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1.
Front Immunol ; 15: 1391573, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38799419

RESUMO

Background: Inflammation has been reported to be related to anemia. As a novel inflammatory marker, Systemic immune-inflammation index (SII) has not been studied with Anemia. The aim of this study was to investigate the possible relationship between SII and anemia. Methods: This retrospective cross-sectional survey was conducted using data from the 2005-2018 National Health and Nutrition Examination Survey (NHANES) population. In total, 19851 American adults aged ≥18 years were included. SII was calculated as the platelet count×neutrophil count/lymphocyte count. Anemia was defined as hemoglobin (Hgb) levels of < 13 g/dL in males and < 12 g/dL in females. Logistic regression analyses, subgroup analyses and sensitivity analyses were performed to investigate the relationship between SII and anemia. Results: Our study included a total of 19851 patients, of which 1501 (7.6%) had anemia. After adjusting for all covariates, the multivariate logistic regression analysis showed that a higher SII (In-transform) level was associated with increased likelihood of anemia (OR=1.51, 95% CI: 1.36-1.68, P<0.001). The association between SII and anemia exhibited a nonlinear manner. The positive correlation between SII and anemia was related to the severity of anemia. Subgroup analysis showed that there was no significant dependence on age, family income, body mass index, hypertension, kidney disease and cancer except gender on this positive association. Furthermore, sensitivity analyses confirmed the robustness of our results. Conclusion: Our study demonstrated that SII was positively associated with anemia especially among female participants. And this positive correlation was related to the severity of anemia. Further large-scale prospective studies are still needed to analyze the role of SII in anemia.


Assuntos
Anemia , Inflamação , Humanos , Feminino , Masculino , Anemia/sangue , Anemia/imunologia , Anemia/epidemiologia , Pessoa de Meia-Idade , Estudos Transversais , Adulto , Estudos Retrospectivos , Inflamação/imunologia , Inflamação/sangue , Inquéritos Nutricionais , Idoso , Contagem de Plaquetas , Biomarcadores/sangue , Hemoglobinas/análise , Adulto Jovem , Contagem de Linfócitos
2.
J Mol Cell Biol ; 14(2)2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35022784

RESUMO

The aryl hydrocarbon receptor (AHR) plays an important role during mammalian embryo development. Inhibition of AHR signaling promotes the development of hematopoietic stem/progenitor cells. AHR also regulates the functional maturation of blood cells, such as T cells and megakaryocytes. However, little is known about the role of AHR modulation during the development of erythroid cells. In this study, we used the AHR antagonist StemRegenin 1 (SR1) and the AHR agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin during different stages of human erythropoiesis to elucidate the function of AHR. We found that antagonizing AHR signaling improved the production of human embryonic stem cell derived erythrocytes and enhanced erythroid terminal differentiation. RNA sequencing showed that SR1 treatment of proerythroblasts upregulated the expression of erythrocyte differentiation-related genes and downregulated actin organization-associated genes. We found that SR1 accelerated F-actin remodeling in terminally differentiated erythrocytes, favoring their maturation of the cytoskeleton and enucleation. We demonstrated that the effects of AHR inhibition on erythroid maturation were associated with F-actin remodeling. Our findings help uncover the mechanism for AHR-mediated human erythroid cell differentiation. We also provide a new approach toward the large-scale production of functionally mature human pluripotent stem cell-derived erythrocytes for use in translational applications.


Assuntos
Actinas , Receptores de Hidrocarboneto Arílico , Actinas/metabolismo , Animais , Diferenciação Celular/genética , Eritroblastos/metabolismo , Células-Tronco Hematopoéticas , Humanos , Mamíferos , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo
3.
Stem Cell Reports ; 7(5): 869-883, 2016 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-27720903

RESUMO

The development of human erythroid cells has been mostly examined in models of adult hematopoiesis, while their early derivation during embryonic and fetal stages is largely unknown. We observed the development and maturation of erythroblasts derived from human pluripotent stem cells (hPSCs) by an efficient co-culture system. These hPSC-derived early erythroblasts initially showed definitive characteristics with a glycophorin A+ (GPA+) CD34lowCD36- phenotype and were distinct from adult CD34+ cell-derived ones. After losing CD34 expression, early GPA+CD36- erythroblasts matured into GPA+CD36low/+ stage as the latter expressed higher levels of ß-globin along with a gradual loss of mesodermal and endothelial properties, and terminally suppressed CD36. We establish a unique in vitro model to trace the early development of hPSC-derived erythroblasts by serial expression of CD34, GPA, and CD36. Our findings may provide insight into the understanding of human early erythropoiesis and, ultimately, therapeutic potential.


