Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-38178684

RESUMO

BACKGROUND: Yishan formula (YSF) has a significant effect on the treatment of breast cancer, which can improve the quality of life and prolong the survival of patients with breast cancer; however, its mechanism of action is unknown. OBJECTIVE: In this study, network pharmacology and molecular docking methods have been used to explore the potential pharmacological effects of the YSF, and the predicted targets have been validated by in vitro experiments. METHODS: Active components and targets of the YSF were obtained from the TCMSP and Swiss target prediction website. Four databases, namely GeneCards, OMIM, TTD, and DisGeNET, were used to search for disease targets. The Cytoscape v3.9.0 software was utilized to draw the network of drug-component-target and selected core targets. DAVID database was used to analyze the biological functions and pathways of key targets. Finally, molecular docking and in vitro experiments have been used to verify the hub genes. RESULTS: Through data collection from the database, 157 active components and 618 genes implicated in breast cancer were obtained and treated using the YSF. After screening, the main active components (kaempferol, quercetin, isorhamnetin, dinatin, luteolin, and tamarixetin) and key genes (AKT1, TP53, TNF, IL6, EGFR, SRC, VEGFA, STAT3, MAPK3, and JUN) were obtained. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis indicated that the YSF could affect the progression of breast cancer by regulating biological processes, such as signal transduction, cell proliferation and apoptosis, protein phosphorylation, as well as PI3K-Akt, Rap1, MAPK, FOXO, HIF-1, and other related signaling pathways. Molecular docking suggested that IL6 with isorhamnetin, MAPK3 with kaempferol, and EGFR with luteolin have strong binding energy. The experiment further verified that YSF can control the development of breast cancer by inhibiting the expression of the hub genes. CONCLUSION: This study showed that resistance to breast cancer may be achieved by the synergy of multiple active components, target genes, and signal pathways, which can provide new avenues for breast cancer-targeted therapy.

3.
Small ; 20(2): e2304311, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37697695

RESUMO

Due to the increased integration and miniaturization of electronic devices, traditional electronic packaging materials, such as epoxy resin (EP), cannot solve electromagnetic interference (EMI) in electronic devices. Thus, the development of multifunctional electronic packaging materials with superior electromagnetic wave absorption (EMA), high heat dissipation, and flame retardancy is critical for current demand. This study employs an in-situ growth method to load layered double hydroxides (LDH) onto transition metal carbides (MXene), synthesizing a novel composite material (MXene@LDH). MXene@LDH possesses a sandwich structure and exhibits excellent EMA performance, thermal conductivity, and flame retardancy. By adjusting the load of LDH, under the synergistic effect of multiple factors, such as dielectric and polarization losses, this work achieves an EMA material with a remarkable minimum reflection loss (RL) of -52.064 dB and a maximum effective absorption bandwidth (EAB) of 4.5 GHz. Furthermore, MXene@LDH emerges a bridging effect in EP, namely MXene@LDH/EP, leading to a 118.75% increase in thermal conductivity compared to EP. Simultaneously, MXene@LDH/EP contributes to the enhanced flame retardancy compared to EP, resulting in a 46.5% reduction in the total heat release (THR). In summary, this work provides a promising candidate advanced electronic packaging material for high-power density electronic packaging.

