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1.
Nat Immunol ; 20(1): 18-28, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30510222

RESUMO

Cyclic GMP-AMP synthase (cGAS) is a key sensor responsible for cytosolic DNA detection. Here we report that GTPase-activating protein SH3 domain-binding protein 1 (G3BP1) is critical for DNA sensing and efficient activation of cGAS. G3BP1 enhanced DNA binding of cGAS by promoting the formation of large cGAS complexes. G3BP1 deficiency led to inefficient DNA binding by cGAS and inhibited cGAS-dependent interferon (IFN) production. The G3BP1 inhibitor epigallocatechin gallate (EGCG) disrupted existing G3BP1-cGAS complexes and inhibited DNA-triggered cGAS activation, thereby blocking DNA-induced IFN production both in vivo and in vitro. EGCG administration blunted self DNA-induced autoinflammatory responses in an Aicardi-Goutières syndrome (AGS) mouse model and reduced IFN-stimulated gene expression in cells from a patient with AGS. Thus, our study reveals that G3BP1 physically interacts with and primes cGAS for efficient activation. Furthermore, EGCG-mediated inhibition of G3BP1 provides a potential treatment for cGAS-related autoimmune diseases.


Assuntos
Doenças Autoimunes do Sistema Nervoso/metabolismo , DNA Helicases/metabolismo , Complexos Multiproteicos/metabolismo , Malformações do Sistema Nervoso/metabolismo , Nucleotidiltransferases/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Animais , Autoantígenos/imunologia , Autoantígenos/metabolismo , Doenças Autoimunes do Sistema Nervoso/tratamento farmacológico , Doenças Autoimunes do Sistema Nervoso/genética , Catequina/análogos & derivados , Catequina/uso terapêutico , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Citosol/imunologia , Citosol/metabolismo , DNA/imunologia , DNA/metabolismo , DNA Helicases/antagonistas & inibidores , DNA Helicases/genética , Modelos Animais de Doenças , Exodesoxirribonucleases/genética , Células HEK293 , Células HeLa , Humanos , Interferons/metabolismo , Camundongos , Camundongos Knockout , Malformações do Sistema Nervoso/tratamento farmacológico , Malformações do Sistema Nervoso/genética , Fármacos Neuroprotetores/uso terapêutico , Fosfoproteínas/genética , Proteínas de Ligação a Poli-ADP-Ribose/antagonistas & inibidores , Proteínas de Ligação a Poli-ADP-Ribose/genética , Ligação Proteica , RNA Helicases/antagonistas & inibidores , RNA Helicases/genética , Proteínas com Motivo de Reconhecimento de RNA/antagonistas & inibidores , Proteínas com Motivo de Reconhecimento de RNA/genética
2.
Arterioscler Thromb Vasc Biol ; 44(3): 533-544, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38235555

RESUMO

Both hyperlipidemia and thrombosis contribute to the risks of atherosclerotic cardiovascular diseases, which are the leading cause of death and reduced quality of life in survivors worldwide. The accumulation of lipid-rich plaques on arterial walls eventually leads to the rupture or erosion of vulnerable lesions, triggering excessive blood clotting and leading to adverse thrombotic events. Lipoproteins are highly dynamic particles that circulate in blood, carry insoluble lipids, and are associated with proteins, many of which are involved in blood clotting. A growing body of evidence suggests a reciprocal regulatory relationship between blood clotting and lipid metabolism. In this review article, we summarize the observations that lipoproteins and lipids impact the hemostatic system, and the clotting-related proteins influence lipid metabolism. We also highlight the gaps that need to be filled in this area of research.


