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1.
Nanoscale ; 13(45): 19264-19273, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34787629

RESUMO

Interlayer vibrations with discrete quantized modes in two-dimensional (2D) materials can be excited by ultrafast light due to the inherent low dimensionality and van der Waals force as a restoring force. Controlling such interlayer vibrations in layered materials, which are closely related to fundamental nanomechanical interactions and thermal transport, in spatial- and time-domain provides an in-depth understanding of condensed matters and potential applications for advanced phononic and photonics devices. The manipulation of interlayer vibrational modes has been implemented in a spatial domain through material design to develop novel optoelectronic and phononic devices with various 2D materials, but such control in a time domain is still lacking. We present an all-optical method for controlling the interlayer vibrations in a highly precise manner with Bi2Se3 as a promising optoelectronic and thermoelasticity material in layered structures using a coherently controlled pump and probe scheme. The observed thickness-dependent fast interlayer breathing modes and substrate-induced slow interfacial modes can be exactly explained by a modified linear chain model including coupling effect with substrate. In addition, the results of coherent control experiments also agree with the simulation results based on the interference of interlayer vibrations. This investigation is universally applicable for diverse 2D materials and provides insight into the interlayer vibration-related dynamics and novel device implementation based on an ultrafast timescale interlayer-spacing modulation scheme.

2.
Cancer Res Treat ; 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34793663

RESUMO

Purpose: This study aimed to investigate the methylation status of major histone modification sites in primary central nervous system lymphoma (PCNSL) samples and examine their prognostic roles in patients with PCNSL. Materials and Method: Between 2007 and 2020, 87 patients were histopathologically diagnosed with PCNSL. We performed immunohistochemical staining of the formalin-fixed paraffin-embedded samples of PCNSL for major histone modification sites, such as H3K4, H3K9, H3K27, H3K14, and H3K36. After detection of meaningful methylation sites, we examined histone modification enzymes that induce methylation or demethylation at each site using immunohistochemical staining. The meaningful immunoreactivity was validated by western blotting using fresh tissue of PCNSL. Results: More frequent recurrences were found in hypomethylation of H3K4me3 (p=0.004) and hypermethylation of H3K27me2 (p<0.001) and H3K27me3 (p=0.002). These factors were also statistically related to short PFS and OS in the univariate and multivariate analyses. Next, histone modification enzymes inducing the demethylation of H3K4 (lysine-specific demethylase (LSD)-1/2 and Jumonji AT-rich interactive domain 1A (JARID1A-D)) and methylation of H3K27 (enhancer of zeste homolog (EZH)-1/2) were immunohistochemically stained. Among them, the immunoreactivity of JARID1A inversely associated with the methylation status of H3K4me3 (R2=-1.431), and immunoreactivity of EZH2 was directly associated with the methylation status of H3K27me2 (R2=0.667) and H3K27me3 (R2=0.604). These results were validated by western blotting in fresh PCNSL samples. Conclusion: Our study suggests that hypomethylation of H3K4me3 and hypermethylation of H3K27me2 and H3K27me3 could be associated with poor outcomes in patients with PCNSL and that these relationships are modified by JARID1A and EZH2.

3.
Polymers (Basel) ; 13(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34301075

RESUMO

Rubber compounding with two or more components has been extensively employed to improve various properties. In particular, natural rubber (NR)/ethylene-propylene-diene monomer rubber (EPDM) blends have found use in tire and automotive parts. Diverse fillers have been applied to NR/EPDM blends to enhance their mechanical properties. In this study, a new class of mineral filler, phlogopite, was incorporated into an NR/EPDM blend to examine the mechanical, curing, elastic, and morphological properties of the resulting material. The combination of aminoethylaminopropyltrimethoxysilane (AEAPS) and stearic acid (SA) compatibilized the NR/EPDM/phlogopite composite, further improving various properties. The enhanced properties were compared with those of NR/EPDM/fillers composed of silica or carbon black (CB). Compared with the NR/EPDM/silica composite, the incompatibilized NR/EPDM/phlogopite composite without AEAPS exhibited poorer properties, but NR/EPDM/phlogopite compatibilized by AEAPS and SA showed improved properties. Most properties of the compatibilized NR/EPDM/phlogopite composite were similar to those of the NR/EPDM/CB composite, except for the lower abrasion resistance. The NR/EPDM/phlogopite/AEAPS rubber composite may potentially be used in various applications by replacing expensive fillers, such as CB.

4.
Front Vet Sci ; 8: 652224, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33898546

RESUMO

This study aimed to identify the expression profile of circulating microRNAs in dogs with eccentric or concentric cardiac hypertrophy. A total of 291 microRNAs in serum samples of five dogs with myxomatous mitral valve degeneration (MMVD) and five dogs with pulmonic stenosis (PS) were compared with those of five healthy dogs using microarray analysis. Results of microarray analysis revealed up-regulation of cfa-miR-130b [fold change (FC) = 2.13, p = 0.014), down-regulation of cfa-miR-375 (FC = 1.51, p = 0.014), cfa-miR-425 (FC = 2.56, p = 0.045), cfa-miR-30d (FC = 3.02, p = 0.047), cfa-miR-151 (FC = 1.89, p = 0.023), cfa-miR-19b (FC = 3.01, p = 0.008), and cfa-let-7g (FC = 2.53, p = 0.015) in MMVD group which showed eccentric cardiac hypertrophy, up-regulation of cfa-miR-346 (FC = 2.74, p = 0.032), down-regulation of cfa-miR-505 (FC = 1.56, p = 0.016) in PS group which showed concentric cardiac hypertrophy, and down-regulation of cfa-miR-30c (FC = 3.45, p = 0.013 in MMVD group; FC = 3.31, p = 0.014 in PS group) and cfa-let-7b (FC = 11.42, p = 0.049 in MMVD group; FC = 5.88, p = 0.01 in PS group) in both MMVD and PS groups. In addition, the unsupervised hierarchical clustering of differentially expressed microRNAs in each group resulted in complete separation of healthy dogs from dogs with heart diseases. Therefore, eleven microRNAs among 291 microRNAs were identified as differentially expressed circulating microRNAs related to MMVD or PS in dogs. This pilot study demonstrates that the microRNAs identified in this study could be possible candidates for novel biomarker or therapeutic target related to cardiac hypertrophy in dogs.

5.
Nanoscale Res Lett ; 16(1): 7, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33409649

RESUMO

Topologically protected chiral skyrmions are an intriguing spin texture that has attracted much attention because of fundamental research and future spintronic applications. MnSi with a non-centrosymmetric structure is a well-known material hosting a skyrmion phase. To date, the preparation of MnSi crystals has been investigated by using special instruments with an ultrahigh vacuum chamber. Here, we introduce a facile way to grow MnSi films on a sapphire substrate using a relatively low vacuum environment of conventional magnetron sputtering. Although the as-grown MnSi films have a polycrystalline nature, a stable skyrmion phase in a broad range of temperatures and magnetic fields is observed via magnetotransport properties including phenomenological scaling analysis of the Hall resistivity contribution. Our findings provide not only a general way to prepare the materials possessing skyrmion phases but also insight into further research to stimulate more degrees of freedom in our inquisitiveness.

6.
Nanoscale Horiz ; 6(2): 139-147, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33367448

RESUMO

Recently, various efforts have been made to implement synaptic characteristics with a ferroelectric field-effect transistor (FeFET), but in-depth physical analyses have not been reported thus far. Here, we investigated the effects by (i) the formation temperature of the ferroelectric material, poly(vinylidene fluoride-trifluoroethylene) P(VDF-TrFE) and (ii) the nature of the contact metals (Ti, Cr, Pd) of the FeFET on the operating performance of a FeFET-based artificial synapse in terms of various synaptic performance indices. Excellent ferroelectric properties were induced by maximizing the size and coverage ratio of the ß-phase domains by annealing the P(VDF-TrFE) film at 140 °C. A metal that forms a relatively high barrier improved the dynamic range and nonlinearity by suppressing the contribution of the tunneling current to the post-synaptic current. Subsequently, we studied the influence of the synaptic characteristics on the training and recognition tasks by using two MNIST datasets (fashion and handwritten digits) and the multi-layer perceptron concept of neural networks.

7.
Cancers (Basel) ; 12(12)2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33291558

RESUMO

PURPOSE: The objective of this study was to investigate the epigenetic role of histone lysine methylation/demethylation on the expression of epithelial-to-mesenchymal transition (EMT) associated transcriptional factors (TFs) during the metastasis of lung adenocarcinoma to the brain. METHODS: Paired samples of lung adenocarcinoma and brain metastasis (BM) were analyzed in 46 individual patients. Both samples were obtained by surgical resection or biopsy of the lung and brain. The paraffin-fixed formalin-embedded samples were obtained from the pathology archives in our institute. In samples of lung adenocarcinoma and BM, immunohistochemical staining was performed for epithelial markers, mesenchymal markers, EMT-TFs, histone lysine methyltransferase and demethylase. RESULTS: The immunoreactivity of EMT-TFs such as Slug (15.6% vs. 42.6%, p = 0.005), Twist (23.6% vs. 45.9%, p = 0.010) and ZEB1 (15.0% vs. 55.9%, p = 0.002) was increased in BM compared with that in lung adenocarcinoma. Epigenetic inducers such as H3K4 methyltransferase (MLL4, p = 0.018) and H3K36me3 demethylase (UTX, p = 0.003) were statistically increased, and epigenetic repressors such as EZH2 (H3K27 methyltransferase, p = 0.046) were significantly decreased in BM compared with those in lung adenocarcinoma. The expression of UTX-ZEB1 (R2 linear = 1.204) and MLL4-Slug (R2 linear = 0.987) was increased in direct proportion, and EZH2-Twist (R2 linear = -2.723) decreased in reverse proportion. CONCLUSIONS: The results suggest that certain histone lysine methyltransferase/demethylase, such as MLL4, UTX, and EZH2, regulate the expression of EMT-TFs such as Slug, ZEB1, and Twist epigenetically, which may thereby influence cancer metastasis from the lung to the brain.

8.
BMC Cancer ; 20(1): 694, 2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32718341

RESUMO

BACKGROUND: Early diagnosis and continuous monitoring are necessary for an efficient management of cervical cancers (CC). Liquid biopsy, such as detecting circulating tumor DNA (ctDNA) from blood, is a simple, non-invasive method for testing and monitoring cancer markers. However, tumor-specific alterations in ctDNA have not been extensively investigated or compared to other circulating biomarkers in the diagnosis and monitoring of the CC. Therfore, Next-generation sequencing (NGS) analysis with blood samples can be a new approach for highly accurate diagnosis and monitoring of the CC. METHOD: Using a bioinformatics approach, we designed a panel of 24 genes associated with CC to detect and characterize patterns of somatic single-nucleotide variations, indels, and copy number variations. Our NGS CC panel covers most of the genes in The Cancer Genome Atlas (TCGA) as well as additional cancer driver and tumor suppressor genes. We profiled the variants in ctDNA from 24 CC patients who were being treated with systemic chemotherapy and local radiotherapy at the Jeonbuk National University Hospital, Korea. RESULT: Eighteen out of 24 genes in our NGS CC panel had mutations across the 24 CC patients, including somatic alterations of mutated genes (ZFHX3-83%, KMT2C-79%, KMT2D-79%, NSD1-67%, ATM-38% and RNF213-27%). We demonstrated that the RNF213 mutation could be used potentially used as a monitoring marker for response to chemo- and radiotherapy. CONCLUSION: We developed our NGS CC panel and demostrated that our NGS panel can be useful for the diagnosis and monitoring of the CC, since the panel detected the common somatic variations in CC patients and we observed how these genetic variations change according to the treatment pattern of the patient.


Assuntos
DNA Tumoral Circulante/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Mutação , Neoplasias do Colo do Útero/genética , Adenocarcinoma/sangue , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Adenosina Trifosfatases/genética , Idoso , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , DNA Tumoral Circulante/sangue , Classe I de Fosfatidilinositol 3-Quinases/genética , Proteínas de Ligação a DNA/genética , Feminino , Marcadores Genéticos , Proteínas de Homeodomínio/genética , Humanos , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Estudos Prospectivos , Proteínas Proto-Oncogênicas p21(ras)/genética , Sensibilidade e Especificidade , Ubiquitina-Proteína Ligases/genética , Neoplasias do Colo do Útero/sangue , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/terapia
9.
Sci Adv ; 6(13): eaay6994, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32284967

RESUMO

The clinical use of human bone marrow-derived mesenchymal stem cells (BM-MSCs) has been hampered by their poor performance after transplantation into failing hearts. Here, to improve the therapeutic potential of BM-MSCs, we developed a strategy termed in vivo priming in which BM-MSCs are primed in vivo in myocardial infarction (MI)-induced hearts through genetically engineered hepatocyte growth factor-expressing MSCs (HGF-eMSCs) that are encapsulated within an epicardially implanted 3D cardiac patch. Primed BM-MSCs through HGF-eMSCs exhibited improved vasculogenic potential and cell viability, which ultimately enhanced vascular regeneration and restored cardiac function to the MI hearts. Histological analyses further demonstrated that the primed BM-MSCs survived longer within a cardiac patch and conferred cardioprotection evidenced by substantially higher numbers of viable cardiomyocytes in the MI hearts. These results provide compelling evidence that this in vivo priming strategy can be an effective means to enhance the cardiac repair of MI hearts.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Cardiopatias/terapia , Fator de Crescimento de Hepatócito/genética , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Animais , Técnicas de Cultura de Células , Terapia Baseada em Transplante de Células e Tecidos/métodos , Modelos Animais de Doenças , Expressão Gênica , Engenharia Genética , Cardiopatias/etiologia , Fator de Crescimento de Hepatócito/metabolismo , Fator de Crescimento de Hepatócito/farmacologia , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/efeitos dos fármacos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/terapia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Suínos
10.
Stat Biopharm Res ; 12(3): 303-310, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33880140

RESUMO

As a national public health surveillance resource, Vaccine Adverse Event Reporting System (VAERS) is a key component in ensuring the safety of vaccines. Numerous methods have been used to conduct safety studies with the VAERS database. These efforts focus on the downstream statistical analysis of the vaccine and adverse event associations. In this paper, we primarily focus on processing the raw data in VAERS before the analysis step, which is also an important part of the signal detection process. Due to the semi-annual update in the Medical Dictionary for Regulatory Activities (MedDRA) coding system, adverse event terms that describe the same symptom might change in VAERS; therefore, we identify these terms and combine them to increase the signal detection power. We also consider the uncertainty of the vaccine and adverse event pairs that arise from reports with multiple vaccines. Finally, we discuss four commonly used statistics in assessing the vaccine and adverse event associations, and propose to use the statistics that are robust to the reporting bias in VAERS and adjust for potential confounders of the vaccine and adverse event association to increase signal detection accuracy.

11.
J Tissue Eng ; 11: 2041731420953413, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-35003614

RESUMO

Since myocardial infarction (MI) excessively damage the myocardium and blood vessels, the therapeutic approach for treating MI hearts should simultaneously target these two major components in the heart to achieve comprehensive cardiac repair. Here, we investigated a combinatory platform of ETV2 and Gata4, Mef2c and Tbx5 (GMT) transcription factors to develop a strategy that can rejuvenate both myocardium and vasculatures together in MI hearts. Previously ETV2 demonstrated significant effects on neovascularization and GMT was known to directly reprogram cardiac fibroblasts into cardiomyocytes under in vivo condition. Subsequently, intramyocardial delivery of a combination of retroviral GMT and adenoviral ETV2 particles into the rat MI hearts significantly increased viable myocardium area, capillary density compared to ETV2 or GMT only treated hearts, leading to improved heart function and reduced scar formation. These results demonstrate that this combinatorial gene therapy can be a promising approach to enhance the cardiac repair in MI hearts.

12.
ACS Omega ; 4(15): 16578-16584, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31616838

RESUMO

The key of spintronic devices using the spin-transfer torque phenomenon is the effective reduction of switching current density by lowering the damping constant and the saturation magnetization while retaining strong perpendicular magnetic anisotropy. To reduce the saturation magnetization, particular conditions such as specific substitutions or buffer layers are required. Herein, we demonstrate highly reduced saturation magnetization in tetragonal D022 Mn3-x Ga thin films prepared by rf magnetron sputtering, where the epitaxial growth is examined on various substrates without any buffer layer. As the lattice mismatch between the sample and the substrate decreases from LaAlO3 and (LaAlO3)0.3(Sr2AlTaO6)0.7 to SrTiO3, the quality of Mn3-x Ga films is improved together with the magnetic and electronic properties. Especially, the Mn3-x Ga thin film epitaxially grown on the SrTiO3 substrate, fully oriented along the c axis perpendicular to the film plane, exhibits significantly reduced saturation magnetization as low as 0.06 µB, compared to previous results. By the structural and chemical analyses, we find that the predominant removal of Mn II atoms and the large population of Mn3+ ions affect the reduced saturation magnetization. Our findings provide insights into the magnetic properties of Mn3-x Ga crystals, which promise great potential for spin-related device applications.

13.
Exp Mol Med ; 51(9): 1, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31484921

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

14.
Nat Commun ; 10(1): 3123, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311935

RESUMO

Since both myocardium and vasculature in the heart are excessively damaged following myocardial infarction (MI), therapeutic strategies for treating MI hearts should concurrently target both so as to achieve true cardiac repair. Here we demonstrate a concomitant method that exploits the advantages of cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs) and human mesenchymal stem cell-loaded patch (hMSC-PA) to amplify cardiac repair in a rat MI model. Epicardially implanted hMSC-PA provide a complimentary microenvironment which enhances vascular regeneration through prolonged secretion of paracrine factors, but more importantly it significantly improves the retention and engraftment of intramyocardially injected hiPSC-CMs which ultimately restore the cardiac function. Notably, the majority of injected hiPSC-CMs display adult CMs like morphology suggesting that the secretomic milieu of hMSC-PA constitutes pleiotropic effects in vivo. We provide compelling evidence that this dual approach can be a promising means to enhance cardiac repair on MI hearts.


Assuntos
Coração/fisiologia , Transplante de Células-Tronco Mesenquimais/métodos , Infarto do Miocárdio/terapia , Miócitos Cardíacos/transplante , Regeneração , Animais , Diferenciação Celular , Células Cultivadas , Modelos Animais de Doenças , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , Injeções Intralesionais , Masculino , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/patologia , Miocárdio/citologia , Miocárdio/patologia , Miócitos Cardíacos/fisiologia , Ratos , Ratos Endogâmicos F344 , Resultado do Tratamento
15.
Exp Mol Med ; 51(2): 1-14, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755583

