Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 158
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Cell ; 182(5): 1328-1340.e13, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32814014

RESUMEN

Among arthropod vectors, ticks transmit the most diverse human and animal pathogens, leading to an increasing number of new challenges worldwide. Here we sequenced and assembled high-quality genomes of six ixodid tick species and further resequenced 678 tick specimens to understand three key aspects of ticks: genetic diversity, population structure, and pathogen distribution. We explored the genetic basis common to ticks, including heme and hemoglobin digestion, iron metabolism, and reactive oxygen species, and unveiled for the first time that genetic structure and pathogen composition in different tick species are mainly shaped by ecological and geographic factors. We further identified species-specific determinants associated with different host ranges, life cycles, and distributions. The findings of this study are an invaluable resource for research and control of ticks and tick-borne diseases.


Asunto(s)
Variación Genética/genética , Enfermedades por Picaduras de Garrapatas/microbiología , Garrapatas/genética , Animales , Línea Celular , Vectores de Enfermedades , Especificidad del Huésped/genética
2.
Nat Immunol ; 16(8): 810-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26147687

RESUMEN

Foxm1 is known as a typical proliferation-associated transcription factor. Here we found that Foxm1 was essential for maintenance of the quiescence and self-renewal capacity of hematopoietic stem cells (HSCs) in vivo in mice. Reducing expression of FOXM1 also decreased the quiescence of human CD34(+) HSCs and progenitor cells, and its downregulation was associated with a subset of myelodysplastic syndrome (MDS). Mechanistically, Foxm1 directly bound to the promoter region of the gene encoding the receptor Nurr1 (Nr4a2; called 'Nurr1' here), inducing transcription, while forced expression of Nurr1 reversed the loss of quiescence observed in Foxm1-deficient cells in vivo. Thus, our studies reveal a previously unrecognized role for Foxm1 as a critical regulator of the quiescence and self-renewal of HSCs mediated at least in part by control of Nurr1 expression.


Asunto(s)
Proliferación Celular/genética , Factores de Transcripción Forkhead/genética , Regulación de la Expresión Génica , Células Madre Hematopoyéticas/metabolismo , Animales , Células Cultivadas , Citometría de Flujo , Proteína Forkhead Box M1 , Factores de Transcripción Forkhead/metabolismo , Perfilación de la Expresión Génica , Células HEK293 , Humanos , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/metabolismo , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Regiones Promotoras Genéticas/genética , Unión Proteica , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
3.
Proc Natl Acad Sci U S A ; 121(10): e2319366121, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38422020

RESUMEN

Acute myeloid leukemia (AML) is an aging-related and heterogeneous hematopoietic malignancy. In this study, a total of 1,474 newly diagnosed AML patients with RNA sequencing data were enrolled, and targeted or whole exome sequencing data were obtained in 94% cases. The correlation of aging-related factors including age and clonal hematopoiesis (CH), gender, and genomic/transcriptomic profiles (gene fusions, genetic mutations, and gene expression networks or pathways) was systematically analyzed. Overall, AML patients aged 60 y and older showed an apparently dismal prognosis. Alongside age, the frequency of gene fusions defined in the World Health Organization classification decreased, while the positive rate of gene mutations, especially CH-related ones, increased. Additionally, the number of genetic mutations was higher in gene fusion-negative (GF-) patients than those with GF. Based on the status of CH- and myelodysplastic syndromes (MDS)-related mutations, three mutant subgroups were identified among the GF- AML cohort, namely, CH-AML, CH-MDS-AML, and other GF- AML. Notably, CH-MDS-AML demonstrated a predominance of elderly and male cases, cytopenia, and significantly adverse clinical outcomes. Besides, gene expression networks including HOXA/B, platelet factors, and inflammatory responses were most striking features associated with aging and poor prognosis in AML. Our work has thus unraveled the intricate regulatory circuitry of interactions among different age, gender, and molecular groups of AML.


