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1.
Nature ; 632(8025): 576-584, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38866052

RESUMO

Increasing planting density is a key strategy for enhancing maize yields1-3. An ideotype for dense planting requires a 'smart canopy' with leaf angles at different canopy layers differentially optimized to maximize light interception and photosynthesis4-6, among other features. Here we identified leaf angle architecture of smart canopy 1 (lac1), a natural mutant with upright upper leaves, less erect middle leaves and relatively flat lower leaves. lac1 has improved photosynthetic capacity and attenuated responses to shade under dense planting. lac1 encodes a brassinosteroid C-22 hydroxylase that predominantly regulates upper leaf angle. Phytochrome A photoreceptors accumulate in shade and interact with the transcription factor RAVL1 to promote its degradation via the 26S proteasome, thereby inhibiting activation of lac1 by RAVL1 and decreasing brassinosteroid levels. This ultimately decreases upper leaf angle in dense fields. Large-scale field trials demonstrate that lac1 boosts maize yields under high planting densities. To quickly introduce lac1 into breeding germplasm, we transformed a haploid inducer and recovered homozygous lac1 edits from 20 diverse inbred lines. The tested doubled haploids uniformly acquired smart-canopy-like plant architecture. We provide an important target and an accelerated strategy for developing high-density-tolerant cultivars, with lac1 serving as a genetic chassis for further engineering of a smart canopy in maize.


Assuntos
Produção Agrícola , Fotossíntese , Folhas de Planta , Zea mays , Brassinosteroides/metabolismo , Produção Agrícola/métodos , Escuridão , Haploidia , Homozigoto , Luz , Mutação , Fotossíntese/efeitos da radiação , Fitocromo A/metabolismo , Melhoramento Vegetal , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Fatores de Transcrição/metabolismo , Zea mays/anatomia & histologia , Zea mays/enzimologia , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/efeitos da radiação
2.
Anal Chem ; 96(17): 6683-6691, 2024 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-38619493

RESUMO

Hydrogen peroxide (H2O2) and ascorbic acid (AA), acting as two significant indicative species, correlate with the oxidative stress status in living brains, which have historically been considered to be involved mainly in neurodegenerative disorders such as Alzheimer's disease, Huntington's disease, and Parkinson's disease (PD). The development of efficient biosensors for the simultaneous measurement of their levels in living brains is vital to understand their roles played in the brain and their interactive relationship in the progress of these diseases. Herein, a robust ratiometric electrochemical microsensor was rationally designed to realize the determination of H2O2 and AA simultaneously. Therefore, a specific probe was designed and synthesized with both recognition units responsible for reacting with H2O2 to produce a detectable signal on the microsensor and linkage units helping the probe modify onto the carbon substrate. A topping ingredient, single-walled carbon nanotubes (SWCNTs) was added on the surface of the electrode, with the purpose of not only facilitating the oxidation of AA but also absorbing methylene blue (MB), prompting to read out the inner reference signal. This proposed electrochemical microsensor exhibited a robust ability to real-time track H2O2 and AA in linear ranges of 0.5-900 and 10-1000 µM with high selectivity and accuracy, respectively. Eventually, the efficient electrochemical microsensor was successfully applied to the simultaneous measurement of H2O2 and AA in the rat brain, followed by microinjection, and in the PD mouse brain.


Assuntos
Ácido Ascórbico , Encéfalo , Técnicas Eletroquímicas , Peróxido de Hidrogênio , Nanotubos de Carbono , Peróxido de Hidrogênio/análise , Ácido Ascórbico/análise , Animais , Camundongos , Encéfalo/metabolismo , Nanotubos de Carbono/química , Técnicas Biossensoriais , Eletrodos
3.
Exp Gerontol ; 188: 112387, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38431178

RESUMO

OBJECTIVE: Dysregulation of covalently closed circular RNAs (circRNAs) has been associated with neurological disorders, the role of circHIVP2 in Parkinson's disease (PD) and its molecular mechanism is not well understood. METHODS: 127 patients with PD and 85 healthy people were enrolled. RT-qPCR was employed to examine the levels of circHIVEP2. ROC curve to explore the diagnostic. Mpp+ induced the SH-SY5Y to construct an in vitro PD cell model. Cell viability, apoptosis, and secretion levels of inflammatory factors were analyzed by CCK-8, flow cytometry, and ELISA assay. CircHIVEP2 targets miRNA predicted by bioinformatics database and validated by the dual luciferase reporter and RIP assays. RESULTS: CircHIVEP2 was typically lower in PD patients than in controls. CircHIVEP2 has certain specificity and sensitivity to recognize PD patients from healthy individuals. miR-485-3p, a target miRNA of circHIVEP2, was significantly elevated in PD patients. Additionally, MPP+ induction reduced cell viability and promoted apoptosis and inflammatory factor overproduction. However, overexpression of circHIVEP2 significantly inhibited the effects of MPP+, but this inhibition was significantly attenuated by elevated miR-485-3p. CONCLUSION: circHIVEP2 is a potential diagnostic biomarker for PD, and its upregulation mitigated MPP+-induced nerve damage and inflammation and this may be through targeted by the miR-485-3p.