Assuntos
Aterosclerose , Trombose , Humanos , Qualidade de Vida , Coagulação Sanguínea , Aterosclerose/patologia , Fatores de Coagulação Sanguínea , Lipoproteínas , Fibrinólise
3.
Mol Ther ; 32(1): 204-217, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37952086

RESUMO

Inner ear hair cells detect sound vibration through the deflection of mechanosensory stereocilia. Cytoplasmic protein TPRN has been shown to localize at the taper region of the stereocilia, and mutations in TPRN cause hereditary hearing loss through an unknown mechanism. Here, using biochemistry and dual stimulated emission depletion microscopy imaging, we show that the TPRN, together with its binding proteins CLIC5 and PTPRQ, forms concentric rings in the taper region of stereocilia. The disruption of TPRN rings, triggered by the competitive inhibition of the interaction of TPRN and CLIC5 or exogenous TPRN overexpression, leads to stereocilia degeneration and severe hearing loss. Most importantly, restoration of the TPRN rings can rescue the damaged auditory function of Tprn knockout mice by exogenously expressing TPRN at an appropriate level in HCs via promoter recombinant adeno-associated virus (AAV). In summary, our results reveal highly structured TPRN rings near the taper region of stereocilia that are crucial for stereocilia function and hearing. Also, TPRN ring restoration in stereocilia by AAV-Tprn effectively repairs damaged hearing, which lays the foundation for the clinical application of AAV-mediated gene therapy in patients with TPRN mutation.


Assuntos
Surdez , Perda Auditiva , Animais , Humanos , Camundongos , Surdez/genética , Audição/genética , Perda Auditiva/genética , Perda Auditiva/terapia , Camundongos Knockout , Proteínas/metabolismo , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/metabolismo , Estereocílios/metabolismo
4.
Hum Mol Genet ; 31(15): 2595-2605, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35288736

RESUMO

Prior studies have shown that genetic factors play important roles in ovarian endometriosis. Herein, we first analyzed the whole-exome sequencing data from 158 patients with ovarian endometriosis and 385 local control women without endometriosis. Among which, a rare missense variant in the MMP7 (p.I79T, rs150338402) gene exhibited a significant frequency difference. This rare variant was screened in an additional 1176 patients and 600 control women via direct DNA sequencing. Meanwhile, a total of 38 available clinical characteristics were collected. Our results showed 45 out of 1334 (3.37%) patients, while 15 out of 985 control women (1.52%) (P = 0.0076) harbored this rare variant, respectively. This rare variant was associated with clinical features such as follicle-stimulating hormone (Padj = 0.0342), luteinizing hormone (Padj = 0.0038), progesterone (Padj = 1.4e-7), testosterone (Padj = 0.0923), total bilirubin (Padj = 0.0699), carcinoembryonic antigen (Padj = 0.0665) and squamous cell carcinoma antigen (Padj = 0.0817), respectively. Functional assays showed that this rare variant could promote cell migration, invasion, epithelial-mesenchymal transition (EMT) and increase the proteolytic protein activity of MMP7, implicating that the increased capacities of cell invasion, migration and EMT might be mediated by enhanced proteolytic activity of MMP7 mutant. These results showed that the MMP7 rare missense variant (p.I79T) played important roles in the pathogenesis of ovarian endometriosis. In conclusion, we identified, for the first time, a significantly enriched MMP7 rare variant in ovarian endometriosis; this rare variant was closely associated with certain clinical features in ovarian endometriosis; thus, it could be a promising early diagnostic biomarker for this disease.


Assuntos
Endometriose , Metaloproteinase 7 da Matriz/genética , Neoplasias Ovarianas , Endometriose/genética , Transição Epitelial-Mesenquimal , Feminino , Humanos , Metaloproteinase 7 da Matriz/metabolismo , Mutação de Sentido Incorreto/genética , Neoplasias Ovarianas/patologia , Sequenciamento do Exoma
5.
Apoptosis ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38824477