4.
Small ; 20(5): e2306248, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37759392

RESUMO

The Bi0.5 Sb1.5 Te3 (BST) thin film shows great promise in harvesting low-grade heat energy due to its excellent thermoelectric performance at room temperature. In order to further enhance its thermoelectric performance, specifically the power factor and output power, new approaches are highly desirable beyond the common "composition-structure-performance" paradigm. This study introduces ferroelectric polarization engineering as a novel strategy to achieve these goals. A Pb(Zr0.52 Ti0.48 )O3 /Bi0.5 Sb1.5 Te3 (PZT/BST) hybrid film is fabricated via magnetron sputtering. Density functional theory calculations demonstrate PZT polarization's influence on charge redistribution and interlayer charge transfer at the PZT/BST interface, facilitating adjustable carrier transport behavior and power factor of the BST film. As a result, a 26.7% enhancement of the power factor, from unpolarized 12.0 to 15.2 µW cm-1 K-2 , is reached by 2 kV out-of-plane downward polarization of PZT. Furthermore, a five-leg generator constructed using this PZT/BST hybrid film exhibits a maximum output power density of 13.06 W m-2 at ΔT = 39 K, which is 20.8% higher than that of the unpolarized one (10.81 W m-2 ). The research presents a new approach to enhance thermoelectric thin films' power factor and output performance by introducing ferroelectric polarization engineering.

5.
Small ; : e2306786, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38061990

RESUMO

There is increasing demand to power Internet of Things devices using ambient energy sources. Flexible, low-temperature, organic/inorganic thermoelectric devices are a breakthrough next-generation approach to meet this challenge. However, these systems suffer from poor performance and expensive processing preventing wide application of the technology. In this study, by combining a ferroelectric polymer (Polyvinylidene fluoride (PVDF, ß phase)) with p-type Bi0.5 Sb1.5 Te3 (BST) a thermoelectric composite film with maximum is produced power factor. Energy filter from ferroelectric-thermoelectric junction also leads to high Seebeck voltage ≈242 µV K-1 . For the first time, compelling evidence is provided that the dipole of a ferroelectric material is helping decouple electron transport related to carrier mobility and the Seebeck coefficient, to provide 5× or more improvement in thermoelectric power factor. The best composition, PVDF/BST film with BST 95 wt.% has a power factor of 712 µW•m-1  K-2 . A thermoelectric generator fabricated from a PVDF/BST film demonstrated Pmax T 12.02 µW and Pdensity 40.8 W m-2 under 50 K temperature difference. This development also provides a new insight into a physical technique, applicable to both flexible and non-flexible thermoelectrics, to obtain comprehensive thermoelectric performance.

6.
ACS Appl Mater Interfaces ; 15(42): 49259-49269, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37830755

RESUMO

The thermoelectric performance of n-type Bi2Te3 needs further enhancement to match that of its p-type Bi2Te3 counterpart and should be considered for competitive applications. Combining Cu/Cl and multiscale additives (AgBiSe2) presents a suitable route for such enhancement. This is evidence of the enhanced thermoelectric performance of Bi1.995Cu0.005Te2.69Se0.33Cl0.03. Moreover, by incorporating 0.65 wt % AgBiSe2 (ABS) into Bi1.995Cu0.005Te2.69Se0.33Cl0.03, we further reduce its lattice thermal conductivity to ∼0.28 W m-1 K-1 at 353 K owing to the extra phonon scattering of multiscale ABS. Additionally, the Seebeck coefficient enhances (-183.89 µV K-1 at 353 K) owing to the matrix's reduced carrier concentration caused by ABS. As a result, we achieve a high ZT of ∼1.25 (at 353 K) and a high ZTave of ∼1.12 at 300-433 K for Bi1.995Cu0.005Te2.69Se0.33Cl0.03 + 0.65 wt % ABS. This work provides a promising strategy for enhancing the thermoelectric performance of n-type Bi2Te3 through Cu/Cl doping and ABS incorporation.

7.
Org Lett ; 25(23): 4252-4257, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37265105

RESUMO

An efficient electrochemical dehydrogenative cross-coupling of benzylic C-H bonds with 1-thiosugars at room temperature is described. The direct S-glycosylation protocol avoids using any oxidant, which provides facile access to various glycosylated xanthene derivatives with up to 91% yield. This current electrooxidative reaction is characterized by high atom economy, high efficiency, mild reaction conditions, being environmentally benign, and excellent functional group tolerance. Moreover, preliminary mechanistic investigations reveal that the reaction involves a free radical process.


