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1.
Cell ; 185(4): 581-584, 2022 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-35180387

RESUMEN

In a recent issue of Nature, Kagawa et al. reported a highly efficient and robust protocol for generating human blastoids from naive human pluripotent stem cells. The blastoids resemble human blastocysts, follow the sequential lineage specification of blastocyst development, and can attach to endometrial cells with the polar trophectoderm to model implantation.


Asunto(s)
Desarrollo Embrionario , Células Madre Pluripotentes , Blastocisto , Implantación del Embrión , Humanos
2.
Cell ; 179(3): 687-702.e18, 2019 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-31626770

RESUMEN

A single mouse blastomere from an embryo until the 8-cell stage can generate an entire blastocyst. Whether laboratory-cultured cells retain a similar generative capacity remains unknown. Starting from a single stem cell type, extended pluripotent stem (EPS) cells, we established a 3D differentiation system that enabled the generation of blastocyst-like structures (EPS-blastoids) through lineage segregation and self-organization. EPS-blastoids resembled blastocysts in morphology and cell-lineage allocation and recapitulated key morphogenetic events during preimplantation and early postimplantation development in vitro. Upon transfer, some EPS-blastoids underwent implantation, induced decidualization, and generated live, albeit disorganized, tissues in utero. Single-cell and bulk RNA-sequencing analysis revealed that EPS-blastoids contained all three blastocyst cell lineages and shared transcriptional similarity with natural blastocysts. We also provide proof of concept that EPS-blastoids can be generated from adult cells via cellular reprogramming. EPS-blastoids provide a unique platform for studying early embryogenesis and pave the way to creating viable synthetic embryos by using cultured cells.


Asunto(s)
Blastocisto/citología , Linaje de la Célula , Implantación del Embrión , Células Madre Pluripotentes Inducidas/citología , Células Madre Embrionarias de Ratones/citología , Creación de Embriones para Investigación/métodos , Animales , Blastocisto/metabolismo , Diferenciación Celular , Línea Celular , Células Cultivadas , Técnicas de Reprogramación Celular/métodos , Femenino , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Células Madre Embrionarias de Ratones/metabolismo , Transcriptoma
3.
Immunity ; 56(6): 1220-1238.e7, 2023 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-37130522

RESUMEN

Early-life immune development is critical to long-term host health. However, the mechanisms that determine the pace of postnatal immune maturation are not fully resolved. Here, we analyzed mononuclear phagocytes (MNPs) in small intestinal Peyer's patches (PPs), the primary inductive site of intestinal immunity. Conventional type 1 and 2 dendritic cells (cDC1 and cDC2) and RORgt+ antigen-presenting cells (RORgt+ APC) exhibited significant age-dependent changes in subset composition, tissue distribution, and reduced cell maturation, subsequently resulting in a lack in CD4+ T cell priming during the postnatal period. Microbial cues contributed but could not fully explain the discrepancies in MNP maturation. Type I interferon (IFN) accelerated MNP maturation but IFN signaling did not represent the physiological stimulus. Instead, follicle-associated epithelium (FAE) M cell differentiation was required and sufficient to drive postweaning PP MNP maturation. Together, our results highlight the role of FAE M cell differentiation and MNP maturation in postnatal immune development.


Asunto(s)
Células M , Ganglios Linfáticos Agregados , Intestinos , Intestino Delgado , Diferenciación Celular , Mucosa Intestinal
4.
PLoS Pathog ; 19(12): e1011839, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38048363

