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1.
Chem Rev ; 123(8): 4353-4415, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-36972332

RESUMO

Vanadium oxides with multioxidation states and various crystalline structures offer unique electrical, optical, optoelectronic and magnetic properties, which could be manipulated for various applications. For the past 30 years, significant efforts have been made to study the fundamental science and explore the potential for vanadium oxide materials in ion batteries, water splitting, smart windows, supercapacitors, sensors, and so on. This review focuses on the most recent progress in synthesis methods and applications of some thermodynamically stable and metastable vanadium oxides, including but not limited to V2O3, V3O5, VO2, V3O7, V2O5, V2O2, V6O13, and V4O9. We begin with a tutorial on the phase diagram of the V-O system. The second part is a detailed review covering the crystal structure, the synthesis protocols, and the applications of each vanadium oxide, especially in batteries, catalysts, smart windows, and supercapacitors. We conclude with a brief perspective on how material and device improvements can address current deficiencies. This comprehensive review could accelerate the development of novel vanadium oxide structures in related applications.

2.
PLoS Genet ; 18(10): e1010211, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36279278

RESUMO

Changes in neurotransmitter receptor abundance at post-synaptic elements play a pivotal role in regulating synaptic strength. For this reason, there is significant interest in identifying and characterizing the scaffolds required for receptor localization at different synapses. Here we analyze the role of two C. elegans post-synaptic scaffolding proteins (LIN-2/CASK and FRM-3/FARP) at cholinergic neuromuscular junctions. Constitutive knockouts or muscle specific inactivation of lin-2 and frm-3 dramatically reduced spontaneous and evoked post-synaptic currents. These synaptic defects resulted from the decreased abundance of two classes of post-synaptic ionotropic acetylcholine receptors (ACR-16/CHRNA7 and levamisole-activated AChRs). LIN-2's AChR scaffolding function is mediated by its SH3 and PDZ domains, which interact with AChRs and FRM-3/FARP, respectively. Thus, our findings show that post-synaptic LIN-2/FRM-3 complexes promote cholinergic synaptic transmission by recruiting AChRs to post-synaptic elements.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Junção Neuromuscular/metabolismo , Receptores Colinérgicos/genética , Receptores Colinérgicos/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Transmissão Sináptica/genética , Colinérgicos/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Helminto/metabolismo
3.
J Cell Sci ; 135(24)2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36453135

RESUMO

Cilia are conserved organelles found in many cell types in eukaryotes, and their dysfunction causes defects in environmental sensing and signaling transduction; such defects are termed ciliopathies. Distinct cilia have cell-specific morphologies and exert distinct functions. However, the underlying mechanisms of cell-specific ciliogenesis and regulation are unclear. Here, we identified a WD40-repeat (WDR) protein, NMTN-1 (the homolog of mammalian WDR47), and show that it is specifically required for ciliogenesis of AWB chemosensory neurons in C. elegans. NMTN-1 is expressed in the AWB chemosensory neuron pair, and is enriched at the basal body (BB) of the AWB cilia. Knockout of nmtn-1 causes abnormal AWB neuron cilia morphology, structural integrity, and induces aberrant AWB-mediated aversive behaviors. We further demonstrate that nmtn-1 deletion affects movement of intraflagellar transport (IFT) particles and their cargo delivery in AWB neurons. Our results indicate that NMTN-1 is essential for AWB neuron ciliary morphology and function, which reveal a novel mechanism for cell-specific ciliogenesis. Given that WDR47/NMTN-1 is conserved in mammals, our findings may help understanding of the process of cell-specific ciliogenesis and provide insights for treating ciliopathies.


Assuntos
Caenorhabditis elegans , Ciliopatias , Animais , Transporte Biológico , Cílios/metabolismo , Neurônios/metabolismo , Ciliopatias/metabolismo , Mamíferos
4.
Langmuir ; 32(3): 759-64, 2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26729057

RESUMO

Vanadium dioxide (VO2) is a well-known thermochromic material with large IR modulating ability, promising for energy-saving smart windows. The main drawbacks of VO2 are its high phase transition temperature (τ(c) = 68°C), low luminous transmission (T(lum)), and weak solar modulating ability (ΔT(sol)). In this paper, the terbium cation (Tb(3+)) doping was first reported to reduce τ(c) and increase T(lum) of VO2 thin films. Compared with pristine VO2, 2 at. % doping level gives both enhanced T(lum) and ΔT(sol) from 45.8% to 54.0% and 7.7% to 8.3%, respectively. The T(lum) increases with continuous Tb(3+) doping and reaches 79.4% at 6 at. % doping level, representing ∼73.4% relative increment compared with pure VO2. This has surpassed the best reported doped VO2 thin films. The enhanced thermochromic properties is meaningful for smart window applications of VO2 materials.

