Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
J Psycholinguist Res ; 53(1): 11, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319444

RESUMO

The study explored the role of verbal fluency in determining reading and comprehension skills in Bengali among 10-year old typically developing Bengali children. Robust correlations were found between semantic fluency and word reading (0.63) as well as semantic fluency and comprehension (0.70). Good correlation was found between letter fluency and comprehension (0.49), and, word reading and comprehension (0.62). The findings suggest that good word storing capacity and executive functions led to enhanced automaticity of retrieval and verbal fluency, which together with improved orthographic and phonological processing led to good word reading scores, contributing to lesser cognitive load thereby easing out the complex text comprehension task. Transcending narrow empirical base of reading theories derived from Western writing typologies delimited to orthographic depth and psycholinguistic grain size, the study contends that verbal fluency is another interesting variable determining the reading and comprehension skills in Bengali along with visuo-spatial complexity and complex phonology-orthography inconsistencies.


Assuntos
Compreensão , Leitura , Criança , Humanos , Função Executiva , Linguística , Psicolinguística
2.
Biochim Biophys Acta ; 1849(6): 697-708, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25725483

RESUMO

HOXC6 is a homeobox-containing gene associated with mammary gland development and is overexpressed in variety of cancers including breast and prostate cancers. Here, we have examined the expression of HOXC6 in breast cancer tissue, investigated its transcriptional regulation via estradiol (E2) and bisphenol-A (BPA, an estrogenic endocrine disruptor) in vitro and in vivo. We observed that HOXC6 is differentially over-expressed in breast cancer tissue. E2 induces HOXC6 expression in cultured breast cancer cells and in mammary glands of Sprague Dawley rats. HOXC6 expression is also induced upon exposure to BPA both in vitro and in vivo. Estrogen-receptor-alpha (ERα) and ER-coregulators such as MLL-histone methylases are bound to the HOXC6 promoter upon exposure to E2 or BPA and that resulted in increased histone H3K4-trimethylation, histone acetylation, and recruitment of RNA polymerase II at the HOXC6 promoter. HOXC6 overexpression induces expression of tumor growth factors and facilitates growth 3D-colony formation, indicating its potential roles in tumor growth. Our studies demonstrate that HOXC6, which is a critical player in mammary gland development, is upregulated in multiple cases of breast cancer, and is transcriptionally regulated by E2 and BPA, in vitro and in vivo.


Assuntos
Compostos Benzidrílicos/administração & dosagem , Neoplasias da Mama/genética , Epigenômica , Proteínas de Homeodomínio/biossíntese , Fenóis/administração & dosagem , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Disruptores Endócrinos/metabolismo , Estradiol/metabolismo , Receptor alfa de Estrogênio/genética , Estrogênios/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Homeodomínio/genética , Humanos , Células MCF-7 , Ratos
3.
Gene ; 897: 148055, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38043834

RESUMO

Brain derived neurotrophic factor (BDNF) is a major neurotransmitter that controls growth and maintenance of neurons and its misregulation is linked to neurodegeneration and human diseases. Estradiol (E2) is well-known to regulate the process of differentiation and plasticity of hippocampal neurons. Here we examined the mechanisms of BDNF gene regulation under basal conditions and under stimuli such as E2. Our results demonstrated that BDNF expression is induced by E2 in vitro in HT22 cells (hippocampal neuronal cells) and in vivo (in ovariectomized mouse brain under E2-treatment). Using chromatin immunoprecipitation assay, we demonstrated that estrogen receptors (ERα, ERß) were enriched at the BDNF promoter in presence of E2. Additionally, ER-coregulators (e.g., CBP/p300, MLL3), histone acetylation, H3K4-trimethylation, and RNA polymerase II levels were also elevated at the BDNF promoter in an E2-dependent manner. Additionally, under the basal conditions (in the absence of E2), the long noncoding RNA HOTAIR and its interacting partners PRC2 and LSD1 complexes binds to the promoter of BDNF and represses its expression. HOTAIR knockdown -relieves the repression resulting in elevation of BDNF expression. Further, levels of HOTAIR-interacting partners, EZH2 and LSD1 were reduced at the BDNF promoter upon HOTAIR-knockdown revealing that HOTAIR plays a regulatory role in BDNF gene expression by modulating promoter histone modifications. Additionally, we showed that E2 induced-BDNF expression is mediated by the displacement of silencing factors, EZH2 and LSD1 at BDNF promoter and subsequent recruitment of active transcription machinery. These results reveal the mechanisms of BDNF gene regulation under the basal condition and in presence of a positive regulator such as E2 in neuronal cells.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Estradiol , RNA Longo não Codificante , Animais , Humanos , Camundongos , Fator Neurotrófico Derivado do Encéfalo/genética , Linhagem Celular Tumoral , Estradiol/metabolismo , Expressão Gênica , Regulação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Histona Desmetilases/genética , RNA Longo não Codificante/metabolismo
4.
Sci Data ; 7(1): 220, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641714

