Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Sci Rep ; 13(1): 13194, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37580328

RESUMO

Embryogenic tissue (ET) is important for genetic modification and plant re-generation. The proliferation ability and vigor of ET are crucial for plant propagation via somatic embryogenesis. In this study, ET was induced from mature zygotic embryos in blue spruce (Picea pungens Engelm.). There were significant differences in ET induction between two provenances, i.e. 78.8 ± 12.5% and 62.50 ± 12.8% respectively. Effects of 2,4-Dichlorophenoxy acetic acid (2,4-D), 6-Benzyl amino-purine (6-BA) and/or sucrose on ET proliferation and somatic embryo (SE) maturation were further investigated with four cell lines. The highest ET proliferation rate reached 1473.7 ± 556.0% biweekly. Concentrations of 2,4-D or 6-BA applied at tissue proliferation stage impacted SE maturation among the cell lines, whereas sucrose showed less effects. The highest rate, 408 ± 230 mature SEs/g FW, was achieved in SE maturation cultures. This research demonstrated that the culture conditions, i.e. the specific concentrations of 2,4-D and BA, at ET proliferation stage affected not only ET growth, but also the quality of ET for SE maturation. This study revealed the necessity and benefit in developing both the general and the genotype-specific protocols for efficient production of mature SEs, or somatic plants in blue spruce.


Assuntos
Picea , Reguladores de Crescimento de Plantas , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Picea/genética , Sacarose/farmacologia , Sacarose/metabolismo , Proliferação de Células , Ácido 2,4-Diclorofenoxiacético/farmacologia , Sementes , Técnicas de Embriogênese Somática de Plantas/métodos
2.
Sci China Life Sci ; 66(6): 1392-1407, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36723795

RESUMO

Programmed DNA double-strand break (DSB) formation is a crucial step in meiotic recombination, yet techniques for high-efficiency and precise mapping of the 3' ends of DSBs are still in their infancy. Here, we report a novel technique, named DNA End tailing and sequencing (DEtail-seq), which can directly and ultra-efficiently characterize the 3' ends of meiotic DSBs with near single-nucleotide resolution in a variety of species, including yeast, mouse, and human. We find that the 3' ends of meiotic DSBs are stable without significant resection in budding yeast. Meiotic DSBs are strongly enriched in de novo H3K4me3 peaks in the mouse genome at leptotene stage. We also profile meiotic DSBs in human and find DSB hotspots are enriched near the common fragile sites during human meiosis, especially at CCCTC-binding factor (CTCF)-associated enhancers. Therefore, DEtail-seq provides a powerful method to detect DSB ends in various species, and our results provide new insights into the distribution and regulation of meiotic DSB hotspots.


Assuntos
Quebras de DNA de Cadeia Dupla , Proteínas de Saccharomyces cerevisiae , Camundongos , Humanos , Animais , Saccharomyces cerevisiae/genética , Recombinação Homóloga , Proteínas de Saccharomyces cerevisiae/genética , Meiose/genética
3.
Sci Rep ; 11(1): 19072, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34561508

RESUMO

This study developed somatic embryogenesis protocols for Picea pungens (Engelm), an important ornamental species, including initiation, proliferation, maturation, germination, and acclimation. Somatic embryogenic tissues were induced from mature zygotic embryos of five families, with a frequency of [Formula: see text] 22% for each. Embryogenic tissues (ET) from 13 clones of three families were proliferated for one week, achieving an average rate of 179.1%. The ET of 38 clones of three families were cultured in maturation medium for six weeks; 188 mature embryos on average were counted per gram ET cultured, of which [Formula: see text] 81.1% appeared normal, and each clone developed at least 28 normally matured embryos. A total of 69.9% or more of cotyledonary somatic embryos germinated normally and developed into normal emblings. The experiment of transplanting the emblings into a greenhouse had an average survival rate of 68.5%. Considerable variation among and within families during initiation and proliferation was observed, but this variation decreased in the maturation and germination. Changing the concentration of plant growth regulator of the initiation medium did not significantly change the initiation frequency. We recommend incorporating these protocols into the current Picea pungens practical programs, although further research is essential to increase efficiencies and reduce cost.


