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1.
Nanoscale Adv ; 6(6): 1781-1789, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38482037

RESUMEN

Photocatalytic nitrogen (N2) reduction to ammonia (NH3), adopting H2O as the electron source, suffers from low efficiency owing to the sluggish kinetics of N2 reduction and the requirement of a substantial thermodynamic driving force. Herein, we present a straightforward approach for the construction of an S-scheme heterojunction of BiVO4/VS-MoS2 to successfully achieve photocatalytic N2 fixation, which is manufactured by coupling an N2-activation component (VS-MoS2 nanosheet) and water-oxidation module (BiVO4 nanocrystal) through electrostatic self-assembly. The VS-MoS2 nanosheet, enriched with sulfur vacancies, plays a pivotal role in facilitating N2 adsorption and activation. Additionally, the construction of the S-scheme heterojunction enhances the driving force for water oxidation and improves charge separation. Under simulated sunlight irradiation (100 mW cm-2), BiVO4/VS-MoS2 exhibits efficient photocatalytic N2 reduction activity with H2O as the proton source, yielding NH3 at a rate of 132.8 µmol g-1 h-1, nearly 7 times higher than that of pure VS-MoS2. This study serves as a noteworthy example of efficient N2 reduction to NH3 under mild conditions.

2.
Chem Biol Drug Des ; 103(3): e14507, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38538070

RESUMEN

Non-small cell lung cancer (NSCLC) is an aggressive and devastating cancer due to its metastasis induced by increased invasion. Lentinan is a polysaccharide exerting antitumor roles in multiple cancers, including lung cancer. However, the influence of lentinan on cell invasion in NSCLC remains unclear. Cell invasion was detected by transwell analysis. Matrix metallopeptidase 9 (MMP9) levels were measured through immunofluorescence staining. The markers arginase-1 (Arg-1), CD206 and interleukin (IL)-10 (IL-10) of M2 macrophages, Wnt3a, and ß-catenin levels were measured by western blot or enzyme linked immunosorbent assay. Lentinan did not affect cell viability and proliferation in NSCLC cells. Lentinan suppressed cell invasion and reduced the expression and secretion of MMP9. Lentinan attenuated also M2 polarization of tumor-associated macrophages. Moreover, lentinan mitigated the M2 macrophage conditioned medium-mediated cell invasion and MMP9 alterations in NSCLC cells. Lentinan inhibited the activation of the Wnt/ß-catenin signaling in NSCLC cells. The activated Wnt/ß-catenin pathway reversed the suppressive effects of lentinan on cell invasion and MMP9 level in NSCLC cells. In conclusion, lentinan reduces cell invasion in NSCLC cells by inhibiting the M2 polarization of tumor-associated macrophages and the Wnt/ß-catenin signaling.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Lentinano , Neoplasias Pulmonares , Humanos , beta Catenina/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Lentinano/farmacología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Metaloproteinasa 9 de la Matriz , Macrófagos Asociados a Tumores/efectos de los fármacos , Macrófagos Asociados a Tumores/metabolismo , Macrófagos Asociados a Tumores/patología
3.
Angew Chem Int Ed Engl ; 63(21): e202401344, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38422378

RESUMEN

The development of high-performance photocatalytic systems for CO2 reduction is appealing to address energy and environmental issues, while it is challenging to avoid using toxic metals and organic sacrificial reagents. We here immobilize a family of cobalt phthalocyanine catalysts on Pb-free halide perovskite Cs2AgBiBr6 nanosheets with delicate control on the anchors of the cobalt catalysts. Among them, the molecular hybrid photocatalyst assembled by carboxyl anchors achieves the optimal performance with an electron consumption rate of 300±13 µmol g-1 h-1 for visible-light-driven CO2-to-CO conversion coupled with water oxidation to O2, over 8 times of the unmodified Cs2AgBiBr6 (36±8 µmol g-1 h-1), also far surpassing the documented systems (<150 µmol g-1 h-1). Besides the improved intrinsic activity, electrochemical, computational, ex-/in situ X-ray photoelectron and X-ray absorption spectroscopic results indicate that the electrons photogenerated at the Bi atoms of Cs2AgBiBr6 can be directionally transferred to the cobalt catalyst via the carboxyl anchors which strongly bind to the Bi atoms, substantially facilitating the interfacial electron transfer kinetics and thereby the photocatalysis.