Assuntos
Tioaçúcares , Glicosilação , Tolerância a Medicamentos , Oxidantes , Xantenos
8.
Small ; 19(29): e2301963, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37178393

RESUMO

Cu2 SnS3 is a promising thermoelectric candidate for power generation at medium temperature due to its low-cost and environmental-benign features. However, the high electrical resistivity due to low hole concentration severely restricts its final thermoelectric performance. Here, analog alloying with CuInSe2 is first adopted to optimize the electrical resistivity by promoting the formation of Sn vacancies and the precipitation of In, and optimize lattice thermal conductivity through the formation of stacking faults and nanotwins. Such analog alloying enables a greatly enhanced power factor of 8.03 µW cm-1 K-2 and a largely reduced lattice thermal conductivity of 0.38 W m-1  K-1 for Cu2 SnS3 - 9 mol.% CuInSe2 . Eventually, a peak ZT as high as 1.14 at 773 K is achieved for Cu2 SnS3 - 9 mol.% CuInSe2 , which is one of the highest ZT among the researches on Cu2 SnS3 -based thermoelectric materials. The work implies analog alloying with CuInSe2 is a very effective route to unleash superior thermoelectric performance of Cu2 SnS3 .

9.
Medicine (Baltimore) ; 102(13): e33384, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37000102

RESUMO

BACKGROUND: Lung adenocarcinoma (LUAD) is the main pathological type of lung cancer. Qishan formula (QSF) is reportedly efficacious against LUAD. However, its mechanisms of action currently remain elusive. Therefore, network pharmacology, molecular docking techniques and proteomics were used to verify the potential pharmacological effects of QSF in the treatment of LUAD. METHODS: The active ingredients and potential targets of QSF were obtained from the TCMSP, chemical source network and construct a drug-component-target networks using Cytoscape v3.7.2. Data for disease targets were obtained from 5 databases: TCGA, OMIM, DrugBank, DisGeNET, and GeneCards. Drug disease cross targets were used to construct protein-protein interaction networks for selecting the core targets using the STRING database and enrichment pathway networks using the DAVID database. Finally, TMT quantitative proteomics was used to identify the possible core targets and action pathways. Molecular docking to verify the affinity between components and targets. RESULTS: Network pharmacology identified core components of QSF against LUAD included baicalein, methylophiopogonone B, quercetin, kaempferol, isorhamnetin, and luteolin, which can act on 10 key targets (SRC, TP53, PIK3R1, MAPK3, STAT3, MAKP1, HSP90AA1, PIK3CA, HRAS, and AKT1). QSF might play a therapeutic role in LUAD by regulating biological processes such as signal transduction, protein phosphorylation, cell proliferation, and apoptosis, as well as the PI3K/AKT, MAPK, FoxO, and other signaling pathways. Proteomics identified 207 differentially expressed proteins, and by integrating with network pharmacology and molecular docking results we found that 6 core components of QSF may target TP53 against LUAD through the PI3K/AKT signaling pathway. CONCLUSION: QSF is a multitarget recipe potentially exerting pleiotropic effects in LUAD.


Assuntos
Adenocarcinoma de Pulmão , Medicamentos de Ervas Chinesas , Neoplasias Pulmonares , Humanos , Simulação de Acoplamento Molecular , Farmacologia em Rede , Fosfatidilinositol 3-Quinases , Proteômica , Proteínas Proto-Oncogênicas c-akt , Adenocarcinoma de Pulmão/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico
10.
ACS Appl Mater Interfaces ; 14(49): 54803-54811, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36459084