Assuntos
Picea/embriologia , Sementes/crescimento & desenvolvimento , Germinação , Picea/fisiologia
4.
Stem Cell Res Ther ; 12(1): 53, 2021 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-33422149

RESUMO

BACKGROUND: Mesenchymal stromal cell (MSC)-based therapies are being actively investigated in various inflammatory disorders. However, functional variability among MSCs cultured in vitro will lead to distinct therapeutic efficacies. Until now, the mechanisms behind immunomodulatory functional variability in MSCs are still unclear. METHODS: We systemically investigated transcriptomic variations among MSC samples derived from multiple tissues to reveal their effects on immunomodulatory functions of MSCs. We then analyzed transcriptomic changes of MSCs licensed with INFγ to identify potential molecular mechanisms that result in distinct MSC samples with different immunomodulatory potency. RESULTS: MSCs were clustered into distinct groups showing different functional enrichment according to transcriptomic patterns. Differential expression analysis indicated that different groups of MSCs deploy common regulation networks in response to inflammatory stimulation, while expression variation of genes in the networks could lead to different immunosuppressive capability. These different responsive genes also showed high expression variability among unlicensed MSC samples. Finally, a gene panel was derived from these different responsive genes and was able to regroup unlicensed MSCs with different immunosuppressive potencies. CONCLUSION: This study revealed genes with expression variation that contribute to immunomodulatory functional variability of MSCs and provided us a strategy to identify candidate markers for functional variability assessment of MSCs.


Assuntos
Células-Tronco Mesenquimais , Diferenciação Celular , Células Cultivadas , Humanos , Imunomodulação , Transdução de Sinais
5.
Cell Biosci ; 11(1): 24, 2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33485387

RESUMO

BACKGROUND: Human pluripotent stem cell-derived limbal stem cells (hPSC-derived LSCs) provide a promising cell source for corneal transplants and ocular surface reconstruction. Although recent efforts in the identification of LSC markers have increased our understanding of the biology of LSCs, much more remains to be characterized in the developmental origin, cell fate determination, and identity of human LSCs. The lack of knowledge hindered the establishment of efficient differentiation protocols for generating hPSC-derived LSCs and held back their clinical application. RESULTS: Here, we performed a time-course single-cell RNA-seq to investigate transcriptional heterogeneity and expression changes of LSCs derived from human embryonic stem cells (hESCs). Based on current protocol, expression heterogeneity of reported LSC markers were identified in subpopulations of differentiated cells. EMT has been shown to occur during differentiation process, which could possibly result in generation of untargeted cells. Pseudotime trajectory analysis revealed transcriptional changes and signatures of commitment of hESCs-derived LSCs and their progeny-the transit amplifying cells. CONCLUSION: Single-cell RNA-seq revealed time-course expression changes and significant transcriptional heterogeneity during hESC-derived LSC differentiation in vitro. Our results demonstrated candidate developmental trajectory and several new candidate markers for LSCs, which could facilitate elucidating the identity and developmental origin of human LSCs in vivo.

6.
Epigenomics ; 13(2): 99-112, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33406894

RESUMO

Aim: To identify differential mRNA and ncRNA expression profiles and competing endogenous RNA-associated regulatory networks during the progression of atherosclerosis (AS). Materials & methods: We systematically analyzed whole-transcriptome sequencing of samples from different stages of AS to evaluate their long noncoding RNA (lncRNA), circular RNA (circRNA), miRNA and mRNA profiles. Results: We constructed three AS-related competing endogenous RNA regulatory networks of differentially expressed circRNAs, lncRNAs, miRNAs and mRNAs. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that the circRNAs in the network were enriched in lipid metabolic processes and participated in the PPAR signaling pathway. Furthermore, lncRNAs were related to receptor activity, myofibrils and cardiovascular system development. Conclusion: The current findings further clarified the regulatory mechanisms at different stages of AS and may provide new ideas and targets for AS.


