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1.
J Membr Biol ; 257(1-2): 131-142, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38206377

RESUMO

Understanding the interaction between ligands and membrane proteins is important for drug design and optimization. Although investigation using live cells is desirable, it is not feasible in some circumstances and cell fixation is performed to reduce cell motion and degradation. This study compared the effects of five fixatives, i.e., formaldehyde vapor (FV), paraformaldehyde (PFA), acetone, methanol, and ethanol, on kinetic measurements via the LigandTracer method. We found that all five fixatives exerted insignificant effects on lectin-glycan interaction. However, antibody-receptor interaction is markedly perturbed by coagulant fixatives. The acetone fixation changed the binding of the anti-human epidermal growth factor receptor 2 (HER2) antibody to HER2 on the cell membrane from a 1:2 to a 1:1 binding model, while methanol and ethanol abolished the antibody binding possibly by removal of the HER2 receptors on the cell membrane. The capability of binding was retained when methanol fixation was performed at lower temperatures, albeit with a binding model of 1:1 instead. Moreover, whereas cell morphology does not exert a substantial impact on lectin-glycan interaction, it can indeed modify the binding model of antibody-receptor interaction. Our results provided insights into the selection of fixatives for cell-based kinetic studies.


Assuntos
Acetona , Metanol , Fixadores/farmacologia , Cinética , Membrana Celular , Etanol/farmacologia , Lectinas , Polissacarídeos
2.
J Med Virol ; 95(2): e28574, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36772841

RESUMO

Human cytomegalovirus (HCMV) preferentially targets neural progenitor cells (NPCs) in congenitally infected fetal brains, inducing neurodevelopmental disorders. While HCMV expresses several microRNAs (miRNAs) during infection, their roles in NPC infection are unclear. Here, we characterized expression of cellular and viral miRNAs in HCMV-infected NPCs during early infection by microarray and identified seven differentially expressed cellular miRNAs and six significantly upregulated HCMV miRNAs. Deep learning approaches were used to identify potential targets of significantly upregulated HCMV miRNAs against differentially expressed cellular messenger RNA (mRNAs), and the associations with miRNA-mRNA expression changes were observed. Gene ontology enrichment analysis indicated cellular gene targets were significantly enriched in pathways involved in neurodevelopment and cell-cycle processes. Viral modulation of selected miRNAs and cellular gene targets involved in neurodevelopmental processes were further validated by real-time quantitative reverse transcription polymerase chain reaction. Finally, a predicted 3' untranslated region target site of hcmv-miR-US25-1 in Jag1, a factor important for neurogenesis, was confirmed by mutagenesis. Reduction of Jag1 RNA and protein levels in NPCs was observed in response to transient expression of hcmv-miR-US25-1. A hcmv-miR-US25-1 mutant virus (ΔmiR-US25) displayed limited ability to downregulate Jag1 mRNA levels and protein levels during the early infection stage compared with the wild type virus. Our collective experimental and computational investigation of miRNAs and cellular mRNAs expression in HCMV-infected NPCs yields new insights into the roles of viral miRNAs in regulating NPC fate and their contributions to HCMV neuropathogenesis.


Assuntos
Infecções por Citomegalovirus , MicroRNAs , Humanos , MicroRNAs/genética , Citomegalovirus/genética , Células-Tronco/metabolismo
3.
Plant J ; 90(5): 918-928, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28244225

RESUMO

The coordination of shoots and roots is critical for plants to adapt to changing environments by fine-tuning energy production in leaves and the availability of water and nutrients from roots. To understand the genetic architecture of how these two organs covary during developmental ontogeny, we conducted a mapping experiment using Euphrates poplar (Populus euphratica), a so-called hero tree able to grow in the desert. We geminated intraspecific F1 seeds of Euphrates Poplar individually in a tube to obtain a total of 370 seedlings, whose shoot and taproot lengths were measured repeatedly during the early stage of growth. By fitting a growth equation, we estimated asymptotic growth, relative growth rate, the timing of inflection point and duration of linear growth for both shoot and taproot growth. Treating these heterochronic parameters as phenotypes, a univariate mapping model detected 19 heterochronic quantitative trait loci (hQTLs), of which 15 mediate the forms of shoot growth and four mediate taproot growth. A bivariate mapping model identified 11 pleiotropic hQTLs that determine the covariation of shoot and taproot growth. Most QTLs detected reside within the region of candidate genes with various functions, thus confirming their roles in the biochemical processes underlying plant growth.