Assuntos
Antígenos CD34/metabolismo , Antígenos CD36/metabolismo , Diferenciação Celular , Eritroblastos/citologia , Eritroblastos/metabolismo , Glicoforinas/metabolismo , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Biomarcadores , Células Cultivadas , Análise por Conglomerados , Técnicas de Cocultura , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Expressão Gênica , Perfilação da Expressão Gênica , Hematopoese/genética , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Fenótipo , Transdução de Sinais
4.
Biochem J ; 473(14): 2131-9, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27208176

RESUMO

Cell proliferation was inhibited following forced over-expression of miR-30a in the ovary cancer cell line A2780DX5 and the gastric cancer cell line SGC7901R. Interestingly, miR-30a targets the DNA replication protein RPA1, hinders the replication of DNA and induces DNA fragmentation. Furthermore, ataxia telangiectasia mutated (ATM) and checkpoint kinase 2 (CHK2) were phosphorylated after DNA damage, which induced p53 expression, thus triggering the S-phase checkpoint, arresting cell cycle progression and ultimately initiating cancer cell apoptosis. Therefore, forced miR-30a over-expression in cancer cells can be a potential way to inhibit tumour development.


Assuntos
Proliferação de Células/fisiologia , Replicação do DNA/fisiologia , MicroRNAs/fisiologia , Proteína de Replicação A/metabolismo , Apoptose/genética , Apoptose/fisiologia , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Senescência Celular/genética , Senescência Celular/fisiologia , Quinase do Ponto de Checagem 2/genética , Quinase do Ponto de Checagem 2/metabolismo , Ensaio Cometa , Replicação do DNA/genética , Histonas/metabolismo , Humanos , Imuno-Histoquímica , MicroRNAs/genética , MicroRNAs/metabolismo , Interferência de RNA/fisiologia , Proteína de Replicação A/genética
5.
J Fluoresc ; 25(4): 1151-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26162989

RESUMO

The fluorescence spectra, fluorescence quantum yield, and fluorescence lifetime of Acridine Red (AR), Pyronin Y (PYY), and Pyronin B (PYB) in aqueous and organic solvents were measured by steady state fluorescence, time-correlated single photon counting, and electronic absorption methods. The rate constants of radiation and non radiation process (kf and kic) were calculated to elucidate the structural effect on the fluorescence mechanism. The data for each compound are compared with that of the corresponding rhodamine dye. AR showed significant longer lifetime and higher quantum yield than PYY and PYB, because the alkyls on N atom enhance the internal conversion (IC), the longer the alkyl the faster the IC. However, the structural variation does not alter the rate constant of radiation process (kf) but does change kic significantly. The phenyl in Rhodamine B or Rhodamine 6G shows only a slight effect on the fluorescence properties. Ethanol is the solvent in which all five compounds exhibit longest lifetime and highest fluorescence quantum yield.


Assuntos
Corantes/química , Corantes Fluorescentes/química , Pironina/análogos & derivados , Pironina/química , Rodaminas/química , Solventes/química , Água/química , Fluorescência , Modelos Moleculares , Espectrometria de Fluorescência/métodos
6.
Anal Chem ; 85(8): 4007-13, 2013 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-23496088

