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1.
Opt Express ; 32(11): 19424-19437, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859077

RESUMO

Optical encryption methods, due to their efficient operation speed and parallel processing capabilities, hold significant importance in securing multidimensional and large-volume data. Enhancing the security of optical cryptosystems from the perspective of cryptanalysis holds significant importance currently. Presently, attack methods against optical encryption are complex, and the effectiveness of these attacks is insufficient. Security analysis solutions face limitations in both breadth and depth. Therefore, this paper proposes an attack on optical cryptosystems based on a skip connection network, demonstrating the susceptibility of optical cryptosystems to attacks based on neural network algorithms. The network model is trained on plaintext-ciphertext pairs, fitting equivalent keys without various additional conditions. It approximates plaintext information in high-dimensional space, directly obtaining corresponding plaintext through ciphertext information, expanding the applicability and enhancing the effectiveness of the attack scheme. Finally, the feasibility and effectiveness of the attack scheme were verified through computer simulations. The experiments indicate that the method proposed in this paper has low computational complexity, wide applicability, produces high-quality decrypted images, and high decipherment accuracy. This provides a universal approach for analyzing the security of various optical cryptosystems from the perspective of chosen plaintext attacks.

2.
Appl Microbiol Biotechnol ; 108(1): 88, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38194134

RESUMO

Mildew poses a significant threat to tobacco production; however, there is limited information on the structure of the abundant and rare microbial subcommunities in moldy tobacco leaves. In this study, we employed high-throughput sequencing technology to discern the disparities in the composition, diversity, and co-occurrence patterns of abundant and rare fungal and bacterial subcommunities between moldy and normal tobacco leaves collected from Guizhou, Shanghai, and Jilin provinces, China. Furthermore, we explored the correlation between microorganisms and metabolites by integrating the metabolic profiles of moldy and normal tobacco leaves. The results showed that the fungi are more sensitive to mildew than bacteria, and that the fungal abundant taxa exhibit greater resistance and environmental adaptability than the rare taxa. The loss of rare taxa results in irreversible changes in the diversity, richness, and composition of the fungal community. Moreover, rare fungal taxa and abundant bacterial taxa played crucial roles in maintaining the stability and functionality of the tobacco microecosystem. In moldy tobacco, however, the disappearance of rare taxa as key nodes resulted in reduced connectivity and stability within the fungal network. In addition, metabolomic analysis showed that the contents of indoles, pyridines, polyketones, phenols, and peptides were significantly enriched in the moldy tobacco leaves, while the contents of amino acids, carbohydrates, lipids, and other compounds were significantly reduced in these leaves. Most metabolites showed negative correlations with Dothideomycetes, Alphaproteobacteria, and Gammaproteobacteria, but showed positive correlations with Eurotiales and Bacilli. This study has demonstrated that abundant fungal taxa are the predominant biological agents responsible for tobacco mildew, while bacteria may indirectly contribute to this process through the production and degradation of metabolites. KEY POINTS: • Fungi exhibited greater sensitivity to mildew of tobacco leaf compared to bacteria • Rare fungal taxa underwent significant damage during the mildew process • Mildew may damage the defense system of the tobacco leaf microecosystem.


Assuntos
Bacillus , Micobioma , China , Bactérias/genética , Fungos/genética , Nicotiana
3.
Nano Lett ; 22(15): 6075-6082, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35895892

RESUMO

Molecular spins on surfaces potentially used in quantum information processing and data storage require long spin excitation lifetimes. Normally, coupling of the molecular spin with the conduction electrons of metallic surfaces causes fast relaxation of spin excitations. However, the presence of superconducting pairing effects in the substrate can protect the excited spin from decaying. In this work, we show that a proximity-induced superconducting gold film can sustain spin excitations of a FeTPP-Cl molecule for more than 80 ns. This long value was determined by studying inelastic spin excitations of the S = 5/2 multiplet of FeTPP-Cl on Au films over V(100) using scanning tunneling spectroscopy. The spin lifetime decreases with increasing film thickness, along with the decrease of the effective superconducting gap. Our results elucidate the use of proximitized gold electrodes for addressing quantum spins on surfaces, envisioning new routes for tuning the value of their spin lifetime.