Assuntos
Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/genética , Populus/crescimento & desenvolvimento , Populus/genética , Plântula/crescimento & desenvolvimento , Plântula/genética , Locos de Características Quantitativas/genética
4.
Cell Physiol Biochem ; 50(1): 332-341, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30282065

RESUMO

BACKGROUND/AIMS: Long non-coding RNAs (lncRNAs) act as competing endogenous RNAs (ceRNAs) to compete for microRNAs (miRNAs) in cancer metastasis. Head and neck squamous cell carcinoma (HNSCC) is one of the most common human cancers and rare biomarkers could predict the clinical prognosis of this disease and its therapeutic effect. METHODS: Weighted gene co-expression network analysis (WGCNA) was performed to identify differentially expressed mRNAs (DEmRNAs) that might be key genes. GO enrichment and protein-protein interaction (PPI) analyses were performed to identify the principal functions of the DEmRNAs. An lncRNA-miRNA-mRNA network was constructed to understand the regulatory mechanisms in HNSCC. The prognostic signatures of mRNAs, miRNAs, and lncRNAs were determined by Gene Expression Profiling Interactive Analysis (GEPIA) and using Kaplan-Meier survival curves for patients with lung squamous cell carcinoma. RESULTS: We identified 2,023 DEmRNAs, 1,048 differentially expressed lncRNAs (DElncRNAs), and 82 differentially expressed miRNAs (DEmiRNAs). We found that eight DEmRNAs, 53 DElncRNAs, and 16 DEmiRNAs interacted in the ceRNA network. Three ceRNAs (HCG22, LINC00460 and STC2) were significantly correlated with survival. STC2 transcript levels were significantly higher in tumour tissues than in normal tissues, and the STC2 expression was slightly upregulated at different stages of HNSCC. CONCLUSION: LINC00460, HCG22 and STC2 exhibited aberrant levels of expression and may participate in the pathogenesis of HNSCC.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidade , Redes Reguladoras de Genes/genética , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Estimativa de Kaplan-Meier , Mapas de Interação de Proteínas/genética , Análise de Sequência de RNA , Carcinoma de Células Escamosas de Cabeça e Pescoço , Transcriptoma
5.
J Virol ; 89(13): 6792-804, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25903338

RESUMO

UNLABELLED: Human cytomegalovirus (HCMV) infection of the developing fetus frequently results in major neural developmental damage. In previous studies, HCMV was shown to downregulate neural progenitor/stem cell (NPC) markers and induce abnormal differentiation. As Notch signaling plays a vital role in the maintenance of stem cell status and is a switch that governs NPC differentiation, the effect of HCMV infection on the Notch signaling pathway in NPCs was investigated. HCMV downregulated mRNA levels of Notch1 and its ligand, Jag1, and reduced protein levels and altered the intracellular localization of Jag1 and the intracellular effector form of Notch1, NICD1. These effects required HCMV gene expression and appeared to be mediated through enhanced proteasomal degradation. Transient expression of the viral tegument proteins of pp71 and UL26 reduced NICD1 and Jag1 protein levels endogenously and exogenously. Given the critical role of Notch signaling in NPC growth and differentiation, these findings reveal important mechanisms by which HCMV disturbs neural cell development in vitro. Similar events in vivo may be associated with HCMV-mediated neuropathogenesis during congenital infection in the fetal brain. IMPORTANCE: Congenital human cytomegalovirus (HCMV) infection is the leading cause of birth defects that primarily manifest as neurological disabilities. Neural progenitor cells (NPCs), key players in fetal brain development, are the most susceptible cell type for HCMV infection in the fetal brain. Studies have shown that NPCs are fully permissive for HCMV infection, which causes neural cell loss and premature differentiation, thereby perturbing NPC fate. Elucidation of virus-host interactions that govern NPC proliferation and differentiation is critical to understanding neuropathogenesis. The Notch signaling pathway is critical for maintaining stem cell status and functions as a switch for differentiation of NPCs. Our investigation into the impact of HCMV infection on this pathway revealed that HCMV dysregulates Notch signaling by altering expression of the Notch ligand Jag1, Notch1, and its active effector in NPCs. These results suggest a mechanism for the neuropathogenesis induced by HCMV infection that includes altered NPC differentiation and proliferation.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Infecções por Citomegalovirus/patologia , Interações Hospedeiro-Patógeno , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas de Membrana/metabolismo , Células-Tronco Neurais/fisiologia , Receptor Notch1/metabolismo , Proteínas da Matriz Viral/metabolismo , Proteínas Virais/metabolismo , Infecções por Citomegalovirus/virologia , Regulação da Expressão Gênica , Humanos , Proteína Jagged-1 , Células-Tronco Neurais/virologia , Estabilidade Proteica , Proteólise , Proteínas Serrate-Jagged
6.
J Virol ; 89(2): 1070-82, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25378484

