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1.
Adv Ther ; 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32410166

RESUMO

INTRODUCTION: This study aims to investigate the relationship between breast white adipose tissue (WAT) inflammation and being overweight or obese, menopausal status, and metabolic syndrome-related indicators in breast cancer patients as well as the association between adipocyte size and the severity of WAT inflammation and body mass index (BMI). METHODS: The crown-like structures (CLS-B) formed by macrophages surrounding dying or dead adipocytes can be used to identify breast WAT inflammation. In this study, breast WAT and fasting blood from 136 Chinese women with breast cancer were collected for analysis. Cluster of differentiation 68 (CD68) immunohistochemical staining was performed to identify CLS-B, and the adipocyte size was measured by hematoxylin and eosin staining. RESULTS: The results showed that breast WAT inflammation usually occurs in overweight/obese breast cancer patients, and the severity of inflammation is positively correlated with adipocyte hypertrophy. We did not observe a direct association between WAT inflammation and menopausal status. In addition, the presence of WAT inflammation is associated with abnormalities in circulating factors associated with metabolic syndrome such as higher serum lipid, glucose, and C-reactive protein levels. CONCLUSION: Overweight/obese breast cancer patients may be more prone to breast WAT inflammation and may be associated with abnormalities in circulatory markers associated with metabolic syndrome.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32249497

RESUMO

A molecularly thin layer of 2-aminobenzenethiol (2-ABT) was adsorbed onto nanoporous p-type silicon (b-Si) photocathodes decorated with Ag nanoparticles (Ag NPs). The addition of 2-ABT alters the balance of the CO2 reduction and hydrogen evolution reactions, resulting in more selective and efficient reduction of CO2 to CO. The 2-ABT adsorbate layer was characterized by Fourier transform infrared (FTIR) spectroscopy and modeled by density functional theory calculations. Ex situ X-ray photoelectron spectroscopy (XPS) of the 2-ABT modified electrodes suggests that surface Ag atoms are in the +1 oxidation state and coordinated to 2-ABT via Ag-S bonds. Under visible light illumination, the onset potential for CO2 reduction was -50 mV vs. RHE, an anodic shift of about 150 mV relative to a sample without 2-ABT. The adsorption of 2-ABT lowers the overpotentials for both CO2 reduction and hydrogen evolution. A comparison of electrodes functionalized with different aromatic thiols and amines suggests that the primary role of the thiol group in 2-ABT is to anchor the NH2 group near the Ag surface, where it serves to bind CO2 and also to assist in proton transfer.

3.
ACS Nano ; 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32323971

RESUMO

Heterojunction photocatalysts are widely adopted for efficient water splitting, but ion migration can seriously threaten the stability of heterojunctions, as with the well-known low stability of CdS-Cu2-xS due to intrinsic Cu+ ion migration. Here, we utilize Cu+ migration to design a stratified CdS-Cu2-xS/MoS2 photocatalyst, in which CuI@MoS2 (CuI-intercalated within the MoS2 basal plane) is created by Cu+ migration and intercalation to the adjacent MoS2 surface. The epitaxial vertical growth of the CuI@MoS2 nanosheets on the surface of one-dimensional core-shell CdS-Cu2-xS nanorods forms catalytic and protective layers to simultaneously enhance catalytic activity and stability. Charge transfer is verified by kinetics measurements with femtosecond time-resolved transient absorption spectroscopy and direct mapping of the surface charge distribution with a scanning ion conductance microscope. This design strategy demonstrates the potential of utilizing hybridized surface layers as effective catalytic and protective interfaces for photocatalytic hydrogen production.

4.
Chem Commun (Camb) ; 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32236200

RESUMO

A high-efficiency top-down approach was used to fabricate orthorhombic MoO3-x nanocrystals through the synergic effect of oleic acid (OA) and oleylamine (OAm), in which OA provided H+ ions and OAm contributed free electrons. This investigation might provide new guidance for manipulating the optical properties of metal oxide semiconductors.

