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1.
J Am Chem Soc ; 146(29): 19998-20008, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38865282

RESUMO

As the dimensionality of materials generally affects their characteristics, thin films composed of low-dimensional nanomaterials, such as nanowires (NWs) or nanoplates, are of great importance in modern engineering. Among various bottom-up film fabrication strategies, interfacial assembly of nanoscale building blocks holds great promise in constructing large-scale aligned thin films, leading to emergent or enhanced collective properties compared to individual building blocks. As for 1D nanostructures, the interfacial self-assembly causes the morphology orientation, effectively achieving anisotropic electrical, thermal, and optical conduction. However, issues such as defects between each nanoscale building block, crystal orientation, and homogeneity constrain the application of ordered films. The precise control of transdimensional synthesis and the formation mechanism from 1D to 2D are rarely reported. To meet this gap, we introduce an interfacial-assembly-induced interfacial synthesis strategy and successfully synthesize quasi-2D nanofilms via the oriented attachment of 1D NWs on the liquid interface. Theoretical sampling and simulation show that NWs on the liquid interface maintain their lowest interaction energy for the ordered crystal plane (110) orientation and then rearrange and attach to the quasi-2D nanofilm. This quasi-2D nanofilm shows enhanced electric conductivity and unique optical properties compared with its corresponding 1D geometry materials. Uncovering these growth pathways of the 1D-to-2D transition provides opportunities for future material design and synthesis at the interface.

2.
Nat Commun ; 15(1): 3208, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615045

RESUMO

Investigations of one-dimensional segmented heteronanostructures (1D-SHs) have recently attracted much attention due to their potentials for applications resulting from their structure and synergistic effects between compositions and interfaces. Unfortunately, developing a simple, versatile and controlled synthetic method to fabricate 1D-SHs is still a challenge. Here we demonstrate a stress-induced axial ordering mechanism to describe the synthesis of 1D-SHs by a general under-stoichiometric reaction strategy. Using the continuum phase-field simulations, we elaborate a three-stage evolution process of the regular segment alternations. This strategy, accompanied by easy chemical post-transformations, enables to synthesize 25 1D-SHs, including 17 nanowire-nanowire and 8 nanowire-nanotube nanostructures with 13 elements (Ag, Te, Cu, Pt, Pb, Cd, Sb, Se, Bi, Rh, Ir, Ru, Zn) involved. This ordering evolution-driven synthesis will help to investigate the ordering reconstruction and potential applications of 1D-SHs.

3.
Huan Jing Ke Xue ; 43(4): 2124-2132, 2022 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-35393836

RESUMO

Exploring the spatial distribution characteristics and variation law of soil pH and analyzing the impact of environmental factors on the spatial differentiation of soil pH are of great significance to the accurate management of soil pH and the sustainable utilization of soil resources in the complex mountainous environment of Anshun City. Based on 22 851 field sampling points, using the methods of global Moran's I index, cold and hot spot analysis, semi-variance function, and Kriging interpolation, the spatial structure characteristics and distribution law of soil pH in Anshun City were revealed from different angles, and the influence of environmental factors on its spatial differentiation was analyzed with the help of geographic detectors. The results showed that:① the variation range of topsoil pH value in Anshun City was 3.56-8.61, the mean value was 6.28, and the coefficient of variation was 16.33%. ② In the global space, soil pH showed aggregation distribution; in the local space, the west and northwest were hot spots, whereas the east and south were cold spots. The nugget coefficient (40.19%) showed that the spatial variability in soil pH was determined by both structural and random factors, but the role of structural factors was greater. ③ In terms of spatial distribution, soil pH mainly presented a patchy mosaic distribution pattern, in which slightly acidic soil (57.14%) was concentrated in the east, northeast, and south of Anshun City; neutral soil (30.13%) was concentrated in the west, northwest, and southeast; and strongly acidic soil (6.12%) and alkaline soil (6.45%) were embedded in slightly acidic soil and neutral soil, respectively, in a block structure. ④ The geo-detector analysis showed that the explanatory power of various environmental factors to the spatial variation in soil pH was ranked as soil type (9.4%)>soil forming parent rock (7.9%)>altitude (2.1%)>land use (1.8%)>slope (0.1%), in which the q value of the interaction between soil type and parent rock type and other factors was large. Therefore, soil type and parent rock type were the main controlling factors of soil pH spatial variation in Anshun City.


