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1.
Sci Total Environ ; 953: 176168, 2024 Nov 25.
Article in English | MEDLINE | ID: mdl-39260501

ABSTRACT

Hexabromocyclododecane (HBCD)-containing waste was co-disposed in a cement kiln to evaluate its destruction removal efficiency (DRE) and its impact on polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) formation. The DRE of HBCD exceeded 99.9999 %. The residual HBCD after disposal was mainly found in kiln head ash and clinker. Stack gas at kiln head and tail exhibited average PBDD/Fs emission levels (sum of 13 2,3,7,8-PBDD/Fs congeners) of 0.36 and 0.42 ng m-3, respectively, with octa-BDD predominating. However, in the kiln tail ash, hexaBDF and hepta-BDF were secondarily generated, leading to an increase in PBDFs concentration. Notably, most HBCD underwent debromination and ring-opening in the calciner, with released bromine absorbed and removed by CaO. Its decomposition products such as polycyclic aromatic hydrocarbons, biphenyls and their derivatives served as carbon sources for PBDD/Fs synthesis. However, co-disposal of HBCD did not significantly raise PBDD/Fs emissions but altered their homolog distribution from PBDDs to PBDFs. Emission factors of HBCD and PBDD/Fs were the highest in the clinker at 6.55 × 102 and 0.55 × 102 µg t-1, respectively. Therefore, attention was needed for the potential secondary release of pollutants during the transportation and utilization of clinker. These findings enhanced understanding of the distribution and formation pathways of PBDD/Fs during cement kiln co-processing, providing insights for their source control.

2.
iScience ; 27(9): 110858, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39310754

ABSTRACT

The development of efficient catalysts for ammonia synthesis under mild conditions is critical for establishing a carbon-neutral society powered by renewable ammonia. While significant effort has been focused on Fe and Ru-based catalysts, there have been very limited studies on manganese-based catalysts for ammonia synthesis because of their low intrinsic catalytic activity. Herein, we report that the synergy between manganese nitride (Mn4N) and europium nitride (EuN) yields an ammonia synthesis rate that is 41 and 25 times higher than that of neat Mn4N and EuN, respectively. Detailed studies suggest that a [Eu-N-Mn] species at the interface of Mn4N and EuN plays a pivotal role in ammonia synthesis. Compositing of Mn4N with other rare earth metal nitrides such as LaN, PrN, and CeN also leads to a significant enhancement in catalytic activity. This work broadens the scope of advanced nitride catalysts for ammonia synthesis.

3.
Mikrochim Acta ; 191(10): 622, 2024 09 25.
Article in English | MEDLINE | ID: mdl-39320530

ABSTRACT

A novel electrochemiluminescence (ECL) method was developed for determination of protein kinase A (PKA) ultra-sensitively based on amidated nano-titanium (NH2-TiO2) embellished carbon dots (Mg@N-CDs) fluorescent probe, which integrated the target recognition and ECL signal enhancement. The Cys-labeled kemptides were employed to build a serine-rich synthetic substrate-heptapeptide (Cys-kemptide) on the Au-electrode surface. Then, the PKA-induced biosensor was triggered as a signal switch to introduce the large amounts of TiO2 decorated Mg@N-CD nanohybrid (Ti@NMg-CDs) into AuE/Cys-phosphopeptides for signal output. In particular, the presence of PKA could induce the formation of Cys-phosphopeptides by the catalytic reaction between specific substrate (kemptide) and PKA, which acts as an initiator to link the Ti@NMg-CDs according to the bridge interactions Ti-O-P. In this way, multiple Cys-phosphopeptides were adsorbed onto a single Ti@NMg-CDs, and the Ti@NMg-CDs not only provided high specific selectivity but also large surface area, as well as unprecedented high ECL efficiency. Using this PKA-induced enhanced sensor, the limit of detection of the PKA was 4.89 × 10-4 U/mL (S/N = 3). The proposed ECL biosensor was also universally applicable for the screening of PKA inhibitors and determining of other kinases activity. Our sensing system has excellent performance of specificity and the screening of kinase inhibitors, as well as it will inspire future effort in clinical diagnostics and new drug discovery.


