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1.
Toxicol Appl Pharmacol ; 487: 116969, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38744347

RESUMO

Cysteine and glycine-rich protein 2 (CSRP2) is expressed differently in numerous cancers and plays a key role in carcinogenesis. However, the role of CSRP2 in glioma is unknown. This study sought to determine the expression profile and clinical significance of CSRP2 in glioma and explore its biological functions and mechanisms via lentivirus-mediated CSRP2 silencing experiments. Increased CSRP2 was frequently observed in gliomas, which was associated with clinicopathological characteristics and an unfavourable prognosis. Decreasing CSRP2 led to the suppression of malignant proliferation, metastasis and stemness in glioma cells while causing hypersensitivity to chemotherapeutic drugs. Mechanistic investigations revealed that CSRP2 plays a role in mediating the Notch signalling cascade. Silencing CSRP2 decreased the levels of Notch1, cleaved Notch1, HES1 and HEY1, suppressing the Notch signalling cascade. Reactivation of Notch markedly diminished the tumour-inhibiting effects of CSRP2 silencing on the malignant phenotypes of glioma cells. Notably, CSRP2-silencing glioma cells exhibited reduced potential in the formation of xenografts in nude mice in vivo, which was associated with an impaired Notch signalling cascade. These results showed that CSRP2 is overexpressed in glioma and has a crucial role in sustaining the malignant phenotypes of glioma, suggesting that targeting CSRP2 could be a promising strategy for glioma treatment.


Assuntos
Glioma , Camundongos Nus , Transdução de Sinais , Humanos , Glioma/patologia , Glioma/metabolismo , Glioma/genética , Animais , Linhagem Celular Tumoral , Camundongos , Masculino , Proliferação de Células , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Feminino , Fenótipo , Receptores Notch/metabolismo , Receptores Notch/genética , Receptor Notch1/metabolismo , Receptor Notch1/genética , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Regulação Neoplásica da Expressão Gênica , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Altern Ther Health Med ; 30(1): 102-110, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37773652

RESUMO

Objective: A large proportion of patients undergoing assisted reproductive therapy (ART) suffer from premature ovarian insufficiency (POI). The knowledge structure, research hotspots, and research trends related to ART for patients with POI are still unclear and have not been systematically summarized. We aimed to analyze the research status of ART for patients with POI and deeply explore its knowledge structure and research trends. Our findings may provide treatment recommendations for clinicians and guidance for researchers in further research. Methods: The PubMed database for publications on ART for patients with POI was searched. The Bibliographic Item Co-occurrence Matrix Builder (BICOMB) obtained the Co-word matrix and co-occurrence matrix. The H-index method was used to extract high-frequency main Medical Subject Headings (MeSH) terms/subheadings. Then we used software such as graphical clustering toolkit (gCluto), Microsoft Excel, Ucinet and NetDraw to carry out the biclustering analysis, strategic diagram analysis and social network analysis of the major MeSH terms/subheadings. Results: The high-frequency major MeSH terms/subheadings were analyzed by biclustering, strategic diagram, and social network analyses. A total of 431 articles from 1983 to 2023 were retrieved. Analysis showed that a total of 176 journals published relevant papers, including FERTILITY AND STERILITY, ranking first. In addition, we extracted 20 high-frequency major MeSH terms/subheadings. We grouped them into five categories: cryopreservation of oocyte and ovarian tissue, oocyte donation, in vitro activation (IVA) of primordial follicles, overview of therapy for patients with POI, therapy of iatrogenic POI. Within these five categories, there were 4, 4, 3, 4, and 5 major MeSH terms/subheadings, respectively. The major MeSH terms/subheadings were evenly distributed, and no particular group had a particular central tendency. Conclusion: The therapy of Iatrogenic POI is in the core position of research and is becoming increasingly mature. Oocyte donation and IVA of primordial follicles are the trends of future research. This study is helpful to understand the current research status, knowledge structure, and research trends of ART for patients with POI, and provide reference for improving ART for patients with POI in the future. Our study may guide clinicians to apply more established research to treat patients, which may lead to better treatment outcomes for patients. At the same time, we also suggest that researchers can conduct research in the field of future research trends, which may lead to greater research results.


