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1.
Acta Psychol (Amst) ; 247: 104313, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38810356

RESUMO

This study investigates the impact of segmental accuracy and nucleus placement on the comprehensibility of English as an International Language (EIL), with the aim of informing phonological norms and teaching models. Speech samples from 59 EIL speakers with varying levels of segmental accuracy were collected during a reading task, involving reading a passage in three different versions of speech, each version lasting approximately 30 to 40 s. To directly compare the impact of nuclear stress placement on comprehensibility, based on these samples, two versions of stimuli were created, each differing only in their placement of nuclear stress - either correct or incorrect. The correctness of placements was determined by seven native speakers of English. Eight native English speakers, aged 19-24, and eight EIL speakers, aged 20-24 with an upper-intermediate to advanced proficiency level, rated the comprehensibility of the two versions of speech. Results suggest that while correct nucleus placement enhances comprehensibility for native English listeners, it has little influence on EIL listeners. Segmental accuracy in EIL speech impacts comprehensibility substantially more than nucleus placement on both native and EIL listeners, indicating that English language teaching should focus on minimizing segmental errors to improve comprehensibility for EIL speakers, despite the benefits of correct nucleus placement.


Assuntos
Compreensão , Leitura , Humanos , Masculino , Feminino , Adulto Jovem , Compreensão/fisiologia , Percepção da Fala/fisiologia , Fonética , Idioma , Adulto , Multilinguismo , Fala/fisiologia
2.
Exp Mol Med ; 56(2): 441-452, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38383581

RESUMO

Helicobacter pylori, particularly cytotoxin-associated gene A (CagA)-positive strains, plays a key role in the progression of gastric cancer (GC). Ferroptosis, associated with lethal lipid peroxidation, has emerged to play an important role in malignant and infectious diseases, but the role of CagA in ferroptosis in cancer cells has not been determined. Here, we report that CagA confers GC cells sensitivity to ferroptosis both in vitro and in vivo. Mechanistically, CagA promotes the synthesis of polyunsaturated ether phospholipids (PUFA-ePLs), which is mediated by increased expression of alkylglycerone phosphate synthase (AGPS) and 1-acylglycerol-3-phosphate O-acyltransferase 3 (AGPAT3), leading to susceptibility to ferroptosis. This susceptibility is mediated by activation of the MEK/ERK/SRF pathway. SRF is a crucial transcription factor that increases AGPS transcription by binding to the AGPS promoter region. Moreover, the results demonstrated that CagA-positive cells are more sensitive to apatinib than are CagA-negative cells, suggesting that detecting the H. pylori CagA status may aid patient stratification for treatment with apatinib.


Assuntos
Ferroptose , Helicobacter pylori , Neoplasias Gástricas , Humanos , Citotoxinas , Éteres Fosfolipídicos
3.
Psychol Res ; 88(3): 762-772, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37880423

RESUMO

In this study, we examined the gestural embodiment of active, passive, and active-form/passive-sense voices of ergative verbs in English. We analyzed gestures produced by presenters talking about a variety of subjects in a set of videos. We used several Chi-square tests to find out what type of gesture (representational, beat, and pointing gestures) co-occurred more frequently with active, passive, and active-form/passive-sense voices of ergative verbs. The results showed that representational gestures occurred more frequently with active than passive and active-form/passive-sense voices of ergative verbs. Furthermore, representational gestures occurred more frequently with active voices of ergative verbs having human subjects than non-human subjects. This was also the case with active-form/passive-sense sentences. Based on these results, it is suggested that form of a sentence is an influential factor in the process of embodying the situation that is described by that sentence. Active voice of an English ergative verb is more likely to be accompanied by representational gestures and is embodied more strongly than passive and active-form/passive-sense voices of that verb.


Assuntos
Gestos , Idioma , Humanos , Sujeitos da Pesquisa
4.
Adv Sci (Weinh) ; 10(23): e2300898, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37328448

RESUMO

Anti-angiogenic therapy has long been considered a promising strategy for solid cancers. Intrinsic resistance to hypoxia is a major cause for the failure of anti-angiogenic therapy, but the underlying mechanism remains unclear. Here, it is revealed that N4-acetylcytidine (ac4C), a newly identified mRNA modification, enhances hypoxia tolerance in gastric cancer (GC) cells by promoting glycolysis addiction. Specifically, acetyltransferase NAT10 transcription is regulated by HIF-1α, a key transcription factor of the cellular response to hypoxia. Further, acRIP-sequencing, Ribosome profiling sequencing, RNA-sequencing, and functional studies confirm that NAT10 in turn activates the HIF-1 pathway and subsequent glucose metabolism reprogramming by mediating SEPT9 mRNA ac4C modification. The formation of the NAT10/SEPT9/HIF-1α positive feedback loop leads to excessive activation of the HIF-1 pathway and induces glycolysis addiction. Combined anti-angiogenesis and ac4C inhibition attenuate hypoxia tolerance and inhibit tumor progression in vivo. This study highlights the critical roles of ac4C in the regulation of glycolysis addiction and proposes a promising strategy to overcome resistance to anti-angiogenic therapy by combining apatinib with ac4C inhibition.


