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1.
Bioinformatics ; 40(1)2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38216534

RESUMO

MOTIVATION: Transcription factor binding sites (TFBS) are regulatory elements that have significant impact on transcription regulation and cell fate determination. Canonical motifs, biological experiments, and computational methods have made it possible to discover TFBS. However, most existing in silico TFBS prediction models are solely DNA-based, and are trained and utilized within the same biosample, which fail to infer TFBS in experimentally unexplored biosamples. RESULTS: Here, we propose TFBS prediction by modified TransFormer (TFTF), a multimodal deep language architecture which integrates multiomics information in epigenetic studies. In comparison to existing computational techniques, TFTF has state-of-the-art accuracy, and is also the first approach to accurately perform genome-wide detection for cell-type and species-specific TFBS in experimentally unexplored biosamples. Compared to peak calling methods, TFTF consistently discovers true TFBS in threshold tuning-free way, with higher recalled rates. The underlying mechanism of TFTF reveals greater attention to the targeted TF's motif region in TFBS, and general attention to the entire peak region in non-TFBS. TFTF can benefit from the integration of broader and more diverse data for improvement and can be applied to multiple epigenetic scenarios. AVAILABILITY AND IMPLEMENTATION: We provide a web server (https://tftf.ibreed.cn/) for users to utilize TFTF model. Users can train TFTF model and discover TFBS with their own data.


Assuntos
Genoma , Multiômica , Sítios de Ligação , Ligação Proteica , Fatores de Transcrição/metabolismo , Biologia Computacional/métodos
2.
J Med Virol ; 96(6): e29762, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38923563

RESUMO

Functional cure of hepatitis B virus (HBV) is an optimal treatment goal for chronic hepatitis B, with the loss of hepatitis B surface antigen (HBsAg) being a crucial indicator. However, the adequacy of HBsAg loss for evaluating functional cure of HBV in patients co-infected with HBV/human immunodeficiency virus (HIV) remains controversial. In this study, we measured HBV pregenomic RNA (pgRNA), a potential biomarker that correlates with covalently closed circular DNA, in the frozen plasma of 98 patients with HBsAg loss from a large HIV/HBV co-infection cohort in Guangzhou, China. HBV pgRNA was still detected in 43.9% (44/98) of the patients, suggesting active HBV replication in individuals with HBsAg loss. Our observations imply that HBsAg loss may not be a reliable predictor of HBV functional cure in cases of HIV/HBV co-infection.


Assuntos
Biomarcadores , Coinfecção , Infecções por HIV , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Hepatite B Crônica , RNA Viral , Humanos , Infecções por HIV/virologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Antígenos de Superfície da Hepatite B/sangue , Coinfecção/virologia , Masculino , Vírus da Hepatite B/genética , Feminino , Adulto , RNA Viral/sangue , RNA Viral/genética , Biomarcadores/sangue , Pessoa de Meia-Idade , Hepatite B Crônica/virologia , Hepatite B Crônica/complicações , China , DNA Viral/sangue , Replicação Viral , Estudos de Coortes , RNA
3.
Br J Clin Pharmacol ; 89(12): 3659-3668, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37464978

RESUMO

AIMS: This study evaluated the effects of SHR0302 on the pharmacokinetics of cytochrome P450 (CYP) probe substrates. METHODS: We performed a single-centre, open-label, three-period drug-drug interaction (DDI) study in 24 healthy subjects (NCT05392127). Subjects received a single oral dose of 5 mg warfarin (CYP2C9), 20 mg omeprazole (CYP2C19) and 15 mg midazolam (CYP3A4) on Days 1, 8 and 22, and received 0.5 mg repaglinide (CYP2C8) on Days 7, 14 and 28. Multiple oral doses of 8 mg SHR0302 were administered once daily from Day 8 to Day 28. RESULTS: The exposure of S-warfarin and repaglinide were comparable before and after SHR0302 administration. AUC of midazolam was not affected by SHR0302, whereas the administration of SHR0302 slightly decreased the Cmax of midazolam by 7.6% (single dose) and 15.7% (once daily for 14 days). The AUC0-t , AUC0-inf , and Cmax of omeprazole were slightly decreased after a single dose of SHR0302 by 19.2%, 21.8% and 23.5%, respectively. In the presence of SHR0302 for 14 days, the AUC0-t , AUC0-inf , and Cmax of omeprazole were marginally reduced by 3.0%, 16.4% and 8.3%, respectively. According to the induction mechanism of the CYP enzyme, for the investigation of the induction effect, the results of multiple administrations of the perpetrator were more reliable than those of the single dose. CONCLUSIONS: The results demonstrated that co-administration of SHR0302 8 mg once daily is unlikely to have a clinically meaningful effect on the exposure of drugs metabolized by CYP3A4, CYP2C8, CYP2C9 and CYP2C19 in healthy subjects.


