores , Citocinas/genética , Masculino , Camundongos , NF-kappa B/análise , Extratos Vegetais/análise , Células RAW 264.7 , Sonchus/química , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/genética
19.
J Exp Bot ; 67(6): 1935-50, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26873979

RESUMO

Accumulating evidence indicates that plant MYB transcription factors participate in defense against pathogen attack, but their regulatory targets and related signaling processes remain largely unknown. Here, we identified a defense-related MYB gene (GhMYB108) from upland cotton (Gossypium hirsutum) and characterized its functional mechanism. Expression of GhMYB108 in cotton plants was induced by Verticillium dahliae infection and responded to the application of defense signaling molecules, including salicylic acid, jasmonic acid, and ethylene. Knockdown of GhMYB108 expression led to increased susceptibility of cotton plants to V. dahliae, while ecotopic overexpression of GhMYB108 in Arabidopsis thaliana conferred enhanced tolerance to the pathogen. Further analysis demonstrated that GhMYB108 interacted with the calmodulin-like protein GhCML11, and the two proteins form a positive feedback loop to enhance the transcription of GhCML11 in a calcium-dependent manner. Verticillium dahliae infection stimulated Ca(2+) influx into the cytosol in cotton root cells, but this response was disrupted in both GhCML11-silenced plants and GhMYB108-silenced plants in which expression of several calcium signaling-related genes was down-regulated. Taken together, these results indicate that GhMYB108 acts as a positive regulator in defense against V. dahliae infection by interacting with GhCML11. Furthermore, the data also revealed the important roles and synergetic regulation of MYB transcription factor, Ca(2+), and calmodulin in plant immune responses.


Assuntos
Retroalimentação Fisiológica , Gossypium/imunologia , Gossypium/microbiologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Verticillium/fisiologia , Arabidopsis/genética , Cálcio/metabolismo , Sinalização do Cálcio/genética , Núcleo Celular/metabolismo , Citosol/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Gossypium/genética , Doenças das Plantas/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Ligação Proteica , Domínios Proteicos , Frações Subcelulares/metabolismo , Transativadores/metabolismo , Transcrição Gênica
20.
Tumour Biol ; 37(10): 14165-14171, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27542674

RESUMO

Acquired evidence indicated that microRNAs (miRNAs) played essential roles in cancer development, including hepatocellular carcinoma (HCC). Functions and mechanisms of miRNAs involved in HCC remain largely unknown. Here, we found that miR-384 was significantly downregulated in HCC cells and tissues by RT-PCR. Gain and loss of function studies revealed that miR-384 significantly suppressed HCC cell proliferation. Insulin receptor substrate 1(IRS1) was identified as a direct and functional target of miR-384. Moreover, miR-384 decreased IRS1 expression, subsequently downregulating cyclin D1 and upregulating p21 and p-Rb expression. In addition, promotion of cell proliferation caused by miR-384-in was counteracted by silencing IRS1 expression with siRNAs. Taken together, our data provided convincing evidence that miR-384 exerted suppressive effect on HCC cell proliferation through the direct inhibition of IRS1 expression, suggesting miR-384 may serve as a potential therapeutic target for HCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/patologia , Proteínas Substratos do Receptor de Insulina/metabolismo , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Apoptose , Biomarcadores Tumorais/genética , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proliferação de Células , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
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