Assuntos
Neoplasias Gástricas , Humanos , Retroalimentação , Glicólise , RNA Mensageiro , Hipóxia , Acetiltransferases N-Terminal
5.
Mol Ther Oncolytics ; 24: 547-560, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35229032

RESUMO

Association of tumor microenvironment and immune checkpoint (e.g., PD-L1) is important for immune escape, impacting chemotherapy and immunotherapy efficacy. We aimed to investigate biomarkers and therapeutic targets against treatment resistance in gastric cancer. Abundances of tumor-infiltrating immune cells were estimated in multiple datasets. Three patient subgroups (A, B, and C) were identified based on seven types of PD-L1- and IFN-γ-associated immune cells. Patients yielded increased prognosis from subgroup A to C (p = 0.027). Subgroup A was characterized by high activated CD4+ memory T cell infiltration, while more resting CD4+ memory T cells were in subgroup C. Further, a risk score was developed for prognostication. Lipoma preferred partner (LPP), as the hub gene in subgroup-related regulatory network, was upregulated (p < 0.01) and was associated with high risk score (p < 0.001) and poor survival (p < 0.05). Bioinformatics analyses and experiments found that LPP expressed restrictively in fibroblasts and associated with activated CD4+ memory T cell infiltration and tumor growth. High-LPP patients yielded fewer benefits from chemotherapy or immunotherapy, compared with the low-LPP group. We finally identified 28 compounds as sensitive drugs for high-LPP patients. Our findings suggested LPP might be a biomarker for treatment response and therapeutic target in gastric cancer.

6.
Phytochem Anal ; 33(2): 239-248, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34390060

RESUMO

INTRODUCTION: The roots of Stephania succifera are used in traditional medicine for the treatment of several diseases. Research on this plant has mainly focused on bioactive alkaloids from the roots, and no previous work on compounds from the abundant leaves has yet been reported. OBJECTIVE: To identify and compare alkaloidal compounds in S. succifera roots and leaves and to predict the potential bioactivity of some alkaloids. METHODS: High-performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry (HPLC-QTOF-MS/MS) was employed to identify alkaloidal compounds from S. succifera. The potential targets and bioactivities of most alkaloids were predicted using the PharmMapper server. RESULTS: Fifty-six alkaloidal compounds, including protoberberine-, aporphine-, proaporphine-, benzylisoquinoline-, and lactam-type alkaloids, were identified or tentatively identified in S. succifera roots and leaves based on the HPLC-MS data. Forty-one compounds have not been previously reported in S. succifera and eight of them have not been previously reported in the literature. Twenty-four alkaloidal compounds were found in both roots and leaves. Twelve potential targets with different indications were predicted for some alkaloids. CONCLUSION: Comparison of chemical constituents and their potential bioactivities for S. succifera roots and leaves indicated that diverse bioactive alkaloids were present in the leaves as well as the roots. PharmMapper provided new directions for bioactivity screening. This study will be helpful for further understanding the medicinal components of S. succifera and the rational utilisation of plant resources.


Assuntos
Alcaloides , Stephania , Alcaloides/análise , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/química , Folhas de Planta/química , Stephania/química , Espectrometria de Massas em Tandem/métodos
7.
Theranostics ; 10(17): 7545-7560, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32685004

RESUMO

Rationale: Peritoneal metastasis predicts poor prognosis of gastric cancer (GC) patients, and the underlying mechanisms are poorly understood. Methods: The 2-DIGE, MALDI-TOF/TOF MS and single-cell transcriptome were used to detect differentially expressed proteins among normal gastric mucosa, primary GC and peritoneal metastatic tissues. Lentiviruses carrying shRNA and transcription activator-like effector nuclease technology were used to knock down myosin heavy chain 9 (MYH9) expression in GC cell lines. Immunofluorescence, immune transmission electron microscopy, chromatin fractionation, co-immunoprecipitation, and assays for chromatin immunoprecipitation, dual luciferase reporter, agarose-oligonucleotide pull-down, flow cytometry and cell anoikis were performed to uncover nuclear MYH9-induced ß-catenin (CTNNB1) transcription in vitro. Nude mice and conditional transgenic mice were used to investigate the findings in vivo. Results: We observed that MYH9 was upregulated in metastatic GC tissues and was associated with a poor prognosis of GC patients. Mechanistically, we confirmed that MYH9 was mainly localized in the GC cell nuclei by four potential nuclear localization signals. Nuclear MYH9 bound to the CTNNB1 promoter through its DNA-binding domain, and interacted with myosin light chain 9, ß-actin and RNA polymerase II to promote CTNNB1 transcription, which conferred resistance to anoikis in GC cells in vitro and in vivo. Staurosporine reduced nuclear MYH9 S1943 phosphorylation to inhibit CTNNB1 transcription, Wnt/ß-catenin signaling activation and GC progression in both orthotropic xenograft GC nude mouse and transgenic GC mouse models. Conclusion: This study identified that nuclear MYH9-induced CTNNB1 expression promotes GC metastasis, which could be inhibited by staurosporine, indicating a novel therapy for GC peritoneal metastasis.