RESUMO

The upregulation of programmed death ligand 1 (PD-L1) plays a crucial role in facilitating cancer cells to evade immune surveillance through immunosuppression. However, the precise regulatory mechanisms of PD-L1 in hepatocellular carcinoma (HCC) remain undefined. The correlation between PD-L1 and ubiquitin-like molecules (UBLs) was studied using sequencing data from 20 HCC patients in our center, combined with TCGA data. Specifically, the association between FAT10 and PD-L1 was further validated at both the protein and mRNA levels in HCC tissues from our center. Subsequently, the effect of FAT10 on tumor progression and immune suppression was examined through both in vivo and in vitro experiments. Utilizing sequencing data, qPCR, and Western blotting assays, we confirmed that FAT10 was highly expressed in HCC tissues and positively correlated with PD-L1 expression. Additionally, in vitro experiments demonstrated that the overexpression of FAT10 fostered the proliferation, migration, and invasion of HCC cells. Furthermore, the overexpression of FAT10 in HCC cells led to an increase in PD-L1 expression, resulting in the inhibition of T cell proliferation and the enhancement of HCC cell resistance to T cell-mediated cytotoxicity. Moreover, in vivo experiments utilizing the C57BL/6 mouse model revealed that overexpression of FAT10 effectively suppressed the infiltration of CD8 + GZMB + and CD8 + Ki67 + T cells, as well as reduced serum levels of TNF-α and IFN-γ. Mechanistically, we further identified that FAT10 upregulates PD-L1 expression via activating the PI3K/AKT/mTOR pathway, but not in a ubiquitin-like modification. In conclusion, our findings indicate that FAT10 promotes immune evasion of HCC via upregulating PD-L1 expression, suggesting its potential as a novel target to enhance the efficiency of immunotherapy in HCC.

6.
Fungal Genet Biol ; : 103911, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960372

RESUMO

Coprinopsis cinerea, a model fungus, is utilized for investigating the developmental mechanisms of basidiomycetes. The development of basidiomycetes is a highly organized process that requires coordination among genetic, environmental, and physiological factors. Oxylipins, a class of widely distributed signaling molecules, play crucial roles in fungal biology. Among oxylipins, the sexual pheromone-inducing factors (psi factors) have been identified as key regulators of the balance between asexual and sexual spore development in Ascomycetes. Linoleate dioxygenases are enzymes involved in the biosynthesis of psi factors, yet their specific physiological functions in basidiomycete development remain unclear. In this study, linoleate dioxygenases in basidiomycetes were identified and characterized. Phylogenetic analysis revealed that linoleate dioxygenases from Basidiomycota formed a distinct clade, with linoleate dioxygenases from Agaricomycetes segregating into three groups and those from Ustilaginomycetes forming a separate group. Both basidiomycete and ascomycete linoleate dioxygenases shared two characteristic domains: the N-terminal of linoleate dioxygenase domain and the C-terminal of cytochrome P450 domain. While the linoleate dioxygenase domains exhibited similarity between basidiomycetes and ascomycetes, the cytochrome P450 domains displayed high diversity in key sites. Furthermore, the gene encoding the linoleate dioxygenase Ccldo1 in C. cinerea was knocked out, resulting in a significant increase in fruiting body formation without affecting asexual conidia production. This observation suggests that secondary metabolites synthesized by CcLdo1 negatively regulate the sexual reproduction process in C. cinerea while not influencing the asexual reproductive process. This study represents the first identification of a gene involved in secondary metabolite synthesis that regulates basidiocarp development in a basidiomycete.

7.
Opt Express ; 32(11): 18858-18870, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859033

RESUMO

A universally applicable approach is proposed for the fabrication of fiber-optic polymer sensors. The hollow-core fibers (HCFs) with inner diameters of 30 µm, 50 µm, and 75 µm are spliced coaxially with dual-hole fiber (DHF) or photonic crystal fiber (PCF). Owing to the sized-matched air holes within HCF and DHF/PCF, an interconnected in-fiber microchannel is constructed, which facilitates rapid and complete filling of the HCF's central hole with liquid glue. After the ultraviolet-induced polymerization, a polymer Fabry-Perot interferometer is achieved by cutting the HCF end with a desired cavity length. Besides, the interference visibility is significantly enhanced by adding a refractive-index-modulated polymer cap onto the cutting surface. Experimental results demonstrate the optimized interference spectra and the interconnection of the matched air-hole fibers. The polymer sensor exhibits a signal-to-noise ratio of 56.8 dB for detecting pulsed ultrasonic waves, which is more than twice that of a partially polymer-filled sensor. Due to the hermetically-sealed structure, the sensor probe presents constrained performance with a temperature sensitivity of 230.2 pm/°C and a humidity sensitivity of 93.7 pm/%RH, which can be further improved by releasing the polymer waveguide from fiber cladding. Based on interconnected holey fibers, the proposed approach has a uniform size-controlled polymer waveguide dimension with increased spectrum visibility, rendering it suitable for a diverse range of microstructure-matched optical fibers.

8.
FASEB J ; 37(3): e22802, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36786696

RESUMO

Recurrent spontaneous abortion (RSA) is characterized by two or more consecutive pregnancy losses in the first trimester of pregnancy, experienced by 5% of women during their reproductive age. As a complex pathological process, the etiology of RSA remains poorly understood. Recent studies have established that gene expression changes dramatically in human endometrial stromal cells (ESCs) during decidualization. N6-methyladenosine (m6 A) modification is the most prevalent epigenetic modification of mRNA in eukaryotic cells and it is closely related to the occurrence and development of many pathophysiological phenomena. In this study, we first confirmed that high levels of m6 A mRNA methylation in decidual tissues are associated with RSA. Then, we used m6 A-modified RNA immunoprecipitation sequence (m6 A-seq) and RNA sequence (RNA-seq) to identify the differentially expressed m6 A methylation in decidual tissues from RSA patients and identified the key genes involved in abnormal decidualization by bioinformatics analysis. Using m6 A-seq, we identified a total of 2169 genes with differentially expressed m6 A methylation, of which 735 m6 A hypermethylated genes and 1434 m6 A hypomethylated genes were identified. Further joint analysis of m6 A-seq and RNA-seq revealed that 133 genes were m6 A modified with mRNA expression. GO and KEGG analyses indicated that these unique genes were mainly enriched in environmental information processing pathways, including the cytokine-cytokine receptor interaction and PI3K-Akt signaling pathway. In summary, this study uncovered the transcriptome-wide m6 A modification pattern in decidual tissue of RSA, which provides a theoretical basis for further research into m6 A modification and new therapeutic strategies for RSA.


Assuntos
Aborto Habitual , Fosfatidilinositol 3-Quinases , Gravidez , Humanos , Feminino , Metilação , Transcriptoma , Adenosina/genética
9.
Neurochem Res ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916813

RESUMO

Dysfunction of Schwann cells, including cell apoptosis, autophagy inhibition, dedifferentiation, and pyroptosis, is a pivotal pathogenic factor in induced diabetic peripheral neuropathy (DPN). Histone deacetylases (HDACs) are an important family of proteins that epigenetically regulate gene transcription by affecting chromatin dynamics. Here, we explored the effect of HDAC1 on high glucose-cultured Schwann cells. HDAC1 expression was increased in diabetic mice and high glucose-cultured RSC96 cells, accompanied by cell apoptosis. High glucose also increased the mitochondrial pathway apoptosis-related Bax/Bcl-2 and cleaved caspase-9/caspase-9 ratios and decreased endoplasmic reticulum response-related GRP78, CHOP, and ATF4 expression in RSC96 cells (P < 0.05). Furthermore, overexpression of HDAC1 increased the ratios of Bax/Bcl-2, cleaved caspase-9/caspase-9, and cleaved caspase-3 and reduced the levels of GRP78, CHOP, and ATF4 in RSC96 cells (P < 0.05). In contrast, knockdown of HDAC1 inhibited high glucose-promoted mitochondrial pathway apoptosis and suppressed the endoplasmic reticulum response. Moreover, RNA sequencing revealed that U4 spliceosomal RNA was significantly reduced in HDAC1-overexpressing RSC96 cells. Silencing of U4 spliceosomal RNA led to an increase in Bax/Bcl-2 and cleaved caspase-9 and a decrease in CHOP and ATF4. Conversely, overexpression of U4 spliceosomal RNA blocked HDAC1-promoted mitochondrial pathway apoptosis and inhibited the endoplasmic reticulum response. In addition, alternative splicing analysis of HDAC1-overexpressing RSC96 cells showed that significantly differential intron retention (IR) of Rpl21, Cdc34, and Mtmr11 might be dominant downstream targets that mediate U4 deficiency-induced Schwann cell dysfunction. Taken together, these findings indicate that HDAC1 promotes mitochondrial pathway-mediated apoptosis and inhibits the endoplasmic reticulum stress response in high glucose-cultured Schwann cells by decreasing the U4 spliceosomal RNA/IR of Rpl21, Cdc34, and Mtmr11.

10.
Cell Mol Life Sci ; 80(4): 86, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36917323

RESUMO

Mechanosensitive hair cells (HCs) in the cochlear sensory epithelium are critical for sound detection and transduction. Mammalian HCs in the cochlea undergo cytogenesis during embryonic development, and irreversible damage to hair cells postnatally is a major cause of deafness. During the development of the organ of Corti, HCs and supporting cells (SCs) originate from the same precursors. In the neonatal cochlea, damage to HCs activates adjacent SCs to act as HC precursors and to differentiate into new HCs. However, the plasticity of SCs to produce new HCs is gradually lost with cochlear development. Here, we delineate an essential role for the guanine nucleotide exchange factor Net1 in SC trans-differentiation into HCs. Net1 overexpression mediated by AAV-ie in SCs promoted cochlear organoid formation and HC differentiation under two and three-dimensional culture conditions. Also, AAV-Net1 enhanced SC proliferation in Lgr5-EGFPCreERT2 mice and HC generation as indicated by lineage tracing of HCs in the cochleae of Lgr5-EGFPCreERT2/Rosa26-tdTomatoloxp/loxp mice. We further found that the up-regulation of Wnt/ß-catenin and Notch signaling in AAV-Net1-transduced cochleae might be responsible for the SC proliferation and HC differentiation. Also, Net1 overexpression in SCs enhanced SC proliferation and HC regeneration and survival after HC damage by neomycin. Taken together, our study suggests that Net1 might serve as a potential target for HC regeneration and that AAV-mediated gene regulation may be a promising approach in stem cell-based therapy in hearing restoration.


Assuntos
Transdiferenciação Celular , Células Ciliadas Auditivas , Animais , Camundongos , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Cóclea , Camundongos Transgênicos
11.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34260378

RESUMO

Centrosome duplication and DNA replication are two pivotal events that higher eukaryotic cells use to initiate proliferation. While DNA replication is initiated through origin licensing, centrosome duplication starts with cartwheel assembly and is partly controlled by CP110. However, the upstream coordinator for both events has been, until now, a mystery. Here, we report that suppressor of fused protein (Sufu), a negative regulator of the Hedgehog (Hh) pathway playing a significant role in restricting the trafficking and function of glioma-related (Gli) proteins, acts as an upstream switch by facilitating CP110 phosphorylation by CDK2, promoting intranuclear Cdt1 degradation and excluding prereplication complex (pre-RC) components from chromosomes, independent of its canonical function in the Hh pathway. We found that Sufu localizes to both the centrosome and the nucleus and that knockout of Sufu induces abnormalities including centrosome amplification, increased nuclear size, multipolar spindle formation, and polyploidy. Serum stimulation promotes the elimination of Sufu from the centrosome by vesicle release at the ciliary tip and from the nucleus via protein degradation, which allows centrosome duplication and DNA replication to proceed. Collectively, this work reveals a mechanism through which Sufu negatively regulates the G1-S transition.


