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1.
Nature ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143208

RESUMEN

Hot-carrier transistors are a class of devices that leverage the excess kinetic energy of carriers. Unlike regular transistors, which rely on steady-state carrier transport, hot-carrier transistors modulate carriers to high-energy states, resulting in enhanced device speed and functionality. These characteristics are essential for applications that demand rapid switching and high-frequency operations, such as advanced telecommunications and cutting-edge computing technologies1-5. However, the traditional mechanisms of hot-carrier generation are either carrier injection6-11 or acceleration12,13, which limit device performance in terms of power consumption and negative differential resistance14-17. Mixed-dimensional devices, which combine bulk and low-dimensional materials, can offer different mechanisms for hot-carrier generation by leveraging the diverse potential barriers formed by energy-band combinations18-21. Here we report a hot-emitter transistor based on double mixed-dimensional graphene/germanium Schottky junctions that uses stimulated emission of heated carriers to achieve a subthreshold swing lower than 1 millivolt per decade beyond the Boltzmann limit and a negative differential resistance with a peak-to-valley current ratio greater than 100 at room temperature. Multi-valued logic with a high inverter gain and reconfigurable logic states are further demonstrated. This work reports a multifunctional hot-emitter transistor with significant potential for low-power and negative-differential-resistance applications, marking a promising advancement for the post-Moore era.

2.
Sci Total Environ ; : 175373, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39117215

RESUMEN

Raw water pipelines are considered a significant pathway for human exposure to microplastics (MPs, <5 mm) in surface water. However, there is currently very limited information on the longitudinal distribution characteristics of microplastics in raw water pipelines. This study assessed the abundance and distribution characteristics of microplastics in surface water from two different water sources in Jiangsu Province during different seasons. The correlation between conventional water quality indicators and microplastics was also explored. Specifically, the longitudinal variation of microplastics in raw water pipelines was investigated. Results showed that microplastics were detected in both basins during different seasons. In Basin 1, the abundance of MPs ranged from 34 ±â€¯1 to 58 ±â€¯2 n/L in March and from 3 ±â€¯1 to 6.7 ±â€¯4 n/L in June. In Basin 2, the abundance ranged from 6.5 ±â€¯1 to 14 ±â€¯1 n/L in March and from 2 ±â€¯1 to 7.7 ±â€¯1 n/L in June. The abundance of microplastics showed a decreasing trend along the pipeline. Polymethyl methacrylate (PMMA) was the main polymer type detected in both basins. Polyethylene terephthalate (PE) and polyurethane (PU) showed higher removal rates in the pipeline due to their higher density. The predominant size ranges of microplastics in the raw water were 10-50 µm and 50-100 µm. Additionally, the average particle size of MPs increased with the transportation distance, likely due to microbial colonization. This study is the first comprehensive investigation of the distribution characteristics of microplastics in raw water pipeline systems. The removal of microplastics in raw water pipelines contributes significantly to the elimination of microplastics at the source. This research helps to fill the knowledge gap regarding the fate of microplastics in raw water pipeline systems.

3.
Eur J Pharmacol ; 981: 176903, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39154823

RESUMEN

BACKGROUND: Epilepsy is a prevalent disorder of the central nervous system. Approximately, one-third of patients show resistance to pharmacological interventions. The pathogenesis of epilepsy is complex, and neuronal apoptosis plays a critical role. Aberrantly reactive astrocytes, induced by cytokine release from activated microglia, may lead to neuronal apoptosis. This study investigated the role of glucagon-like peptide 1 receptor (GLP1R) in microglial activation in epilepsy and its impact on astrocyte-mediated neurotoxicity. METHODS: We used human hippocampal tissue from patients with temporal lobe epilepsy and a pilocarpine-induced epileptic mouse model to assess neurobiological changes in epilepsy. BV2 microglial cells and primary astrocytes were used to evaluate cytokine release and astrocyte activation in vitro. The involvement of GLP1R was explored using the GLP1R agonist, Exendin-4 (Ex-4). RESULTS: Our findings indicated that reduced GLP1R expression in hippocampal microglia in both epileptic mouse models and human patients, correlated with increased cytokine release and astrocyte activation. Ex-4 treatment restored microglial homeostasis, decreased cytokine secretion, and reduced astrocyte activation, particularly of the A1 phenotype. These changes were associated with a reduction in neuronal apoptosis. In addition, Ex-4 treatment significantly decreased the frequency and duration of seizures in epileptic mice. CONCLUSIONS: This study highlights the crucial role of microglial GLP1R in epilepsy pathophysiology. GLP1R downregulation contributes to microglial- and astrocyte-mediated neurotoxicity, exacerbating neuronal death and seizures. Activation of GLP1R with Ex-4 has emerged as a promising therapeutic strategy to reduce neuroinflammation, protect neuronal cells, and control seizures in epilepsy. This study provides a foundation for developing novel antiepileptic therapies targeting microglial GLP1R, with the potential to improve outcomes in patients with epilepsy.

