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1.
Proc Natl Acad Sci U S A ; 121(31): e2407472121, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39047038

RESUMO

The integrated stress response (ISR), a pivotal protein homeostasis network, plays a critical role in the formation of long-term memory (LTM). The precise mechanism by which the ISR controls LTM is not well understood. Here, we report insights into how the ISR modulates the mnemonic process by using targeted deletion of the activating transcription factor 4 (ATF4), a key downstream effector of the ISR, in various neuronal and non-neuronal cell types. We found that the removal of ATF4 from forebrain excitatory neurons (but not from inhibitory neurons, cholinergic neurons, or astrocytes) enhances LTM formation. Furthermore, the deletion of ATF4 in excitatory neurons lowers the threshold for the induction of long-term potentiation, a cellular model for LTM. Transcriptomic and proteomic analyses revealed that ATF4 deletion in excitatory neurons leads to upregulation of components of oxidative phosphorylation pathways, which are critical for ATP production. Thus, we conclude that ATF4 functions as a memory repressor selectively within excitatory neurons.


Assuntos
Fator 4 Ativador da Transcrição , Memória de Longo Prazo , Neurônios , Animais , Camundongos , Fator 4 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/genética , Astrócitos/metabolismo , Potenciação de Longa Duração , Memória de Longo Prazo/fisiologia , Camundongos Knockout , Neurônios/metabolismo , Prosencéfalo/metabolismo , Masculino
2.
Inorg Chem ; 63(29): 13253-13264, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38984385

RESUMO

Efficient CO oxidation at ambient or low temperatures is essential for environmental purification and selective CO oxidation in H2, yet achieving this remains a challenge with current methodologies. In this research, we extensively evaluated the catalytic performance of phosphotungstic acid (PTA)-supported 11 M1/PTA single-atom catalysts (SACs) using density functional theory calculations across both gas phase and 12 common solvents. The Rh1/PTA, Pd1/PTA, and Pt1/PTA systems exhibit moderate CO adsorption energies, facilitating the feasibility of oxygen vacancy formation. Remarkably, the Pd1/PTA and Pt1/PTA catalysts exhibited negligible energy barriers and demonstrated exceptionally high catalytic rates, with values reaching up to (1 × 1010)11, markedly exceeding the threshold for room temperature reactions, set at 6.55 × 108. This phenomenon is attributed to a transition from the high-energy barrier processes of oxygen dissociation in O2 and N-O bond dissociation in N2O to the more efficient dissociation of H2O2. Orbital analysis and charge variations at metal sites throughout the reaction process provide deeper insights into the role of the three metal catalytic sites in CO activation. Our findings not only reveal key aspects of SACs in facilitating CO oxidation at low temperatures but also provide valuable insights for future catalytic reaction mechanism studies and environmental applications.

3.
BMC Psychiatry ; 24(1): 387, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783266

RESUMO

BACKGROUND: Low concentrations of S100B have neurotrophic effects and can promote nerve growth and repair, which plays an essential role in the pathophysiological and histopathological alterations of major depressive disorder (MDD) during disease development. Studies have shown that plasma S100B levels are altered in patients with MDD. In this study, we investigated whether the plasma S100B levels in MDD differ between genders. METHODS: We studied 235 healthy controls (HCs) (90 males and 145 females) and 185 MDD patients (65 males and 120 females). Plasma S100B levels were detected via multifactor assay. The Mahalanobis distance method was used to detect the outliers of plasma S100B levels in the HC and MDD groups. The Kolmogorov-Smirnov test was used to test the normality of six groups of S100B samples. The Mann-Whitney test and Scheirer-Ray-Hare test were used for the comparison of S100B between diagnoses and genders, and the presence of a relationship between plasma S100B levels and demographic details or clinical traits was assessed using Spearman correlation analysis. RESULTS: All individuals in the HC group had plasma S100B levels that were significantly greater than those in the MDD group. In the MDD group, males presented significantly higher plasma S100B levels than females. In the male group, the plasma S100B levels in the HC group were significantly higher than those in the MDD group, while in the female group, no significant difference was found between the HC and MDD groups. In the male MDD subgroup, there was a positive correlation between plasma S100B levels and years of education. In the female MDD subgroup, there were negative correlations between plasma S100B levels and age and suicidal ideation. CONCLUSIONS: In summary, plasma S100B levels vary with gender and are decreased in MDD patients, which may be related to pathological alterations in glial cells.


Assuntos
Transtorno Depressivo Maior , Subunidade beta da Proteína Ligante de Cálcio S100 , Humanos , Transtorno Depressivo Maior/sangue , Masculino , Feminino , Subunidade beta da Proteína Ligante de Cálcio S100/sangue , Adulto , Fatores Sexuais , Pessoa de Meia-Idade , Caracteres Sexuais , Biomarcadores/sangue , Estudos de Casos e Controles
4.
J Nanobiotechnology ; 22(1): 518, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39210464

RESUMO

Deoxyribonucleotide (DNA) is uniquely programmable and biocompatible, and exhibits unique appeal as a biomaterial as it can be precisely designed and programmed to construct arbitrary shapes. DNA hydrogels are polymer networks comprising cross-linked DNA strands. As DNA hydrogels present programmability, biocompatibility, and stimulus responsiveness, they are extensively explored in the field of biomedicine. In this study, we provide an overview of recent advancements in DNA hydrogel technology. We outline the different design philosophies and methods of DNA hydrogel preparation, discuss its special physicochemical characteristics, and highlight the various uses of DNA hydrogels in biomedical domains, such as drug delivery, biosensing, tissue engineering, and cell culture. Finally, we discuss the current difficulties facing DNA hydrogels and their potential future development.


Assuntos
Materiais Biocompatíveis , DNA , Hidrogéis , Engenharia Tecidual , Hidrogéis/química , DNA/química , Humanos , Engenharia Tecidual/métodos , Materiais Biocompatíveis/química , Animais , Sistemas de Liberação de Medicamentos/métodos , Engenharia Biomédica/métodos , Técnicas Biossensoriais/métodos , Técnicas de Cultura de Células/métodos
5.
Nano Lett ; 23(4): 1280-1288, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36719250

RESUMO

Large-scale screening of molecules in organisms requires high-throughput and cost-effective evaluating tools during preclinical development. Here, a novel in vivo screening strategy combining hierarchically structured biohybrid triboelectric nanogenerators (HB-TENGs) arrays with computational bioinformatics analysis for high-throughput pharmacological evaluation using Caenorhabditis elegans is described. Unlike the traditional methods for behavioral monitoring of the animals, which are laborious and costly, HB-TENGs with micropillars are designed to efficiently convert animals' behaviors into friction deformation and result in a contact-separation motion between two triboelectric layers to generate electrical outputs. The triboelectric signals are recorded and extracted to various bioinformation for each screened compound. Moreover, the information-rich electrical readouts are successfully demonstrated to be sufficient to predict a drug's identity by multiple-Gaussian-kernels-based machine learning methods. This proposed strategy can be readily applied to various fields and is especially useful in in vivo explorations to accelerate the identification of novel therapeutics.


Assuntos
Algoritmos , Caenorhabditis elegans , Animais , Eletricidade , Movimento (Física)
6.
Int J Mol Sci ; 25(10)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38791522

RESUMO

The role of lncRNA and circRNA in wheat grain development is still unclear. The objectives of this study were to characterize the lncRNA and circRNA in the wheat grain development and to construct the interaction network among lncRNA, circRNA, and their target miRNA to propose a lncRNA-circRNA-miRNA module related to wheat grain development. Full transcriptome sequencing on two wheat varieties (Annong 0942 and Anke 2005) with significant differences in 1000-grain weight at 10 d (days after pollination), 20 d, and 30 d of grain development were conducted. We detected 650, 736, and 609 differentially expressed lncRNA genes, and 769, 1054, and 1062 differentially expressed circRNA genes in the grains of 10 days, 20 days and 30 days after pollination between Annong 0942 and Anke 2005, respectively. An analysis of the lncRNA-miRNA and circRNA-miRNA targeting networks reveals that circRNAs exhibit a more complex and extensive interaction network in the development of cereal grains and the formation of grain shape. Central to these interactions are tae-miR1177, tae-miR1128, and tae-miR1130b-3p. In contrast, lncRNA genes only form a singular network centered around tae-miR1133 and tae-miR5175-5p when comparing between varieties. Further analysis is conducted on the underlying genes of all target miRNAs, we identified TaNF-YB1 targeted by tae-miR1122a and TaTGW-7B targeted by miR1130a as two pivotal regulatory genes in the development of wheat grains. The quantitative real-time PCR (qRT-PCR) and dual-luciferase reporter assays confirmed the target regulatory relationships between miR1130a-TaTGW-7B and miR1122a-TaNF-YB1. We propose a network of circRNA and miRNA-mediated gene regulation in the development of wheat grains.


Assuntos
Grão Comestível , Regulação da Expressão Gênica de Plantas , MicroRNAs , RNA Circular , RNA Longo não Codificante , Triticum , Triticum/genética , Triticum/crescimento & desenvolvimento , RNA Longo não Codificante/genética , RNA Circular/genética , RNA Circular/metabolismo , MicroRNAs/genética , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Redes Reguladoras de Genes , RNA de Plantas/genética , Perfilação da Expressão Gênica
7.
Phys Chem Chem Phys ; 25(17): 12352-12362, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37089118

RESUMO

We have investigated the surface structure and relative stability of ZnV2O6(001) using a thermodynamic technique based on density functional theory (DFT). We built Zn-V-O surface phase diagrams of various surface terminations using the obtained surface Gibbs free energy. In this study, we selected nine different surface terminations along the (001) crystal plane to elucidate that the E, G, H, and I terminations (as shown in Table 1) are the most stable configurations. We found that although their stability varies widely, the four terminations on the ZnV2O6(001) surface can be stabilized under specific thermodynamic equilibrium circumstances. Furthermore, we calculated the surface electronic structures of the four surface terminations and found that there are surface states conducive to visible light absorption at the G, H, and I terminations. The different termination structures are significant in improving the range and intensity of light absorption of ZnV2O6 in specific regions. The fact that the work functions fluctuate significantly for different surface terminations suggests that the work function of ZnV2O6 can be changed to increase photocatalytic activity by achieving thermodynamically favored surface terminations under appropriate conditions. The obtained surface phase diagram will further lay a foundation for the study of the ZnV2O6 surface. These results may help to explore the inherent properties of the ZnV2O6 surface and provide useful strategies for future experimental research on ZnV2O6-based photocatalysts.