Assuntos
Infertilidade , Técnicas de Reprodução Assistida , Humanos , Bibliometria , Fertilidade , Doença Iatrogênica
3.
Eur Heart J ; 40(48): 3924-3933, 2019 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-31365073

RESUMO

AIMS: A persistent cardiac T-cell response initiated by myocardial infarction is linked to subsequent adverse ventricular remodelling and progression of heart failure. No data exist on T-cell receptor (TCR) repertoire changes in combination with phenotypic characterization of T cells in ischaemic failing human hearts. METHODS AND RESULTS: Analysis of TCR repertoire with high-throughput sequencing revealed that compared with T cells in control hearts, those in ischaemic failing hearts showed a clonally expanded TCR repertoire but similar usage patterns of TRBV-J rearrangements and V gene segments; compared with T cells in peripheral blood, those in ischaemic failing hearts exhibited a restricted and clonally expanded TCR repertoire and different usage patterns of TRBV-J rearrangements and V gene segments, suggesting the occurrence of tissue-specific T-cell expansion in ischaemic failing hearts. Consistently, TCR clonotype sharing was prominent in ischaemic failing hearts, especially in hearts of patients who shared human leucocyte antigen (HLA) alleles. Furthermore, ischaemia heart failure (IHF) heart-associated clonotypes were more frequent in peripheral blood of IHF patients than in that of controls. Heart-infiltrating T cells displayed memory- and effector-like characteristics. Th1 cells were the predominant phenotype among CD4+ T cells; CD8+ T cells were equally as abundant as CD4+ T cells and produced high levels of interferon-γ, granzyme B, and perforin. CONCLUSION: We provide novel evidence for a tissue-specific T-cell response predominated by Th1 cells and cytotoxic CD8+ T cells in ischaemic failing human hearts that may contribute to the progression of heart failure.


Assuntos
Insuficiência Cardíaca/patologia , Infarto do Miocárdio/patologia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/patologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Estudos de Casos e Controles , Células Clonais/metabolismo , Progressão da Doença , Granzimas/metabolismo , Insuficiência Cardíaca/metabolismo , Humanos , Memória Imunológica/genética , Interferon gama/metabolismo , Isquemia , Infarto do Miocárdio/metabolismo , Perforina/metabolismo , Fenótipo , Remodelação Ventricular
4.
Mikrochim Acta ; 187(10): 578, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32975594

RESUMO

Molecularly imprinted stir-bar coatings were created based on a hydroxylcucurbit[7]uril-paraquat inclusion complex. The inclusion complex that contained paraquat (PQ) as a template and monohydroxylcucurbit[7]uril ((OH)Q[7]) as a monomer was preassembled mainly through cavity inclusion interaction of (OH)Q[7] to form a one-dimensional self-assembly structure. The inclusion complex was anchored chemically on the surface of a glass stir bar with hydroxy-terminated poly(dimethylsiloxane) by the sol-gel technique to obtain a molecularly imprinted polymer-coated stir bar (MIP-SB). The molecularly imprinted coating showed specific adsorption for cationic PQ in aqueous media. Other quaternary amine compounds with a similar structure that coexisted in the solution, such as ethyl-viologen, diquat, and difenzoquat, were almost not extracted by the prepared MIP-SB. The sorptive capacity of the MIP-SB for PQ was nearly four times that of the non-imprinted stir bar (NIP-SB). The recognition mechanism indicated that the selectivity and extraction capacity resulted mainly from the imprinted cavity in the polymer that was formed by a one-dimensional assembly structure consisting of the (OH)Q[7]-PQ inclusion complex. The imprinted cavity was complementary to the PQ in shape, size, and functionality. A method to determine PQ in environmental water and vegetable samples was developed by combining MIP-SB sorptive extraction with HPLC-UV. The linear range was from 100 to 10,000 ng L-1 with a 8.2 ng L-1 detection limit for water samples and 0.02-0.85 mg kg-1 with a 0.005 mg kg-1 detection limit for vegetable samples. The limit of detection for both samples was lower than the EU-established maximum residual levels and that of other previously reported methods. The average recoveries were 70.0-96.1% with a relative standard deviation ≤ 7.6%, which showed the successful application in real sample analysis. Molecularly imprinted stir-bar coatings were created based on a hydroxylcucurbit[7]uril-paraquat (PQ) inclusion complex, which showed a specific recognition toward cationic PQ. A method to determine PQ in environmental water and vegetable samples was established by combining MIP-SB sorptive extraction with HPLC-UV.