4.
Alzheimers Res Ther ; 16(1): 187, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160571

RESUMEN

BACKGROUND: Posterior cortical atrophy (PCA) is a rare condition characterized by early-onset and progressive visual impairment. Individuals with PCA have relatively early-onset and progressive dementia, posing certain needs for early detection. Hence, this study aimed to investigate the association of alterations in outer retinal and choroidal structure and microvasculature with PCA neuroimaging and clinical features and the possible effects of apolipoprotein E(APOE) ε4 allele on outer retinal and choroidal alterations in participants with PCA, to detect potential ocular biomarkers for PCA screening. METHODS: This cross-sectional study included PCA and age- and sex-matched healthy control participants from June 2022 to December 2023. All participants with PCA completed a comprehensive neurological evaluation. All participants were recorded baseline information and underwent an ophthalmic evaluation. Quantitative analyses were performed using swept-source optical coherence tomography (SS-OCT) and angiography (SS-OCTA). Adaptive optics scanning laser ophthalmoscopy (AO-SLO) was performed in some patients. In participants with PCA, the influence of APOE ε4 on outer retinal and choroidal alterations and the correlation of outer retinal and choroidal alterations with PCA neuroimaging and clinical features in participants with PCA were investigated. RESULTS: A total of 28 participants (53 eyes) with PCA and 56 healthy control participants (112 eyes) were included in the current study. Compared with healthy control participants, participants with PCA had significantly reduced outer retinal thickness (ORT) (p < 0.001), choriocapillaris vessel density (VD) (p = 0.007), choroidal vascular index (CVI) (p = 0.005) and choroidal vascular volume (CVV) (p = 0.003). In participants with PCA, APOE ε4 carriers showed thinner ORT (p = 0.009), and increased choriocapillaris VD (p = 0.004) and CVI (p = 0.004). The PCA neuroimaging features were positively associated with the ORT, CVI and CVV. Furthermore, differential correlations were observed of PCA clinical features with the CRT, CVV and CVI. CONCLUSIONS: Our findings highlighted the association of outer retinal and choroidal alterations with PCA neuroimaging and clinical features in participants with PCA. Noninvasive SS-OCT and SS-OCTA can provide potential biomarkers for the diagnosis and management of PCA, improving awareness of PCA syndrome among ophthalmologists, neurologists, and primary care providers.


Asunto(s)
Coroides , Neuroimagen , Tomografía de Coherencia Óptica , Humanos , Masculino , Femenino , Estudios Transversales , Persona de Mediana Edad , Tomografía de Coherencia Óptica/métodos , Coroides/diagnóstico por imagen , Coroides/patología , Anciano , Neuroimagen/métodos , Atrofia/patología , Retina/diagnóstico por imagen , Retina/patología , Apolipoproteína E4/genética
5.
Int J Cosmet Sci ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39049756

RESUMEN

OBJECTIVE: Exploring the effects of age on microbial community structure and understanding the effects of chronological ageing as well as sun exposure on microbial community diversity. METHOD: The microbial characteristics of the facial skin of 98 adult women aged 18-70 years were studied using 16S rRNA gene sequencing, and differences based on age and reported sun exposure were assessed. RESULTS: The cheek skin's bacterial diversity and richness increased with age. The relative abundance of Cutibacterium decreased with age, while the relative abundance of Corynebacterium, Anaerococcus, Paracoccus, Micrococcus, Kocuria, Kytococcus, and Chryseobacterium increased. In addition, an increase in Micrococcus and a decrease in Cutibacterium were observed in volunteers with more than 2 h of daily sun exposure compared to volunteers with <2 h of daily sun exposure. Under low-sunlight conditions, Cutibacterium was more prevalent in the youth group, and Corynebacterium, Anaerococcus, and Kytococcus were more prevalent in the older group. CONCLUSION: The diversity and composition of the bacterial community on the cheeks are affected by age and extrinsic factors (sun exposure) may also play a role in this.


