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1.
Chemistry ; 26(18): 4013-4018, 2020 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-31482593

RESUMEN

Electroreduction of CO2 into formic acid (HCOOH) is of particular interest as a hydrogen carrier and chemical feedstock. However, its conversion is limited by a high overpotential and low stability due to undesirable catalysts and electrode design. Herein, an integrated 3D bismuth oxide ultrathin nanosheets/carbon foam electrode is designed by a sponge effect and N-atom anchor for energy-efficient and selective electrocatalytic conversion of CO2 to HCOOH for the first time. Benefitting from the unique 3D array foam architecture for highly efficient mass transfer, and optimized exposed active sites, as confirmed by density functional theory calculations, the integrated electrode achieves high electrocatalytic performance, including superior partial current density and faradaic efficiency (up to 94.1 %) at a moderate overpotential as well as a high energy conversion efficiency of 60.3 % and long-term durability.

2.
Angew Chem Int Ed Engl ; 58(28): 9464-9469, 2019 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-31090132

RESUMEN

The electrochemical N2 fixation, which is far from practical application in aqueous solution under ambient conditions, is extremely challenging and requires a rational design of electrocatalytic centers. We observed that bismuth (Bi) might be a promising candidate for this task because of its weak binding with H adatoms, which increases the selectivity and production rate. Furthermore, we successfully synthesized defect-rich Bi nanoplates as an efficient noble-metal-free N2 reduction electrocatalyst via a low-temperature plasma bombardment approach. When exclusively using 1 H NMR measurements with N2 gas as a quantitative testing method, the defect-rich Bi(110) nanoplates achieved a 15 NH3 production rate of 5.453 µg mgBi -1 h-1 and a Faradaic efficiency of 11.68 % at -0.6 V vs. RHE in aqueous solution at ambient conditions.

3.
Small ; 14(32): e1703843, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30003667

RESUMEN

Large-scale application of renewable energy and rapid development of electric vehicles have brought unprecedented demand for advanced energy-storage/conversion technologies and equipment. Rechargeable zinc (Zn)-air batteries represent one of the most promising candidates because of their high energy density, safety, environmental friendliness, and low cost. The air electrode plays a key role in managing the many complex physical and chemical processes occurring on it to achieve high performance of Zn-air batteries. Herein, recent advances of air electrodes from bifunctional catalysts to architectures are summarized, and their advantages and disadvantages are discussed to underline the importance of progress in the evolution of bifunctional air electrodes. Finally, some challenges and the direction of future research are provided for the optimized design of bifunctional air electrodes to achieve high performance of rechargeable Zn-air batteries.

4.
Breast ; 49: 233-241, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31918322

RESUMEN

PURPOSE: To investigate the effect of 21-gene recurrence score (RS) on chemotherapy-decision making and prognosis in breast cancer patients aged <40 years. METHODS: Using the Surveillance, Epidemiology, and End Results program, we included patients aged <40 years with tumor size ≤5 cm, node negative, and estrogen receptor-positive breast cancer between 2004 and 2015. Correlations among the 21-gene RS, chemotherapy decision-making and prognosis were analyzed. RESULTS: We included 2721 patients in this study. According to TAILORx cutoffs, 352 (12.9%), 1814 (66.7%), and 555 (20.4%) patients were classified as low-, intermediate-, and high-risk cohorts, respectively. The 21-gene RS categories were associated with the probability of receiving chemotherapy, with 7.1%, 33.4%, and 77.1% of patients in low-, intermediate-, and high-risk cohorts treated with chemotherapy, respectively (P < 0.001). Those in the intermediate-risk cohort were significantly less likely to receive chemotherapy over time (P = 0.008), and the trends of chemotherapy receipt were stable in the low-risk and high-risk cohorts over time. Multivariate analysis showed that the 21-gene RS was an independent prognostic indicator for breast cancer specific survival. In the stratified analysis, the receipt of chemotherapy was associated with better breast cancer specific survival in the high-risk cohort (P = 0.028), but not in the intermediate-risk cohort (P = 0.223). CONCLUSIONS: 21-gene RS has clinical implications for young breast cancer patients with respect to optimizing chemotherapy-decisions. Despite increasing rates of chemotherapy receipt in young patients, more studies are needed to determine the definitive effect of chemotherapy in young patients with three RS categories.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/genética , Reglas de Decisión Clínica , Toma de Decisiones Clínicas/métodos , Pruebas Genéticas/métodos , Recurrencia Local de Neoplasia/genética , Adulto , Factores de Edad , Biomarcadores de Tumor/genética , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/mortalidad , Carcinoma Lobular/diagnóstico , Carcinoma Lobular/tratamiento farmacológico , Carcinoma Lobular/genética , Carcinoma Lobular/mortalidad , Femenino , Estudios de Seguimiento , Perfilación de la Expresión Génica , Humanos , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/prevención & control , Pronóstico , Estudios Retrospectivos , Medición de Riesgo , Programa de VERF , Análisis de Supervivencia
5.
World J Gastroenterol ; 14(25): 4070-6, 2008 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-18609693