RESUMEN

The fungal Gß-like protein has been reported to be involved in a variety of biological processes, such as mycelial growth, differentiation, conidiation, stress responses and infection. However, molecular mechanisms of the Gß-like protein in regulating fungal development and pathogenicity are largely unknown. Here, we show that the Gß-like protein gene Bcgbl1 in the gray mold fungus Botrytis cinerea plays a pivotal role in development and pathogenicity by regulating the mitogen-activated protein (MAP) kinases signaling pathways. The Bcgbl1 deletion mutants were defective in mycelial growth, sclerotial formation, conidiation, macroconidial morphogenesis, plant adhesion, and formation of infection cushions and appressorium-like structures, resulting in a complete loss of pathogenicity. Bcgbl1 interacted with BcSte50, the adapter protein of the cascade of MAP kinase (MAPK). Bcgbl1 mutants had reduced phosphorylation levels of two MAPKs, namely Bmp1 and Bmp3, thereby reducing infection. However, deletion of Bcgbl1 did not affect the intracellular cAMP level, and exogenous cAMP could not restore the defects. Moreover, Bcgbl1 mutants exhibited defects in cell wall integrity and oxidative stress tolerance. Transcriptional profiling revealed that Bcgbl1 plays a global role in regulation of gene expression upon hydrophobic surface induction. We further uncovered that three target genes encoding the hydrophobic surface binding proteins (HsbAs) contributed to the adhesion and virulence of B. cinerea. Overall, these findings suggest that Bcgbl1 had multiple functions and provided new insights for deciphering the Bcgbl1-mediated network for regulating development and pathogenicity of B. cinerea.


Asunto(s)
Proteínas Fúngicas , Sistema de Señalización de MAP Quinasas , Virulencia/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Botrytis/genética , Regulación Fúngica de la Expresión Génica , Enfermedades de las Plantas/microbiología , Esporas Fúngicas
5.
Mikrochim Acta ; 191(7): 384, 2024 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-38861028

RESUMEN

Multifunctional N, Fe-doped carbon dots (N, Fe-CDs) were synthesized by the one-step hydrothermal method using ferric ammonium citrate and dicyandiamide as raw materials. The N, Fe-CDs exhibited peroxidase-like (POD) activity by catalyzing the oxidization of 3,3',5,5'-tetramethylbenzidine (TMB) to the green oxidation state ox-TMB in the presence of hydrogen peroxide (H2O2). Subsequently, based on the POD activity of N, Fe-CDs, an efficient and sensitive colorimetric method for the detection of H2O2 and ascorbic acid (AA) was established with a limit of detection of 0.40 µM and 2.05 µM. The proposed detection method has been successfully applied to detect AA in fruit juice, vitamin C tablets, and human serum samples and has exhibited excellent application prospects in biotechnology and food fields. Furthermore, N, Fe-CDs also showed a protective effect on the cell damage caused by H2O2 and could be used as an antioxidant agent.


Asunto(s)
Ácido Ascórbico , Carbono , Jugos de Frutas y Vegetales , Peróxido de Hidrógeno , Oxidación-Reducción , Puntos Cuánticos , Peróxido de Hidrógeno/química , Ácido Ascórbico/química , Humanos , Carbono/química , Puntos Cuánticos/química , Jugos de Frutas y Vegetales/análisis , Bencidinas/química , Colorimetría/métodos , Límite de Detección , Hierro/química , Nitrógeno/química , Peroxidasa/química , Peroxidasa/metabolismo , Antioxidantes/química , Antioxidantes/farmacología
6.
J Environ Manage ; 354: 120205, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38359623

RESUMEN

Formation and extinction of thermal stratifications impact the reservoir ecosystems and have been closely influenced by meteorological and hydrological factors. However, quantifying the relative importance of these crucial environmental factors and mechanisms in reservoir regions characterized by various depths remain comparatively uninvestigated. Tianbao Reservoir is a typical monomictic warm and drinking water source reservoir in Southwest China. This study supplemented field observations with a three-dimensional numerical simulation model to quantitatively analyze mixing and turnover events. Air temperature and wind were two important meteorological factors resulting in hydrodynamics during stratification and mixing processes. Air temperature led to variations in stratification strength and wind-induced fluctuations of thermocline depth. A 10% rise in air temperature increased stratification strength by 18%, and a 3 m/s rise in wind speed induced the deepening of the thermocline by 2.09 m. Two hydrodynamics involved penetrative convection caused by temperature plummets and wind-induced mixing during winter turnover events were identified. Penetrative convection was the main driving force, and wind shear mixed the upper 21% of the mixed layer, which was contributed by convection. Response of water temperature to air temperature in shallow regions was faster (58 d), and the mixing depth caused by the wind was smaller than that in deep regions. Research on physical processes during stratification and mixing processes can provide support for further study on water quality deterioration distributions.