OBJECTIF: Étudier les effets de l'âge sur la structure de la communauté microbienne et comprendre les effets du vieillissement chronologique ainsi que de l'exposition au soleil sur la diversité de la communauté microbienne. MÉTHODE: Les caractéristiques microbiennes de la peau du visage de 98 femmes adultes âgées de 18 à 70 ans ont été étudiées à l'aide du séquençage génétique de l'ARNr 16S, et les différences basées sur l'âge et l'exposition au soleil rapportée ont été évaluées. RÉSULTAT: La diversité et la richesse bactériennes de la peau des joues ont augmenté avec l'âge. L'abondance relative de Cutibacterium a diminué avec l'âge, tandis que l'abondance relative de Corynebacterium, Anaerococcus, Paracoccus, Micrococcus, Kocuria, Kytococcus et Chryseobacterium a augmenté. De plus, une augmentation de Micrococcus et une diminution de Cutibacterium ont été observées chez des volontaires ayant été exposés au soleil pendant plus de 2 heures par jour par rapport à des volontaires ayant été exposés au soleil pendant moins de 2 heures par jour. Dans des conditions de faible luminosité, Cutibacterium était plus prévalent dans le bras des personnes jeunes, et Corynebacterium, Anaerococcus et Kytococcus étaient plus prévalents dans le bras des personnes plus âgées. CONCLUSION: La diversité et la composition de la communauté bactérienne sur les joues sont affectées par l'âge et des facteurs extrinsèques (exposition au soleil) peuvent également y jouer un rôle.

6.
Cell Genom ; 4(7): 100583, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38889719

RESUMEN

CRISPR mutagenesis screens conducted with SpCas9 and other nucleases have identified certain cis-regulatory elements and genetic variants but at a limited resolution due to the absence of protospacer adjacent motif (PAM) sequences. Here, leveraging the broad targeting scope of the near-PAMless SpRY variant, we have demonstrated that saturated SpRY mutagenesis and base editing screens can faithfully identify functional regulatory elements and essential genetic variants for target gene expression at single-base resolution. We further extended this methodology to investigate a genome-wide association study (GWAS) locus at 10q22.1 associated with a red blood cell trait, where we identified potential enhancers regulating HK1 gene expression, despite not all of these enhancers exhibiting typical chromatin signatures. More importantly, our saturated base editing screens pinpoint multiple causal variants within this locus that would otherwise be missed by Bayesian statistical fine-mapping. Our approach is generally applicable to functional interrogation of all non-coding genomic elements while complementing other high-coverage CRISPR screens.


Asunto(s)
Sistemas CRISPR-Cas , Estudio de Asociación del Genoma Completo , Humanos , Estudio de Asociación del Genoma Completo/métodos , Sistemas CRISPR-Cas/genética , Edición Génica/métodos , Mutagénesis , Elementos de Facilitación Genéticos/genética
7.
J Neurooncol ; 169(1): 203-213, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38916849

RESUMEN

PURPOSE: The treatment of leptomeningeal metastasis (LM), a serious complication of advanced non-small cell lung cancer (NSCLC), presents challenges, particularly in patients with EGFR exon 20 insertion (ex20ins) mutations. METHODS: This study retrospectively analyzed data from 10 EGFR ex20ins-mutated NSCLC patients with LM admitted at our institution from May 2011 to June 2023. Circulating tumor DNA (ctDNA) from cerebrospinal fluid (CSF) and matched plasma samples was analyzed using next-generation sequencing. All patients received high-dose furmonertinib combined with intraventricular chemotherapy (IVC) as salvage therapy. Data on patient demographics, treatment efficacy, and safety outcomes were collected. RESULTS: The most common insertion mutation identified in this study was p.A767_V769dup (n = 4, 40%), followed by D770-N771insY (n = 2, 20%). Nine patients had EGFR ex20ins occurring in the EGFR loop region following the C-helix, whereas only one patient had an EGFR ex20ins (A763_Y764insFQEA) occurring in the C-helix of the tyrosine kinase domain. LM response assessment using the RANO-LM criteria revealed that 6 patients (60%, 95% CI 26.2-87.8%) achieved a response, 3 had stable disease, and 1 had progressive disease. The median progression-free survival and overall survival were estimated to be 6.5 months and 8.8 months, respectively. The most commonly reported treatment-related adverse events were rash (n = 7) and diarrhea (n = 7), with no treatment-related deaths occurring. CONCLUSIONS: The current study demonstrated that high-dose furmonertinib plus IVC as salvage treatment for patients with LM harboring EGFR ex20ins mutations had promising clinical benefits and a manageable safety profile.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Receptores ErbB , Neoplasias Pulmonares , Terapia Recuperativa , Humanos , Masculino , Femenino , Persona de Mediana Edad , Receptores ErbB/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Anciano , Estudios Retrospectivos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Exones , Adulto , Mutación , Neoplasias Meníngeas/tratamiento farmacológico , Neoplasias Meníngeas/secundario , Neoplasias Meníngeas/genética , Carcinomatosis Meníngea/tratamiento farmacológico , Carcinomatosis Meníngea/secundario , Carcinomatosis Meníngea/genética , Estudios de Seguimiento , Pronóstico , Mutagénesis Insercional
8.
Mov Disord ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38894532