RESUMO

Bismuth telluride-based (Bi2Te3) alloys have long been considered the best thermoelectric (TE) materials at room temperature. However, the n-type Bi2Te3 alloys always exhibit poor thermoelectric performance than their p-type counterpart, which severely limits the energy conversion efficiency of thermoelectric devices. Here, we demonstrate that incorporating AgBiSe2 can concurrently regulate the electrical and thermal transport properties as well as improve the mechanical performance of n-type Bi2Te2.69Se0.33Cl0.03 for high thermoelectric performance. Among these, AgBiSe2 effectively enhanced the Seebeck coefficients of n-type Bi2Te2.69Se0.33Cl0.03 due to the reduced carrier concentration and reduced the thermal conductivity of n-type Bi2Te2.69Se0.33Cl0.03 owing to the enhanced phonon scattering by AgBiSe2 as well as its low thermal conductivity nature. Consequently, the simultaneous optimization of electrical and thermal transport properties enables us to achieve a maximum ZT of ∼1.21 (at ∼353 K) and an average ZTave of ∼1.07 (300-433 K) for 3.5 wt % AgBiSe2-incorporated Bi2Te2.69Se0.33Cl0.03, which are ∼25.62 and ∼23.36% larger than those of Bi2Te2.69Se0.33Cl0.03, respectively. This work proves that the incorporation of AgBiSe2 is an efficient way to improve the thermoelectric performance of bismuth telluride-based materials.

11.
Small ; 18(46): e2204303, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36228102

RESUMO

The sharp reduction in size and increase in power density of next-generation integrated circuits lead to electromagnetic interference and heat failure being a key roadblock for their widespread applications in polymer-based electronic packaging materials. This work demonstrates a multifunctional epoxy-based composite (MDCF@LDH/EP) with high electromagnetic wave (EMW) absorption, thermal conductivity, and flame retardancy performance. In which, the synergistic effect of porous structure and heterointerface promotes the multiple reflection and absorption, and dielectric loss of EMW. A low reflection loss of -57.77 dB, and an effective absorption bandwidth of 7.20 GHz are achieved under the fillings of only 10 wt%. Meanwhile, a 241.4% enhanced thermal conductivity of EP is due to the high continuous 3D melamine-derived carbon foams (MDCF), which provides a broad path for the transport of phonons. In addition, MDCF@LDH/EP composite exhibits high thermal stability and flame retardancy, thanks to the physical barrier effect of MDCF@LDH combined with the high temperature cooling properties of NiAl-LDH-CO3 2- . Compared with pure epoxy resin, the peak heat release rate and the total heat release rate are reduced by 19.4% and 30.7%, respectively. Such an excellent comprehensive performance enables MDCF@LDH/EP to a promising electronic packaging material.

12.
Theranostics ; 12(14): 6395-6408, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36168616

RESUMO

Rationale: The overall clinical response to FGFR inhibitor (FGFRi) is far from satisfactory in cancer patients stratified by FGFR aberration, the current biomarker in clinical practice. A novel biomarker to evaluate the therapeutic response to FGFRi in a non-invasive and dynamic manner is thus greatly desired. Methods: Six FGFR-aberrant cancer cell lines were used, including four FGFRi-sensitive ones (NCI-H1581, NCI-H716, RT112 and Hep3B) and two FGFRi-resistant ones (primary for NCI-H2444 and acquired for NCI-H1581/AR). Cell viability and tumor xenograft growth analyses were performed to evaluate FGFRi sensitivities, accompanied by corresponding 18F-fluorodeoxyglucose (18F-FDG) uptake assay. mTOR/PLCγ/MEK-ERK signaling blockade by specific inhibitors or siRNAs was applied to determine the regulation mechanism. Results: FGFR inhibition decreased the in vitro accumulation of 18F-FDG only in four FGFRi-sensitive cell lines, but in neither of FGFRi-resistant ones. We then demonstrated that FGFRi-induced transcriptional downregulation of hexokinase 2 (HK2), a key factor of glucose metabolism and FDG trapping, via mTOR pathway leading to this decrease. Moreover, 18F-FDG PET imaging successfully differentiated the FGFRi-sensitive tumor xenografts from primary or acquired resistant ones by the tumor 18F-FDG accumulation change upon FGFRi treatment. Of note, both 18F-FDG tumor accumulation and HK2 expression could respond the administration/withdrawal of FGFRi in NCI-H1581 xenografts correspondingly. Conclusion: The novel association between the molecular mechanism (FGFR/mTOR/HK2 axis) and radiological phenotype (18F-FDG PET uptake) of FGFR-targeted therapy was demonstrated in multiple preclinical models. The adoption of 18F-FDG PET biomarker-based imaging strategy to assess response/resistance to FGFR inhibition may benefit treatment selection for cancer patients.


