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1.
Bioorg Med Chem Lett ; 64: 128680, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35306167

RESUMO

Aberrantly activated Janus kinase 3 (JAK3) has been constantly detected in various immune disorders and hematopoietic cancers, suggesting its potential of being an attractive therapeutic target for these indications. Clinical benefits of drugs selectively targeting JAK3 versus pan-JAK inhibitors remain unclear. In this study, we report the design and synthesis of a new series of JAK3 covalent inhibitors with a pyrido[2,3-d]pyrimidin-7-one scaffold. After the extensive SAR study, compound 10f emerged to be the most potent JAK3 inhibitor with an IC50 value of 2.0 nM. It showed excellent selectively proliferation inhibitory activity against U937 cells harboring JAK3 M511I mutation, while remained weakly active to the other tested cancer cells. Compound 10f also dose-dependently inhibited the phosphorylation of JAK3 and its downstream signal STAT5 in U937 cells. Taken together, 10f may serve as a promising tool molecule for treating cancers with aberrantly activated JAK3.


Assuntos
Janus Quinase 3 , Inibidores de Proteínas Quinases , Janus Quinase 1 , Janus Quinase 2 , Janus Quinase 3/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Relação Estrutura-Atividade
2.
Sci Total Environ ; 825: 153894, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35182628

RESUMO

Evaluation of the nitrate transport process in the deep vadose zone (DVZ) is important for groundwater quality management, especially in intensive agricultural regions, such as the North China Plain (NCP). The NCP produces ~20% of the total food grain in China, owing to timely groundwater irrigation and excessive chemical N fertilizer applications, and faces severe groundwater environmental degradation. This study evaluated the potential impacts of intensive agriculture on groundwater quality by investigating nitrate accumulation and transport in the DVZ of wheat-maize double-cropping field based on sediment sampling (maximum depth of 45.2 m) over three sub-regions of the NCP. The results showed that legacy nitrate­nitrogen (NO3--N) accumulated in the DVZ ranged from 118.5 to 6302.8 kg N ha-1 across the NCP; it increased with depth at an average rate of ~157 kg ha-1 m-1. Nitrate transport and accumulation in the DVZ were spatially varied and mainly controlled by the DVZ sediment textures, in addition to water and nitrogen inputs from the ground surface. Coarse sediments retained lower soil water content, resulting in less nitrogen storage; however, they provided greater nitrate transport velocity. Higher transport velocities observed in the alluvial-proluvial fan allowed chemical N fertilizer to reach the water table. However, in other regions, nitrate transport velocities were lower than the water table decline rates, implying that groundwater quality may not have been impaired by chemical N fertilizer. Furthermore, a reductive environment was identified in some areas with fine sediments, indicating a favorable environment for denitrification in the DVZ. The findings of the current study could provide an important foundation for groundwater quality management in agricultural areas, such as the NCP and similar regions.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Agricultura , China , Monitoramento Ambiental , Fertilizantes , Água Subterrânea/química , Nitratos/análise , Nitrogênio/análise , Água , Poluentes Químicos da Água/análise
3.
Int J Biol Macromol ; 194: 1029-1037, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34856214

RESUMO

In this work, a simple but effective method based on Gamma-ray initiated polymerization was reported for the first time through direct irradiation of CNCs and ionic liquid monomer to obtain poly (ionic liquids) functionalized CNCs (IL@CNCs). The adsorptive removal of Congo red (CR) from aqueous solution by IL@CNCs was also examined and the influence of contact time, pH values, initial concentrations and temperature on adsorption behavior was investigated in detail. Under the same adsorption conditions, the adsorption capacity was increased from 59.72 mg/g (CNCs) to 195.83 mg/g (IL@CNCs). The results of the adsorption isotherm and adsorption kinetics showed that the experimental data were more suitable to be described by the Freundlich isotherm adsorption model and the pseudo-second-order model. The adsorption process of CR on the surface of the adsorbent was endothermic and spontaneous. When the aqueous solution was acidic, it was more conducive to the adsorption of CR. At 100% breakthrough, the value of adsorption capacity is 199.95 mg/g and the value of partition coefficient is 9.64. Moreover, the adsorption capacity is expected to be further improved through adjustment of polymerization parameters and this method can also be used for preparation other poly (ionic liquids) modified composites.