Assuntos
Citocromo P-450 CYP3A , Midazolam , Humanos , Citocromo P-450 CYP3A/metabolismo , Midazolam/farmacocinética , Citocromo P-450 CYP2C8/metabolismo , Citocromo P-450 CYP2C9 , Varfarina , Citocromo P-450 CYP2C19/genética , Interações Medicamentosas , Sistema Enzimático do Citocromo P-450/metabolismo , Omeprazol/farmacocinética , Voluntários Saudáveis
4.
Inorg Chem ; 62(6): 2784-2792, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36705969

RESUMO

Efficient electrocatalysts require not only a tunable electronic structure but also great active site accessibility and favorable mass transfer. Here, a two-dimensional/three-dimensional (2D/3D) hierarchical electrocatalyst consisting of Co(OH)2-CeO2 nanosheet-decorated Co dendrites is proposed, named as Co(OH)2-CeO2/Co. Based on the strong electronic interaction of the Co(OH)2-CeO2 heterojunction, the electronic structure of the Co site is optimized, which facilitates the adsorption of intermediates and the dissociation of H2O. Moreover, the open 2D/3D structure formed by introducing the Co substrate further reduces the accumulation of heterogeneous nanosheets and promotes the radial diffusion of the electrolyte, significantly improving the utilization of active sites and shortening the electron transfer pathway. In addition, the superhydrophilic/superaerophobic interface achieved by constructing the hierarchical micro-nanostructure is beneficial to electrolyte infiltration and bubble desorption, thus ensuring favorable mass transfer. Therefore, Co(OH)2-CeO2/Co exhibits an excellent overall water-splitting activity in alkaline solution.

5.
Mol Ther ; 30(2): 898-914, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-34400329

RESUMO

Heart failure is a leading cause of fatality in Duchenne muscular dystrophy (DMD) patients. Previously, we discovered that cardiac and skeletal-muscle-enriched CIP proteins play important roles in cardiac function. Here, we report that CIP, a striated muscle-specific protein, participates in the regulation of dystrophic cardiomyopathy. Using a mouse model of human DMD, we found that deletion of CIP leads to dilated cardiomyopathy and heart failure in young, non-syndromic mdx mice. Conversely, transgenic overexpression of CIP reduces pathological dystrophic cardiomyopathy in old, syndromic mdx mice. Genome-wide transcriptome analyses reveal that molecular pathways involving fibrogenesis and oxidative stress are affected in CIP-mediated dystrophic cardiomyopathy. Mechanistically, we found that CIP interacts with dystrophin and calcineurin (CnA) to suppress the CnA-Nuclear Factor of Activated T cells (NFAT) pathway, which results in decreased expression of Nox4, a key component of the oxidative stress pathway. Overexpression of Nox4 accelerates the development of dystrophic cardiomyopathy in mdx mice. Our study indicates CIP is a modifier of dystrophic cardiomyopathy and a potential therapeutic target for this devastating disease.


Assuntos
Cardiomiopatias , Cardiomiopatia Dilatada , Distrofia Muscular de Duchenne , Animais , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Cardiomiopatia Dilatada/genética , Proteínas Correpressoras , Distrofina/metabolismo , Coração , Humanos , Camundongos , Camundongos Endogâmicos mdx , Distrofia Muscular de Duchenne/patologia , Proteínas Nucleares
6.
Multivariate Behav Res ; 58(5): 877-893, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36496553

RESUMO

Redundancy analysis (RA) is a multivariate method that maximizes the mean variance of a set of criterion variables explained by a small number of redundancy variates (i.e., linear combinations of a set of predictor variables). However, two challenges exist in RA. First, inferential information for the RA estimates might not be readily available. Second, the existing methods addressing the dimensionality problem in RA are limited for various reasons. To aid the applications of RA, we propose a direct covariance structure modeling approach to RA. The proposed approach (1) provides inferential information for the RA estimates, and (2) allows the researcher to use a simple yet practical criterion to address the dimensionality problem in RA. We illustrate our approach with an artificial example, validate some standard error estimates by simulations, and demonstrate our new criterion in a real example. Finally, we conclude with future research topics.