Assuntos
Fluordesoxiglucose F18 , Neoplasias , Biomarcadores , Linhagem Celular Tumoral , Fluordesoxiglucose F18/metabolismo , Glucose/metabolismo , Hexoquinase , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Tomografia por Emissão de Pósitrons , Inibidores de Proteínas Quinases/farmacologia , Serina-Treonina Quinases TOR
13.
ACS Appl Mater Interfaces ; 14(32): 37204-37212, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35917399

RESUMO

An increasing number of studies have reported producing composite structures by combining thermoelectric and functional materials. However, combining energy filtering and ferroelectric polarization to enhance the dimensionless figure of merit thermoelectric ZT remains elusive. Here we report a composite that contains nanostructured BaTiO3 embedded in a Bi0.5Sb1.5Te3 matrix. We show that ferroelectric BaTiO3 particles are evenly composited with Bi0.5Sb1.5Te3 grains reducing the concentration of free charge carriers with increasing BaTiO3 content. Additionally, as a result of the energy-filtering effect and ferroelectric polarization, the Seebeck coefficient was improved by ∼10% with a ∼10% improvement in power factors. The BaTiO3 phase can effectively scatters phonons reducing lattice thermal conductivity κl (0.5 W m-1 K-1) and increasing ZT to 1.31 at 363 K in Bi0.5Sb1.5Te3 composites with 2 vol % BaTiO3 content giving an improvement of ∼25% over pure Bi0.5Sb1.5Te3. Our work indicates that the introduction of ferroelectric nanoparticles is an effective method for optimizing the ZT of Bi0.5Sb1.5Te3-based thermoelectric materials.

14.
J Colloid Interface Sci ; 628(Pt A): 696-704, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35944300

RESUMO

The severe non-radiative recombination loss caused by SnO2/perovskite interface defects greatly hinders the further improvement of the performance and stability of flexible perovskite solar cells (PSCs). Herein, a series of halides KM (M = F, Cl, Br, I) were inserted as interface layers to modulate the SnO2/perovskite interface. Both experimental and theoretical calculation demonstrated that F- exhibited stronger interface coupling effect between the SnO2 and perovskite than other halide ions (Cl-, Br-, I-). The F- had unique effects in effectively depressing SnO2/perovskite interface defects ascribed to the simultaneous formation of SnF bonds and hydrogen bonds, resulting in reduced non-radiative recombination and improved interfacial contact. In consequence, the champion KF-modified flexible and rigid PSCs delivered outstanding PCE of 18.16 % and 21.36 %, accompanied by the enhanced VOC of 1.14 V and 1.16 V, respectively. Meanwhile, the stability of flexible PSCs was significantly ameliorated after KF modification, and about 84 % of the original efficiency could be retained even after 3000 bending cycles. This work provides a facile and efficient strategy for interface modulation to achieve high-performance and stable flexible PSCs.