Assuntos
Solo , China , Cidades , Concentração de Íons de Hidrogênio , Solo/química , Análise Espacial
4.
J Am Chem Soc ; 143(32): 12600-12608, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34288654

RESUMO

The kinetics of electrode reactions including mass transfer and surface reaction is essential in electrocatalysis, as it strongly determines the apparent reaction rates, especially on nanostructured electrocatalysts. However, important challenges still remain in optimizing the kinetics of given catalysts with suitable constituents, morphology, and crystalline design to maximize the electrocatalytic performances. We propose a comprehensive kinetic model coupling mass transfer and surface reaction on the nanocatalyst-modified electrode surface to explore and shed light on the kinetic optimization in electrocatalysis. Moreover, a theory-guided microchemical engineering (MCE) strategy has been demonstrated to rationally redesign the catalysts with optimized kinetics. Experimental measurements for methanol oxidation reaction in a 3D ordered channel with tunable channel sizes confirm the calculation prediction. Under the optimized channel size, mass transfer and surface reaction in the channeled microreactor are both well regulated. This MCE strategy will bring about a significant leap forward in structured catalyst design and kinetic modulation.

5.
Front Oncol ; 10: 1753, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33102205

RESUMO

Purpose: Triple-negative breast cancer (TNBC) is a subtype with distinct heterogeneity, high invasiveness, and poorer prognosis. There is a controversy about adjuvant chemotherapy (ACT) at the T1aN0M0 stage. This study was carried out to assess the survival benefit of ACT for these patients. Methods: We identified 1,099 patients with T1aN0M0 TNBC who were diagnosed between 2010 and 2016 from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariable analyses were conducted to determine factors related to survival. One-to-one (1:1) propensity score matching (PSM) was applied to construct a matched sample consisting of pairs of ACT and non-ACT subjects. Breast cancer-specific survival (BCSS) and overall survival (OS) of the two groups were evaluated by Kaplan-Meier plots and Cox proportional hazard regression models. Stratified analysis according to different variables was also performed. Results: No obvious differences in demographic or clinical characteristics were found between patients who had ACT and those without ACT therapy in terms of race, marital status, laterality, or radiation therapy. A higher proportion of patients who were older, had a higher histological grade tumor, and who received breast-conserving surgery had adjuvant chemotherapy. The ACT group did not exhibit better survival in BCSS or OS before PSM. After PSM, the ACT and non-ACT groups consisted of 255 patients, respectively, and Kaplan-Meier curves and multivariate analysis both indicate that adjuvant chemotherapy was not associated with better survival in terms of BCSS or OS. Furthermore, we did not observe any survival advantage in any subgroup irrespective of age, race, marital status, histological grade, surgery type, or radiotherapy status. Conclusions: The study results indicate that there is no strong association between ACT and better survival in T1aN0M0 TNBC. It implies that the chemotherapy decision should be made cautiously and further research into therapeutic strategies are needed in T1aN0M0 TNBC patients.

6.
J Am Chem Soc ; 142(17): 7968-7975, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32266814

RESUMO

Ion migration has been recognized as a critical step in determining the performance of numerous devices in chemistry, biology, and material science. However, direct visualization and quantitative investigation of solid-phase ion migration among anisotropic nanostructures have been a challenging task. Here, we report an in-situ ChemTEM method to quantitatively investigate the solid-phase ion migration process among coassembled nanowires (NWs). This complicated process was tracked within a NW and between NWs with an obvious nanogap, which was revealed by both phase field simulation and ab initio modeling theoretical evaluation. A migration "bridge" between neighboring NWs was observed. Furthermore, these new observations could be applied to migration of other metal ions on semiconductor NWs. These findings provide critical insights into the solid-phase ion migration kinetics occurring in nanoscale systems with generality and offer an efficient tool to explore other ion migration processes, which will facilitate fabrication of customized and new heteronanostructures in the future.