RESUMO

This study demonstrates the formation of a three-dimensional conducting framework through hybridization of bioelectrochemically active infinite coordination polymer (ICP) nanoparticles with single-walled carbon nanotubes (SWNTs) for highly sensitive and selective in vivo electrochemical monitoring with combination with in vivo microdialysis. The bioelectrochemically active ICP nanoparticles are synthesized through the self-assembly process of NAD(+) and Tb(3+), in which all biosensing elements including an electrocatalyst (i.e., methylene green, MG), cofactor (i.e., ß-nicotinamide adenine dinucleotide, NAD(+)), and enzyme (i.e., glucose dehydrogenase, GDH) are adaptively encapsulated. The ICP/SWNT-based biosensors are simply prepared by drop-coating the as-formed ICP/SWNT nanocomposite onto a glassy carbon substrate. Electrochemical studies demonstrate that the simply prepared ICP/SWNT-based biosensors exhibit excellent biosensing properties with a higher sensitivity and stability than the ICP-based biosensors prepared only with ICP nanoparticles (i.e., without hybridization of SWNTs). By using a GDH-based electrochemical biosensor as an example, we demonstrate a technically simple yet effective online electroanalytical platform for continuously monitoring glucose in the brain of guinea pigs with the ICP/SWNT-based biosensor as an online detector in a continuous-flow system combined with in vivo microdialysis. Under the experimental conditions employed here, the dynamic linear range for glucose with the ICP/SWNT-biosensor is from 50 to 1000 µM. Moreover, in vivo selectivity investigations with the biosensors prepared by the GDH-free ICPs reveal that ICP/SWNT-based biosensors are very selective for the measurement of glucose in the cerebral system. The basal level of glucose in the microdialysates from the striatum of guinea pigs is determined to be 0.31 ± 0.03 mM (n = 3). The study offers a simple route to the preparation of electrochemical biosensors, which is envisaged to be particularly useful for probing the chemical events involved in some physiological and pathological processes.


Assuntos
Técnicas Biossensoriais/métodos , Corpo Estriado/química , Técnicas Eletroquímicas/métodos , Glucose/análise , Nanopartículas/química , Nanotubos de Carbono/química , Animais , Glucose 1-Desidrogenase/química , Cobaias , Masculino , Azul de Metileno/análogos & derivados , Azul de Metileno/química , Microdiálise , Microeletrodos , NAD/química , Polimerização , Sensibilidade e Especificidade , Térbio/química
7.
Analyst ; 138(1): 179-85, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23120750

RESUMO

This study demonstrates a new electrochemical method for continuous neurochemical sensing with a biofuel cell-based self-powered biogenerator as the detector for the analysis of microdialysate continuously sampled from rat brain, with glucose as an example analyte. To assemble a glucose/O(2) biofuel cell that can be used as a self-powered biogenerator for glucose sensing, glucose dehydrogenase (GDH) was used as the bioanodic catalyst for the oxidation of glucose with methylene green (MG) adsorbed onto single-walled carbon nanotubes (SWNTs) as the electrocatalyst for the oxidation of dihydronicotinamide adenine dinucleotide (NADH). Laccase crosslinked onto SWNTs was used as the biocathodic catalyst for the O(2) reduction. To enable the bioanode and biocathode to work efficiently in their individually favorable solutions and to eliminate the interference between the glucose bioanode and O(2) biocathode, the biofuel cell-based biogenerator was built in a co-laminar microfluidic chip so that the bioanodic and biocathodic streams could be independently optimized to provide conditions favorable for each of the bioelectrodes. By using a home-made portable voltmeter to output the voltage generated on an external resistor, the biogenerator was used for glucose sensing based on a galvanic cell mechanism. In vitro experiments demonstrate that, under the optimized conditions, the voltage generated on an external resistor shows a linear relationship with the logarithmic glucose concentration within a concentration range of 0.2 mM to 1.0 mM. Moreover, the biogenerator exhibits a high stability and a good selectivity for glucose sensing. The validity of the biofuel cell-based self-powered biogenerator for continuous neurochemical sensing was illustrated by online continuous monitoring of striatum glucose in rat brain through the combination of in vivo microdialysis. This study offers a new and technically simple platform for continuously monitoring physiologically important species in cerebral systems.


Assuntos
Biocombustíveis , Técnicas Biossensoriais/instrumentação , Encéfalo/metabolismo , Fontes de Energia Elétrica , Neuroquímica/métodos , Animais , Eletroquímica , Glucose/metabolismo , Microdiálise , Neostriado/metabolismo , Sistemas On-Line , Oxigênio/metabolismo , Ratos
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