Assuntos
Impressão Molecular/métodos , Paraquat/efeitos adversos , Verduras/química , Água/química , Humanos
5.
Mikrochim Acta ; 186(12): 846, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776838

RESUMO

A detailed study has been carried out on monohydroxycucurbit[7]uril-based stir-bar sorptive extraction (SBSE). A polydimethylsiloxane coating was produced by a sol-gel technique and doped with monohydroxycucurbit[7]uril ((HO)1Q [7]) as a selective sorbent phase. (HO)1Q [7] was chemically bound to the sol-gel silica substrate through hydrolysis and polycondensation. The coating possesses a porous surface, shows strong solvent resistance and good thermal stability, and has a long lifespan. Four groups of compounds, with polarities ranging from apolar polycyclic aromatic hydrocarbons to polar ketones, aromatic amines and phenols, were selected as test analytes. They were extracted with the coated stir bar, then desorbed with methanol and quantified by high-performance liquid chromatography with ultraviolet detection. The limits of detection range between 1.3 and 15 µg L-1, the linear ranges extend from 5 to 10,000 µg L-1, and the relative recoveries from spiked samples range between 76.4 and 97.9%. The intraday relative standard deviations range from 2.3 to 8.6% (for n = 3, at 500 µg L-1). Compared with a commercial PDMS-coated stir bar and a polyether sulfone-coated stir bar, the new stir bar shows wider applicability and better extraction efficiency for each group of compounds. In addition, the stir bar can simultaneously extract mixtures of chemicals of different polarities. This endows it with the potential for recovering a broad group of polar organic compounds. Graphical abstractA stir bar for sorptive extraction based on monohydroxycucurbit[7]uril has been prepared by a sol-gel technique. The stir bar coupled with HPLC with UV detection allows for the determination of a variety of polar compounds and multicomponent mixtures, respectively.

6.
PLoS Comput Biol ; 10(2): e1003420, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24586125

RESUMO

The standard approach for identifying gene networks is based on experimental perturbations of gene regulatory systems such as gene knock-out experiments, followed by a genome-wide profiling of differential gene expressions. However, this approach is significantly limited in that it is not possible to perturb more than one or two genes simultaneously to discover complex gene interactions or to distinguish between direct and indirect downstream regulations of the differentially-expressed genes. As an alternative, genetical genomics study has been proposed to treat naturally-occurring genetic variants as potential perturbants of gene regulatory system and to recover gene networks via analysis of population gene-expression and genotype data. Despite many advantages of genetical genomics data analysis, the computational challenge that the effects of multifactorial genetic perturbations should be decoded simultaneously from data has prevented a widespread application of genetical genomics analysis. In this article, we propose a statistical framework for learning gene networks that overcomes the limitations of experimental perturbation methods and addresses the challenges of genetical genomics analysis. We introduce a new statistical model, called a sparse conditional Gaussian graphical model, and describe an efficient learning algorithm that simultaneously decodes the perturbations of gene regulatory system by a large number of SNPs to identify a gene network along with expression quantitative trait loci (eQTLs) that perturb this network. While our statistical model captures direct genetic perturbations of gene network, by performing inference on the probabilistic graphical model, we obtain detailed characterizations of how the direct SNP perturbation effects propagate through the gene network to perturb other genes indirectly. We demonstrate our statistical method using HapMap-simulated and yeast eQTL datasets. In particular, the yeast gene network identified computationally by our method under SNP perturbations is well supported by the results from experimental perturbation studies related to DNA replication stress response.


Assuntos
Inteligência Artificial , Bases de Dados de Ácidos Nucleicos , Redes Reguladoras de Genes , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Algoritmos , Biologia Computacional , Simulação por Computador , DNA Fúngico/genética , Perfilação da Expressão Gênica , Humanos , Modelos Lineares , Modelos Genéticos , Modelos Estatísticos , Saccharomyces cerevisiae/genética
7.
Nat Nanotechnol ; 19(2): 173-180, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38036659

RESUMO

Precise control of the conductivity of layered ferroelectric semiconductors is required to make these materials suitable for advanced transistor, memory and logic circuits. Although proof-of-principle devices based on layered ferroelectrics have been demonstrated, it remains unclear how the polarization inversion induces conductivity changes. Therefore, function design and performance optimization remain cumbersome. Here we combine ab initio calculations with transport experiments to unveil the mechanism underlying the polarization-dependent conductivity in ferroelectric channel field-effect transistors. We find that the built-in electric field gives rise to an asymmetric conducting route formed by the hidden Stark effect and competes with the potential redistribution caused by the external field of the gate. Furthermore, leveraging our mechanistic findings, we control the conductivity threshold in α-In2Se3 ferroelectric channel field-effect transistors. We demonstrate logic-in-memory functionality through the implementation of electrically self-switchable primary (AND, OR) and composite (XOR, NOR, NAND) logic gates. Our work provides mechanistic insights into conductivity modulation in a broad class of layered ferroelectrics, providing foundations for their application in logic and memory electronics.