5.
J Voice ; 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32081507

RESUMO

BACKGROUND: Few satisfactory animal models of laryngopharyngeal reflux (LPR) is available. Interleukin-8 (IL-8) and vascular endothelial growth factor (VEGF) may be associated with the pathogenesis of LPR injuries and laryngeal carcinomas. OBJECTIVES: To establish an animal model of LPR and to explore the related pathological changes and cytokine expression in the vocal cord tissue. METHODS: Twenty rabbits were divided into experimental and control groups. Dilatation of the upper and lower esophageal sphincter were carried out in the experimental group. The pH of the pharynx, pathological, and ultrastructural changes of the laryngeal tissue, and expression of IL-8 and VEGF were compared between the experimental group and controls. RESULTS: pH monitoring results and the dilated intercellular space of the vocal cord mucosa showed that the experimental group developed laryngopharyngeal reflux. There were significant differences in the immunohistochemical staining scores of both IL-8 (P = 0.015) and VEGF (P = 0.007) between the experimental and control groups in the vocal cord tissue. CONCLUSIONS: We successfully established a model of LPR, showing histopathological and ultrastructural changes consistent with the disease. The expression of IL-8 and VEGF may increase during the pathogenesis of LPR.

6.
J Phys Chem Lett ; 11(3): 968-973, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31957448

RESUMO

A highly efficient, durable, and cost-effective Fenton-like catalyst is desired to produce the sulfate radicals (•SO4-) for energy and environmental applications. The M(n+1)+/Mn+ redox cycle in metal catalysts requires a high redox potential for •SO4- generation. NiFe layered double hydroxide (LDH) nanosheets with a suitable redox potential for persulfate (PDS) activation were prepared via incorporating Fe into the Ni based LDH. With the help of Fe, the charge-transfer kinetics for the reduction of Ni3+ to Ni2+ was improved and the formation of unwanted Ni component with higher oxidation state was suppressed. The incorporated Fe as the electron transfer mediator enhanced the process of Ni(OH)2/NiOOH redox cycle. Therefore, NiFe LDH exhibited superior performance in PDS activation with exceptionally high activity for the phenolic compounds' degradation in neutral and basic conditions. This work is expected to inspire the rational design of LDHs based catalysts for PDS activation.

7.
Angew Chem Int Ed Engl ; 59(4): 1469-1473, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31680389

RESUMO

The reduced dimension perovskite including 2D perovskites are one of the most promising strategies to stabilize lead halide perovskite. A mixed-cation 2D perovskite based on a steric phenyltrimethylammonium (PTA) cation is presented. The PTA-MA mixed-cation 2D perovskite of PTAMAPbI4 can be formed on the surface of MAPbI3 (PTAI-MAPbI3 ) by controllable PTAI intercalation by either spin coating or soaking. The PTAMAPbI4 capping layer can not only passivate PTAI-MAPbI3 perovskite but also act as MA+ locker to inhibit MAI extraction and significantly enhance the stability. The highly stable PTAI-MAPbI3 based perovskite solar cells exhibit a reproducible photovoltaic performance with a champion PCE of 21.16 %. Such unencapsulated devices retain 93 % of initial efficiency after 500 h continuous illumination. This steric mixed-cation 2D perovskite as MA+ locker to stabilize the MAPbI3 is a promising strategy to design stable and high-performance hybrid lead halide perovskites.

8.
Chem Rec ; 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31833628

RESUMO

Nanoporous silica solids can offer opportunities for hosting photocatalytic components such as various tetra-coordinated transition metal ions to form systems referred to as "single-site photocatalysts". Under UV/visible-light irradiation, they form charge transfer excited states, which exhibit a localized charge separation and thus behave differently from those of bulk semiconductor photocatalysts exemplified by TiO2 . This account presents an overview of the design of advanced functional materials based on the unique photo-excited mechanisms of single-site photocatalysts. Firstly, the incorporation of single-site photocatalysts within transparent porous silica films will be introduced, which exhibit not only unique photocatalytic properties, but also high surface hydrophilicity with self-cleaning and antifogging applications. Secondary, photo-assisted deposition (PAD) of metal precursors on single-site photocatalysts opens up a new route to prepare nanoparticles. Thirdly, visible light sensitive photocatalysts with single and/or binary oxides moieties can be prepared so as to use solar light, the ideal energy source.

9.
Chem Commun (Camb) ; 55(98): 14741-14744, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31754680

RESUMO

Novel all-inorganic Sb-based lead-free double perovskite Cs2AgSbX6 (X = Cl, Br or I) quantum dots exhibiting excellent air stability and strong blue emission with photoluminescence quantum yields of 31.33% were synthesized for the first time using a surfactant-assisted method. The ligand, oleic acid, could control the crystallization of the pure perovskite phase and significantly passivate the surface.

