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1.
Nature ; 612(7941): 673-678, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36450987

RESUMO

Electrochemical saline water electrolysis using renewable energy as input is a highly desirable and sustainable method for the mass production of green hydrogen1-7; however, its practical viability is seriously challenged by insufficient durability because of the electrode side reactions and corrosion issues arising from the complex components of seawater. Although catalyst engineering using polyanion coatings to suppress corrosion by chloride ions or creating highly selective electrocatalysts has been extensively exploited with modest success, it is still far from satisfactory for practical applications8-14. Indirect seawater splitting by using a pre-desalination process can avoid side-reaction and corrosion problems15-21, but it requires additional energy input, making it economically less attractive. In addition, the independent bulky desalination system makes seawater electrolysis systems less flexible in terms of size. Here we propose a direct seawater electrolysis method for hydrogen production that radically addresses the side-reaction and corrosion problems. A demonstration system was stably operated at a current density of 250 milliamperes per square centimetre for over 3,200 hours under practical application conditions without failure. This strategy realizes efficient, size-flexible and scalable direct seawater electrolysis in a way similar to freshwater splitting without a notable increase in operation cost, and has high potential for practical application. Importantly, this configuration and mechanism promises further applications in simultaneous water-based effluent treatment and resource recovery and hydrogen generation in one step.

2.
Nature ; 577(7789): 199-203, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31915396

RESUMO

Bulk amorphous materials have been studied extensively and are widely used, yet their atomic arrangement remains an open issue. Although they are generally believed to be Zachariasen continuous random networks1, recent experimental evidence favours the competing crystallite model in the case of amorphous silicon2-4. In two-dimensional materials, however,  the corresponding questions remain unanswered. Here we report the synthesis, by laser-assisted chemical vapour deposition5, of centimetre-scale, free-standing, continuous and stable monolayer amorphous carbon, topologically distinct from disordered graphene. Unlike in bulk materials, the structure of monolayer amorphous carbon can be determined by atomic-resolution imaging. Extensive characterization by Raman and X-ray spectroscopy and transmission electron microscopy reveals the complete absence of long-range periodicity and a threefold-coordinated structure with a wide distribution of bond lengths, bond angles, and five-, six-, seven- and eight-member rings. The ring distribution is not a Zachariasen continuous random network, but resembles the competing (nano)crystallite model6. We construct a corresponding model that enables density-functional-theory calculations of the properties of monolayer amorphous carbon, in accordance with observations. Direct measurements confirm that it is insulating, with resistivity values similar to those of boron nitride grown by chemical vapour deposition. Free-standing monolayer amorphous carbon is surprisingly stable and deforms to a high breaking strength, without crack propagation from the point of fracture. The excellent physical properties of this stable, free-standing monolayer amorphous carbon could prove useful for permeation and diffusion barriers in applications such as magnetic recording devices and flexible electronics.

3.
J Biol Chem ; 300(10): 107765, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39276936

RESUMO

Loss of terminal differentiation is a hallmark of cancer and offers a potential mechanism for differentiation therapy. Polycomb repressive complex 2 (PRC2) serves as the methyltransferase for K27 of histone H3 that is crucial in development. While PRC2 inhibitors show promise in treating various cancers, the underlying mechanisms remain incompletely understood. Here, we demonstrated that the inhibition or depletion of PRC2 enhanced adipocyte differentiation in malignant rhabdoid tumors and mesenchymal stem cells, through upregulation of peroxisome proliferator-activated receptor gamma (PPARG) and CEBPA. Mechanistically, PRC2 directly represses their transcription through H3K27 methylation, as both genes exhibit a bivalent state in mesenchymal stem cells. KO of PPARG compromised C/EBPα expression and impeded the PRC2 inhibitor-induced differentiation into adipocytes. Furthermore, the combination of the PPARγ agonist rosiglitazone and the PRC2 inhibitor MAK683 exhibited a higher inhibition on Ki67 positivity in tumor xenograft compared to MAK683 alone. High CEBPA, PLIN1, and FABP4 levels positively correlated with favorable prognosis in sarcoma patients in The Cancer Genome Atlas cohort. Together, these findings unveil an epigenetic regulatory mechanism for PPARG and highlight the essential role of PPARγ and C/EBPα in the adipocyte differentiation of malignant rhabdoid tumors and sarcomas with a potential clinical implication.