RESUMO

Vascular regeneration in ischemic hearts has been considered a target for new therapeutic strategies. It has been reported that ETV2 is essential for vascular development, injury-induced neovascularization and direct cell reprogramming of non-endothelial cells into endothelial cells. Thus, the objective of this study was to explore the therapeutic potential of ETV2 in murine models of myocardial infarction in vivo. Direct myocardial delivery of lentiviral ETV2 into rodents undergoing myocardial infarction dramatically upregulated the expression of markers for angiogenesis as well as anti-fibrosis and anti-inflammatory factors in vivo. Consistent with these findings, echocardiography showed significantly improved cardiac function in hearts with induced myocardial infarction upon ETV2 injection compared to that in the control virus-injected group as determined by enhanced ejection fraction and fractional shortening. In addition, ETV2-injected hearts were protected against massive fibrosis with a remarkable increase in capillary density. Interestingly, major fractions of capillaries were stained positive for ETV2. In addition, ECs infected with ETV2 showed enhanced proliferation, suggesting a direct role of ETV2 in vascular regeneration in diseased hearts. Furthermore, culture media from ETV2-overexpressing cardiac fibroblasts promoted endothelial cell migration based on scratch assay. Importantly, intramyocardial injection of the adeno-associated virus form of ETV2 into rat hearts with induced myocardial infarction designed for clinical applicability consistently resulted in significant augmentation of cardiac function. We provide compelling evidence that ETV2 has a robust effect on vascular regeneration and enhanced cardiac repair after myocardial infarction, highlighting a potential therapeutic function of ETV2 as an efficient means to treat failing hearts.


Assuntos
Infarto do Miocárdio/genética , Infarto do Miocárdio/fisiopatologia , Neovascularização Fisiológica/genética , Fatores de Transcrição/genética , Transdução Genética , Animais , Linhagem Celular , Movimento Celular , Proliferação de Células , Dependovirus/genética , Modelos Animais de Doenças , Ecocardiografia , Células Endoteliais/metabolismo , Fibroblastos/metabolismo , Fibrose , Fluordesoxiglucose F18 , Expressão Gênica , Vetores Genéticos/genética , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Tomografia por Emissão de Pósitrons , Ratos , Fatores de Transcrição/metabolismo
16.
Nanoscale ; 11(2): 431-436, 2019 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-30565636

RESUMO

Two-dimensional (2D) transition metal dichalcogenides with van der Waals gaps have attracted much attention due to their peculiarly distinctive physical properties from their bulk counterparts. Among them, vanadium diselenide (VSe2) has been considered to be a promising candidate for future spintronic devices, as room temperature ferromagnetism was reported recently. However, detailed crystallography and properties of VSe2 nanosheets have been less explored. Here, we report the atomistic real-space observation of the van der Waals layered structure of VSe2 for the first time. Furthermore, simply by controlling the carrier gas flow rate, a morphological variation of the surface area and thickness of VSe2 nanosheets was observed. The room temperature ferromagnetic feature of single VSe2 nanosheets was also revealed by magnetic force microscopy measurements. Our findings will play a significant role in the research of intrinsic 2D ferromagnetic materials.

17.
ACS Appl Mater Interfaces ; 10(49): 42875-42881, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30427172

RESUMO

Recently, attempts to overcome the physical limits of memory devices have led to the development of promising materials and architectures for next-generation memory technology. The selector device is one of the essential ingredients of high-density stacked memory systems. However, complicated constituent deposition conditions and thermal degradation are problematic, even with effective selector device materials. Herein, we demonstrate the highly stable and low-threshold voltages of vanadium pentoxide (V2O5) nanosheets synthesized by facile chemical vapor deposition, which have not been previously reported on the threshold switching (TS) properties. The electrons occupying trap sites in poly-crystalline V2O5 nanosheet contribute to the perfectly symmetric TS feature at the bias polarity and low-threshold voltages in V2O5, confirmed by high-resolution transmission electron microscopy measurements. Furthermore, we find an additional PdO interlayer in V2O5 nanodevices connected with a Pd/Au electrode after thermal annealing treatment. The PdO interlayer decreases the threshold voltages, and the Ion/ Ioff ratio increases because of the increased trap density of V2O5. These studies provide insights into V2O5 switching characteristics, which can support low power consumption in nonvolatile memory devices.