Assuntos
Celulose/química , Vermelho Congo/química , Raios gama , Líquidos Iônicos/química , Nanopartículas/química , Polímeros/química , Adsorção , Concentração de Íons de Hidrogênio , Polimerização , Análise Espectral , Termogravimetria , Poluentes da Água , Purificação da Água
5.
ACS Appl Mater Interfaces ; 13(49): 59164-59173, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34851097

RESUMO

Near-infrared window II (NIR-II, 1000-1700 nm) imaging displays the advantages in deep-tissue high-contrast imaging in vivo on the strength of the high temporal-spatial resolution and deeper penetration. However, the clinical utility of NIR-II imaging agents is limited by their single function. Herein, for the first time, we report the design of a multifunctional drug delivery system (DDS) assembly, CQ/Nd-MOF@HA nanohybrids, with NIR-II fluorescence (1067 nm), large Stokes shifts, and ultrahigh quantum yield, which combined targeted NIR-II luminescence bioimaging and pH-controlled drug delivery. The nanoscale metal-organic framework (MOF) as a highly promising multifunctional DDS for targeted NIR-II bioimaging and chemotherapy in vitro and in vivo lays the foundation of the MOF-based DDS for further clinical diagnosis and treatment.


Assuntos
Antineoplásicos/farmacologia , Ácido Hialurônico/farmacologia , Estruturas Metalorgânicas/farmacologia , Neodímio/farmacologia , Imagem Óptica , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/tratamento farmacológico , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Ácido Hialurônico/química , Concentração de Íons de Hidrogênio , Raios Infravermelhos , Masculino , Teste de Materiais , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/química , Camundongos , Camundongos Endogâmicos BALB C , Neodímio/química , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/tratamento farmacológico , Tamanho da Partícula , Propriedades de Superfície , Células Tumorais Cultivadas
6.
Hu Li Za Zhi ; 68(6): 32-42, 2021 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-34839489

RESUMO

BACKGROUND: Hospice shared care is a model of care widely used in patients with terminal cancer. Appropriate interventions to improve related symptoms should be provided during disease progression through the end of life. PURPOSE: The purpose of this study was to explore the related symptoms and to compare symptom severity before and after the implementation of hospice shared care and medical care interventions. METHODS: Fifty patients with terminal cancer were enrolled in this longitudinal, quasi-experimental research. Inclusion criteria included having an expected life span of < 6 months and agreeing to enter hospice shared care. RESULTS: The three most-frequently noted physical symptoms were, in rank order: "pain", "weakness", and "dyspnea". In terms of severity, "pain" was the most severe, followed by "weakness" and "disturbance of sleep". The three most-frequently noted psychological symptoms were, in rank order: "depression", "worry about the disease", and "afraid of dragging others down". In terms of severity, "depression" was the most severe, followed by "anxiety" and "worry about the disease". The frequency and severity of the top-3 social and spiritual distress symptoms were, in rank order: "unfinished wish", "economic difficulties", and "painlessness". During the study period, the severity of physical symptoms improved gradually, while the severity of psychological symptoms improved significantly. The top-3 items in the original medical team`s hospice-care interventions were, in rank order: "tube care", "laboratory test", and "wound care" in the non-pharmacological category; "symptom control medication", "antibiotic injection", and "intravenous fluid infusion" in the pharmacological category; and "cognitive clarification of the prognosis condition", "do not conduct resuscitation discussions and signing", and "emotional stress consoling" in the problem-coordination and interview categories. The interventions implemented by the hospice specialist team included "emotional stress interview", "team communication", and "cognitive clarification of prognosis condition" in the problem coordination and interview categories, and "massage", "consultation", and "nursing advice" in the non-pharmacological category. CONCLUSIONS / IMPLICATIONS FOR PRACTICE: The symptoms identified in this study provide clinical staff with a reference for the rapid assessment of patients with terminal-stage cancer. Manpower from various professional fields are committed to providing diversified services in the care teams, which positively affect the control of related symptoms. The experience presented in this article may be used as a reference to promote the hospice shared care model.