Assuntos
Ouro , Supercondutividade , Fenômenos Físicos , Análise Espectral
4.
Angew Chem Int Ed Engl ; 62(41): e202307884, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37604782

RESUMO

Triangulenes are a class of open-shell triangular graphene flakes with total spin increasing with their size. In the last years, on-surface-synthesis strategies have permitted fabricating and engineering triangulenes of various sizes and structures with atomic precision. However, direct proof of the increasing total spin with their size remains elusive. In this work, we report the combined in-solution and on-surface synthesis of a large nitrogen-doped triangulene (aza-[5]-triangulene) on a Au(111) surface, and the detection of its high-spin ground state. Bond-resolved scanning tunneling microscopy images uncovered radical states distributed along the zigzag edges, which were detected as weak zero-bias resonances in scanning tunneling spectra. These spectral features reveal the partial Kondo screening of a high-spin state. Through a combination of several simulation tools, we find that the observed distribution of radical states is explained by a quintet ground state (S=2), instead of the quartet state (S=3/2) expected for the neutral species. This confirms that electron transfer to the metal substrate raises the spin of the ground state. We further provide a qualitative description of the change of (anti)aromaticity introduced by N-substitution, and its role in the charge stabilization on a surface, resulting in an S=2 aza-triangulene on Au(111).

5.
Appl Opt ; 61(1): 294-301, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35200831

RESUMO

A scheme to generate a frequency 32-tupling millimeter wave (mm-wave) is proposed, enabled by two dual-parallel polarization modulators (DP-PolMs) in cascade. By properly controlling the amplitude and the phase shift of the radio-frequency (RF) driving signal applied to two DP-PolMs, the main optical components at the output of the DP-PolM are ±16th order optical sidebands and the central carrier. After the central carrier is canceled by the polarization multiplexing structure, the ±16th order optical sidebands are beaten in the photodetector; then the frequency 32-tupling mm-wave can be achieved. The optical sideband suppression ratio (OSSR) and the radio-frequency spurious suppression ratio (RFSSR) of the generated signal are 52 and 47 dB in simulation, which are consistent with the theoretical analysis values 53.7 and 47.7 dB. The influence on the OSSR and RFSSR of the generated signal by the key parameters of devices deviating from the theoretical analysis value i are investigated.

6.
Int J Mol Sci ; 23(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35563391

RESUMO

Plant architecture is dynamic as plants develop. Although many genes associated with specific plant architecture components have been identified in rice, genes related to underlying dynamic changes in plant architecture remain largely unknown. Here, we identified two highly similar recombinant inbred lines (RILs) with different plant architecture: RIL-Dynamic (D) and RIL-Compact (C). The dynamic plant architecture of RIL-D is characterized by 'loosetiller angle (tillering stage)-compact (heading stage)-loosecurved stem (maturing stage)' under natural long-day (NLD) conditions, and 'loosetiller angle (tillering and heading stages)-loosetiller angle and curved stem (maturing stage)' under natural short-day (NSD) conditions, while RIL-C exhibits a compact plant architecture both under NLD and NSD conditions throughout growth. The candidate locus was mapped to the chromosome 9 tail via the rice 8K chip assay and map-based cloning. Sequencing, complementary tests, and gene knockout tests demonstrated that Tiller Angle Control 1 (TAC1) is responsible for dynamic plant architecture in RIL-D. Moreover, TAC1 positively regulates loose plant architecture, and high TAC1 expression cannot influence the expression of tested tiller-angle-related genes. Our results reveal that TAC1 is necessary for the dynamic changes in plant architecture, which can guide improvements in plant architecture during the modern super rice breeding.