7.
Behav Res Methods ; 54(2): 922-940, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34357540

RESUMO

Large-scale surveys are common in social and behavioral science research. Missing data often occur at item levels due to nonresponses or planned missing data designs. In practice, the item scores are typically aggregated into scale scores (i.e., sum or mean scores) for further analyses. Although several strategies to handle item-level missing data have been proposed, most of them are not easy to implement, especially for applied researchers. Using Monte Carlo simulations, we examined a practical hybrid approach to deal with item-level missing data in Likert scale items with a varying number of categories (i.e., four, five, and seven) and missing data mechanisms. Specifically, the examined approach first uses proration to calculate the scale scores for a participant if a certain proportion of item scores is available (a cutoff criterion of proration) and then use full information maximum likelihood to deal with missing data at the scale level when scale scores cannot be computed due to the selected proration cutoff criterion. Our simulation results showed that the hybrid approach was generally acceptable when the missing data were randomly spread over the items, even when they had different thresholds/means and loadings, with caution to be taken when the missingness is determined by one of the scale items. Based on the results, we recommend using the cutoff of 30% or 40% for proration when the sample size is small and the cutoff of 40% or 50% when the sample size is moderate or large.


Assuntos
Pesquisa Comportamental , Simulação por Computador , Humanos , Tamanho da Amostra , Inquéritos e Questionários
8.
Bull Environ Contam Toxicol ; 109(4): 651-658, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35908225

RESUMO

Contaminated soils have caused serious harm to human health and the ecological environment due to the high toxicity of organic and inorganic pollutants, which has attracted extensive attention in recent years. Because of its low cost, simple operation and high efficiency, soil washing technology is widely used to permanently remove various pollutants in contaminated soils and is considered to be the most promising remediation technology. This review summarized the recent developments in the field of soil washing technology and discusses the application of conventional washing agents, advanced emerging washing agents, the recycling of washing effluents and the combination of soil washing and other remediation technologies. Overall, the findings provide a comprehensive understanding of soil washing technology and suggest some potential improvements from a scientific and practical point of view.


Assuntos
Recuperação e Remediação Ambiental , Metais Pesados , Poluentes do Solo , Poluição Ambiental , Humanos , Metais Pesados/análise , Solo , Poluentes do Solo/análise , Tecnologia
9.
Cancer Control ; 28: 1073274821989307, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33593091

RESUMO

OBJECTIVE: To evaluated the oncologic outcomes associated with platinum-based adjuvant chemotherapy following concurrent chemoradiotherapy (CCRT) in the management of patients with locally advanced cervical cancer (LACC). METHODS: A total of 695 patients with FIGO stage IB2, IIA2, IIB-IVA LACC treated at 6 medical facilities were enrolled and divided into 2 groups: 478 were assigned to CCRT alone (CCRT group) and 217 to adjuvant chemotherapy after CCRT (CCRT-ACT group). The treatment outcomes were retrospectively compared and reported after the propensity score matching (PSM) analysis. RESULTS: With a median follow-up of 56.4 months, no statistically significant differences were found in overall survival (OS), disease-free survival (DFS), progression-free survival (PFS) and distance metastasis-free survival (DMFS) between 2 groups. In CCRT-ACT group, patients with lymph nodes involvement or squamous cell carcinoma (SCC) had significantly longer DMFS, but no significant benefit in survival outcomes were observed with more than 2 cycles of adjuvant chemotherapy. Moreover, patients with a high level of CA125 (>20.5U/mL) or SCC-Ag (>22.8µg/L) had a relatively better DFS or PFS, and grade 3-4 acute hematological toxicity, late urinary and lower gastrointestinal complications and diarrhea symptom were more frequent in CCRT-ACT group. CONCLUSIONS: Adjuvant chemotherapy after CCRT has a potential role in further improving disease control for LACC patients with lymph nodal-metastasis or SCC with a high level of CA125 or SCC-Ag. Due to increased treatment-related complications and diarrhea symptom affecting the quality of life, post-CCRT adjuvant chemotherapy with excessive cycles was not be considered as the most appropriate choice in general.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia , Quimioterapia Adjuvante , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Carboplatina/uso terapêutico , Cisplatino/uso terapêutico , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia
10.
Nonlinear Dyn ; 105(3): 2757-2773, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34334951