15.
ACS Appl Mater Interfaces ; 14(7): 9192-9202, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35133800

RESUMO

A nanostructure has a significant role in enhancing the power factor and preventing the heat propagation for thermoelectric materials. Herein, we propose a unique segregated and percolated (SP) microphase-separated structure to enhance the thermoelectric performance of SnTe. The SP structure is composed of insoluble SnTe and AgCuTe, in which AgCuTe with ultralow lattice thermal conductivity undergoes a solid-phase welding during a spark plasma sintering process and forms continuous percolated layers at the interface of isolated SnTe. The SP structure achieved a simultaneous scattering for low energy holes due to the energy offset of the valence band maximum between SnTe and AgCuTe and for phonons due to the noncoherent interfaces between SnTe and AgCuTe, resulting in a high Seebeck coefficient of ∼219.4 µV/K and a low lattice thermal conductivity of ∼1.1 W m-1 K-1 at 800 K for (SnTe)0.55(AgCuTe)0.45. The thermoelectric performance was further enhanced by means of the cosubstitution of In and Mn for Sn in the SnTe lattice, inducing resonance levels and extra phonon scattering. As a result, the SP structure combined with In/Mn codoping enable us to achieve a low lattice thermal conductivity of 0.47 W m-1 K-1, a peak ZT of ∼1.45 at 800 K, and a high average ZT of ∼0.73 (400-800 K) for (Sn0.98In0.01Mn0.01Te)0.75(AgCuTe)0.25.

16.
ACS Appl Mater Interfaces ; 14(6): 7962-7971, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35119820

RESUMO

Tin oxide (SnO2) has been commonly used as an electron transport layer (ETL) in planar perovskite solar cells (p-PSCs) because it can be prepared by a low-temperature solution-processed method. However, the device performance has been restricted due to the limited electrical performance of SnO2 and its mismatched energy level alignment with the perovskite absorber. Considering these problems, sodium tungstate (Na2WO4) has been employed to modify the SnO2 ETL. The conduction band minimum of SnO2 increases and the defects at the ETL/perovskite interface decrease by the modification of the SnO2 ETL with Na2WO4, thus reducing the energy barrier between the ETL and perovskite. In addition, the electron extraction ability has been enhanced and the interface recombination between the ETL and perovskite has also been inhibited. As a result, the photovoltaic performance of p-PSCs based on the modified ETL has been improved, and a champion power conversion efficiency of 21.16% has been achieved compared with the control device of 17.30% with an open circuit voltage increased from 1.075 to 1.162 V.

17.
ACS Appl Mater Interfaces ; 13(45): 53492-53503, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34726054

RESUMO

In this spotlight on applications, we describe our recent progress on the terahertz (THz) characterization of linear and nonlinear dielectrics for broadening their applications in different electrical devices. We begin with a discussion on the behavior of dielectrics over a broadband of frequencies and describe the main characteristics of ferroelectrics, as they are an important category of nonlinear dielectrics. We then move on to look at the influence of point defects, porosities, and interfaces, including grain boundaries and domain walls, on the dielectric properties at THz frequencies. Based on our studies on linear dielectrics, we show that THz characterization is able to probe the effect of porosities, point defects, shear planes, and grain boundaries to improve dielectric properties for telecommunication applications. Further, we demonstrate that THz measurements on relaxor ferroelectrics can be successfully used to study the reversibility of the electric field-induced phase transitions, providing guidance for improving their energy storage efficiency in capacitors. Finally, we show that THz characterization can be used to characterize the effect of domain walls in ferroelectrics. In particular, our studies indicate that the dipoles located within domain walls provide a lower contribution to the permittivity at THz frequencies than the dipoles present in domains. The new findings could help develop a new memory device based on nondestructive reading operations using a THz beam.