Asunto(s)
Ecosistema , Calidad del Agua , Estaciones del Año , Temperatura , Viento , China , Monitoreo del Ambiente
7.
BMC Cancer ; 23(1): 1257, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38124049

RESUMEN

PURPOSE: To explore the potential role of signal transducer and activator of transcription 5A (STAT5A) in the metastasis of breast cancer, and its mechanism of regulation underlying. METHODS AND RESULTS: TCGA datasets were used to evaluate the expression of STAT5A in normal and different cancerous tissues through TIMER2.0, indicating that STAT5A level was decreased in breast cancer tissues compared with normal ones. Gene Set Enrichment Analysis predicted that STAT5A was associated with the activation of immune cells and cell cycle process. We further demonstrated that the infiltration of immune cells was positively associated with STAT5A level. Influorescence staining revealed the expression and distribution of F-actin was regulated by STAT5A, while colony formation assay, wound healing and transwell assays predicted the inhibitory role of STAT5A in the colony formation, migratory and invasive abilities in breast cancer cells. In addition, overexpression of the Notch3 intracellular domain (N3ICD), the active form of Notch3, resulted in the increased expression of STAT5A. Conversely, silencing of Notch3 expression by siNotch3 decreased STAT5A expression, supporting that STAT5A expression is positively associated with Notch3 in human breast cancer cell lines and breast cancer tissues. Mechanistically, chromatin immunoprecipitation showed that Notch3 was directly bound to the STAT5A promoter and induced the expression of STAT5A. Moreover, overexpressing STAT5A partially reversed the enhanced mobility of breast cancer cells following Notch3 silencing. Low expression of Notch3 and STAT5A predicted poorer prognosis of patients with breast cancer. CONCLUSION: The present study demonstrates that Notch3 inhibits metastasis in breast cancer through inducing transcriptionally STAT5A, which was associated with tumor-infiltrating immune cells, providing a novel strategy to treat breast cancer.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Factor de Transcripción STAT5/genética , Factor de Transcripción STAT5/metabolismo , Transducción de Señal/genética , Inmunoprecipitación de Cromatina , Receptor Notch3/genética , Proteínas Supresoras de Tumor/genética
8.
Nanotechnology ; 34(12)2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36548986

RESUMEN

Recently, carbon dots (CDs) have exhibited promising applications in the fluorescence detection of various ions and biomolecules. In this work, one kind of nitrogen-doped CDs (N-CDs) with high fluorescence intensity was synthesized, characterized by transmission electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy, Fourier-transform infrared, UV-vis absorption spectra, and fluorescence spectra. The results show that the spherical and uniform N-CDs (quantum yield: 60.2%) have remarkable fluorescence properties and photostability, which makes N-CDs can be utilized as an 'on-off-on' sensor for Hg2+and glutathione (GSH). In addition, the pH-sensitive behavior of N-CDs makes it also applicable to H+detection under acid conditions (pKa = 3.53). The linear range of the 'turn-off' sensor detecting Hg2+was 0.014-50µM, with a 0.014µM limit of detection (LOD). GSH was detected by the fluorescence 'turn-on' method with a linear range of 0.125-60µM and a LOD of 0.125µM. The outstanding performance of N-CDs makes it potential applications in ecological pollution and biomolecule visualization monitoring.


