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1.
Inorg Chem ; 62(17): 6544-6548, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37067156

RESUMEN

Two new functionalized platinum(II) rectangles, Pt1 and Pt2, were designed and synthesized from phenanthro crown ether- and biphenyl polyether-bridged bicarboxylate ligands, respectively. The fluorescence titration study of rectangles Pt1 and Pt2 with alkali- and alkaline-earth-metal cations indicated that Pt1 can selectively recognize Na+, while Pt2 has selective binding ability for Mg2+. These selectivity findings suggest that the comparative size and conformational nature of the polyether receptor cavity have a crucial influence on the cation selection.

2.
Inorg Chem ; 62(23): 8784-8788, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37253277

RESUMEN

Herein we report the structural change and radical generation of a cadmium-based metal-organic framework (Cd-MOF) induced by external electric fields. Under a weaker single electric field, different coordination modes of Cd-L lead to 3D → 2D structural change. Under stronger superposed electric fields, Cd-MOF was excited to produce a stable free radical. This study will provide a new avenue for the controlled assembly of MOFs.

3.
Inorg Chem ; 61(34): 13261-13265, 2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-35983996

RESUMEN

Three [Fe2S2-Agx]-hydrogenase active-site-containing coordination polymers (CPs), {[Fe2S2-Ag1](4-cpmt)2(CO)6(ClO4-)}n (1), {[Fe2S2-Ag2](4-cpmt)2(CO)6(OTf-)2(benzene)}n (2), and {[Fe2S2-Ag2](3-cpmt)2(CO)6(ClO4-)2}n (3), were obtained by a direct synthesis method from ligands [FeFe](4-cpmt)2(CO)6 [L1; 4-cpmt = (4-cyanophenyl)methanethiolate] and [FeFe](3-cpmt)2(CO)6 [L2; 3-cpmt = (3-cyanophenyl)methanethiolate] with silver salts. 1-3 represent the first examples of [FeFe]-hydrogenase-based CPs. It was worth noting that the Ag-S bonding between the Ag centers and S atoms of a [Fe2S2] cluster produced a novel [Fe2S2-Agx] (x = 1 or 2) catalytic site in all three polymers. The results of photochemical H2 generation experiments indicated that 2 and 3 containing [Fe2S2-Ag2] active sites showed obviously improved catalytic performances compared with ligands L1 and L2 and [Fe2S2-Ag1]-containing 1. This work provides a pioneering strategy for the direct synthesis of [Fe2S2]-based CPs or metal-organic frameworks.


Asunto(s)
Hidrogenasas , Proteínas Hierro-Azufre , Catálisis , Dominio Catalítico , Ligandos , Polímeros
4.
Mol Pharm ; 15(9): 3931-3945, 2018 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-30011215

RESUMEN

Emodin is a main anthraquinone compound which exists in Chinese traditional medicines including Polygonum multiflorum and Rhubarb. It is documented to have obvious liver and kidney toxicity. This study aims to (a) estimate gender differences of the hepatotoxicity and toxicokinetics in rats after oral administration of emodin (60 and 150 mg/kg/d) for a consecutive 28 days and (b) clarify relative mechanisms caused by glucuronidation and disposition. Hepatotoxicity was significantly higher in female rats than that in male rats, as evidenced by histopathological and biochemical tests. Similarly, the toxicokinetic profiles of emodin have time and gender differences, which could cause time and gender differences in hepatotoxicity. The metabolic and transcriptomics data of 55 human liver and 36 human kidney samples demonstrated that UDP-glucuronosyltransferase 2B7 (UGT2B7) was the predominant enzyme for emodin glucuronidation. A genome-wide association study (GWAS) identified that rs11726899 located within ∼50 kb of the transcript of UGT2B could significantly affect emodin metabolism. Knockdown of UGT2B7 in HepG2 cells significantly decreased emodin glucuronidation and increased cytotoxicity of emodin. The gene expression and protein levels of UGT2B7 were decreased, but those of the multidrug-resistant-protein 2 (MRP2) were increased in HepG2 cells after being treated with 50 µM emodin for 48 h. Long-term use of emodin could decrease the intrinsic clearance (CLint, decreased by 18.5%-35.4%) values of zidovidue (UGT2B7 substrate) glucuronide in both male and female liver microsomes from rats administrated with emodin for 28 days, thus causing the accumulation of emodin. However, higher self-induced MRP2 expression and lower hepatotoxicity were observed in emodin-treated male rats compared to that in female rats. Therefore, gender differences in the hepatotoxicity and toxicokinetics of emodin are potentially mediated by the coupling of UGT2B7 and MRP2 in vivo.