Assuntos
Oryza , Oryza/metabolismo , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
7.
Phys Rev Lett ; 126(7): 076802, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33666492

RESUMO

Yu-Shiba-Rusinov (YSR) bound states appear when a magnetic atom interacts with a superconductor. Here, we report on spin-resolved spectroscopic studies of YSR states related with Fe atoms deposited on the surface of the topological superconductor FeTe_{0.55}Se_{0.45} using a spin-polarized scanning tunneling microscope. We clearly identify the spin signature of pairs of YSR bound states at finite energies within the superconducting gap having opposite spin polarization as theoretically predicted. In addition, we also observe zero-energy bound states for some of the adsorbed Fe atoms. In this case, a spin signature is found to be absent indicating the absence of Majorana bound states associated with Fe adatoms on FeTe_{0.55}Se_{0.45}.

8.
Arterioscler Thromb Vasc Biol ; 40(7): 1705-1721, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32268790

RESUMO

OBJECTIVE: A decrease in nitric oxide, leading to vascular smooth muscle cell proliferation, is a common pathological feature of vascular proliferative diseases. Nitric oxide synthesis by eNOS (endothelial nitric oxide synthase) is precisely regulated by protein kinases including AKT1. ENH (enigma homolog protein) is a scaffolding protein for multiple protein kinases, but whether it regulates eNOS activation and vascular remodeling remains unknown. Approach and Results: ENH was upregulated in injured mouse arteries and human atherosclerotic plaques and was associated with coronary artery disease. Neointima formation in carotid arteries, induced by ligation or wire injury, was greatly decreased in endothelium-specific ENH-knockout mice. Vascular ligation reduced AKT and eNOS phosphorylation and nitric oxide production in the endothelium of control but not ENH-knockout mice. ENH was found to interact with AKT1 and its phosphatase PHLPP2 (pleckstrin homology domain and leucine-rich repeat protein phosphatase 2). AKT and eNOS activation were prolonged in VEGF (vascular endothelial growth factor)-induced ENH- or PHLPP2-deficient endothelial cells. Inhibitors of either AKT or eNOS effectively restored ligation-induced neointima formation in ENH-knockout mice. Moreover, endothelium-specific PHLPP2-knockout mice displayed reduced ligation-induced neointima formation. Finally, PHLPP2 was increased in the endothelia of human atherosclerotic plaques and blood cells from patients with coronary artery disease. CONCLUSIONS: ENH forms a complex with AKT1 and its phosphatase PHLPP2 to negatively regulate AKT1 activation in the artery endothelium. AKT1 deactivation, a decrease in nitric oxide generation, and subsequent neointima formation induced by vascular injury are mediated by ENH and PHLPP2. ENH and PHLPP2 are thus new proatherosclerotic factors that could be therapeutically targeted.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Lesões das Artérias Carótidas/enzimologia , Artéria Carótida Primitiva/enzimologia , Proteínas dos Microfilamentos/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Remodelação Vascular , Proteínas Adaptadoras de Transdução de Sinal/deficiência , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Aterosclerose/enzimologia , Aterosclerose/patologia , Aterosclerose/fisiopatologia , Lesões das Artérias Carótidas/genética , Lesões das Artérias Carótidas/patologia , Lesões das Artérias Carótidas/fisiopatologia , Artéria Carótida Primitiva/patologia , Artéria Carótida Primitiva/fisiopatologia , Células Cultivadas , Doença da Artéria Coronariana/enzimologia , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/fisiopatologia , Modelos Animais de Doenças , Células Endoteliais da Veia Umbilical Humana/enzimologia , Humanos , Proteínas com Domínio LIM/genética , Proteínas com Domínio LIM/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas dos Microfilamentos/deficiência , Proteínas dos Microfilamentos/genética , Neointima , Óxido Nítrico/metabolismo , Fosfoproteínas Fosfatases/deficiência , Fosfoproteínas Fosfatases/genética , Fosforilação , Transdução de Sinais
9.
Plant Cell Rep ; 40(5): 835-850, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33730215

