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1.
ACS Appl Mater Interfaces ; 15(41): 48452-48461, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37802499

RESUMO

Ferroelectric materials with a modulable polarization extent hold promise for exploring voltage-driven neuromorphic hardware, in which direct current flow can be minimized. Utilizing a single active layer of an insulating ferroelectric polymer, we developed a voltage-mode ferroelectric synapse that can continuously and reversibly update its states. The device states are straightforwardly manifested in the form of variable output voltage, enabling large-scale direct cascading of multiple ferroelectric synapses to build a deep physical neural network. Such a neural network based on potential superposition rather than current flow is analogous to the biological counterpart driven by action potentials in the brain. A high accuracy of over 97% for the simulation of handwritten digit recognition is achieved using the voltage-mode neural network. The controlled ferroelectric polarization, revealed by piezoresponse force microscopy, turns out to be responsible for the synaptic weight updates in the ferroelectric synapses. The present work demonstrates an alternative strategy for the design and construction of emerging artificial neural networks.

2.
Cytogenet Genome Res ; 161(3-4): 167-177, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33951625

RESUMO

The barrier-to-autointegration factor (BAF) is widely expressed in most human tissues and plays a critical role in chromatin organization, nuclear envelope assembly, gonadal development, and embryonic stem cell self-renewal. Complete loss of BAF has been shown to lead to embryonic lethality and gonadal defects. The BAF paralog, namely, barrier-to-autointegration factor 2 (BANF2), exhibits a testis-predominant expression pattern in both humans and mice. Unlike BAF, it may cause isolated male infertility. Therefore, we used the CRISPR/Cas9 system to generate Banf2-knockout mice to further study its function in spermatogenesis. Unexpectedly, knockout mice did not show any detectable abnormalities in histological structure of the testis, epididymis, ovary, and other tissues, and exhibited normal fertility, indicating that Banf2 is not essential for mouse spermatogenesis and fertility.


Assuntos
Fertilidade/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Nucleares/genética , Espermatogênese/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sistemas CRISPR-Cas , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Genes Essenciais , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Nucleares/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espermatozoides/metabolismo , Testículo/citologia , Testículo/metabolismo
3.
Biomed Pharmacother ; 131: 110764, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33152927

RESUMO

OBJECTIVE: Type 2 diabetes mellitus (T2DM) is thought to be a risk factor for endometrial hyperplasia, but potential links between the two diseases are unknown. This study aims to evaluate the role of T2DM in the progression of endometrial hyperplasia. METHODS: Female Sprague-Dawley rats were randomly divided into normal (N) group, endometrial hyperplasia (NH) group, T2DM (T) group, and endometrial hyperplasia with T2DM (TH) group. Proteomics analysis was performed to determine the protein profile of endometrial tissues. Proliferation, migration, and invasion of cells with/without GLANT2-knockdown were assessed. Immunohistochemical staining and ELISA were used to examine the expression of GALNT2 in endometrial tissues and serum of clinical samples. RESULTS: The highest uterus index and endometrial thickness were observed in TH group, with the expression of proliferation marker PCNA increased significantly, indicating that T2DM facilitates the progress of endometrial hyperplasia. Proteomics analysis showed that there were significant differences in protein profiles among groups and differential proteins were mainly enriched in metabolic pathways. Further verification by molecular biology analysis indicated that GALNT2 is the key target for T2DM facilitating endometrial hyperplasia. The expression of GALNT2 was significantly decreased in high glucose environment. T2DM could synergize the proliferative function of GALNT2 aberration by activating EGFR/AKT/ERK pathway. The decreased expressions of GALNT2 in clinical samples were associated with worse subtypes of endometrial hyperplasia. CONCLUSION: T2DM promoted the progression of endometrial hyperplasia by regulating the GALNT2-mediated phosphorylation of EGFR and enhancing cell proliferation. GALNT2 has the potential to be a novel biomarker in the treatment of endometrial hyperplasia.


Assuntos
Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 2/complicações , Hiperplasia Endometrial/etiologia , Mucinas/metabolismo , N-Acetilgalactosaminiltransferases/metabolismo , Animais , Proliferação de Células/fisiologia , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Progressão da Doença , Hiperplasia Endometrial/fisiopatologia , Feminino , Técnicas de Silenciamento de Genes , Glicosilação , Fosforilação/fisiologia , Ratos , Ratos Sprague-Dawley , Polipeptídeo N-Acetilgalactosaminiltransferase
4.
Yi Chuan ; 42(6): 524-535, 2020 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-32694111

RESUMO

The structure of sperm tail is closely related to its motor function, which directly determines whether the sperm can be normally transported to fallopian tube and fertilize the ovum. The formation and development of sperm tail is a very complex process, which is finely regulated by various kinds of proteins. Research finds that defects of various sperm tail development related proteins can lead to oligospermia, asthenozoospermia and teratospermia. Based on the ultrastructure of sperm tail, we summarize the recent research progress of the proteins related to sperm tail development, thereby providing the theoretical basis and practical possibility for the diagnosis and treatment of male infertility.


