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1.
Environ Res ; 263(Pt 1): 119995, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39276832

RESUMO

The poor remediation performance of groundwater circulation well (GCW) on semi-volatile organic contaminants (such as aniline) has severely limited its practical application. To address the challenges posed by the low volatility and solubility of these contaminants, an innovative integration of GCW with in-situ thermal remediation (ISTR) was proposed to create a thermal enhanced circulation well (GCW-ISTR) in this study. Laboratory experiments and model simulations were performed to evaluate the heat transfer and enhanced remediation effect by GCW-ISTR. Results demonstrate that the heat transfer process is controlled by the water circulation around GCW-ISTR and is influenced by factors such as aeration flow rate, groundwater velocity and aquifer permeability. Heating area is directly proportional to the seepage velocity of groundwater which can be analyzed by multiplying the water head difference between the upper and lower screens with the aquifer permeability. Therefore, the heat transfer model, based on Darcy's seepage theory and the energy conservation equation, effectively simulates the heat transfer with an error margin of less than 10%. Compared to individual GCW, GCW-ISTR exhibits a 25.8% improvement in aniline remediation efficiency, resulting in a decrease in the average concentration from 97.95 mg/L to 0.168 mg/L within 48 h, effectively mitigating the occurrence of tailing phenomena. This study provides a feasible method of enhancing the remediation of GCW on semi-volatile contaminants and is anticipated to broaden the applicability of GCW in site application.

2.
Appl Radiat Isot ; 214: 111515, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39276639

RESUMO

Boron Neutron Capture Therapy is being promoted with the development of accelerator neutron sources, and many new accelerator-based BNCT facilities are being built. In Particle Accelerator Facility project of Sun Yat-sen University, we plan to build a terminal for BNCT research based on an 8 MeV, CW 3 mA proton accelerator. In this paper, we present a beam-shaping assembly for this proton accelerator with such low 24 kW beam power, using composite moderator materials composed of five elements: Mg, Al, F, O, and Li. The calculation result of FLUKA with ENDF/B and JENDL libraries shows that the epithermal neutron beam flux is 1.57×109n/cm2/s with the CW 3 mA proton beam. The fast neutron component and the gamma ray component under free-air condition are 1.49×10-13Gy∙cm2 and 8.12×10-14Gy∙cm2 respectively, in line with IAEA-TECDOC-1223 design recommendations. The thermal analysis shows that the maximum temperature of beryllium target is 706.5 K, and the structure materials of BSA do not melt.

3.
Environ Int ; 192: 109015, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39312841

RESUMO

BACKGROUND: Cold environments pose serious threats on human health, with increased risk for myocardial infarction, stroke, frostbite, and hypothermia. Acquired cold acclimation is required to minimize cold-induced injures and to improve metabolic health. However, the underlying mechanisms remain to be fully elucidated. OBJECTIVE: We aimed to identify critical amino acids involved in cold acclimation and unmask the regulatory mechanisms. METHODS: A total of twenty male participants were recruited and followed up after 3 months' natural cold exposure. Cold-induced vasodilation (CIVD) tests and clinical biochemical analysis were performed at baseline and after 3-months cold exposure, whilst blood samples were collected, and plasma amino acids were analyzed by targeted metabolomics. To further confirm the effect of lysine on cold tolerance and explain the latent mechanism, mice were challenged with chronic cold exposure for 7 days with lysine supplement, then core and local surface temperature as well as thermogenesis activity were detected. RESULTS: Continuous cold exposure shortened the CIVD onset time and increased the average finger temperature. Levels of the plasma lysine and glycine were decreased in both humans and mice. Venn analysis from three datasets revealed that lysine was the only significantly changed plasma amino acid, which strongly correlated with the altered CIVD. Moreover, mice sustained a relatively higher core temperature and surface temperature in the back, tail and paws upon lysine supplementation. Furthermore, lysine supplementation increased the level of histone H3K18cr and promoted the gene and protein expression of Cpt1a, Cpt2 and Cyp27a1 in liver. CONCLUSION: Our work identified lysine as a critical amino acid for the remodeling of hepatic histone crotonylation that facilitates cold acclimation.