RESUMEN

BACKGROUND: Patients with Parkinson's disease (PD) respond to deep brain stimulation (DBS) variably. However, how brain substrates restrict DBS outcomes remains unclear. OBJECTIVE: In this article, we aim to identify prognostic brain signatures for explaining the response variability. METHODS: We retrospectively investigated a cohort of patients with PD (n = 141) between 2017 and 2022, and defined DBS outcomes as the improvement ratio of clinical motor scores. We used a deviation index to quantify individual perturbations on a reference structural covariance network acquired with preoperative T1-weighted magnetic resonance imaging. The neurobiological perturbations of patients were represented as z scored indices based on the chronological perturbations measured on a group of normal aging adults. RESULTS: After applying stringent statistical tests (z > 2.5) and correcting for false discoveries (P < 0.01), we found that accelerated deviations mainly affected the prefrontal cortex, motor strip, limbic system, and cerebellum in PD. Particularly, a negative network within the accelerated deviations, expressed as "more preoperative deviations, less postoperative improvements," could predict DBS outcomes (mean absolute error = 0.09, R2 = 0.15). Moreover, a fusion of personal brain predictors and medical responses significantly improved traditional evaluations of DBS outcomes. Notably, the most important brain predictor, a pathway connecting the cognitive unit (prefrontal cortex) and motor control unit (cerebellum and motor strip), partially mediates DBS outcomes with the age at surgery. CONCLUSIONS: Our findings suggest that individual structural perturbations on the cognitive motor control circuit are critical for modulating DBS outcomes. Interventions toward the circuit have the potential for additional clinical improvements. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

9.
Artículo en Inglés | MEDLINE | ID: mdl-38904613

RESUMEN

Objective: To analyze the efficacy and safety of bevacizumab combined with chemotherapy in the treatment of malignant pleural effusion of lung cancer. Methods: Lung cancer patients with malignant pleural effusion (n = 60 cases) treated in our hospital from January 2020 to December 2022 were retrospectively analyzed. They were divided into a control group (patients receiving conventional chemotherapy) and an observation group (patients receiving bevacizumab combined with chemotherapy). The two groups were age and sex-matched. The therapeutic effects, adverse reactions, quality of life (physiological status, social and family status, emotional status, and functional status), levels of serum tumor markers (cytokeratin 19 fragment, tumor-specific growth factor, and carcinoembryonic antigen), pain degree of the two groups before and after treatment, and the psychological states before and after treatment (anxiety and depression scores) of the two groups were compared. Results: The results obtained shows that the observation group has improved treatment outcome than the control group, P < .05. Similarly, the observation group reported higher physiological status, social and family status, emotional status, functional status and other quality of life compared to the control group, P < .05. Interestingly, the observation group showed lower levels of serum tumor markers than the control group, P < .05. Upon comparison of the pain degree of the two groups after treatment, the observation group reported a lesser degree of pain than the control group, P < .05. Although no significant difference was observed in the depression and anxiety scores of the two groups prior to the treatment, the observation group displayed improved psychological state compared to the control group, P < .05. Conclusion: Bevacizumab combined with chemotherapy has outstanding curative effect on malignant pleural effusion of lung cancer.

10.
J Environ Manage ; 359: 121013, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38723495

RESUMEN

Aquaculture pond sediments have a notable influence on the ecosystem balance and farmed animal health. In this study, microalgal-bacterial immobilization (MBI) was designed to improve aquaculture pond sediments via synergistic interactions. The physicochemical characteristics, bacterial communities, and the removal efficiencies of emerging pollutants were systematically investigated. The consortium containing diatom Navicula seminulum and Alcaligenes faecalis was cultivated and established in the free and immobilized forms for evaluating the treatment performance. The results indicated that the immobilized group exhibited superior performance in controlling nutrient pollutants, shaping and optimizing the bacterial community compositions with the enrichment of functional bacteria. Additionally, it showed a stronger positive correlation between the bacterial community shifts and nutrient pollutants removal compared to free cells. Furthermore, the immobilized system maintained the higher removal performance of emerging pollutants (heavy metals, antibiotics, and pathogenic Vibrios) than free group. These findings confirmed that the employment of immobilized N. seminulum and A. faecalis produced more synergistic benefits and exerted more improvements than free cells in ameliorating aquaculture pond sediments, suggesting the potential for engineering application of functional microalgal-bacterial consortium in aquaculture.