Assuntos
Cuidados Paliativos na Terminalidade da Vida , Hospitais para Doentes Terminais , Neoplasias , Assistência Terminal , Ansiedade , Humanos , Massagem , Neoplasias/terapia
7.
Diagnostics (Basel) ; 11(9)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34573925

RESUMO

Mucopolysaccharidoses (MPSs) are a group of lysosomal storage diseases (LSDs) caused by an inherited gene defect. MPS patients can remain undetected unless the initial signs or symptoms have been identified. Newborn screening (NBS) programs for MPSs have been implemented in Taiwan since 2015, and more than 48.5% of confirmed cases of MPS have since been referred from these NBS programs. The purpose of this study was to report the current status of NBS for MPSs in Taiwan and update the gold standard criteria required to make a confirmative diagnosis of MPS, which requires the presence of the following three laboratory findings: (1) elevation of individual urinary glycosaminoglycan (GAG)-derived disaccharides detected by MS/MS-based assay; (2) deficient activity of a particular leukocyte enzyme by fluorometric assay; and (3) verification of heterogeneous or homogeneous variants by Sanger sequencing or next generation sequencing. Up to 30 April 2021, 599,962 newborn babies have been screened through the NBS programs for MPS type I, II, VI, and IVA, and a total of 255 infants have been referred to MacKay Memorial Hospital for a confirmatory diagnosis. Of these infants, four cases were confirmed to have MPS I, nine cases MPS II, and three cases MPS IVA, with prevalence rates of 0.67, 2.92, and 4.13 per 100,000 live births, respectively. Intensive long-term regular physical and laboratory examinations for asymptomatic infants with confirmed MPS or with highly suspected MPS can enhance the ability to administer ERT in a timely fashion.

8.
Dalton Trans ; 50(39): 13877-13882, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34523647

RESUMO

Metal-organic frameworks (MOFs) emerging as a type of functional material have been widely used in electrochemical energy storage and conversion in recent years. Hollow MOFs with a large pore volume and surface area can increase the contact area between active materials and electrolytes, thus improving the ionic conductivity of the materials. Herein, we obtained a kind of hollow MOF (ZIF-8) using carboxylate-terminated polystyrene microspheres as exterior templates. Transmission electron microscopy and N2 adsorption/desorption analysis revealed that the average cavity diameter of hollow ZIF-8 is 1 µm. Moreover, hollow ZIF-8 exhibits excellent electrochemical quality with an ionic conductivity of 7.36 × 10-4 S cm-1, a lithium ion transference number of 0.83 and an activation energy of 0.15 eV in a wide stable electrochemical window of 2.0-6.5 V at room temperature. Compared with the traditional non-hollow ZIF-8, the electrochemical performance has been improved obviously. Consequently, our strategy of fabrication of large pore volume hollow MOFs provides a new perspective for the development of solid electrolytes with excellent lithium ionic conductivity.

9.
J Hazard Mater ; 420: 126580, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34252673

RESUMO

The adsorption applications of MXene-based adsorbents have intensively investigated recently. However, the performance of MXene-based adsorbents has been largely limited owing to their lack of functional groups and adsorptive sites. Therefore, surface functionalization of MXene is an important route to achieve better performance for environmental adsorption. Herein, polyionic liquid functionalized MXene (named as MXene-PIL) was prepared through a multi-component reaction and adsorptive removal of iodine by MXene-PIL was also evaluated. The successful generation of PIL on MXene was confirmed by a series of characterization measurements. Furthermore, the effects of contact time, iodine concentration, environmental temperature and other factors on the adsorption performance of MXene-PIL were investigated. Adsorption kinetic analysis including pseudo-first-order dynamic model, pseudo-second-order dynamic model and Weber-Morris model, adsorption thermodynamic analysis such as Langmuir and Freundlich models and Van't Hoff equation were used for further analysis the adsorption behavior of iodine by MXene-PIL. We demonstrated that the adsorption capacity could be as high as about 170 mg/g, which is obviously larger than the unmodified MXene and most of other reported adsorbents. Taken together, a simple strategy has been developed for in-situ generation of PIL on MXene and the resultant composites show potential application for adsorptive removal of iodine.

10.
Int J Biol Macromol ; 186: 591-615, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34271046

RESUMO

Cellulose nanocrystals (CNCs) are a class of sustainable nanomaterials that are obtained from plants and microorganisms. These naturally derived nanomaterials are of abundant hydroxyl groups, well biocompatibility, low cost and biodegradable potential, making them suitable and promising candidates for various applications, especially in biomedical fields. In this review, the recent advances and development on the preparation, surface functionalization and biomedical applications of CNCs-based materials have been summarized and outlined. The main context of this paper could be divided into the following three parts. In the first part, the preparation strategies based on physical, chemical, enzymatic and combination techniques for preparation of CNCs have been summarized. The surface functionalization methods for synthesis CNCs-based materials with designed properties and functions were outlined in the following section. Finally, the current state about applications of CNCs-based materials for tissue engineering, medical hydrogels, biosensors, fluorescent imaging and intracellular delivery of biological agents have been highlighted. Moreover, current issues and future directions about the above aspects have also pointed out and discussed. We believe this review will attract great research attention of scientists from materials, chemistry, biomedicine and other disciplines. It will also provide some important insights on the future development of CNCs-based materials especially in biomedical fields.