RESUMO

KEY MESSAGE: The R89 is essential for the kinase activity of OsMPK6 which negatively regulates cell death and defense response in rice. Mitogen-activated protein kinase cascade plays critical roles in various vital activities, including the plant immune response, but the mechanisms remain elusive. Here, we identified and characterized a rice lesion mimic mutant osmpk6 which displayed hypersensitive response-like lesions in company with cell death and hydrogen peroxide hyperaccumulation. Map-based cloning and complementation demonstrated that a G702A single-base substitution in the second exon of OsMPK6 led to the lesion mimic phenotype of the osmpk6 mutant. OsMPK6 encodes a cytoplasm and nucleus-targeted mitogen-activated protein kinase and is expressed in the various organs. Compared with wild type, the osmpk6 mutant exhibited high resistance to the bacterial pathogen Xanthomonas oryzae pv. oryzae (Xoo), likely due to the increased ROS production induced by flg22 and chitin and up-regulated expression of genes involved in pathogenesis, as well as activation of SA and JA signaling pathways after inoculation. By contrast, the OsMPK6-overexpression line (OE-1) was found to be susceptible to the bacterial pathogens, indicating that OsMPK6 negatively regulated Xoo resistance. Furthermore, the G702A single-base substitution caused a R89K mutation at both polypeptide substrate-binding site and active site of OsMPK6, and kinase activity assay revealed that the R89K mutation led to reduction of OsMPK6 activity, suggesting that the R89 is essential for the function of OsMPK6. Our findings provide insight into a vital role of the R89 of OsMPK6 in regulating cell death and defense response in rice.


Assuntos
Oryza/metabolismo , Oryza/microbiologia , Xanthomonas/patogenicidade , Quitina/genética , Quitina/metabolismo , Resistência à Doença/genética , Resistência à Doença/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Oryza/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
10.
Int J Med Sci ; 17(15): 2328-2337, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922198

RESUMO

Background: Dilated cardiomyopathy (DCM) is considered as the most common form of non-ischemic cardiomyopathy with a high mortality worldwide. Cytoskeleton protein Cypher plays an important role in maintaining cardiac function. Genetic studies in human and animal models revealed that Cypher is involved in the development of DCM. However, the underlying molecular mechanism is not fully understood. Accumulating evidences suggest that apoptosis in myocytes may contribute to DCM. Thus, the purpose of this study is to define whether lack of Cypher in cardiomyocytes can elevate apoptosis signaling and lead to DCM eventually. Methods and Results: Cypher-siRNA sufficiently inhibited Cypher expression in cardiomyocytes. TUNEL-positive cardiomyocytes were increased in both Cypher knockdown neonatal rat cardiomyocytes and Cypher knockout mice hearts, which were rare in the control group. Flow cytometry further confirmed that downregulation of Cypher significantly increased myocytes apoptosis in vitro. Cell counting kit-8 assay revealed that Cypher knockdown in H9c2 cells significantly reduced cell viability. Cypher knockdown was found to increase cleaved caspase-3 expression and suppress p21, ratio of bcl-2 to Bax. Cypher-deficiency induced apoptosis was linked to downregulation of Akt activation and elevated p-p38 MAPK accumulation. Pharmacological activation of Akt with SC79 attenuated apoptosis with enhanced phosphorylation of Akt and reduced p-p38 MAPK and Bax expression. Conclusions: Downregulation of Cypher participates in the promotion of cardiomyocytes apoptosis through inhibiting Akt dependent pathway and enhancing p38 MAPK phosphorylation. These findings may provide a new potential therapeutic strategy for the treatment of DCM.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/deficiência , Cardiomiopatia Dilatada/patologia , Proteínas com Domínio LIM/deficiência , Miócitos Cardíacos/patologia , Acetatos/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Benzopiranos/farmacologia , Cardiomiopatia Dilatada/genética , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Regulação para Baixo , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Proteínas com Domínio LIM/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Knockout , Miocárdio/citologia , Miocárdio/patologia , Fosforilação/efeitos dos fármacos , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt/agonistas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Angew Chem Int Ed Engl ; 59(40): 17413-17416, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32603012