RESUMO

Multiple new variants of SARS-CoV-2 have been identified as the COVID-19 pandemic spreads across the globe. However, most epidemic models view the virus as static and unchanging and thus fail to address the consequences of the potential evolution of the virus. Here, we built a competitive susceptible-infected-removed (coSIR) model to simulate the competition between virus strains of differing severities or transmissibility under various virus control policies. The coSIR model predicts that although the virus is extremely unlikely to evolve into a "super virus" that causes an increased fatality rate, virus variants with less severe symptoms can lead to potential new outbreaks and can cost more lives over time. The present model also demonstrates that the protocols restricting the transmission of the virus, such as wearing masks and social distancing, are the most effective strategy in reducing total mortality. A combination of adequate testing and strict quarantine is a powerful alternative to policies such as mandatory stay-at-home orders, which may have an enormous negative impact on the economy. In addition, building Mobile Cabin Hospitals can be effective and efficient in reducing the mortality rate of highly infectious virus strains. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11071-021-06705-8.

11.
Cancer Immunol Immunother ; 69(5): 779-788, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32052078

RESUMO

Dendritic cells are crucial for the initiation and regulation of immune responses against cancer and pathogens. DCs are heterogeneous and highly specialized antigen-presenting cells. Human DCs comprise several subsets with different phenotypes and functional properties. In the steady state, human DC subsets have been well studied. However, the components of DC subsets and their immune functions during the inflamed setting are poorly understood. We identified and characterized DC subsets in the malignant pleural effusions of NSCLC patients. We analyzed the capacity of these DC subsets to induce T-cell differentiation. We observed the presence of inflammatory DCs (infDCs) and macrophages in the malignant pleural effusions of NSCLC patients, as identified by the CD11C+HLA-DR+CD16-BDCA1+ and CD11C+HLA-DR+CD16+BDCA1- phenotypes, respectively. InfDCs represented approximately 1% of the total light-density cells in the pleural effusion and were characterized by the expression of CD206, CD14, CD11b, and CD1α, which were absent on blood DCs. InfDCs also expressed CD80, although at a low level. As infDCs did not express CD40, CD83 and CD275, they remained functionally immature. We found that TLR agonists promoted the maturation of infDCs. Compared with macrophages, infDCs had a weaker capacity to phagocytose necrotic tumor cell lysates. However, only infDCs induced autologous memory CD4+ T-cell differentiation into Th1 cells. For the first time, we found that infDCs were present in the malignant pleural effusions of NSCLC patients. We conclude that infDCs represent a distinct human DC subset and induce Th1 cell differentiation in the presence of TLR agonists.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/imunologia , Células Dendríticas/imunologia , Neoplasias Pulmonares/patologia , Derrame Pleural Maligno/imunologia , Células Th1/imunologia , Carcinoma Pulmonar de Células não Pequenas/secundário , Comunicação Celular/efeitos dos fármacos , Comunicação Celular/imunologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Células Dendríticas/metabolismo , Humanos , Imidazóis/farmacologia , Lipopolissacarídeos/farmacologia , Neoplasias Pulmonares/imunologia , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Fagocitose/efeitos dos fármacos , Fagocitose/imunologia , Cultura Primária de Células , Receptores Toll-Like/agonistas , Receptores Toll-Like/metabolismo , Células Tumorais Cultivadas
12.
Circ Res ; 122(1): 74-87, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29021295