RESUMO

Successful design of enhanced geothermal systems (EGSs) requires accurate numerical simulation of hydraulic stimulation processes in the subsurface. To ensure correct prediction, the underlying model assumptions and constitutive relationships of simulators need to be verified against experimental datasets. With the aim of generating laboratory-scale benchmark datasets, a state-of-the-art testing facility was developed, allowing for experiments under controlled conditions. Samples of size 30 cm × 30 cm × 45 cm were subjected to confining stresses while high-pressure fluid was injected into the sample through a pre-drilled borehole, where a saw-cut notch was used to initiate a penny-shaped fracture. Fracture growth and propagation was monitored by measuring pressure data and acoustic emissions detected using 32 seismic sensors. Subsequently, samples were split along the fracture plane to outline the created fracture marked by a red-dyed injection fluid. Finally, a 2D fracture contour was generated using photogrammetry. Presented datasets, accessible via a public repository, include experiments on granite and marble samples. They can be used for verifying and improving numerical codes for field stimulation designs.

5.
Front Genet ; 11: 592436, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33384715

RESUMO

HOXA5 is a homeobox-containing gene associated with the development of the lung, gastrointestinal tract, and vertebrae. Here, we investigate potential roles and the gene regulatory mechanism in HOXA5 in breast cancer cells. Our studies demonstrate that HOXA5 expression is elevated in breast cancer tissues and in estrogen receptor (ER)-positive breast cancer cells. HOXA5 expression is critical for breast cancer cell viability. Biochemical studies show that estradiol (E2) regulates HOXA5 gene expression in cultured breast cancer cells in vitro. HOXA5 expression is also upregulated in vivo in the mammary tissues of ovariectomized female rats. E2-induced HOXA5 expression is coordinated by ERs. Knockdown of either ERα or ERß downregulated E2-induced HOXA5 expression. Additionally, ER co-regulators, including CBP/p300 (histone acetylases) and MLL-histone methylases (MLL2, MLL3), histone acetylation-, and H3K4 trimethylation levels are enriched at the HOXA5 promoter in present E2. In summary, our studies demonstrate that HOXA5 is overexpressed in breast cancer and is transcriptionally regulated via estradiol in breast cancer cells.

6.
Sci Rep ; 8(1): 15670, 2018 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-30353135

RESUMO

Long noncoding RNAs (lncRNAs) are emerging as major regulators of a variety of cell signaling processes. Many lncRNAs are expressed in immune cells and appear to play critical roles in the regulation of immune response. Here, we have investigated the potential role of a well-known lncRNA, HOTAIR, in inflammatory and immune response. Our studies demonstrate that HOTAIR expression is induced in immune cells (macrophages) upon treatment with lipopolysaccharide (LPS). Knockdown of HOTAIR reduces NF-κB-mediated inflammatory gene and cytokine expression in macrophages. Inhibition of NF-κB resulted in down-regulation of LPS-induced expression of HOTAIR as well as IL-6 and iNOS expression. We further demonstrated that HOTAIR regulates activation of NF-κB and its target genes (IL-6 and iNOS) expression via facilitating the degradation of IκBα. HOTAIR knockdown reduces the expression of NF-κB target gene expression via inhibiting the recruitment of NF-κB and associated cofactors at the target gene promoters. Taken together, our findings suggest that HOTAIR is a critical player in NF-κB activation in macrophages suggesting its potential functions in inflammatory and immune response.