Assuntos
Celulose/química , Nanopartículas , Nanotecnologia , Animais , Configuração de Carboidratos , Humanos , Relação Estrutura-Atividade , Propriedades de Superfície
11.
J Hazard Mater ; 419: 126220, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34323712

RESUMO

In this work, a novel imidazoles-MXene hybrid composite, namely polyimidazoles chain overlaying on the surface of MXene (Ti3C2@IMIZ), was prepared by a simple method. Through this strategy, imidazoles can be in situ growth on the surface of MXenes via a facile multicomponent reaction using chitosan as a renewable reactant. Based on the characterization results, we demonstrated that a thin layer imidazoles with an ordered chain structure was embedded on the surface of Ti3C2, which resulted in the formation of a novel imidazoles-MXene hybrid composite. The adsorption performance of Ti3C2@IMIZ for removal environmental pollutants was evaluated using heavy metal ions of Cr(Ⅵ) as adsorbate. Detailed adsorption characteristics of Ti3C2@IMIZ including operational factors, adsorption kinetics and isotherms models were investigated. XPS analysis showed that Cr(VI) was converted to Cr(III) with low toxicity during the adsorption process. The adsorption of Cr(VI) and reduction of Cr(VI) to Cr(III) contribute to elimination of Cr(VI) species. The adsorption behavior and process analysis show that the adsorption mechanism is mainly physical adsorption through electrostatic interaction. The excellent reproducibility suggests that Ti3C2@IMIZ may be a potential candidate for remove of Cr(Ⅵ) in actual sewage treatment.


Assuntos
Quitosana , Poluentes Químicos da Água , Adsorção , Cromo/análise , Concentração de Íons de Hidrogênio , Cinética , Reprodutibilidade dos Testes , Poluentes Químicos da Água/análise
12.
Int J Biol Macromol ; 182: 2066-2075, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34087297

RESUMO

Herein, a novel strategy for surface functionalization and drug loading of cellulose nanocrystals (CNCs) through formation of hydrazone bonds between functionalized CNCs and aldehyde group containing polyethylene glycol (CHO-PEG)/anticancer drug doxorubicin (DOX) was reported for the first time. DOX could be loaded on PEGylated CNCs with high capacity and released from drug complexes (P-CNCs-D) with pH dependent behavior. The biological evaluation results demonstrated that drug carriers (CNCs-EBO-NH) showed negative cytotoxicity while DOX could be transported into cells and exhibits desirable anticancer effects. As compared with other method, the method developed in this work is rather simple and effective and can be achieved for simultaneous for surface functionalization and drug loading in a one-pot route. This work will open a new avenue for fabrication of various multifunctional composites based on other carbohydrate polymers or materials and to explore their applications in biomedical fields.


Assuntos
Celulose/química , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos BALB C , Nanopartículas/ultraestrutura , Espectroscopia Fotoeletrônica , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Temperatura , Termogravimetria , Carga Tumoral/efeitos dos fármacos
13.
J Colloid Interface Sci ; 601: 294-304, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34082233

RESUMO

In this work, a highly efficient adsorbent based on ionic liquid functionalized MXene has been fabricated through the combination of mussel-inspired chemistry and Michael addition reaction. The surface of MXene was first coated with polydopamine (PDA) through self-polymerization of dopamine and the amino groups were introduced on the surface of MXene simultaneously. After that, the ene bond-containing ionic liquid was further immobilized on the surface of MXene-PDA to obtain MXene-PDA-IL. As a concept, the adsorptive removal of iodine using MXene-PDA-IL was conducted and the effects of various factors on the adsorption behavior were examined. The experimental data were analyzed by intermittent adsorption experiments, the adsorption kinetics, adsorption isotherm, adsorption thermodynamics, and cyclic adsorption experiments. We found that the adsorption procedure could reach equilibrium within 10 min after mixing adsorbent and iodine. The maximum adsorption capacity of MXene-PDA-IL towards iodine was as high as 695.4 mg g-1, which is greater than most of reported adsorbents. Considered the advantages of mussel-inspired chemistry for surface functionalization and the adsorption capacity of ionic liquids, the method could be used for construct a number of composites with potential for adsorption applications.