RESUMO

RATIONALE: Although mitochondrial diseases often cause abnormal myocardial development, the mechanisms by which mitochondria influence heart growth and function are poorly understood. OBJECTIVE: To investigate these disease mechanisms, we studied a genetic model of mitochondrial dysfunction caused by inactivation of Tfam (transcription factor A, mitochondrial), a nuclear-encoded gene that is essential for mitochondrial gene transcription and mitochondrial DNA replication. METHODS AND RESULTS: Tfam inactivation by Nkx2.5Cre caused mitochondrial dysfunction and embryonic lethal myocardial hypoplasia. Tfam inactivation was accompanied by elevated production of reactive oxygen species (ROS) and reduced cardiomyocyte proliferation. Mosaic embryonic Tfam inactivation confirmed that the block to cardiomyocyte proliferation was cell autonomous. Transcriptional profiling by RNA-seq demonstrated the activation of the DNA damage pathway. Pharmacological inhibition of ROS or the DNA damage response pathway restored cardiomyocyte proliferation in cultured fetal cardiomyocytes. Neonatal Tfam inactivation by AAV9-cTnT-Cre caused progressive, lethal dilated cardiomyopathy. Remarkably, postnatal Tfam inactivation and disruption of mitochondrial function did not impair cardiomyocyte maturation. Rather, it elevated ROS production, activated the DNA damage response pathway, and decreased cardiomyocyte proliferation. We identified a transient window during the first postnatal week when inhibition of ROS or the DNA damage response pathway ameliorated the detrimental effect of Tfam inactivation. CONCLUSIONS: Mitochondrial dysfunction caused by Tfam inactivation induced ROS production, activated the DNA damage response, and caused cardiomyocyte cell cycle arrest, ultimately resulting in lethal cardiomyopathy. Normal mitochondrial function was not required for cardiomyocyte maturation. Pharmacological inhibition of ROS or DNA damage response pathways is a potential strategy to prevent cardiac dysfunction caused by some forms of mitochondrial dysfunction.


Assuntos
Cardiomiopatias/metabolismo , Proliferação de Células/fisiologia , Mitocôndrias Cardíacas/metabolismo , Miócitos Cardíacos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Cardiomiopatias/patologia , Células Cultivadas , Dano ao DNA/fisiologia , Camundongos , Camundongos Transgênicos , Mitocôndrias Cardíacas/patologia , Miócitos Cardíacos/patologia
13.
Clin Exp Rheumatol ; 38(5): 841-847, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31820726

RESUMO

OBJECTIVES: Early identification of patients with rheumatoid arthritis (RA) is essential to allow prompt therapy. In this study, we aimed to evaluate the performance of the newly proposed ERA criteria, compared to the 1987 ACR and 2010 ACR/EULAR criteria in an international multicentre study. METHODS: A total of 606 patients with disease duration ≤2 years and age ≥16 years who were diagnosed as RA or non-RA were enrolled from China, Sweden and India. The clinical and laboratory parameters were recorded. We compared the sensitivity, specificity, predictive value, likelihood ratio (LR), and the area under the ROC curve (AUC) of three criteria in these cohorts. Concordance between the three criteria was calculated with the Kappa coefficient. RESULTS: Three hundred and twelve RA and 294 non-RA patients were included. The Early Rheumatoid Arthritis (ERA) criteria had significantly higher specificity compared to the 2010 ACR/ EULAR criteria (83.7% vs. 78.2%, p=0.02) and sensitivity were similar (79.2% vs. 78.5%, p=0.883). In comparison with the 1987 ACR criteria, the ERA criteria had higher sensitivity (79.2% vs. 54.5%, p<0.001) but lower specificity (83.7% vs. 89.1%, p<0.001), and the AUC of the ERA criteria (0.878) was comparable to the 2010 ACR/EULAR criteria (0.849) and higher than the 1987 ACR criteria (0.791, p<0.0001). Patients from the three countries, seronegative and very early arthritis cohorts yielded consistent results. CONCLUSIONS: The ERA criteria demonstrate a better performance across ethnics in early RA diagnosis, and is more feasible in daily practice.


Assuntos
Artrite Reumatoide , Área Sob a Curva , Artrite Reumatoide/diagnóstico , Humanos , Índia , Sensibilidade e Especificidade , Suécia
14.
Genomics ; 111(1): 17-23, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-27453286

RESUMO

To develop accurate prognostic models is one of the biggest challenges in "omics"-based cancer research. Here, we propose a novel computational method for identifying dysregulated gene subnetworks as biomarkers to predict cancer recurrence. Applying our method to the DNA methylome of endometrial cancer patients, we identified a subnetwork consisting of differentially methylated (DM) genes, and non-differentially methylated genes, termed Epigenetic Connectors (EC), that are topologically important for connecting the DM genes in a protein-protein interaction network. The ECs are statistically significantly enriched in well-known tumorgenesis and metastasis pathways, and include known epigenetic regulators. Importantly, combining the DMs and ECs as features using a novel random walk procedure, we constructed a support vector machine classifier that significantly improved the prediction accuracy of cancer recurrence and outperformed several alternative methods, demonstrating the effectiveness of our network-based approach.


