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1.
Inorg Chem ; 63(9): 4017-4021, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38367266

RESUMEN

As one of the potential candidates of nonlinear-optical (NLO) materials, rare-earth chalcophosphates have demonstrated promising properties. Here, KREP2S6 (RE = Sm, Gd, Tb, Dy) were synthesized using the facile RE2O3-B-S solid-state method. They crystallize with a monoclinic chiral P21 structure, and their layer structures are built by isolated ethane-like P2S6 dimers and RES8 bicapped trigonal prisms built {[RE2S15]24-}∞ layers. By comparing the structures with related ones, the change of the alkali metal or RE3+ ions can cause structural transformation. Their band gaps are tunable between 2.58 and 3.79 eV, and their powder samples exhibit good NLO properties. Theoretical calculations suggest that the NLO properties are mainly contributed by P2S6 units and {[RE2S15]24-}∞ layers synergistically, in which {[RE2S15]24-}∞ layers and P2S6 units dominate the contribution to the band gap and second-harmonic-generation response, respectively. This work enriches the application of rare-earth chalcophosphates as NLO materials.

2.
Inorg Chem ; 62(49): 19843-19847, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38032849

RESUMEN

Rare-earth (RE) chalcophosphates have been widely studied because of their abundant structures. Here, five new RE selenophosphates, NaREP2Se6 (RE = Y, Sm, Gd-Dy), were synthesized by a facile RE oxide-boron-selenium solid-state route. They crystallize in the triclinic P1̅ space group, featuring three-dimensional (3D) structures constructed by RESe8 and P2Se6 motifs, different from common 2D RE chalcophosphates A-RE-P2-Q6 (A = alkali metal; Q = S, Se) system. Their structural chemistry and relationship with related phases are analyzed. Both the size of A and the coordination geometry of RE have important influences on the system's structures. Their optical band gaps are tunable from 1.79 to 2.50 eV, and they exhibit diverse magnetic behaviors, including Van-Vleck-type paramagnetism, antiferromagnetism, and ferromagnetism. Their photocurrent responses and thermal stabilities are analyzed as well. Calculation results suggest that the RESe8 and P2Se6 units make a great contribution to the optical properties. This work enriches the chemistry and multifunctional properties of RE chalcophosphates.

3.
Small ; 19(8): e2206910, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36504482

RESUMEN

Rare-earth (RE) chalcogenides have been extensively studied as infrared nonlinear optical (NLO) materials because of their nice integrated performances; however, very few RE chalcophosphates are involved for this topic. Here, three quaternary RE selenophosphates, KSmP2 Se6 (1), KGdP2 Se6 (2), and KTbP2 Se6 (3), are profoundly studied for their NLO potentials. Their noncentrosymmetric P21 structures feature RESe8-bicapped trigonal prisms and ethane-like [P2 Se6 ]4 - dimers built {[REP2 Se6 ]-}∞ layers. As the first studied NLO-active RE selenophosphates, 1-3 exhibit second harmonic generation (SHG)responses ≈0.34-1.08 × AgGaS2 at 2.10 µm and laser-induced damage thresholds (LIDTs) ≈1.43-4.33 × AgGaS2 , and they all show phase-matchable behaviors, indicating their wonderful balanced NLO properties. Theoretical calculations demonstrate that the synergistic effect between RESe8 and P2 Se6 units makes the major contribution to the SHG responses.

4.
Zhongguo Zhong Yao Za Zhi ; 47(22): 6217-6226, 2022 Nov.
Artículo en Chino | MEDLINE | ID: mdl-36471948

RESUMEN

To investigated the mechanisms underlying the effects of modified Kaixin San(MKXS) on improving memory and synaptic damage of Alzheimer's disease(AD) mouse model with conditional presenilin 1/2 conditional double knockout(PS cDKO). Specifically, 60 PS cDKO mice(3-3.5 months old) and their age-matched wild-type(WT) littermates were randomized into three groups: WT group(n=20), PS cDKO group(n=20), and PS cDKO+MKXS group(n=20). Mice in WT and PS cDKO groups were fed with standard chow and those in PS cDKO+MKXS group were given chow containing MKXS(at 2.55 g·kg~(-1)) for 60 days. Novel object reco-gnition task was employed to detect the recognition memory of mice, and Western blot to detect the protein levels of synapse-associated proteins in the hippocampus(HPC) of mice, such as NR1, NR2 A, NR2 B, p-αCaMKⅡ, tau, and p-tau. Microglial morphology in the HPC CA1 of mice was observed based on immunohistochemistry. Quantitative real time-PCR(qRT-PCR) was employed to detect the mRNA levels of the pro-inflammatory factors and synapse-associated proteins in the HPC of mice, including COX-2, iNOS, IL-1ß, IL-6, TNF-α, PSD95, NR1, NR2 A, NR2 B, and MAP2. The protein levels of IL-1ß, TNF-α, and IL-6 were tested by enzyme-linked immunosorbent assay(ELISA). The interaction between PSD95 and αCaMKⅡ and between PSD95 and p-αCaMKⅡ was tested by co-immunoprecipitation(Co-IP). The results showed that PS cDKO+MKXS demonstrated significantly higher preference index and recognition index of the new objects, lower protein level of p-tau(ser 396/404) and mRNA levels of COX-2, iNOS, TNF-α, IL-1ß, and IL-6 in HPC, higher protein levels of NR1, NR2 A, NR2 B, and p-αCaMKⅡ and mRNA levels of NR1, NR2 A, NR2 B, PSD95, and MAP2, and stronger interaction of αCaMKⅡ with PSD95 and interaction of p-αCaMKⅡ with PSD95 than the PS cDKO group. Immunohistoche-mical staining showed that MKXS inhibited the activation of microglia. In conclusion, MKXS improves memory and synaptic damage in mice with AD by modulating αCaMKⅡ-PSD95 protein binding through inhibition of neuroinflammation.