Assuntos
Aterosclerose/genética , Redes Reguladoras de Genes/genética , MicroRNAs/genética , RNA Circular/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Transcriptoma/genética , Animais , Aterosclerose/patologia , Biologia Computacional , Ontologia Genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/genética
7.
Stem Cell Res Ther ; 11(1): 149, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32252818

RESUMO

BACKGROUND: Mesenchymal stem/stromal cells (MSCs) are multipotent cells with a promising application potential in regenerative medicine and immunomodulation. However, MSCs cultured in vitro exhibit functional heterogeneity. The underlying molecular mechanisms that define MSC heterogeneity remain unclear. METHODS: We investigated the gene expression profile via single-cell RNA sequencing (scRNA-seq) of human primary Wharton's jelly-derived MSCs (WJMSCs) cultured in vitro from three donors. We also isolated CD142+ and CD142- WJMSCs based on scRNA-seq data and compared their proliferation capacity and "wound healing" potential in vitro. Meanwhile, we analyzed publicly available adipose-derived MSC (ADMSCs) scRNA-seq data and performed transcriptome comparison between WJMSCs and ADMSCs at the single-cell level. RESULTS: GO enrichment analysis of highly variable genes (HVGs) obtained from WJMSCs revealed that these genes are significantly enriched in extracellular region with binding function, involved in developmental process, signal transduction, cell proliferation, etc. Pathway analysis showed that these HVGs are associated with functional characteristics of classic MSCs, such as inflammation mediated by chemokine and cytokine signaling, integrin signaling, and angiogenesis. After regressing out the batch and cell cycle effects, these HVGs were used for dimension reduction and clustering analysis to identify candidate subpopulations. Differentially expressed gene analysis revealed the existence of several distinct subpopulations of MSCs that exhibit diverse functional characteristics related to proliferation, development, and inflammation response. In line with our data, sorted CD142+ and CD142- WJMSCs showed distinct proliferation capacity as well as "wound healing" potential. Although WJMSCs and ADMSCs were derived from different tissues and were displaying different differentiation potencies, their HVGs were largely overlapped and had similar functional enrichment. CONCLUSION: HVGs identified in MSCs are associated with classic MSC function. Regarding therapeutic potential, these genes are associated with functional characteristics, on which the MSC clinical application were theoretically based, such as development and inflammation response. Altogether, these HVGs hold the potential to be used as candidate markers for further potency association studies.


Assuntos
Células-Tronco Mesenquimais , Geleia de Wharton , Diferenciação Celular , Proliferação de Células/genética , Células Cultivadas , Humanos , RNA-Seq , Cordão Umbilical
8.
Arterioscler Thromb Vasc Biol ; 40(6): 1464-1478, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32268789

RESUMO

OBJECTIVE: Despite the current antiatherosclerotic and antithrombotic therapies, the incidence of advanced atherosclerosis-associated clinical events remains high. Whether long noncoding RNAs (lncRNAs) affect the progression of atherosclerosis and whether they are potential targets for the treatment of advanced atherosclerosis are poorly understood. Approach and Results: The progression of atherosclerotic lesions was accompanied by dynamic alterations in lncRNA expression, as revealed by RNA sequencing and quantitative polymerase chain reaction. Among the dynamically changing lncRNAs, we identified a novel lncRNA, lncRNA Associated with the Progression and Intervention of Atherosclerosis (RAPIA), that was highly expressed in advanced atherosclerotic lesions and in macrophages. Inhibition of RAPIA in vivo not only repressed the progression of atherosclerosis but also exerted atheroprotective effects similar to those of atorvastatin on advanced atherosclerotic plaques that had already formed. In vitro assays demonstrated that RAPIA promoted proliferation and reduced apoptosis of macrophages. A molecular sponge interaction between RAPIA and microRNA-183-5p was demonstrated by dual-luciferase reporter and RNA immunoprecipitation assays. Rescue assays indicated that RAPIA functioned at least in part by targeting the microRNA-183-5p/ITGB1 (integrin ß1) pathway in macrophages. In addition, the transcription factor FoxO1 (forkhead box O1) could bind to the RAPIA promoter region and facilitate the expression of RAPIA. CONCLUSIONS: The progression of atherosclerotic lesions was accompanied by dynamic changes in the expression of lncRNAs. Inhibition of the pivotal lncRNA RAPIA may be a novel preventive and therapeutic strategy for advanced atherosclerosis, especially in patients resistant or intolerant to statins.