10.
Angew Chem Int Ed Engl ; 58(46): 16691-16696, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31538395

RESUMO

The controllable growth of CsPbI3 perovskite thin films with desired crystal phase and morphology is crucial for the development of high efficiency inorganic perovskite solar cells (PSCs). The role of dimethylammonium iodide (DMAI) used in CsPbI3 perovskite fabrication was carefully investigated. We demonstrated that the DMAI is an effective volatile additive to manipulate the crystallization process of CsPbI3 inorganic perovskite films with different crystal phases and morphologies. The thermogravimetric analysis results indicated that the sublimation of DMAI is sensitive to moisture, and a proper atmosphere is helpful for the DMAI removal. The time-of-flight secondary ion mass spectrometry and nuclear magnetic resonance results confirmed that the DMAI additive would not alloy into the crystal lattice of CsPbI3 perovskite. Moreover, the DMAI residues in CsPbI3 perovskite can deteriorate the photovoltaic performance and stability. Finally, the PSCs based on phenyltrimethylammonium chloride passivated CsPbI3 inorganic perovskite achieved a record champion efficiency up to 19.03 %.

11.
Science ; 365(6453): 591-595, 2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31395783

RESUMO

Although ß-CsPbI3 has a bandgap favorable for application in tandem solar cells, depositing and stabilizing ß-CsPbI3 experimentally has remained a challenge. We obtained highly crystalline ß-CsPbI3 films with an extended spectral response and enhanced phase stability. Synchrotron-based x-ray scattering revealed the presence of highly oriented ß-CsPbI3 grains, and sensitive elemental analyses-including inductively coupled plasma mass spectrometry and time-of-flight secondary ion mass spectrometry-confirmed their all-inorganic composition. We further mitigated the effects of cracks and pinholes in the perovskite layer by surface treating with choline iodide, which increased the charge-carrier lifetime and improved the energy-level alignment between the ß-CsPbI3 absorber layer and carrier-selective contacts. The perovskite solar cells made from the treated material have highly reproducible and stable efficiencies reaching 18.4% under 45 ± 5°C ambient conditions.

12.
Environ Sci Technol ; 53(15): 9081-9090, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31286774

RESUMO

Nanoscale zerovalent iron (nZVI) particles have received much attention in environmental science and technology due to their unique electronic and chemical properties. However, the aggregation and oxidation of nZVI brings much difficulty in practical application of environmental remediation. In this study, we reported a composite nano-Fe(0)/mesoporous carbon by a chelation-assisted coassembly and carbothermal reduction strategy. Nano-Fe(0) particles with surface iron oxide (Fe2O3·FeO) were wrapped with graphitic layers which were uniformly dispersed in mesoporous carbon frameworks. The unique structure made the nano-Fe(0) particles stable in air for more than 20 days. It was used as a peroxydisulfate (PDS) activator for the oxidation treatment of 2,4,6-trichlorophenol (TCP). The TOF value of MCFe for TCP degradation is nearly 3 times higher than those of FeSO4 and Fe2O3·FeO and nearly 2 times than that of commercial nZVI. The reactive oxygen species (ROS) including •SO4-, HO•, and •O2-, 1O2 are efficiently generated by PDS activation with MCFe. The PDS activation process by nano-Fe(0) particles was intrinsically induced by the ferrous ions (Fe(II)) continuously generated at the solid/aqueous interface. Namely, the nano-Fe(0) particles were highly efficiently utilized in sulfate radical-based advanced oxidation processes (SR-AOP). The porous structure also assists the absorption and transfer of TCP during the degradation process.


Assuntos
Recuperação e Remediação Ambiental , Poluentes Químicos da Água , Purificação da Água , Carbono , Ferro , Oxirredução , Água
13.
J Cancer ; 10(12): 2619-2627, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31258769

RESUMO

Objective: As a member of the Wnt family, WNT6 contributes to tumorigenesis and the development of various types of cancer. However, the expression status of WNT6 in colorectal liver metastasis (CRLM) and its prognostic value remain to be elucidated. In this study, we evaluated the association of WNT6 expression with survival outcomes in CRLM patients undergoing liver resection. Methods: The medical records of 106 consecutive CRLM patients undergoing curative tumor resection between October 1996 and December 2011 were retrospectively selected. WNT6 expression was detected using immunohistochemistry (IHC) analyses on paraffin-embedded specimens. The IHC score was determined according to the percentage and intensity of positively stained cells. Recurrence-free survival (RFS) and overall survival (OS) were analyzed using the Kaplan-Meier method and the log-rank test, and independent prognostic factors were determined by Cox regression modeling. Results: We found that WNT6 was commonly expressed in 93.4% (99/106) of colorectal cancer tissues. The median IHC score of WNT6 expression was significantly lower in patients receiving preoperative chemotherapy than those without preoperative chemotherapy (1.33 vs. 2.33, P = 0.033). Survival analysis indicated that patients with high WNT6 expression had poorer 5-year OS than those with low WNT6 expression (31.0% vs. 62.2%, P = 0.012). The 5-year OS rate was significantly lower in the high WNT6 group than in the low WNT6 group (36.8% vs. 79.9%, P = 0.013) in low-risk patients but was comparable among the high-risk patients (22.7% vs. 34.7%, P = 0.433). Multivariate analysis indicated that high WNT6 expression was independently associated with poor OS (hazard ratio [HR]: 2.089; 95% confidence interval [CI]: 1.231-3.545; P = 0.006). Conclusions: High expression of WNT6 was associated with unfavorable oncologic prognosis in patients with CRLM undergoing liver resection. Detection of WNT6 expression may be valuable for guiding postoperative treatment.