4.
Angew Chem Int Ed Engl ; 63(17): e202401604, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38414115

RESUMEN

Formamidinium lead triiodide serves as the optimal light-absorbing layer in single-junction perovskite solar cells. However, achieving operational stability of high-efficiency n-i-p type devices at elevated temperatures remains challenging. In this work, we implemented effective surface modifications on microcrystalline perovskite films. This involved the nucleophilic addition of formamidinium cations and coordination of residual PbI2 with triphenylmethane triisocyanate as well as subsequent polymerization. The in situ growth of a cross-linking network chemically anchored on the perovskite film in this approach effectively reduced trap densities, favorably altered surface work function, suppressing interface charge recombination and thus enhancing cell efficiency. Coupled with a high-melting-point air-doping promoter, we fabricated n-i-p type perovskite solar cells surpassing 25 % efficiency, demonstrating excellent operational stability at 65 °C.

5.
Adv Ther ; 40(4): 1590-1600, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36773079

RESUMEN

BACKGROUND: The expression of signaling molecules downstream of the mammalian target of rapamycin (mTOR) is dysregulated in patients with rheumatic fever (RF), but the causality of mTOR on RF remains unknown. This study aimed to investigate the causal effects of the mTOR-dependent proteins in RF. METHODS: The summary data for targets of the mTOR signaling were acquired from the publicly available INTERVAL study GWAS data. Data on RF have been obtained from the Integrated Epidemiology Unit GWAS database (38,209 cases and 156,711 healthy controls). A two-sample Mendelian randomization (MR) study was conducted to examine the association of RF risk and mTOR-dependent proteins (EIF4EBP2, EIF-4E, EIF-4G, EIF-4A, RP-S6K, and ATG7), including the inverse-variance weighted (IVW) method, MR-Egger, and weighted median, which was followed by sensitivity analyses. RESULTS: RP-S6K is associated with a lowered risk of RF with an odds ratio (OR) of 0.97, 95% confidence interval (95% CI) of 0.94-0.99 (p = 0.027). In contrast, ATG7 accounts for higher risk of RF with an OR of 1.05 (95% CI = 1.00-1.12, p = 0.047). No apparent heterogeneity and no horizontal pleiotropy were observed in the sensitivity analysis (p > 0.05). No statistical significance was identified for levels of EIF4A, EIF4G, EIF4E-BP2, and RP-S6K with RF risk (p > 0.05). CONCLUSION: MR found robust evidence of a causal association between RF and mTOR. RP-S6K and ATG7 may be targeted for intervention by repurposing existing therapeutics to reduce the risk of RF.


Asunto(s)
Fiebre Reumática , Humanos , Fiebre Reumática/genética , Causalidad , Bases de Datos Factuales , Oportunidad Relativa , Sirolimus , Serina-Treonina Quinasas TOR , Polimorfismo de Nucleótido Simple
6.
Autoimmun Rev ; 21(9): 103156, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35896124