Assuntos
Centrossomo/metabolismo , Replicação do DNA , Proteínas Repressoras/metabolismo , Animais , Proteínas de Ligação a Calmodulina/metabolismo , Proteínas de Ciclo Celular/metabolismo , Morte Celular , Núcleo Celular/metabolismo , Cílios/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Vesículas Citoplasmáticas/metabolismo , Fibroblastos/metabolismo , Fase G1 , Células HEK293 , Células HeLa , Proteínas Hedgehog/metabolismo , Humanos , Camundongos , Mitose , Mutação/genética , Fosforilação , Proteólise , Proteínas Repressoras/genética , Fase S
12.
Behav Res Methods ; 56(3): 2581-2594, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37528294

RESUMO

Affective picture databases with a single facial expression or body posture in one image have been widely applied to investigate emotion. However, to date, there was no standardized database containing the stimuli which involve multiple emotional signals in social interactive scenarios. The current study thus developed a pictorial set comprising 274 images depicting two Chinese adults' interactive scenarios conveying emotions of happiness, anger, sadness, fear, disgust, and neutral. The data of the valence and arousal ratings of the scenes and the emotional categories of the scenes and the faces in the images were provided in the present study. Analyses of the data collected from 70 undergraduate students suggested high reliabilities of the valence and arousal ratings of the scenes and high judgmental agreements in categorizing the scene and facial emotions. The findings suggested that the present dataset is well constructed and could be useful for future studies to investigate the emotion recognition or empathy in social interactions in both healthy and clinical (e.g., ASD) populations.


Assuntos
Emoções , Felicidade , Adulto , Humanos , Ira , Medo , Expressão Facial , China
13.
Angew Chem Int Ed Engl ; 63(20): e202402657, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477874

RESUMO

The main group metals are commonly perceived as catalytically inert in the context of oxygen reduction reactions (ORR) due to the delocalized valence orbitals. Regulating the local environment and structure of metal center coordinated by nitrogen ligands (M-Nx) is a promising approach to accelerate catalytic dynamics. Herein, we, for the first time, report the atomically dispersed Al catalysts coordinated with N and C atoms for 4-electron ORR. The axial coordinated pyrrolyl N group (No) is constructed in the Al-N4-No moiety to regulate the p-band structure of Al center, effectively steering the local environment and structure of the square planar Al-N4 sites, which typically exhibit too strong interaction with ORR intermediates. The dynamic covalency competition of axial Al-No and Al-O bonding could endow the Al center with moderate hybridization between Al 3p orbital and O 2p orbital, alleviating the binding energy of ORR intermediates. The as-prepared Al-N4-No electrocatalyst exhibits excellent ORR activity, selectivity, and durability, along with the rapid kinetics as demonstrated by in situ Raman spectroscopy. This work offers a fundamental comprehension of the fine regulation on p-band and guides the rational design of main-group metal-based single atom catalysts.

14.
Angew Chem Int Ed Engl ; 63(15): e202400577, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38284909

RESUMO

Atomically dispersed metal-nitrogen-carbon (M-N-C) catalysts have exhibited encouraging oxygen reduction reaction (ORR) activity. Nevertheless, the insufficient long-term stability remains a widespread concern owing to the inevitable 2-electron byproducts, H2O2. Here, we construct Co-N-Cr cross-interfacial electron bridges (CIEBs) via the interfacial electronic coupling between Cr2O3 and Co-N-C, breaking the activity-stability trade-off. The partially occupied Cr 3d-orbitals of Co-N-Cr CIEBs induce the electron rearrangement of CoN4 sites, lowering the Co-OOH* antibonding orbital occupancy and accelerating the adsorption of intermediates. Consequently, the Co-N-Cr CIEBs suppress the two-electron ORR process and approach the apex of Sabatier volcano plot for four-electron pathway simultaneously. As a proof-of-concept, the Co-N-Cr CIEBs is synthesized by the molten salt template method, exhibiting dominant 4-electron selectively and extremely low H2O2 yield confirmed by Damjanovic kinetic analysis. The Co-N-Cr CIEBs demonstrates impressive bifunctional oxygen catalytic activity (▵E=0.70 V) and breakthrough durability including 100 % current retention after 10 h continuous operation and cycling performance over 1500 h for Zn-air battery. The hybrid interfacial configuration and the understanding of the electronic coupling mechanism reported here could shed new light on the design of superdurable M-N-C catalysts.