Assuntos
Algoritmos , Biomarcadores Tumorais , Metilação de DNA , Neoplasias do Endométrio , Recidiva Local de Neoplasia , Ilhas de CpG , DNA de Neoplasias , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Epigenômica , Feminino , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Modelos Genéticos , Prognóstico , Domínios e Motivos de Interação entre Proteínas , Análise de Sequência de DNA
15.
Development ; 143(3): 492-503, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26700681

RESUMO

Maternally expressed proteins function in vertebrates to establish the major body axes of the embryo and to establish a pre-pattern that sets the stage for later-acting zygotic signals. This pre-patterning drives the propensity of Xenopus animal cap cells to adopt neural fates under various experimental conditions. Previous studies found that the maternally expressed transcription factor, encoded by the Xenopus achaete scute-like gene ascl1, is enriched at the animal pole. Asc1l is a bHLH protein involved in neural development, but its maternal function has not been studied. Here, we performed a series of gain- and loss-of-function experiments on maternal ascl1, and present three novel findings. First, Ascl1 is a repressor of mesendoderm induced by VegT, but not of Nodal-induced mesendoderm. Second, a previously uncharacterized N-terminal domain of Ascl1 interacts with HDAC1 to inhibit mesendoderm gene expression. This N-terminal domain is dispensable for its neurogenic function, indicating that Ascl1 acts by different mechanisms at different times. Ascl1-mediated repression of mesendoderm genes was dependent on HDAC activity and accompanied by histone deacetylation in the promoter regions of VegT targets. Finally, maternal Ascl1 is required for animal cap cells to retain their competence to adopt neural fates. These results establish maternal Asc1l as a key factor in establishing pre-patterning of the early embryo, acting in opposition to VegT and biasing the animal pole to adopt neural fates. The data presented here significantly extend our understanding of early embryonic pattern formation.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Endoderma/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Histona Desacetilases/metabolismo , Mesoderma/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas com Domínio T/metabolismo , Proteínas de Xenopus/metabolismo , Xenopus laevis/embriologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/química , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Ectoderma/efeitos dos fármacos , Ectoderma/embriologia , Ectoderma/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Endoderma/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Mesoderma/efeitos dos fármacos , Morfolinos/farmacologia , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Neurogênese/efeitos dos fármacos , Neurogênese/genética , Estrutura Terciária de Proteína , Proteínas de Xenopus/química , Proteínas de Xenopus/genética , Xenopus laevis/genética
16.
Multivariate Behav Res ; 54(2): 192-223, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30661402

RESUMO

The mathematical connection between canonical correlation analysis (CCA) and covariance structure analysis was first discussed through the Multiple Indicators and Multiple Causes (MIMIC) approach. However, the MIMIC approach has several technical and practical challenges. To address these challenges, a comprehensive COSAN modeling approach is proposed. Specifically, we define four COSAN-CCA models to correspond with four possible combinations of the data to be analyzed and the unique parameters to be estimated. In terms of the data, one can analyze either the unstandardized or standardized variables. In terms of the unique parameters, one can estimate either the weights or loadings. Besides the unique parameters of each COSAN-CCA model, all four COSAN-CCA models also estimate the canonical correlations as their common parameters. Taken together, the four COSAN-CCA models provide the correct point estimates and standard error estimates for all commonly used CCA parameters. Two numeric examples are used to compare the standard error estimates obtained from the MIMIC approach and the COSAN modeling approach. Moreover, the standard error estimates from the COSAN modeling approach are validated by a simulation study and the asymptotic theory. Finally, software implementation and future extensions are discussed.