Assuntos
Iodo , Líquidos Iônicos , Poluentes Químicos da Água , Adsorção , Polimerização , Poluentes Químicos da Água/análise
14.
Sensors (Basel) ; 21(9)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33925177

RESUMO

This paper describes the multilayer voting algorithm, a novel autonomous star identification method for spacecraft attitude determination. The proposed algorithm includes two processes: an initial match process and a verification process. In the initial match process, a triangle voting scheme is used to acquire candidates of the detected stars, in which the triangle unit is adopted as the basic voting unit. During the identification process, feature extraction is implemented, and each triangle unit is described by its singular values. Then the singular values are used to search for candidates of the imaged triangle units, which further improve the efficiency and robustness of the algorithm. After the initial match step, a verification method is applied to eliminate incorrect candidates from the initial results and then outputting the final match results of the imaged stars. Experiments show that our algorithm has more robustness to position noise, magnitude noise, and false stars than the other three algorithms, the identification speed of our algorithm is largely faster than the geometric voting algorithm and optimized grid algorithm. However, it takes more memory, and SVD also seems faster.

15.
Langmuir ; 37(13): 3922-3928, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33760624

RESUMO

Metal-organic frameworks (MOFs), due to their possessing a porous structure, are potential candidates for solid-state ionic conduction materials. Moreover, uncoordinated carboxylic acid groups (-COOH) of MOFs can be used as postsynthetic modification sites, which are favorable for lithium ion exchange. Herein, we synthesized a unique multiple carboxylic zinc metal-organic framework (Zn-MOF-COOH) containing uncoordinated carboxylic acid groups. Zn-MOF-COOLi was synthesized through deprotonation using LiOH via a straightforward acid-base reaction at room temperature (RT), thereby exhibiting better good electrochemical properties. The lithium ionic conductivity (σ) increased from 1.81 × 10-5 to 1.65 × 10-4 S·cm-1, lithium ion transference number (tLi+) rose from 0.67 to 0.77, and the electrochemical window improved from 2.0-5.5 to 1.5-6.5 V. This work offers a new strategy to improve the σ of MOFs and a new perspective toward manufacturing of high-performance solid-state ionic conduction materials.

16.
Inorg Chem ; 60(7): 5282-5289, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33749274

RESUMO

Fluoroquinolone antibiotic (FQ) residues, such as ciprofloxacin (CIP) and ofloxacin (OFLX), have aroused public concerns owing to their serious impact in environmental water or food fields which influence human health. A facile and high-performance sensory method for detecting FQs is highly desirable for practical requirements. Herein, we have presented a luminescent Eu-MOF with unique 2D (4-c) {44.62}-connected topology, which holds the outstanding fluorescent property and excellent chemical stability in aqueous solution for 15 days. Thus, Eu-MOF can be considered as a highly sensitive chemo-sensor for sensing CIP and OFLX with different fluorescent color conversion (red changes to green for OFLX and to blue for CIP) and a low detection limit of 0.693 and 0.802 ppb, respectively. Furthermore, the mechanism of sensing CIP and OFLX was exposed to the photoinduced electron transfer (PET) and dynamic quenching process, as evaluated by DFT calculations and fluorescence lifetime decay measurements. Our work first reports a simple and efficient strategy for recognizing CIP and OFLX with a special luminescence color-change phenomenon based on MOF materials, serving as a meaningful guide for researchers in beneficial applications.


Assuntos
Antibacterianos/análise , Európio/química , Fluoroquinolonas/análise , Estruturas Metalorgânicas/química , Teoria da Densidade Funcional , Medições Luminescentes , Estruturas Metalorgânicas/síntese química
17.
Macromol Rapid Commun ; 42(6): e2000563, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33543565

RESUMO

As the core of polymer chemistry, manufacture of functional polymers is one of research hotspots over the past several decades. Various polymers are developed for diverse applications due to their tunable structures and unique properties. However, traditional step-by-step preparation strategies inevitably involve some problems, such as separation, purification, and time-consuming. The multicomponent reactions (MCRs) are emerging as environmentally benign synthetic strategies to construct multifunctional polymers or composites with pendant groups and designed structures because of their features, such as efficient, fast, green, and atom economy. This mini review summarizes the latest advances about fabrication of multifunctional fluorescent polymers or adsorptive polymeric composites through different MCRs, including Kabachnik-Fields reaction, Biginelli reaction, mercaptoacetic acid locking imine reaction, Debus-Radziszewski reaction, and Mannich reaction. The potential applications of these polymeric composites in biomedical and environmental remediation are also highlighted. It is expected that this mini-review will promote the development preparation and applications of functional polymers through MCRs.


