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1.
Inorg Chem ; 63(34): 16103-16113, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39149799

RESUMO

The construction of doped molecular clusters is an intriguing way to perform bimetallic doping for electrocatalysts. However, efficiently harnessing the benefits of a doping strategy and alloy engineering to create a nanostructure for electrocatalytic application at the molecular level has consistently posed a challenge. Here we propose an in situ reconstruction strategy aimed at producing an alloy nanostructure through a pyrolysis process, originating from bowknot-like heterometallic clusters. The Schiff base, denoted as ligand L1 (o-vanillin ethylenediamine), was introduced as a precursor to coordinate Fe and Co metals, thereby yielding a heteronuclear metal cluster [(FeCo)(L1)2O]CH3CN. Subsequently, a comprehensive investigation of the in situ reconstruction process [(FeCo)(L1)2O](CH3CN) → [(FeCo)(L1)2O] → [M-O-M/M-O] [CH3+/CH3O+/H2C═N/C2H5+/C4H4+] → [FeCo/Fe3O4/Fe2O3/Co3O4][carbon layer] led to the formation of MOx/CoFe@NC-700 during the pyrolysis. This process reveals that the metals Fe and Co in the clusters undergo partly in situ evolution into FeCo alloys, resulting in the successful preparation of MOx/CoFe@NC (M = Fe, Co) nanomaterials that leverage the advantages of both doping strategies and alloy engineering. The synergistic interaction between alloy particles and metal oxides establishes active sites that contribute to the excellent oxygen evolution (OER) and hydrogen evolution (HER) catalytic behaviors. Notably, these materials exhibit outstanding OER and HER properties under alkaline conditions, with overpotentials of 191 and 88 mV for OER and HER, respectively, at 10 mA cm-2. Investigation of the in situ conversion of Schiff base bimetal clusters into alloy materials through pyrolysis offers a novel strategy for advancing electrocatalytic applications.

2.
Mol Pharm ; 18(3): 1277-1284, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33492962

RESUMO

Glycogen synthase kinase-3ß (GSK-3ß), a cytoplasmic serine/threonine protein kinase, is involved in several human pathologies including Alzheimer's disease, bipolar disorder, diabetes, and cancer. Positron emission tomography (PET) imaging of GSK-3ß could aid in investigating GSK-3ß levels under normal and pathological conditions. In this study, we designed and synthesized fluorinated PET radioligands starting with recently identified isonicotinamide derivatives that showed potent affinity to GSK-3ß. After extensive in vitro inhibitory activity assays and analyzing U87 cell uptake, we identified [18F]10a-d as potential tracers with good specificity and high affinity. They were then subjected to further in vivo evaluation in rodent brain comprising PET imaging and metabolism studies. The radioligands [18F]10b-d penetrated the blood-brain barrier and accumulated in GSK-3ß-rich regions, including amygdala, cerebellum, and hippocampus. Also, it could be specifically blocked using the corresponding standard compounds. With these results, this work sets the basis for further development of novel 18F-labeled GSK-3ß PET probes.


Assuntos
Radioisótopos de Flúor/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Niacinamida/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Animais , Transtorno Bipolar/diagnóstico por imagem , Transtorno Bipolar/metabolismo , Barreira Hematoencefálica/diagnóstico por imagem , Barreira Hematoencefálica/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Linhagem Celular Tumoral , Diabetes Mellitus/diagnóstico por imagem , Diabetes Mellitus/metabolismo , Humanos , Ligantes , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Ratos
3.
Nucl Med Commun ; 41(5): 477-484, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32168265