4.
Biochem Biophys Res Commun ; 733: 150623, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39255619

RESUMO

After prolonged space operations, astronauts showed maladaptive atrophy within mostly left-ventricular myocardium, resulting in cardiac dysfunction. However, the mechanism of cardiac dysfunction under microgravity conditions is unclear, and the relevant prevention and treatment measures also need to be explored. Through simulating the microgravity environment with a tail suspension (TS) model, we found that long-term exposure to microgravity promotes aging of mouse hearts, which is closely related to cardiac dysfunction. The intravenous administration of adipose-derived mesenchymal stem cells (ADSCs) emerged preventive and therapeutic effect against myocardial senescence and the decline in cardiac function. Plasma metabolomics analysis suggests the loss of NAD+ in TS mice and motivated myocardial NAD + metabolism and utilization in ADSCs-treated mice, likely accounting for ADSCs' function. Oral administration of nicotinamide mononucleotide (NMN, a NAD + precursor) showed similar therapeutic effect to ADSCs treatment. Collectively, these data implicate the effect of ADSCs in microgravity-induced cardiac dysfunction and provide new therapeutic ideas for aging-related maladaptive cardiac remodeling.

5.
mSystems ; : e0108924, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39345150

RESUMO

Bartonella grahamii is one of the most prevalent Bartonella species in wild rodents and has been associated with human cases of neuroretinitis. The structure and distribution of genomic diversity in natural B. grahamii is largely unexplored. Here, we have applied a comprehensive population genomic and phylogenomic analysis to 172 strains of B. grahamii to unravel the genetic differences and influencing factors that shape its populations. The findings reveal a remarkable genomic diversity within the species, primarily in the form of single- nucleotide polymorphisms. The open pangenome of B. grahamii indicates a dynamic genomic evolution influenced by its ecological niche. Whole-genome data allowed us to decompose B. grahamii diversity into six phylogroups, each characterized by a unique "mosaic pattern" of hosts and biogeographic regions. This suggests a complex interplay between host specificity and biogeography. In addition, our study suggests a possible origin of European strains from Asian lineages, and host factors have a more significant impact on the genetic differentiation of B. grahamii than geographical factors. These insights contribute to understanding the evolutionary history of this pathogen and provide a foundation for future epidemiological research and public health strategies. IMPORTANCE: Bartonella grahamii has been reported worldwide and shown to infect humans. Up to now, an effective transmission route of B. grahamii to humans has not been confirmed. The genetic evolution of B. grahamii and the relationship between B. grahamii and its host need to be further studied. The factors driving the genetic diversity of B. grahamii are still controversial. The results showed that the European isolates shared a common ancestor with the Chinese isolates. Host factors were shown to play an important role in driving the genetic diversity of B. grahamii. When host factors were fixed, geographic barriers drove B. grahamii microevolution. Our study emphasizes the importance of characterizing isolate genomes derived from hosts and geographical locations and provides a new reference for the origin of B. grahamii.