8.
Sci Rep ; 14(1): 1713, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38242911

RESUMO

Ketone bodies serve as an energy source, especially in the absence of carbohydrates or in the extended exercise. Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is a crucial energy sensor that regulates lipid and glucose metabolism. However, whether AMPK regulates ketone metabolism in whole body is unclear even though AMPK regulates ketogenesis in liver. Prolonged resulted in a significant increase in blood and urine levels of ketone bodies in wild-type (WT) mice. Interestingly, fasting AMPKα2-/- and AMPKα1-/- mice exhibited significantly higher levels of ketone bodies in both blood and urine compared to fasting WT mice. BHB tolerance assays revealed that both AMPKα2-/- and AMPKα1-/- mice exhibited slower ketone consumption compared to WT mice, as indicated by higher blood BHB or urine BHB levels in the AMPKα2-/- and AMPKα1-/- mice even after the peak. Interestingly, fasting AMPKα2-/- and AMPKα1-/- mice exhibited significantly higher levels of ketone bodies in both blood and urine compared to fasting WT mice. . Specifically, AMPKα2ΔMusc mice showed approximately a twofold increase in blood BHB levels, and AMPKα2ΔMyo mice exhibited a 1.5-fold increase compared to their WT littermates after a 48-h fasting. However, blood BHB levels in AMPKα1ΔMusc and AMPKα1ΔMyo mice were as same as in WT mice. Notably, AMPKα2ΔMusc mice demonstrated a slower rate of BHB consumption in the BHB tolerance assay, whereas AMPKα1ΔMusc mice did not show such an effect. Declining rates of body weights and blood glucoses were similar among all the mice. Protein levels of SCOT, the rate-limiting enzyme of ketolysis, decreased in skeletal muscle of AMPKα2-/- mice. Moreover, SCOT protein ubiquitination increased in C2C12 cells either transfected with kinase-dead AMPKα2 or subjected to AMPKα2 inhibition. AMPKα2 physiologically binds and stabilizes SCOT, which is dependent on AMPKα2 activity.


Assuntos
Proteínas Quinases Ativadas por AMP , Corpos Cetônicos , Animais , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Jejum , Cetonas , Camundongos Knockout , Ubiquitinação , Coenzima A-Transferases/metabolismo
9.
Neuro Oncol ; 25(6): 1073-1084, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-36591963

RESUMO

BACKGROUND: Systemic delivery of anti-tumor therapeutic agents to brain tumors is thwarted by the blood-brain barrier (BBB), an organotypic specialization of brain endothelial cells (ECs). A failure of pharmacological compounds to cross BBB is one culprit for the dismal prognosis of glioblastoma (GBM) patients. Identification of novel vascular targets to overcome the challenges posed by the BBB in tumors for GBM treatment is urgently needed. METHODS: Temozolomide (TMZ) delivery was investigated in CT2A and PDGFB-driven RCAS/tv-a orthotopic glioma models. Transcriptome analysis was performed on ECs from murine gliomas. Mfsd2a deficient, Cav1 deficient, and Mfsd2a EC-specific inducible mice were developed to study the underlying molecular mechanisms. RESULTS: We demonstrated that inhibiting Wnt signaling by LGK974 could increase TMZ delivery and sensitize glioma to chemotherapy in both murine glioma models. Transcriptome analysis of ECs from murine gliomas revealed that Wnt signaling inhibition enhanced vascular transcytosis as indicated by the upregulation of PLVAP and downregulation of MFSD2A. Mfsd2a deficiency in mice enhances TMZ delivery in tumors, whereas constitutive expression of Mfsd2a in ECs suppresses the enhanced TMZ delivery induced by Wnt pathway inhibition in murine glioma. In addition, Wnt signaling inhibition enhanced caveolin-1 (Cav1)-positive caveolae-mediated transcytosis in tumor ECs. Moreover, Wnt signaling inhibitor or Mfsd2a deficiency fails to enhance TMZ penetration in tumors from Cav1-deficient mice. CONCLUSIONS: These results demonstrated that Wnt signaling regulates MFSD2A-dependent TMZ delivery through a caveolae-mediated EC transcytosis pathway. Our findings identify Wnt signaling as a promising therapeutic target to improve drug delivery for GBM treatment.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Simportadores , Camundongos , Animais , Via de Sinalização Wnt , Células Endoteliais/metabolismo , Glioma/tratamento farmacológico , Glioma/metabolismo , Temozolomida/uso terapêutico , Glioblastoma/patologia , Neoplasias Encefálicas/patologia , Transcitose , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Simportadores/metabolismo , Simportadores/uso terapêutico
10.
Food Chem ; 350: 129236, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33610850

