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1.
Small ; 20(12): e2308193, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37953460

RESUMEN

Designing catalysts to proceed with catalytic reactions along the desired reaction pathways, e.g., CO2 methanation, has received much attention but remains a huge challenge. This work reports one Ru1Ni single-atom alloy (SAA) catalyst (Ru1Ni/SiO2) prepared via a galvanic replacement reaction between RuCl3 and Ni nanoparticles (NPs) derived from the reduction of Ni phyllosilicate (Ni-ph). Ru1Ni/SiO2 achieved much improved selectivity toward hydrogenation of CO2 to CH4 and catalytic activity (Turnover frequency (TOF) value: 40.00 × 10-3 s-1), much higher than those of Ni/SiO2 (TOF value: 4.40 × 10-3 s-1) and most reported Ni-based catalysts (TOF value: 1.03 × 10-3-11.00 × 10-3 s-1). Experimental studies verify that Ru single atoms are anchored onto the Ni NPs surface via the Ru1-Ni coordination accompanied by electron transfer from Ru1 to Ni. Both in situ experiments and theoretical calculations confirm that the interface sites of Ru1Ni-SAA are the intrinsic active sites, which promote the direct dissociation of CO2 and lower the energy barrier for the hydrogenation of CO* intermediate, thereby directing and enhancing the CO2 hydrogenation to CH4.

2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(5): 1577-1585, 2022 Oct.
Artículo en Chino | MEDLINE | ID: mdl-36208269

RESUMEN

OBJECTIVE: To investigate the clinical outcomes and prognostic factors of refractory/relapsed acute myeloid leukemia (AML) patients who received allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: The clinical data of 80 refractory/relapsed AML patients who received allo-HSCT from December 2013 to June 2020 were retrospectively analyzed, including the overall survival (OS) rate, disease-free survival (DFS) rate, relapse rate, incidence of transplant-related mortality (TRM), and the related risk factors were explored. RESULTS: Hematopoietic reconstitution was obtained in all 80 patients after transplantation, the 3-year OS and DFS rates were (48.8±6.3)% and (40.8±6.7)%, respectively. The 3-year cumulative incidence of relapse and TRM were 33.8% (95%CI: 0.254-0.449) and 15.0%(95%CI: 0.114-0.198), respectively. Univariate analysis showed that non-remission (NR) status before transplantation, DNMT3A R882 mutations and grade II-IV acute graft-versus-host disease (aGVHD) had negative effects on OS and DFS. Multivariate analysis indicated that the DNMT3A R882 mutations and grade II-IV aGVHD were independent risk factors for OS (HR=0.253, 95%CI: 0.092-0.695, P=0.008; HR=5.681, 95%CI: 2.101-15.361, P=0.001) and DFS (HR=0.200, 95%CI: 0.071-0.569, P=0.003; HR=7.117, 95%CI: 2.556-19.818, P<0.001). The 3-year cumulative incidence of relapse was 71.4%(95%CI: 0.610-0.836) in genetic high-risk group, which was higher than 23.3%(95%CI: 0.147-0.370) in intermediate-risk group and 23.5%(95%CI: 0.127-0.437) in favorable-risk group (P=0.006). CONCLUSION: Allo-HSCT is an effective and safe choice for refractory/relapsed AML patients. DNMT3A R882 mutations and grade II-IV aGVHD are negative prognostic factors of allo-HSCT for refractory/relapsed AML patients.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Pronóstico , Recurrencia , Estudios Retrospectivos , Trasplante Homólogo/efectos adversos
3.
Bioresour Technol ; 137: 311-7, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23591118

RESUMEN

This work demonstrates the efficient hydrogenolysis of cellulose to C4-C7 alcohols and gas products (reaction 1) by coupling it with the reforming reaction of methanol (reaction 2) over bi-functional CuO-based catalysts. In this process, the CuO-based catalysts catalyze both the reactions 1 and 2, and the in situ regenerated H2 in the reaction 2 is used for the reaction 1. A series of CuO-MO/Al2O3 (M=Ce, Mg, Mn, Ni, Zn) catalysts were prepared by the co-precipitation method. Among these catalysts, CuO-ZnO/Al2O3 exhibited the highest activity to generate a high cellulose conversion of 88% and a high C4-C7 alcohols content above 95% in the liquid products. The CuO-ZnO/Al2O3 catalyst was stable under the reaction conditions and reusable after 4 runs. This work provides a cost-effective route to convert abundant renewable cellulose to liquid fuels.


Asunto(s)
Celulosa/metabolismo , Metanol/metabolismo , Biocombustibles , Catálisis , Celulosa/química , Cobre/química , Hidrógeno/química , Hidrógeno/metabolismo , Cinética , Metanol/química , Temperatura , Factores de Tiempo
4.
Cell Signal ; 25(6): 1438-46, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23499911

RESUMEN

Acute myeloid leukemia (AML) remains highly fatal, highlighting the need for improved understanding of signal pathways that can lead to the development of new therapeutic regimens targeting common molecular pathways shared across different AML subtypes. Here we demonstrate that astrocyte elevated gene-1 (AEG-1) is one of such pathways, involving in cell cycle and apoptosis regulation and contributing to enhanced proliferation and chemoresistance in HL-60 and U937 AML cells. The pleiotropic effects of AEG-1 on AML were found to correlate with two novel target genes, Aurora kinase A (AURKA) and Akt1. Down-regulation of AEG-1 by short-hairpin RNA (shRNA) could not only decrease AURKA expression both on mRNA and protein levels but also decrease the levels of pAkt473 and pAkt308 (the active forms of phosphorylated Akt), similar effect as using AURKA inhibitor Tozasertib (VX680). Furthermore, the AEG-1 shRNA-induced malignant phenotype changes could be mitigated by forced overexpression of AURKA through increased Akt1 activation and phosphorylation in AML cells. On the other hand, although exogenous expression of AEG-1 could increase both AURKA and Akt expression levels the simultaneous use of AURKA inhibitor Tozasertib blocked AEG-1's role of up-regulation of Akt expression in ECV304 cells, suggesting that AURKA might be a key mediator of AEG-1 in regulating Akt activation, and a key effector of AEG-1 in maintaining the malignant state of AML. Moreover, knockdown AEG-1 expression also changed the expression levels of PTEN, survivin and stathmin, the genes that have been reported to be involved in the development of several other malignant tumors. Our results provide evidence for AEG-1's carcinogenesis role in AML and reveal a novel functional link between AEG-1 and AURKA on Akt1 activation. AEG-1 can be an important candidate as a drug design target within AURKA signal pathway for more specific killing of AML cells while sparing normal cells.


Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Leucemia Mieloide Aguda/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Antineoplásicos/toxicidad , Aurora Quinasa A , Aurora Quinasas , Moléculas de Adhesión Celular/antagonistas & inhibidores , Moléculas de Adhesión Celular/genética , Supervivencia Celular/efectos de los fármacos , Centrosoma/metabolismo , Cisplatino/toxicidad , Regulación hacia Abajo/efectos de los fármacos , Células HL-60 , Humanos , Proteínas Inhibidoras de la Apoptosis/metabolismo , Leucemia Mieloide Aguda/patología , Proteínas de la Membrana , Fosfohidrolasa PTEN/metabolismo , Fenotipo , Fosforilación , Piperazinas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Interferencia de ARN , ARN Mensajero/metabolismo , ARN Interferente Pequeño/metabolismo , Proteínas de Unión al ARN , Estatmina/metabolismo , Survivin , Células U937 , Regulación hacia Arriba/efectos de los fármacos
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