RESUMO

OBJECTIVE: The study is to investigate the application of F-fluorodeoxyglucose (F-FDG) PET/computerized tomography (CT) for the evaluation of mantle cell lymphoma (MCL). METHODS: We retrospectively analyzed 39 patients who were pathologically diagnosed with MCL and underwent F-FDG PET/CT before treatment between August 2007 and August 2018. We compared the clinical information and PET/CT imaging characteristics in different groups based on bone marrow invasion, spleen invasion or International Prognostic Index (IPI) score. We also assessed the efficacy of PET/CT evaluation basing on the follow-up PET CT findings of 21 MCL patients and their biopsies. RESULTS: Thirty-five patients were stage IV according to the Revised Ann Arbor Staging System. Lymph node involvement was observed in all 39 cases. The maximum diameter of the affected lymph nodes (4.33 ± 3.09 cm) and maximum standardized uptake value (SUVmax) (8.38 ± 4.99) was positively correlated (r = 0.486, P = 0.002). Extranodal invasion was identified in 38 patients with MCL, and the SUVmax of extranodal invasion was 7.34 ± 3.31. Extranodal invasion was most common in the spleen (25/38) and bone marrow (18/38). The group with bone marrow invasion was more prone to nasopharyngeal, lung and renal invasions (all P < 0.05). The groups with bone marrow invasion or spleen invasion were more likely to have decreased hemoglobin (Hgb) and platelets (all P < 0.01). The IPI high-risk group was more prone to lung involvement, elevated LDH and CRP, and decreased Hgb (all P < 0.05). Among the follow-up of 30 MCL patients, the 2-year progression-free survival and overall survival rates were 73.33 and 87.50%, respectively. PET/CT reexaminations of 21 MCL patients after treatment showed that the sensitivity, specificity, negative predictive value, positive predictive value and accuracy of the efficacy evaluation were 80, 90.91, 88.89, 83.33 and 85.71%, respectively. CONCLUSION: F-FDG PET/CT imaging has important application value in the diagnosis, staging, treatment efficacy assessment and prognosis monitoring of MCL, especially in the systemic assessment of advanced MCL.


Assuntos
Fluordesoxiglucose F18 , Linfoma de Célula do Manto/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto , Idoso de 80 Anos ou mais , Humanos , Linfoma de Célula do Manto/patologia , Linfoma de Célula do Manto/terapia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos
4.
J Environ Sci (China) ; 17(4): 623-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16158592

RESUMO

The pretreatment technology of wet air oxidation (WAO) and coagulation and acidic hydrolysis for apramycin wastewater was investigated in this paper. The COD, apramycin, NH4+ concentration, and the ratio of BOD5/COD were analyzed, and the color and odor of the effluent were observed. WAO of apramycin wastewater, without catalyst and with RuO2/Al2O3 and RuO2-CeO2/Al2O3 catalysts, was carried out at degradation temperature of 200 degrees C and the total pressure of 4 MPa in a 1 L batch reactor. The result showed that the apramycin removals were respectively 50.2% and 55.0%, COD removals were 40.0% and 46.0%, and the ratio of BOD5/COD was increased to 0.49 and 0.54 with RuO2/Al2O3 and RuO2-CeO2/Al2O3 catalysts in catylytic wet air oxidation (CWAO) after the reaction of 150 min. With the pretreatment of coagulation and acidic hydrolysis, COD and apramycin removals were slight decreased, and the ratio of BOD5/COD was increased to 0.45, and the effluents was not suitable to biological treatment. The color and odor of the wastewater were effectively controlled and the reaction time was obviously shortened with WAO. HO2 may promote organic compounds oxidized in WAO of the apramycin wastewater. The addition of CeO2 could promote the activity and stability of RuO2/Al2O3 in WAO of apramycin wastewater.


Assuntos
Ar , Resíduos Industriais , Nebramicina/análogos & derivados , Poluentes Químicos da Água , Biodegradação Ambiental , Catálise , Indústria Farmacêutica , Nebramicina/química , Oxirredução
5.
Huan Jing Ke Xue ; 29(9): 2522-8, 2008 Sep.
Artigo em Zh | MEDLINE | ID: mdl-19068637

RESUMO

Multi-walled carbon nanotubes (MWNTs) without any metal ions were used as the catalyst, and investigated in the CWAO of phenol and aniline in a batch reactor. The structures of the MWNTs were characterized by means of SEM and TEM. It showed that the MWNTs, treated with the mixed acid (HNO3-H2SO4), displayed excellent activity and stability in the CWAO. Under the reaction temperature of 160 degrees C, the total pressure of 2.5 MPa, the initial concentration of 1000 mg/L and loading the catalyst of 1.6 g/L, 100% phenol and 86% COD were removed after 120 min reaction in CWAO of phenol. At the same operating conditions, 83% aniline and 68% COD removals were obtained in the CWAO of aniline solution when the initial concentration of aniline was 2 000 mg/L. The surface functional groups played the important role for the high activity of the MWNTs in CWAO of organic compounds.


Assuntos
Compostos de Anilina/química , Carbono/química , Nanotubos/química , Fenol/química , Eliminação de Resíduos Líquidos/métodos , Reatores Biológicos , Catálise , Oxirredução
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