15.
Nat Mater ; 21(12): 1403-1411, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36411348

RESUMO

To realize molecular-scale electrical operations beyond the von Neumann bottleneck, new types of multifunctional switches are needed that mimic self-learning or neuromorphic computing by dynamically toggling between multiple operations that depend on their past. Here, we report a molecule that switches from high to low conductance states with massive negative memristive behaviour that depends on the drive speed and number of past switching events, with all the measurements fully modelled using atomistic and analytical models. This dynamic molecular switch emulates synaptic behavior and Pavlovian learning, all within a 2.4-nm-thick layer that is three orders of magnitude thinner than a neuronal synapse. The dynamic molecular switch provides all the fundamental logic gates necessary for deep learning because of its time-domain and voltage-dependent plasticity. The synapse-mimicking multifunctional dynamic molecular switch represents an adaptable molecular-scale hardware operable in solid-state devices, and opens a pathway to simplify dynamic complex electrical operations encoded within a single ultracompact component.


Assuntos
Eletricidade
16.
Cell Mol Biol (Noisy-le-grand) ; 69(5): 156-162, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37571887

RESUMO

Numerous studies have proved that epithelial-mesenchymal transition (EMT) of lung epithelial cells is one of the important causes of radiation-induced pulmonary fibrosis (RIPF). Aldose reductase (AR) is a monomer enzyme in the polyglycolic metabolic pathway and belongs to the aldo-keno reductase protein superfamily. Our previous studies have found that AR as one of the most significantly up-regulated genes was associated with the development of bleomycin-induced PF in rats. It is not clear whether aldose reductase is related to the regulation of radiation-induced EMT and mediates RIPF. AR-knockout mice, wild-type mice and lung epithelial cells were induced by radiation to establish a RIPF animal model and EMT system, to explore whether AR is mediation to RIPF through the EMT pathway. In vivo, AR deficiency significantly alleviated radiation-induced histopathological changes, reduced collagen deposition and inhibited collagen I, matrix metalloproteinase 2 (MMP2) and Twist1 expression. In addition, AR knockout up-regulated E-cadherin expression and up-regulated α-SMA and Vimentin expression. In vitro, AR, collagen I and MMP2 expression were increased in lung epithelial cells after radiation, which was accompanied by Twist1 expression up-regulation and EMT changes evidenced by decreased E-cadherin expression and increased α-SMA and Vimentin expression. Knockdown or inhibition of AR inhibited the expressions of Twist1, MMP2 and collagen I, and reduced cell migration and reversed radiation-induced EMT. These results indicated that aldose reductase may be related to radiation-induced lung epithelial cells EMT, and that inhibition of aldose reductase might be a promising treatment for RIPF.


Assuntos
Fibrose Pulmonar , Camundongos , Ratos , Animais , Fibrose Pulmonar/genética , Fibrose Pulmonar/induzido quimicamente , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Vimentina/metabolismo , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Pulmão/patologia , Colágeno/genética , Colágeno/metabolismo , Caderinas/genética , Caderinas/metabolismo , Transição Epitelial-Mesenquimal/genética
17.
Plant Cell Rep ; 43(1): 4, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38117314