Asunto(s)
Emodina/metabolismo , Animales , Western Blotting , Emodina/farmacocinética , Femenino , Estudio de Asociación del Genoma Completo , Genotipo , Glucuronosiltransferasa/genética , Glucuronosiltransferasa/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Técnicas In Vitro , Riñón/metabolismo , Hígado/metabolismo , Masculino , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Polimorfismo de Nucleótido Simple/genética , Control de Calidad , ARN Interferente Pequeño/metabolismo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores Sexuales , Toxicocinética
5.
Chem Sci ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39165725

RESUMEN

The design of stable and active alternative catalysts to iridium oxide for the anodic oxygen evolution reaction (OER) has been a long pursuit in acidic water splitting. Tantalum pentoxide (Ta2O5) has the merit of great acidic stability but poor OER performance, yet strategies to improve its intrinsic OER activity are highly desirable. Herein, by using density functional theory (DFT) calculations combined with aqueous stability assessment from surface Pourbaix diagrams, we systematically evaluated the OER activity and acidic stability of 14 different metal-doped Ta2O5 catalysts. Apart from the experimentally reported Ir-doped Ta2O5, we computationally identified Ru- and Nb-doped Ta2O5 catalysts as another two candidates with reasonably high stability and activity in acidic OER. Our study also underscores the essence of considering stable surface states of catalysts under working conditions before a reasonable activity trend can be computationally achieved.

6.
Polymers (Basel) ; 16(17)2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39274022

RESUMEN

Rare earth and transition metal ion-doped CaZnOS has garnered significant attention for its exceptional mechanoluminescence (ML) performance under mild mechanical stimuli and its capability for multicolor emissions. Since powdered phosphors are not directly usable, they require encapsulation within with polymers to create stable structures. This study investigates Mn2+-doped CaZnOS (CaZnOS:Mn2+) as the ML phosphor, optimizing its performance by varying the Mn2+ content, resulting in bright orange-red emissions from the d-d transitions of the Mn2+ activator. A quantum efficiency of 59.08% was achieved through the self-sensitization of the matrix lattice and energy transfer to the Mn2+ luminescent centers. The enhancement in ML due to Mn2+ doping is attributed to the reduced trap depth and increased trap concentration. Encapsulation with four polymers-PDMS, PU, SIL, and RTV-2-was explored to further optimize ML performance. Among these, PDMS provides the best ML output and sensitivity, owing to its slightly cross-linked structure and good triboelectric properties. The optimized CaZnOS:0.03Mn2+/PDMS composite, featuring excellent flexibility and recoverability, shows great potential for applications in anti-counterfeiting encryption, stress sensors, and wearable devices.