Assuntos
Aterosclerose/terapia , Expressão Gênica , Macrófagos/metabolismo , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , Animais , Apoptose/efeitos dos fármacos , Aterosclerose/genética , Aterosclerose/prevenção & controle , Atorvastatina/farmacologia , Proliferação de Células/efeitos dos fármacos , Progressão da Doença , Proteína Forkhead Box O1/metabolismo , Humanos , Integrina beta1/metabolismo , Macrófagos/química , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , MicroRNAs/metabolismo , MicroRNAs/farmacologia , Regiões Promotoras Genéticas/fisiologia , Células RAW 264.7 , RNA Longo não Codificante/fisiologia
9.
Biomed Pharmacother ; 125: 109944, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32062386

RESUMO

Cardiac fibrosis is a common pathological condition that contributes to the progression of many cardiac diseases. Circular RNAs (circRNAs) are emerging as new regulators of cardiac fibrosis. However, the expression and function of circRNAs in cardiac fibrosis remain largely unknown. The present study aims to investigate the circRNA expression profile and identify the roles of circRNAs in cardiac fibrosis. Transforming growth factor-ß1 (TGF-ß1) was used to establish an in vitro model of cardiac fibrosis in cardiac fibroblasts. CircRNA sequencing revealed that a total of 283 circRNAs were aberrantly expressed in fibrotic cardiac fibroblasts, with 79 upregulated and 204 downregulated. The expression changes of randomly selected circRNAs were validated by real-time PCR. A circRNA-based competing endogenous RNA network 1755 nodes and 30394 edges was established, and module analysis was conducted using the plug-in MCODE. KEGG pathway enrichment analysis was performed for mRNAs involved in the top three enriched modules. The results showed that these mRNAs were enriched in cardiac fibrosis-related signalling pathways, including the 'TGF-beta signaling pathway', 'MAPK signaling pathway', 'AMPK signaling pathway', and 'PI3K-Akt signaling pathway'. The predicted ceRNAs and bioinformatics analysis revealed the potential role of circRNAs in cardiac fibrosis, which would provide useful information for understanding the mechanism and finding effective prevention and treatment targets for cardiac fibrosis.


Assuntos
Fibroblastos/patologia , RNA Circular/genética , Fator de Crescimento Transformador beta1/metabolismo , Animais , Biologia Computacional , Regulação para Baixo , Fibrose/patologia , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/genética , Regulação para Cima
10.
Bioresour Technol ; 297: 122481, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31796379

RESUMO

The transformation of biomass using steam gasification is a chemical route to facilitate changes in organic or residue supported carbonaceous substances addicted to carbon mono-oxide, hydrogen including carbon-di-oxide, etc. However, to commercialize the method of steam gasification, the hurdles persist during the gasification as well as downstream processing. This article delivers a summary of the different approaches that are described in the previous studies to achieve H2 refinement and adaptation within the gasifier system. These include advanced aspects in the research and development of biomass gasification (alike advancements under the gasification operation). The upshot of diverse operating conditions like steam flow rate, operating temperature, moisture content, gasifier agents, residence time, biomass to air, steam to biomass, equivalence ratio, etc. towards the execution of biomass gasifier. This review accomplishes that the interdependence of several issues must be considered in point to optimise the producer gas.