Asunto(s)
Mercurio , Puntos Cuánticos , Colorantes Fluorescentes/química , Carbono/química , Puntos Cuánticos/química , Espectrometría de Fluorescencia/métodos , Glutatión , Iones , Nitrógeno/química , Concentración de Iones de Hidrógeno
9.
J Fluoresc ; 33(2): 459-469, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36441340

RESUMEN

Carbon dots (CDs) have excellent fluorescence properties and can be used in many research fields. In this paper, carbon dots were prepared by microwave-assisted pyrolysis of citric acid and urea, characterized by transmission electron microscope (TEM), X-ray diffractometer (XRD), 13C-NMR spectrum, zeta potential, Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible (UV-vis) absorption and fluorescence spectra, and detected the Hg2+ and ascorbic acid (AA) sequentially. It showed that carbon dots were hollow, spherical particles and less than 10 nm, photoluminescence quantum yield of carbon dots was about 15%. The CDs were selective and sensitive to Hg2+ and AA based on the "on-off-on" fluorescence behavior. The detection limits of CDs for Hg2+ and AA were 0.138 µM and 0.212 µM, respectively. Fluorescence response mechanism of CDs was also discussed.


Asunto(s)
Mercurio , Puntos Cuánticos , Ácido Ascórbico , Puntos Cuánticos/química , Carbono/química , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría de Fluorescencia , Colorantes Fluorescentes/química
10.
BMC Bioinformatics ; 23(1): 276, 2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35831796

RESUMEN

BACKGROUND: Single-cell RNA sequencing (scRNA-seq) allows the detection of rare cell types in complex tissues. The detection of markers for rare cell types is useful for further biological analysis of, for example, flow cytometry and imaging data sets for either physical isolation or spatial characterization of these cells. However, only a few computational approaches consider the problem of selecting specific marker genes from scRNA-seq data. RESULTS: Here, we propose sc2marker, which is based on the maximum margin index and a database of proteins with antibodies, to select markers for flow cytometry or imaging. We evaluated the performances of sc2marker and competing methods in ranking known markers in scRNA-seq data of immune and stromal cells. The results showed that sc2marker performed better than the competing methods in accuracy, while having a competitive running time.


Asunto(s)
Análisis de la Célula Individual , Programas Informáticos , Perfilación de la Expresión Génica/métodos , RNA-Seq , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual/métodos , Secuenciación del Exoma
11.
NMR Biomed ; 35(1): e4617, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34562038

RESUMEN

Excessive manganese is neurotoxic, which means that it can affect the concentrations of metabolite in 1 H MRS. In addition, manganese is paramagnetic and it may influence the relaxation times of the metabolite. The aim of this study is to assess the sensitivity of the metabolite relaxation properties and concentrations to exogenous manganese deposition in the globus pallidus (GP) of rat brain after repeated manganese injection. Proton magnetic resonance spectroscopy (1 H MRS) experiments in vivo and ex vivo were carried out to evaluate the changes in the metabolite concentration and the major metabolite relaxation times, and histological experiments were also performed after repeated manganese administration. Only the T1 value for N-acetylaspartate (NAA) of the GP was significantly reduced after 1 day of manganese injection compared with that of the control group (p < 0.025). The T1 and T2 values for NAA and total creatine (tCr) (p < 0.025), along with the amounts of NAA, tCr, myo-inositol, choline, and glutamate (p < 0.0086) in the GP, were all significantly decreased after 5 days of manganese administration compared with that of the control group. The changes in the concentration and relaxation properties of NAA and tCr in the GP of rat brain indicated that manganese represented paramagnetism and neurotoxicity after repeated administration. Accurate knowledge of relaxation properties and concentrations of NAA and tCr in this study could help appropriate selection of sequence parameters to improve the ability to distinguish the brain regions affected in cases of manganese poisoning.