6.
PLoS One ; 19(9): e0310647, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39348392

RESUMO

BACKGROUND: Previous studies have yielded conflicting results regarding the link between maternal perinatal depression and asthma in children. To provide a clearer understanding of this relationship, a comprehensive meta-analysis was carried out to evaluate the association mentioned above. METHODS: A comprehensive review of observational studies was conducted by searching electronic databases including Medline, Embase, and Web of Science. The data were combined using a randomized-effects model taking into account potential variations. Subgroup analyses were performed to evaluate the possible impact of study characteristics on outcomes. RESULTS: Ten cohort studies, which included 833,230 mother-child pairs, were examined in the analysis. Maternal depressive symptoms during the perinatal period were associated with an increased risk of asthma in offspring (risk ratio [RR]: 1.24, 95% confidence interval [CI]: 1.19 to 1.30, p < 0.001; I2 = 0%). Further sensitivity analyses restricted to multivariate studies (RR: 1.24, 95% CI: 1.19 to 1.30, p < 0.001; I2 = 0%) or studies where asthma was diagnosed in children aged three years or older (RR: 1.24, 95% CI: 1.19 to 1.30, p < 0.001; I2 = 0%) revealed consistent outcomes. Subgroup analyses according to study design, methods for the diagnosis of maternal depression, timing for the evaluation of maternal depression, methods for the validation of asthma in offspring, adjustment of maternal smoking during pregnancy and of maternal asthma, or study quality score showed similar results (p for subgroup difference all > 0.05). CONCLUSIONS: Maternal perinatal depression appears to be significantly linked to a higher occurrence of childhood asthma in children.


Assuntos
Asma , Depressão , Humanos , Asma/epidemiologia , Feminino , Gravidez , Depressão/complicações , Criança , Fatores de Risco , Efeitos Tardios da Exposição Pré-Natal , Pré-Escolar , Mães/psicologia , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/psicologia
7.
Phytother Res ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39267167

RESUMO

Long-term inflammation can cause chronic pain and trigger patients' anxiety by sensitizing the central nervous system. However, effective drugs with few side effects for treating chronic pain-induced anxiety are still lacking. The anxiolytic and anti-inflammatory effects of ruscogenin (RUS), an important active compound in Ophiopogon japonicus, were evaluated in a mouse model of chronic inflammatory pain and N9 cells. RUS (5, 10, or 20 mg/kg/day, i.g.) was administered once daily for 7 days after CFA injection; pain- and anxiety-like behaviors were assessed in mice. Anti-inflammatory effect of RUS (0.1, 1, 10 µM) on N9 microglia after LPS treatment was evaluated. Inflammatory markers (TNF-α, IL-1ß, IL-6, CD86, IL-4, ARG-1, and CD206) were measured using qPCR. The levels of IBA1, ROS, NF-κB, TLR4, P-IKK, P-IκBα, and P65, MAPKs (ERK, JNK, and P38), NLRP3 (caspase-1, ASC, and NLRP3) were detected by Western blotting or immunofluorescence staining. The potential target of RUS was validated by molecular docking and adeno-associated virus injection. Mice in CFA group exhibited allodynia and anxiety-like behaviors. LPS induced neuroinflammation in N9 cells. Both CFA and LPS increased the levels of IBA1, ROS, and inflammatory markers. RUS (10 mg/kg in vivo and 1 µM in vitro) alleviated these alterations through NF-κB/MAPKs/NLRP3 signaling pathways but had no effect on pain hypersensitivity. TLR4 strongly interacted with RUS, and TLR4 overexpression abolished the effects of RUS on anxiety and neuroinflammation. RUS exerts anti-inflammatory and anxiolytic effects via TLR4-mediated NF-κB/MAPKs/NLRP3 signaling pathways, which provides a basis for the treatment of chronic pain-induced anxiety.

8.
J Am Chem Soc ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39293040

RESUMO

A Pd-catalyzed asymmetric higher-order dipolar cycloaddition between allenyl carbonates and azadienes is achieved by exploiting novel alkylidene-π-allyl-Pd dipoles. This research provides a modular platform for the synthesis of challenging chiral endocyclic allenes bearing a medium-sized heterocyclic motif and a centrally chiral stereocenter in good yields with high enantio- and diastereoselectivities (29 examples, up to 97% yield, 97:3 er and >19:1 dr). Experimental and computational studies elucidate the possible reaction mechanism and the observed stereochemical results. Based on the mechanistic understanding, a new π-propargyl-Pd dipole was designed to further extend the success of the higher order dipolar cycloaddition strategy to the synthesis of 10-membered endocyclic alkynes from propargyl carbonates and azadienes (13 examples, up to 98% yield and 94.5:5.5 er).