4.
Plant Physiol ; 196(2): 1284-1297, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38991561

RESUMO

Hybrid plants are found extensively in the wild, and they often demonstrate superior performance of complex traits over their parents and other selfing plants. This phenomenon, known as heterosis, has been extensively applied in plant breeding for decades. However, the process of decoding hybrid plant genomes has seriously lagged due to the challenges associated with genome assembly and the lack of appropriate methodologies for their subsequent representation and analysis. Here, we present the assembly and analysis of 2 hybrids, an intraspecific hybrid between 2 maize (Zea mays ssp. mays) inbred lines and an interspecific hybrid between maize and its wild relative teosinte (Z. mays ssp. parviglumis), utilizing a combination of PacBio High Fidelity sequencing and chromatin conformation capture sequencing data. The haplotypic assemblies are well phased at chromosomal scale, successfully resolving the complex loci with extensive parental structural variations (SVs). By integrating into a biparental genome graph, the haplotypic assemblies can facilitate downstream short-read-based SV calling and allele-specific gene expression analysis, demonstrating outstanding advantages over a single linear genome. Our work offers a comprehensive workflow that aims to facilitate the decoding of numerous hybrid plant genomes, particularly those with unknown or inaccessible parentage, thereby enhancing our understanding of genome evolution and heterosis.


Assuntos
Genoma de Planta , Hibridização Genética , Zea mays , Genoma de Planta/genética , Zea mays/genética , Vigor Híbrido/genética , Melhoramento Vegetal/métodos
5.
J Neurosci ; 43(28): 5241-5250, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37365003

RESUMO

Many sleep less than recommended without experiencing daytime sleepiness. According to prevailing views, short sleep increases risk of lower brain health and cognitive function. Chronic mild sleep deprivation could cause undetected sleep debt, negatively affecting cognitive function and brain health. However, it is possible that some have less sleep need and are more resistant to negative effects of sleep loss. We investigated this using a cross-sectional and longitudinal sample of 47,029 participants of both sexes (20-89 years) from the Lifebrain consortium, Human Connectome project (HCP) and UK Biobank (UKB), with measures of self-reported sleep, including 51,295 MRIs of the brain and cognitive tests. A total of 740 participants who reported to sleep <6 h did not experience daytime sleepiness or sleep problems/disturbances interfering with falling or staying asleep. These short sleepers showed significantly larger regional brain volumes than both short sleepers with daytime sleepiness and sleep problems (n = 1742) and participants sleeping the recommended 7-8 h (n = 3886). However, both groups of short sleepers showed slightly lower general cognitive function (GCA), 0.16 and 0.19 SDs, respectively. Analyses using accelerometer-estimated sleep duration confirmed the findings, and the associations remained after controlling for body mass index, depression symptoms, income, and education. The results suggest that some people can cope with less sleep without obvious negative associations with brain morphometry and that sleepiness and sleep problems may be more related to brain structural differences than duration. However, the slightly lower performance on tests of general cognitive abilities warrants closer examination in natural settings.SIGNIFICANCE STATEMENT Short habitual sleep is prevalent, with unknown consequences for brain health and cognitive performance. Here, we show that daytime sleepiness and sleep problems are more strongly related to regional brain volumes than sleep duration. However, participants sleeping ≤6 h had slightly lower scores on tests of general cognitive function (GCA). This indicates that sleep need is individual and that sleep duration per se is very weakly if at all related brain health, while daytime sleepiness and sleep problems may show somewhat stronger associations. The association between habitual short sleep and lower scores on tests of general cognitive abilities must be further scrutinized in natural settings.