Assuntos
MicroRNAs , Neuroblastoma , Doença de Parkinson , Humanos , Doença de Parkinson/genética , 1-Metil-4-fenilpiridínio/farmacologia , Linhagem Celular Tumoral , MicroRNAs/genética , Apoptose
4.
Poult Sci ; 103(8): 103850, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38838589

RESUMO

Follicle selection in chicken refers to the process of selecting a follicle to enter hierarchy from a cohort of small yellow follicles (SY) with a diameter of 6 to 8 mm. The follicle being selected will develop rapidly and ovulate. Follicle selection is a key stage affecting chicken egg-laying performance. Our previous study showed that the phosphorylation level of lysine (K)-specific demethylase 1A (LSD1) at serine 54 (LSD1Ser54p) was significantly increased in F6 follicles compared to prehierarchal SY follicles, but its function was unclear. Here, the mechanism of this modification, the effect of LSD1Ser54p dephosphorylation on gene expression profile of chicken hierarchal granulosa cells and the function of fibroblast growth factor 9 (FGF9) that is regulated by LSD1Ser54p were further investigated. The modification of LSD1Ser54p was predicted to be mediated by cyclin-dependent kinase 5 (CDK5) and glycogen synthase kinase 3 (GSK3). Treatment of chicken hierarchal granulosa cells with CDK5 inhibitor significantly decreased LSD1Ser54p level (P < 0.05) and LSD1Ser54p interacted with CDK5, suggesting that, in the granulosa cells of chicken hierarchal follicles, LSD1Ser54p modification was carried out by CDK5. When the LSD1Ser54p level decreased in the granulosa cells of chicken hierarchal follicles, both the mRNA expression of FGF9 and α-actinin 2 (ACTN2) and the H3K4me2 level in their promoter regions significantly increased (P < 0.05), indicating that this phosphorylation modification enhanced the demethylation activity of LSD1. Moreover, in chicken hierarchal granulosa cells, overexpression of chicken FGF9 stimulated their proliferation and increased the mRNA expression of hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 1 (Hsd3b) and steroidogenic acute regulatory protein (StAR). This study collectively revealed that phosphorylation of LSD1 at serine 54 by CDK5 enhanced its demethylation activity in chicken ovarian granulosa cells and regulated genes including FGF9 that is engaged in chicken follicle selection.


Assuntos
Proteínas Aviárias , Galinhas , Células da Granulosa , Histona Desmetilases , Folículo Ovariano , Animais , Feminino , Células da Granulosa/metabolismo , Galinhas/genética , Histona Desmetilases/metabolismo , Histona Desmetilases/genética , Folículo Ovariano/metabolismo , Fosforilação , Proteínas Aviárias/metabolismo , Proteínas Aviárias/genética , Desmetilação , Regulação da Expressão Gênica/efeitos dos fármacos , Serina/metabolismo
5.
J Colloid Interface Sci ; 661: 401-408, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38306749

RESUMO

The electrocatalytic reduction of nitrite to recyclable ammonia (NH3) is essential to maintain nitrogen balance and meet growing energy requirements. Herein, we report that Ru doped honeycomb NiMoO4 nanosheet with copious oxygen vacancies grown on nickel foam substrate has been prepared by a facile hydrothermal synthesis and immersion process, which can act as an efficient electrocatalyst for NH3 synthesis by reduction of nitrite. By optimizing the concentration of RuCl3 solution, 0.01Ru-NiMoO4/NF possesses excellent NO2-RR performance with NH3 yield of 20249.17 ± 637.42 µg h-1 cm-2 at -0.7 V and FE of 95.56 ± 0.72 % at -0.6 V. When assembled into a Zn-NO2- battery, it provides a remarkable level of power density of 13.89 mW cm-2, outperforming the performance of virtually all previous reports. The efficient adsorption and activation of NO2- over Ru-doped NiMoO4 with oxygen vacancy have been verified by density functional theory calculations, as well as the possible reaction pathway.