9.
Talanta ; 280: 126746, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39182415

RESUMO

Magnetic solid-phase extraction (MSPE) technology for tetracycline (TCC) was developed by employing the novel and pre-designed Fe3O4-COOH@hydrogen-bonded organic frameworks (HOFs) adsorbents in complex food samples. The HOF shell was grown onto the Fe3O4-COOH core by in-situ self-assembled method. The excellent MSPE performances with less solvent, less adsorbent and time consumption were derived from the hydrogen bonding, π-π and hydrophobic interactions between HOF shell and TCC. Combined with HPLC analysis, Fe3O4@ HOFs adsorbent reduced matrix effects and the established MSPE-HPLC method for TCC gave the linearity of 0.001-6 µg mL-1 with the limit of detection 0.0003 µg mL-1. The recoveries in pure milk, canned yellow peach and carrot were 82.4-103.7 %. The method provided a simple, efficient and dependable alternative to monitor trace TCC antibiotics in food or environmental samples.


Assuntos
Contaminação de Alimentos , Estruturas Metalorgânicas , Extração em Fase Sólida , Tetraciclina , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Tetraciclina/análise , Tetraciclina/isolamento & purificação , Tetraciclina/química , Estruturas Metalorgânicas/química , Contaminação de Alimentos/análise , Ligação de Hidrogênio , Leite/química , Adsorção , Limite de Detecção , Antibacterianos/análise , Antibacterianos/química , Antibacterianos/isolamento & purificação , Análise de Alimentos/métodos , Fenômenos Magnéticos , Animais , Óxido Ferroso-Férrico/química , Daucus carota/química
10.
JMIR Public Health Surveill ; 10: e55822, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39140274

RESUMO

Background: Studies have reported the adverse effects of cold events on influenza. However, the role of critical factors, such as characteristics of cold spells, and regional variations remain unresolved. Objective: We aimed to systematically evaluate the association between cold spells and influenza incidence in mainland China. Methods: This time series analysis used surveillance data of daily influenza from 325 sites in China in the 2014-2019 period. A total of 15 definitions of cold spells were adopted based on combinations of temperature thresholds and days of duration. A distributed lag linear model was used to estimate the short-term effects of cold spells on influenza incidence during the cool seasons (November to March), and we further explored the potential impact of cold spell characteristics (ie, intensity, duration, and timing during the season) on the estimated associations. Meta-regressions were used to evaluate the modification effect of city-level socioeconomic indicators. Results: The overall effect of cold spells on influenza incidence increased with the temperature threshold used to define cold spells, whereas the added effects were generally small and not statistically significant. The relative risk of influenza-associated with cold spells was 3.35 (95% CI 2.89-3.88), and the estimated effects were stronger during the middle period of cool seasons. The health effects of cold spells varied geographically and residents in Jiangnan region were vulnerable groups (relative risk 7.36, 95% CI 5.44-9.95). The overall effects of cold spells were positively correlated with the urban population density, population size, gross domestic product per capita, and urbanization rate, indicating a sterner response to cold spells in metropolises. Conclusions: Cold spells create a substantial health burden on seasonal influenza in China. Findings on regional and socioeconomic differences in the health effects of cold spells on seasonal influenza may be useful in formulating region-specific public health policies to address the hazardous effects of cold spells.


Assuntos
Temperatura Baixa , Influenza Humana , Humanos , China/epidemiologia , Influenza Humana/epidemiologia , Temperatura Baixa/efeitos adversos , Incidência , Estações do Ano
11.
Sci Bull (Beijing) ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39183108

RESUMO

Morpholines are widespread in many biologically and catalytically active agents, thus being an important aim of pharmaceutical and synthetic chemists. However, efficient strategies for the catalytic asymmetric synthesis of chiral morpholines bearing crowded stereogenic centers still remain elusive. Herein, we disclose a Cu-catalyzed asymmetric propargylic amination/desymmetrization strategy to help resolve this challenge. As a result, two kinds of structurally various chiral morpholines bearing rich functional groups and N-α-quaternary stereocenters were produced with high efficiency and selectivity (42 examples, up to 91 % yield, 97:3 er and > 19:1 dr). In addition, a series of transformations were performed to demonstrate the synthetic utility of this methodology. In particular, a hit compound for new antitumor drugs was identified through cellular evaluation. Furthermore, mechanistic investigations reveal that, hydrogen bonding in the key copper-allenylidene intermediate together with π-π stacking aids remote enantioinduction.