Assuntos
Citocinas/imunologia , Inflamação/imunologia , Lipopolissacarídeos/imunologia , Macrófagos/imunologia , RNA Longo não Codificante/imunologia , Animais , Citocinas/genética , Regulação da Expressão Gênica , Inflamação/genética , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/genética , NF-kappa B/imunologia , Células RAW 264.7 , RNA Longo não Codificante/genética
7.
Gene ; 629: 16-28, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28756022

RESUMO

Hypoxia signaling plays a critical role in tumor growth, angiogenesis, metastasis cancer, and aging. Under hypoxia, hypoxia-inducible factors (HIFs) are stabilized and they coordinate the process of hypoxia-induced gene expression and cell signaling leading to increased tumor growth. Recent studies indicate that non-coding RNAs which are closely associated with cancer are abnormally expressed under hypoxia. Here, we have investigated the transcriptional regulation of a cancer associated long non-coding RNA (lncRNA), HOTAIR, under hypoxic conditions. Our studies demonstrate that HOTAIR expression is upregulated under hypoxia in colon cancer and several other types of cancer cells. HOTAIR transcription is regulated by HIF1α which binds to the hypoxia response elements (HRE) present in the HOTAIR promoter under hypoxia. HIF1α knockdown results in decreased HOTAIR expression under hypoxia. Along with HIF1α, histone methylases MLL1 and histone acetylase p300 are enriched at the HOTAIR promoter under hypoxia. The levels of H3K4-trimethylation and histone acetylation are also enriched at the HOTAIR promoter. Furthermore, knockdown of MLL1 downregulated the hypoxia-induced HOTAIR expression, indicating key roles of MLL1 in hypoxia-induced HOTAIR expression. Overall, our studies demonstrate that histone methyl-transferase MLL1 coordinates with HIF1α and histone acetyltransferase p300 and regulate hypoxia-induced HOTAIR expression. The hypoxia-induced upregulation of HOTAIR expression may contribute to its roles in tumorigenesis.


Assuntos
Carcinogênese , Histona-Lisina N-Metiltransferase/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/metabolismo , Proteína de Leucina Linfoide-Mieloide/metabolismo , RNA Longo não Codificante/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Regiões Promotoras Genéticas , Transcrição Gênica , Fatores de Transcrição de p300-CBP/metabolismo
8.
Gene ; 590(2): 234-43, 2016 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-27182052

RESUMO

HOXB9 is a homeobox-containing gene that plays a key role in mammary gland development and is associated with breast and other types of cancer. Here, we demonstrate that HOXB9 expression is transcriptionally regulated by estradiol (E2), in vitro and in vivo. We also demonstrate that the endocrine disrupting chemical bisphenol-A (BPA) induces HOXB9 expression in cultured human breast cancer cells (MCF7) as well as in vivo in the mammary glands of ovariectomized (OVX) rats. Luciferase assay showed that estrogen-response-elements (EREs) in the HOXB9 promoter are required for BPA-induced expression. Estrogen-receptors (ERs) and ER-co-regulators such as MLL-histone methylase (MLL3), histone acetylases, CBP/P300, bind to the HOXB9 promoter EREs in the presence of BPA, modify chromatin (histone methylation and acetylation) and lead to gene activation. In summary, our results demonstrate that BPA exposure, like estradiol, increases HOXB9 expression in breast cells both in vitro and in vivo through a mechanism that involves increased recruitment of transcription and chromatin modification factors.


Assuntos
Compostos Benzidrílicos/toxicidade , Neoplasias da Mama/genética , Disruptores Endócrinos/toxicidade , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Homeodomínio/genética , Fenóis/toxicidade , Animais , Sequência de Bases , Variações do Número de Cópias de DNA/genética , Feminino , Proteínas de Homeodomínio/metabolismo , Humanos , Células MCF-7 , Glândulas Mamárias Animais/patologia , Modelos Biológicos , Ovariectomia , Regiões Promotoras Genéticas , Ratos Sprague-Dawley , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Elementos de Resposta/genética
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa