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1.
J Neuroimaging ; 34(2): 167-178, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38183169

RESUMO

Sensory processing disorder (SPD) is a clinical condition characterized by difficulties in the neurological processes of registering, discriminating, organizing, and responding to various sensory sensations. This study aimed to review the association between impaired white matter (WM) tract structure and neurofunctional deficits in children with SPD using diffusion tensor imaging (DTI). A comprehensive literature search was conducted using the online databases Google Scholar and PubMed (from 2010 to July 2023), resulting in the selection of nine relevant studies. Findings revealed that the splenium of the corpus callosum (SCC), superior longitudinal fasciculus (SLF), posterior corona radiata (PCR), and posterior thalamic radiation (PTR) exhibited reduced microstructural integrity, strongly associated with SPD. Specifically, auditory over-responsivity, a subtype of SPD, was linked to impaired integrity of the PCR, PTR, anterior corona radiata, and SLF. Tactile over-responsivity (TOR) was correlated with markers of decreased integrity in the SCC, superior corona radiata, and left PTR. Among the DTI parameters, decreased fractional anisotropy (FA) emerged as the most reliable factor for identifying SPD, followed by increased radial diffusivity (RD) and mean diffusivity (MD). Notably, significant correlations were observed between with auditory over-responsivity and TOR with the DTI parameters (positive for FA and negative for RD and MD). Overall, this review confirms the impaired integrity of specific WM tracts in children with SPD and establishes correlations between DTI parameters and neurobehavioral deficits associated with the disorder. The insights gained from this review contribute to a better understanding of SPD and hold clinical implications for its diagnosis and treatment.


Assuntos
Imagem de Tensor de Difusão , Substância Branca , Criança , Humanos , Imagem de Tensor de Difusão/métodos , Encéfalo/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Percepção
2.
Reprod Biol ; 20(4): 589-594, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32972883

RESUMO

The a disintegrin and metalloprotease (ADAM) family proteins comprise a group of membrane-anchored proteins. ADAM32 is expressed specifically in testis and is closely related phylogenetically to ADAM2 and ADAM3, which are known to be critical for fertilization in mice. To assess the biological role of ADAM32, we analyzed Adam32-mutant mice. We found that male mice lacking ADAM32 have normal fertility, testicular integrity, and sperm characteristics. ADAM32 was found to exist at lower levels than ADAM2 and ADAM3 in wild-type testis and sperm, respectively. The present study demonstrates that ADAM32 is dispensable for fertility and appears to be functionally unrelated to ADAM2 and ADAM3 in mice.


Assuntos
Proteínas ADAM/deficiência , Proteínas ADAM/fisiologia , Fertilidade/fisiologia , Expressão Gênica/fisiologia , Testículo/metabolismo , Proteínas ADAM/análise , Proteínas ADAM/genética , Animais , Cruzamento , Epididimo/anatomia & histologia , Feminino , Fertilinas/análise , Masculino , Glicoproteínas de Membrana/análise , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/química , Espermatozoides/fisiologia , Testículo/anatomia & histologia , Testículo/química
3.
BMC Genomics ; 19(1): 539, 2018 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-30012089

RESUMO

BACKGROUND: Spermatogenesis, which is the complex and highly regulated process of producing haploid spermatozoa, involves testis-specific transcripts. Recent studies have discovered that long noncoding RNAs (lncRNAs) are novel regulatory molecules that play important roles in various biological processes. However, there has been no report on the comprehensive identification of testis-specific lncRNAs in mice. RESULTS: We performed microarray analysis of transcripts from mouse brain, heart, kidney, liver and testis. We found that testis harbored the highest proportion of tissue-specific lncRNAs (11%; 1607 of 14,256). Testis also harbored the largest number of tissue-specific mRNAs among the examined tissues, but the proportion was lower than that of lncRNAs (7%; 1090 of 16,587). We categorized the testis-specific lncRNAs and found that a large portion corresponded to long intergenic ncRNAs (lincRNAs). Genomic analysis identified 250 protein-coding genes located near (≤ 10 kb) 194 of the loci encoding testis-specific lincRNAs. Gene ontology (GO) analysis showed that these protein-coding genes were enriched for transcriptional regulation-related terms. Analysis of male germ cell-related cell lines (F9, GC-1 and GC-2) revealed that some of the testis-specific lncRNAs were expressed in each of these cell lines. Finally, we arbitrarily selected 26 testis-specific lncRNAs and performed in vitro expression analysis. Our results revealed that all of them were expressed exclusively in the testis, and 23 of the 26 showed germ cell-specific expression. CONCLUSION: This study provides a catalog of testis-specific lncRNAs and a basis for future investigation of the lncRNAs involved in spermatogenesis and testicular functions.


Assuntos
RNA Longo não Codificante/genética , Testículo/metabolismo , Animais , Linhagem Celular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , Masculino , Camundongos , Fases de Leitura Aberta , RNA Longo não Codificante/classificação , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espermatogênese/genética , Testículo/citologia
4.
ACS Appl Mater Interfaces ; 10(24): 20929-20937, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29883084

RESUMO

Single-crystalline gold nanowires (Au NWs) are directly synthesized by the photocatalytic reduction of an aqueous HAuCl4 solution inside high-aspect-ratio TiO2 nanotubes (NTs). Crystalline TiO2 (anatase) NTs are prepared by the template-assisted atomic layer deposition technique with a subsequent annealing. Under the irradiation of ultraviolet light, photoexcited electrons are formed on the surfaces of TiO2 NTs and could reduce Au ions to create nuclei without using any surfactant, reducing agent, and/or seed. Once nucleation occurred, high-aspect-ratio Au NWs are grown inside the TiO2 NTs in a diffusion-controlled manner. As the solution pH increased, the nucleation/growth rate decreased and twin-free (or not observed), single-crystalline Au NWs are formed. At a pH above 6, the nucleation/growth rates increased and Au nanoparticles are observed both inside and outside of the TiO2 NTs. The confined nanoscale geometries of the interior of the TiO2 NTs are found to play a key role in the controlled diffusion of Au species and in determining the crystal morphology of the resulting Au NWs.

5.
Adv Mater ; 30(16): e1706261, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29513390

RESUMO

Gold is known as the most noblest metal with only face-centered cubic (fcc) structure in ambient conditions. Here, stable hexagonal non-close-packed (ncp) gold nanowires (NWs), having a diameter of about 50 nm and aspect ratios of well over 400, are reported. Au NWs are grown in the confined system of nanotubular TiO2 arrays via photoelectrochemical reduction of HAuCl4 precursors. Some of the resulting Au NWs are proved to have sixfold rotational symmetry, observed by transmission electron microscopy tilting experiments. This new polymorph is identified as a hexagonal ncp-structure with lattice parameters of a = 2.884 Å and c = 7.150 Å, showing quite a large interplanar spacing (c/a ≈ 2.48). That is, Au atoms are close-packed along the ab plane, but each plane is not closely stacked along the c axis like in graphite. The structure is usually expected to be unstable, but the present ncp-2H gold is stable under ambient conditions and intense electron beam irradiation, and shows thermal stability up to 400 °C. Moreover, the resulting physical properties as a result of the corresponding change in electronic structures are investigated by comparing the optical properties of fcc and ncp-2H Au NWs.

6.
ACS Nano ; 12(2): 2008-2016, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29390178

RESUMO

Direct graphene synthesis on substrates via chemical vapor deposition (CVD) is an attractive approach for manufacturing flexible electronic devices. The temperature for graphene synthesis must be below ∼200 °C to prevent substrate deformation while fabricating flexible devices on plastic substrates. Herein, we report a process whereby defect-free graphene is directly synthesized on a variety of substrates via the introduction of an ultrathin Ti catalytic layer, due to the strong affinity of Ti to carbon. Ti with a thickness of 10 nm was naturally oxidized by exposure to air before and after the graphene synthesis, and the various functions of neither the substrates nor the graphene were influenced. This report offers experimental evidence of high-quality graphene synthesis on Ti-coated substrates at 150 °C via CVD. The proposed methodology was applied to the fabrication of flexible and transparent thin-film capacitors with top electrodes of high-quality graphene.

7.
J Am Chem Soc ; 140(4): 1358-1364, 2018 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-29300468

RESUMO

Organic-inorganic halide perovskite is believed to be a potential candidate for high efficiency solar cells because power conversion efficiency (PCE) was certified to be more than 22%. Nevertheless, mismatch of PCE due to current density (J)-voltage (V) hysteresis in perovskite solar cells is an obstacle to overcome. There has been much lively debate on the origin of J-V hysteresis; however, effective methodology to solve the hysteric problem has not been developed. Here we report a universal approach for hysteresis-free perovskite solar cells via defect engineering. A severe hysteresis observed from the normal mesoscopic structure employing TiO2 and spiro-MeOTAD is almost removed or does not exist upon doping the pure perovskites, CH3NH3PbI3 and HC(NH2)2PbI3, and the mixed cation/anion perovskites, FA0.85MA0.15PbI2.55Br0.45 and FA0.85MA0.1Cs0.05PbI2.7Br0.3, with potassium iodide. Substantial reductions in low-frequency capacitance and bulk trap density are measured from the KI-doped perovskite, which is indicative of trap-hysteresis correlation. A series of experiments with alkali metal iodides of LiI, NaI, KI, RbI and CsI reveals that potassium ion is the right element for hysteresis-free perovskite. Theoretical studies suggest that the atomistic origin of the hysteresis of perovskite solar cells is not the migration of iodide vacancy but results from the formation of iodide Frenkel defect. Potassium ion is able to prevent the formation of Frenkel defect since K+ energetically prefers the interstitial site. A complete removal of hysteresis is more pronounced at mixed perovskite system as compared to pure perovskites, which is explained by lower formation energy of K interstitial (-0.65 V for CH3NH3PbI3 vs -1.17 V for mixed perovskite). The developed KI doping methodology is universally adapted for hysteresis-free perovskite regardless of perovskite composition and device structure.

8.
Sci Adv ; 3(3): e1602215, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28435863

RESUMO

We describe the spontaneous formation of composite chalcogenide materials that consist of two-dimensional (2D) materials dispersed in bulk and their unusual charge transport properties for application in hydrogen evolution reactions (HERs). When MoS2 as a representative 2D material is deposited on transition metals (such as Cu) in a controlled manner, the sulfidation reactions also occur with the metal. This process results in remarkably unique structures, that is, bulk layered heterojunctions (BLHJs) of Cu-Mo-S that contain MoS2 flakes inside, which are uniformly dispersed in the Cu2S matrix. The resulting structures were expected to induce asymmetric charge transfer via layered frameworks and tested as electrocatalysts for HERs. Upon suitable thermal treatments, the BLHJ surfaces exhibited the efficient HER performance of approximately 10 mA/cm2 at a potential of -0.1 V versus a reversible hydrogen electrode. The Tafel slope was approximately 30 to 40 mV per decade. The present strategy was further generalized by demonstrating the formation of BLHJs on other transition metals, such as Ni. The resulting BLHJs of Ni-Mo-S also showed the remarkable HER performance and the stable operation over 10 days without using Pt counter electrodes by eliminating any possible issues on the Pt contamination.

9.
Opt Express ; 24(14): 15171-9, 2016 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-27410795

RESUMO

Metal/TiO2 hybrid nanostructures offer more efficient charge separation and a broader range of working wavelengths for photocatalytic reactions. The sizes and shapes of such hybrid nanostructures can affect the charge separation performance when the structures interact with light, but assessments of the interaction of light with these metal-TiO2 nanostructures have only been carried out on ensemble averages, hindering both systematic descriptions of such hybrid structures and the design of new ones. Here, we fabricated TiO2 nanotubes (NTs) with and without core Au nanowires (NWs), and used spectroscopy and calculations to assess their scattering and absorption of light at the single NW level. According to the results of spectral imaging and numerical calculations, the Au/TiO2 NWs scattered and absorbed light substantially more strongly than did the plain TiO2 NTs. Measurements of the degradation of the AO7 dye to assess the photocatalytic performance of the Au/TiO2 NWs were consistent with optical measurements demonstrating a two-fold improvement over plain TiO2 NTs under 360-nm-wavelength UV illumination. Our results suggests that nanoscale optical imaging can be used to visualize the performance of the photocatalytic reaction at the single nano-object level.

10.
Nanoscale ; 8(22): 11403-12, 2016 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-27216291

RESUMO

NiO is a wide band gap p-type oxide semiconductor and has potential for applications in solar energy conversion as a hole-transporting layer (HTL). It also has good optical transparency and high chemical stability, and the capability of aligning the band edges to the perovskite (CH3NH3PbI3) layers. Ultra-thin and un-doped NiO films with much less absorption loss were prepared by atomic layer deposition (ALD) with highly precise control over thickness without any pinholes. Thin enough (5-7.5 nm in thickness) NiO films with the thickness of few time the Debye length (LD = 1-2 nm for NiO) show enough conductivities achieved by overlapping space charge regions. The inverted planar perovskite solar cells with NiO films as HTLs exhibited the highest energy conversion efficiency of 16.40% with high open circuit voltage (1.04 V) and fill factor (0.72) with negligible current-voltage hysteresis.