Assuntos
Distúrbios do Sono por Sonolência Excessiva , Transtornos do Sono-Vigília , Masculino , Feminino , Humanos , Estudos Transversais , Encéfalo/diagnóstico por imagem , Sono , Privação do Sono/diagnóstico por imagem , Transtornos do Sono-Vigília/complicações , Cognição , Distúrbios do Sono por Sonolência Excessiva/complicações , Distúrbios do Sono por Sonolência Excessiva/diagnóstico
6.
Anal Chem ; 96(28): 11533-11541, 2024 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-38973171

RESUMO

In the landscape of biomolecular detection, surface-enhanced Raman spectroscopy (SERS) confronts notable obstacles, particularly in the label-free detection of biomolecules, with glucose and other sugars presenting a quintessential challenge. This study heralds the development of a pioneering SERS substrate, ingeniously engineered through the self-assembly of nanoparticles of diverse sizes (Ag1@Ag2NPs). This configuration strategically induces 'hot spots' within the interstices of nanoparticles, markedly amplifying the detection signal. Rigorous experimental investigations affirm the platform's rapidity, precision, and reproducibility, and the detection limit of this detection method is calculated to be 6.62 pM. Crucially, this methodology facilitates nondestructive glucose detection in simulated samples, including phosphate-buffered saline and urine. Integrating machine learning algorithms with simulated serum samples, the approach adeptly discriminates between hypoglycemic, normoglycemic, and hyperglycemic states. Moreover, the platform's versatility extends to the detection and differentiation of monosaccharides, disaccharides, and methylated glycosides, underscoring its universality and specificity. Comparative Raman spectroscopic analysis of various carbohydrate structures elucidates the unique SERS characteristics pertinent to these molecules. This research signifies a major advance in nonchemical, label-free glucose determination with enhanced sensitivity via SERS, laying a new foundation for its application in precision medicine and advancing structural analysis in the sugar domain.


Assuntos
Glucose , Nanopartículas Metálicas , Análise Espectral Raman , Análise Espectral Raman/métodos , Nanopartículas Metálicas/química , Glucose/análise , Humanos , Prata/química , Propriedades de Superfície , Limite de Detecção , Glicemia/análise
7.
Anal Chem ; 96(24): 10038-10045, 2024 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-38847602

RESUMO

Ferroptosis is a pattern of cell death caused by iron-dependent accumulation of lipid peroxides and is closely associated with the occurrence and development of multiple diseases. Acrolein (ACR), one of the final metabolites of lipid peroxidation, is a reactive carbonyl species with strong biotoxicity. Effective detection of ACR is important for understanding its role in the progression of ferroptosis and studying the specific mechanisms of ferroptosis-mediated diseases. However, visualization detection of ACR during ferroptosis has not yet been reported. In this work, the first ratiometric fluorescent probe (HBT-SH) based on 2-(2'-hydroxyphenyl) benzothiazole (HBT) was designed for tracing endogenous ACR with an unprecedented regiospecific ACR-induced intramolecular cyclization strategy, which employs 2-aminoethanethiol as an ACR-selective recognition receptor. The experimental results showed that HBT-SH has excellent selectivity, high sensitivity (LOD = 0.26 µM) and good biocompatibility. More importantly, the upregulation of ACR levels was observed during ferroptosis in HeLa cells and zebrafish, indicating that ACR may be a specific active molecule that plays an essential biological role during ferroptosis or may serve as a potential marker of ferroptosis, which has great significance for studying the pathological process and treatment options of ferroptosis-related diseases.


