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1.
Small ; : e2404199, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949393

RESUMO

The performance of perovskite solar cells has been continuously improving. However, humidity stability has become a key problem that hinders its promotion in the process of commercialization. A buffer layer deposited by atomic layer deposition is a very helpful method to solve this problem. In this work, MgO film is deposited between Spiro-OMeTAD and electrode by low-temperature atomic layer deposition at 80 °C, which resists the erosion of water vapor, inhibits the migration of electrode metal ions and the decomposition products of perovskite, then finally improves the stability of the device. At the same time, the MgO buffer layer can passivate the defects of porous Spiro, thus enhancing carrier transport efficiency and device performance. The Cs0.05(FAPbI3)0.85(MAPbBr3)0.15 perovskite device with a MgO buffer layer has displayed PCE of 22.74%, also with a high Voc of 1.223 V which is an excellent performance in devices with same perovskite component. Moreover, the device with a MgO buffer layer can maintain 80% of the initial efficiency after 7200 h of storage at 35% relative humidity under room temperature. This is a major achievement for humidity stability in the world, providing more ideas for further improving the stability of perovskite devices.

2.
Int J Mol Sci ; 25(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38892101

RESUMO

The central dogma treats the ribosome as a molecular machine that reads one mRNA codon at a time as it adds each amino acid to its growing peptide chain. However, this and previous studies suggest that ribosomes actually perceive pairs of adjacent codons as they take three-nucleotide steps along the mRNA. We examined GNN codons, which we find are surprisingly overrepresented in eukaryote protein-coding open reading frames (ORFs), especially immediately after NNU codons. Ribosome profiling experiments in yeast revealed that ribosomes with NNU at their aminoacyl (A) site have particularly elevated densities when NNU is immediately followed (3') by a GNN codon, indicating slower mRNA threading of the NNU codon from the ribosome's A to peptidyl (P) sites. Moreover, if the assessment was limited to ribosomes that have only recently arrived at the next codon, by examining 21-nucleotide ribosome footprints (21-nt RFPs), elevated densities were observed for multiple codon classes when followed by GNN. This striking translation slowdown at adjacent 5'-NNN GNN codon pairs is likely mediated, in part, by the ribosome's CAR surface, which acts as an extension of the A-site tRNA anticodon during ribosome translocation and interacts through hydrogen bonding and pi stacking with the GNN codon. The functional consequences of 5'-NNN GNN codon adjacency are expected to influence the evolution of protein coding sequences.


Assuntos
Códon , Fases de Leitura Aberta , Biossíntese de Proteínas , RNA Mensageiro , Ribossomos , Códon/genética , Ribossomos/metabolismo , Ribossomos/genética , Fases de Leitura Aberta/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Anticódon/genética
3.
Dev Comp Immunol ; 156: 105159, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38492902

RESUMO

Stress-induced immunosuppression (SIIS) is one of the common problems in intensive poultry production, which brings enormous economic losses to the poultry industry. Accumulating evidence has shown that microRNAs (miRNAs) were important regulators of gene expression in the immune system. However, the miRNA-mediated molecular mechanisms underlying SIIS in chickens are still poorly understood. This study aimed to investigate the biological functions and regulatory mechanism of miRNAs in chicken SIIS. A stress-induced immunosuppression model was successfully established via daily injection of dexamethasone and analyzed miRNA expression in spleen. Seventy-four differentially expressed miRNAs (DEMs) was identified, and 229 target genes of the DEMs were predicted. Functional enrichment analysis the target genes revealed pathways related to immunity, such as MAPK signaling pathway and FoxO signaling pathway. The candidate miRNA, gga-miR-146a-5p, was found to be significantly downregulated in the Dex-induced chicken spleen, and we found that Dex stimulation significantly inhibited the expression of gga-miR-146a-5p in Chicken macrophages (HD11). Flow cytometry, 5-ethynyl-2'-deoxyuridine (EdU), cell counting kit-8 (CCK-8) and other assays indicated that gga-miR-146a-5p can promote the proliferation and inhibit apoptosis of HD11 cells. A dual-luciferase reporter assay suggested that the Interleukin 1 receptor associated kinase 2 (IRAK2) gene, which encoded a transcriptional factor, was a direct target of gga-miR-146a-5p, gga-miR-146a-5p suppressed the post-transcriptional activity of IRAK2. These findings not only improve our understanding of the specific functions of miRNAs in avian stress but also provide potential targets for genetic improvement of stress resistance in poultry.