18.
Dev Reprod ; 22(3): 205-212, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30324157

RESUMO

This study is to observe the developmental process of the larval skeleton according to the growth of the trident goby, Tridentiger obscurus belonging to the larvae and juveniles and use it as the basic data of the taxonomic study. 8 days after hatching, the parasphenoid was ossified with an average total length of 3.62 mm, and basioccipital began to ossify. Caudal vertebrae and neural spine ossified in vertebra. 17 days after hatching, the average total length of the long hairs was 4.32 mm, pterotic and epiotic were ossified, and interhyal and subopercle were ossified. 52 days after hatching, the average total length of the juvenile was 18.2 mm, and lateral ethmoid, hypohyal ossified, vertebrae were parapophysis, and epural bone was osseous to the bone.

19.
Dev Reprod ; 22(1): 9-18, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29707680

RESUMO

This study was conducted to investigate the skeletal development of bullhead torrent catfish, Liobagrus obesus larvae and to utilize them as basic data for the taxonomic study of Liobagrus larvae. Skeletal development was observed by being divided into cranium, visceral skeleton, shoulder girdle bone, pelvic girdle bone and vertebra. On the first day after hatching, the pre-larvae had an average total length of 7.92 mm, and a line-shaped parasphenoid ossified in the cranium. In the jaw bone, the dentary supporting the lower jaw and the maxillary supporting the upper jaw were ossified. In the anterior abdominal vertebrae of the vertebra, seven centrums began to ossify and five neural spines ossified simultaneously. On the 3 day after hatching, pre-larvae had an average total length of 8.95 mm, and the prefrontal ossified in cranium. The number of abdominal vertebrae was increased to 14, and three parapophysis developed from the front side. On the 24th day after hatching, post-larvae had an average total length of 15.2 mm and the epural bone ossified in coccyx. The parhypural bone was ossified, and ossification of coccyx and pelvic girdle bone was completed. On the 30th day after hatching, the average total length of the juvenile was 17.8 mm, and the ossification of cranium and visceral skeleton was all completed while the preorbital and three suborbitals were ossified in the orbital region of the cranium.

20.
J Biol Chem ; 293(11): 3925-3936, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29378844

RESUMO

The stemness maintenance of embryonic stem cells (ESCs) requires pluripotency transcription factors, including Oct4, Nanog, and Sox2. We have previously reported that protein arginine methyltransferase 7 (PRMT7), an epigenetic modifier, is an essential pluripotency factor that maintains the stemness of mouse ESCs, at least in part, by down-regulating the expression of the anti-stemness microRNA (miRNA) miR-24-2. To gain greater insight into the molecular basis underlying PRMT7-mediated maintenance of mouse ESC stemness, we searched for new PRMT7-down-regulated anti-stemness miRNAs. Here, we show that miR-221 gene-encoded miR-221-3p and miR-221-5p are anti-stemness miRNAs whose expression levels in mouse ESCs are directly repressed by PRMT7. Notably, both miR-221-3p and miR-221-5p targeted the 3' untranslated regions of mRNA transcripts of the major pluripotency factors Oct4, Nanog, and Sox2 to antagonize mouse ESC stemness. Moreover, miR-221-5p silenced also the expression of its own transcriptional repressor PRMT7. Transfection of miR-221-3p and miR-221-5p mimics induced spontaneous differentiation of mouse ESCs. CRISPR-mediated deletion of the miR-221 gene, as well as specific antisense inhibitors of miR-221-3p and miR-221-5p, inhibited the spontaneous differentiation of PRMT7-depleted mouse ESCs. Taken together, these findings reveal that the PRMT7-mediated repression of miR-221-3p and miR-221-5p expression plays a critical role in maintaining mouse ESC stemness. Our results also establish miR-221-3p and miR-221-5p as anti-stemness miRNAs that target Oct4, Nanog, and Sox2 mRNAs in mouse ESCs.


Assuntos
Regulação da Expressão Gênica , MicroRNAs/genética , Células-Tronco Embrionárias Murinas/citologia , Proteína Homeobox Nanog/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Camundongos , Células-Tronco Embrionárias Murinas/metabolismo , Proteína Homeobox Nanog/genética , Fator 3 de Transcrição de Octâmero/genética , Proteína-Arginina N-Metiltransferases/genética , Fatores de Transcrição SOXB1/genética
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