12.
Res Sq ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39149481

RESUMO

Cross-individual variability is considered the essence of biology, preventing precise mathematical descriptions of biological motion1-7 like the physics law of motion. Here we report that the cerebellum shapes motor kinematics by encoding dynamic motor frequencies with remarkable numerical precision and cross-individual uniformity. Using in-vivo electrophysiology and optogenetics in mice, we confirmed that deep cerebellar neurons encoded frequencies via populational tuning of neuronal firing probabilities, creating cerebellar oscillations and motions with matched frequencies. The mechanism was consistently presented in self-generated rhythmic and non-rhythmic motions triggered by a vibrational platform, or skilled tongue movements of licking in all tested mice with cross-individual uniformity. The precision and uniformity allowed us to engineer complex motor kinematics with designed frequencies. We further validated the frequency-coding function of the human cerebellum using cerebellar electroencephalography recordings and alternating-current stimulation during voluntary tapping tasks. Our findings reveal a cerebellar algorithm for motor kinematics with precision and uniformity, the mathematical foundation for brain-computer interface for motor control.

13.
Angew Chem Int Ed Engl ; : e202408426, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39177728

RESUMO

Isodesmic reactions, in which chemical bonds are redistributed between substrates and products, provide a general and powerful strategy for both biological and chemical synthesis. However, most isodesmic reactions involve either metathesis or functional-group transfer. Here, we serendipitously discovered a novel isodesmic reaction of indoles and anilines that proceeds intramolecularly under weakly acidic conditions. In this process, the five-membered ring of the indole motif is broken and a new indole motif is constructed on the aniline side, accompanied by the formation of a new aniline motif. Mechanistic studies revealed the pivotal role of σ→π* hyperconjugation on the nitrogen atom of the indole motif in driving this unusual isodesmic reaction. Furthermore, we successfully synthesized a diverse series of polycyclic indole derivatives; among quinolines, potential antitumor agents were identified using cellular and in vivo experiments, thereby demonstrating the synthetic utility of the developed methodology.

14.
Sci Adv ; 10(34): eadp2877, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39178268

RESUMO

Quantum communication networks are crucial for both secure communication and cryptographic networked tasks. Building quantum communication networks in a scalable and cost-effective way is essential for their widespread adoption. Here, we establish a complete polarization entanglement-based fully connected network, which features an ultrabright integrated Bragg reflection waveguide quantum source, managed by an untrusted service provider, and a streamlined polarization analysis module, which requires only one single-photon detector for each user. We perform a continuously working quantum entanglement distribution and create correlated bit strings between users. Within the framework of one-time universal hashing, we provide the experimental implementation of source-independent quantum digital signatures using imperfect keys circumventing the necessity for private amplification. We further beat the 1/3 fault tolerance bound in the Byzantine agreement, achieving unconditional security without relying on sophisticated techniques. Our results offer an affordable and practical route for addressing consensus challenges within the emerging quantum network landscape.