5.
Cell Rep ; 42(6): 112598, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37289584

RESUMO

Age-associated neurodegenerative disorders such as Parkinson's and Alzheimer's diseases are mainly caused by protein aggregation. The etiologies of these neurodegenerative diseases share a chemical environment. However, how chemical cues modulate neurodegeneration remains unclear. Here, we found that in Caenorhabditis elegans, exposure to pheromones in the L1 stage accelerates neurodegeneration in adults. Perception of pheromones ascr#3 and ascr#10 is mediated by chemosensory neurons ASK and ASI. ascr#3 perceived by G protein-coupled receptor (GPCR) DAF-38 in ASK activates glutamatergic transmission into AIA interneurons. ascr#10 perceived by GPCR STR-2 in ASI activates the secretion of neuropeptide NLP-1, which binds to the NPR-11 receptor in AIA. Activation of both ASI and ASK is required and sufficient to remodel neurodevelopment via AIA, which triggers insulin-like signaling and inhibits autophagy in adult neurons non-cell-autonomously. Our work reveals how pheromone perception at the early developmental stage modulates neurodegeneration in adults and provides insights into how the external environment impacts neurodegenerative diseases.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/metabolismo , Transdução de Sinais , Feromônios/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Insulina/metabolismo , Percepção
6.
J Cell Biol ; 222(11)2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37624117

RESUMO

Sexually dimorphic behaviors are ubiquitous throughout the animal kingdom. Although both sex-specific and sex-shared neurons have been functionally implicated in these diverse behaviors, less is known about the roles of sex-shared neurons. Here, we discovered sexually dimorphic cholinergic synaptic transmission in C. elegans occurring at neuromuscular junctions (NMJs), with males exhibiting increased release frequencies, which result in sexually dimorphic locomotion behaviors. Scanning electron microscopy revealed that males have significantly more synaptic vesicles (SVs) at their cholinergic synapses than hermaphrodites. Analysis of previously published transcriptome identified the male-enriched transcripts and focused our attention on UNC-43/CaMKII. We ultimately show that differential accumulation of UNC-43 at cholinergic neurons controls axonal SV abundance and synaptic transmission. Finally, we demonstrate that sex reversal of all neurons in hermaphrodites generates male-like cholinergic transmission and locomotion behaviors. Thus, beyond demonstrating UNC-43/CaMKII as an essential mediator of sex-specific synaptic transmission, our study provides molecular and cellular insights into how sex-shared neurons can generate sexually dimorphic locomotion behaviors.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Junção Neuromuscular , Transmissão Sináptica , Animais , Feminino , Masculino , Caenorhabditis elegans/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Neurônios , Proteínas de Caenorhabditis elegans/genética
7.
Nat Commun ; 14(1): 1436, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36918518

RESUMO

Disturbed inhibitory synaptic transmission has functional impacts on neurodevelopmental and psychiatric disorders. An essential mechanism for modulating inhibitory synaptic transmission is alteration of the postsynaptic abundance of GABAARs, which are stabilized by postsynaptic scaffold proteins and recruited by presynaptic signals. However, how GABAergic neurons trigger signals to transsynaptically recruit GABAARs remains elusive. Here, we show that UNC-43/CaMKII functions at GABAergic neurons to recruit GABAARs and modulate inhibitory synaptic transmission at C. elegans neuromuscular junctions. We demonstrate that UNC-43 promotes presynaptic MADD-4B/Punctin secretion and NRX-1α/Neurexin surface delivery. Together, MADD-4B and NRX-1α recruit postsynaptic NLG-1/Neuroligin and stabilize GABAARs. Further, the excitation of GABAergic neurons potentiates the recruitment of NLG-1-stabilized-GABAARs, which depends on UNC-43, MADD-4B, and NRX-1. These data all support that UNC-43 triggers MADD-4B and NRX-1α, which act as anterograde signals to recruit postsynaptic GABAARs. Thus, our findings elucidate a mechanism for pre- and postsynaptic communication and inhibitory synaptic transmission and plasticity.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Ácido gama-Aminobutírico/metabolismo , Junção Neuromuscular/metabolismo , Sinapses/metabolismo , Transmissão Sináptica/fisiologia
8.
J Mater Sci Mater Med ; 22(7): 1633-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21614594

RESUMO

Dissolution resistance and adhesion strength are two main concerns for long-term stability of surface coated metal implants. In this study, fluorine ions are incorporated into magnesium-containing hydroxyapatite coatings (MgF(y)HA) via sol-gel method to improve the long-term stability of the implants. Surface and interface are studied in terms of phases, depth profiling and chemical bonds by grazing incidence X-ray diffraction, glow discharge optical emission spectroscopy and X-ray photoelectron spectroscopy. The long-term stability is evaluated by dissolution and pull-off test. The results show that fluorine promotes the incorporation of magnesium in HA lattice. The elemental interdiffusion and chemical bonding take place at the coating/substrate interface. Both the dissolution resistance and the adhesion strength are enhanced by fluorine incorporation, thus the long-term stability of the implant is improved.