RESUMO

Cucurbit[7]uril (Q[7]) was first used as a dispersant sorbent material in a matrix solid-phase dispersion for the simultaneous extraction of four quaternary ammonium pesticides from vegetables before analysis using high-performance liquid chromatography with UV detection. Q[7] exhibited a better selectivity and adsorption capability for these compounds, which is due to its ability to bind selectively organic molecules into its hydrophobic cavity and to form stable host-guest inclusion complexes. Various parameters affecting the extraction were investigated and optimized, such as sorbent/sample mass ratio, grinding time, rinsing and eluting conditions. Under optimized conditions, the proposed method exhibited a linear response in the concentration range of 1-100 µg·kg-1, satisfactory recoveries for eight types of vegetable samples (>70%), and high repeatability (RSD < 9.0%). The limits of quantification were between 0.43 µg·kg-1 and 0.99 µg·kg-1, which is nearly 50 times lower than the maximum residue limits established by the European Council.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/análise , Cromatografia Líquida de Alta Pressão/métodos , Imidazóis/análise , Praguicidas/isolamento & purificação , Compostos de Amônio Quaternário/isolamento & purificação , Espectrofotometria Ultravioleta/métodos , Verduras/química , Adsorção , Limite de Detecção , Extração em Fase Sólida/métodos
11.
Front Oncol ; 11: 683367, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222002

RESUMO

PURPOSE: Glioblastoma (GBM) is the most aggressive and lethal type of brain tumors. Magnetic resonance imaging (MRI) has been commonly used for GBM diagnosis. Contrast enhancement (CE) on T1-weighted sequences are presented in nearly all GBM as a result of high vascular permeability in glioblastomas. Although several radiomics studies indicated that CE is associated with distinct molecular signatures in tumors, the effects of vascular endothelial cells, the key component of blood brain barrier (BBB) controlling vascular permeability, on CE have not been thoroughly analyzed. METHODS: Endothelial cell enriched genes have been identified using transcriptome data from 128 patients by a systematic method based on correlation analysis. Distinct endothelial cell enriched genes associated with CE were identified by analyzing difference of correlation score between CE-high and CE-low GBM cases. Immunohistochemical staining was performed on in-house patient cohort to validate the selected genes associated with CE. Moreover, a survival analysis was conducted to uncover the relation between CE and patient survival. RESULTS: We illustrated that CE is associated with distinct vascular molecular imprints characterized by up-regulation of pro-inflammatory genes and deregulation of BBB related genes. Among them, PLVAP is up-regulated, whereas TJP1 and ABCG2 are down-regulated in the vasculature of GBM with high CE. In addition, we found that the high CE is associated with poor prognosis and GBM mesenchymal subtype. CONCLUSION: We provide an additional insight to reveal the molecular trait for CE in MRI images with special focus on vascular endothelial cells, linking CE with BBB disruption in the molecular level. This study provides a potential new direction that may be applied for the treatment optimization based on MRI features.

12.
Front Chem ; 8: 31, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117868

RESUMO

A novel monohydroxycucurbit[7]uril-based stationary phase for capillary gas chromatography (GC) has been produced. For this, a capillary column coating was made using a sol-gel technique, incorporating synthesized monohydroxycucurbit[7]uril [(OH)Q[7]] and hydroxy-terminated poly(dimethylsiloxane) (OH-PDMS) into the sol-gel network through hydrolysis and polycondensation and chemical sol-gel grafting to the inner wall of a fused-silica tube. The preparation method may produce a coating with greater integrity, which gives the prepared column a higher separation efficiency and better selectivity toward analytes than a reported stationary phase based on neat cucurbit[n]urils (Q[n]s). The prepared (OH)Q[7]/PDMS column had 3,225 theoretical plates per meter determined using naphthalene at 120°C and exhibited a weakly polar nature. The (OH)Q[7]/PDMS column has high resolution over a broad spectrum of analytes with symmetrical peak shapes and exhibited better separation performance than commercial capillary columns and reported columns based on neat Q[n]s that failed to resolve some critical analytes. Moreover, the column also showed good thermal stability up to 300°C and separation repeatability with relative standard deviation values in the range of 0.01-0.11% for intraday, 0.11-0.32% for interday and 0.29-0.58% for column-to-column. In addition, the energy effect on the retention of analytes on the (OH)Q[7]/PDMS stationary phase was investigated. The results indicated that retention on the column was determined mainly by the enthalpy change. As demonstrated, the proposed coating method can address some disadvantages that exist with the reported Q[n]s columns and combine the full advantages of (OH)Q[7] with the sol-gel coating method while achieving outstanding GC separation performance.

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