Subject(s)
Biosensing Techniques , Carbon , Cyclic AMP-Dependent Protein Kinases , Electrochemical Techniques , Luminescent Measurements , Phosphopeptides , Quantum Dots , Titanium , Titanium/chemistry , Biosensing Techniques/methods , Carbon/chemistry , Cyclic AMP-Dependent Protein Kinases/metabolism , Cyclic AMP-Dependent Protein Kinases/analysis , Quantum Dots/chemistry , Phosphopeptides/analysis , Electrochemical Techniques/methods , Luminescent Measurements/methods , Humans , Limit of Detection , Fluorescent Dyes/chemistry
4.
Mol Cell ; 84(18): 3513-3529.e5, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39255795

ABSTRACT

Innate immunity serves as the primary defense against viral and microbial infections in humans. The precise influence of cellular metabolites, especially fatty acids, on antiviral innate immunity remains largely elusive. Here, through screening a metabolite library, palmitic acid (PA) has been identified as a key modulator of antiviral infections in human cells. Mechanistically, PA induces mitochondrial antiviral signaling protein (MAVS) palmitoylation, aggregation, and subsequent activation, thereby enhancing the innate immune response. The palmitoyl-transferase ZDHHC24 catalyzes MAVS palmitoylation, thereby boosting the TBK1-IRF3-interferon (IFN) pathway, particularly under conditions of PA stimulation or high-fat-diet-fed mouse models, leading to antiviral immune responses. Additionally, APT2 de-palmitoylates MAVS, thus inhibiting antiviral signaling, suggesting that its inhibitors, such as ML349, effectively reverse MAVS activation in response to antiviral infections. These findings underscore the critical role of PA in regulating antiviral innate immunity through MAVS palmitoylation and provide strategies for enhancing PA intake or targeting APT2 for combating viral infections.


Subject(s)
Acyltransferases , Adaptor Proteins, Signal Transducing , Immunity, Innate , Interferon Regulatory Factor-3 , Lipoylation , Palmitic Acid , Signal Transduction , Immunity, Innate/drug effects , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/immunology , Humans , Animals , Palmitic Acid/pharmacology , Mice , HEK293 Cells , Interferon Regulatory Factor-3/metabolism , Interferon Regulatory Factor-3/genetics , Interferon Regulatory Factor-3/immunology , Acyltransferases/genetics , Acyltransferases/immunology , Acyltransferases/metabolism , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Mice, Inbred C57BL , Antiviral Agents/pharmacology , Neoplasm Proteins , Intracellular Signaling Peptides and Proteins
5.
Chem Commun (Camb) ; 60(77): 10760-10763, 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39248440

ABSTRACT

The chemical behaviors of alkali and alkaline earth metal hydrides including LiH, KH, MgH2, CaH2, and BaH2 under nitrogen plasma differ significantly from one another, exhibiting an ammonia production trend that contrasts with that observed under thermal conditions. A prominent feature of KH is its ability to facilitate plasma-assisted N2 fixation without generating H2 byproduct, showing high atomic economy in utilization of hydride ions for N2 reduction.

6.
J Gastroenterol ; 2024 Sep 21.
Article in English | MEDLINE | ID: mdl-39305336

ABSTRACT

BACKGROUND: Intestinal fibrosis is one of the most frequent and severe complications of Crohn's disease. Accumulating studies have reported that adipose mesenchymal stem cell-derived small extracellular vesicles (AMSC-sEVs) could alleviate renal fibrosis, hepatic fibrosis, etc., while their potential for treating intestinal fibrosis remains uncertain. Therefore, this study aims to determine the therapeutic effects of AMSC-sEVs on intestinal fibrosis and identify the mechanisms underlying these effects. METHODS: AMSC-sEVs were characterized using transmission electron microscopy, nanoparticle tracking analysis, and western blot. Whether AMSC-sEVs exert antifibrotic effects was investigated in two different murine models of intestinal fibrosis. Besides, AMSC-sEVs were co-cultured with primary human fibroblasts and CCD18co during transforming growth factor (TGF)-ß1 stimulation. Label-free proteomics and rescue experiments were performed to identify candidate molecules in AMSC-sEVs. Transcriptome sequencing revealed changes in mRNA levels among different groups. Lastly, proteins related to relevant signaling pathways were identified by western blotting, and their expression and activation status were assessed. RESULTS: AMSC-sEVs positively expressed CD63 and Alix and presented a classical "rim of a cup" and granule shape with approximately 43-100 nm diameter. AMSCs significantly alleviated intestinal fibrosis through secreted sEVs in vitro and in vivo. The milk fat globule-EGF factor 8 (MFGE8) was stably enriched in AMSC-sEVs and was an active compound contributing to the treatment of intestinal fibrosis by AMSCs. Mechanistically, AMSC-sEV-based therapies attenuated intestinal fibrosis by inhibiting the FAK/Akt signaling pathway. CONCLUSIONS: MFGE8-containing AMSC-sEVs attenuate intestinal fibrosis, partly through FAK/Akt pathway inhibition.