Asunto(s)
Acuicultura , Microalgas , Estanques , Microalgas/metabolismo , Sedimentos Geológicos/microbiología , Metales Pesados , Contaminantes Químicos del Agua/metabolismo , Bacterias/metabolismo , Animales
11.
Brief Bioinform ; 25(4)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38783704

RESUMEN

The untranslated region (UTR) of messenger ribonucleic acid (mRNA), including the 5'UTR and 3'UTR, plays a critical role in regulating gene expression and translation. Variants within the UTR can lead to changes associated with human traits and diseases; however, computational prediction of UTR variant effect is challenging. Current noncoding variant prediction mainly focuses on the promoters and enhancers, neglecting the unique sequence of the UTR and thereby limiting their predictive accuracy. In this study, using consolidated datasets of UTR variants from disease databases and large-scale experimental data, we systematically analyzed more than 50 region-specific features of UTR, including functional elements, secondary structure, sequence composition and site conservation. Our analysis reveals that certain features, such as C/G-related sequence composition in 5'UTR and A/T-related sequence composition in 3'UTR, effectively differentiate between nonfunctional and functional variant sets, unveiling potential sequence determinants of functional UTR variants. Leveraging these insights, we developed two classification models to predict functional UTR variants using machine learning, achieving an area under the curve (AUC) value of 0.94 for 5'UTR and 0.85 for 3'UTR, outperforming all existing methods. Our models will be valuable for enhancing clinical interpretation of genetic variants, facilitating the prediction and management of disease risk.


Asunto(s)
Regiones no Traducidas 3' , Regiones no Traducidas 5' , Humanos , Biología Computacional/métodos , Aprendizaje Automático , Variación Genética , Regiones no Traducidas
12.
Addict Behav ; 156: 108057, 2024 09.
Artículo en Inglés | MEDLINE | ID: mdl-38733952

RESUMEN

Problematic internet use (PIU) and depression usually co-occur and are common among college students. According to network theory, it may be attributed to the interplay of symptoms that connect these two mental health problems. However, most studies have failed to examine complex and subtle connections at the symptom level and have not clarified how PIU and depression symptoms are intercorrelated, which symptoms serve as the source of comorbidity (i.e., the central symptoms), and whether such a comorbidity mechanism would change with higher grades. To explore these questions, this study examined four contemporaneous networks and three cross-lagged panel networks, visualizing the symptoms as nodes and the connections between symptoms as edges. A total of 2,420 college students (Mage = 18.35, SD = 0.84; 67.98 % girls) completed four annual surveys. Overall, the results of contemporaneous networks and cross-lagged panel networks indicated that (a) PIU and depression symptoms are intercorrelated; (b) the core symptoms responsible for comorbidity mostly belonged to PIU, and (c) the comorbidity mechanism would change with time. These findings explain the dynamic relation between PIU and depression and identify possible primary symptoms that comorbidity programs can mitigate at different stages of the college years.


Asunto(s)
Comorbilidad , Trastorno de Adicción a Internet , Estudiantes , Humanos , Femenino , Masculino , Estudiantes/estadística & datos numéricos , Estudiantes/psicología , Adulto Joven , Adolescente , Trastorno de Adicción a Internet/epidemiología , Trastorno de Adicción a Internet/psicología , Universidades , China/epidemiología , Depresión/epidemiología , Depresión/psicología , Trastorno Depresivo/epidemiología , Trastorno Depresivo/psicología
13.
Vet Microbiol ; 293: 110083, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38593623

RESUMEN

Campylobacter spp., such as Campylobacter jejuni and Campylobacter coli, are important zoonotic Gram-negative pathogens that cause acute intestinal diseases in humans. In this study, a retrospective analysis was conducted on previously collected Campylobacter isolates from antimicrobial resistance surveillance. A total of 29 optrA-positive C. coli strains were identified and subjected to second-generation sequencing. Multilocus sequence typing and single nucleotide polymorphism analyses demonstrated that the 29 optrA-positive isolates were genetically homogeneous. Notably, among the 29 isolated strains, the ΔoptrA variants exhibit a nonsense mutation at position 979 where the base C is substituted by T, leading to the formation of a premature termination codon. The alignment of sequences and genetic environmental characteristics suggested that ΔoptrA located on a chromosomally carried multidrug-resistant genomic island. There are other resistant genes on the multidrug resistance genomic island, such as aph(2'')-If, aph(3')-III, aadE, tet(O), tet(L), cat, erm(A), optrA and blaOXA-61. As a result, the 29 ΔoptrA-positive strains displayed susceptibility to both florfenicol and linezolid. The ΔoptrA gene is linked to the erm(A) gene, resulting in the formation of translocatable unit (TU) that are encompassed by two copies of IS1216 mobile elements. Multiple occurrences of similar TUs have been documented in numerous C. coli and provided evidence for the significance of TUs in facilitating the transfer of drug resistance genes in C. coli.