Assuntos
Acroleína , Ferroptose , Corantes Fluorescentes , Peixe-Zebra , Ferroptose/efeitos dos fármacos , Acroleína/química , Acroleína/metabolismo , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Humanos , Células HeLa , Animais , Regulação para Cima/efeitos dos fármacos , Imagem Óptica , Estrutura Molecular
8.
Anal Chem ; 96(21): 8566-8575, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38748451

RESUMO

Unraveling bacterial identity through Raman scattering techniques has been persistently challenging due to homogeneously amplified Raman signals across a wide variety of bacterial molecules, predominantly protein- or nucleic acid-mediated. In this study, we present an approach involving the use of silver nanoparticles to completely and uniformly "mask" adsorption on the surface of bacterial molecules through sodium borohydride and sodium chloride. This approach enables the acquisition of enhanced surface-enhanced Raman scattering (SERS) signals from all components on the bacterial surface, facilitating rapid, specific, and label-free bacterial identification. For the first time, we have characterized the identity of a bacterium, including its DNA, metabolites, and cell walls, enabling the accurate differentiation of various bacterial strains, even within the same species. In addition, we embarked on an exploration of the origin and variability patterns of the main characteristic peaks of Gram-positive and Gram-negative bacteria. Significantly, the SERS peak ratio was found to determine the inflection point of accelerated bacterial death upon treatment with antimicrobials. We further applied this platform to identify 15 unique clinical antibiotic-resistant bacterial strains, including five Escherichia coli strains in human urine, a first for Raman technology. This work has profound implications for prompt and accurate identification of bacteria, particularly antibiotic-resistant strains, thereby significantly enhancing clinical diagnostics and antimicrobial treatment strategies.


Assuntos
Nanopartículas Metálicas , Prata , Análise Espectral Raman , Análise Espectral Raman/métodos , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/análise , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Escherichia coli/química , Humanos
9.
Small ; 20(44): e2403821, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38949043

RESUMO

Compared to the bulk heterojunction (BHJ) devices, the quasiplanar heterojunction (Q-PHJ) exhibits a more stable morphology and superior charge transfer performance. To achieve both high efficiency and long-term stability, it is necessary to design new materials for Q-PHJ devices. In this study, QxIC-CF3 and QxIC-CH3 are designed and synthesized for the first time. The trifluoromethylation of the central core exerts a modulatory effect on the molecular stacking pattern, leveraging the strong electrostatic potential and intermolecular interactions. Compared with QxIC-CH3, the single crystal structure reveals that QxIC-CF3 exhibits a more compact 2D linear stacking behavior. These benefits, combined with the separated electron and hole transport channels in Q-PHJ device, lead to increased charge mobility and reduced energy loss. The devices based on D18/QxIC-CF3 exhibit an efficiency of 18.1%, which is the highest power conversion efficiency (PCE) for Q-PHJ to date. Additionally, the thermodynamic stability of the active layer morphology enhances the lifespan of the aforementioned devices under illumination conditions. Specifically, the T80 is 420 h, which is nearly twice that of the renowned Y6-based BHJ device (T80 = 220 h). By combining the advantages of the trifluoromethylation and Q-PHJ device, efficient and stable organic solar cell devices can be constructed.

10.
Brain Behav Immun ; 120: 403-412, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38871062

RESUMO

Persistent psychological stress can affect immune homeostasis and is a key factor in the development of depression. Many efforts are focused on the identifcation of pathways that link the immune system and mood disorders. Here, we found that psychological stress caused an increase in the frequency of brain-associated neutrophils and the level of neutrophil-specific antigen CD177 on peripheral neutrophils in male mice. Upregulated levels of blood CD177 are associated with depression in humans. Neutrophil depletion or Cd177 deficiency protected mice from stress-induced behavioral deficits. Importantly, adoptive transfer of CD177+ neutrophils from stressed mice increased the frequency of brain-associated leukocytes, including neutrophils, and caused behavioral defects in naive mice. These effects may be related to the endothelial adhesion advantage of CD177+ neutrophils and the interference of serine protease on endothelial junction. Our findings suggest a critical link between circulating CD177+ neutrophils and psychological stress-driven behavioral disorder.