7.
Nat Chem Biol ; 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39103634

ABSTRACT

Liver fibrosis is an urgent clinical problem without effective therapies. Here we conducted a high-content screening on a natural Euphorbiaceae diterpenoid library to identify a potent anti-liver fibrosis lead, 12-deoxyphorbol 13-palmitate (DP). Leveraging a photo-affinity labeling approach, apolipoprotein L2 (APOL2), an endoplasmic reticulum (ER)-rich protein, was identified as the direct target of DP. Mechanistically, APOL2 is induced in activated hepatic stellate cells upon transforming growth factor-ß1 (TGF-ß1) stimulation, which then binds to sarcoplasmic/ER calcium ATPase 2 (SERCA2) to trigger ER stress and elevate its downstream protein kinase R-like ER kinase (PERK)-hairy and enhancer of split 1 (HES1) axis, ultimately promoting liver fibrosis. As a result, targeting APOL2 by DP or ablation of APOL2 significantly impairs APOL2-SERCA2-PERK-HES1 signaling and mitigates fibrosis progression. Our findings not only define APOL2 as a novel therapeutic target for liver fibrosis but also highlight DP as a promising lead for treatment of this symptom.

8.
JCI Insight ; 9(18)2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39163137

ABSTRACT

Palatine tonsils are the only air-contacted lymphoid organs that constantly engage in crosstalk with commensal microorganisms and serve as the first handling sites against microbial antigens. While tonsil inflammations have been implicated in various autoimmune diseases, including rheumatoid arthritis (RA), the precise role of tonsillar microbiota in autoimmune pathogenesis remains inadequately characterized. In this study, we profiled the tonsillar microbiota and identified a notable dysbiosis in patients with RA, particularly within the Streptococcus genus. Specifically, patients with RA exhibited an enrichment of pathogenic Streptococcus species, including S. pyogenes, S. dysgalactiae, and S. agalactiae. Colonization with these bacteria significantly exacerbated arthritis severity and increased autoimmune responses in collagen-induced arthritis (CIA). Furthermore, immunization with peptides derived from these pathogenic Streptococcus species directly induced experimental arthritis. Conversely, patients with RA demonstrated a marked deficiency in commensal Streptococcus members, notably S. salivarius. Treatment of CIA mice with S. salivarius attenuated the progression of arthritis and downregulated autoimmune responses. These findings highlight a pathogenic link of tonsillar microbiota with RA, shedding light on their contribution to autoimmunity.


Subject(s)
Arthritis, Experimental , Arthritis, Rheumatoid , Microbiota , Palatine Tonsil , Streptococcus , Arthritis, Rheumatoid/immunology , Arthritis, Rheumatoid/microbiology , Animals , Palatine Tonsil/microbiology , Palatine Tonsil/immunology , Humans , Mice , Arthritis, Experimental/immunology , Arthritis, Experimental/microbiology , Microbiota/immunology , Streptococcus/immunology , Male , Female , Dysbiosis/immunology , Dysbiosis/microbiology , Autoimmunity/immunology , Middle Aged , Mice, Inbred DBA
9.
Nat Commun ; 15(1): 7189, 2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39168976

ABSTRACT

Biological ion channels usually conduct the high-flux transport of 107 ~ 108 ions·s-1; however, the underlying mechanism is still lacking. Here, by applying the KcsA potassium channel as a typical example, and performing multitimescale molecular dynamics simulations, we demonstrate that there is coherence of the K+ ions confined in biological channels, which determines transport. The coherent oscillation state of confined K+ ions with a nanosecond-level lifetime in the channel dominates each transport event, serving as the physical basis for the high flux of ~108 ions∙s-1. The coherent transfer of confined K+ ions only takes several picoseconds and has no perturbation effect on the ion coherence, acting as the directional key of transport. Such ion coherence is allowed by quantum mechanics. An increase in the coherence can significantly enhance the ion conductance. These findings provide a potential explanation from the perspective of coherence for the high-flux ion transport with ultralow energy consumption of biological channels.