11.
PLoS One ; 10(5): e0128014, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26020533

RESUMO

The eukaryotic translation elongation factor 1 (eEF1) has two components: the G-protein eEF1A and the nucleotide exchange factor eEF1B. In plants, eEF1B is itself composed of a structural protein (eEF1Bγ) and two nucleotide exchange subunits (eEF1Bα and eEF1Bß). To test the effects of elongation factors on virus infection, we isolated eEF1A and eEF1B genes from pepper (Capsicum annuum) and suppressed their homologs in Nicotiana benthamiana using virus-induced gene silencing (VIGS). The accumulation of a green fluorescent protein (GFP)-tagged Potato virus X (PVX) was significantly reduced in the eEF1Bß- or eEF1BÉ£-silenced plants as well as in eEF1A-silenced plants. Yeast two-hybrid and co-immunoprecipitation analyses revealed that eEF1Bα and eEF1Bß interacted with eEF1A and that eEF1A and eEF1Bß interacted with triple gene block protein 1 (TGBp1) of PVX. These results suggest that both eEF1A and eEF1Bß play essential roles in the multiplication of PVX by physically interacting with TGBp1. Furthermore, using eEF1Bß deletion constructs, we found that both N- (1-64 amino acids) and C-terminal (150-195 amino acids) domains of eEF1Bß are important for the interaction with PVX TGBp1 and that the C-terminal domain of eEF1Bß is involved in the interaction with eEF1A. These results suggest that eEF1Bß could be a potential target for engineering virus-resistant plants.


Assuntos
Capsicum/metabolismo , Nicotiana/metabolismo , Fator 1 de Elongação de Peptídeos/metabolismo , Doenças das Plantas/virologia , Potexvirus/metabolismo , RNA Helicases/metabolismo , Proteínas Virais/metabolismo , Capsicum/genética , Capsicum/virologia , Resistência à Doença , Fator 1 de Elongação de Peptídeos/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Potexvirus/genética , RNA Helicases/genética , Nicotiana/genética , Nicotiana/virologia , Proteínas Virais/genética
12.
ChemSusChem ; 8(14): 2363-71, 2015 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-25802052

RESUMO

Titanium dioxide (TiO2 ), tin dioxide (SnO2 ), and heterostructured TiO2 /SnO2 nanotube (NT) arrays have been fabricated by template-assisted atomic-layer deposition (ALD) for use as anodes in a lithium-ion battery (LIB). TiO2 NT arrays with 8 nm thick walls showed higher capacity (≈250 mA h g(-1) after the 50th cycle at a rate of C/10) than the typical theoretical capacity of bulk TiO2 and a radically improved capacity retention property upon cycling. SnO2 NT arrays with different wall thicknesses (8, 10, 13, and 20 nm) were also fabricated and their electrochemical performances were measured. All of the SnO2 NT arrays showed substantially higher initial irreversible capacity and higher reversible capacity than those of bulk TiO2 . Thinner walls of the SnO2 NTs result in better capacity retention. Heterotubular structures of TiO2 (5 nm)/SnO2 (10 nm)/TiO2 (5 nm) were successfully fabricated, and displayed a sufficiently high capacity (≈300 mA h g(-1) after 50 cycles) with exceptionally improved cycling performance up to the 50th cycle.


Assuntos
Fontes de Energia Elétrica , Lítio/química , Nanotubos/química , Compostos de Estanho/química , Titânio/química , Eletrodos , Modelos Moleculares , Conformação Molecular , Propriedades de Superfície
13.
Nano Lett ; 14(8): 4413-7, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-25002075

RESUMO

Both enhancing the excitons' lifetime and ingeniously controlling the spatial charge transfer are the key to the realization of efficiently photocatalytic and artificially photosynthetic devices. Nanostructured metal/metal-oxide interfaces often exhibit improved energy conversion efficiency. Understanding the surface potential changes of nano-objects under light illumination is crucial in photoelectrochemical cells. Under ultraviolet (UV) illumination, here, we directly observed the charge separation phenomena at the Au-nanoparticle/TiO2-nanotube interfaces by using Kelvin probe force microscopy. The surface potential maps of TiO2 nanotubes with and without Au nanoparticles were compared on the effect of different substrates. We observed that in a steady state, approximately 0.3 electron per Au particle of about 4 nm in diameter is effectively charged and consequently screens the surface potential of the underlying TiO2 nanotubes. Our observations should help design improved photoelectrochemical devices for energy conversion applications.

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