Assuntos
Galinhas , Dexametasona , Macrófagos , MicroRNAs , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Galinhas/imunologia , Galinhas/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Dexametasona/farmacologia , Apoptose , Tolerância Imunológica , Regulação da Expressão Gênica , Terapia de Imunossupressão , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Baço/imunologia , Baço/metabolismo , Transdução de Sinais , Estresse Fisiológico/imunologia , Linhagem Celular , Quinases Associadas a Receptores de Interleucina-1/genética , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Proliferação de Células
4.
Neuropharmacology ; 246: 109834, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38181970

RESUMO

Protein L-isoaspartyl methyltransferase (PIMT/PCMT1) could repair l-isoaspartate (L-isoAsp) residues formed by deamidation of asparaginyl (Asn) residues or isomerization of aspartyl (Asp) residues in peptides and proteins during aging. Aside from abnormal accumulation of L-isoAsp, PIMT knockout (KO) mice mirrors some neuropathological hallmarks such as anxiety-like behaviors, impaired spatial memory and aberrant synaptic plasticity in the hippocampus of neurodegenerative diseases (NDs), including Alzheimer's disease (AD) and related dementias, and Parkinson's disease (PD). While some reports indicate the neuroprotective effect of madecassoside (MA) as a triterpenoid saponin component of Centella asiatica, its role against NDs-related anxiety and cognitive impairment remains unclear. Therefore, we investigated the effect of MA against anxiety-related behaviors in PIMT deficiency-induced mouse model of NDs. Results obtained from the elevated plus maze (EPM) test revealed that MA treatment alleviated anxiety-like behaviors in PIMT knockout mice. Furthermore, Real-time PCR, electroencephalogram (EEG) recordings, transmission electron microscopy analysis and ELISA were carried out to evaluate the expression of clock genes, sleep and synaptic function, respectively. The PIMT knockout mice were characterized by abnormal clock patterns, sleep disturbance and synaptic dysfunction, which could be improved by MA administration. Collectively, these findings suggest that MA exhibits neuroprotective effects associated with improved circadian rhythms sleep-wake cycle and synaptic plasticity in PIMT deficient mice, which could be translated to ameliorate anxiety-related symptoms and cognitive impairments in NDs.


Assuntos
Centella , Triterpenos , Camundongos , Animais , Proteína D-Aspartato-L-Isoaspartato Metiltransferase/química , Proteína D-Aspartato-L-Isoaspartato Metiltransferase/genética , Proteína D-Aspartato-L-Isoaspartato Metiltransferase/metabolismo , Centella/metabolismo , Ácido Isoaspártico/metabolismo , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Camundongos Knockout
5.
Neurochem Int ; 170: 105606, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37657764

RESUMO

Synaptic dysfunction is a typical pathophysiologic change in neurodegenerative diseases (NDs) such as Alzheimer's disease (AD), Parkinson's disease (PD), Hintington's disease (HD) and amyotrophic lateral sclerosis (ALS), which involves protein post-translational modifications (PTMs) including L-isoaspartate (L-isoAsp) formed by isomerization of aspartate or deamidation of asparagine. The formation of L-isoAsp could be repaired by protein L-isoaspartyl methyltransferase (PIMT). Some synaptic proteins have been identified as PIMT potential substrates and play an essential role in ensuring synaptic function. In this review, we discuss the role of certain synaptic proteins as PIMT substrates in neurodegenerative disease, thus providing therapeutic synapse-centered targets for the treatment of NDs.