Assuntos
Hidrogênio , Vapor , Biomassa , Carbono , Temperatura
11.
Nanomaterials (Basel) ; 10(1)2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31861281

RESUMO

Here, we report the synthesis of copper-manganese alloy (CuMnO2) using graphitic carbon nitride (gCN) as a novel support material. The successful formation of CuMnO2-gCN was confirmed through spectroscopic, optical, and other characterization techniques. We have applied this catalyst as the energy storage material in the alkaline media and it has shown good catalytic behavior in supercapacitor applications. The CuMnO2-gCN demonstrates outstanding electrocapacitive performance, having high capacitance (817.85 A·g-1) and well-cycling stability (1000 cycles) when used as a working electrode material for supercapacitor applications. For comparison, we have also used the gCN and Cu2O-gCN for supercapacitor applications. This study proposes a simple path for the extensive construction of self-attaining double metal alloy with control size and uniformity in high-performance energy-storing materials.

12.
Atherosclerosis ; 287: 134-139, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31272069

RESUMO

BACKGROUND AND AIMS: Plaque progression increases the risk of a cardiovascular event. This study aims to determine whether intraplaque neovascularization (NV) associates with a greater risk of plaque progression. METHODS: Baseline and 12-month follow-up IVUS was used in combination with baseline OCT to assess 164 non-culprit plaques in 118 CAD patients. A generalized estimating equation approach with exchangeable correlation structure was used to correct for the dependency of repeated measurements. RESULTS: Patients were divided into two groups according to NV (52 patients with 62 NV plaques, 66 patients with 102 non-NV plaques). Non-culprit plaques in the NV group exhibited a more frequent occurrence of TCFA (p = 0.004), macrophage (p = 0.005), cholesterol crystal (p = 0.012), calcification (p = 0.030), thinner fibrous cap thickness (FCT) [(86.8 ±â€¯55.1) vs. (127.4 ±â€¯70.1) µm, p = 0.015], larger lipid arc [(219.5 ±â€¯66.9) vs. (179.8 ±â€¯61.4), p = 0.002] compared to the non-NV group. A large change in percent atheroma volume (PAV), plaque plus media cross-sectional area (P&M CSA), plaque volume, and plaque burden was observed from baseline to follow-up in the NV group. Changes in P&M CSA, plaque volume, and plaque burden showed significant differences in fibroatheroma with NV. Intraplaque NV could predict a high risk of plaque progression despite statin therapy [OR 6.521 (95% CI 2.457-17.308), p < 0.001]. CONCLUSIONS: NV might attenuate the benefits of statin therapy in plaque progression. This study may provide a new basis for anti-angiogenic strategies to prevent atherosclerotic plaque progression.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/diagnóstico por imagem , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Placa Aterosclerótica/diagnóstico , Tomografia de Coerência Óptica/métodos , Ultrassonografia de Intervenção/métodos , Doença da Artéria Coronariana/tratamento farmacológico , Vasos Coronários/efeitos dos fármacos , Progressão da Doença , Seguimentos , Humanos , Neovascularização Patológica/diagnóstico , Placa Aterosclerótica/tratamento farmacológico , Estudos Retrospectivos
13.
J Cardiovasc Med (Hagerstown) ; 20(8): 518-524, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30889077

RESUMO

AIMS: This study aimed to investigate the progression and vascular shrinkage of vulnerable plaque lesions with a plaque burden at least 70% among patients with coronary artery disease by optical coherence tomography (OCT) and intravascular ultrasound (IVUS). METHODS: Fifty-six OCT-identified vulnerable plaques from 47 patients were included among coronary angiography-identified nonculprit/nontarget lesions. Serial IVUS images were used to assess plaque progression and vascular shrinkage. RESULTS: Thirty-five small vulnerable plaques (plaque burden <70%, group A) and 21 large vulnerable plaques (plaque burden ≥70%, group B) were identified. The IVUS results at baseline show that mean plaque areas (P < 0.001) and the percentage atheroma volume (PAV) (P < 0.0001) were greater and the minimal lumen area (P < 0.0001) was smaller in group B. The absolute and relative changes in the PAV and mean plaque area from baseline to follow-up were not significantly different. However, the lesions exhibited vessel shrinkage [the mean external elastic membrane (EEM) area (P = 0.02) and mean lumen area (P = 0.03) were significantly smaller in group B] from baseline to follow-up. Patients in group B also exhibited clinical events (recurrent angina symptoms) during the follow-up period. Positive correlations were found between changes in the mean plaque area and the mean EEM area in large vulnerable plaques (r = 0.61, P < 0.0001) and between changes in the mean EEM area and the mean lumen area in large vulnerable plaques (r = 0.61, P < 0.0001). CONCLUSION: Vulnerable plaque progression was not different between small and large vulnerable plaques. However, large vulnerable plaque lesions tended to exhibit vascular shrinkage, which is possible a cause of coronary artery lumen loss in patients with large vulnerable plaques.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Placa Aterosclerótica , Tomografia de Coerência Óptica , Ultrassonografia de Intervenção , Angiografia Coronária , Progressão da Doença , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Recidiva , Ruptura Espontânea , Fatores de Tempo
14.
Small ; 15(11): e1804722, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30735296