Assuntos
Poluentes Ambientais , Nanopartículas , Iminas , Polímeros
18.
Chem Commun (Camb) ; 57(20): 2515-2518, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33555003

RESUMO

Metal-organic frameworks (MOFs) with polar space groups in crystallography represent a class of potential molecular-based ferroelectrics; however, the rational design and enhancement of the performance of MOF-based ferroelectrics is a great challenge. In this work, a series of mixed-metal MOFs deriving from Mg2+ ions doped into the lattice nodes of the parent-MOF (Ni-MOF) are synthesized by an in situ solvothermal method. Taking advantage of Mg2+ ions doped in the Ni-MOF, the doped-MOFs (Mg/Ni-MOFs) appear to have a significant lattice distortion and noteworthy dipole asymmetry in the crystals. It is found that the obtained doped-MOFs show a significant enhancement of ferroelectricity compared with that of the parent-MOF. This study opens up a new landscape to explore possibilities for controlling ferroelectric performance in MOF-based ferroelectrics.

19.
Exp Neurol ; 337: 113593, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33387462

RESUMO

Increasing evidence has demonstrated that the Nod-like receptor pyrin domain containing 3 (Nlrp3) inflammasome overactivated during demyelinating disorders. It has been implicated that transient receptor potential type 4 (Trpv4) is regarded as a polymodal ionotropic receptor that plays an important role in a multitude of pathological conditions, including inflammation. The aim of this study was to investigate whether the Trpv4 channel regulates Nlrp3 inflammasome in the corpus callosum of mice with demyelination. Our results showed that CPZ treatment significantly increased the expression of Trpv4, activated Nlrp3 inflammasome, reduced peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) and decreased mitochondrial function. siRNA-mediated Nlrp3 knockdown inhibited glial activation and alleviated demyelination. Whereas knockdown of Trpv4 by siRNA markedly ameliorated Nlrp3 inflammasome activation and restored mitochondrial function as well as reducing the level of reactive oxygen species (ROS). Meanwhile, glial activation, demyelination and behavioral impairment induced by CPZ were also alleviated by siRNA-mediated Trpv4 knockdown. Furthermore, immunoprecipitation and use of a lysine acetylation assay showed that Sirtuin1 (SIRT1) mediated the PGC-1α deacetylation, which is involved in Nlrp3 inflammasome activation. These findings suggest that Trpv4 regulates mitochondrial function through the SIRT1/PGC-1α pathway, which further trigger Nlrp3 inflammasome activation in the CPZ-induced demyelination in mice.


Assuntos
Doenças Desmielinizantes/genética , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Sirtuína 1/genética , Canais de Cátion TRPV/fisiologia , Animais , Quelantes , Transtornos Cognitivos/genética , Transtornos Cognitivos/psicologia , Corpo Caloso/patologia , Cuprizona , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/psicologia , Técnicas de Silenciamento de Genes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Neuroglia , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio
20.
Dalton Trans ; 49(31): 10895-10900, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32720661

RESUMO

Ferroelectrics as crucial functional materials have attracted much interest since ferroelectricity was discovered in 1920. Herein, an unusual high-frequency ferroelectric, (CH3)2NH·HCl@Cd-MOF, was successfully obtained through a dual-step synthetic methodology. A chiral porous Cd-MOF with a channel size of 6.8 × 6.8 Å was synthesized via self-assembly of chiral Schiff-base ligands and Cd2+ ions. Subsequently, polarizable (CH3)2NH·HCl was introduced into the channels of the Cd-MOF and hence the host-guest system (CH3)2NH·HCl@Cd-MOF was formed. The as-synthesized (CH3)2NH·HCl@Cd-MOF displays obvious ferroelectricity at a high frequency of 1 kHz. Such a high-frequency ferroelectric is extremely rare among MOF-based ferroelectric materials, and the high-frequency ferroelectricity means that (CH3)2NH·HCl@Cd-MOF has potential for use in ferroelectric memories. The results again demonstrate that post-synthetic modification is a promising approach for achieving rational and precise design of ferroelectric materials.

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