Asunto(s)
Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Anciano , Humanos , Masculino , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Envejecimiento/genética , Mutación , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/patología , Pronóstico
4.
Proc Natl Acad Sci U S A ; 119(49): e2211429119, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36442087

RESUMEN

The current classification of acute myeloid leukemia (AML) relies largely on genomic alterations. Robust identification of clinically and biologically relevant molecular subtypes from nongenomic high-throughput sequencing data remains challenging. We established the largest multicenter AML cohort (n = 655) in China, with all patients subjected to RNA sequencing (RNA-Seq) and 619 (94.5%) to targeted or whole-exome sequencing (TES/WES). Based on an enhanced consensus clustering, eight stable gene expression subgroups (G1-G8) with unique clinical and biological significance were identified, including two unreported (G5 and G8) and three redefined ones (G4, G6, and G7). Apart from four well-known low-risk subgroups including PML::RARA (G1), CBFB::MYH11 (G2), RUNX1::RUNX1T1 (G3), biallelic CEBPA mutations or -like (G4), four meta-subgroups with poor outcomes were recognized. The G5 (myelodysplasia-related/-like) subgroup enriched clinical, cytogenetic and genetic features mimicking secondary AML, and hotspot mutations of IKZF1 (p.N159S) (n = 7). In contrast, most NPM1 mutations and KMT2A and NUP98 fusions clustered into G6-G8, showing high expression of HOXA/B genes and diverse differentiation stages, from hematopoietic stem/progenitor cell down to monocyte, namely HOX-primitive (G7), HOX-mixed (G8), and HOX-committed (G6). Through constructing prediction models, the eight gene expression subgroups could be reproduced in the Cancer Genome Atlas (TCGA) and Beat AML cohorts. Each subgroup was associated with distinct prognosis and drug sensitivities, supporting the clinical applicability of this transcriptome-based classification of AML. These molecular subgroups illuminate the complex molecular network of AML, which may promote systematic studies of disease pathogenesis and foster the screening of targeted agents based on omics.


Asunto(s)
Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Humanos , Transcriptoma , Leucemia Mieloide Aguda/genética , Diferenciación Celular/genética , Células Madre Hematopoyéticas
5.
Proc Natl Acad Sci U S A ; 119(15): e2120787119, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35385357

RESUMEN

T cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological malignancy of T cell progenitors, known to be a heterogeneous disease in pediatric and adult patients. Here we attempted to better understand the disease at the molecular level based on the transcriptomic landscape of 707 T-ALL patients (510 pediatric, 190 adult patients, and 7 with unknown age; 599 from published cohorts and 108 newly investigated). Leveraging the information of gene expression enabled us to identify 10 subtypes (G1­G10), including the previously undescribed one characterized by GATA3 mutations, with GATA3R276Q capable of affecting lymphocyte development in zebrafish. Through associating with T cell differentiation stages, we found that high expression of LYL1/LMO2/SPI1/HOXA (G1­G6) might represent the early T cell progenitor, pro/precortical/cortical stage with a relatively high age of disease onset, and lymphoblasts with TLX3/TLX1 high expression (G7­G8) could be blocked at the cortical/postcortical stage, while those with high expression of NKX2-1/TAL1/LMO1 (G9­G10) might correspond to cortical/postcortical/mature stages of T cell development. Notably, adult patients harbored more cooperative mutations among epigenetic regulators, and genes involved in JAK-STAT and RAS signaling pathways, with 44% of patients aged 40 y or above in G1 bearing DNMT3A/IDH2 mutations usually seen in acute myeloid leukemia, suggesting the nature of mixed phenotype acute leukemia.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células T Precursoras , Transcriptoma , Niño , Humanos , Mutación , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética
6.
Haematologica ; 109(2): 411-421, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37584287

RESUMEN

Leukemia stem cells (LSC) represent a crucial and rare subset of cells present in acute myeloid leukemia (AML); they play a pivotal role in the initiation, maintenance, and relapse of this disease. Targeting LSC holds great promise for preventing AML relapse and improving long-term outcomes. However the precise molecular mechanisms governing LSC self-renewal are still poorly understood. Here, we present compelling evidence that the expression of miR-30e-5p, a potential tumor-suppressive microRNA, is significantly lower in AML samples than in healthy bone marrow samples. Forced expression of miR- 30e effectively inhibits leukemogenesis, impairs LSC self-renewal, and delays leukemia progression. Mechanistically, Cyb561 acts as a direct target of miR-30e-5p in LSC, and its deficiency restricts the self-renewal of LSC by activating reactive oxygen series signaling and markedly prolongs recipients' survival. Moreover, genetic or pharmacological overexpression of miR-30e-5p or knockdown of Cyb561 suppresses the growth of human AML cells. In conclusion, our findings establish the crucial role of the miR-30e-5p/Cyb561/ROS axis in finely regulating LSC self-renewal, highlighting Cyb561 as a potential therapeutic target for LSC-directed therapies.


Asunto(s)
Leucemia Mieloide Aguda , MicroARNs , Humanos , Especies Reactivas de Oxígeno , Autorrenovación de las Células/genética , MicroARNs/genética , Transducción de Señal , Recurrencia , Proliferación Celular/genética , Línea Celular Tumoral
7.
J Environ Manage ; 353: 120113, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38286069

RESUMEN

The growing incidence of urban flood disasters poses a major challenge to urban sustainability in China. Previous studies have reported that climate change and urbanization exacerbate urban flood risk in some major cities of China. However, few assessments have quantified the contributions of these two factors to urban flood changes in recent decades at the nationwide scale. Here, surface runoff caused by precipitation extremes was used as the urban flood hazard to evaluate the impacts of climate change and urbanization in China's 293 major cities. This study assessed the contributions of these drivers to urban flood hazard changes and identified the hotspot cities with increased trends under both factors during the past four decades (1980-2019). The results showed that approximately 70% of the cities analyzed have seen an increase of urban flood hazard in the latest decade. Urbanization made a positive contribution to increased urban flood hazards in more than 90% of the cities. The contribution direction of climate change showed significant variations across China. Overall, the absolute contribution rate of climate change far outweighed that of urbanization. In half of the cities (mainly distributed in eastern China), both climate change and urbanization led to increased urban flood hazard over the past decade. Among them, 33 cities have suffered a consecutive increase in urban flood hazard driven by both factors.


Asunto(s)
Inundaciones , Urbanización , Ciudades , Cambio Climático , Crecimiento Sostenible , China
8.
Blood ; 137(5): 610-623, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33538795

RESUMEN

This study was conducted to determine the dosage effect of c-Myc on hematopoiesis and its distinct role in mediating the Wnt/ß-catenin pathway in hematopoietic stem cell (HSC) and bone marrow niche cells. c-Myc haploinsufficiency led to ineffective hematopoiesis by inhibiting HSC self-renewal and quiescence and by promoting apoptosis. We have identified Nr4a1, Nr4a2, and Jmjd3, which are critical for the maintenance of HSC functions, as previously unrecognized downstream targets of c-Myc in HSCs. c-Myc directly binds to the promoter regions of Nr4a1, Nr4a2, and Jmjd3 and regulates their expression. Our results revealed that Nr4a1 and Nr4a2 mediates the function of c-Myc in regulating HSC quiescence, whereas all 3 genes contribute to the function of c-Myc in the maintenance of HSC survival. Adenomatous polyposis coli (Apc) is a negative regulator of the Wnt/ß-catenin pathway. We have provided the first evidence that Apc haploinsufficiency induces a blockage of erythroid lineage differentiation through promoting secretion of IL6 in bone marrow endothelial cells. We found that c-Myc haploinsufficiency failed to rescue defective function of Apc-deficient HSCs in vivo but it was sufficient to prevent the development of severe anemia in Apc-heterozygous mice and to significantly prolong the survival of those mice. Furthermore, we showed that c-Myc-mediated Apc loss induced IL6 secretion in endothelial cells, and c-Myc haploinsufficiency reversed the negative effect of Apc-deficient endothelial cells on erythroid cell differentiation. Our studies indicate that c-Myc has a context-dependent role in mediating the function of Apc in hematopoiesis.