Asunto(s)
Antibacterianos , Infecciones por Campylobacter , Campylobacter coli , Pollos , Farmacorresistencia Bacteriana Múltiple , Islas Genómicas , Campylobacter coli/genética , Campylobacter coli/efectos de los fármacos , Islas Genómicas/genética , Pollos/microbiología , Animales , Farmacorresistencia Bacteriana Múltiple/genética , Antibacterianos/farmacología , Infecciones por Campylobacter/microbiología , Infecciones por Campylobacter/veterinaria , Estudios Retrospectivos , Proteínas Bacterianas/genética , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Enfermedades de las Aves de Corral/microbiología , Polimorfismo de Nucleótido Simple
14.
Environ Res ; 252(Pt 3): 118923, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38636641

RESUMEN

Symbiotic nitrogen fixation of Chinese milk vetch (Astragalus sinicus L.) can fix nitrogen from the atmosphere and serve as an organic nitrogen source in agricultural ecosystems. Exogenous organic material application is a common practice of affecting symbiotic nitrogen fixation; however, the results of the regulation activities remain under discussion. Studies on the impact of organic amendments on symbiotic nitrogen fixation have focused on dissolved organic carbon content changes, whereas the impact on dissolved organic carbon composition and the underlying mechanism remain unclear. In situ pot experiments were carried out using soils from a 40-year-old field experiment platform to investigate symbiotic nitrogen fixation rate trends, dissolved organic carbon concentration and component, and diazotroph community structure in roots and in rhizosphere soils following long-term application of different exogenous organic substrates, i.e., green manure, green manure and pig manure, and green manure and rice straw. Remarkable increases in rate were observed in and when compared with that in green manure treatment, with the greatest enhancement observed in the treatment. Moreover, organic amendments, particularly pig manure application, altered diazotroph community composition in rhizosphere soils, therefore increasing the abundance of the host-specific genus Mesorhizobium. Furthermore, organic amendments influence the diazotroph communities through two primary mechanisms. Firstly, the components of dissolved organic carbon promote an increase in available iron, facilitated by the presence of humus substrates. Secondly, the elevated content of dissolved organic carbon and available iron expands the niche breadth of Mesorhizobium within the rhizosphere. Consequently, these alterations result in a modified diazotroph community within the rhizosphere, which in turn influences Mesorhizobium nodulation in the root and symbiotic nitrogen fixation rate. The results of the present study enhance our understanding of the impact of organic amendments on symbiotic nitrogen fixation and the underlying mechanism, highlighting the key role of dissolved organic carbon composition on diazotroph community composition in the rhizosphere.


Asunto(s)
Planta del Astrágalo , Mesorhizobium , Fijación del Nitrógeno , Rizosfera , Microbiología del Suelo , Simbiosis , Mesorhizobium/fisiología , Planta del Astrágalo/microbiología , Planta del Astrágalo/química , Estiércol/microbiología , Estiércol/análisis , Animales , Raíces de Plantas/microbiología , Suelo/química
15.
ACS Appl Bio Mater ; 7(5): 3469-3482, 2024 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-38651365

RESUMEN

Bacterial invasion hinders the healing process of wound, leading to the formation of chronic infected wound; meanwhile, the misuse of antibiotics has resulted in the emergence of numerous drug-resistant bacteria. The application of conventional antimicrobial methods and wound treatment techniques is not appropriate for wound dressings. In this paper, quaternized poly(vinyl alcohol) (QPVA) and pomegranate-like copper uniformly doped polydopamine nanoparticles (PDA@Cu) were introduced into a gelatin-oxidized carboxymethyl cellulose system to form a multicomponent synergistic antibacterial hydrogel (GOQ3P3). Polydopamine improves the biocompatibility and prevents the detachment of Cu nanoparticles. It can achieve synergistic antibacterial effects through quaternary ammonium salt-inorganic nanoparticle photothermal treatment under 808 nm near-infrared (NIR) irradiation. It exhibits highly efficient and rapid bactericidal properties against Escherichia coli, Staphylococcus aureus, and MRSA (methicillin-resistant Staphylococcus aureus) with an antibacterial rate close to 100%. The gel scaffold composed of macromolecules gives the hydrogel excellent mechanical properties, adhesive capabilities, self-healing characteristics, biocompatibility, and pH degradation and promotes cell adhesion and migration. In a full-thickness wound healing model infected with MRSA, GOQ3P3 controls inflammatory responses, accelerates collagen deposition, promotes angiogenesis, and enhances wound closure in the wound healing cascade reaction. This study provides a feasible strategy for constructing dressings targeting chronic infection wounds caused by drug-resistant bacteria.