RESUMEN

OBJECTIVE: The breakdown of immune tolerance mediated by the reduced regulatory T (Treg) cell contributes to autoimmune diseases, which can be recovered by the short-term and low-dose interleukin 2 (IL-2). However, the role of Treg cells in microscopic polyangiitis (MPA) and the efficacy of short-term and low-dose IL-2 for MPA remain unclear. Therefore, we performed a retrospective study to explore the role of Treg cells and evaluate the efficacy of short-term and low-dose IL-2 therapy in MPA. METHODS: 52 MPA were collected as research objects, and 15 of them voluntarily received short-term and low-dose IL-2 subcutaneous injection combined with conventional therapy. 60 volunteers were recruited as health controls (HC) according to the inclusion and exclusion criteria. The number of circulating CD4 + T cell subsets was detected by flow cytometry. RESULTS: Patients with MPA had reduced circulating Treg cells than HCs (P < 0.001), and the level of Treg cells were reduced in MPA-activity and ANCA-positive group (P = 0.018 and P = 0.008 respectively). The patients with lower Treg cells had the higher incidence of the organ involvement (P = 0.006). The level of Treg cells in MPA was doubled after the short-term and low-dose IL-2 combined with conventional therapy (P = 0.001), and the disease activity indicators such as ESR and CRP were improved (P < 0.05) with no apparent side effects. CONCLUSION: Patients with MPA had reduced circulating Treg cells, especially the MPA-activity and ANCA-positive patients. And the patients with lower Treg cells were more likely to exhibit the organ involvement. Short-term and low-dose IL-2 therapy increased the reduced Treg cells and promoted the remission of the disease at a certain extent with well tolerance.


Asunto(s)
Poliangitis Microscópica , Linfocitos T Reguladores , Anticuerpos Anticitoplasma de Neutrófilos , Humanos , Interleucina-2/uso terapéutico , Poliangitis Microscópica/tratamiento farmacológico , Estudios Retrospectivos
7.
J Oncol ; 2022: 8204818, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35466319

RESUMEN

Gastric cancer (GC) is the second leading cause of tumor-associated death and the fourth most commonly seen tumor across the world. Abnormal ncRNAs have been verified to be involved in potential metastasis via modulating epithelial-to-mesenchymal transition progression and are vital for the progression of cancers. Tumor-infiltrating immune cells (TICs) are a vital indicator of whether cancer patients will benefit from immunotherapy. Nonetheless, the association between ceRNAs and immune cells remained largely unclear. We used the ceRNA network combined with TICs for the prediction of the clinical outcome of GC patients based on TCGA datasets. The percentage of immunocytes in GC was speculated by the use of CIBERSORT. Via Lasso and multivariate assays, prognostic models were established applying survival-related genes and immune cells. Nomograms were developed, and the accuracy of the nomograms was determined using calibration curves. The association between ceRNAs and TICs was validated by the use of integration analysis. In this study, there were 2219 mRNAs (1308 increased and 911 decreased), 171 lncRNAs (51 decreased and 120 increased), and 123 miRNAs (55 decreased and 68 increased) differentially expressed between tumor groups and nontumor groups. Five lncRNAs, six miRNAs, and 64 mRNAs were used for ceRNA network construction. Eight genes including LOX, SPARC, MASTL, PI15, BMPR1B, ANKRD13B, PVT1, and miR-7-5p were applied for the development of the prognostic model. Survival assays suggested that tumor cases with high risk exhibited a shorter overall survival. In addition, we included T-cell CD4 memory activated, monocytes, and neutrophils for the development of a prognosis model. Eventually, our team demonstrated the possible associations between the ceRNA prognosis model and prognostic model based on immune cells. To sum up, the ceRNA network could be used for gene regulation and predict clinical outcomes of GC patients.