7.
Inorg Chem ; 59(2): 1376-1382, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31891485

RESUMO

Composition modulation is an efficient strategy for improving the performance of Pt-based electrocatalysts for direct methanol fuel cells. Unfortunately, a robust route for the composition modulation of one-dimensional multicomponent nanowire electrocatalysts remains a tremendous challenge. Herein, we report a versatile method for high-quality Pt-based nanowires and nanotubes, which exhibit composition-dependent performance for the methanol oxidation reaction, through a simple solvothermal process. Among these catalysts, quaternary PtRuAgTe nanotubes possess the lowest onset potential of 0.387 V and display the highest activity of 1145 mA mg-1 Pt, which is ∼3.0 times that of commercial Pt/C, exhibiting the best long-term durability over 30000 s owing to the synergistic effect between compositions as well as the favorable tubelike structure. Moreover, synchrotron radiation photoelectron spectroscopy is introduced to investigate the structural behavior of the catalysts before and after the catalytic process. This work contributes a simple method toward scalable production of high-performance Pt-based nanowires and nanotubes for applications in electrocatalysts and affords an inspiring route to enhance both the catalytic activity and the durability.

8.
J Surg Res ; 247: 211-219, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31706539

RESUMO

BACKGROUND: The eighth edition of the American Cancer Joint Committee on Cancer (AJCC) staging system for breast cancer put forward the prognostic stage groups for the first time based on the traditional anatomic tumor-node-metastasis staging system. Our study intends to validate the predictive significance of the eighth edition staging system in triple-negative breast cancer (TNBC) patients. MATERIALS AND METHODS: We collected and accessed 26,589 eligible cases of TNBC from the Surveillance, Epidemiology, and End Results database (2010-2015) and reclassified the patient cohort according to the eighth edition of the AJCC staging system into anatomic and prognostic stages. RESULTS: The results showed that more than half of the patients upstaged in the prognostic stage when compared with the anatomic stage. By comparing with the anatomic stage, the prognostic stage had a higher likelihood ratio and linear trend χ2 values. The prognostic stage group also had higher Akaike information criterion and Bayesian information criterion values than the anatomic stage group. CONCLUSIONS: The prognostic staging system in TNBC patients performs more optimistic prognostic stratification and predictability than the anatomic staging system. Moreover, the latest AJCC staging system has a milestone importance to the history of breast cancer staging system.


Assuntos
Biomarcadores Tumorais/análise , Mama/patologia , Metástase Linfática/patologia , Neoplasias de Mama Triplo Negativas/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Conjuntos de Dados como Assunto , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Receptor ErbB-2/análise , Receptor ErbB-2/genética , Receptores de Estrogênio/análise , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/análise , Receptores de Progesterona/metabolismo , Programa de SEER/estatística & dados numéricos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia , Estados Unidos , Adulto Jovem
9.
J Am Chem Soc ; 141(27): 10729-10735, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31246444

RESUMO

Designing high-efficiency catalyst is at the heart of a transition to future renewable energy systems. Great achievements have been made to optimize thermodynamics to reduce energetic barriers of the catalytic reactions. However, little attention has been paid to design catalysts to improve kinetics to enrich the local concentration of reactant molecules surrounding electrocatalysts. Here, we find that well-designed nanocatalysts with periodic structures can optimize kinetics to accelerate mass-transport from bulk electrolyte to the catalyst surface, leading to the enhanced catalytic performance. This achievement stems from regulation of the surface reactant flux due to the gradient of the microelectric field directing uniformly to the nearest catalyst on ordered pattern, so that all of the reactant molecules are utilized sufficiently for reactions, enabling the boost of the electrocatalytic performance. This novel concept is further confirmed in various catalytic systems and nanoassemblies, such as nanoparticles, nanorods, and nanoflakes.