Asunto(s)
Genes myc , Hematopoyesis/fisiología , Proteínas Proto-Oncogénicas c-myb/fisiología , Proteína de la Poliposis Adenomatosa del Colon/fisiología , Anemia/genética , Anemia/prevención & control , Animales , Apoptosis/fisiología , Trasplante de Médula Ósea , Autorrenovación de las Células/fisiología , Ensayo de Unidades Formadoras de Colonias , Células Endoteliales/patología , Células Eritroides/patología , Eliminación de Gen , Genes APC , Haploinsuficiencia , Hematopoyesis/genética , Células Madre Hematopoyéticas , Interleucina-6/fisiología , Histona Demetilasas con Dominio de Jumonji/fisiología , Ratones Mutantes , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/fisiología , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/fisiología , Poli I-C/farmacología , Quimera por Radiación , Vía de Señalización Wnt/fisiología
9.
Blood ; 138(26): 2838-2852, 2021 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-34255814

RESUMEN

YTHDC1 has distinct functions as a nuclear N6-methyladenosine (m6A) reader in regulating RNA metabolism. Here we show that YTHDC1 is overexpressed in acute myeloid leukemia (AML) and that it is required for the proliferation and survival of human AML cells. Genetic deletion of Ythdc1 markedly blocks AML development and maintenance as well as self-renewal of leukemia stem cells (LSCs) in vivo in mice. We found that Ythdc1 is also required for normal hematopoiesis and hematopoietic stem and progenitor cell (HSPC) maintenance in vivo. Notably, Ythdc1 haploinsufficiency reduces self-renewal of LSCs but not HSPCs in vivo. YTHDC1 knockdown has a strong inhibitory effect on proliferation of primary AML cells. Mechanistically, YTHDC1 regulates leukemogenesis through MCM4, which is a critical regulator of DNA replication. Our study provides compelling evidence that shows an oncogenic role and a distinct mechanism of YTHDC1 in AML.


Asunto(s)
Regulación Leucémica de la Expresión Génica , Leucemia Mieloide Aguda/genética , Proteínas de Mantenimiento de Minicromosoma/genética , Proteínas del Tejido Nervioso/genética , Factores de Empalme de ARN/genética , Adenosina/análogos & derivados , Adenosina/genética , Animales , Carcinogénesis/genética , Línea Celular Tumoral , Replicación del ADN , Humanos , Ratones Transgénicos , Componente 4 del Complejo de Mantenimiento de Minicromosoma/genética , Regulación hacia Arriba
10.
BMC Public Health ; 23(1): 1747, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37679728

RESUMEN

OBJECTIVE: The objective of this study is to explore the relationship between family communication, family violence, problematic internet use, anxiety, and depression and validate their potential mediating role. METHODS: The study population consisted of Chinese adolescents aged 12 to 18 years, and a cross-sectional survey was conducted in 2022. Structural equation models were constructed using AMOS 25.0 software to examine the factors that influence adolescent anxiety and depression and the mediating effects of problematic internet use and family violence. RESULTS: The results indicate that family communication was significantly and negatively related to family violence (ß = -.494, p < 0.001), problematic internet use (ß = -.056, p < .05), depression (ß = -.076, p < .01), and anxiety (ß = -.071, p < .05). And the finds also indicate that family violence mediated the relationships between family communication and depression (ß = -.143, CI: -.198 -.080), and between family communication and anxiety (ß = -.141; CI: -.198 -.074). Chain indirect effects between family communication and depression (ß = -.051; CI: -.081 -.030) or anxiety (ß = -.046; CI: -.080 -.043) via family violence and then through problematic internet use were also found in the present study. CONCLUSIONS: In conclusion, positive family communication is crucial in reducing anxiety and depression in adolescents. Moreover, problematic internet use and family violence mediate the effects of positive family communication on anxiety and depression. Therefore, improving family communication and promoting interventions aimed at reducing family violence and problematic internet use can help reduce anxiety and depression in adolescents, thus promoting their healthy development.