RESUMO

The thermally induced cyclodehydrofluorization of iron tetrakis(pentafluorophenyl)porphyrin proceeded highly stereoselectively to give a prochiral product on a gold surface in an ultrahigh vacuum, whereas dehydrocyclization of the respective iron tetrakisphenylporphyrin did not show such selectivity. Stereoselectivity was predominantly observed for closely packed layers, which is an indication of intermolecular cooperativity and steric constraints induced by adjacent species. Density functional theory identified intermolecular packing constraints as the origin of such selectivity during the reaction. Scanning tunneling microscopy revealed the formation of an enantiomerically pure two-dimensional self-assembly as a conglomerate of mirror domains. On-surface two-dimensional topochemistry, as reported herein, may open new routes for stereoselective synthesis.

12.
J Cell Mol Med ; 23(10): 7054-7062, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31424159

RESUMO

Idiopathic dilated cardiomyopathy (IDCM), characterized by ventricular dilation and impaired systolic function, is a primary cardiomyopathy resulting in heart failure. During heart contraction, the Z-line is responsible for transmitting force between sarcomeres and is also a hot spot for muscle cell signalling. Mutations in Z-line proteins have been linked to cardiomyopathies in both humans and mice. Actinin-associated LIM protein (ALP) and enigma homolog protein (ENH), encoded by PDLIM3 and PDLIM5, are components of the muscle cytoskeleton and localize to the Z-line. A PDLIM3 or PDLIM5 deficiency in mice leads to dilated cardiomyopathy. Since PDLIM3 and PDLIM5 are candidate IDCM susceptibility genes, the current study aims to investigate whether polymorphisms within PDLIM3 and PDLIM5 could be correlated with IDCM. We designed a case-control study, and exons of the PDLIM3 and PDLIM5 were amplified by polymerase chain reactions in 111 IDCM patients and 137 healthy controls. We found that five synonymous polymorphisms had statistical distribution differences between IDCM patients and controls, including rs4861669, rs4862543, c.731 + 131 T > G, c.1789-3 C > T and rs7690296, according to genotype and allele distribution. Haplotype G-C-C-C and A-T-C-T (rs2306705, rs10866276, rs12644280 and rs4635850 synthesized) were regarded as risk factors for IDCM patients when compared with carriers of other haplotypes (all P < .05). Furthermore, IDCM patients with two novel polymorphisms (c.731 + 131 T > G and c.1789-3 C > T) had lower systolic blood pressure. In conclusion, these five synonymous polymorphisms might constitute a genetic background that increases the risk of the development of IDCM in the Chinese Han population.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Cardiomiopatia Dilatada/genética , Predisposição Genética para Doença , Proteínas com Domínio LIM/genética , Proteínas dos Microfilamentos/genética , Polimorfismo de Nucleotídeo Único/genética , Alelos , Pressão Sanguínea/genética , Cardiomiopatia Dilatada/fisiopatologia , Estudos de Casos e Controles , Etnicidade/genética , Feminino , Haplótipos/genética , Humanos , Desequilíbrio de Ligação/genética , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Sístole/genética
13.
Nano Lett ; 17(8): 4929-4933, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28727436

RESUMO

The quantum efficiency or the rate of conversion of incident photon to free electron in photosynthesis is known to be extremely high. It has long been thought that the origin of this efficiency are molecular vibrations leading to a very fast separation of electrons and holes within the involved molecules. However, molecular vibrations are commonly in the range above 100 meV, which is too high for excitations in an ambient environment. Here, we analyze experimental spectra of single organic molecules on metal surfaces at ∼4 K, which often exhibit a pronounced dip. We show that measurements on iron(II) [tetra-(pentafluorophenyl)]porphyrin resolve this single dip at 4 K into a series of step-shaped inelastic excitations at 0.4 K. Via extensive spectral maps under applied magnetic fields and corresponding theoretical analysis we find that the dip is due to ultralow-energy vibrations of the molecular frame, typically in the range below 20 meV. The result indicates that ultralow energy vibrations in organic molecules are much more common than currently thought and may be all-pervasive for molecules above a certain size.