RESUMEN

AIM: To investigate the microsatellite alterations in phenotypically normal esophageal squamous epithelium and metaplasia-dysplasia-adenocarcinoma sequence. METHODS: Forty-one specimens were obtained from esophageal cancer (EC) patients. Histopathological assessment identified 23 squamous cell carcinomas (SCC) and 18 adenocarcinomas (ADC), including only 8 ADC with Barrett esophageal columnar epithelium (metaplasia) and dysplasia adjacent to ADC. Paraffin-embedded normal squamous epithelium, Barrett esophageal columnar epithelium (metaplasia), dysplasia and esophageal tumor tissues were dissected from the surrounding tissues under microscopic guidance. DNA was extracted using proteinase K digestion buffer, and DNA was diluted at 1:100, 1:1000, 1:5000, 1:10000 and 1:50000, respectively. Seven microsatellite markers (D2S123, D3S1616, D3S1300, D5S346, D17S787, D18S58 and BATRII loci) were used in this study. Un-dilution and dilution polymerase chain reactions (PCR) were performed, and microsatellite analysis was carried out. RESULTS: No statistically significant difference was found in microsatellite instability (MSI) and loss of heterozygosity (LOH) of un-diluted DNA between SCC and ADC. The levels of MSI and LOH were high in the metaplasia-dysplasia-adenocarcinoma sequence of diluted DNA. The more the diluted DNA was, the higher the rates of MSI and LOH were at the above 7 loci, especially at D3S1616, D5S346, D2S123, D3S1300 and D18S58 loci. CONCLUSION: The sequence of metaplasia-dysplasia-adenocarcinoma is associated with microsatellite alterations, including MSI and LOH. The MSI and LOH may be the early genetic events during esophageal carcinogenesis, and genetic alterations at the D3S1616, D5S346 and D3S123 loci may play a role in the progress of microsatellite alterations.


Asunto(s)
Adenocarcinoma/genética , Esófago de Barrett/genética , Carcinoma de Células Escamosas/genética , Transformación Celular Neoplásica/genética , Neoplasias Esofágicas/genética , Esófago/patología , Regulación Neoplásica de la Expresión Génica , Inestabilidad de Microsatélites , Lesiones Precancerosas/genética , Adenocarcinoma/patología , Esófago de Barrett/patología , Carcinoma de Células Escamosas/patología , Transformación Celular Neoplásica/patología , Neoplasias Esofágicas/patología , Marcadores Genéticos , Genotipo , Humanos , Pérdida de Heterocigocidad , Metaplasia , Adhesión en Parafina , Fenotipo , Reacción en Cadena de la Polimerasa , Lesiones Precancerosas/patología
6.
Adv Mater ; 30(14): e1706194, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29473227

RESUMEN

Conversion of carbon dioxide (CO2 ) into valuable chemicals, especially liquid fuels, through electrochemical reduction driven by sustainable energy sources, is a promising way to get rid of dependence on fossil fuels, wherein developing of highly efficient catalyst is still of paramount importance. In this study, as a proof-of-concept experiment, first a facile while very effective protocol is proposed to synthesize amorphous Cu NPs. Unexpectedly, superior electrochemical performances, including high catalytic activity and selectivity of CO2 reduction to liquid fuels are achieved, that is, a total Faradaic efficiency of liquid fuels can sum up to the maximum value of 59% at -1.4 V, with formic acid (HCOOH) and ethanol (C2 H6 O) account for 37% and 22%, respectively, as well as a desirable long-term stability even up to 12 h. More importantly, this work opens a new avenue for improved electroreduction of CO2 based on amorphous metal catalysts.

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