Assuntos
Doenças Neurodegenerativas , Proteína D-Aspartato-L-Isoaspartato Metiltransferase , Humanos , Proteína D-Aspartato-L-Isoaspartato Metiltransferase/metabolismo , Doenças Neurodegenerativas/metabolismo , Proteínas/metabolismo , Ácido Isoaspártico/metabolismo , Ácido Aspártico/metabolismo
6.
J Histochem Cytochem ; 65(9): 543-558, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28745544

RESUMO

Euptox A (9-oxo-10, 11-dehydroageraphorone), the main toxin isolated from Eupatorium adenophorum, is known to induce immunotoxicity in animals. However, the precise mechanism underlying the effects of Euptox A on splenocytes is unclear. Here, we aimed to investigate the molecular mechanisms underlying the effect of Euptox A in mouse spleens after its intragastric administration and found that Euptox A exhibits proautophagic effects in splenocytes. Euptox A markedly arrested the splenocytes in the G0/G1 phase, which was accompanied by inhibition of the expression of the positive regulators CDK4, CDK2, cyclin D1, PCNA, and E2F1, and promotion of the expression of the negative regulators p53, p21 Waf1/Cip1, p27 Kip1, and Chk1. We also found that Euptox A did not markedly induce splenocyte apoptosis, but induced autophagy while increasing the subcellular localization of punctate LC3, ratio of LC3-II/LC3-I, and Beclin 1 levels, and decreasing p62 levels. Euptox A also significantly inhibited p-PI3K, p-p38 MAPK, p-Akt, and p-mTOR expression, but increased PTEN and p-AMPK expression. These results indicated that Euptox A induced splenocyte autophagy by inhibiting the PI3K/Akt/mTOR pathway, suppressing p38 MAPK expression, and activating AMPK. These findings provide new insights into the mechanisms involved in spleen toxicity caused by Euptox A in mice.


Assuntos
Autofagia/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sesquiterpenos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Baço/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Ageratina/química , Animais , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Baço/citologia , Baço/metabolismo , Relação Estrutura-Atividade
7.
AMB Express ; 7(1): 98, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28510221

RESUMO

The conventional procedure for the construction of recombinant expression vector of a target gene includes PCR cloning and restriction enzyme mediated subcloning, which is time-consuming and sometimes troublesome because of the inefficiency of ligation. A variety of ligase-independent PCR cloning strategies have been developed, but they either involve complicated PCR procedures or need other DNA modifying enzymes. In this study, we report the design, and construction of an omnipotent expression vector pOmni, with which a target gene can be easily cloned through innovative selection-free PCR recombination cloning strategy with only one pair of primer and two times of PCR in one work day, without using any restriction enzymes, ligase and other DNA modifying enzymes. Furthermore, the target gene cloned in pOmni is ready to be high-efficiently expressed in either Escherichia coli cells or eukaryotic cells because of the elaborate design of compatible T7 promoter and CMV promoter expression elements in the vector. The cloning capability and reliability of selection-free PCR recombination cloning with pOmni were validated through cloning of 6 DNA fragments with length from 315 to 4557 bp, and the dual-expression function of the vector was verified through the cloning and expression of EGFP in E. coli BL21 and HeLa cells. pOmni developed in our study provides a powerful tool for gene cloning and expression, and is of special value for researches in which both prokaryotic and eukaryotic expression of a target gene are necessary.