RESUMO

Herein, well-defined Pd nanoparticles (NPs) developed on Ni substrate (Pd NPs/Ni) are synthesized via a facile galvanic replacement reaction (GRR) route performed in ethaline-based deep eutectic solvent (DES). For comparison, a Pd NPs/Ni composite is also prepared by the GRR method conducted in an aqueous solution. The Pd NPs/Ni obtained from the ethaline-DES is catalytically more active and durable for the methanol electro-oxidation reaction (MOR) than those of the counterpart derived from conventional aqueous solution and commercial Pd/C under alkaline media. Detailed kinetic analysis indicates that the unique solvent environment offered by ethaline plays vital roles in adjusting the reactivity of the active species and their mass transport properties to control over the genesis of the Pd NPs/Ni nanocomposite. The resulting Pd NPs/Ni catalyst possesses a homogeneous dispersion of Pd NPs with a strong Pd (metal)-Ni (support) interaction. This structure enhances the charge transfer between the support and the active phases, and optimizes the adsorption energy of OH- and CO on the surface, leading to superior electrocatalytic performance. This work provides a novel GRR strategy performed in ethaline-DES to the rational design and construction of advanced metal/support catalysts with strong interaction for improving the activity and durability for MOR.

15.
J Am Heart Assoc ; 7(5)2018 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-29502100

RESUMO

BACKGROUND: Obesity is causally associated with atherosclerosis, and adipose tissue (AT)-derived exosomes may be implicated in the metabolic complications of obesity. However, the precise role of AT-exosomes in atherogenesis remains unclear. We herein aimed to assess the effect of AT-exosomes on macrophage foam cell formation and polarization and subsequent atherosclerosis development. METHODS AND RESULTS: Four types of exosomes isolated from the supernatants of ex vivo subcutaneous AT and visceral AT (VAT) explants that were derived from wild-type mice and high-fat diet (HFD)-induced obese mice were effectively taken up by RAW264.7 macrophages. Both treatment with wild-type VAT exosomes and HFD-VAT exosomes, but not subcutaneous AT exosomes, markedly facilitated macrophage foam cell generation through the downregulation of ATP-binding cassette transporter (ABCA1 and ABCG1)-mediated cholesterol efflux. Decreased expression of liver X receptor-α was also observed. Among the 4 types of exosomes, only HFD-VAT exosomes significantly induced M1 phenotype transition and proinflammatory cytokine (tumor necrosis factor α and interleukin 6) secretion in RAW264.7 macrophages, which was accompanied by increased phosphorylation of NF-κB-p65 but not the cellular expression of NF-κB-p65 or IκB-α. Furthermore, systematic intravenous injection of HFD-VAT exosomes profoundly exacerbated atherosclerosis in hyperlipidemic apolipoprotein E-deficient mice, as indicated by the M1 marker (CD16/32 and inducible nitric oxide synthase)-positive areas and the Oil Red O/Sudan IV-stained area, without affecting the plasma lipid profile and body weight. CONCLUSIONS: This study demonstrated a proatherosclerotic role for HFD-VAT exosomes, which is exerted by regulating macrophage foam cell formation and polarization, indicating a novel link between AT and atherosclerosis in the context of obesity.