14.
Nano Lett ; 15(10): 6464-8, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26348981

RESUMO

Doping graphene with boron has been difficult because of high reaction barriers. Here, we describe a low-energy reaction route derived from first-principles calculations and validated by experiments. We find that a boron atom on graphene on a ruthenium(0001) substrate can replace a carbon by pushing it through, with substrate attraction helping to reduce the barrier to only 0.1 eV, implying that the doping can take place at room temperature. High-quality graphene is grown on a Ru(0001) surface and exposed to B2H6. Scanning tunneling microscopy/spectroscopy and X-ray photoelectron spectroscopy confirmed that boron is indeed incorporated substitutionally without disturbing the graphene lattice.

16.
Theranostics ; 14(11): 4462-4480, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39113806

RESUMO

Rationale: Cardiomyocytes (CMs) undergo dramatic structural and functional changes in postnatal maturation; however, the regulatory mechanisms remain greatly unclear. Cypher/Z-band alternatively spliced PDZ-motif protein (ZASP) is an essential sarcomere component maintaining Z-disc stability. Deletion of mouse Cypher and mutation in human ZASP result in dilated cardiomyopathy (DCM). Whether Cypher/ZASP participates in CM maturation and thereby affects cardiac function has not been answered. Methods: Immunofluorescence, transmission electron microscopy, real-time quantitative PCR, and Western blot were utilized to identify the role of Cypher in CM maturation. Subsequently, RNA sequencing and bioinformatics analysis predicted serum response factor (SRF) as the key regulator. Rescue experiments were conducted using adenovirus or adeno-associated viruses encoding SRF, both in vitro and in vivo. The molecular mechanisms were elucidated through G-actin/F-actin fractionation, nuclear-cytoplasmic extraction, actin disassembly assays, and co-sedimentation assays. Results: Cypher deletion led to impaired sarcomere isoform switch and morphological abnormalities in mitochondria, transverse-tubules, and intercalated discs. RNA-sequencing analysis revealed significant dysregulation of crucial genes related to sarcomere assembly, mitochondrial metabolism, and electrophysiology in the absence of Cypher. Furthermore, SRF was predicted as key transcription factor mediating the transcriptional differences. Subsequent rescue experiments showed that SRF re-expression during the critical postnatal period effectively rectified CM maturation defects and notably improved cardiac function in Cypher-depleted mice. Mechanistically, Cypher deficiency resulted in the destabilization of F-actin and a notable increase in G-actin levels, thereby impeding the nuclear localisation of myocardin-related transcription factor A (MRTFA) and subsequently initiating SRF transcription. Conclusion: Cypher/ZASP plays a crucial role in CM maturation through actin-mediated MRTFA-SRF signalling. The linkage between CM maturation abnormalities and the late-onset of DCM is suggested, providing further insights into the pathogenesis of DCM and potential treatment strategies.


Assuntos
Actinas , Cardiomiopatia Dilatada , Miócitos Cardíacos , Fator de Resposta Sérica , Transdução de Sinais , Transativadores , Animais , Miócitos Cardíacos/metabolismo , Fator de Resposta Sérica/metabolismo , Fator de Resposta Sérica/genética , Camundongos , Actinas/metabolismo , Transativadores/metabolismo , Transativadores/genética , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/patologia , Sarcômeros/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Humanos , Camundongos Knockout
17.
Cardiovasc Res ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39028686