RESUMO

KEY MESSAGE: The leaf hyponasty response depends on tip-to-petiole auxin transport. This transport can happen through two parallel pathways: active trans-membrane transport mediated by PIN proteins and passive diffusion through plasmodesmata. A plant's ability to counteract potential shading by neighboring plants depends on transport of the hormone auxin. Neighbor sensing at the leaf tip triggers auxin production. Once this auxin reaches the abaxial petiole epidermis, it causes cell elongation, which leads to leaf hyponasty. Two pathways are known to contribute to this intercellular tip-to-petiole auxin movement: (i) transport facilitated by plasma membrane-localized PIN auxin transporters and (ii) diffusion enabled by plasmodesmata. We tested if these two modes of transport are arranged sequentially or in parallel. Moreover, we investigated if they are functionally linked. Mutants in which one of the two pathways is disrupted indicated that both pathways are necessary for a full hyponasty response. Visualization of PIN3-GFP and PIN7-GFP localization indicated PIN-mediated transport in parallel to plasmodesmata-mediated transport along abaxial midrib epidermis cells. We found plasmodesmata-mediated cell coupling in the pin3pin4pin7 mutant to match wild-type levels, indicating no redundancy between pathways. Similarly, PIN3, PIN4 and PIN7 mRNA levels were unaffected in a mutant with disrupted plasmodesmata pathway. Our results provide mechanistic insight on leaf hyponasty, which might facilitate the manipulation of the shade avoidance response in crops.


Assuntos
Arabidopsis , Arabidopsis/genética , Plasmodesmos , Transporte Biológico , Proteínas de Membrana Transportadoras/genética , Ácidos Indolacéticos
18.
Appl Opt ; 62(1): 178-182, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36606863

RESUMO

Contactless integrated photonic probes (CLIPPs) have been used as on-chip power monitors with minimum perturbations to optical modes. In this work, we present the experimental measurements and analysis of the noise properties of these types of devices integrated with silicon waveguides. We focus on the study of how circuitry parameters, including the gain of the trans-impedance amplifier, lock-in bandwidth, and amplitude and frequency of the bias voltage, affect the noise properties. Finally, we establish a circuit model and use the Simulation Program with Integrated Circuit Emphasis to model and simulate the noise properties of these devices. Our analysis shows that the thermal noise of the CLIPPs and electrical noise of the trans-impedance amplifier are the dominant sources of noise.

19.
Int J Mol Sci ; 24(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37511315

RESUMO

2'-fucosyllactose (2'FL) is an important nutrient in human milk that stimulates beneficial microbiota and prevents infection. α-L-fucosidase is a promising component for 2'FL synthesis. In this study, a soil-oriented α-L-fucosidase-producing strain from Enterococcus gallinarum ZS1 was isolated. Escherichia coli was employed as a host for cloning and expressing the α-L-fucosidase gene (entfuc). The EntFuc was predicted as a member of the GH29 family with a molecular mass of 58 kDa. The optimal pH and temperature for the activity of EntFuc were pH 7.0 and 30 °C, respectively. The enzyme exhibited a strictly specific activity for 4-Nitrophenyl-α-L-fucopyranoside (pNP-Fuc) and had a negligible effect on hydrolyzing 2'FL. EntFuc could catalyze the synthesis of 2'FL via transfucosylation action from pNP-Fuc and lactose. The yield of 2'FL reached 35% under optimal conditions. This study indicated that EntFuc with a high conversion rate is a promising enzyme source for the biosynthesis of 2'FL.


Assuntos
Oligossacarídeos , alfa-L-Fucosidase , Humanos , alfa-L-Fucosidase/genética , Trissacarídeos , Leite Humano/química , Escherichia coli
20.
Entropy (Basel) ; 25(5)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37238560

RESUMO

With the development of the Internet, it is more convenient for people to obtain information, which also facilitates the spread of rumors. It is imperative to study the mechanisms of rumor transmission to control the spread of rumors. The process of rumor propagation is often affected by the interaction of multiple nodes. To reflect higher-order interactions in rumor-spreading, hypergraph theories are introduced in a Hyper-ILSR (Hyper-Ignorant-Lurker-Spreader-Recover) rumor-spreading model with saturation incidence rate in this study. Firstly, the definition of hypergraph and hyperdegree is introduced to explain the construction of the model. Secondly, the existence of the threshold and equilibrium of the Hyper-ILSR model is revealed by discussing the model, which is used to judge the final state of rumor propagation. Next, the stability of equilibrium is studied by Lyapunov functions. Moreover, optimal control is put forward to suppress rumor propagation. Finally, the differences between the Hyper-ILSR model and the general ILSR model are shown in numerical simulations.

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