6.
Mol Med Rep ; 30(3)2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38963022

RESUMO

As sequencing technology transitions from research to clinical settings, due to technological maturity and cost reductions, metagenomic next­generation sequencing (mNGS) is increasingly used. This shift underscores the growing need for more cost­effective and universally accessible sequencing assays to improve patient care and public health. Therefore, targeted NGS (tNGS) is gaining prominence. tNGS involves enrichment of target pathogens in patient samples based on multiplex PCR amplification or probe capture with excellent sensitivity. It is increasingly used in clinical diagnostics due to its practicality and efficiency. The present review compares the principles of different enrichment methods. The high positivity rate of tNGS in the detection of pathogens was found in respiratory samples with specific instances. tNGS maintains high sensitivity (70.8­95.0%) in samples with low pathogen loads, including blood and cerebrospinal fluid. Furthermore, tNGS is effective in detecting drug­resistant strains of Mycobacterium tuberculosis, allowing identification of resistance genes and guiding clinical treatment decisions, which is difficult to achieve with mNGS. In the present review, the application of tNGS in clinical settings and its current limitations are assessed. The continued development of tNGS has the potential to refine diagnostic accuracy and treatment efficacy and improving infectious disease management. However, further research to overcome technical challenges such as workflow time and cost is required.


Assuntos
Doenças Transmissíveis , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/microbiologia , Doenças Transmissíveis/genética , Metagenômica/métodos , Técnicas de Diagnóstico Molecular/métodos
7.
Front Microbiol ; 15: 1408645, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38894966

RESUMO

Introduction: Carbohydrates, which make up 20 to 25% of tea beverages, are responsible for their flavor and bioactivity. Carbohydrates of pu-erh tea change during microbial fermentation and require further research. In this study, we examined the carbohydrate metabolism and expression of carbohydrate-active enzyme genes during the fermentation of tea leaves with Aspergillus luchuensis. Methods: Widely targeted metabolomics analysis, high-performance anion-exchange chromatography measurements, and transcriptomics were used in this study. Results: After fermentation, the levels of soluble sugar, hemicellulose, lignin, eight monosaccharides, and seven sugar alcohols increased. Meanwhile, the relative contents of polysaccharides, D-sorbitol, D-glucose, and cellulose decreased. High expression of 40 genes encoding 16 carbohydrate enzymes was observed during fermentation (FPKM>10). These genes encode L-iditol 2-dehydrogenase, pectinesterase, polygalacturonase, α-amylase, glucoamylase, endoglucanase, ß-glucosidase, ß-galactosidase, α-galactosidase, α-glucosidase, and glucose-6-phosphate isomerase, among others. Discussion: These enzymes are known to break down polysaccharides and cell wall cellulose, increasing the content of monosaccharides and soluble sugars.

8.
Food Chem X ; 20: 101003, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38144832

RESUMO

"Ancient tea plants" are defined as tea trees > 100 years old, or with a trunk diameter > 25 cm; their leaves are manufactured to high - quality, valuable ancient plants pu-erh tea (APPT). In this study, a fermentation of APPT were developed, and outstanding sweetness of APPT infusion was observed. During fermentation, the content of soluble sugars, theabrownins (p < 0.05), as well as 41 metabolites were increased [Variable importance in projection (VIP) > 1.0; p < 0.05 and Fold-change (FC) FC > 2]; While relative levels of 72 metabolites were decreased (VIP > 1.0, p < 0.05 and FC < 0.5. Staphylococcus, Achromobacter, Sphingomonas, Thermomyces, Rasamsonia, Blastobotrys, Aspergillus and Cladosporium were identified as dominant genera, and their relative levels were correlated with contents of characteristic components (p < 0.05). Together, changes in sensory characteristics, chemical composition and microbial succession during APPT fermentation were investigated, and advanced the formation mechanism of its unique quality.

9.
Int. braz. j. urol ; 40(6): 846-852, Nov-Dec/2014. tab
Artigo em Inglês | LILACS | ID: lil-735980

RESUMO

There is a lack of definitive information regarding the precise indications, implementation, and outcomes of continuous renal replacement therapy (CRRT) for the treatment of critically ill children. Six children (three boys, three girls) aged from 3 days to 8 years, all of whom had multiple organ failure, were submitted to bedside CRRT using M60 filter membranes. Modified Port carbonate formula was used and clotting time was maintained between 20 and 30 minutes. Activated partial thromboplastin time was 1.5- to 2-fold normal. One patient discontinued treatment due to family decision. Marked improvements were seen in the remaining five patients, including normalization of blood urea nitrogen and creatinine levels, stabilization of electrolytes, and improvements in markers of organ function. Of note, one patient (a six-year-old male) underwent the treatment for 241 hours. All five patients were subsequently discharged and recovered uneventfully. CRRT is effective for the management of children who are critically ill due to multiple organ failure.


Assuntos
Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Insuficiência de Múltiplos Órgãos/terapia , Terapia de Substituição Renal/métodos , Injúria Renal Aguda/terapia , Cuidados Críticos , Estado Terminal , Unidades de Terapia Intensiva Pediátrica , Insuficiência de Múltiplos Órgãos/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
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