Asunto(s)
Globo Pálido/efectos de los fármacos , Manganeso/toxicidad , Espectroscopía de Protones por Resonancia Magnética/métodos , Animales , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Colina/metabolismo , Creatina/metabolismo , Globo Pálido/metabolismo , Globo Pálido/patología , Ratas , Ratas Sprague-Dawley
12.
J Exp Bot ; 73(11): 3758-3773, 2022 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-35259265

RESUMEN

Ring rot is a destructive apple disease caused by Botryosphaeria dothidea. The resistance mechanism of apple plants to B. dothidea remains unclear. Here, we show that APPLE VACUOLAR PROCESSING ENZYME 4 (MdVPE4) is involved in resistance to B. dothidea. MdVPE4 silencing reduced fruit disease resistance, whereas its overexpression improved resistance. Gene expression analysis revealed that MdVPE4 influenced the expression of fruit disease resistance-related genes, such as APPLE POLYGALACTURONASE 1 (MdPG1), APPLE POLYGALACTURONASE INHIBITOR PROTEIN 1 (MdPGIP1), APPLE ENDOCHITINASE 1 (MdCHI1), and APPLE THAUMATIN-LIKE PROTEIN 1 (MdTHA1). The expression of the four genes responding to B. dothidea infection decreased in MdVPE4-silenced fruits. Further analysis demonstrated that B. dothidea infection induced MdVPE4 expression and enzyme activation in apple fruits. Moreover, MdVPE4 activity was modulated by apple cysteine proteinase inhibitor 1 (MdCPI1), which also contributed to resistance towards B. dothidea, as revealed by gene overexpression and silencing analysis. MdCPI1 interacted with MdVPE4 and inhibited its activity. However, MdCPI1 expression was decreased by B. dothidea infection. Taken together, our findings indicate that the interaction between MdVPE4 and MdCPI1 plays an important role in modulating fruit disease resistance to B. dothidea.


Asunto(s)
Resistencia a la Enfermedad , Malus , Cisteína Endopeptidasas , Inhibidores de Cisteína Proteinasa , Resistencia a la Enfermedad/genética , Frutas/genética , Malus/genética , Enfermedades de las Plantas/genética , Poligalacturonasa
13.
J Fish Biol ; 101(3): 699-710, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35751135

RESUMEN

As serine/threonine protein kinases, mitogen-activated protein kinases (MAPK) take part in cellular metabolism. This work found 14 MAPK genes in the yellow catfish (Pelteobagrus fulviadraco) genome and evaluated their taxonomy, conserved domains and evolutionary linkages for a better understanding of the MAPK gene family's evolutionary relationship and antibacterial immune response. The findings revealed that several MAPK genes are activated in response to immunological and inflammatory responses. Collinearity research revealed that in yellow catfish and zebrafish, there are six pairs of highly similar MAPK genes, indicating that these genes have been more conserved throughout evolution. The MAPK gene quantification findings revealed that JNK1a, JNK1b, p38delta and p38alpha b expression levels were considerably upregulated, indicating that they act in fish innate immunity. The findings implied that MAPK genes may involve in defence against detrimental microbe in yellow catfish, which will help researchers better understand how MAPK genes work in the innate immune system.


Asunto(s)
Bagres , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Aeromonas hydrophila/fisiología , Animales , Bagres/genética , Bagres/metabolismo , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Perfilación de la Expresión Génica , Inmunidad Innata/genética , Proteínas Quinasas Activadas por Mitógenos/genética , Pez Cebra/genética
14.
Nucleic Acids Res ; 47(5): 2306-2321, 2019 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-30605520

RESUMEN

RNA can directly bind to purine-rich DNA via Hoogsteen base pairing, forming a DNA:RNA triple helical structure that anchors the RNA to specific sequences and allows guiding of transcription regulators to distinct genomic loci. To unravel the prevalence of DNA:RNA triplexes in living cells, we have established a fast and cost-effective method that allows genome-wide mapping of DNA:RNA triplex interactions. In contrast to previous approaches applied for the identification of chromatin-associated RNAs, this method uses protein-free nucleic acids isolated from chromatin. High-throughput sequencing and computational analysis of DNA-associated RNA revealed a large set of RNAs which originate from non-coding and coding loci, including super-enhancers and repeat elements. Combined analysis of DNA-associated RNA and RNA-associated DNA identified genomic DNA:RNA triplex structures. The results suggest that triplex formation is a general mechanism of RNA-mediated target-site recognition, which has major impact on biological functions.