15.
Biosens Bioelectron ; 264: 116672, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39151263

RESUMO

Low accuracy of diagnosing prostate cancer (PCa) was easily caused by only assaying single prostate specific antigen (PSA) biomarker. Although conventional reported methods for simultaneous detection of two specific PCa biomarkers could improve the diagnostic efficiency and accuracy, low detection sensitivity restrained their use in extreme early-stage PCa clinical assay applications. In order to overcome above drawbacks, this paper herein proposed a multiplexed dual optical microfibers separately functionalized with gold nanorods (GNRs) and Au nanobipyramids (Au NBPs) nanointerfaces with strong localized surface plasmon resonance (LSPR) effects. The sensors could simultaneously detect PSA protein biomarker and long noncoding RNA prostate cancer antigen 3 (lncRNA PCA3) with ultrahigh sensitivity and remarkable specificity. Consequently, the proposed dual optical microfibers multiplexed biosensors could detect the PSA protein and lncRNA PCA3 with ultra-low limit-of-detections (LODs) of 3.97 × 10-15 mol/L and 1.56 × 10-14 mol/L in pure phosphorus buffer solution (PBS), respectively, in which the obtained LODs were three orders of magnitude lower than existed state-of-the-art PCa assay technologies. Additionally, the sensors could discriminate target components from complicated physiological environment, that showing noticeable biosensing specificity of the sensors. With good performances of the sensors, they could successfully assay PSA and lncRNA PCA3 in undiluted human serum and urine simultaneously, respectively. Consequently, our proposed multiplexed sensors could real-time high-sensitivity simultaneously detect complicated human samples, that providing a novel valuable approach for the high-accurate diagnosis of early-stage PCa individuals.


Assuntos
Antígenos de Neoplasias , Técnicas Biossensoriais , Ouro , Limite de Detecção , Nanotubos , Antígeno Prostático Específico , Neoplasias da Próstata , RNA Longo não Codificante , Ressonância de Plasmônio de Superfície , Humanos , Antígeno Prostático Específico/sangue , Masculino , Ouro/química , RNA Longo não Codificante/genética , RNA Longo não Codificante/sangue , RNA Longo não Codificante/urina , Antígenos de Neoplasias/urina , Antígenos de Neoplasias/sangue , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/sangue , Neoplasias da Próstata/urina , Nanotubos/química , Nanopartículas Metálicas/química , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/urina
16.
Opt Lett ; 49(15): 4182-4185, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090889

RESUMO

Replica symmetry breaking (RSB) has been introduced in a random laser to investigate the interactions between disorder and fluctuations. In this work, the dynamic difference between four non-energy transfer and Förster resonance energy transfer (FRET)-assisted random laser systems is investigated based on RSB. It is found that FRET is one of the key factors influencing RSB, and it is demonstrated that RSB in a random laser is not robust. This dynamic difference can be attributed to the different disorders induced by the gain mechanism in different random laser systems. This provides experimental evidence and theoretical support for the classification feasibility of RL with different emission mechanisms employing RSB.

17.
J Am Chem Soc ; 146(28): 18892-18898, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38968086

RESUMO

Herein, we designed a reaction for the desymmetrization-addition of cyclopropenes to imines by leveraging the synergy between photoredox and asymmetric cobalt catalysis. This protocol facilitated the synthesis of a series of chiral functionalized cyclopropanes with high yield, enantioselectivity, and diastereoselectivity (44 examples, up to 93% yield and >99% ee). A possible reaction mechanism involving cyclopropene desymmetrization by Co-H species and imine addition by Co-alkyl species was proposed. This study provides a novel route to important chiral cyclopropanes and extends the frontier of asymmetric metallaphotoredox catalysis.