10.
Cancer Manag Res ; 10: 4393-4400, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30349372

RESUMO

PURPOSE: Neoadjuvant chemotherapy (NAC) plays a pivotal role in the treatment of locally advanced breast cancer (LABC); however, breast cancer is a heterogeneous disease, individual responses to chemotherapy are highly variable. Therefore, the purpose of the current research is to identify biomarkers that can predict the chemotherapeutic response. PATIENTS AND METHODS: We recruited 78 patients with primary breast cancer who underwent taxane- and anthracycline-based NAC; these patients were divided into sensitive and resistant groups according to the Response Evaluation Criteria in Solid Tumors (RECIST) criteria. The microRNA microarray was conducted to explore differentially expressed miRNAs. Quantitative real-time polymerase chain reaction (qRT-PCR) further validated the relationship between miR-4530 and chemosensitivity in breast cancer patients. RESULTS: No significant differences were observed between the two groups regarding the clinicopathological characteristics. miR-4530 showed the most potential involving breast cancer chemosensitivity. Mechanically, RUNX2 was identified one of the direct targets of miR-4530 and responsible for breast cancer chemosensitivity. CONCLUSION: Our results revealed that elevated serum miR-4530 levels may sensitize breast cancer to taxane- and anthracycline-based NAC by suppressing RUNX2; therefore, this miRNA has the potential to be a new biomarker for predicting breast cancer chemosensitivity.

11.
Oncotarget ; 8(3): 4773-4780, 2017 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-27999201

RESUMO

Breast-conserving surgery (BCS) including radiotherapy (RT) has been demonstrated to provide at least equivalent prognosis to mastectomy in early-stage breast cancer. However, studies on triple-negative breast cancer (TNBC) patients are relatively scarce. The current population-based study aimed to investigate the distinct outcomes between BCS+RT and mastectomy in patients with TNBC. Utilizing the Surveillance, Epidemiology, and End Results (SEER) database, we enrolled 11,514 female TNBC cases diagnosed during the years 2010-2013. Those patients were subdivided into BCS+RT (5,469) and mastectomy groups (6,045), and we conducted a survival comparison between the two groups. The endpoints were breast cancer-specific survival (BCSS) and overall survival (OS). In the overall cohort, patients with BCS+RT exhibited distinctly better breast cancer-specific survival (BCSS) (log-rank, p < 0.001) and overall survival (OS) (log-rank, p < 0.001) than did mastectomy patients. When stratifying the TNBC patients according to age, histology grade, TNM stage, tumor size, and lymph node (LN) status, most patients in the BCS+RT group presented with better survival than did the patients in the mastectomy group, except for the grade I (log-rank, p = 0.830, both BCSS and OS) and stage I (log-rank, BCSS, p = 0.127; OS, p = 0.093) patients. In addition, after adjusting for confounding variables by multivariable Cox proportional hazard analysis, BCS+RT still tended to present with higher BCSS and OS. In conclusion, from our study on SEER data, BCS+RT displayed elevated BCSS and OS in TNBC patients compared to mastectomy, at least equally. Our study provided further evidence for surgeons that BCS with RT is available for TNBC patients.