18.
J Am Chem Soc ; 143(34): 13990-13998, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34410126

RESUMO

The reaction of MnTe with AgSbTe2 in an equimolar ratio (ATMS) provides a new semiconductor, AgMnSbTe3. AgMnSbTe3 crystallizes in an average rock-salt NaCl structure with Ag, Mn, and Sb cations statistically occupying the Na sites. AgMnSbTe3 is a p-type semiconductor with a narrow optical band gap of ∼0.36 eV. A pair distribution function analysis indicates that local distortions are associated with the location of the Ag atoms in the lattice. Density functional theory calculations suggest a specific electronic band structure with multi-peak valence band maxima prone to energy convergence. In addition, Ag2Te nanograins precipitate at grain boundaries of AgMnSbTe3. The energy offset of the valence band edge between AgMnSbTe3 and Ag2Te is ∼0.05 eV, which implies that Ag2Te precipitates exhibit a negligible effect on the hole transmission. As a result, ATMS exhibits a high power factor of ∼12.2 µW cm-1 K-2 at 823 K, ultralow lattice thermal conductivity of ∼0.34 W m-1 K-1 (823 K), high peak ZT of ∼1.46 at 823 K, and high average ZT of ∼0.87 in the temperature range of 400-823 K.

19.
J Pharmacol Exp Ther ; 379(2): 125-133, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34373354

RESUMO

The pharmaceutical industry and clinical trials have been revolutionized mesenchymal stem cell-based therapeutics. However, the pharmacokinetics of transplanted cells has been little characterized in their target tissues under healthy or disease condition. A quantitative polymerase chain reaction analytical method with matrix effect was developed to track the biodistribution of human mesenchymal stem cells in normal mice and those with Concanavalin A (Con A)-induced liver injury. Mesenchymal stem/stromal cell (MSC) disposition in blood and different organs were compared, and relevant pharmacokinetic parameters were calculated. Human MSCs (hMSCs) and mouse MSCs (mMSCs) displayed a very similar pharmacokinetic profile in all tested doses: about 95% of the detected hMSCs accumulated in the lung and 3% in the liver, and almost negligible cells were detected in other tissues. A significant double peak of hMSC concentration emerged in the lung within 1-2 hours after intravenous injection, as with mMSCs. Prazosin, a vasodilator, could eliminate the second peak in the lung and increase its Cmax and area under the concentration-time curve (AUC) by 10% in the first 2 hours. The injury caused by Con A was significantly reduced by hMSCs, and the Cmax and AUC0-8 (AUC from time 0 to 8 hours) of cells in the injured liver decreased by 54 and 50%, respectively. The Cmax and AUC would be improved with the alleviation of congestion through the administration of heparin. The study provides a novel insight into the pharmacokinetics of exogenous MSCs in normal and Con A-induced liver injury mice, which provides a framework for optimizing cell transplantation. SIGNIFICANCE STATEMENT: Mesenchymal stem/stromal cells (MSCs) are known for their potential as regenerative therapies in treating several diseases, but an insufficient understanding of the pharmacokinetics of MSCs restricts their future application. The current study was the first to elucidate the pharmacokinetics and possible factors, including dosage, species, and derived sources, in a systematic way. The study further revealed that Concanavalin A-induced liver injury significantly prevented cells from entering the injury site, which could be reversed by the diminished congestion achieved by heparin.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/terapia , Concanavalina A/toxicidade , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Mitógenos/toxicidade , Animais , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
20.
ACS Appl Mater Interfaces ; 13(31): 37027-37034, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34323074

RESUMO

The lead-free double perovskite has been proven to be one of the promising alternatives to solve the stability and toxicity problems of lead-based organic-inorganic hybrid perovskite solar cells. Here, high-quality Cs2AgBiBr6 double perovskite films with large grains and smooth surface have been prepared through a sequential-vapor-deposition method, and a low-cost and eco-friendly Cu2O film with a suitable energy level and good electrical properties was prepared as an efficient hole transport layer by vacuum vapor deposition for the first time. The Cu2O-based devices achieve a champion power conversion efficiency increasing from 1.03 to 1.52% and an enhancement of photovoltage from 1.083 to 1.198 V compared with their organic counterparts. More importantly, the Cu2O-based devices have excellent stability; they maintained the initial 96% efficiency under environmental conditions after 33 days of unpackaged storage. These results also point out the direction for the further development of these new promising perovskite solar cells.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA