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1.
Opt Lett ; 49(15): 4134-4137, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090877

RESUMEN

Ruddlesden-Popper (RP) perovskites promise next-generation gain media for laser devices. However, most RP perovskite lasers are still suffering from inferior performance characteristics, such as inadequate energy transfer, unstable emission, and short lifetime. To address the above problems, high crystalline quality, compact, and smooth PEA2FA2Pb3Br10 films with uniform phase distribution were successfully prepared by ionic liquid (IL) methylammonium acetate (MAAc) in an air environment. Compared with the PEA2FA2Pb3Br10 film prepared by the traditional solvent dimethyl sulfoxide (DMSO), an enhanced amplified spontaneous emission (ASE) with a lower threshold of 58 µJ·cm-2 from the MAAc-treated film was obtained under nanosecond laser excitation. The transient absorption (TA) spectroscopy revealed that a uniform phase distribution and more efficient energy transfer processes were achieved in the PEA2FA2Pb3Br10-MAAc film, leading to an enhanced band-to-band spontaneous emission process. Furthermore, the films exhibited better stability, showing no signs of degradation under the 120 min pulsed laser pumping in air and stability of ASE spectra at even 95% humidity conditions. This study provides an important foundation for achieving high-performance optically pumped lasers based on the unique RP perovskites.

2.
EClinicalMedicine ; 73: 102685, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39022796

RESUMEN

Background: Rosai-Dorfman disease (RDD) is a rare heterogeneous histiocytic disorder lacking standardized first-line treatment. Methods: This single-center, phase 2 prospective study enrolled 13 newly diagnosed and 10 recurrent RDD patients from June 2021 to March 2023 at Peking Union Medical College Hospital (Beijing, China). Lenalidomide 25 mg days 1-21 plus dexamethasone 40 mg days 1, 8, 15, 22 was administered in 28-day cycles, totaling 12 cycles. The primary endpoint was progression-free survival (PFS). Secondary endpoints were overall response rate (ORR) to lenalidomide and dexamethasone (RD) regimen, toxicity, and overall survival (OS) measured from RD start to death or last follow-up. OS and PFS were estimated according to Kaplan-Meier survival analysis and compared with the log-rank test. For OS and OR rate, 95% confidence limits were obtained using the Clopper-Pearson method, with standard methods used for PFS. p < 0.05 was considered statistically significant. The trial was registered with ClinicalTrials.gov (NCT04924647). Findings: The median age was 44 years (IQR 35-54). All patients had extranodal RDD. MAPK pathway alterations occurred in 6/18 (33%). Elevated IL-6 and TNF-α were found in 39% (n = 9) and 70% (n = 16), respectively. All patients received ≥6 cycles (median 12, range 6-12, IQR 10-12). The ORR was 87% (20/23, 95% CI 66%-97%), 30% (n = 7) complete remission, 57% (n = 13) partial remission). Treatment with RD significantly decreased median serum levels of both IL-6 (from 5.9 (IQR 4.2-8.7) to 2.9 (IQR 2.1-5.9) pg/mL, p = 0.031) and TNF-α (from 12.2 (IQR 8.6-17.9) to 8.3 (IQR 6.1-10.5) pg/mL, p = 0.0012). With a median 26 months follow-up (range 6-28, IQR 16-28), 4 patients relapsed and none died. Two-year OS and PFS were 100.0% (95% CI 85%-100%) and 69.0% (95% CI 51%-94%), respectively. No grade 3-4 adverse events or discontinuations due to adverse events occurred. Twelve patients (n = 12, 52%) had grade 1-2 hematological toxicity. Other toxicities included constipation (n = 2, 9%), glucose intolerance (n = 2, 9%), edema (n = 2, 9%), insomnia (n = 1, 4%), and tremor (n = 1, 4%). Interpretation: Lenalidomide and dexamethasone regimen is an effective and safe regimen for newly diagnosed and recurrent RDD. Funding: National Natural Science Foundation of China, Beijing Natural Science Haidian frontier Foundation Funding, and the National High Level Hospital Clinical Research Funding.

3.
Inorg Chem ; 63(28): 12803-12809, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38957131

RESUMEN

A high-nuclear Co-added polyoxometalate (CoAP) was synthesized via a hydrothermal reaction: H14.5K9Na7.5-{[Co8(µ2-OH)(µ3-OH)2(H2O)2(Co(H2O)GeW6O26)(B-α-GeW9O34)2][BO(OH)2][Co12(µ2-OH)(µ3-OH)5(H2O)3(Co(H2O)GeW6O26)(GeW6O26)(B-α-GeW9O34)]}·46H2O (1). The polyoxoanion of 1 contains a large Co20 cluster gathered by lacunary GeW6O26 and GeW9O34 subunits. 1 represents a one-dimensional (1D) chain formed by adjacent polyoxoanions coupling through a CoO6 double bridge, showing the first example of a high-nuclear CoAP-based inorganic chain. 1 served as an efficient electrocatalyst in oxygen evolution reactions (OERs).

4.
J Am Chem Soc ; 146(20): 14260-14266, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38714344

RESUMEN

The electrochemical CO2 reduction reaction by copper-based catalysts features a promising approach to generate value-added multicarbon (C2+) products. However, due to the unfavored formation of oxygenate intermediates on the catalyst surface, the selectivity of C2+ alcohols like ethanol remains unsatisfactory compared to that of ethylene. The bifurcation point (i.e., the CH2═CHO* intermediate adsorbed on Cu via a Cu-O-C linkage) is critical to the C2+ product selectivity, whereas the subsequent cleavage of the Cu-O or the O-C bond determines the ethanol or ethylene pathway. Inspired by the hard-soft acid-base theory, in this work, we demonstrate an electron delocalization tuning strategy of the Cu catalyst by a nitrene surface functionalization approach, which allows weakening and cleaving of the Cu-O bond of the adsorbed CH2═CHO*, as well as accelerating hydrogenation of the C═C bond along the ethanol pathway. As a result, the nitrene-functionalized Cu catalyst exhibited a much-enhanced ethanol Faradaic efficiency of 45% with a peak partial current density of 406 mA·cm-2, substantially exceeding that of unmodified Cu or amide-functionalized Cu. When assembled in a membrane electrode assembly electrolyzer, the catalyst presented a stable CO2-to-ethanol conversion for >300 h at an industrial current density of 400 mA·cm-2.

5.
Heart ; 110(13): 899-907, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38772574

RESUMEN

OBJECTIVE: To evaluate the heart response of Erdheim-Chester disease (ECD) through continuous follow-up within our large cohort, for which there is a lack of understanding. METHODS: We conducted a retrospective analysis of clinical data from patients with ECD with cardiac involvement diagnosed at our centre between January 2010 and August 2023. We assessed the heart response by integrating pericardial effusion and metabolic responses. RESULTS: A total of 40 patients were included, with a median age of 51.5 years (range: 29-66) and a BRAFV600E mutation rate of 56%. The most common imaging manifestations observed were pericardial effusion (73%), right atrium (70%) and right atrioventricular sulcus infiltration (58%). Among 21 evaluable patients, 18 (86%) achieved a heart response including 5 (24%) complete response (CR) and 13 (62%) partial response (PR). The CR rate of pericardial effusion response was 33%, while the PR rate was 56%. Regarding the cardiac mass response, 33% of patients showed PR. For cardiac metabolic response, 32% and 53% of patients achieved complete and partial metabolic response, respectively. There was a correlation between pericardial effusion response and cardiac metabolic response (r=0.73 (95% CI 0.12 to 0.83), p<0.001). The median follow-up was 50.2 months (range: 1.0-102.8 months). The estimated 5-year overall survival was 78.9%. The median progression-free survival was 59.4 months (95% CI 26.2 to 92.7 months). Patients who received BRAF inhibitors achieved better heart response (p=0.037) regardless of treatment lines. CONCLUSION: We pioneered the evaluation of heart response of ECD considering both pericardial effusion and cardiac metabolic response within our cohort, revealing a correlation between these two indicators. BRAF inhibitors may improve heart response, regardless of the treatment lines.


Asunto(s)
Enfermedad de Erdheim-Chester , Derrame Pericárdico , Humanos , Enfermedad de Erdheim-Chester/complicaciones , Enfermedad de Erdheim-Chester/tratamiento farmacológico , Enfermedad de Erdheim-Chester/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Adulto , Estudios Retrospectivos , Anciano , Derrame Pericárdico/etiología , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Resultado del Tratamiento , Mutación
6.
Nano Lett ; 24(23): 7004-7011, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38804892

RESUMEN

Perovskite nanoplatelets (NPLs) show great potential for high-color-purity light-emitting diodes (LEDs) due to their narrow line width and high exciton binding energy. However, the performance of perovskite NPL LEDs lags far behind perovskite quantum dot-/film-based LEDs, owing to their material instability and poor carrier transport. Here, we achieved efficient and stable pure blue-emitting CsPbBr3 NPLs with outstanding optical and electrical properties by using an aromatic ligand, 4-bromothiophene-2-carboxaldehyde (BTC). The BTC ligands with thiophene groups can guide two-dimensional growth and inhibit out-of-plane ripening of CsPbBr3 NPLs, which, meanwhile, increases their structural stability via strongly interacting with PbBr64- octahedra. Moreover, aromatic structures with delocalized π-bonds facilitate charge transport, diminish band tail states, and suppress Auger processes in CsPbBr3 NPLs. Consequently, the LEDs demonstrate efficient and color-stable blue emissions at 465 nm with a narrow emission line width of 17 nm and a maximum external quantum efficiency (EQE) of 5.4%, representing the state-of-the-art CsPbBr3 NPL LEDs.

7.
Environ Sci Technol ; 58(23): 10287-10297, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38805641

RESUMEN

Though long recognized as synthetic precursors to other poly- and perfluoroalkyl substances (PFASs), most poly- and perfluoroalkyl sulfonyl halides (PASXs) cannot be directly measured and have generally received minimal attention. Inspired by the redox reaction between sulfonyl halide groups and p-toluenethiol in organic chemistry, we developed a novel nontarget analysis strategy for PASXs by intergrating derivatization and specific fragment-based liquid chromatography-high resolution mass spectrometry screening for m/z 82.961 [SO2F-] and m/z 95.934 [S2O2-]. By using this strategy, we discovered 11 PASXs, namely, perfluoroalkyl sulfonyl fluorides (5), polyfluoroalkyl sulfonyl fluorides (2), unsaturated perfluoroalkyl sulfonyl fluoride (1), and perfluoroalkyl sulfonyl chlorides (3) in soil samples collected from an abandoned fluorochemical manufacturing park. These average ∑PASXs concentrations were 1120 µg kg-1 (range: 9.7-9860 µg kg-1), which were very likely to be the key intermediates and undesired byproducts of electrochemical fluorination processes. Spatial variation in the mass ratio of ∑PASXs to ∑PFSAs (range: 0.7-795%) also indicates their different transportation pathways. More importantly, the decline of PASXs and increase of perfluoroalkyl sulfonates (when compared to a prior study at this site) suggest the continued hydrolysis of PASXs and the relatively fast environmental transformation rates in the abandoned fluorochemical park soils. Overall, these findings demonstrated the utility of a novel nontarget analysis strategy, which may change most PASXs from inferred precursors to measured intermediates and further could be adapted for structures, distribution, and transformation studies of PFASXs in other matrices.


Asunto(s)
Espectrometría de Masas , Contaminantes del Suelo , Suelo , Cromatografía Liquida , Contaminantes del Suelo/química , Suelo/química , Fluorocarburos/química , Monitoreo del Ambiente/métodos
8.
Acta Biochim Biophys Sin (Shanghai) ; 56(2): 174-183, 2024 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273784

RESUMEN

The most frequent primary brain tumor in adults is glioma, yet no effective curative treatments are currently available. Our previous study demonstrated the enhancing effects of JARID2 on glioma sensitivity to TMZ treatment. In this study, miR-155 is predicted to target JARID2. miR-155 is overexpressed in clinical glioma specimens and cell lines. miR-155 overexpression in glioma cells enhances cell viability and represses cell apoptosis. Through targeting, miR-155 inhibits JARID2 expression. miR-155 inhibition inhibits glioma cell viability and enhances cell apoptosis, whereas JARID2 knockdown enhances cell viability and inhibits cell apoptosis; JARID2 knockdown partially reverses miR-155 inhibition effects on glioma phenotypes. miR-155 inhibition reduces but knockdown of JARID2 promotes the tumor formation ability of glioma cells in vivo. Valproic acid (VPA) upregulates JARID2 expression, inhibits glioma cell viability and enhances cell apoptosis. VPA downregulates the expression level of miR-155 by increasing the methylation level of the miR-155 promoter, suggesting that the miR-155/JARID2 axis is implicated in VPA inhibition of glioma cell viability and enhancement of glioma cell apoptosis. This study demonstrates a new mechanism of VPA treatment of gliomas by affecting the miR-155/JARID2 axis, which could be regarded as a new strategy for the prevention and treatment of glioma.


Asunto(s)
Neoplasias Encefálicas , Glioma , MicroARNs , Humanos , Ácido Valproico/farmacología , Línea Celular Tumoral , Glioma/tratamiento farmacológico , Glioma/genética , Glioma/metabolismo , MicroARNs/metabolismo , Metilación , Proliferación Celular/genética , Apoptosis/genética , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Regulación Neoplásica de la Expresión Génica
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