Assuntos
Mastectomia Radical Modificada/métodos , Mastectomia Segmentar/métodos , Neoplasias de Mama Triplo Negativas/radioterapia , Neoplasias de Mama Triplo Negativas/cirurgia , Adulto , Idoso , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Programa de SEER , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
12.
Oncotarget ; 8(4): 6206-6215, 2017 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-28008158

RESUMO

Adenoid cystic carcinoma of the breast (breast-ACC) is a rare and indolent tumor with a good prognosis despite its triple-negative status. However, we observed different outcomes in the present study. Utilizing the Surveillance, Epidemiology, and End Results (SEER) database, we enrolled a total of 89,937 eligible patients with an estimated 86 breast-ACC cases and 89,851 invasive ductal carcinoma (IDC) patients. In our study, breast-ACC among women presented with a higher proportion of triple-negative breast cancer (TNBC), which was more likely to feature well-differentiated tumors, rare regional lymph node involvement and greater application of breast-conserving surgery (BCS). Kaplan-Meier analysis revealed that patients with breast-ACC and breast-IDC patients had similar breast cancer-specific survival (BCSS) and overall survival (OS). Moreover, using the propensity score matching method, no significant difference in survival was observed in matched pairs of breast-ACC and breast-IDC patients. Additionally, BCSS and OS did not differ significantly between TNBC-ACC and TNBC-IDC after matching patients for age, tumor size, and nodal status. Further subgroup analysis of molecular subtype indicated improved survival in breast-ACC patients with hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR+/Her2-) tumors compared to IDC patients with HR+/Her2- tumors. However, the survival of ACC-TNBC and IDC-TNBC patients was similar. In conclusion, ACCs have an indolent clinical course and result in similar outcomes compared to IDC. Understanding these clinical characteristics and outcomes will endow doctors with evidence to provide the same intensive treatment for ACC-TNBC as for IDC-TNBC and lead to more individualized and tailored therapies for breast-ACC patients.


Assuntos
Carcinoma Adenoide Cístico/terapia , Carcinoma Ductal de Mama/terapia , Neoplasias de Mama Triplo Negativas/terapia , Adulto , Idoso , Biomarcadores Tumorais/análise , Carcinoma Adenoide Cístico/química , Carcinoma Adenoide Cístico/mortalidade , Carcinoma Adenoide Cístico/secundário , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/secundário , Diferenciação Celular , Distribuição de Qui-Quadrado , Bases de Dados Factuais , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Pontuação de Propensão , Modelos de Riscos Proporcionais , Fatores de Risco , Programa de SEER , Fatores de Tempo , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/química , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia , Estados Unidos/epidemiologia , Adulto Jovem
13.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(8): 1561-4, 2009 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-19726292

RESUMO

OBJECTIVE: To investigate the pharmacokinetics and bioavailability of ziprasidone tablets in Chinese healthy volunteers. METHODS: A randomized crossover study was performed in 20 healthy volunteers, who received a single oral dose (40 mg) of the test or reference preparation of ziprasidone. Blood samples were collected from the subjects at different time points following the drug administration, and the plasma concentration of ziprasidone was determined using high-performance liquid chromatography. The pharmacokinetic parameters were analyzed by DAS software and the relative bioavailability was calculated according to the formula F=AUC(t)/AUC(r)x100%. RESULTS: For the test and reference preparation, the pharmacokinetics parameter C(max) was 170.7-/+71.3 and 174.4-/+81.6 ng/ml, t(max) 3.73-/+1.87 and 3.69-/+1.84 h, t((1/2)) 5.57-/+1.62 and 5.61-/+1.73 h, AUC(0-t) 1273-/+252.3 and 1296-/+266.9 ng.h.ml(-1), and AUC(0-infinity)1396-/+276.9 and 1407-/+281.5 ng.h.ml(-1), respectively, with the relative bioavailability of (98.3-/+12.6)%. No significant differences were found in the main parameters of the test and reference preparations as analyzed by ANOVA and two- and one-side t-test. CONCLUSION: The test and reference preparation of ziprasidone are bioequivalent.


Assuntos
Povo Asiático , Piperazinas/farmacocinética , Tiazóis/farmacocinética , Administração Oral , Disponibilidade Biológica , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Saúde , Humanos , Piperazinas/administração & dosagem , Piperazinas/efeitos adversos , Comprimidos , Equivalência Terapêutica , Tiazóis/administração & dosagem , Tiazóis/efeitos adversos , Fatores de Tempo , Adulto Jovem
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