14.
Biotechnol Prog ; 35(5): e2867, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31187591

RESUMO

The cyclodextrin glycosyltransferase (CGTase) is an important enzyme for cyclodextrin (CD) production, and is also widely used in the biotechnology, food, and pharmaceuticals industries. Secretory CGTase production by recombinant Komagataella phaffii using defined medium is a promising approach because of low cost, less impurity protein. It was found that no CGTase was expressed using traditional defined medium (basal salt medium [BSM]) because of pH value decreasing significantly. CGTase was expressed by recombinant K. phaffii through pH maintenance in range of 5.5-7.0. ß-CGTase activity increased to 122.0 U/mL after optimization of glycerol, phosphate buffer, pH value, ammonium sulfate, temperature, methanol, and additives based on BSM, establishing a modified defined medium. These results showed that it was necessary to establish recombinant K. phaffii-based special defined medium although the same host cell used for different heterologous protein expression.

15.
Front Plant Sci ; 10: 538, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31114600

RESUMO

Low temperature-induced stress is a major environmental factor limiting the growth and development of plants. Alfalfa (Medicago sativa L.) is a legume well known for its tolerance of extreme environments. In this study, we sought to experimentally investigate the role of rhizobium symbiosis in alfalfa's performance under a low-temperature stress condition. To do this, alfalfa "Ladak+" plants carrying active nodules (AN), inactive nodules (IN), or no nodules (NN) were exposed to an imposed low temperature stress and their survivorship calculated. The antioxidant defense responses, the accumulation of osmotic regulation substances, the cell membrane damage, and the expression of low temperature stress-related genes were determined in both the roots and the shoots of alfalfa plants. We found that more plants with AN survived than those with IN or NN under the same low temperature-stress condition. Greater activity of oxidation protective enzymes was observed in the AN and IN groups, conferring higher tolerance to low temperature in these plants. In addition, rhizobia nodulation also enhanced alfalfa's ability to tolerate low temperature by altering the expression of regulatory and metabolism-associated genes, which resulted in the accumulation of soluble proteins and sugars in the nodulated plants. Taken together, the findings of this study indicate that rhizobium inoculation offers a practical way to promote the persistence and growth potential of alfalfa "Ladak+" in cold areas.

16.
J Phys Chem A ; 123(13): 2674-2678, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30865453

RESUMO

Organometallic halide perovskite solar cells such as MAPbI3 have shown great promise as a low-cost, high-efficiency photovoltaic candidate. Recent studies demonstrated that by substituting an appropriate amount I ions of MAPbI3 with Br ions, the device performance parameters, such as moisture stability or power conversion efficiency, can be further optimized. In this study, using time-resolved optical reflectivity to track the carrier dynamics in MAPb(I1- xBr x)3 films with different Br contents, we found that photocarriers in MAPb(I1- xBr x)3 films with x = 0.01 and 0.02 diffuse much faster than those in films with other Br contents. We suggest that the faster charge carrier diffusion benefits from larger crystal grain size. As a result, this suppresses electron and hole recombination and increases the carrier extraction efficiency, in agreement with the higher power conversion efficiency reported previously.