7.
Br J Pharmacol ; 181(5): 640-658, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37702564

RESUMEN

BACKGROUND AND PURPOSE: Atherosclerosis induced by cyclosporine A (CsA), an inhibitor of the calcineurin/nuclear factor of activated T cells (NFAT) pathway, is a major concern after organ transplantation. However, the atherosclerotic mechanisms of CsA remain obscure. We previously demonstrated that calcineurin/NFAT signalling inhibition contributes to atherogenesis via suppressing microRNA-204 (miR-204) transcription. We therefore hypothesised that miR-204 is involved in the development of CsA-induced atherosclerosis. EXPERIMENTAL APPROACH: ApoE-/- mice with macrophage-miR-204 overexpression were generated to determine the effects of miR-204 on CsA-induced atherosclerosis. Luciferase reporter assays and chromatin immunoprecipitation sequencing were performed to explore the targets mediating miR-204 effects. KEY RESULTS: CsA alone did not significantly affect atherosclerotic lesions or serum lipid levels. However, it exacerbated high-fat diet-induced atherosclerosis and hyperlipidemia in C57BL/6J and ApoE-/- mice, respectively. miR-204 levels decreased in circulating monocytes and plaque lesions during CsA-induced atherosclerosis. The upregulation of miR-204 in macrophages inhibited CsA-induced atherosclerotic plaque formation but did not affect serum lipid levels. miR-204 limited the CsA-induced foam cell formation by reducing the expression of the scavenger receptors SR-BII and CD36. SR-BII was post-transcriptionally regulated by mature miR-204-5p via 3'-UTR targeting. Additionally, nuclear-localised miR-204-3p prevented the CsA-induced binding of Ago2 to the CD36 promoter, suppressing CD36 transcription. SR-BII or CD36 expression restoration dampened the beneficial effects of miR-204 on CsA-induced atherosclerosis. CONCLUSION AND IMPLICATIONS: Macrophage miR-204 ameliorates CsA-induced atherosclerosis, suggesting that miR-204 may be a potential target for the prevention and treatment of CsA-related atherosclerotic side effects.


Asunto(s)
Aterosclerosis , MicroARNs , Placa Aterosclerótica , Animales , Ratones , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerosis/inducido químicamente , Aterosclerosis/genética , Calcineurina/metabolismo , Antígenos CD36/metabolismo , Ciclosporina/efectos adversos , Ciclosporina/metabolismo , Lípidos , Macrófagos , Ratones Endogámicos C57BL , MicroARNs/genética , MicroARNs/metabolismo , Placa Aterosclerótica/inducido químicamente , Placa Aterosclerótica/metabolismo
8.
Br J Dev Psychol ; 41(2): 140-156, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36577546

RESUMEN

To investigate the contributions of cognitive flexibility, inhibition and number label knowledge to children's numerical equivalence, one hundred and one 3- to 5-year-olds were administered the dimensional change card sorting task, the day-night task and the give-a-number task. The numerical equivalence was assessed with the numerical matching task in three surface similarity conditions. Results showed that, in the high surface similarity condition, cognitive flexibility and label knowledge, rather than inhibition, were significant predictors of children's performance in numerical equivalence. In the low surface similarity and the cross-mapping conditions, only cognitive flexibility, rather than number label knowledge and inhibition, significantly explained the unique variance in numerical equivalence. Besides, cognitive flexibility explained more variation in numerical equivalence in the cross-mapping condition compared with the low surface similarity condition. These findings highlight different roles of cognitive flexibility, inhibition and number label knowledge in numerical equivalence in the three surface similarity conditions.


Asunto(s)
Inhibición Psicológica , Conocimiento , Humanos , Preescolar , Cognición
9.
Polymers (Basel) ; 15(18)2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37765558

RESUMEN

Covalent organic frameworks (COFs) have gained considerable attention due to their highly conjugated π-skeletons, rendering them promising candidates for the design of light-emitting materials. In this study, we present two vinylene-linked COFs, namely, VL-COF-1 and VL-COF-2, which were synthesized through the Knoevenagel condensation of 2,4,6-trimethyl-1,3,5-triazine with terephthalaldehyde or 4,4'-biphenyldicarboxaldehyde. Both VL-COF-1 and VL-COF-2 exhibited excellent chemical and thermal stability. The presence of vinylene linkages between the constituent building blocks in these COFs resulted in broad excitation and emission properties. Remarkably, the designed VL-COFs demonstrated bright emission, fast fluorescence decay, and high stability, making them highly attractive for optoelectronic applications. To assess the potential of these VL-COFs in practical devices, we fabricated white-light-emitting diodes (WLEDs) coated with VL-COF-1 and VL-COF-2. Notably, the WLEDs coated with VL-COF-1 achieved high-quality white light emission, closely approximating standard white light. The promising performance of VL-COF-coated WLEDs suggests the feasibility of utilizing COF materials for stable and efficient lighting applications.