RESUMO

UNLABELLED: Congenital human cytomegalovirus (HCMV) infection is a leading cause of birth defects, primarily manifesting as neurological disorders. HCMV infection alters expression of cellular microRNAs (miRs) and induces cell cycle arrest, which in turn modifies the cellular environment to favor virus replication. Previous observations found that HCMV infection reduces miR-21 expression in neural progenitor/stem cells (NPCs). Here, we show that infection of NPCs and U-251MG cells represses miR-21 while increasing the levels of Cdc25a, a cell cycle regulator and known target of miR-21. These opposing responses to infection prompted an investigation of the relationship between miR-21, Cdc25a, and viral replication. Overexpression of miR-21 in NPCs and U-251MG cells inhibited viral gene expression, genome replication, and production of infectious progeny, while shRNA-knockdown of miR-21 in U-251MG cells increased viral gene expression. In contrast, overexpression of Cdc25a in U-251MG cells increased viral gene expression and production of infectious progeny and overcame the inhibitory effects of miR-21 overexpression. Three viral gene products-IE1, pp71, and UL26-were shown to inhibit miR-21 expression at the transcriptional level. These results suggest that Cdc25a promotes HCMV replication and elevation of Cdc25a levels after HCMV infection are due in part to HCMV-mediated repression of miR-21. Thus, miR-21 is an intrinsic antiviral factor that is modulated by HCMV infection. This suggests a role for miR-21 downregulation in the neuropathogenesis of HCMV infection of the developing CNS. IMPORTANCE: Human cytomegalovirus (HCMV) is a ubiquitous pathogen and has very high prevalence among population, especially in China, and congenital HCMV infection is a major cause for birth defects. Elucidating virus-host interactions that govern HCMV replication in neuronal cells is critical to understanding the neuropathogenesis of birth defects resulting from congenital infection. In this study, we confirm that HCMV infection downregulates miR-21 but upregulates Cdc25a. Further determined the negative effects of cellular miRNA miR-21 on HCMV replication in neural progenitor/stem cells and U-251MG glioblastoma/astrocytoma cells. More importantly, our results provide the first evidence that miR-21 negatively regulates HCMV replication by targeting Cdc25a, a vital cell cycle regulator. We further found that viral gene products of IE1, pp71, and UL26 play roles in inhibiting miR-21 expression, which in turn causes increases in Cdc25a and benefits HCMV replication. Thus, miR-21 appears to be an intrinsic antiviral factor that represents a potential target for therapeutic intervention.


Assuntos
Citomegalovirus/imunologia , Interações Hospedeiro-Patógeno , MicroRNAs/metabolismo , Células-Tronco Neurais/imunologia , Células-Tronco Neurais/virologia , Replicação Viral , Fosfatases cdc25/metabolismo , Células Cultivadas , Citomegalovirus/fisiologia , Humanos
7.
J Virol ; 87(20): 10968-79, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23903847

RESUMO

Congenital human cytomegalovirus (HCMV) infection is the most frequent infectious cause of birth defects, primarily neurological disorders. Neural progenitor/stem cells (NPCs) are the major cell type in the subventricular zone and are susceptible to HCMV infection. In culture, the differentiation status of NPCs may change with passage, which in turn may alter susceptibility to virus infection. Previously, only early-passage (i.e., prior to passage 9) NPCs were studied and shown to be permissive to HCMV infection. In this study, NPC cultures derived at different gestational ages were evaluated after short (passages 3 to 6) and extended (passages 11 to 20) in vitro passages for biological and virological parameters (i.e., cell morphology, expression of NPC markers and HCMV receptors, viral entry efficiency, viral gene expression, virus-induced cytopathic effect, and release of infectious progeny). These parameters were not significantly influenced by the gestational age of the source tissues. However, extended-passage cultures showed evidence of initiation of differentiation, increased viral entry, and more efficient production of infectious progeny. These results confirm that NPCs are fully permissive for HCMV infection and that extended-passage NPCs initiate differentiation and are more permissive for HCMV infection. Later-passage NPCs being differentiated and more permissive for HCMV infection suggest that HCMV infection in fetal brain may cause more neural cell loss and give rise to severe neurological disabilities with advancing brain development.


