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1.
Cell Commun Signal ; 22(1): 345, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943195

RESUMO

BACKGROUND: The neonatal mammalian heart exhibits considerable regenerative potential following injury through cardiomyocyte proliferation, whereas mature cardiomyocytes withdraw from the cell cycle and lose regenerative capacities. Therefore, investigating the mechanisms underlying neonatal cardiomyocyte proliferation and regeneration is crucial for unlocking the regenerative potential of adult mammalian heart to repair damage and restore contractile function following myocardial injury. METHODS: The Tudor staphylococcal nuclease (Tudor-SN) transgenic (TG) or cardiomyocyte-specific knockout mice (Myh6-Tudor-SN -/-) were generated to investigate the role of Tudor-SN in cardiomyocyte proliferation and heart regeneration following apical resection (AR) surgery. Primary cardiomyocytes isolated from neonatal mice were used to assess the influence of Tudor-SN on cardiomyocyte proliferation in vitro. Affinity purification and mass spectrometry were employed to elucidate the underlying mechanism. H9c2 cells and mouse myocardia with either overexpression or knockout of Tudor-SN were utilized to assess its impact on the phosphorylation of Yes-associated protein (YAP), both in vitro and in vivo. RESULTS: We previously identified Tudor-SN as a cell cycle regulator that is highly expressed in neonatal mice myocardia but downregulated in adults. Our present study demonstrates that sustained expression of Tudor-SN promotes and prolongs the proliferation of neonatal cardiomyocytes, improves cardiac function, and enhances the ability to repair the left ventricular apex resection in neonatal mice. Consistently, cardiomyocyte-specific knockout of Tudor-SN impairs cardiac function and retards recovery after injury. Tudor-SN associates with YAP, which plays important roles in heart development and regeneration, inhibiting phosphorylation at Ser 127 and Ser 397 residues by preventing the association between Large Tumor Suppressor 1 (LATS1) and YAP, correspondingly maintaining stability and promoting nuclear translocation of YAP to enhance the proliferation-related genes transcription. CONCLUSION: Tudor-SN regulates the phosphorylation of YAP, consequently enhancing and prolonging neonatal cardiomyocyte proliferation under physiological conditions and promoting neonatal heart regeneration after injury.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Animais Recém-Nascidos , Proliferação de Células , Miócitos Cardíacos , Regeneração , Proteínas de Sinalização YAP , Animais , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Miócitos Cardíacos/citologia , Fosforilação , Proteínas de Sinalização YAP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Camundongos , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Coração/fisiologia , Camundongos Knockout , Ratos
2.
J Environ Manage ; 356: 120642, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503227

RESUMO

The polysilicate aluminum ferric (PSAF) was synthesized via copolymerization of polysilicic acid (PSi), AlCl3 and FeCl3 for treating oily wastewater from Daqing gas field. This study investigated the effects of key preparation factors such as the degree of PSi's preactivation and the ratio of (Fe + Al)/Si and Al/Fe on both polymerization and coagulation performance exhibited by PSAF. To determine the optimal timing for introducing Al3+ and Fe3+, zeta potential, viscosity and particle size were investigated. Additionally, infrared spectroscopy, X-ray powder diffraction, polarizing microscopy and scanning electron microscope analysis were employed to investigate the structure and morphology of PSAF. The results indicate that under conditions characterized by a SiO2 mass fraction of 2.5% and pH = 4.5, an optimal timing for introducing Al3+ and Fe3+ is at 100 min when PSi exhibits moderate polymerization along with sufficient stability. When considering molar ratios such as (Al + Fe)/Si being 6:4 and Al/Fe being 5:5, respectively, PSAF falls within a "stable zone" enabling storage period up to 32 days. Moreover, Jar test results demonstrate that at a dosage of 200 mg/L PSAF for oily wastewater treatment in gas fields could reach the maximum turbidity removal efficiency up to 99.5% while oil removal efficiency reach 88.6% without pH adjustment. The copolymerization facilitates the formation of larger PSAF aggregates with positive potential, thereby augmenting the coagulants' adsorption bridging and charge neutralization capabilities. As a result, PSAF has great potential as a practical coagulant for treating oil-containing wastewater in industrial settings.


Assuntos
Águas Residuárias , Purificação da Água , Alumínio/química , Dióxido de Silício , Polímeros , Ferro/química , Purificação da Água/métodos , Compostos Férricos/química
3.
J Integr Plant Biol ; 65(1): 45-63, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36165397

RESUMO

Integration of light signaling and diverse abiotic stress responses contribute to plant survival in a changing environment. Some reports have indicated that light signals contribute a plant's ability to deal with heat, cold, and stress. However, the molecular link between light signaling and the salt-response pathways remains unclear. We demonstrate here that increasing light intensity elevates the salt stress tolerance of plants. Depletion of HY5, a key component of light signaling, causes Arabidopsis thaliana to become salinity sensitive. Interestingly, the small heat shock protein (sHsp) family genes are upregulated in hy5-215 mutant plants, and HsfA2 is commonly involved in the regulation of these sHsps. We found that HY5 directly binds to the G-box motifs in the HsfA2 promoter, with the cooperation of HISTONE DEACETYLASE 9 (HDA9), to repress its expression. Furthermore, the accumulation of HDA9 and the interaction between HY5 and HDA9 are significantly enhanced by salt stress. On the contrary, high temperature triggers HY5 and HDA9 degradation, which leads to dissociation of HY5-HDA9 from the HsfA2 promoter, thereby reducing salt tolerance. Under salt and heat stress conditions, fine tuning of protein accumulation and an interaction between HY5 and HDA9 regulate HsfA2 expression. This implies that HY5, HDA9, and HsfA2 play important roles in the integration of light signaling with salt stress and heat shock response.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Plantas/metabolismo , Estresse Salino/genética , Histona Desacetilases/metabolismo , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo
4.
Int J Mol Sci ; 20(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683506

RESUMO

Benzofuran (BF), benzothiophene (BT), indole (IN), dibenzofuran (DBF), dibenzothiophene (DBT), and carbazole (CA) are typical heterocyclic aromatic compounds (NSO-HETs), which can coexist with polycyclic aromatic hydrocarbons (PAHs) in combustion and pyrolysis conditions. In this work, quantum chemical calculations were carried out to investigate the formation of DBF, DBT, and CA from the reactions of BF, BT, and IN with a cyclopentadienyl radical (CPDyl) by using the hybrid density functional theory (DFT) at the MPWB1K/6-311+G(3df,2p)//MPWB1K/6-31+G(d,p) level. The rate constants of crucial elementary steps were deduced over 600-1200 K, using canonical variational transition state theory with a small-curvature tunneling contribution (CVT/SCT). This paper showed that the production of DBF, DBT, and CA from the reactions of BF, BT, and IN with CPDyl involved six elementary steps: the addition reaction, ring closure, the first H shift, C-C cleavage, the second H shift, and elimination of CH3 or H. The cleavage of the C-C bond was regarded as the rate-determining step for each pathway due to the extremely high barrier. The 1-methyl substituted products were more easily formed than the 4-methyl substituted products. The main products were DBF and 1-methyl-DBF, DBT and 1-methyl-DBT, and CA and 1-methyl-CA for reactions of BF, BT, and IN with CPDyl, respectively. The ranking of DBF, DBT, and CA formation potential was as follows: DBT and methyl-DBT formation > DBF and methyl-DBF formation > CA, and methyl-CA formation. Comparison with the reaction of naphthalene with CPDyl indicated that the reactions of CPDyl attacking a benzene ring and a furan/thiophene/pyrrole ring could be inferred to be comparable under high temperature conditions.


Assuntos
Benzofuranos/química , Ciclopentanos/química , Gases/química , Indóis/química , Hidrocarbonetos Policíclicos Aromáticos/química , Tiofenos/química , Benzofuranos/síntese química , Carbazóis/síntese química , Carbazóis/química , Radicais Livres/química , Cinética , Modelos Químicos , Modelos Moleculares , Estrutura Molecular , Hidrocarbonetos Policíclicos Aromáticos/síntese química , Tiofenos/síntese química
5.
J Virol Methods ; 320: 114788, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37517457

RESUMO

Sheeppox virus (SPPV), goatpox virus (GTPV) and lumpy skin disease virus (LSDV) belong to the genus Capripoxvirus (CaPV), and are important pathogens of sheep, goat and cattle, respectively. Rapid and reliable detection of CaPV is critical to prevent its spread and promote its eradication. This study aimed to develop the recombinase polymerase amplification (RPA) assays combined with real-time fluorescence (real-time RPA) and naked-eye visible lateral flow strip (LFS RPA) for rapid detection of CaPV. Both developed RPA assays worked well at 39 °C within 20 min. They were highly specific for the detection of GTPV, SPPV and LSDV, while no cross-reactivity was observed for other non-targeted pathogens and genomic DNA of goat, sheep and cattle. The limit of detection for real-time RPA and LFS RPA were 1.0 × 102 and 1.0 × 101 copies per reaction, respectively. In the artificially contaminated samples with GTPV, the detection results of RPA assays were consistent with those of real-time PCR. For 15 clinical samples, LSDV was detected by real-time RPA, LFS RPA and real-time PCR in 13, 15 and 15 samples, respectively. The developed RPA assays were specific, sensitive, and user-friendly for the rapid detection of CaPV, and could be a better alternative method applied in low-resources settings.


Assuntos
Capripoxvirus , Técnicas de Amplificação de Ácido Nucleico , Infecções por Poxviridae , Capripoxvirus/genética , Capripoxvirus/isolamento & purificação , Recombinases , Técnicas de Amplificação de Ácido Nucleico/métodos , Proteínas Virais/genética , Infecções por Poxviridae/veterinária , Infecções por Poxviridae/virologia , Animais , Bovinos , Ovinos , Cabras , Sensibilidade e Especificidade
6.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 27(2): 365-8, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20481320

RESUMO

In this study, we successfully expanded a full length gene encoding the monooxygenase eytochrome P450 2C9 gene from human liver of Chinese Han by RT-PCR. Our findings indicated that except G-->T mutation at the 190th nucleotide site, the other nucleotide sequences are completely consistent with CYP2C9 (NM017460) in GenBank. The SDS-PAGE and Western-Blot analysis showed that the CYP 2C9 gene was successfully expressed in the host cell E. coli BL21 (DE3). Our current study lays the foundation for the evaluation of pre-clinical drug metabolism and safety in the future.


Assuntos
Hidrocarboneto de Aril Hidroxilases/biossíntese , Hidrocarboneto de Aril Hidroxilases/genética , Vetores Genéticos/genética , Mutação Puntual , China/etnologia , Clonagem Molecular , Citocromo P-450 CYP2C9 , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Polimorfismo Genético , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 5014-5017, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30441467

RESUMO

In this new research, we expand on our previous system for vocal fatigue detection by adding five new features in the classifier. We also perform further testing on 37 test subjects. The goals were: 1) to classify subjects performing normal versus simulated pressed vocal gestures; 2) to distinguish vocally healthy from vocally fatigued subjects as determined by VFI score on factor 1; and 3) to determine the validity of the labels vis-a-vis the choice of this same VFI-factor-1 boundary. As the results demonstrated, the choice of classifier and the new features were quite appropriate, while there is margin for better choices of the VFI-factor-1 boundary.


Assuntos
Distúrbios da Voz , Fadiga , Humanos
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