Assuntos
Comportamento Animal , Camundongos Endogâmicos C57BL , Neutrófilos , Estresse Psicológico , Animais , Humanos , Masculino , Camundongos , Comportamento Animal/fisiologia , Encéfalo/metabolismo , Depressão/metabolismo , Depressão/imunologia , Proteínas Ligadas por GPI/metabolismo , Neutrófilos/metabolismo , Receptores de Superfície Celular/metabolismo , Estresse Psicológico/metabolismo , Estresse Psicológico/imunologia
11.
Mol Psychiatry ; 28(7): 3111-3120, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37165155

RESUMO

The difference between chronological age and the apparent age of the brain estimated from brain imaging data-the brain age gap (BAG)-is widely considered a general indicator of brain health. Converging evidence supports that BAG is sensitive to an array of genetic and nongenetic traits and diseases, yet few studies have examined the genetic architecture and its corresponding causal relationships with common brain disorders. Here, we estimate BAG using state-of-the-art neural networks trained on brain scans from 53,542 individuals (age range 3-95 years). A genome-wide association analysis across 28,104 individuals (40-84 years) from the UK Biobank revealed eight independent genomic regions significantly associated with BAG (p < 5 × 10-8) implicating neurological, metabolic, and immunological pathways - among which seven are novel. No significant genetic correlations or causal relationships with BAG were found for Parkinson's disease, major depressive disorder, or schizophrenia, but two-sample Mendelian randomization indicated a causal influence of AD (p = 7.9 × 10-4) and bipolar disorder (p = 1.35 × 10-2) on BAG. These results emphasize the polygenic architecture of brain age and provide insights into the causal relationship between selected neurological and neuropsychiatric disorders and BAG.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Transtornos Mentais , Humanos , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Transtorno Depressivo Maior/genética , Estudo de Associação Genômica Ampla , Transtornos Mentais/genética , Encéfalo , Transtorno Bipolar/genética
12.
J Org Chem ; 89(12): 8851-8860, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38840313

RESUMO

A CuBr-catalyzed cross-coupling reaction of propargyl bromides with terminal alkynes for the synthesis of 1, n-diynes was investigated. In N,N-dimethylacetamide (DMAc), the cross-coupling reactions of 3-bromo-1-arylpropynes, 3-bromo-1-phenyl-butyne/pentyne with aromatic terminal alkynes in the presence of CuBr and K3PO4 under nitrogen at 40 °C occur to give 1, 5-diaryl-1, 4-diynes having 3-CH2/3-CHMe/3-CHEt/3-CHiPr moieties with high chemoselectivity. Under similar reaction conditions, either the reactions of 3-bromo-1-arylpropynes with aliphatic terminal alkynes or the reactions of 3-bromo-1-alkylpropynes with aromatic terminal alkynes afforded the unexpected unsymmetric 1, 4-disubstituted 1, 3-diynes through one of the alkynyl group shifts to the side conjugating with the aryl group; in these cases, 1, 5-disubstituted 1, 4-diynes could not be obtained at all. In addition, when 3-bromo-1-phenyl-butynes react with aliphatic terminal alkynes bearing a distal phenyl group, the formed 1, 4-diynes are expected not to undergo the alkynyl group shift due to the methyl group at 3-position to form 1, 3-diynes; however, 1, 4-diynes could not be obtained either, and the 1, 5-, 1, 6-, and 1, 7-diynes, by an unprecedented remote alkynyl shift to the side conjugating with the aryl group, were isolated from the reaction mixtures in good yields.

13.
Analyst ; 149(9): 2526-2541, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38623605

RESUMO

Surface-enhanced Raman spectroscopy (SERS) has emerged as an indispensable analytical tool in biomolecular research, providing unmatched sensitivity critical for the elucidation of biomolecular structures. This review presents a thorough examination of SERS, outlining its fundamental principles, cataloging its varied applications within the biomolecular sphere, and contemplating its future developmental trajectories. We begin with a detailed analysis of SERS's mechanistic principles, emphasizing both the phenomena of surface enhancement and the complexities inherent in Raman scattering spectroscopy. Subsequently, we delve into the pivotal role of SERS in the structural analysis of diverse biomolecules, including proteins, nucleic acids, lipids, carbohydrates, and biochromes. The remarkable capabilities of SERS extend beyond mere detection, offering profound insights into biomolecular configurations and interactions, thereby enriching our comprehension of intricate biological processes. This review also sheds light on the application of SERS in real-time monitoring of various bio-relevant compounds, from enzymes and coenzymes to metal ion-chelate complexes and cellular organelles, thereby providing a holistic view and empowering researchers to unravel the complexities of biological systems. We also address the current challenges faced by SERS, such as enhancing sensitivity and resolution, developing stable and reproducible substrates, and conducting thorough analyses in complex biological matrices. Nonetheless, the continual advancements in nanotechnology and spectroscopy solidify the standing of SERS as a formidable force in biomolecular research. In conclusion, the versatility and robustness of SERS not only deepen our understanding of biomolecular intricacies but also pave the way for significant developments in medical research, therapeutic innovation, and diagnostic approaches.


Assuntos
Análise Espectral Raman , Análise Espectral Raman/métodos , Humanos , Proteínas/análise , Proteínas/química , Ácidos Nucleicos/análise , Ácidos Nucleicos/química , Propriedades de Superfície , Animais
14.
J Chem Inf Model ; 64(19): 7698-7708, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39327929

RESUMO

Nucleic acid aptamers possess unique advantages in specific recognition. However, the lack of in-depth investigation into their dynamic recognition mechanisms has restricted their rational design and potential applications in fields such as biosensing and targeted therapy. We herein utilized enhanced sampling molecular dynamics to address affinities of adenosine monophosphate (AMP) to the dual binding sites in the DNA aptamer, focusing on the dynamic recognition mechanism and pathways. The present results indicate that in addition to the widely known intermolecular interactions, inequivalence of chemical environments of the two binding sites leads to slightly higher stability of AMP binding to the site proximal to the aptamer terminus. In the presence of two AMPs captured by the two sites, each binding free energy is enhanced. In particular, an additional hydrogen bond of AMP to A10 is introduced in the dual-site binding complex, which increases the binding energy from -4.25 ± 0.47 to -9.48 ± 0.33 kcal mol-1 in the site close to the loop. For the dual-site recognition process, the free energy landscape and minimum free energy pathway calculations elucidate the crucial role of electrostatic interactions between the AMP phosphate groups and Na+ ions in positively cooperative binding mechanisms.


Assuntos
Monofosfato de Adenosina , Aptâmeros de Nucleotídeos , Simulação de Dinâmica Molecular , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Sítios de Ligação , Monofosfato de Adenosina/química , Termodinâmica , Conformação de Ácido Nucleico , Ligação de Hidrogênio
15.
Phys Chem Chem Phys ; 26(25): 17622-17630, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38864339

RESUMO

The in vitro detection applications of europium complex-doped microspheres mainly rely on strong fluorescence intensity and a well-defined morphology. In this work, using methyl methacrylate-modified polystyrene microspheres has been proven an effective strategy to enhance the fluorescence and morphology of Eu-complexes. The experimental results showed that the modification resulted in the formation of a porous structure within the polystyrene microspheres, enhancing the doping uniformity and facilitating a more significant accumulation of fluorescent molecules. Furthermore, because of their encapsulation ability, microspheres efficiently confine the fluorescent molecules within them. In addition, the nano-scale porous structure endowed the microspheres with enhanced properties without compromising solvent swelling capability, thereby significantly boosting the fluorescence performance of porous PSMMA. In lateral flow immunoassays (LFIAs), PSMMA-Eu microspheres were effectively utilized to detect fentanyl with exceptional sensitivity by capitalizing on these benefits, capable of detecting concentrations as low as 0.10 ng mL-1. This technology has significant potential for rapid point-of-care screening and clinical applications.