Assuntos
Doenças da Aorta/patologia , Aterosclerose/patologia , Exossomos/transplante , Células Espumosas/patologia , Gordura Intra-Abdominal/transplante , Obesidade/patologia , Placa Aterosclerótica , Gordura Subcutânea/transplante , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Doenças da Aorta/genética , Doenças da Aorta/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo , Colesterol/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Progressão da Doença , Exossomos/metabolismo , Exossomos/patologia , Células Espumosas/metabolismo , Gordura Intra-Abdominal/metabolismo , Gordura Intra-Abdominal/patologia , Receptores X do Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Obesidade/metabolismo , Fenótipo , Fosforilação , Células RAW 264.7 , Gordura Subcutânea/metabolismo , Gordura Subcutânea/patologia , Fatores de Tempo , Fator de Transcrição RelA/metabolismo
16.
PLoS One ; 13(2): e0192625, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29444173

RESUMO

Human embryonic stem cells (hESCs) have the potential to form any cell type in the body, making them attractive cell sources in drug screening, regenerative medicine, disease and developmental processes modeling. However, not all hESC lines have the equal potency to generate desired cell types in vitro. Significant variations have been observed for the differentiation efficiency of various human ESC lines. The precise underpinning molecular mechanisms are still unclear. In this work, we compared transcriptome variations of four hESC lines H7, HUES1, HUES8 and HUES9. We found that hESC lines have different gene expression profiles, and these differentially expressed genes (DEGs) are significantly enriched in developmental processes, such as ectodermal, mesodermal and endodermal development. The enrichment difference between hESC lines was consistent with its lineage bias. Among these DEGs, some pluripotency factors and genes involved in signaling transduction showed great variations as well. The pleiotropic functions of these genes in controlling hESC identity and early lineage specification, implicated that different hESC lines may utilize distinct balance mechanisms to maintain pluripotent state. When the balance is broken in a certain environment, gene expression variation between them could impact on their different lineage specification behavior.


Assuntos
Diferenciação Celular , Células-Tronco Embrionárias/metabolismo , Transcriptoma , Células Cultivadas , Células-Tronco Embrionárias/citologia , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/metabolismo
17.
Yi Chuan ; 38(12): 1056-1068, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-28034838

RESUMO

Super-enhancers (SEs) are large clusters of transcriptional enhancers that drive expression of genes controlling cell identity. They play important roles in development, disease initiation and progression such as tumorigenesis. Compared to typical enhancers (TEs), most key oncogenes in tumor cells are driven by SEs, and common diseases such as Alzheimer's disease related variations are enriched in SEs. SEs hold great promising in key oncogenes identification and diseases-associated variants discovery. In this review, we first summarize how to identify enhancers on a genome-wide scale, and then introduce the concept of SEs and the methodology for SEs identification. Lastly, we describe SEs' main structural and functional properties and discuss its application in the future research.


Assuntos
Sequências Reguladoras de Ácido Nucleico/fisiologia , Transcrição Gênica/genética , Animais , Humanos , Sequências Reguladoras de Ácido Nucleico/genética
18.
Adv Exp Med Biol ; 951: 31-45, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27837552

RESUMO

Stem cells are highly promising resources for application in cell therapy, regenerative medicine, drug discovery, toxicology and developmental biology research. Stem cell banks have been increasingly established all over the world in order to preserve their cellular characteristics, prevent contamination and deterioration, and facilitate their effective use in basic and translational research, as well as current and future clinical application. Standardization and quality control during banking procedures are essential to allow researchers from different labs to compare their results and to develop safe and effective new therapies. Furthermore, many stem cells come from once-in-a-life time tissues. Cord blood for example, thrown away in the past, can be used to treat many diseases such as blood cancers nowadays. Meanwhile, these cells stored and often banked for long periods can be immediately available for treatment when needed and early treatment can minimize disease progression. This paper provides an overview of the fundamental principles of stem cell banking, including: (i) a general introduction of the construction and architecture commonly used for stem cell banks; (ii) a detailed section on current quality management practices; (iii) a summary of questions we should consider for long-term storage, such as how long stem cells can be stored stably, how to prevent contamination during long term storage, etc.; (iv) the prospects for stem cell banking.