Assuntos
Encéfalo/citologia , Citomegalovirus/crescimento & desenvolvimento , Células-Tronco Neurais/fisiologia , Células-Tronco Neurais/virologia , Diferenciação Celular , Humanos , Inoculações Seriadas
9.
Front Plant Sci ; 12: 692494, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335660

RESUMO

Heterophylly, or leaf morphological changes along plant shoot axes, is an important indicator of plant eco-adaptation to heterogeneous microenvironments. Despite extensive studies on the genetic control of leaf shape, the genetic architecture of heterophylly remains elusive. To identify genes related to heterophylly and their associations with plant saline tolerance, we conducted a leaf shape mapping experiment using leaves from a natural population of Populus euphratica. We included 106 genotypes grown under salt stress and salt-free (control) conditions using clonal seedling replicates. We developed a shape tracking method to monitor and analyze the leaf shape using principal component (PC) analysis. PC1 explained 42.18% of the shape variation, indicating that shape variation is mainly determined by the leaf length. Using leaf length along shoot axes as a dynamic trait, we implemented a functional mapping-assisted genome-wide association study (GWAS) for heterophylly. We identified 171 and 134 significant quantitative trait loci (QTLs) in control and stressed plants, respectively, which were annotated as candidate genes for stress resistance, auxin, shape, and disease resistance. Functions of the stress resistance genes ABSCISIC ACIS-INSENSITIVE 5-like (ABI5), WRKY72, and MAPK3 were found to be related to many tolerance responses. The detection of AUXIN RESPONSE FACTOR17-LIKE (ARF17) suggests a balance between auxin-regulated leaf growth and stress resistance within the genome, which led to the development of heterophylly via evolution. Differentially expressed genes between control and stressed plants included several factors with similar functions affecting stress-mediated heterophylly, such as the stress-related genes ABC transporter C family member 2 (ABCC2) and ABC transporter F family member (ABCF), and the stomata-regulating and reactive oxygen species (ROS) signaling gene RESPIRATORY BURST OXIDASE HOMOLOG (RBOH). A comparison of the genetic architecture of control and salt-stressed plants revealed a potential link between heterophylly and saline tolerance in P. euphratica, which will provide new avenues for research on saline resistance-related genetic mechanisms.

10.
ACS Chem Neurosci ; 12(5): 872-882, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33571414

RESUMO

Ginnalin A (GA), a polyphenol from the red maple, was reported to be a potential ROS scavenger or an activator of nuclear factor erythroid-2 related factor 2 (Nrf2) in cancer cells. However, whether GA could activate Nrf2 in neuronal cells and the exact mode of action are unknown. We performed molecular docking calculations, which revealed that GA fits well into the five subpockets of the Kelch-like ECH-associated protein1 (Keap1) Kelch domain via hydrogen bonding and hydrophobic interaction. Our cytotoxicity assays demonstrate that pretreating SH-SY5Y cells with 20 µM GA effectively prevents cells from oxidative assault by 6-hydroxydopamine (6-OHDA). Fluorescence imaging indicates that upon the GA pretreatment, Nrf2 dissociates from the Keap1-Nrf2 complex and translocates into nucleus to activate the cellular antixodant system. Real-time qPCR quantification and Western blotting verified that the GA pretreatment elevates NAD(P)H quinone oxidoreductase-1 (NQO1) by more than 4.6-fold, heme oxygenase (HO-1) by about 1.2-fold, and the glutamate-cysteine ligase catalytic (GCLC) subunit by 0.7-fold. The higher antixidant protein levels, along with increased glutathione concentration, decrease intracellular reactive oxygen species and alleviate the 6-OHDA-induced oxidative damage. Silence of Nrf2 abrogates the cytoprotection of the GA pretreatment, confirming that the Keap1/Nrf2-ARE (antioxidant response element) pathway is solely responsible for the GA's biological effects. GA is a promising natural compound for sensitizing neuronal cells' antioxidative defense system to offset oxidative stress, a condition closely linked to the pathogenesis of Parkinson's disease.


Assuntos
Antioxidantes , Desoxiglucose , Ácido Gálico , Fator 2 Relacionado a NF-E2 , Antioxidantes/metabolismo , Linhagem Celular , Desoxiglucose/análogos & derivados , Ácido Gálico/análogos & derivados , Humanos , Repetição Kelch , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Transdução de Sinais
11.
Cell Rep ; 35(6): 109114, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33979624

RESUMO

How genes interact with the environment to shape phenotypic variation and evolution is a fundamental question intriguing to biologists from various fields. Existing linear models built on single genes are inadequate to reveal the complexity of genotype-environment (G-E) interactions. Here, we develop a conceptual model for mechanistically dissecting G-E interplay by integrating previously disconnected theories and methods. Under this integration, evolutionary game theory, developmental modularity theory, and a variable selection method allow us to reconstruct environment-induced, maximally informative, sparse, and casual multilayer genetic networks. We design and conduct two mapping experiments by using a desert-adapted tree species to validate the biological application of the model proposed. The model identifies previously uncharacterized molecular mechanisms that mediate trees' response to saline stress. Our model provides a tool to comprehend the genetic architecture of trait variation and evolution and trace the information flow of each gene toward phenotypes within omnigenic networks.


Assuntos
Redes Reguladoras de Genes/genética , Interação Gene-Ambiente , Humanos
12.
ACS Chem Neurosci ; 11(4): 638-647, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-31967782

RESUMO

Aggregation of misfolded amyloid beta (Aß) peptides into neurotoxic oligomers and fibrils has been implicated as a key event in the etiopathogenesis of Alzheimer's disease (AD). Ginnalin A (GA), a polyphenolic compound isolated from the red maple (Acer rubrum), has been found to possess anticancer, antiglycation, and antioxidation properties. Using thioflavin T (ThT) fluorescence, surface plasmon resonance (SPR), and atomic force microscopy (AFM), we demonstrate that GA can also effectively inhibit Aß aggregation by primarily binding to Aß monomers in a dose-dependent manner. Furthermore, GA can bind to multiple sites of Aß aggregates to disassemble preformed fibrils and convert them into small aggregates. Circular dichroism (CD) spectra showed that these small aggregates are much less abundant in ß-sheets, while cell viability assay confirms that they are essentially innocuous. Molecular dynamics (MD) simulations revealed that GA preferentially contacts with the C- and N-terminal ß-sheets and the U-turn region of Aß(1-42) oligomers through hydrophobic interactions and hydrogen bonding. Compared with other natural compounds that have shown promise in anti-Aß fibrillogenesis and ameliorating Aß-induced cytotoxicity, GA is unique in that it exhibits a more efficient inhibition of Aß aggregation at the very early stage through its strong interaction with Aß monomers and exerts its inhibitory effect at a lower dosage.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Amiloide/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Desoxiglucose/análogos & derivados , Ácido Gálico/análogos & derivados , Fragmentos de Peptídeos/metabolismo , Doença de Alzheimer/metabolismo , Amiloide/efeitos dos fármacos , Peptídeos beta-Amiloides/efeitos dos fármacos , Dicroísmo Circular/métodos , Desoxiglucose/farmacologia , Ácido Gálico/farmacologia , Humanos , Fragmentos de Peptídeos/efeitos dos fármacos , Ressonância de Plasmônio de Superfície/métodos
13.
J Genet ; 982019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30945670

RESUMO

Cupressus gigantea and C. torulosa are ecologically and economically important endemic species of the conifer family Cupressaceae on the Qinghai-Tibetan plateau. C. gigantea was previously classified as a subspecies of C. torulosa because of their similar morphological characteristics and close distribution. In this study, 401 individuals were sampled from 16 populations of the two Cupressus species. The specimens were genotyped using 10 polymorphic microsatellite loci through fluorescence polymerase chain reaction (PCR). The genetic diversity of C. gigantea and C. torulosa populations was generally low, with the highest genetic diversity detected in the population LLS of C. gigantea. Distance-based phylogenetic and principal co-ordinates analyses indicated a clear genetic structures for the 16 populations of the two Cupressus species. Moreover, Mantel test results showed indistinctive correlations between population-pairwise Fst values and geographic distances, as well as between genetic distances and geographic distances in C. gigantea and C. torulosa, respectively. AMOVA suggested that genetic variation mostly resided within populations. Sixteen naturalpopulations were evidently clustered into two major groups in the constructed neighbour-joining tree. The results demonstrated that C. gigantea and C. torulosa are different Cupressus species. The genetic information provided important theoretical references for conservation and management of the two endangered Cupressus species.


Assuntos
Cupressaceae/classificação , Cupressaceae/genética , Variação Genética , Repetições de Microssatélites , Folhas de Planta/genética , Filogenia , Análise de Sequência de DNA , Tibet
14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(1): 215-220, 2019 Feb.
Artigo em Zh | MEDLINE | ID: mdl-30738473

RESUMO

OBJECTIVE: To establish a novel method to isolate endothelial progenitor cells(EPC) from cryopreserved umbilical cord blood (cryoUCB), to investigate the biological characteristics of EPC and to improve the rate of EPC obtained from cryoUCB. METHODS: Twelve cryoUCB samples during 2000 to 2001 years were collected from allogeneic cord blood bank, cryoUCB was thawed rapidly in a water bath at 37 ℃, total nucleated cells (TNCs) were washed by phosphate-buffered saline (PBS). TNCs were seeded onto fibronectin-coated dishes to isolate EPC. Flow cytometry and immunofluorescence were used to identify EPC. The function of EPC was identified in vitro, such as the incorporation of Dil-Ac-LDL and FITC-UEA-I, the formation of capillary-like structure in matrigel, and the release of VEGF by ELISA. RESULTS: One to five cluster of cobble stone-like cells appeared at 2-3 weeks after seeding. Flow cytometric analysis showed that positive rates of CD31, CD34, CD144, and VEGFR (CD309) were(92.91±5.20)%, (30.0±23.27)%, (88.55±3.83)% and (67.21±12.12)% in passage 1 to passage 3 of EPC. EPC could uptake Dil-Ac-LDL and FITC-UEA-I, form capillary-like network on Matriget and release VEGF. CONCLUSION: EPC had been successfully isolated from cryopreserved umbilical cord blood by this method with high stability and reproducibility. EPC can be obtained in 85% frozen umbilical cord blood. This method may lay a foundation to supply abundant EPC for clinical application.


Assuntos
Células Progenitoras Endoteliais , Sangue Fetal , Diferenciação Celular , Células Cultivadas , Reprodutibilidade dos Testes , Células-Tronco
15.
Genes (Basel) ; 10(12)2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31835855

RESUMO

De novo shoot regeneration is one of the important manifestations of cell totipotency in organogenesis, which reflects a survival strategy organism evolved when facing natural selection. Compared with tissue regeneration, and somatic embryogenesis, de novo shoot regeneration denotes a shoot regeneration process directly from detatched or injured tissues of plant. Studies on plant shoot regeneration had identified key genes mediating shoot regeneration. However, knowledge was derived from Arabidopsis; the regeneration capacity is hugely distinct among species. To achieve a comprehensive understanding of the shoot regeneration mechanism from tree species, we select four genetic lines of Populus euphratica from a natural population to be sequenced at transcriptome level. On the basis of the large difference of differentiation capacity, between the highly differentiated (HD) and low differentiated (LD) groups, the analysis of differential expression identified 4920 differentially expressed genes (DEGs), which were revealed in five groups of expression patterns by clustering analysis. Enrichment showed crucial pathways involved in regulation of regeneration difference, including "plant hormone signal transduction", "cell differentiation", "cellular response to auxin stimulus", and "auxin-activated signaling pathway". The expression of nine genes reported to be associated with shoot regeneration was validated using quantitative real-time PCR (qRT-PCR). For the specificity of regeneration mechanism with P. euphratica, large amount of DEGs involved in "plant-pathogen interaction", ubiquitin-26S proteosome mediated proteolysis pathway, stress-responsive DEGs, and senescence-associated DEGs were summarized to possibly account for the differentiation difference with distinct genotypes of P. euphratica. The result in this study helps screening of key regulators in mediating the shoot differentiation. The transcriptomic characteristic in P. euphratica further enhances our understanding of key processes affecting the regeneration capacity of de novo shoots among distinct species.