10.
Front Pharmacol ; 13: 1040999, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36457708

RESUMEN

Obesity-induced metabolic syndrome is a rapidly growing conundrum, reaching epidemic proportions globally. Chronic inflammation in obese adipose tissue plays a key role in metabolic syndrome with a series of local and systemic effects such as inflammatory cell infiltration and inflammatory cytokine secretion. Adipose tissue macrophages (ATM), as one of the main regulators in this process, are particularly crucial for pharmacological studies on obesity-related metabolic syndrome. Ponatinib, a multi-targeted tyrosine kinase inhibitor originally used to treat leukemia, has recently been found to improve dyslipidemia and atherosclerosis, suggesting that it may have profound effect on metabolic syndrome, although the mechanisms underlying have not yet been revealed. Here we discovered that ponatinib significantly improved insulin sensitivity in leptin deficient obese mice. In addition to that, ponatinib treatment remarkably ameliorated high fat diet-induced hyperlipidemia and inhibited ectopic lipid deposition in the liver. Interestingly, although ponatinib did not reduce but increase the weight of white adipose tissue (WAT), it remarkably suppressed the inflammatory response in WAT and preserved its function. Mechanistically, we showed that ponatinib had no direct effect on hepatocyte or adipocyte but attenuated free fatty acid (FFA) induced macrophage transformation from pro-inflammatory to anti-inflammatory phenotype. Moreover, adipocytes co-cultured with FFA-treated macrophages exhibited insulin resistance, while pre-treat these macrophages with ponatinib can ameliorate this process. These results suggested that the beneficial effects of ponatinib on metabolic disorders are achieved by inhibiting the inflammatory phenotypic transformation of ATMs, thereby maintaining the physiological function of adipose tissue under excessive obesity. The data here not only revealed the novel therapeutic function of ponatinib, but also provided a theoretical basis for the application of multi-target tyrosine kinase inhibitors in metabolic diseases.

11.
Medicine (Baltimore) ; 100(4): e24455, 2021 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-33530254

RESUMEN

RATIONALE: The clinical prognosis of peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) patients is poor. Therefore, effective treatment is still a challenge at present. Moreover, little is known about the value of radiotherapy in the treatment of PTCL-NOS. PATIENT CONCERNS: A 55-year-old male patient with eating difficulties and progressive exacerbation for 3 months was diagnosed as non-Hodgkin's lymphoma. Airway compression occurred after 2 cycles of first line treatment with cyclophosphamide-Adriamycin-vincristine-prednisone regimen, radiotherapy (48Gy/24f) was given as the second line therapy. DIAGNOSIS: After radiotherapy, the patient complained that mild intermittent dysphagia still existed. Endoscopic biopsy of the upper digestive tract confirmed necrotic material and superficial squamous epithelial mucosa, suggesting esophageal stricture after radiotherapy, which was indistinguishable from tumor residue. INTERVENTIONS: The patient received anti-inflammatory treatment outside the hospital and did not receive any other special treatment. OUTCOMES: The symptoms of dysphagia disappeared and the focus showed complete response (CR). As of October 1, 2020, the patient has been diagnosed with PTCL-NOS for more than 57 months and the overall survival (OS) have not been achieved. LESSONS: Radiotherapy has obvious and rapid anti-tumor effect on cyclophosphamide-Adriamycin-vincristine-prednisone refractory PTCL-NOS. At the same time, hollow organs after radiotherapy can lead to lumen stenosis and the symptoms of suspected recurrence which is difficult to distinguish only from the imaging findings.