Subject(s)
Ion Transport , Molecular Dynamics Simulation , Potassium Channels , Potassium , Quantum Theory , Potassium Channels/metabolism , Potassium Channels/chemistry , Potassium/metabolism , Potassium/chemistry , Bacterial Proteins/metabolism , Bacterial Proteins/chemistry , Ions/metabolism
10.
Nat Commun ; 15(1): 6215, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39043664

ABSTRACT

Integrating genomics and histology for cancer prognosis demonstrates promise. Here, we develop a multi-classifier system integrating a lncRNA-based classifier, a deep learning whole-slide-image-based classifier, and a clinicopathological classifier to accurately predict post-surgery localized (stage I-III) papillary renal cell carcinoma (pRCC) recurrence. The multi-classifier system demonstrates significantly higher predictive accuracy for recurrence-free survival (RFS) compared to the three single classifiers alone in the training set and in both validation sets (C-index 0.831-0.858 vs. 0.642-0.777, p < 0.05). The RFS in our multi-classifier-defined high-risk stage I/II and grade 1/2 groups is significantly worse than in the low-risk stage III and grade 3/4 groups (p < 0.05). Our multi-classifier system is a practical and reliable predictor for recurrence of localized pRCC after surgery that can be used with the current staging system to more accurately predict disease course and inform strategies for individualized adjuvant therapy.


Subject(s)
Carcinoma, Renal Cell , Kidney Neoplasms , Neoplasm Recurrence, Local , Humans , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/pathology , Kidney Neoplasms/genetics , Kidney Neoplasms/pathology , Kidney Neoplasms/surgery , Male , Female , Neoplasm Recurrence, Local/genetics , Middle Aged , Aged , Prognosis , Genomics/methods , Adult , Neoplasm Staging , Deep Learning , Disease-Free Survival
11.
Int Immunopharmacol ; 139: 112693, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39024752

ABSTRACT

BACKGROUND: The therapeutic potential of adipose-derived mesenchymal stromal cells (AMSCs) in the treatment of intestinal fibrosis occured in patients with Crohn's disease (CD) remains unclear. Tumor necrosis factor-stimulated gene 6 (TSG6) protein plays a critical role in inflammation regulation and tissue repair. This study aimed to determine if AMSCs attenuate intestinal fibrosis by secreting paracrine TSG6 protein and explore the underlying mechanisms. METHODS: Two murine models for intestinal fibrosis were established using 2,4,6-trinitrobenzene sulfonic acid in BALB/c mice and dextran sulfate sodium in C57BL/6 mice. Primary human fibroblasts and CCD-18co cells were incubated with transforming growth factor (TGF)-ß1 to build two fibrosis cell models in vitro. RESULTS: Intraperitoneally administered AMSCs attenuated intestinal fibrosis in the two murine models, as evidenced by significant alleviation of colon shortening, collagen protein deposits, and submucosal thickening, and also decrease in the endoscopic and fibrosis scores (P < 0.001). Although intraperitoneally injected AMSCs did not migrate to the colon lesions, high levels of TSG6 expression and secretion were noticed both in vivo and in vitro. Similar to the role of AMSCs, injection of recombinant human TSG6 attenuated intestinal fibrosis in the mouse models, which was not observed with the administration of AMSCs with TSG6 knockdown or TSG6 neutralizing antibody. Mechanistically, TSG6 alleviates TGF-ß1-stimulated upregulation of α-smooth muscle actin (αSMA) and collagen I by inhibiting Smad2 phosphorylation. Furthermore, the expression of TSG6 is lower in intestinal fibrosis tissue of patients with Crohn's disease and can reduce pro-fibrotic protein (αSMA) secretion from primary ileal fibrotic tissue. CONCLUSIONS: AMSCs attenuate intestinal fibrosis by secreting paracrine TSG6 protein, which inhibits Smad2 phosphorylation. TSG6, a novel anti-fibrotic factor, could potentially improve intestinal fibrosis treatments.