18.
New Phytol ; 243(5): 2021-2036, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39014531

RESUMO

Phytohormones possess unique chemical structures, and their physiological effects are regulated through intricate interactions or crosstalk among multiple phytohormones. MALDI-MSI enables the simultaneous detection and imaging of multiple hormones. However, its application for tracing phytohormones is currently restricted by low abundance of hormone in plant and suboptimal matrix selection. 2,4-Dihydroxy-5-nitrobenzoic acid (DHNBA) was reported as a new MALDI matrix for the enhanced detection and imaging of multiple phytohormones in plant tissues. DHNBA demonstrates remarkable sensitivity improvement when compared to the commonly used matrix, 2,5-dihydroxybenzoic acid (DHB), in the detection of isoprenoid cytokinins (trans-zeatin (tZ), dihy-drozeatin (DHZ), meta-topolin (mT), and N6-(Δ2-isopentenyl) adenine (iP)), jasmonic acid (JA), abscisic acid (ABA), and 1-aminocyclo-propane-1-carboxylic acid (ACC) standards. The distinctive properties of DHNBA (i.e. robust UV absorption, uniform matrix deposition, negligible background interference, and high ionization efficiency of phytohormones) make it as an ideal matrix for enhanced detection and imaging of phytohormones, including tZ, DHZ, ABA, indole-3-acetic acid (IAA), and ACC, by MALDI-MSI in various plant tissues, for example germinating seeds, primary/lateral roots, and nodules. Employing DHNBA significantly enhances our capability to concurrently track complex phytohormone biosynthesis pathways while providing precise differentiation of the specific roles played by individual phytohormones within the same category. This will propel forward the comprehensive exploration of phytohormonal functions in plant science.


Assuntos
Reguladores de Crescimento de Plantas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Gentisatos/metabolismo , Gentisatos/química
19.
J Chromatogr A ; 1731: 465180, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39053255

RESUMO

Novel magnetic covalent organic frameworks (COFs) were prepared by one-pot synthetic strategy and employed as an efficient adsorbent for magnetic solid-phase extraction (MSPE) of naphthaleneacetic acid (NAA) in food samples. Depending on the predesigned the hydrogen bonding, π-π and hydrophobic interactions of magnetic COFs, the efficient and selective extraction process for NAA was achieved within 15 min. The magnetic COFs adsorbent combined with HPLC-UV was devoted to develop a novel quantitative method for NAA in complex food. The method afforded good coefficient in range of 0.002-10.0 µg mL-1 and low limit of detection was 0.0006 µg mL-1. And the newly established method afforded less adsorbent consumption, wider linearity and lower LODs than the reported analytical methods. Ultimately, the method was successfully applied to determine NAA in fresh pear, tomato and peach juice. The magnetic COFs based MSPE coupled with HPLC-UV method provided a simple, efficient and dependable alternative to monitor trace NAA in food samples.


Assuntos
Limite de Detecção , Estruturas Metalorgânicas , Ácidos Naftalenoacéticos , Extração em Fase Sólida , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Naftalenoacéticos/análise , Ácidos Naftalenoacéticos/química , Estruturas Metalorgânicas/química , Adsorção , Contaminação de Alimentos/análise , Solanum lycopersicum/química , Sucos de Frutas e Vegetais/análise
20.
Mol Cell ; 84(15): 2984-3000.e8, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39002544

RESUMO

5-methylcytosine (m5C) is a prevalent RNA modification crucial for gene expression regulation. However, accurate and sensitive m5C sites identification remains challenging due to severe RNA degradation and reduced sequence complexity during bisulfite sequencing (BS-seq). Here, we report m5C-TAC-seq, a bisulfite-free approach combining TET-assisted m5C-to-f5C oxidation with selective chemical labeling, therefore enabling direct base-resolution m5C detection through pre-enrichment and C-to-T transitions at m5C sites. With m5C-TAC-seq, we comprehensively profiled the m5C methylomes in human and mouse cells, identifying a substantially larger number of confident m5C sites. Through perturbing potential m5C methyltransferases, we deciphered the responsible enzymes for most m5C sites, including the characterization of NSUN5's involvement in mRNA m5C deposition. Additionally, we characterized m5C dynamics during mESC differentiation. Notably, the mild reaction conditions and preservation of nucleotide composition in m5C-TAC-seq allow m5C detection in chromatin-associated RNAs. The accurate and robust m5C-TAC-seq will advance research into m5C methylation functional investigation.


Assuntos
5-Metilcitosina , Sulfitos , Transcriptoma , 5-Metilcitosina/metabolismo , 5-Metilcitosina/química , Animais , Humanos , Camundongos , Sulfitos/química , Metiltransferases/metabolismo , Metiltransferases/genética , Perfilação da Expressão Gênica/métodos , Diferenciação Celular
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