8.
ACS Omega ; 7(1): 1420-1427, 2022 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-35036803

RESUMEN

In the present work, experimental and kinetic studies are conducted to explore and model tobacco pyrolysis characteristics under a wide range of heating conditions. First, thermal decomposition processes of a tobacco sample were investigated using thermogravimetric analysis/difference thermogravimetry (TGA/DTG) experiments under a wide range of heating rates (10-500 K/min), and the TGA/DTG profiles were compared to highlight the effect of heating rate on the pyrolysis characteristics. The results showed that the tobacco sample was sufficiently devolatilized at 1173.15 K (900 °C) and the final volatiles yields were not sensitive to the heating rate. Moreover, it was illustrated that the DTG curve presents a polymerization trend with the increase in heating rate. Then, kinetic parameters, including total component mass fraction, preexponential factor, and activation energy, were derived by deconvolution from TG/DTG profiles for each component with a one-step kinetic framework, and the correlations between kinetic parameters and heating rates were further explored and modeled. The results illustrated that four subpeaks can be found in the deconvolution, indicating the four components (volatile components, hemicellulose, cellulose, and lignin). In addition, the activation energy of each component was found to be insensitive with heating rate (with standard deviation less than 20%). Therefore, an average activation energy was used for each component to avoid the compensation effect and a power correlation between the heating rate and the preexponential factor could be found. A posteriori analysis also confirmed the validity of this correlation.

9.
ACS Appl Mater Interfaces ; 13(19): 22314-22322, 2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-33961390

RESUMEN

Up to now, the majority of the developed photocatalytic CO2 reduction systems need to use expensive sacrificial reductants as electron source. It is still a huge challenge to drive the photocatalytic CO2 reduction using water as an electron source. Herein, we report a facile strategy for the construction of direct Z-scheme heterojunction of LF-FAPbBr3/α-Fe2O3, which is manufactured by the in situ and two-step controlled growth of ligand-free formamidinium lead bromide (LF-FAPbBr3) nanocrystals on the surface of α-Fe2O3 nanorods. The matchable energy levels and direct contact between LF-FAPbBr3 and α-Fe2O3 significantly accelerate the interfacial charge transfer, with a charge separation efficiency (ηseparation) of 93%, much higher than that of 11% shown by the ligand-capped FAPbBr3/α-Fe2O3 heterojunction. The resulting efficient separation and raised redox ability of photogenerated carriers endow the LF-FAPbBr3/α-Fe2O3 heterojunction with an outstanding photocatalytic performance for CO2 reduction (to CO and CH4) coupled with water oxidation (to O2), achieving a highest electron consumption rate of 175.0 µmol g-1 h-1 among the reported metal halide perovskite-based photocatalysts, which are 5 and 11 times higher in comparison with those of sole LF-FAPbBr3 and ligand-capped FAPbBr3/α-Fe2O3, respectively.

10.
Chemistry ; 27(7): 2305-2309, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33107087

RESUMEN

Capping ligands are indispensable for the preparation of metal-halide-perovskite (MHP) nanocrystals (NCs) with good stability; however, the long alkyl-chain capping ligands in conventional MHP NCs will be unfavorable for CO2 adsorption and hinder the efficient carrier separation on the surface of MHP NCs, leading to inferior catalytic activity in artificial photosynthesis. Herein, CsPbBr3 nanocrystals with short-chain glycine as ligand are constructed through a facile ligand-exchange strategy. Owing to the reduced hindrance of glycine and the presence of the amine group in glycine, the photogenerated carrier separation and CO2 uptake capacity are noticeably improved without compromising the stability of the MHP NCs. The CsPbBr3 nanocrystals with glycine ligands exhibit a significantly increased yield of 27.7 µmol g-1 h-1 for photocatalytic CO2 -to-CO conversion without any organic sacrificial reagents, which is over five times higher than that of control CsPbBr3 NCs with conventional long alkyl-chain capping ligands.