Assuntos
Bancos de Espécimes Biológicos/normas , Criopreservação/métodos , Sangue Fetal/citologia , Células-Tronco/citologia , Sobrevivência Celular , Seleção do Doador/organização & administração , Sangue Fetal/fisiologia , Humanos , Controle de Qualidade , Células-Tronco/fisiologia
19.
Exp Diabetes Res ; 2012: 128694, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22899900

RESUMO

The skin, the body's largest organ, plays an important role in the biotransformation/detoxification and elimination of xenobiotics and endogenous toxic substances, but its role in oxidative stress and insulin resistance is unclear. We investigated the relationship between skin detoxification and oxidative stress/insulin resistance by examining burn-induced changes in nicotinamide degradation. Rats were divided into four groups: sham-operated, sham-nicotinamide, burn, and burn-nicotinamide. Rats received an intraperitoneal glucose injection (2 g/kg) with (sham-nicotinamide and burn-nicotinamide groups) or without (sham-operated and burn groups) coadministration of nicotinamide (100 mg/kg). The results showed that the mRNA of all detoxification-related enzymes tested was detected in sham-operated skin but not in burned skin. The clearance of nicotinamide and N(1)-methylnicotinamide in burned rats was significantly decreased compared with that in sham-operated rats. After glucose loading, burn group showed significantly higher plasma insulin levels with a lower muscle glycogen level than that of sham-operated and sham-nicotinamide groups, although there were no significant differences in blood glucose levels over time between groups. More profound changes in plasma H(2)O(2) and insulin levels were observed in burn-nicotinamide group. It may be concluded that decreased skin detoxification may increase the risk for oxidative stress and insulin resistance.


Assuntos
Queimaduras/metabolismo , Resistência à Insulina , Estresse Oxidativo , Pele/metabolismo , Animais , Antioxidantes/química , Glicemia/metabolismo , Glicogênio/química , Peróxido de Hidrogênio/química , Insulina/metabolismo , Masculino , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Ratos , Ratos Sprague-Dawley , Xenobióticos/química
20.
Theor Appl Genet ; 123(6): 943-58, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21735236

RESUMO

Changes in water potential, growth elongation, photosynthesis of three-leaf-old seedlings of maize inbred line YQ7-96 under water deficit (WD) for 0.5, 1 and 2 h and re-watering (RW) for 24 h were characterized. Gene expression was analyzed using cDNA microarray covering 11,855 maize unigenes. As for whole maize plant, the expression of WD-regulated genes was characterized by up-regulation. The expression of WD-regulated genes was categorized into eight different patterns, respectively, in leaves and roots. Newly found and WD-affected cellular processes were metabolic process, amino acid and derivative metabolic process and cell death. A great number of the analyzed genes were found to be regulated specifically by RW and commonly by both WD and RW, respectively, in leaves. It is therefore concluded that (1) whole maize plant tolerance to WD, as well as growth recovery from WD, depends at least in part on transcriptional coordination between leaves and roots; (2) WD exerts effects on the maize, especially on basal metabolism; (3) WD could probably affect CO(2) uptake and partitioning, and transport of fixed carbons; (4) WD could likely influence nuclear activity and genome stability; and (5) maize growth recovery from WD is likely involved in some specific signaling pathways related to RW-specific responsive genes.


Assuntos
Secas , Genes de Plantas , Água , Zea mays/crescimento & desenvolvimento , Zea mays/genética , Dióxido de Carbono/metabolismo , Elementos de DNA Transponíveis , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Família Multigênica , Análise de Sequência com Séries de Oligonucleotídeos , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/genética , Plântula/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Estresse Fisiológico , Zea mays/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...