Asunto(s)
ADN/química , ADN/aislamiento & purificación , Conformación de Ácido Nucleico , ARN/química , ARN/aislamiento & purificación , Emparejamiento Base , Secuencia de Bases , Sitios de Unión , Cromatina/genética , Cromatina/metabolismo , Mapeo Cromosómico , ADN/genética , Elementos de Facilitación Genéticos/genética , Células HeLa , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Purinas/química , Purinas/metabolismo , ARN/genética , ARN Largo no Codificante/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Reproducibilidad de los Resultados , Factores de Transcripción/metabolismo
15.
BMC Pulm Med ; 21(1): 197, 2021 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-34112136

RESUMEN

BACKGROUND: Hereditary hemorrhagic telangiectasia (HHT) is a disease characterized by arteriovenous malformations in the skin and mucous membranes. We enrolled a large pedigree comprising 32 living members, and screened for mutations responsible for HHT. METHODS: We performed whole-exome sequencing to identify novel mutations in the pedigree after excluding three previously reported HHT-related genes using Sanger sequencing. We then performed in silico functional analysis of candidate mutations that were obtained using a variant filtering strategy to identify mutations responsible for HHT. RESULTS: After screening the HHT-related genes, activin A receptor-like type 1 (ACVRL1), endoglin (ENG), and SMAD family member 4 (SMAD4), we did not detect any co-segregated mutations in this pedigree. Whole-exome sequencing analysis of 7 members and Sanger sequencing analysis of 16 additional members identified a mutation (c.784A > G) in the NSF attachment protein gamma (NAPG) gene that co-segregated with the disease. Functional prediction showed that the mutation was deleterious and might change the conformational stability of the NAPG protein. CONCLUSIONS: NAPG c.784A > G may potentially lead to HHT. These results expand the current understanding of the genetic contributions to HHT pathogenesis.


Asunto(s)
Familia , Proteínas Solubles de Unión al Factor Sensible a la N-Etilmaleimida/genética , Telangiectasia Hemorrágica Hereditaria/genética , China , Femenino , Humanos , Masculino , Mutación , Linaje , Secuenciación del Exoma
16.
Sensors (Basel) ; 21(4)2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33562715

RESUMEN

Sign language is the most important way of communication for hearing-impaired people. Research on sign language recognition can help normal people understand sign language. We reviewed the classic methods of sign language recognition, and the recognition accuracy is not high enough because of redundant information, human finger occlusion, motion blurring, the diversified signing styles of different people, and so on. To overcome these shortcomings, we propose a multi-scale and dual sign language recognition Network (SLR-Net) based on a graph convolutional network (GCN). The original input data was RGB videos. We first extracted the skeleton data from them and then used the skeleton data for sign language recognition. SLR-Net is mainly composed of three sub-modules: multi-scale attention network (MSA), multi-scale spatiotemporal attention network (MSSTA) and attention enhanced temporal convolution network (ATCN). MSA allows the GCN to learn the dependencies between long-distance vertices; MSSTA can directly learn the spatiotemporal features; ATCN allows the GCN network to better learn the long temporal dependencies. The three different attention mechanisms, multi-scale attention mechanism, spatiotemporal attention mechanism, and temporal attention mechanism, are proposed to further improve the robustness and accuracy. Besides, a keyframe extraction algorithm is proposed, which can greatly improve efficiency by sacrificing a little accuracy. Experimental results showed that our method can reach 98.08% accuracy rate in the CSL-500 dataset with a 500-word vocabulary. Even on the challenging dataset DEVISIGN-L with a 2000-word vocabulary, it also reached a 64.57% accuracy rate, outperforming other state-of-the-art sign language recognition methods.