8.
Sci Rep ; 5: 15967, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26527166

RESUMO

The precise cytotoxicity of E. Adenophorum in relation to the cell cycle and apoptosis of splenocytes in Saanen goats remains unclear. In the present study, 16 Saanen goats were randomly divided into four groups, which were fed on 0%, 40%, 60% and 80% E. adenophorum diets. The results of TUNEL, DAPI and AO/EB staining, flow cytometry analysis and DNA fragmentation assays showed that E. adenophorum induced typical apoptotic features in splenocytes, suppressed splenocyte viability, and caused cell cycle arrest in a dose-dependent manner. However, westernblot, ELISA, qRT-PCR and caspase activity analyses showed that E. adenophoruminhibited Bcl-2 expression, promoted Bax translocation to the mitochondria, triggered the release of Cytc from the mitochondria into the cytosol, and activated caspase-9 and -3 and the subsequent cleavage of PARP. Moreover, in E. adenophorum-induced apoptosis, the protein levels of Fas, Bid, FasL and caspase-8 showed no significant changes. E. adenophorum treatment induced the collapse of ΔΨm. Moreover, these data suggested that E. adenophorum induces splenocyte apoptosis via the activation of the mitochondrial apoptosis pathway in splenocytes. These findings provide new insights into the mechanisms underlying the effects of E. adenophorum cytotoxicity on splenocytes.


Assuntos
Ageratina/química , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Preparações de Plantas/farmacologia , Animais , Apoptose/genética , Western Blotting , Caspases/genética , Pontos de Checagem do Ciclo Celular/genética , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Feminino , Expressão Gênica/efeitos dos fármacos , Cabras , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Folhas de Planta/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/citologia , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
9.
PLoS One ; 10(9): e0138504, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26382060

RESUMO

The cytotoxicity effects of E. adenophorum on cell cycle and apoptosis of renal cells in Saanen goat was evaluated by TUNEL, DAPI, AO/EB staining, DNA fragmentation assay, Caspase activity, Western-blot, qRT-PCR and flow cytometry analysis. 16 saanen goats randomly divided into four groups were fed on 0%, 40%, 60% and 80% E. adenophorum diets. The Results showed that E. adenophorum induced typical apoptotic features of renal cells. E. adenophorum significantly suppressed renal cells viability, caused cell cycle activity arrest and induced typical apoptotic features in a dose-dependent manner. However, the protein levels of Fas/FasL, Bid and caspase-8 did not appear significant changes in the process of E. adenophorum-induced apoptosis. Moreover, E. adenophorum administration slightly decreased Bcl-2 expression, promoted Bax translocation to mitochondria, triggered the release of Cyt c from mitochondria into cytosol and activated caspase-9, -3, and cleaved PARP. The mitochondrial p53 translocation was significantly activated, accompanied by a significant increase in the loss of ΔΨm, Cyt c release and caspase-9 activation. Above all, these data suggest that E. adenophorum induces renal cells apoptosis via the activation of mitochondria-mediated apoptosis pathway in renal cells. These findings may provide new insights to understand the mechanisms involved in E. adenophorum-caused cytotoxicity of renal cells.


Assuntos
Ageratina , Apoptose/fisiologia , Caspases/metabolismo , Ciclo Celular/fisiologia , Rim/metabolismo , Mitocôndrias/metabolismo , Animais , Pontos de Checagem do Ciclo Celular/fisiologia , Cabras , Rim/citologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
10.
Exp Ther Med ; 10(1): 247-250, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26170943

RESUMO

The aim of the present study was to investigate the acaricidal activity of Ligularia virgaurea. An extract was prepared by refluxing with ethanol and steam distillation, and its toxic effect was tested in vitro against Sarcoptes scabiei. The data from the toxicity tests were analyzed using a complementary log-log (CLL) model. The ethanol extract exhibited strong acaricidal activity against these mites; at a concentration of 2 g/ml it killed all S. scabiei within 2 h and at 1 g/ml it killed all S. scabiei within 6 h. Similarly, 2, 1, 0.5 and 0.25 g/ml concentrations of the extract had strong toxicity against S. scabiei, with median lethal time (LT50) values of 0.716, 1.741, 2.968 and 4.838 h, respectively. The median lethal concentration (LC50) values were 1.388, 0.624, 0.310 and 0.213 g/ml for Scabies mite in 1, 2, 4 and 6 h, respectively. The results indicate that the L. virgaurea extract has strong acaricidal activity and may be exploited as a novel treatment for the effective control of acariasis in animals.

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