Assuntos
Anoikis/genética , Neoplasias Pulmonares/genética , Cadeias Pesadas de Miosina/metabolismo , Estaurosporina/farmacologia , Neoplasias Gástricas/patologia , beta Catenina/genética , Animais , Anoikis/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Quimioterapia Adjuvante/métodos , Feminino , Gastrectomia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/secundário , Masculino , Camundongos , Camundongos Transgênicos , Cadeias Pesadas de Miosina/genética , Fosforilação/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Estaurosporina/uso terapêutico , Estômago/patologia , Estômago/cirurgia , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Ativação Transcricional/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Exp Clin Cancer Res ; 39(1): 1, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31928527

RESUMO

BACKGROUND: Circular RNAs (circRNAs) have recently emerged as a new family of noncoding RNAs that are involved in the causation and progression of various cancers. However, the roles of circRNAs in the tumorigenesis of gastric cancer (GC) are still largely unknown. METHODS: The expression profiles of circRNAs in GC were identified in open GEO database and were evaluated at the mRNA level in clinical GC samples compared with paired non-tumorous tissues. Kaplan-Meier survival curve was used to analyze the correlation of circRNA and patients' prognosis. Subsequently, the circular structures of candidate circRNAs were validated by Sanger sequencing, divergent primer PCR, and RNase R treatments. Gain- and loss-of-function analyses were performed to evaluate the functional significance of it in GC initiation and progression. Dual-luciferase reporter and RNA pull-down assays were used to identify the microRNA (miRNA) sponge mechanism of circRNAs. RESULTS: The expression of circRHOBTB3 was lower in GC tissues and cell lines. Downregulation of circRHOBTB3 was significantly correlated with poor differentiation and unfavorable prognosis in patients with GC. Overexpression of circRHOBTB3 in GC cells led to decreased proliferation and induced G1/S arrest in vitro, accompanied with inhibited xenograft tumor growth in vivo, while the opposite effects were achieved in circRHOBTB3-silenced cells. Furthermore, we demonstrated that circRHOBTB3 acts as a sponge for miR-654-3p and verified that p21 is a novel target of miR-654-3p. CONCLUSION: Taken together, this study revealed that circRHOBTB3 might function as competing endogenous RNA (ceRNA) for miR-654-3p, which could contribute to growth inhibition of GC through activating p21 signaling pathway. Our data suggested that circRHOBTB3 would serve as a novel promising diagnosis marker and therapeutic target for GC.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/genética , MicroRNAs/genética , RNA Circular/genética , Neoplasias Gástricas/patologia , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Transplante de Neoplasias , Prognóstico , Neoplasias Gástricas/genética , Análise de Sobrevida
9.
Gene ; 696: 47-53, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771479

RESUMO

OBJECTIVE: This study aimed to investigate the biological role of C5orf34 in Lung adenocarcinoma (LAD) and the mechanism of such role. METHODS: The mRNA expression of C5orf34 was analyzed using student's t-test based on the data obtained from TCGA database. Kaplan-Meier analysis was performed to evaluate the prognosis value of C5orf34. Chi-square (χ2) test was performed to analyze the correlation between C5orf34 expression and clinical features. The effect of C5orf34 siRNA on A549 and SPCA1 cells proliferation and migration were explored using CCK8 assay, wound healing assay and transwell assays, respectively. Western blot was performed to evaluate the expression of C5orf34, ERK, p-ERK, MEK and p-MEK. RESULTS: C5orf34 expression was enhanced in LAD and positively correlated with poor prognosis in patients with LAD. χ2 test revealed that C5orf34 expression was obviously associated with age (p = 0.016), Pathologic-Stage (p = 0.045) and Pathologic-N (p = 0.023). In addition, knockdown of C5orf34 significantly suppressed A549 and SPCA1 cells proliferation and motility (p < 0.01) in vitro. Moreover, by western blot analysis, we found that depleting C5orf34 remarkably reduced the ratio of p-MEK/MEK and p-ERK/ERK in A549 cells. CONCLUSION: Our results firstly revealed that C5orf34 might play a facilitating role in LAD development and progression by regulating MAPK signaling pathway. Furthermore, our data implied that C5orf34 may be a potential predictor and treatment target for LAD.