Asunto(s)
Depresión , Uso de Internet , Adolescente , Humanos , Estudios Transversales , Depresión/epidemiología , Ansiedad/epidemiología , Comunicación
11.
Hereditas ; 160(1): 37, 2023 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-37978541

RESUMEN

Interstitial lung diseases (ILDs), or diffuse pulmonary lung disease, are a subset of lung diseases that primarily affect lung alveoli and the space around interstitial tissue and bronchioles. It clinically manifests as progressive dyspnea, and patients often exhibit a varied decrease in pulmonary diffusion function. Recently, variants in telomere biology-related genes have been identified as genetic lesions of ILDs. Here, we enrolled 82 patients with interstitial pneumonia from 2017 to 2021 in our hospital to explore the candidate gene mutations of these patients via whole-exome sequencing. After data filtering, a novel heterozygous mutation (NM_025099: p.Gly131Arg) of CTC1 was identified in two affected family members. As a component of CST (CTC1-STN1-TEN1) complex, CTC1 is responsible for maintaining telomeric structure integrity and has also been identified as a candidate gene for IPF, a special kind of chronic ILD with insidious onset. Simultaneously, real-time PCR revealed that two affected family members presented with short telomere lengths, which further confirmed the effect of the mutation in the CTC1 gene. Our study not only expanded the mutation spectrum of CTC1 and provided epidemiological data on ILDs caused by CTC1 mutations but also further confirmed the relationship between heterozygous mutations in CTC1 and ILDs, which may further contribute to understanding the mechanisms underlying ILDs.


Asunto(s)
Enfermedades Pulmonares Intersticiales , Acortamiento del Telómero , Humanos , Proteínas de Unión a Telómeros/genética , Proteínas de Unión a Telómeros/metabolismo , Pueblos del Este de Asia , Mutación , Enfermedades Pulmonares Intersticiales/genética , Telómero/genética
12.
J Craniofac Surg ; 34(2): e139-e141, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36731099

RESUMEN

Salivary fistula is a common postparotidectomy complication, and eating sour or spicy food ranks among the leading causes. Here we report a rare postparotidectomy salivary fistula case, a 31-year-old female patient who affirmed that she did not eat any irritating foods but admitted that she had been watching food videos for up to 4 hours every day since she left hospital. This case offers a cautionary tale about postparotidectomy precautions.


Asunto(s)
Fístula , Fístula de las Glándulas Salivales , Femenino , Humanos , Adulto , Fístula de las Glándulas Salivales/etiología , Fístula/complicaciones
14.
Circ Res ; 123(1): 43-56, 2018 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-29794022

RESUMEN

RATIONALE: Microvascular inflammation and endothelial dysfunction secondary to unchecked activation of endothelium play a critical role in the pathophysiology of sepsis and organ failure. The intrinsic signaling mechanisms responsible for dampening excessive activation of endothelial cells are not completely understood. OBJECTIVE: To determine the central role of YAP (Yes-associated protein), the major transcriptional coactivator of the Hippo pathway, in modulating the strength and magnitude of endothelial activation and vascular inflammation. METHODS AND RESULTS: Endothelial-specific YAP knockout mice showed increased basal expression of E-selectin and ICAM (intercellular adhesion molecule)-1 in endothelial cells, a greater number of adherent neutrophils in postcapillary venules and increased neutrophil counts in bronchoalveolar lavage fluid. Lipopolysaccharide challenge of these mice augmented NF-κB (nuclear factor-κB) activation, expression of endothelial adhesion proteins, neutrophil and monocyte adhesion to cremaster muscle venules, transendothelial neutrophil migration, and lung inflammatory injury. Deletion of YAP in endothelial cells also markedly augmented the inflammatory response and cardiovascular dysfunction in a polymicrobial sepsis model induced by cecal ligation and puncture. YAP functioned by interacting with the E3 ubiquitin-protein ligase TLR (Toll-like receptor) signaling adaptor TRAF6 (tumor necrosis factor receptor-associated factor 6) to ubiquitinate TRAF6, and thus promoted TRAF6 degradation and modification resulting in inhibition of NF-κB activation. TRAF6 depletion in endothelial cells rescued the augmented inflammatory phenotype in mice with endothelial cell-specific deletion of YAP. CONCLUSIONS: YAP modulates the activation of endothelial cells and suppresses vascular inflammation through preventing TRAF6-mediated NF-κB activation and is hence essential for limiting the severity of sepsis-induced inflammation and organ failure.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/fisiología , Células Endoteliales/fisiología , Endotelio Vascular/fisiopatología , Fosfoproteínas/fisiología , Factor 6 Asociado a Receptor de TNF/metabolismo , Vasculitis/etiología , Proteínas Adaptadoras Transductoras de Señales/deficiencia , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Permeabilidad Capilar , Adhesión Celular , Proteínas de Ciclo Celular , Selectina E/metabolismo , Células Endoteliales/citología , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Molécula 1 de Adhesión Intercelular/metabolismo , Recuento de Leucocitos , Ratones , Ratones Noqueados , Microvasos , Monocitos/fisiología , FN-kappa B/metabolismo , Neutrófilos/citología , Fosfoproteínas/deficiencia , Fosfoproteínas/genética , Sepsis/complicaciones , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Vénulas/citología , Proteínas Señalizadoras YAP
15.
Mol Cancer ; 18(1): 30, 2019 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-30813931