Asunto(s)
Reconocimiento de Normas Patrones Automatizadas , Lengua de Signos , Algoritmos , Humanos , Movimiento (Física) , Vocabulario
17.
Neuroimage ; 210: 116588, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32004718

RESUMEN

An enriched environment (EE) provides multi-dimensional stimuli to the brain. EE exposure for days to months induces functional and structural neuroplasticity. In this study, manganese-enhanced magnetic resonance imaging (MEMRI) was used to map the accumulative whole-brain activities associated with a 7-day EE exposure in freely-moving adult male mice, followed by c-Fos immunochemical assessments. Relative to the mice residing in a standard environment (SE), the mice subjected to EE treatment had significantly enhanced regional MEMRI signal intensities in the prefrontal cortex, somatosensory cortices, basal ganglia, amygdala, motor thalamus, lateral hypothalamus, ventral hippocampus and midbrain dopaminergic areas at the end of the 7-day exposure, likely attributing to enhanced Mn2+ uptake/transport associated with brain activities at both the regional and macroscale network levels. Some of, but not all, the brain regions in the EE-treated mice showing enhanced MEMRI signal intensity had accompanying increases in c-Fos expression. The EE-treated mice were also found to have significantly increased overall amount of food consumption, decreased body weight gain and upregulated tyrosine hydroxylase (TH) expression in the midbrain dopaminergic areas. Taken together, these results demonstrated that the 7-day EE exposure was associated with elevated cumulative activities in the nigrostriatal, mesolimbic and corticostriatal circuits underpinning reward, motivation, cognition, motor control and appetite regulation. Such accumulative activities might have served as the substrate of EE-related neuroplasticity and the beneficial effects of EE treatment on neurological/psychiatric conditions including drug addiction, Parkinson's disease and eating disorder.


Asunto(s)
Conducta Animal/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Cloruros/administración & dosificación , Imagen por Resonancia Magnética/métodos , Compuestos de Manganeso/administración & dosificación , Neuroimagen/métodos , Animales , Encéfalo/metabolismo , Ambiente , Aumento de la Imagen , Masculino , Ratones , Proteínas Proto-Oncogénicas c-fos/metabolismo
18.
Fish Shellfish Immunol ; 86: 608-617, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30502469

RESUMEN

Temperature is an important environmental factor influencing crustacean resistance to pathogen infection. However, the mechanism underlying immune regulation by temperature remains unclear in crustacean. Here, we report a Ras gene of crayfish (designated as PcRAS1) which is involved in immune regulation of crayfish under high temperature. PcRAS1 is induced by both high temperature and bacterial infection and the induction by bacterial infection is associated with temperature. Significant changes of PcRAS1 expression was observed at 32 °C and 24 °C after infection with Aeromonas hydrophila, but relative moderate alternation was found at 16 °C after challenged with A. hydrophila. PcRAS1 silencing significantly reduced crayfish survival from high temperature (32 °C and 24 °C) or bacterial infection at 32 °C, but there was no significant effect on survival from bacterial infection at 24 °C or 16 °C. Further analysis reveals that PO activity is reduced by high temperature or enhanced by bacterial infection. Moreover, both the decreased PO activity and the enhanced PO activity are affected by PcRAS1 expression. PcRAS1 silencing further reduces PO activity under high temperature and compromises the enhanced PO activity by bacterial infection. Lipid peroxidation (LPO) and total antioxidant capacity (TAC) are also involved in the responses to high temperature. LPO is enhanced by lower temperature. TAC is reduced by high temperature and TAC change resulting from high temperature is amplified by PcRAS1 silencing. These results collectively indicate that PcRAS1 is involved in immune regulation against bacterial infection mediated by temperature.