Assuntos
Adenocarcinoma de Pulmão/genética , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Neoplasias Pulmonares/genética , Sistema de Sinalização das MAP Quinases/genética , Células A549 , Adenocarcinoma de Pulmão/mortalidade , Adenocarcinoma de Pulmão/patologia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Técnicas de Silenciamento de Genes , Voluntários Saudáveis , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Regulação para Cima
10.
Phytochem Anal ; 29(1): 101-111, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28895207

RESUMO

INTRODUCTION: The tuberous roots of Stephania kwangsiensis, which contain bioactive alkaloids, are used as a traditional Chinese medicine. Overexploitation of the roots has made the plant increasingly rare, and the abundant leaves of the same plant may offer a potential alternative. However, there is insufficient phytochemical information for a comparison of alkaloid compositions in the two parts. OBJECTIVE: To characterise and compare the alkaloids in the leaves and roots of S. kwangsiensis. METHODS: The alkaloids in S. kwangsiensis were characterised using high pressure liquid chromatography coupled with positive electrospray ionisation quadrupole time-of-flight tandem mass spectrometry (HPLC-(+)ESI-QTOF-MS/MS). The alkaloid compositions in the leaves and roots were compared by visual inspection combined with principal component analysis (PCA) of the HPLC-MS data. RESULTS: Seventy-five alkaloids comprising aporphine-, proaporphine-, protoberberine-, benzylisoquinoline-, bisbenzylisoquinoline- and morphine-type alkaloids were identified or tentatively identified in the roots and leaves of S. kwangsiensis. Sixty-three of these alkaloids have not been previously reported in this species, and three have not been previously reported in the literature. The roots and leaves had similarities in alkaloid composition but differences in the peak intensities of most alkaloids. The PCA revealed that the samples were clustered into two distinct groups, which corresponded to leaves and roots. CONCLUSION: This study further clarified the chemical constituents in the roots of S. kwangsiensis, and revealed that diverse alkaloids were also present in the leaves. The comparative chemical profiling of the two parts provides useful information on their potential medicinal use. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Alcaloides/química , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Folhas de Planta/química , Raízes de Plantas/química , Stephania/química , Estrutura Molecular
11.
Phytochem Anal ; 27(3-4): 206-16, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27313158

RESUMO

INTRODUCTION: Plants in the genus Stephania can produce diverse bioactive alkaloids. Stephania hainanensis is a medicinal plant that contains effective alkaloids. However, only 10 alkaloids have been reported in this species. OBJECTIVE: To characterise the alkaloids in Stephania hainanensis using liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (LC-QTOF-MS/MS). METHODS: An LC-QTOF-MS/MS method was developed for structural characterisation of the alkaloids in Stephania hainanensis. The chromatographic separation was performed on a phenyl column with gradient elution, and the tandem mass spectra were obtained by using an electrospray ionisation (ESI) interface in positive ionisation mode. Compound identification was based on the exact masses, fragmentation pathways, retention behaviours and related botanical biogenesis. RESULTS: A total of 37 tetrahydroprotoberberine-, quaternary protoberberine-, aporphine-, proaporphine-, benzylisoquinoline- or bisbenzylisoquinoline-type alkaloids were identified or tentatively identified in a single LC run. Twenty-seven of these alkaloids, including the benzylisoquinoline-type of alkaloids, have not been previously reported in Stephania hainanensis. The possible fragmentation pathways of different types of alkaloids were proposed. Besides the general fragmentations, the characteristic losses of CH3 N = CH2 were observed for the benzylisoquinoline and aporphine alkaloids with two methyl groups on the nitrogen. CONCLUSION: The LC-QTOF-MS/MS method enabled profiling and rational, but tentative, identification of diverse alkaloids in Stephania hainanensis. The results obtained may be helpful for understanding the bioactivity of S. hainanensis and evaluating the quality of this plant. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Alcaloides/química , Benzilisoquinolinas/química , Cromatografia Líquida/métodos , Stephania/química , Espectrometria de Massas em Tandem/métodos , Alcaloides/isolamento & purificação , Aporfinas/química , Aporfinas/isolamento & purificação , Benzilisoquinolinas/isolamento & purificação , Alcaloides de Berberina/química , Alcaloides de Berberina/isolamento & purificação , Estrutura Molecular , Plantas Medicinais/química
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