Assuntos
Brotos de Planta/genética , Populus/genética , Diferenciação Celular/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Organogênese Vegetal/genética , Reguladores de Crescimento de Plantas/genética , Brotos de Planta/crescimento & desenvolvimento , Populus/crescimento & desenvolvimento , Análise de Sequência de RNA/métodos , Transcriptoma/genética
16.
ACS Chem Neurosci ; 10(6): 2777-2785, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31059226

RESUMO

The aberrant autoxidation of norepinephrine (NE) in the presence of oxygen, which is accelerated by Fe(III), has been linked to the pathogenesis of the Parkinson's disease (PD). Adenosine triphosphate (ATP), as a neurotransmitter whose release can be stimulated by tissue damage and oxidative stress, is co-stored and often co-released with NE in presynaptic terminals. We have shown previously that ATP inhibits the iron-catalyzed dopamine oxidation, thereby decreasing the production of certain neurotoxins such as 6-hydroxydopamine. Whether ATP plays a similar role in Fe(III)-catalyzed NE oxidation and how it maintains the NE stability have not been investigated. Here, we studied the coordination in a ternary complex among NE, Fe(III), and ATP, and found that Fe(III) is coordinated as a octahedral center by NE and ATP. Voltammetry and mass spectrometry were employed to examine this ternary complex's modulation of the NE autoxidation. NE-Fe(III)-ATP plays a protective role to modulate the autoxidation and Fe(III)-catalyzed oxidation of NE. The ternary complex can be detected in the substantia nigra (SN), locus coeruleus (LC), and striatum regions of C57BL/6 wild-type mice. In contrast, the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse brains displayed a significant decrease of the ternary complex in the SN region and an increase in the LC and striatum areas. We posit that the ternary complex is produced by noradrenergic neurons as a protective regulator against neuronal damage and oxidative stress, contributing to the lower vulnerability of LC neurons with respect to that of SN neurons.


Assuntos
Trifosfato de Adenosina/metabolismo , Encéfalo/metabolismo , Compostos Férricos/metabolismo , Neurônios/metabolismo , Norepinefrina/metabolismo , Doença de Parkinson/metabolismo , Trifosfato de Adenosina/química , Animais , Compostos Férricos/química , Camundongos , Camundongos Endogâmicos C57BL , Norepinefrina/química , Oxirredução
17.
Stem Cells Int ; 2018: 4659159, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29765412

RESUMO

INTRODUCTION: Our previous study suggested that NSC-CM (neural stem cell-conditioned medium) inhibited cell apoptosis in vitro. In addition, many studies have shown that neurotrophic factors and microparticles secreted into a conditioned medium by NSCs had neuroprotective effects. Thus, we hypothesized that NSC-CM had the capacity of protecting against cerebral I/R injury. METHODS: Adult male Sprague-Dawley rats receiving middle cerebral artery occlusion surgery as an animal model of cerebral I/R injury were randomly assigned to two groups: the control group and NSC-CM-treated group. 1.5 ml NSC-CM or PBS (phosphate buffer saline) was administrated slowly by tail vein at 3 h, 24 h, and 48 h after ischemia onset. RESULTS: NSC-CM significantly ameliorated neurological defects and reduced cerebral infarct volume, accompanied by preserved mitochondrial ultrastructure. In addition, we also found that NSC-CM significantly inhibited cell apoptosis in the ischemic hemisphere via improving the expression of Bcl-2 (B-cell lymphoma-2). CONCLUSION: NSC-CM might be an alternative and effective therapeutic intervention for ischemic stroke.

18.
Sci Rep ; 7(1): 74, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28250432

RESUMO

Dracocephalum tanguticum Maxim, a Lamiaceae species endemic to the Qinghai-Tibetan Plateau and adjacent regions, is an important ornamental, medicinal and aromatic herb. In this study, a comprehensive transcriptome of 18 libraries from six organs namely, roots, stems, leaves, sepals, flowers and seeds of D. tanguticum were generated. More than 100 Gb of sequence data were obtained and assembled de novo into 187,447 transcripts, including 151,463 unigenes, among which the six organs shared 17.7% (26,841). In addition, all unigenes were assigned to 362 pathways, in which 'biosynthesis of secondary metabolites' is the second enriched pathway. Furthermore, rosmarinic acid (RA) is one of the multifunctional phenolic bioactive compounds produced in some Lamiaceae species. The six organs of D. tanguticum were confirmed to produce RA. A total of 22 predicted biosynthetic genes related to RA from the transcriptome were further isolated. Two of these genes were identified as candidates by evaluating the correlation coefficient between the RA contents and the expression of the predicted biosynthetic genes in the six organs. The new sequence information will improve the knowledge of D. tanguticum, as well as provide a reference tool for future studies of biosynthetic genes related to RA in this species.