Assuntos
Materiais Biocompatíveis/química , Durapatita/química , Flúor/química , Magnésio/química , Teste de Materiais , Espectroscopia Fotoeletrônica , Análise Espectral/métodos , Propriedades de Superfície , Difração de Raios X
9.
Cell Cycle ; 20(18): 1799-1811, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34437823

RESUMO

Laryngeal squamous cell cancer (LSCC) is one of the most common malignant tumors in head and neck tumors. Our previous study has revealed that hsa_circ_0006232 is abnormally expressed in LSCC. This study attempts to verify the biological role of hsa_circ_0006232 in LSCC. We found that compared with human bronchial epithelial cells, hsa_circ_0006232 was highly expressed in human LSCC cells (AMC-HN-8 and TU686). Moreover, hsa_circ_0006232 promoted proliferation, migration and invasion of AMC-HN-8 and TU686 cells. Hsa_circ_0006232 promoted the expression of enhancer of zeste homolog 2 (EZH2) and repressed the expression of phosphatase and tensin homolog deleted on chromosome 10 (PTEN). Fused in sarcoma (FUS) interacted with hsa_circ_0006232 and EZH2, and FUS promoted the stabilization of EZH2. Hsa_circ_0006232 inhibited PTEN by promoting FUS expression. Moreover, we constructed a tumor xenograft model by injection of AMC-HN-8 cells with hsa_circ_0006232 knockdown, and we found that hsa_circ_0006232 deficiency decreased tumor growth in mice. Hsa_circ_0006232 silencing repressed EZH2 expression and enhanced PTEN expression in tumor tissues. In conclusion, our data have demonstrated that Hsa_circ_0006232 promotes proliferation, migration and invasion of LSCC cells, and accelerates tumor growth of LSCC through FUS-mediated EZH2 stabilization. Thus, hsa_circ_0006232 may be a novel therapeutic target in LSCC treatment.


Assuntos
Carcinogênese/metabolismo , Progressão da Doença , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Neoplasias Laríngeas/metabolismo , RNA Circular/metabolismo , Proteína FUS de Ligação a RNA/metabolismo , Transdução de Sinais/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Animais , Brônquios/citologia , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Células Epiteliais/metabolismo , Inativação Gênica , Humanos , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , RNA Circular/genética , Proteína FUS de Ligação a RNA/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Transfecção , Carga Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Adv Healthc Mater ; 10(17): e2100221, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34272931

RESUMO

Stretchable electronics have advanced rapidly and many applications require high repeatability and robustness under various mechanical deformations. It has been described here that how a highly stretchable and reliable conductor composite made from helical copper wires and a soft elastomer, named eHelix, can provide mechanically robust and strain-insensitive electronic conductivity for wearable devices. The reversibility of the mechanical behavior of the metal-elastomer system has been studied using finite element modeling methods. Optimal design parameters of such helical metal-elastomer structures are found. The scaling of multiple copper wires into such helical shapes to form a Multi-eHelix system is further shown. With the same elastomer volume, Multi-eHelix has more conductive paths and a higher current density than the single-eHelix. Integrations of these eHelix stretchable conductors with fabrics showed wearable displays that can survive machine-washes and hundreds of mechanical loading cycles. The integration of the eHelix developed by us with a wearable optical heart rate sensor enabled a wearable health monitoring system that can display measured heart rates on clothing. Furthermore, Multi-eHelix conductors are used to connect flexible printed circuit boards and piezoresistive sensors on a tactile sensing glove for the emerging sensorized prosthetics.


Assuntos
Elastômeros , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Frequência Cardíaca , Têxteis
11.
Elife ; 102021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33787493

RESUMO

The development of functional synapses in the nervous system is important for animal physiology and behaviors, and its disturbance has been linked with many neurodevelopmental disorders. The synaptic transmission efficacy can be modulated by the environment to accommodate external changes, which is crucial for animal reproduction and survival. However, the underlying plasticity of synaptic transmission remains poorly understood. Here we show that in Caenorhabditis elegans, the male environment increases the hermaphrodite cholinergic transmission at the neuromuscular junction (NMJ), which alters hermaphrodites' locomotion velocity and mating efficiency. We identify that the male-specific pheromones mediate this synaptic transmission modulation effect in a developmental stage-dependent manner. Dissection of the sensory circuits reveals that the AWB chemosensory neurons sense those male pheromones and further transduce the information to NMJ using cGMP signaling. Exposure of hermaphrodites to the male pheromones specifically increases the accumulation of presynaptic CaV2 calcium channels and clustering of postsynaptic acetylcholine receptors at cholinergic synapses of NMJ, which potentiates cholinergic synaptic transmission. Thus, our study demonstrates a circuit mechanism for synaptic modulation and behavioral flexibility by sexual dimorphic pheromones.