Subject(s)
Cell Adhesion Molecules , Crohn Disease , Disease Models, Animal , Fibrosis , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Mice, Inbred BALB C , Mice, Inbred C57BL , Smad2 Protein , Animals , Humans , Mesenchymal Stem Cells/metabolism , Cell Adhesion Molecules/metabolism , Cell Adhesion Molecules/genetics , Crohn Disease/therapy , Crohn Disease/pathology , Crohn Disease/metabolism , Mice , Smad2 Protein/metabolism , Male , Dextran Sulfate , Trinitrobenzenesulfonic Acid , Adipose Tissue/metabolism , Transforming Growth Factor beta1/metabolism , Cells, Cultured , Female , Fibroblasts/metabolism , Colon/pathology , Colon/metabolism , Colitis/chemically induced , Colitis/therapy , Colitis/pathology
12.
Nat Commun ; 15(1): 4999, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38866834

ABSTRACT

Cryptophytes are ancestral photosynthetic organisms evolved from red algae through secondary endosymbiosis. They have developed alloxanthin-chlorophyll a/c2-binding proteins (ACPs) as light-harvesting complexes (LHCs). The distinctive properties of cryptophytes contribute to efficient oxygenic photosynthesis and underscore the evolutionary relationships of red-lineage plastids. Here we present the cryo-electron microscopy structure of the Photosystem II (PSII)-ACPII supercomplex from the cryptophyte Chroomonas placoidea. The structure includes a PSII dimer and twelve ACPII monomers forming four linear trimers. These trimers structurally resemble red algae LHCs and cryptophyte ACPI trimers that associate with Photosystem I (PSI), suggesting their close evolutionary links. We also determine a Chl a-binding subunit, Psb-γ, essential for stabilizing PSII-ACPII association. Furthermore, computational calculation provides insights into the excitation energy transfer pathways. Our study lays a solid structural foundation for understanding the light-energy capture and transfer in cryptophyte PSII-ACPII, evolutionary variations in PSII-LHCII, and the origin of red-lineage LHCIIs.


Subject(s)
Cryoelectron Microscopy , Cryptophyta , Light-Harvesting Protein Complexes , Photosystem II Protein Complex , Photosystem II Protein Complex/metabolism , Photosystem II Protein Complex/chemistry , Light-Harvesting Protein Complexes/metabolism , Light-Harvesting Protein Complexes/chemistry , Cryptophyta/metabolism , Photosynthesis , Models, Molecular , Energy Transfer , Photosystem I Protein Complex/metabolism , Photosystem I Protein Complex/chemistry , Chlorophyll A/metabolism , Chlorophyll A/chemistry
13.
J Phys Chem Lett ; 15(25): 6662-6667, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38889366

ABSTRACT

Lithium hydride (LiH), a saline hydride with a hydrogen density of 12.6 wt %, is highly thermostable, which hinders its extensive application in hydrogen storage. In this study, we demonstrate a distinct photodecomposition of LiH under ambient conditions. Ultraviolet-visible (UV-vis) illumination induces hydrogen release and creates surface hydrogen vacancies on LiH. The subsequent H- migration enables hydrogen desorption and the accumulation of vacancies at the subsurface, resulting in the generation of metallic Li clusters. Rehydrogenation, on the contrary, can be charged under UV-vis illumination in 1 bar H2. Such phenomena show that the thermodynamic and kinetic limits in the re/dehydrogenation of LiH can be broken under illumination, which allows hydrogen storage over the LiH surface at temperatures ∼600 K lower than those of the corresponding thermal process. This work provides new insights into the interaction of semiconducting hydrides and photons and opens an avenue for the development and optimization of materials for hydrogen storage and related photodriven reactions.