Assuntos
Astenozoospermia , Cauda do Espermatozoide , Feminino , Humanos , Masculino , Maturação do Esperma , Motilidade dos Espermatozoides , Espermatozoides
5.
J Gastroenterol Hepatol ; 35(6): 1023-1031, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31788852

RESUMO

BACKGROUND: To investigate the correlation between the level of circulating vitamin D and the development of colorectal cancer (CRC) and to clarify the effect and mechanism of vitamin D on the development of CRC. METHODS: Serum samples from 63 patients with CRC (CRC group) and 61 healthy volunteers (normal group) were collected. Azoxymethane + dextran sodium sulfate-induced CRC mouse model and dietary models with different doses of vitamin D were established to verify whether vitamin D supplementation could reverse the occurrence and development of CRC at the overall animal level. Intestinal barrier integrity and microbial defense response were evaluated by detection of intestinal flora and expression of related genes. RESULTS: In the clinical serum samples, compared with the normal group, the level of 25 (OH) D3 in the CRC group was relatively low (P < 0.01), which was consistent with the clinical situation in mice. Vitamin D deficiency aggravated the deterioration of enteritis and intestinal cancer in CRC mice, whereas the overall condition of CRC mice improved after vitamin D supplementation. Vitamin D has a significant regulatory effect on the homeostasis of the intestinal flora, particularly in the regulation of intestinal probiotics, Akkermansia muciniphila-mediated colon barrier integrity. CONCLUSIONS: Vitamin D deficiency is closely related to the high incidence of CRC, and vitamin D supplementation can inhibit the occurrence and development of CRC. Vitamin D plays a role in the reversal of CRC mainly through the regulation of intestinal flora, especially the regulation of A. muciniphila-mediated colon barrier integrity.


Assuntos
Neoplasias Colorretais/etiologia , Neoplasias Colorretais/microbiologia , Neoplasias Colorretais/prevenção & controle , Microbioma Gastrointestinal/efeitos dos fármacos , Deficiência de Vitamina D/complicações , Vitamina D/administração & dosagem , Vitamina D/farmacologia , Akkermansia , Animais , Suplementos Nutricionais , Modelos Animais de Doenças , Humanos , Masculino , Camundongos Endogâmicos C57BL , Verrucomicrobia
6.
ACS Appl Mater Interfaces ; 11(43): 40366-40371, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31595743

RESUMO

Integration of selective photodetection and signal storage in a single device, such as organic field-effect transistor (OFET) memories, meets the demands for radiation monitoring and protection. A new strategy is developed to achieve filter-free and selective light monitoring by adopting a solution-processed blend charge-trapping layer in OFET memories, where the charge-trapping layer is composed of phenyl-C61-butyric acid methyl ester (PCBM) dispersed in a polymer electret thin film. The OFET memory without PCBM shows response only to ultraviolet light, whereas the spectral response edges are extended to the visible and near-infrared regions in the corresponding devices with relatively low and high contents of PCBM in the charge-trapping layer, respectively. A set of OFET memories with different PCBM contents is used to qualitatively evaluate the light composition in an optical source. The tunable spectral response in the OFET memories is ascribed to the additional photoassisted charge-trapping paths depending on the blend ratio in the charge-trapping layer. This mechanism may inspire alternative approaches to organic-based optical sensing and monitoring in flexible and wearable electronics.

7.
RSC Adv ; 8(36): 20182-20189, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35541635

RESUMO

Finding earth-abundant and high-performance electrode materials for supercapacitors is a demanding challenge in the energy storage field. Cuprous oxide (Cu2O) has attracted increasing attention due to its theoretically high specific capacitance, however, the development of Cu2O-based electrodes with superior capacitive performance is still challenging. We herein report a simple and effective ionic-liquid-assisted sputtering approach to synthesizing the Cu2O nanoparticles/multi-walled carbon nanotubes (Cu2O/MWCNTs) nanocomposite for high-performance asymmetric supercapacitors. The Cu2O/MWCNTs nanocomposite delivers a high specific capacitance of 357 F g-1, good rate capability and excellent capacitance retention of about 89% after 20 000 cycles at a current density of 10 A g-1. The high performance is attributed to the uniform dispersion of small-sized Cu2O nanoparticles on conductive MWCNTs, which offers plenty of redox active sites and thus improve the electron transfer efficiency. Oxygen vacancies are further introduced into Cu2O by the NaBH4 treatment, providing the oxygen-deficient Cu2O/MWCNTs (r-Cu2O/MWCNTs) nanocomposite with significantly improved specific capacitance (790 F g-1) and cycling stability (∼93% after 20 000 cycles). The assembled asymmetric supercapacitor based on the r-Cu2O/MWCNTs//activated carbon (AC) structure achieves a high energy density of 64.2 W h kg-1 at 825.3 W kg-1, and long cycling life. This work may form a foundation for the development of both high capacity and high energy density supercapacitors by showcasing the great potential of earth-abundant Cu-based electrode materials.

8.
Nanomicro Lett ; 9(4): 48, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30393743

RESUMO

We present a straightforward physical approach for synthesizing multiwalled carbon nanotubes (CNTs)-PdAu/Pt trimetallic nanoparticles (NPs), which allows predesign and control of the metal compositional ratio by simply adjusting the sputtering targets and conditions. The small-sized CNTs-PdAu/Pt NPs (~3 nm, Pd/Au/Pt ratio of 3:1:2) act as nanocatalysts for the methanol oxidation reaction (MOR), showing excellent performance with electrocatalytic peak current of 4.4 A mgPt -1 and high stability over 7000 s. The electrocatalytic activity and stability of the PdAu/Pt trimetallic NPs are much superior to those of the corresponding Pd/Pt and Au/Pt bimetallic NPs, as well as a commercial Pt/C catalyst. Systematic investigation of the microscopic, crystalline, and electronic structure of the PdAu/Pt NPs reveals alloying and charge redistribution in the PdAu/Pt NPs, which are responsible for the promotion of the electrocatalytic performance.

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