Assuntos
Algoritmos , Modelos Estatísticos , Análise Multivariada , Humanos
17.
Circ Res ; 116(1): 35-45, 2015 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-25249570

RESUMO

RATIONALE: Yes-associated protein (YAP), the nuclear effector of Hippo signaling, regulates cellular growth and survival in multiple organs, including the heart, by interacting with TEA (transcriptional enhancer activator)-domain sequence-specific DNA-binding proteins. Recent studies showed that YAP stimulates cardiomyocyte proliferation and survival. However, the direct transcriptional targets through which YAP exerts its effects are poorly defined. OBJECTIVE: To identify direct YAP targets that mediate its mitogenic and antiapoptotic effects in the heart. METHODS AND RESULTS: We identified direct YAP targets by combining differential gene expression analysis in YAP gain- and loss-of-function with genome-wide identification of YAP-bound loci using chromatin immunoprecipitation and high throughput sequencing. This screen identified Pik3cb, encoding p110ß, a catalytic subunit of phosphoinositol-3-kinase, as a candidate YAP effector that promotes cardiomyocyte proliferation and survival. YAP and TEA-domain occupied a conserved enhancer within the first intron of Pik3cb, and this enhancer drove YAP-dependent reporter gene expression. Yap gain- and loss-of-function studies indicated that YAP is necessary and sufficient to activate the phosphoinositol-3-kinase-Akt pathway. Like Yap, Pik3cb gain-of-function stimulated cardiomyocyte proliferation, and Pik3cb knockdown dampened YAP mitogenic activity. Reciprocally, impaired heart function in Yap loss-of-function was significantly rescued by adeno-associated virus-mediated Pik3cb expression. CONCLUSIONS: Pik3cb is a crucial direct target of YAP, through which the YAP activates phosphoinositol-3-kinase-AKT pathway and regulates cardiomyocyte proliferation and survival.


Assuntos
Proteínas Reguladoras de Apoptose/biossíntese , Proliferação de Células/fisiologia , Classe Ib de Fosfatidilinositol 3-Quinase/biossíntese , Miócitos Cardíacos/fisiologia , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Proto-Oncogênicas c-akt/biossíntese , Animais , Animais Recém-Nascidos , Proteínas Reguladoras de Apoptose/genética , Sequência de Bases , Sobrevivência Celular/fisiologia , Células Cultivadas , Classe Ib de Fosfatidilinositol 3-Quinase/genética , Via de Sinalização Hippo , Camundongos , Dados de Sequência Molecular , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Ratos , Transdução de Sinais/fisiologia , Proteínas de Sinalização YAP
18.
Mol Carcinog ; 55(11): 1867-1875, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27696538

RESUMO

Aberrant methylation of DNA is a common event in the development of cancers, including squamous cell carcinoma (SCC) of the human esophagus. In the present study, we determined: (a) whether aberrant DNA methylation also occurs in the development of N-nitrosomethylbenzylamine (NMBA)-induced tumorigenesis in the rat esophagus, a model of human esophageal SCC; and (b) if so, whether dietary black raspberries (BRBs) are capable of preventing this aberrant DNA methylation. A diet containing 5% BRBs inhibited the development of NMBA-induced tumors in the rat esophagus. This inhibition was associated with reduced mRNA levels of the DNA methyltransferases, Dnmt1 and Dnmt3b, in both dysplastic lesions and in papillomas of the esophagus. In addition, promoter methylation of Sfrp4, a WNT pathway antagonist, was significantly reduced by the berry diet, and this was associated with decreased nuclear localization of ß-CATENIN and reduced expression of c-MYC protein in NMBA-treated esophagi. Decreased promoter methylation of Sfrp4 correlated with decreased expression of Dmnt3b and, ultimately, with increased Sfrp4 mRNA expression. This suggests that epigenetic alterations in NMBA-induced rat esophageal tumorigenesis recapitulate epigenetic events in human esophageal SCC, and that BRBs could be useful in preventing the aberrant DNA methylation involved in the development of human esophageal SCC. © 2015 Wiley Periodicals, Inc.