15.
ACS Appl Mater Interfaces ; 16(20): 26500-26511, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38739095

ABSTRACT

In this study, we propose and implement a deep neural network framework based on multitask learning aimed at simplifying the forward modeling and inverse design process of photonic devices integrating active metasurfaces. We demonstrate and validate our approach by constructing a continuously tunable bandpass filter that is effective in the midwave infrared region. The key to this filter is the combination of a metasurface and Fabry-Perot (F-P) cavity structure of the tunable phase-change material Ge2Sb2Se4Te (GSST) and the precise control of the crystallinity of the GSST by a silicon-based heater. With the help of a deep learning framework, we are able to independently model the crystallinity and geometric parameters of the filter to maximize the use of GSST tuning for bandpass filtering. Our model discusses the self-attention mechanism and the effect of noise and compares several existing popular algorithms, and the results show that a multitask deep learning strategy can better assist the on-demand reverse design of photonic structures with phase change materials. This opens up new possibilities for personalization and functional extension of optical devices.

16.
Front Cardiovasc Med ; 11: 1383567, 2024.
Article in English | MEDLINE | ID: mdl-38720919

ABSTRACT

Background: Patients with obstructive sleep apnea hypopnea syndrome (OSAHS) combined with resistant hypertension (RH) have a high risk of developing primary aldosteronism (PA). This study investigated the aldosterone-renin ratio (ARR), plasma aldosterone concentration (PAC), and plasma renin activity (PRA) to determine the optimal cutoff values for PA diagnosis in patients with OSAHS combined with RH. Methods: Patients diagnosed with moderate and severe OSAHS combined with RH were recruited from the inpatient clinic of the Department of Endocrinology at Ji'an Central Hospital between October 2020 and April 2023. The included patients were divided into PA and no-PA groups. Diagnostic accuracy measures were calculated for each group, and receiver operating characteristic (ROC) curves were generated. Results: A total of 241 patients were included, of which 103 had positive ARR screening results in the diagnostic accuracy analysis and 66 were diagnosed with PA. PAC and ARR showed moderate predictive capacity for PA, with area under the curve (AUC) values of 0.66 [95% confidence interval (CI): 0.55-0.77] and 0.72 (95% CI: 0.63-0.82), respectively, while PRA exhibited a limited predictive capacity (AUC = 0.51, 95% CI: 0.40-0.63). Using 45 as the optimal cutoff value for ARR, the sensitivity was 86% and the specificity was 52%. The optimal cutoff value for PAC was 17, with a sensitivity of 78% and a specificity of 55%. Notably, in patients with severe OSAHS, ARR at screening demonstrated significant predictive value for PA, with an AUC of 0.84 (95% CI: 0.72-0.96), a sensitivity of 85%, and a specificity of 76%. Conversely, in patients with moderate OSAHS, only ARR demonstrated significant predictive value for PA diagnosis, while PAC did not demonstrate notable diagnostic value. Conclusion: ARR and PAC are initial screening tools for PA, facilitating early detection, particularly in low-resource settings. In patients with OSAHS and RH, the ARR and PAC thresholds for PA diagnosis may require more stringent adjustment.

17.
Heliyon ; 10(9): e30791, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38765160

ABSTRACT

To investigate the dynamic changes in dry matter accumulation in maize after anthesis, we established a logistic model to describe grain filling characteristics (GFC), and analyzed differences between spring and summer maize, and the influence of meteorological factors. The results showed that the logistic model accurately simulated the dynamic changes in grain growth. For spring maize, the fitted hundred-grain weight at maturity was closely related to the average grain filling rate until maturity, days of the active grain filling period, time of the maximum grain filling rate, and duration of the rapid increase in grain weight. For summer maize, it was closely related to the time of the maximum grain filling rate, days of active grain filling period, duration of gradual grain weight, and the rapidly increasing period. The filling characteristics of spring and summer maize differed because of the different meteorological conditions and biological characteristics. The grain filling duration of spring maize was longer than that of summer maize. The maximum grain filling rate of spring maize occurred later than that of summer maize. Temperature and precipitation were the main meteorological factors affecting the hundred-grain weight of spring maize, whereas temperature was the main factor affecting summer maize. The response of spring maize GFC to meteorological factors was more complex than that of summer maize. These results are important for the development of appropriate strategies for improving maize productivity in China.