11.
Small ; 16(29): e2002140, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32510866

RESUMEN

The judicious design of efficient electron mediators to accelerate the interfacial charge transfer in a Z-scheme system is one of the viable strategies to improve the performance of photocatalysts for artificial photosynthesis. Herein, ultrathin and small-size graphene oxide (USGO) nanosheets are constructed and employed as the electron mediator to elaborately exploit an efficient CsPbBr3 -based all-solid-state Z-scheme system in combination with α-Fe2 O3 for visible-light-driven CO2 reduction with water as the electron source. CsPbBr3 and α-Fe2 O3 can be closely anchored on USGO nanosheets, owing to the existence of interfacial strong chemical bonding behaviors, which can significantly accelerate the photogenerated carrier transfer between CsPbBr3 and α-Fe2 O3 . The resultant improved charge separation efficiency endows the Z-scheme system exhibiting a record-high electron consumption rate of 147.6 µmol g-1 h-1 for photocatalytic CO2 -to-CO conversion concomitant with stoichiometric O2 from water oxidation, which is over 19 and 12 times higher than that of pristine CsPbBr3 nanocrystals and the mixture of CsPbBr3 and α-Fe2 O3 , respectively. This work provides a novel and effective strategy for improving the catalytic activity of halide-perovskite-based photocatalysts, promoting their practical applications in the field of artificial photosynthesis.

12.
Chem Commun (Camb) ; 56(34): 4664-4667, 2020 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-32211647

RESUMEN

A halide perovskite based photocatalyst has been demonstrated for the first time to simultaneously achieve efficient photocatalytic CO2 reduction and methanol oxidation, exhibiting an exciting yield of 1835 µmol g-1 for photocatalytic CO2-to-CO conversion. Moreover, almost stoichiometric value-added formic acid can be produced from methanol oxidation.

13.
ChemSusChem ; 12(21): 4769-4774, 2019 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-31498955

RESUMEN

Lead halide perovskite (LHP) nanocrystals have recently been actively investigated for photocatalysis, owing to their inexpensive fabrication and excellent optoelectronic properties. However, LHP nanocrystals have not been used for artificial photosynthesis in aqueous solution, owing to their high sensitivity to water. In this study, water-tolerant cobalt-doped CsPbBr3 /Cs4 PbBr6 nanocrystals have been prepared with the protection of hexafluorobutyl methacrylate. The resultant materials are employed as efficient photocatalysts for visible-light-driven CO2 reduction in pure water. The perovskite nanocrystals with 2 % cobalt doping afford an impressive overall yield of 247 µmol g-1 for photocatalytic CO2 conversion into CO and CH4 , using water as an electron source. This study represents a significant step for practical artificial photosynthesis by using LHP nanocrystals as photocatalysts in aqueous solution.

14.
Angew Chem Int Ed Engl ; 58(28): 9491-9495, 2019 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-31066965

RESUMEN

Improving the stability of lead halide perovskite quantum dots (QDs) in a system containing water is the key for their practical application in artificial photosynthesis. Herein, we encapsulate low-cost CH3 NH3 PbI3 (MAPbI3 ) perovskite QDs in the pores of earth-abundant Fe-porphyrin based metal organic framework (MOF) PCN-221(Fex ) by a sequential deposition route, to construct a series of composite photocatalysts of MAPbI3 @PCN-221(Fex ) (x=0-1). Protected by the MOF the composite photocatalysts exhibit much improved stability in reaction systems containing water. The close contact of QDs to the Fe catalytic site in the MOF, allows the photogenerated electrons in the QDs to transfer rapidly the Fe catalytic sites to enhance the photocatalytic activity for CO2 reduction. Using water as an electron source, MAPbI3 @PCN-221(Fe0.2 ) exhibits a record-high total yield of 1559 µmol g-1 for photocatalytic CO2 reduction to CO (34 %) and CH4 (66 %), 38 times higher than that of PCN-221(Fe0.2 ) in the absence of perovskite QDs.