Assuntos
Carcinoma de Células Escamosas/dietoterapia , DNA (Citosina-5-)-Metiltransferases/genética , Dimetilnitrosamina/análogos & derivados , Neoplasias Esofágicas/dietoterapia , Extratos Vegetais/administração & dosagem , Proteínas Proto-Oncogênicas/genética , Rubus/química , Animais , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/genética , DNA (Citosina-5-)-Metiltransferase 1 , Metilação de DNA/efeitos dos fármacos , Dimetilnitrosamina/efeitos adversos , Epigênese Genética/efeitos dos fármacos , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Extratos Vegetais/farmacologia , Ratos , Via de Sinalização Wnt/efeitos dos fármacos , DNA Metiltransferase 3B
19.
Circ Res ; 115(3): 354-63, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24833660

RESUMO

RATIONALE: Yes-associated protein (YAP), the terminal effector of the Hippo signaling pathway, is crucial for regulating embryonic cardiomyocyte proliferation. OBJECTIVE: We hypothesized that YAP activation after myocardial infarction (MI) would preserve cardiac function and improve survival. METHODS AND RESULTS: We used a cardiac-specific, inducible expression system to activate YAP in adult mouse heart. Activation of YAP in adult heart promoted cardiomyocyte proliferation and did not deleteriously affect heart function. Furthermore, YAP activation after MI preserved heart function and reduced infarct size. Using adeno-associated virus subtype 9 (AAV9) as a delivery vector, we expressed human YAP (hYAP) in the adult murine myocardium immediately after MI. We found that AAV9:hYAP significantly improved cardiac function and mouse survival. AAV9:hYAP did not exert its salutary effects by reducing cardiomyocyte apoptosis. Rather, AAV9:hYAP stimulated adult cardiomyocyte proliferation. Gene expression profiling indicated that AAV9:hYAP stimulated expression of cell cycle genes and promoted a less mature cardiac gene expression signature. CONCLUSIONS: Cardiac-specific YAP activation after MI mitigated myocardial injury, improved cardiac function, and enhanced survival. These findings suggest that therapeutic activation of YAP or its downstream targets, potentially through AAV-mediated gene therapy, may be a strategy to improve outcome after MI.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/fisiologia , Fosfoproteínas/genética , Fosfoproteínas/fisiologia , Animais , Apoptose/genética , Apoptose/fisiologia , Cardiomegalia , Proliferação de Células , Sobrevivência Celular/fisiologia , Dependovirus/genética , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Transgênicos , Contração Miocárdica/fisiologia , Infarto do Miocárdio/genética , Infarto do Miocárdio/mortalidade , Miócitos Cardíacos/citologia , Cadeias Pesadas de Miosina/genética , Regeneração/genética , Regeneração/fisiologia , Taxa de Sobrevida , Fatores de Transcrição , Transcriptoma , Proteínas de Sinalização YAP
20.
J Immunol ; 193(9): 4381-90, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25274529

RESUMO

Mesenchymal stem cells (MSCs) are useful in tissue repair but also possess immunomodulatory properties. Murine and uncontrolled human trials suggest efficacy of MSCs in treating lupus. Autologous cells are preferable; however, recent studies suggest that lupus-derived MSCs lack efficacy in treating disease. Thus, the optimum derivation of MSCs for use in lupus is unknown. It is also unknown which in vitro assays of MSC function predict in vivo efficacy. The objectives for this study were to provide insight into the optimum source of MSCs and to identify in vitro assays that predict in vivo efficacy. We derived MSCs from four umbilical cords, four healthy bone marrows (BMs), and four lupus BMs. In diseased MRL/lpr mice, MSCs from healthy BM and umbilical cords significantly decreased renal disease, whereas lupus BM MSCs only delayed disease. Current in vitro assays did not differentiate efficacy of the different MSCs. However, differences in MSC efficacy were observed in B cell proliferation assays. Our results suggest that autologous MSCs from lupus patients are not effective in treating disease. Furthermore, standard in vitro assays for MSC licensing are not predictive of in vivo efficacy, whereas inhibiting B cell proliferation appears to differentiate effective MSCs from ineffective MSCs.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Adulto , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Medula Óssea/imunologia , Medula Óssea/metabolismo , Medula Óssea/patologia , Diferenciação Celular , Citocinas/biossíntese , Modelos Animais de Doenças , Feminino , Expressão Gênica , Humanos , Imunofenotipagem , Mediadores da Inflamação/metabolismo , Rim/imunologia , Rim/patologia , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/metabolismo , Lúpus Eritematoso Sistêmico/mortalidade , Lúpus Eritematoso Sistêmico/patologia , Lúpus Eritematoso Sistêmico/terapia , Masculino , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos MRL lpr , Fenótipo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Doadores de Tecidos , Resultado do Tratamento
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