Asunto(s)
Esófago/lesiones , Linfoma de Células T Periférico/terapia , Radioterapia/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Afasia/etiología , Ciclofosfamida/uso terapéutico , Doxorrubicina/uso terapéutico , Humanos , Linfoma de Células T Periférico/diagnóstico por imagen , Linfoma de Células T Periférico/tratamiento farmacológico , Linfoma de Células T Periférico/patología , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Tomografía de Emisión de Positrones , Prednisolona/uso terapéutico , Supervivencia sin Progresión , Vincristina/uso terapéutico
12.
Front Psychol ; 11: 756, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32477205

RESUMEN

This study aimed to examine the role of perceptual interference, semantic interference, and relational integration (RI) in the development of analogical reasoning, and to compare the interactive pattern of interference and RI in children and adults. In Experiment 1, we tested 31 3- and 4-year-olds, 27 5- and 6-year-olds, and 40 adults for perceptual interference and RI in analogical reasoning. Perceptual interference emerged when proper mapping between analogically matching objects was incoherent with their perceptual features. RI was evaluated via manipulation of the number of objects in an analogical scene. Significant main effects of perceptual interference and RI were found in children and adults. In Experiment 2, we tested 30 3- and 4-year-olds, 27 5- and 6-year-olds, and 40 adults for semantic interference and RI in analogical reasoning. Semantic interference emerged when proper mapping between analogically matching objects was incoherent with their categorical features. Results showed significant main effects of semantic interference and RI in children and adults. The results of both experiments suggested different mechanisms of interference and RI in children and adults. For children, interference and RI depended on shared cognitive sources. If one factor (i.e., interference resolution) needed more cognitive demand, there would be limited resources available for another factor (i.e., RI). Furthermore, for adults, the increased load of RI and interference on adults' analogical reasoning exceeded the sum of their respective singular effects. For 3- and 4-year-olds, the degree of perceptual interference was larger than the degree of semantic interference in the Binary Relation condition, whereas there was no significant difference between the degree of two types of interference in the Quaternary Relation condition. Moreover, for 5- and 6-year-olds, the degree of semantic interference was larger than the degree of perceptual interference in both relation conditions. For adults, there was no difference between the degree of two types of interference in both relation conditions. The article also discusses the theoretical and practical implications of this research.

13.
Aging (Albany NY) ; 12(13): 13502-13517, 2020 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-32644941

RESUMEN

In this study, we constructed a new survival model using mRNA expression-based stemness index (mRNAsi) for prognostic prediction in hepatocellular carcinoma (HCC). Weighted correlation network analysis (WGCNA) of HCC transcriptome data (374 HCC and 50 normal liver tissue samples) from the TCGA database revealed 7498 differentially expressed genes (DEGs) that clustered into seven gene modules. LASSO regression analysis of the top two gene modules identified ANGPT2, EMCN, GLDN, USHBP1 and ZNF532 as the top five mRNAsi-related genes. We constructed our survival model with these five genes and tested its performance using 243 HCC and 202 normal liver samples from the ICGC database. Kaplan-Meier survival curve and receive operating characteristic curve analyses showed that the survival model accurately predicted the prognosis and survival of high- and low-risk HCC patients with high sensitivity and specificity. The expression of these five genes was significantly higher in the HCC tissues from the TCGA, ICGC, and GEO datasets (GSE25097 and GSE14520) than in normal liver tissues. These findings demonstrate that a new survival model derived from five strongly correlating mRNAsi-related genes provides highly accurate prognoses for HCC patients.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/mortalidad , Neoplasias Hepáticas/mortalidad , Células Madre Neoplásicas/patología , Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Conjuntos de Datos como Asunto , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Estimación de Kaplan-Meier , Hígado , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Valor Predictivo de las Pruebas , Pronóstico , Mapas de Interacción de Proteínas/genética , ARN Mensajero/metabolismo , Curva ROC , Análisis de Regresión , Reproducibilidad de los Resultados , Medición de Riesgo/métodos
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