Asunto(s)
Aeromonas hydrophila , Astacoidea/genética , Astacoidea/microbiología , Genes ras , Infecciones por Bacterias Gramnegativas/veterinaria , Respuesta al Choque Térmico , Calor , Animales , Astacoidea/inmunología , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/mortalidad , Peroxidación de Lípido , Masculino , Monofenol Monooxigenasa/genética , Monofenol Monooxigenasa/metabolismo
19.
PLoS Genet ; 12(6): e1006129, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27352031

RESUMEN

Mutations in the human MECP2 gene cause Rett syndrome (RTT), a severe neurodevelopmental disorder that predominantly affects girls. Despite decades of work, the molecular function of MeCP2 is not fully understood. Here we report a systematic identification of MeCP2-interacting proteins in the mouse brain. In addition to transcription regulators, we found that MeCP2 physically interacts with several modulators of RNA splicing, including LEDGF and DHX9. These interactions are disrupted by RTT causing mutations, suggesting that they may play a role in RTT pathogenesis. Consistent with the idea, deep RNA sequencing revealed misregulation of hundreds of splicing events in the cortex of Mecp2 knockout mice. To reveal the functional consequence of altered RNA splicing due to the loss of MeCP2, we focused on the regulation of the splicing of the flip/flop exon of Gria2 and other AMPAR genes. We found a significant splicing shift in the flip/flop exon toward the flop inclusion, leading to a faster decay in the AMPAR gated current and altered synaptic transmission. In summary, our study identified direct physical interaction between MeCP2 and splicing factors, a novel MeCP2 target gene, and established functional connection between a specific RNA splicing change and synaptic phenotypes in RTT mice. These results not only help our understanding of the molecular function of MeCP2, but also reveal potential drug targets for future therapies.


Asunto(s)
Empalme Alternativo/genética , Síndrome de Rett/genética , Animales , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Exones/genética , Femenino , Masculino , Proteína 2 de Unión a Metil-CpG/genética , Ratones , Ratones Noqueados , Mutación/genética , Fenotipo , ARN/genética
20.
J Neurosci ; 37(13): 3671-3685, 2017 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-28270572

RESUMEN

Rett syndrome (RTT) is a debilitating neurodevelopmental disorder caused by mutations in the MECP2 gene. To facilitate the study of cellular mechanisms in human cells, we established several human stem cell lines: human embryonic stem cell (hESC) line carrying the common T158M mutation (MECP2T158M/T158M ), hESC line expressing no MECP2 (MECP2-KO), congenic pair of wild-type and mutant RTT patient-specific induced pluripotent stem cell (iPSC) line carrying the V247fs mutation (V247fs-WT and V247fs-MT), and iPSC line in which the V247fs mutation was corrected by CRISPR/Cas9-based genome editing (V247fs-MT-correction). Detailed analyses of forebrain neurons differentiated from these human stem cell lines revealed genotype-dependent quantitative phenotypes in neurite growth, dendritic complexity, and mitochondrial function. At the molecular level, we found a significant reduction in the level of CREB and phosphorylated CREB in forebrain neurons differentiated from MECP2T158M/T158M , MECP2-KO, and V247fs-MT stem cell lines. Importantly, overexpression of CREB or pharmacological activation of CREB signaling in those forebrain neurons rescued the phenotypes in neurite growth, dendritic complexity, and mitochondrial function. Finally, pharmacological activation of CREB in the female Mecp2 heterozygous mice rescued several behavioral defects. Together, our study establishes a robust in vitro platform for consistent quantitative evaluation of genotype-dependent RTT phenotypes, reveals a previously unappreciated role of CREB signaling in RTT pathogenesis, and identifies a potential therapeutic target for RTT.SIGNIFICANCE STATEMENT Our study establishes a robust human stem cell-based platform for consistent quantitative evaluation of genotype-dependent Rett syndrome (RTT) phenotypes at the cellular level. By providing the first evidence that enhancing cAMP response element binding protein signaling can alleviate RTT phenotypes both in vitro and in vivo, we reveal a previously unappreciated role of cAMP response element binding protein signaling in RTT pathogenesis, and identify a potential therapeutic target for RTT.


Asunto(s)
Proteína de Unión a CREB/metabolismo , Células-Madre Neurales/metabolismo , Células-Madre Neurales/patología , Síndrome de Rett/metabolismo , Síndrome de Rett/patología , Animales , Línea Celular , Progresión de la Enfermedad , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Síndrome de Rett/etiología , Transducción de Señal
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