Asunto(s)
Antibacterianos , Materiales Biocompatibles , Carboximetilcelulosa de Sodio , Escherichia coli , Gelatina , Hidrogeles , Ensayo de Materiales , Pruebas de Sensibilidad Microbiana , Cicatrización de Heridas , Antibacterianos/farmacología , Antibacterianos/química , Gelatina/química , Cicatrización de Heridas/efectos de los fármacos , Carboximetilcelulosa de Sodio/química , Carboximetilcelulosa de Sodio/farmacología , Hidrogeles/química , Hidrogeles/farmacología , Escherichia coli/efectos de los fármacos , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Ratones , Staphylococcus aureus/efectos de los fármacos , Tamaño de la Partícula , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Polímeros/química , Polímeros/farmacología , Indoles/química , Indoles/farmacología , Cobre/química , Cobre/farmacología , Humanos
16.
Sci Total Environ ; 932: 172780, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38685428

RESUMEN

The vegetation phenology, encompassing the start (SOS) and end (EOS) of the growing season on the Tibetan Plateau, has been significantly impacted by global climate change. Furthermore, ozone (O3) has gradually become the main pollutant in this region, substantially influencing carbon cycle and ecosystems on Earth. While ongoing studies have focused mainly on the implications of climate parameters, including temperature, precipitation, and radiation, the effects of O3 on the SOS and EOS remain unclear. Here, we compared the responses and sensitivities of the SOS and EOS to both climatic factors and O3 in this region. With the use of partial correlation analysis, we found that increased precipitation was the most important factor influencing the SOS and caused earlier occurrence (4.8 % vs. 21.9 %) for most plant functional types. In comparison, temperature only dominated in shrublands. In particular, we found that the EOS responded comparably to climatic factors with similar proportions between advancing and delaying patterns. However, higher O3 levels consistently advanced the EOS for almost all plant functional types and was the main factor controlling EOS variations based on the sensitivity analysis. Our results emphasized that O3 pollution should be considered for obtaining better phenological forecasts and determining the impacts of the environment and atmospheric composition on carbon sequestration in terrestrial ecosystems.


Asunto(s)
Contaminantes Atmosféricos , Cambio Climático , Ozono , Ozono/análisis , Tibet , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Ecosistema , Estaciones del Año , Desarrollo de la Planta/efectos de los fármacos , Plantas/efectos de los fármacos
17.
J Agric Food Chem ; 72(18): 10282-10294, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38657235

RESUMEN

This study explores the antipathogenic properties of volatile organic compounds (VOCs) produced by Bacillus velezensis LT1, isolated from the rhizosphere soil of Coptis chinensis. The impact of these VOCs on the mycelial growth of Sclerotium rolfsii LC1, the causative agent of southern blight in C. chinensis, was evaluated using a double Petri-dish assay. The biocontrol efficacy of these VOCs was further assessed through leaf inoculation and pot experiments. Antifungal VOCs were collected using headspace solid-phase microextraction (SPME), and their components were identified via gas chromatography-mass spectrometry (GC-MS). The results revealed that the VOCs significantly inhibited the mycelial growth and sclerotia germination of S. rolfsii LC1 and disrupted the morphological integrity of fungal mycelia. Under the influence of these VOCs, genes associated with chitin synthesis were upregulated, while those related to cell wall degrading enzymes were downregulated. Notably, 2-dodecanone and 2-undecanone exhibited inhibition rates of 81.67% and 80.08%, respectively. This research provides a novel approach for the prevention and management of southern blight in C. chinensis, highlighting the potential of microbial VOCs in biocontrol strategies.


Asunto(s)
Bacillus , Basidiomycota , Coptis , Enfermedades de las Plantas , Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/farmacología , Compuestos Orgánicos Volátiles/metabolismo , Bacillus/química , Bacillus/metabolismo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Basidiomycota/química , Basidiomycota/metabolismo , Coptis/química , Coptis/microbiología , Fungicidas Industriales/farmacología , Fungicidas Industriales/química , Cromatografía de Gases y Espectrometría de Masas , Micelio/química , Micelio/crecimiento & desarrollo , Micelio/efectos de los fármacos
18.
Front Microbiol ; 15: 1337655, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38500587