Assuntos
Vias Biossintéticas , Cinamatos/metabolismo , Depsídeos/metabolismo , Perfilação da Expressão Gênica/métodos , Lamiaceae/genética , Análise de Sequência de RNA/métodos , Flores/genética , Regulação da Expressão Gênica de Plantas , Lamiaceae/crescimento & desenvolvimento , Especificidade de Órgãos , Folhas de Planta/genética , Proteínas de Plantas/genética , Raízes de Plantas/genética , Caules de Planta/genética , Ácido Rosmarínico
19.
Zhonghua Wei Chang Wai Ke Za Zhi ; 19(1): 54-7, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-26797839

RESUMO

OBJECTIVE: To evaluate the prognosis and predictive values of preoperative Glasgow prognostic score (GPS) for adenocarcinoma of esophagogastric junction(AEG) patients. METHODS: A retrospective study of 322 AEG patients who received operation between January 2007 and March 2010 in Henan Provincial People's Hospital was performed. Clinical data, pathological characteristics, laboratory parameters and survival data were collected. The GPS was calculated based on C-reactive protein(CRP) and serum albumin(ALB) levels. Univariate and multivariate analysis were used to evaluate the prognostic value of GPS. RESULTS: Among 322 patients, 0, 1, 2 of GPS were 192, 104 and 26 patients respectively. The median follow-up was 37 (4-73) months. In Kaplan-Meier analysis, median diseases-free survival (DFS) of GPS 0, 1, 2 was 47.0 (95% CI: 31.6-62.4), 15.0 (95% CI: 11.8-8.2) and 4.7 (95% CI: 3.8-5.6) months (P<0.01), and median overall survival (OS) was out of reach, 20.6 (95% CI: 15.8-25.4) and 7.0 (95% CI: 5.8-8.2) months (P<0.01). Univariate and multivariate analysis revealed that GPS was an independent predictor of DFS (P<0.01) and OS (P<0.01) of AEG. CONCLUSION: GPS is an effective predictor of survival in AEG.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Junção Esofagogástrica , Neoplasias Gástricas , Proteína C-Reativa , Intervalo Livre de Doença , Humanos , Estimativa de Kaplan-Meier , Prognóstico , Estudos Retrospectivos
20.
PLoS One ; 10(1): e111054, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25559297

RESUMO

Sophora moorcroftiana, a Leguminosae shrub species that is restricted to the arid and semi-arid regions of the Qinghai-Tibet Plateau, is an ecologically important foundation species and exhibits substantial drought tolerance in the Plateau. There are no functional genomics resources in public databases for understanding the molecular mechanism underlying the drought tolerance of S. moorcroftiana. Therefore, we performed a large-scale transcriptome sequencing of this species under drought stress using the Illumina sequencing technology. A total of 62,348,602 clean reads were obtained. The assembly of the clean reads resulted in 146,943 transcripts, including 66,026 unigenes. In the assembled sequences, 1534 transcription factors were identified and classified into 23 different common families, and 9040 SSR loci, from di- to hexa-nucleotides, whose repeat number is greater than five, were presented. In addition, we performed a gene expression profiling analysis upon dehydration treatment. The results indicated significant differences in the gene expression profiles among the control, mild stress and severe stress. In total, 4687, 5648 and 5735 genes were identified from the comparison of mild versus control, severe versus control and severe versus mild stress, respectively. Based on the differentially expressed genes, a Gene Ontology annotation analysis indicated many dehydration-relevant categories, including 'response to water 'stimulus' and 'response to water deprivation'. Meanwhile, the Kyoto Encyclopedia of Genes and Genomes pathway analysis uncovered some important pathways, such as 'metabolic pathways' and 'plant hormone signal transduction'. In addition, the expression patterns of 25 putative genes that are involved in drought tolerance resulting from quantitative real-time PCR were consistent with their transcript abundance changes as identified by RNA-seq. The globally sequenced genes covered a considerable proportion of the S. moorcroftiana transcriptome, and the expression results may be useful to further extend the knowledge on the drought tolerance of this plant species that survives under Plateau conditions.


Assuntos
Adaptação Fisiológica/genética , Secas , Regulação da Expressão Gênica de Plantas , Sophora/genética , Transcriptoma , Altitude , Análise por Conglomerados , Ecossistema , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Anotação de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA/métodos , Tibet
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