16.
Appl Microbiol Biotechnol ; 108(1): 327, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717623

RESUMO

Regulatory T cells (Tregs) are a subset of T cells participating in a variety of diseases including mycoplasmal pneumonia, contagious ecthyma, and so on. The role of Tregs in goat contagious ecthyma is not completely understood due to the lack of species-specific antibodies. Here, we developed a combination of CD4 and CD25 fluorescence monoclonal antibodies (mAb) to recognize goat Tregs and assessed its utility in flow cytometry, immunofluorescence staining. Using immunofluorescence staining, we found that the frequency of Treg cells was positively correlated with the viral load during orf virus infection. These antibodies could serve as important tools to monitor Tregs during orf virus infection in goats. KEY POINTS: • A combination of fluorescent mAbs (C11 and D12) was prepared for the detection of goat Tregs. • C11 and D12 are effective in flow cytometry, immunofluorescence staining, and C11 has excellent species specificity. • The frequency of Treg cells was positively correlated with the viral load during orf virus infection.


Assuntos
Anticorpos Monoclonais , Citometria de Fluxo , Cabras , Linfócitos T Reguladores , Carga Viral , Animais , Linfócitos T Reguladores/imunologia , Anticorpos Monoclonais/imunologia , Ectima Contagioso/diagnóstico , Ectima Contagioso/imunologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Vírus do Orf/imunologia , Imunofluorescência/métodos , Antígenos CD4/imunologia , Doenças das Cabras/imunologia , Doenças das Cabras/virologia , Doenças das Cabras/diagnóstico
17.
J Chem Phys ; 160(16)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38656441

RESUMO

In recent years, all-inorganic perovskite materials have become an ideal choice for new thin film solar cells due to their excellent photophysical properties and have become a research hotspot. Studying the ultrafast dynamics of photo-generated carriers is of great significance for further improving the performance of such devices. In this work, we focus on the transient dynamic process of CsPbBr3/TiO2 composite systems with different Mn2+ doping contents using femtosecond transient absorption spectroscopy technology. We used singular value decomposition and global fitting to analyze the transient absorption spectra and obtained three components, which are classified as hot carrier cooling, charge transfer, and charge recombination processes, respectively. We found that the doping concentration of Mn2+ has an impact on all three processes. We think that the following two factors are responsible: one is the density of defect states and the other is the bandgap width of perovskite. As the concentration of doped Mn2+ increases, the charge transfer time constant shows a trend of initially increasing, followed by a subsequent decrease, reaching a turning point. This indicates that an appropriate amount of Mn2+ doping can effectively improve the photoelectric performance of solar cell systems. We proposed a possible charge transfer mechanism model and further elucidated the microscopic mechanism of the effect of Mn2+ doping on the interface charge transfer process of the CsPbBr3/TiO2 solar cell system.

18.
Appl Opt ; 63(4): 967-975, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437393

RESUMO

Based on the principle of laser ablation and elastic vibration effect, a model of continuous nanosecond combined laser removal of rubber marks on a concrete surface was established. The model can explain the evolution of temperature, stress, and removal depth on time and laser energy density during laser cleaning. The results show that the theoretical adsorption force between the rubber layer and the concrete base is approximately 3.88×10-9 N. The continuous laser cleaning threshold is 561.31J/c m 2. In the combined laser, the continuous laser is 534.41J/c m 2, and the nanosecond laser is 0.35J/c m 2. As the delay time between the 2 ns laser beams increases, the maximum peak in the temperature curve gradually decreases. The optimal cleaning delay was obtained as Δ t=0.65S. The peak temperature at the characteristic position (0 µm, 0 µm) is 592.13 K, which is lower than the vaporization temperature of the rubber layer. The thermal stress values generated at this characteristic position exceed the adsorption stress values, indicating that the elastic removal mechanism is the main removal mechanism at the junction between the rubber layer and the concrete substrate.