RESUMEN

Introduction: Southern blight, caused by Sclerotium rolfsii, poses a serious threat to the cultivation of Coptis chinensis, a plant with significant medicinal value. The overreliance on fungicides for controlling this pathogen has led to environmental concerns and resistance issues. There is an urgent need for alternative, sustainable disease management strategies. Methods: In this study, Bacillus velezensis LT1 was isolated from the rhizosphere soil of diseased C. chinensis plants. Its biocontrol efficacy against S. rolfsii LC1 was evaluated through a confrontation assay. The antimicrobial lipopeptides in the fermentation liquid of B. velezensis LT1 were identified using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS). The effects of B. velezensis LT1 on the mycelial morphology of S. rolfsii LC1 were examined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Results: The confrontation assay indicated that B. velezensis LT1 significantly inhibited the growth of S. rolfsii LC1, with an inhibition efficiency of 78.41%. MALDI-TOF-MS analysis detected the presence of bacillomycin, surfactin, iturin, and fengycin in the fermentation liquid, all known for their antifungal properties. SEM and TEM observations revealed that the mycelial and cellular structures of S. rolfsii LC1 were markedly distorted when exposed to B. velezensis LT1. Discussion: The findings demonstrate that B. velezensis LT1 has considerable potential as a biocontrol agent against S. rolfsii LC1. The identified lipopeptides likely contribute to the antifungal activity, and the morphological damage to S. rolfsii LC1 suggests a mechanism of action. This study underscores the importance of exploring microbial biocontrol agents as a sustainable alternative to chemical fungicides in the management of plant diseases. Further research into the genetic and functional aspects of B. velezensis LT1 could provide deeper insights into its biocontrol mechanisms and facilitate its application in agriculture.

19.
Free Radic Res ; 58(3): 156-169, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38478853

RESUMEN

Sepsis is a systemic inflammatory response syndrome caused by infection, which causes renal dysfunction known as sepsis-associated acute kidney injury (S-AKI). Ferroptosis is a form of lipid peroxidation dependent on iron and reactive oxygen species that differs from other forms of programmed cell death at the morphological and biochemical levels. Andrographolide (AG), a natural diterpenoid lactone compound extracted from Andrographis paniculata, has been shown to have therapeutic effects in kidney disease. In this study, we investigated the novel mechanism by which AG attenuates septic acute kidney injury by inhibiting ferroptosis in renal tubular epithelial cells (HK-2) through the Nrf2/FSP1 pathway. Cecum ligation and puncture (CLP)-induced septic rats and lipopolysaccharide (LPS)-induced HK-2 cells were used for in vivo and in vitro experiments. Firstly, in septic rats and HK-2 cells, AG effectively decreased the levels of kidney injury indicators, including blood creatinine, urea nitrogen, and markers of kidney injury such as neutrophil gelatinase-associated lipid transport protein and kidney injury molecule-1 (KIM-1). In addition, AG prevented ferroptotosis, by avoiding the accumulation of iron and lipid peroxidation, and an increase in SLC7A11 and GPX4 in AG-treated HK-2 cells. Furthermore, AG attenuated mitochondrial damage, including mitochondrial swelling, outer membrane rupture, and a reduction in mitochondrial cristae in LPS-treated HK-2 cells. Ferrostatin-1 (Fer-1), a ferroptosis inhibitor, significantly inhibited LPS-induced ferroptosis in HK-2 cells. Importantly, our results confirm that Nrf2/FSP1 is an important pathway for ferroptosis resistance. Nrf2 siRNA hindered the effect of AG in attenuating acute kidney injury and inhibiting ferroptosis. These findings demonstrate that Nrf2/FSP1-mediated HK-2 ferroptosis is associated with AG, alleviates septic acute kidney injury, and indicates a novel avenue for therapeutic interventions in the treatment of acute kidney injury in sepsis.


Asunto(s)
Lesión Renal Aguda , Diterpenos , Ferroptosis , Factor 2 Relacionado con NF-E2 , Sepsis , Ferroptosis/efectos de los fármacos , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , Sepsis/metabolismo , Diterpenos/farmacología , Diterpenos/uso terapéutico , Lesión Renal Aguda/tratamiento farmacológico , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/etiología , Lesión Renal Aguda/patología , Animales , Factor 2 Relacionado con NF-E2/metabolismo , Ratas , Masculino , Humanos , Ratas Sprague-Dawley
20.
Food Chem X ; 21: 101198, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38370303

RESUMEN

This study focused on analyzing the aroma formation mechanism of retronasal muscat flavor in table grapes. The sensory characteristics and fragrance components of table grape juice with different intensities of Muscat were investigated using GC-Quadrupole-MS, quantitative descriptive analysis and three-alternate forced choice. Free monoterpenoids were the main contributors to the retronasal Muscat flavor. The contribution of Muscat compounds to this flavor was quantified by Stevens coefficient, the most and the least sensitive compounds to concentration changes were citronellol and linalool, respectively. To predict the Muscat flavor intensity by mathematical modeling, established a model between Muscat flavor intensity and monoterpenoids concentration, and an optimal partial least squares regression model with a linear relationship between natural logarithms was obtained. These findings provide reference for understanding the formation mechanism of specific aromas in fruits and provide a basis for the development and quality control of processed products such as Muscat flavor grape juice.

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