RESUMEN

Ectopic Viral Integration site 1 (EVI1) upregulation is implicated in 10-25% of pediatric acute myeloid leukemia (AML) and has an inferior outcome with current chemotherapy regimens. Here we report that EVI1 upregulation is associated with methylation of the miR-9 promoter and correlated with downregulation of miR-9 in human AML cell lines and bone marrow (BM) cells from pediatric patients. Reactivation of miR-9 by hypomethylating agents and forced expression of miR-9 in EVI1high leukemia cell lines and primary leukemia cells results in apoptosis and decreased proliferation of EVI1high leukemia cells. Furthermore, re-expression of miR-9 delays disease progression in EVI1high leukemia-xenograft mice. Our results suggest that EVI1-induced hypermethylation and downregulation of the miR-9 plays an important role in leukemogenesis in EVI-1high pediatric AML, indicating that hypomethylating agents may be a potential therapeutic strategy for EVI1high pediatric AML.


Asunto(s)
Epigénesis Genética , Regulación Leucémica de la Expresión Génica , Leucemia Mieloide Aguda/genética , Proteína del Locus del Complejo MDS1 y EV11/genética , MicroARNs/genética , Animales , Antimetabolitos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/genética , Línea Celular Tumoral , Proliferación Celular , Niño , Metilación de ADN/efectos de los fármacos , Decitabina/farmacología , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/mortalidad , Leucemia Mieloide Aguda/patología , Proteína del Locus del Complejo MDS1 y EV11/metabolismo , Ratones , MicroARNs/agonistas , MicroARNs/antagonistas & inhibidores , MicroARNs/metabolismo , Oligorribonucleótidos/genética , Oligorribonucleótidos/metabolismo , Transducción de Señal , Análisis de Supervivencia , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Chembiochem ; 20(18): 2383-2389, 2019 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-30974044

RESUMEN

The design of improved synthetic components is an important research field in synthetic biology. The terminator, responsible for terminating gene transcription, is a necessary component for yeast gene expression. The efficiency element, the positioning element and the poly(A) site have been identified as the constituent parts necessary for the yeast terminator to perform its function. However, the functions of linker 1 (situated between the efficiency element and the positioning element) and linker 2 [between the positioning element and the poly(A) site] in the terminator are still controversial. Here, we have thus designed and synthesized a yeast synthetic terminator library incorporating random 10 bp linker 1 units. For indirect characterization of the strengths of 266 synthetic terminators with the aid of the enhanced green fluorescent protein (eGFP), their fluorescence intensity (FI) values were determined; they ranged from 2.3648 to 3.5270, thus indicating that the strength of yeast terminator can be finely adjusted by changing the linker 1 sequence. The strength increased with decreasing GC content in linker 1, with a T-rich linker 1 helping to enhance terminator strength further. Reducing the stem length can increase the gene expression in cases of weak and medium-strength terminators but decreases the gene expression of strong terminators. Deletion of linker 2 seems to have a positive effect on weak and medium-strength terminators. Construction of a lycopene biosynthesis pathway with synthetic terminators effectively regulated lycopene synthesis, thus indicating that it is highly feasible to use terminators for fine regulation of gene and pathway expression.