19.
Biochem Genet ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635013

RESUMO

The family Sisoridae is one of the largest and most diverse Asiatic catfish families, with most species occurring in the water systems of the Qinhai-Tibetan Plateau and East Himalayas. At present, the phylogenetic relationship of the Sisoridae is relatively chaotic. In this study, the mitochondrial genomes (mitogenomes) of three species Creteuchiloglanis kamengensis, Glaridoglanis andersonii, and Exostoma sp. were systematically investigated, the phylogenetic relationships of the family were reconstructed and to determine the phylogenetic position of Exostoma sp. within Sisoridae. The lengths of the mitogenomes' sequences of C. kamengensis, G. andersonii, and Exostoma sp. were 16,589 bp, 16,531 bp, and 16,529 bp, respectively. They all contained one identical control region (D-loop), two ribosomal RNAs (rRNAs), 13 protein-coding genes (PCGs) and 22 transfer RNA (tRNA) genes. We applied two approaches, Bayesian Inference (BI) and Maximum Likelihood (ML), to construct phylogenetic trees. Our findings revealed that the topological structure of both ML and BI trees exhibited significant congruence. Specifically, the phylogenetic tree strongly supports the monophyly of Sisorinae and Glyptosternoids and provides new molecular biological data to support the reconstruction of phylogenetic relationships with Sisoridae. This study is of great scientific value for phylogenetic and genetic variation studies of the Sisoridae.

20.
Pestic Biochem Physiol ; 201: 105848, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685210

RESUMO

Fusarium asiaticum is a destructive phytopathogenic fungus that causes Fusarium head blight of wheat (FHB), leading to serious yield and economic losses to cereal crops worldwide. Our previous studies indicated that target-site mutations (K216R/E, S217P/L, or E420K/G/D) of Type I myosin FaMyo5 conferred high resistance to phenamacril. Here, we first constructed one sensitive strain H1S and three point mutation resistant strains HA, HC and H1R. Then we conducted comparative transcriptome analysis of these F. asiaticum strains after 1 and 10 µg·mL-1 phenamacril treatment. Results indicated that 2135 genes were differentially expressed (DEGs) among the sensitive and resistant strains. The DEGs encoding ammonium transporter MEP1/MEP2, nitrate reductase, copper amine oxidase 1, 4-aminobutyrate aminotransferase, amino-acid permease inda1, succinate-semialdehyde dehydrogenase, 2, 3-dihydroxybenzoic acid decarboxylase, etc., were significantly up-regulated in all the phenamacril-resistant strains. Compared to the control group, a total of 1778 and 2097 DEGs were identified in these strains after 1 and 10 µg·mL-1 phenamacril treatment, respectively. These DEGs involved in 4-aminobutyrate aminotransferase, chitin synthase 1, multiprotein-bridging factor 1, transcriptional regulatory protein pro-1, amino-acid permease inda1, ATP-dependent RNA helicase DED1, acetyl-coenzyme A synthetase, sarcoplasmic/endoplasmic reticulum calcium ATPase 2, etc., showed significantly down-regulated expression in phenamacril-sensitive strain but not in resistant strains after phenamacril treatment. In addition, cyanide hydratase, mating-type protein MAT-1, putative purine nucleoside permease, plasma membrane protein yro2, etc., showed significantly co-down-regulated expression in all the strains after phenamacril treatment. Taken together, This study provides deep insights into the resistance regulation mechanism and the inhibitory effect of fungicide phenamacril and these new annotated proteins or enzymes are worth for the discovery of new fungicide targets.


Assuntos
Farmacorresistência Fúngica , Fungicidas Industriais , Fusarium , Fusarium/efeitos dos fármacos , Fusarium/genética , Fungicidas Industriais/farmacologia , Farmacorresistência Fúngica/genética , Perfilação da Expressão Gênica , Transcriptoma/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Doenças das Plantas/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
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