15.
RSC Adv ; 9(59): 34342-34348, 2019 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-35529999

RESUMEN

Metal-halide perovskite nanocrystals have emerged as one of the promising photocatalysts in the photocatalysis field owing to their low-cost and excellent optoelectronic properties. However, this type of nanocrystals generally displays low activity in photocatalytic CO2 reduction owing to the lack of intrinsic catalytic sites and insufficient charge separation. Herein, we functionalized CsPbBr3 nanocrystals with graphitic carbon nitride, containing titanium-oxide species (TiO-CN) to develop an efficient composite catalyst system for photocatalytic CO2 reduction using water as the electron source. Compared to its congener with pristine CsPbBr3, the introduction of TiO-CN could not only increase the number of active sites, but also led to a swift interfacial charge separation between CsPbBr3 and TiO-CN due to their favorable energy-offsets and strong chemical bonding behaviors, which endowed this composite system with an obviously enhanced photocatalytic activity in the reduction of CO2 to CO with water as the sacrificial reductant. Over 3-fold and 6-fold higher activities than those of pristine CsPbBr3 nanocrystals and TiO-CN nanosheets, respectively, were observed under visible light irradiation. Our study provides an effective strategy for improving the photocatalytic activity of metal-halide perovskite nanocrystals, thus promoting their photocatalytic application in the field of artificial photosynthesis.

16.
Neuropsychiatr Dis Treat ; 14: 1527-1533, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29942131

RESUMEN

BACKGROUND: Depressive and anxiety symptoms could seriously affect the quality of life of type 2 diabetes mellitus (T2DM) subjects. Currently, little is known about the efficacy and acceptability of agomelatine versus fluoxetine in treating these symptoms in T2DM subjects. Therefore, this study was performed to find out which one was better in treating these symptoms in T2DM subjects. MATERIALS AND METHODS: T2DM subjects with depressive and anxiety symptoms were randomly assigned to receive either fluoxetine (30-40 mg/day) or agomelatine (25-50 mg/day). The treatment was continued for 12 weeks. The data of the Hamilton Depression Rating Scale (HDRS) and Hamilton Anxiety Rating Scale (HARS) were collected (at baseline and also at weeks 4, 8 and 12) to assess the depressive and anxiety symptoms, respectively. The metabolic parameters, including body mass index (BMI), fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c), were assessed at baseline and after 12 weeks of treatment. The treatment-related adverse events during the scheduled treatment period were recorded to compare the acceptability of these two drugs. RESULTS: After 12 weeks of treatment, the average HDRS and HARS scores were significantly decreased in both groups. The average HDRS scores were not significantly different between the two groups, although the agomelatine group had a lower average HDRS score. The response and remission rates were similar between the two groups, and these two drugs had no significant effects on BMI and FPG. However, compared with the fluoxetine group, the agomelatine group had the significantly lower average HARS score (p=0.0017) and lower average HbA1c level (p<0.00001). Moreover, the incidence of adverse events was significantly lower in the agomelatine group than in the fluoxetine group (p=0.032). CONCLUSION: Both fluoxetine and agomelatine could effectively reduce depressive and anxiety symptoms in T2DM subjects, but agomelatine might be more effective and acceptable. Future studies with more subjects are needed to support and validate our conclusion.

17.
RSC Adv ; 8(17): 9409-9413, 2018 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35541882

RESUMEN

Chemical doping is a viable tactic to improve the charge transporting properties of organic semiconductors in efficient perovskite solar cells. In this paper, we first employ the low-cost inorganic salt FeCl3 as a chemical dopant to replace the traditional expensive cobalt complex for the oxidization of 2,2',7,7'-tetrakis(N,N-p-dimethoxyphenylamino)-9,9'-spirobifluorene (Spiro-OMeTAD), a typical organic hole-transporter. Based on the joint measurements of electron absorption spectra, cyclic voltammetry, and the hole-only device, we reveal that FeCl3 can effectively oxidize Spiro-OMeTAD and improve the hole transporting properties of Spiro-OMeTAD. Through carefully optimizing the dopant concentration, solar cells with 80% FeCl3 doped Spiro-OMeTAD achieve over 17% power conversion efficiency based on a triple cation perovskite photoactive layer, which is comparable to that of devices with a classical cobalt complex dopant. Our work demonstrates the potential of using FeCl3 as a low-cost chemical dopant for hole-transporting materials in perovskite solar cells.

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