18.
Dalton Trans ; 48(3): 928-935, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30565614

RESUMO

Tubular hematite with high-concentration, uniform doping is regarded as a promising material for photoelectrochemical water oxidation. However, the high-temperature annealing commonly used for activating doped hematite inevitably causes deformation of the tubular structure and an increase in the trap states. In the present work, Sn-doped tubular hematite on fluorine-doped tin oxide (FTO) is successfully obtained at 750 °C from a Sn-coated FeOOH tube precursor. Sn/P codoping, which is rarely considered for hematite, is also achieved via a gas phase reaction in phosphide atmosphere. The tubular morphology allows the dopant to diffuse from both the inner and outer surfaces, thus decreasing the doping profile in the radial direction. The even distribution of Sn and P synergetically increases the carrier density of hematite by one order of magnitude, which shortens the width of the depletion layer to ca. 2.3 nm (compared with 19.3 nm for the pristine sample) and leads to prolonged carrier lifetime and efficient charge separation. In addition, this codoping protocol does not introduce additional surface trap states, as evidenced by the increased charge injection efficiency and surface kinetic analysis using intensity modulated photocurrent spectroscopy (IMPS). As a result, the morphology- and doping-engineered hematite exhibits photocurrents of 0.9 mA cm-2 at 1.23 V and 3.8 mA cm-2 at 2.0 V vs. RHE under AM 1.5 G illumination (100 mW cm-2) in 1.0 M NaOH, representing 4.5-fold and 4.8-fold enhancements, respectively, compared with the photocurrents of undoped hematite. The present method is shown to be effective for preparing multi-element-doped hematite nanotubes and may find broad application in the development of other nanotubular photoelectrodes with or without doping for efficient and robust water oxidation.

19.
J Cancer ; 9(24): 4635-4641, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30588247

RESUMO

Background: Cancer-associated fibroblasts (CAFs) have been shown to be among the most prominent cells in tumor microenvironment and play a significant role in accelerating tumor metastasis by interacting with other type of cells. Tumor-associated macrophages (TAMs), the predominant tumor-infiltrating immune cells, also play important roles in cancer progression. Here, we aimed to evaluate the effects of CAFs on infiltration of TAMs and lymphatic metastasis in triple-negative breast cancer (TNBC). Material and methods: The study included 278 patients with histologically confirmed TNBC. Immunohistochemical staining of α-smooth muscle actin and fibroblast activation protein were used to identify CAFs. Polarized functional status of infiltrated TAMs was detected by expression of CD163. The clinicopathological features were assessed from all the patients' medical records. Results: The CAFs-related markers were found to be expressed more frequently in TNBC patents with aggressive behaviors, including recurrence and poor histological differentiation. High activation of CAFs was positively correlated with elevated infiltration of polarized CD163-positive TAMs and lymph node metastasis in TNBC patients. Multivariate Cox analysis revealed that the activation of CAFs, TAMs infiltration, and lymph node metastasis were independent prognostic factors for disease-free survival in TNBC patients. Conclusion: Cancer-associated fibroblasts were associated with infiltration of CD163-positive macrophages and lymphatic metastasis, and may be potential prognostic predictors of TNBC.

20.
Cancer Med ; 7(11): 5394-5410, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30318850

RESUMO

Recent scientific evidence has suggested that long noncoding RNAs (lncRNAs) play an important part in tumorigenesis as an important member of competing endogenous RNAs (ceRNAs). Hundreds of RNA sequence data and relevant clinic information are freely accessible in The Cancer Genome Atlas (TCGA) datasets. However, the role of cancer-related lncRNAs in papillary thyroid cancer (PTC) is not fully understood yet. In this study, we identified 461 RNA sequencing data from TCGA. Subsequently, 45 lncRNAs, 21 miRNAs, and 78 mRNAs were chosen to construct a ceRNA network of PTC. Then, we analyzed the correlation between these 45 PTC-specific lncRNAs and clinic features and patient outcome. Thirty-seven of these lncRNAs were found to be closely related to age, race, gender, lymph node metastasis, TNM staging system, and patient outcome. Additionally, three of them were linked to PTC patient overall survival. Eventually, we selected eight lncRNAs randomly and performed quantificational real-time polymerase chain reaction (qRT-PCR) in 28 newly diagnosed patients with PTC to verify the reliability of the above results. The results of qRT-PCR are totally in agreement with the bioinformatics analysis. Additionally, it was found that HAND2-AS1 was negatively related to tumor size (P < 0.05). The results were consistent with the bioinformatics analysis in TCGA. Taken together, we identified the differentially expressed lncRNAs and constructed a PTC ceRNA network. The study provides a new perspective and supplement for our understanding of lncRNAs in PTC development and reveals potential diagnostic and prognostic markers in PTC.


Assuntos
Metástase Linfática/genética , Metástase Linfática/patologia , RNA , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Adulto , Progressão da Doença , Feminino , Redes Reguladoras de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Análise de Sequência de RNA
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