Asunto(s)
Enfermedad de Alzheimer , Animales , Ratones , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/genética , Homólogo 4 de la Proteína Discs Large/genética , Homólogo 4 de la Proteína Discs Large/metabolismo , Enfermedades Neuroinflamatorias , Factor de Necrosis Tumoral alfa/metabolismo , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Interleucina-6/metabolismo , Unión Proteica , Ratones Noqueados , Hipocampo/metabolismo , Modelos Animales de Enfermedad , ARN Mensajero/metabolismo
5.
Ann Transl Med ; 10(4): 184, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35280394

RESUMEN

Background: Breast cancer (BRCA) is the most common malignancy with high heterogeneity in women, and the prognostic prediction for BRCA has remained poor. Ferroptosis, a recently identified iron-dependent form of programmed cell death, plays a significant role in BRCA treatment. Some BRCA cell lines are proven to be sensitive to ferroptosis, and some ferroptosis-related genes have been identified as divers or suppressors in the progress of BRCA. This study aimed to explore the prognostic value of ferroptosis-related genes in BRCA. Methods: A ferroptosis-related gene list, messenger RNA (mRNA) gene expression of BRCA patients, and corresponding clinicopathological data were collected from public databases. The patients of the Cancer Genome Atlas (TCGA) were identified as the training cohort, and the ones of the Gene Expression Omnibus (GEO) were looked as the validation cohort. Univariate Cox regression analysis was utilized to identify prognostic ferroptosis-related genes, and subsequent multivariate analysis further screened out important genes to establish a prognostic model. Receiver operating characteristic (ROC) curves were used to validate the model in both internal and external cohorts. Functional analysis was generated to evaluate the potential correlation between tumor immunity and ferroptosis-related genes in BRCA. Results: A ferroptosis-related gene signature stratifying patients into 2 risk score groups was established based on the TCGA cohort, and validated in the GEO cohort. Patients with lower risk scores had better overall survival (OS) compared to those with higher risk scores (P<0.001, TCGA cohort; P<0.05, GEO cohort). The risk score was independently associated with the OS of BRCA patients (P<0.001, TCGA cohort; P<0.05, GEO cohort). The area under the curves (AUCs) of the model in the training and validation cohorts were all around 0.7. Immune-related biological pathways and immune status were significantly different between the 2 divided risk groups. Conclusions: The novel prognostic model composed of 9 ferroptosis-related genes accurately predicts the survival of BRCA patients. It might provide a new sight for ferroptosis-related BRCA therapy.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(1): 1-5, 2003 Feb.
Artículo en Chino | MEDLINE | ID: mdl-12939953

RESUMEN

This paper investigates the direct upconversion sensitization luminescence of the ErYb co-doped oxyfluoride glass (ErYb: FOG), fluoride glass (ErYb: ZBLAN) and pentaphosphate noncrystalline (ErYb: PP) excited by a 966 nm diode laser. The splendid upconversion luminescence phenomenon is found. It is resulted from that the Yb3+ concentration in rather high, the energy transfer among Er(3+)-Yb3+ and Yb(3+)-Yb3+ ions is rather strong. An important fact is found that the direct upconversion sensitization luminescence of ErYb: FOG is about 100-100,000 times greater than that of ErYb: PP. And meanwhile it is interesting that the upconversion luminescence intensity of ErYb: FOG is near to that of ErYb: ZBLAN. It is significant to enhance the comprehensive level of up-conversion luminescence.


Asunto(s)
Erbio/química , Luminiscencia , Iterbio/química , Transferencia de Energía , Fluorescencia , Fluoruros/química , Flúor/química , Vidrio/química , Óxidos/química , Fosfatos/química , Fotoquímica/métodos , Semiconductores , Análisis Espectral/métodos
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