RESUMO

AIMS: Circular RNAs (circRNAs) are considered important regulators of biological processes, but their impact on atherosclerosis development, a key factor in coronary artery disease (CAD), has not been fully elucidated. We aimed to investigate their potential use in patients with CAD and the pathogenesis of atherosclerosis. METHODS AND RESULTS: Patients with stable angina (SA) or acute coronary syndrome (ACS) and controls were selected for transcriptomic screening and quantification of circRNAs in blood cells. We stained carotid plaque samples for circRNAs and performed gain- and loss-of-function studies in vitro. Western blots, protein interaction analysis, and molecular approaches were used to perform the mechanistic study. ApoE-/- mouse models were employed in functional studies with adeno-associated virus-mediated genetic intervention. We demonstrated elevated circARCN1 expression in peripheral blood mononuclear cells from patients with SA or ACS, especially in those with ACS. Furthermore, higher circARCN1 levels were associated with a higher risk of developing SA and ACS. We also observed elevated expression of circARCN1 in carotid artery plaques. Further analysis indicated that circARCN1 was mainly expressed in monocytes and macrophages, which was also confirmed in atherosclerotic plaques. Our in vitro studies provided evidence that circARCN1 affected the interaction between HuR and ubiquitin-specific peptidase 31 (USP31) mRNA, resulting in attenuated USP31-mediated NF-κB activation. Interestingly, macrophage accumulation and inflammation in atherosclerotic plaques were markedly decreased when circARCN1 was knocked down with adeno-associated virus in macrophages of ApoE-/- mice, while circARCN1 overexpression in the model exacerbated atherosclerotic lesions. CONCLUSIONS: Our findings provide solid evidence macrophagic-expressed circARCN1 plays a role in atherosclerosis development by regulating HuR-mediated USP31 mRNA stability and NF-κB activation, suggesting that circARCN1 may serve as a factor for atherosclerotic lesion formation.

18.
Transl Cancer Res ; 12(11): 3222, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38130303

RESUMO

[This retracts the article DOI: 10.21037/tcr.2020.04.26.].

19.
Nat Commun ; 14(1): 1018, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36823140

RESUMO

Stacking two-dimensional layered materials such as graphene and transitional metal dichalcogenides with nonzero interlayer twist angles has recently become attractive because of the emergence of novel physical properties. Stacking of one-dimensional nanomaterials offers the lateral stacking offset as an additional parameter for modulating the resulting material properties. Here, we report that the edge states of twisted bilayer zigzag graphene nanoribbons (TBZGNRs) can be tuned with both the twist angle and the stacking offset. Strong edge state variations in the stacking region are first revealed by density functional theory (DFT) calculations. We construct and characterize twisted bilayer zigzag graphene nanoribbon (TBZGNR) systems on a Au(111) surface using scanning tunneling microscopy. A detailed analysis of three prototypical orthogonal TBZGNR junctions exhibiting different stacking offsets by means of scanning tunneling spectroscopy reveals emergent near-zero-energy states. From a comparison with DFT calculations, we conclude that the emergent edge states originate from the formation of flat bands whose energy and spin degeneracy are highly tunable with the stacking offset. Our work highlights fundamental differences between 2D and 1D twistronics and spurs further investigation of twisted one-dimensional systems.

20.
Front Cardiovasc Med ; 9: 945142, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093152

RESUMO

The ATP consumption in heart is very intensive to support muscle contraction and relaxation. Mitochondrion is the power plant of the cell. Mitochondrial dysfunction has long been believed as the primary mechanism responsible for the inability of energy generation and utilization in heart failure. In addition, emerging evidence has demonstrated that mitochondrial dysfunction also contributes to calcium dysregulation, oxidative stress, proteotoxic insults and cardiomyocyte death. These elements interact with each other to form a vicious circle in failing heart. The role of mitochondrial dysfunction in the pathogenesis of heart failure has attracted increasing attention. The complex signaling of mitochondrial quality control provides multiple targets for maintaining mitochondrial function. Design of therapeutic strategies targeting mitochondrial dysfunction holds promise for the prevention and treatment of heart failure.

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