18.
Mol Biol Rep ; 51(1): 506, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38622341

ABSTRACT

BACKGROUND: Atrial Fibrillation (AF), a prevalent arrhythmic condition, is intricately associated with atrial fibrosis, a major pathological contributor. Central to the development of atrial fibrosis is myocardial inflammation. This study focuses on Atrial Natriuretic Peptide (ANP) and its role in mitigating atrial fibrosis, aiming to elucidate the specific mechanisms by which ANP exerts its effects, with an emphasis on fibroblast dynamics. METHODS AND RESULTS: The study involved forty Sprague-Dawley rats, divided into four groups: control, Angiotensin II (Ang II), Ang II + ANP, and ANP only. The administration of 1 µg/kg/min Ang II was given to Ang II and Ang II + ANP groups, while both Ang II + ANP and ANP groups received 0.1 µg/kg/min ANP intravenously for a duration of 14 days. Cardiac fibroblasts were used for in vitro validation of the proposed mechanisms. The study observed that rats in the Ang II and Ang II + ANP groups showed an increase in blood pressure and a decrease in body weight, more pronounced in the Ang II group. Diastolic dysfunction, a characteristic of the Ang II group, was alleviated by ANP. Additionally, ANP significantly reduced Ang II-induced atrial fibrosis, myofibroblast proliferation, collagen overexpression, macrophage infiltration, and the elevated expression of Interleukin 6 (IL-6) and Tenascin-C (TN-C). Transcriptomic sequencing indicated enhanced PI3K/Akt signaling in the Ang II group. Furthermore, in vitro studies showed that ANP, along with the PI3K inhibitor LY294002, effectively reduced PI3K/Akt pathway activation and the expression of TN-C, collagen-I, and collagen-III, which were induced by Ang II. CONCLUSIONS: The study demonstrates ANP's potential in inhibiting myocardial inflammation and reducing atrial fibrosis. Notably, ANP's effect in countering atrial fibrosis seems to be mediated through the suppression of the Ang II-induced PI3K/Akt-Tenascin-C signaling pathway. These insights enhance our understanding of AF pathogenesis and position ANP as a potential therapeutic agent for treating atrial fibrosis.


Subject(s)
Atrial Fibrillation , Atrial Natriuretic Factor , Rats , Animals , Rats, Sprague-Dawley , Atrial Natriuretic Factor/pharmacology , Atrial Natriuretic Factor/metabolism , Proto-Oncogene Proteins c-akt , Phosphatidylinositol 3-Kinases , Tenascin , Atrial Fibrillation/drug therapy , Angiotensin II/pharmacology , Inflammation/drug therapy , Collagen , Fibrosis
20.
Front Plant Sci ; 15: 1373081, 2024.
Article in English | MEDLINE | ID: mdl-38576786

ABSTRACT

The brown planthopper (BPH) is the most destructive insect pest that threatens rice production globally. Developing rice varieties incorporating BPH-resistant genes has proven to be an effective control measure against BPH. In this study, we assessed the resistance of a core collection consisting of 502 rice germplasms by evaluating resistance scores, weight gain rates and honeydew excretions. A total of 117 rice varieties (23.31%) exhibited resistance to BPH. Genome-wide association studies (GWAS) were performed on both the entire panel of 502 rice varieties and its subspecies, and 6 loci were significantly associated with resistance scores (P value < 1.0e-8). Within these loci, we identified eight candidate genes encoding receptor-like protein kinase (RLK), nucleotide-binding and leucine-rich repeat (NB-LRR), or LRR proteins. Two loci had not been detected in previous study and were entirely novel. Furthermore, we evaluated the predictive ability of genomic selection for resistance to BPH. The results revealed that the highest prediction accuracy for BPH resistance reached 0.633. As expected, the prediction accuracy increased progressively with an increasing number of SNPs, and a total of 6.7K SNPs displayed comparable accuracy to 268K SNPs. Among various statistical models tested, the random forest model exhibited superior predictive accuracy. Moreover, increasing the size of training population improved prediction accuracy; however, there was no significant difference in prediction accuracy between a training population size of 737 and 1179. Additionally, when there existed close genetic relatedness between the training and validation populations, higher prediction accuracies were observed compared to scenarios when they were genetically distant. These findings provide valuable resistance candidate genes and germplasm resources and are crucial for the application of genomic selection for breeding durable BPH-resistant rice varieties.

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