Assuntos
Caenorhabditis elegans/fisiologia , Feromônios/metabolismo , Transmissão Sináptica , Animais , Feminino , Masculino , Junção Neuromuscular/fisiologia , Fatores Sexuais
12.
Yi Chuan ; 31(4): 439-44, 2009 Apr.
Artigo em Zh | MEDLINE | ID: mdl-19586899

RESUMO

Investigation of DNA-protein interactions is fundamental to understand the mechanism underlying a variety of life processes. In this article, various types of biochemical methods in DNA-protein interaction study in vivo and in vitro at the level of DNA, protein, and the complex, respectively were briefly reviewed. Traditional assays including Nitrocellulose filter-binding assay, Footprinting, EMSA, and Southwestern blotting were summarized. In addition, chromatin immunopre-cipitation techniques including nChIP, xChIP, and ChIP-on-chip, which were widely used in epigenetics, were particularly introduced.


Assuntos
Análise de Sequência com Séries de Oligonucleotídeos/métodos , Polimorfismo de Nucleotídeo Único/genética , Genótipo , Modelos Genéticos , Reação em Cadeia da Polimerase
13.
Acta Biomater ; 3(2): 191-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17142117

RESUMO

Fluoridated hydroxyapatite (FHA) coatings were deposited onto Ti6Al4V substrates by sol-gel dip-coating method. X-ray photoelectron spectroscopy results showed that fluoride ions were successfully incorporated into the hydroxyapatite (HA) lattice structure. The dissolution behavior in Tris-buffered physiological saline indicated that all fluoridated HA coatings had lower solubility than that of the pure HA coating. The lowest solubility was obtained at fluoride ion concentrations of 0.8-1.1M. In vitro cell responses were evaluated with human osteosarcoma MG63 cells in terms of cell morphology, proliferation and differentiation (alkaline phosphatase activity and osteocalcin level). For all coatings tested, similar cell morphologies and good cell viability were observed. Coatings fluoridated to 0.8-1.1 had a stronger stimulating effect on cell proliferation and differentiation activities. The influences on cell phenotypes were attributed mainly to a combined ion effect of Ca, P and F released from the coating during dissolution. For the best dissolution resistance and cell activities, it is recommended that the molar level of fluoride ion be from 0.8 to 1.1, such that the coating takes the form of Ca(10)(PO(4))(6)(OH)(1.2-0.9)F(0.8-1.1).


Assuntos
Materiais Revestidos Biocompatíveis/química , Durapatita/química , Flúor/química , Osteoblastos/citologia , Fosfatase Alcalina/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Microanálise por Sonda Eletrônica , Humanos , Íons , Teste de Materiais , Osteossarcoma/metabolismo , Propriedades de Superfície
15.
J Biomed Mater Res A ; 84(3): 769-76, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17635010

RESUMO

Initial cell attachment and spreading of anchorage-dependent cells onto the material surface are crucial concerns for the development of more effective implants. In this study, MG63 cells were employed to investigate the initial cell response to sol-gel derived fluoridated hydroxyapatite (FHA) coatings. Along with that, surface roughness, wettability, and protein adsorption were also characterized for those FHA coatings, respectively. It was observed that both the surface roughness and contact angle have a slight increase in response to the incorporation of more fluorine ions. All FHA coatings showed similar amount of adsorbed proteins (approximately 1.6 microg/cm(2)) upon testing in culture medium. Cell counting showed that no significant difference was observed for the amount of initially attached cells between HA and fluoridated HA coatings during the first 4 h culture. On the other hand, the well-spread cell on all prepared coating surface indicates that the incorporated fluorine ions have no adverse effect on cell spreading process. Therefore, it was suggested from this study that the prepared fluoridated hydroxyapatite coatings have comparable bioactivity to that of pure hydroxyapatite coating, and these results are meaningful for further investigation for application of FHA coatings.


Assuntos
Adesão Celular/fisiologia , Materiais Revestidos Biocompatíveis , Géis , Hidroxiapatitas , Osteoblastos/fisiologia , Linhagem Celular Tumoral , Humanos , Osteoblastos/citologia , Soluções
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