Asunto(s)
ADN/genética , Expresión Génica , Regiones Terminadoras Genéticas , Ingeniería Celular/métodos , ADN/síntesis química , Biblioteca de Genes , Secuencias Invertidas Repetidas , Licopeno/metabolismo , Prueba de Estudio Conceptual , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
18.
Arterioscler Thromb Vasc Biol ; 38(1): 64-75, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29025707

RESUMEN

OBJECTIVE: Disturbed flow (DF) is well-known to induce endothelial dysfunction and synergistically with plasma dyslipidemia facilitate plaque formation. Little is known, however, about the synergistic impact of DF and dyslipidemia on endothelial biomechanics. Our goal was to determine the impact of DF on endothelial stiffness and evaluate the role of dyslipidemia/oxLDL (oxidized low-density lipoprotein) in this process. APPROACH AND RESULTS: Endothelial elastic modulus of intact mouse aortas ex vivo and of human aortic endothelial cells exposed to laminar flow or DF was measured using atomic force microscopy. Endothelial monolayer of the aortic arch is found to be significantly stiffer than the descending aorta (4.2+1.1 versus 2.5+0.2 kPa for aortic arch versus descending aorta) in mice maintained on low-fat diet. This effect is significantly exacerbated by short-term high-fat diet (8.7+2.5 versus 4.5+1.2 kPa for aortic arch versus descending aorta). Exposure of human aortic endothelial cells to DF in vitro resulted in 50% increase in oxLDL uptake and significant endothelial stiffening in the presence but not in the absence of oxLDL. DF also increased the expression of oxLDL receptor CD36 (cluster of differentiation 36), whereas downregulation of CD36 abrogated DF-induced endothelial oxLDL uptake and stiffening. Furthermore, genetic deficiency of CD36 abrogated endothelial stiffening in the aortic arch in vivo in mice fed either low-fat diet or high-fat diet. We also show that the loss of endothelial stiffening in CD36 knockout aortas is not mediated by the loss of CD36 in circulating cells. CONCLUSIONS: DF facilitates endothelial CD36-dependent uptake of oxidized lipids resulting in local increase of endothelial stiffness in proatherogenic areas of the aorta.


Asunto(s)
Aorta/metabolismo , Enfermedades de la Aorta/metabolismo , Aterosclerosis/metabolismo , Antígenos CD36/metabolismo , Dislipidemias/metabolismo , Células Endoteliales/metabolismo , Endotelio Vascular/metabolismo , Lipoproteínas LDL/metabolismo , Rigidez Vascular , Animales , Aorta/patología , Aorta/fisiopatología , Enfermedades de la Aorta/patología , Enfermedades de la Aorta/fisiopatología , Aterosclerosis/patología , Aterosclerosis/fisiopatología , Transporte Biológico , Antígenos CD36/deficiencia , Antígenos CD36/genética , Células Cultivadas , Modelos Animales de Enfermedad , Dislipidemias/patología , Dislipidemias/fisiopatología , Módulo de Elasticidad , Células Endoteliales/patología , Endotelio Vascular/patología , Endotelio Vascular/fisiopatología , Humanos , Ratones Noqueados , Flujo Sanguíneo Regional , Transducción de Señal , Regulación hacia Arriba
19.
Med Sci Monit ; 25: 4639-4647, 2019 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-31228347