8.
Int J Mol Sci ; 24(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37047150

RESUMO

The regulatory role of non-CpG methylation in mammals has been important in whole-genome bisulfite sequencing. It has also been suggested that non-CpG methylation regulates gene expression to affect the development and health of mammals. However, the dynamic regulatory mechanisms of genome-wide, non-CpG methylation during testicular development still require intensive study. In this study, we analyzed the dataset from the whole-genome bisulfite sequencing (WGBS) and the RNA-seq of precocious porcine testicular tissues across two developmental stages (1 and 75 days old) in order to explore the regulatory roles of non-CpG methylation. Our results showed that genes regulated by non-CpG methylation affect the development of testes in multiple pathways. Furthermore, several hub genes that are regulated by non-CpG methylation during testicular development-such as VEGFA, PECAM1, and FZD7-were also identified. We also found that the relative expression of FZD7 was downregulated by the zebularine-induced demethylation of the first exon of FZD7. This regulatory relationship was consistent with the results of the WGBS and RNA-seq analysis. The immature porcine Sertoli cells were transfected with RNAi to mimic the expression patterns of FZD7 during testicular development. The results of the simulation test showed that cell proliferation was significantly impeded and that cell cycle arrest at the G2 phase was caused by the siRNA-induced FZD7 inhibition. We also found that the percentage of early apoptotic Sertoli cells was decreased by transfecting them with the RNAi for FZD7. This indicates that FZD7 is an important factor in linking the proliferation and apoptosis of Sertoli cells. We further demonstrated that Sertoli cells that were treated with the medium collected from apoptotic cells could stimulate proliferation. These findings will contribute to the exploration of the regulatory mechanisms of non-CpG methylation in testicular development and of the relationship between the proliferation and apoptosis of normal somatic cells.


Assuntos
Metilação de DNA , Sulfitos , Animais , Masculino , Proliferação de Células/genética , Ilhas de CpG , Mamíferos , Suínos , Fatores de Troca do Nucleotídeo Guanina
9.
Int J Mol Sci ; 24(19)2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37833923

RESUMO

RNA N6-methyladenosine (m6A) modification is one of the principal post-transcriptional modifications and plays a dynamic role in testicular development and spermatogenesis. However, the role of m6A in porcine testis is understudied. Here, we performed a comprehensive analysis of the m6A transcriptome-wide profile in Shaziling pig testes at birth, puberty, and maturity. We analyzed the total transcriptome m6A profile and found that the m6A patterns were highly distinct in terms of the modification of the transcriptomes during porcine testis development. We found that key m6A methylated genes (AURKC, OVOL, SOX8, ACVR2A, and SPATA46) were highly enriched during spermatogenesis and identified in spermatogenesis-related KEGG pathways, including Wnt, cAMP, mTOR, AMPK, PI3K-Akt, and spliceosome. Our findings indicated that m6A methylations are involved in the complex yet well-organized post-transcriptional regulation of porcine testicular development and spermatogenesis. We found that the m6A eraser ALKBH5 negatively regulated the proliferation of immature porcine Sertoli cells. Furthermore, we proposed a novel mechanism of m6A modification during testicular development: ALKBH5 regulated the RNA methylation level and gene expression of SOX9 mRNA. In addition to serving as a potential target for improving boar reproduction, our findings contributed to the further understanding of the regulation of m6A modifications in male reproduction.


Assuntos
Epigenoma , Transcriptoma , Suínos , Masculino , Animais , Fosfatidilinositol 3-Quinases/metabolismo , Maturidade Sexual , Testículo/metabolismo , RNA/metabolismo
10.
BMC Nurs ; 22(1): 387, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853431

RESUMO

BACKGROUND: Workplace violence is a worldwide concern, and particularly affects nursing students. It has a seriously negative impact on nursing students' clinical learning experience and their physical and mental health. This study explored whether there are differences in psychological responses and coping styles among different gender nursing students after exposure to workplace violence, and investigated the causes for these differences. METHODS: We enrolled 22 nursing undergraduates from Guangzhou Medical University and Zunyi Medical University, China. Phenomenological qualitative research and online semi-structured interviews were conducted. The data were analyzed by the Colaizzi seven-step content analysis method. RESULTS: Two categories were collated: psychological experience and coping styles. Three themes of the former were extracted: negative emotional experience, low level of professional identity, and negative effect on self-efficacy. Two themes of the latter: responses to violence and adjustment after violence. In addition, fourteen subthemes were extracted. CONCLUSIONS: Different gender nursing students have different psychological experience and coping styles in the face of workplace violence. The causes of the differences are likely related to sociocultural factors and psychological gender status.

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