RESUMEN

BACKGROUND Breast cancer is one of the most malignant tumors worldwide. The natural flavonoid diosmetin has been reported to exhibit various pharmacological activities, including anti-cancer effects. This study aimed to investigate the anti-breast cancer effects of diosmetin on MDA-MB-231 cells and to explore the underlying molecular mechanisms of cell apoptosis. MATERIAL AND METHODS The MDA-MB-231 cells were incubated with diosmetin for 24 h. Then, cell viability and lactate dehydrogenase (LDH) leakage were detected using CCK-8 and LDH assay kits, respectively. Inverted fluorescence microscopy and flow cytometry were used to measure the mitochondrial membrane potential (MMP) and intracellular reactive oxygen species (ROS). Cell apoptosis and cell cycle were determined by flow cytometry. The expressions of apoptosis and cell cycle-related genes were determined by Western blotting and qRT-PCR. RESULTS The results revealed that diosmetin exerts significant cytotoxic effects on MDA-MB-231 cells, as indicated by decreased cell viability, increased intracellular ROS accumulation and LDH release, as well as cell cycle arrest in G0/G1 phase, inducing mitochondrial dysfunction and apoptosis. Moreover, diosmetin treatment significantly downregulated the expression levels of Bcl-2 and Cyclin D1, and upregulated that of p53, Bax, caspase 3, cleaved caspase 9, and cleaved caspase 3. CONCLUSIONS These findings demonstrate that diosmetin has anti-proliferative and pro-apoptotic activities against MDA-MB-231 cells via cell cycle arrest and the mitochondria-mediated intrinsic apoptotic pathway. Our results extend the understanding of the anti-tumor mechanism of diosmetin and suggest that it may be of use as an active natural agent for the prevention or treatment of human breast cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Flavonoides/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Citocromos c/metabolismo , Femenino , Flavonoides/metabolismo , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína X Asociada a bcl-2/metabolismo
20.
Sensors (Basel) ; 19(3)2019 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-30759874

RESUMEN

Objectives: It has been reported recently that gamma measures of the electroencephalogram (EEG) might provide information about the candidate biomarker of mental diseases like schizophrenia, Alzheimer's disease, affective disorder and so on, but as we know it is a difficult issue to induce visual and tactile evoked responses at high frequencies. Although a high-frequency response evoked by auditory senses is achievable, the quality of the recording response is not ideal, such as relatively low signal-to-noise ratio (SNR). Recently, auditory steady-state responses (ASSRs) play an essential role in the field of basic auditory studies and clinical uses. However, how to improve the quality of ASSRs is still a challenge which researchers have been working on. This study aims at designing a more comfortable and suitable evoked paradigm and then enhancing the quality of the ASSRs in healthy subjects so as to further apply it in clinical practice. Methods: Chirp and click stimuli with 40 Hz and 60 Hz were employed to evoke the gamma-ASSR respectively, and the sound adjusted to 45 dB sound pressure level (SPL). Twenty healthy subjects with normal-hearing participated, and 64-channel EEGs were simultaneously recorded during the experiment. Event-related spectral perturbation (ERSP) and SNR of the ASSRs were measured and analyzed to verify the feasibility and adaptability of the proposed evoked paradigm. Results: The results showed that the evoked paradigm proposed in this study could enhance ASSRs with strong feasibility and adaptability. 1) ASSR waves in time domain indicated that 40 Hz stimuli could significantly induce larger peak-to-peak values of ASSRs compared to 60 Hz stimuli (p < 0.01**); ERSP showed that obvious ASSRs were obtained at each lead for both 40 Hz and 60 Hz, as well as the click and chirp stimuli. 2) The SNR of the ASSRs were ⁻3.23 ± 1.68, ⁻2.44 ± 2.90, ⁻4.66 ± 2.09, and ⁻3.53 ± 3.49 respectively for 40 Hz click, 40 Hz chirp, 60 Hz click and 60 Hz chirp, indicating the chirp stimuli could induce significantly better ASSR than the click, and 40 Hz ASSRs had the higher SNR than 60 Hz (p < 0.01**). Limitation: In this study, sample size was small and the age span was not large enough. Conclusions: This study verified the feasibility and adaptability of the proposed evoked paradigm to improve the quality of the gamma-ASSR, which is significant in clinical application. The results suggested that 40 Hz ASSR evoked by chirp stimuli had the best performance and was expected to be used in clinical practice, especially in the field of mental diseases such as schizophrenia, Alzheimer's disease, and affective disorder.


Asunto(s)
Estimulación Acústica/métodos , Electroencefalografía/métodos , Potenciales Evocados Auditivos/fisiología , Adulto , Femenino , Humanos , Masculino , Relación Señal-Ruido , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA