RESUMEN

Although wind power contributes to the reduction of greenhouse gas emissions, it also has significant impacts on the local climate and vegetation. Exploring these impacts is important for the sustainable development of wind power. Therefore, based on moderate-resolution imaging spectroradiometer (MODIS) data and other remote sensing data from 2003 to 2022, this paper investigated the impacts of 101 grassland wind farms (WFs) in Inner Mongolia on land-atmosphere water and heat exchange, vegetation growth, ecosystem primary productivity, and vegetation structural characteristics during the growing season and revealed the spatial distribution patterns of the impacts of WFs as well as differences between different types of grasslands. The results indicated that WFs increased the nighttime land surface temperature (LST), decreased evapotranspiration (ET), inhibited vegetation growth, decreased gross primary productivity (GPP), and reduced the leaf area index (LAI) in growing season grasslands. This effect varied across different types of grasslands and showed significant complexity. In terms of land-atmosphere water and heat exchange, nighttime LST increases and ET decreases were significant in the typical steppe but not in the meadow steppe. In terms of vegetation change, meadow steppe had the most inhibited vegetation growth and the greatest reduction in GPP. In terms of the impact range, WFs on typical steppe and meadow steppe have opposite effects on vegetation growth and ecosystem primary productivity inside and outside of them, i.e., they inhibit vegetation growth and reduce GPP inside the WF areas but promote vegetation growth and increase GPP outside the WF areas. Compared with previous studies, this study analyzed multiple climate and vegetation indicators based on many WF samples, which reduced the uncertainty associated with a single sample and provided more comprehensive and comparable observations of different types of grasslands. These findings can help to balance the relationship between wind power development and ecological protection.

RESUMEN

Aeromonas hydrophila, the pathogen that is the causative agent of motile Aeromonas septicemia (MAS) disease, commonly attacks freshwater fishes, including yellow catfish (Pelteobagrus fulvidraco). Although the kidney is one of the most important organs involved in immunity in fish, its role in disease progression has not been fully elucidated. Understanding the cellular composition and innate immune regulation mechanisms of the kidney of yellow catfish is important for the treatment of MAS. In this study, single-cell RNA sequencing (scRNA-seq) was performed on the kidney of hybrid yellow catfish (Pelteobagrus fulvidraco ♀ × Pelteobagrus vachelli ♂) after A. hydrophila infection. Nine types of kidney cells were identified using marker genes, and a transcription module of marker genes in the main immune cells of hybrid yellow catfish kidney tissue was constructed using in-situ hybridization. In addition, the single-cell transcriptome data showed that the differentially expressed genes of macrophages were primarily enriched in the Toll-like receptor and Nod-like receptor signaling pathways. The expression levels of genes involved in these pathways were upregulated in macrophages following A. hydrophila infection. Transmission electron microscopy and TUNEL analysis revealed the cellular characteristics of macrophages before and after A. hydrophila infection. These data provide empirical support for in-depth research on the role of the kidney in the innate immune response of hybrid yellow catfish.

Asunto(s)

Aeromonas hydrophila , Bagres , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Inmunidad Innata , Riñón , Transcriptoma , Animales , Bagres/inmunología , Bagres/genética , Aeromonas hydrophila/fisiología , Enfermedades de los Peces/inmunología , Inmunidad Innata/genética , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/veterinaria , Transcriptoma/inmunología , Riñón/inmunología , Proteínas de Peces/genética , Proteínas de Peces/inmunología , Análisis de la Célula Individual

RESUMEN

BACKGROUND: Facial palsy, often resulting from trauma or iatrogenic treatments, leads to significant esthetic and functional impairment. Surgical interventions, such as masseteric-to-facial nerve transfer combined with static suspension, are frequently recommended to restore facial nerve function and symmetry. METHODS: This study examines how Botulinum Toxin A (BoNT-A) treatment on the unaffected side affects facial symmetry and brain connectivity in patients with severe oral commissure droop from facial nerve damage. Patients were divided into two groups: one received BoNT-A injections on the unaffected side, and the other did not. RESULTS: Our findings revealed that BoNT-A treatment not only improved facial symmetry but also induced significant modifications in brain functional network connectivity. These modifications extended beyond the sensorimotor network, involving high-level cognitive processes, and exhibited a significant correlation with the degree of facial asymmetry. CONCLUSIONS: These results provide valuable insights into the mechanisms underlying the positive effects of BoNT-A intervention on motor recovery and brain plasticity in facial palsy patients. Furthermore, the study emphasizes the importance of a multidisciplinary approach to facial palsy rehabilitation. Understanding these intricate interactions between facial symmetry restoration and brain network adaptations may pave the way for more effective treatments and improved quality of life for individuals dealing with facial palsy.

RESUMEN

With childhood hypertension emerging as a global public health concern, understanding its associated factors is crucial. This study investigated the prevalence and associated factors of hypertension among Chinese children. This cross-sectional investigation was conducted in Pinghu, Zhejiang province, involving 2,373 children aged 8-14 years from 12 schools. Anthropometric measurements were taken by trained staff. Blood pressure (BP) was measured in three separate occasions, with an interval of at least two weeks. Childhood hypertension was defined as systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) ≥ age-, sex-, and height-specific 95th percentile, across all three visits. A self-administered questionnaire was utilized to collect demographic, socioeconomic, health behavioral, and parental information at the first visit of BP measurement. Random forest (RF) and multivariable logistic regression model were used collectively to identify associated factors. Additionally, population attributable fractions (PAFs) were calculated. The prevalence of childhood hypertension was 5.0% (95% confidence interval [CI]: 4.1-5.9%). Children with body mass index (BMI) ≥ 85th percentile were grouped into abnormal weight, and those with waist circumference (WC) > 90th percentile were sorted into central obesity. Normal weight with central obesity (NWCO, adjusted odds ratio [aOR] = 5.04, 95% CI: 1.96-12.98), abnormal weight with no central obesity (AWNCO, aOR = 4.60, 95% CI: 2.57-8.21), and abnormal weight with central obesity (AWCO, aOR = 9.94, 95% CI: 6.06-16.32) were associated with an increased risk of childhood hypertension. Childhood hypertension was attributable to AWCO mostly (PAF: 0.64, 95% CI: 0.50-0.75), followed by AWNCO (PAF: 0.34, 95% CI: 0.19-0.51), and NWCO (PAF: 0.13, 95% CI: 0.03-0.30). Our results indicated that obesity phenotype is associated with childhood hypertension, and the role of weight management could serve as potential target for intervention.

Asunto(s)

Hipertensión , Humanos , Estudios Transversales , Masculino , Femenino , Hipertensión/epidemiología , China/epidemiología , Niño , Prevalencia , Adolescente , Factores de Riesgo , Modelos Logísticos , Bosques Aleatorios

RESUMEN

The emergence of sliding ferroelectricity facilitates low-barrier ferroelectrics in two-dimensional materials, while limited electric polarizations impede practical applications. Herein, we propose an effective strategy to enlarge the polarization by introducing an intrinsic electric field, exemplified by Janus transition metal dichalcogenides (TMDs) with the first-principle calculations. The intrinsic electric field is introduced and regulated by leveraging the electronegativity differences among chalcogens. An improved polarization is achieved in the Janus TeMoS bilayer with a polarization of 1.18 pC/m, a 65% enhancement compared to normal TMD bilayers. Through differential charge density analysis, the inner mechanism is attributed to the effects of intrinsic electric fields on charge redistribution. Furthermore, the feasibility of polarization reversal is determined by evaluating switching barriers and the responses under an electric field. The provided proposal is applicable and available for broader systems and will pave the way for the development of novel electronic devices.

RESUMEN

BACKGROUND: Right ventricular-pulmonary artery coupling (RVPAC) refers to the relationship between right ventricular systolic force and afterload. The ratio of echocardiograph-derived tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP) has been proposed as a noninvasive measurement of RVPAC and reported as an independent prognostic parameter of heart failure. However, it has not been adequately in detail evaluated in heart failure with preserved ejection fraction (HFpEF). We hypothesized that RVPAC may be used and proposed as an expression of key risk factors in patients with HFpEF. METHODS: We retrospectively analyzed TAPSE/PASP of 648 HFpEF patients hospitalized in Chongqing Hospital of Traditional Chinese Medicine from January 1, 2016 to January 1, 2017. All eligible patients were followed up for 5 years. The correlation between TAPSE/SPAP index and clinical indicators and outcomes was evaluated. RESULTS: The final analysis included 414 patients. Nonsurvivors had significantly lower TAPSE, TAPSE/PASP and higher PASP compared with survivors (p < 0.0001). ROC curve analysis showed that the optimal cutoff of TAPSE, PASP, and RVPAC to predict all-cause death were 16.5 mm, 37.5 mmHg, and 0.45 mm/mmHg, respectively. In multivariate Cox regression analyses adjusted for gender showed a significant, independent association of the RVPAC with the composite endpoint of all-cause death or HF-related recurrent hospitalization (HR: 0.006; 95% CI 0.001-0.057, p < 0.001). CONCLUSIONS: RVPAC, defined by the ratio of TAPSE to PASP, is the expression of a key risk factor in HFpEF patients, which is independently associated with the composite endpoint of all-cause death or HF-related recurrent hospitalization.

Asunto(s)

Insuficiencia Cardíaca , Arteria Pulmonar , Volumen Sistólico , Función Ventricular Derecha , Humanos , Masculino , Femenino , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/diagnóstico , Volumen Sistólico/fisiología , Arteria Pulmonar/fisiopatología , Arteria Pulmonar/diagnóstico por imagen , Estudios Retrospectivos , Anciano , Función Ventricular Derecha/fisiología , Pronóstico , Factores de Riesgo , Persona de Mediana Edad , Ecocardiografía , Ventrículos Cardíacos/fisiopatología , Ventrículos Cardíacos/diagnóstico por imagen , China/epidemiología , Estudios de Seguimiento

RESUMEN

Background: Sex difference has long been recognized at cancer incidence, outcomes, and responses to therapy. Analyzing the somatic mutation profiles of large-scale cancer samples between the sexes have revealed several potential drivers of cancer with sex difference. However, it is still a demand for in-depth scrutinizing the sex-biased characteristics of genome instability to link the clinical differences for individual cancer type. Methods: Here, we utilized a published framework devised to specifically compare the copy number profiles between 2 groups to identify the sex-biased copy number alterations (CNAs) across 16 cancer types from the The Cancer Genome Atlas Program database, and dissected the impact of those CNAs. Results: Totally, 81 male-biased CNA regions and 23 female-biased CNA regions in 16 cancer types were found. Functional annotation analysis showed that several critical biological functions associated with sex-biased CNAs are shared in multiple cancer types, including immune-related pathways and regulation of cellular signaling. Most sex-biased CNAs have a substantial effect on transcriptional consequence, where the average of over 68% of genes have a linear relationship with CNAs across cancer types, and 14% of those genes are affected by the combination of the sex and copy number. Furthermore, 29 sex-biased CNA regions show latent capacity to be sex-specific prognostic biomarker such as CNA on 11q13.4 for head and neck cancer and lung cancer. Conclusions: This analysis offers new insights into the role of sex in cancer etiology and prognosis through a detailed characterization of sex differences in genome instability of diverse cancers.

RESUMEN

Protein-peptide interactions (PPepIs) are vital to understanding cellular functions, which can facilitate the design of novel drugs. As an essential component in forming a PPepI, protein-peptide binding sites are the basis for understanding the mechanisms involved in PPepIs. Therefore, accurately identifying protein-peptide binding sites becomes a critical task. The traditional experimental methods for researching these binding sites are labor-intensive and time-consuming, and some computational tools have been invented to supplement it. However, these computational tools have limitations in generality or accuracy due to the need for ligand information, complex feature construction, or their reliance on modeling based on amino acid residues. To deal with the drawbacks of these computational algorithms, we describe a geometric attention-based network for peptide binding site identification (GAPS) in this work. The proposed model utilizes geometric feature engineering to construct atom representations and incorporates multiple attention mechanisms to update relevant biological features. In addition, the transfer learning strategy is implemented for leveraging the protein-protein binding sites information to enhance the protein-peptide binding sites recognition capability, taking into account the common structure and biological bias between proteins and peptides. Consequently, GAPS demonstrates the state-of-the-art performance and excellent robustness in this task. Moreover, our model exhibits exceptional performance across several extended experiments including predicting the apo protein-peptide, protein-cyclic peptide and the AlphaFold-predicted protein-peptide binding sites. These results confirm that the GAPS model is a powerful, versatile, stable method suitable for diverse binding site predictions.

Asunto(s)

Péptidos , Sitios de Unión , Péptidos/química , Péptidos/metabolismo , Unión Proteica , Biología Computacional/métodos , Algoritmos , Proteínas/química , Proteínas/metabolismo , Aprendizaje Automático

RESUMEN

Huangjiu is a spontaneously fermented alcoholic beverage, that undergoes intricate microbial compositional changes. This study aimed to unravel the flavor and quality formation mechanisms based on the microbial metabolism of Huangjiu. Here, metagenome techniques, chemometrics analysis, and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) metabolomics combined with microbial metabolic network were employed to investigate the distinctions and relationship between the microbial profiles and the quality characteristics, flavor metabolites, functional metabolic patterns of Huangjiu across three regions. Significant variations (P < 0.05) were observed in metabolic rate of physicochemical parameters and biogenic amine concentration among three regions. 8 aroma compounds (phenethyl acetate, phenylethyl alcohol, isobutyl alcohol, ethyl octanoate, ethyl acetate, ethyl hexanoate, isoamyl alcohol, and diethyl succinate) out of 448 volatile compounds were identified as the regional chemical markers. 25 dominant microbial genera were observed through metagenomic analysis, and 13 species were confirmed as microbial markers in three regions. A metabolic network analysis revealed that Saccharomycetales (Saccharomyces), Lactobacillales (Lactobacillus, Weissella, and Leuconostoc), and Eurotiales (Aspergillus) were the predominant populations responsible for substrate, flavor (mainly esters and phenylethyl alcohol) metabolism, Lactobacillales and Enterobacterales were closely linked with biogenic amine. These findings provide scientific evidence for regional microbial contributions to geographical characteristics of Huangjiu, and perspectives for optimizing microbial function to promote Huangjiu quality.

Asunto(s)

Bacterias , Fermentación , Cromatografía de Gases y Espectrometría de Masas , Redes y Vías Metabólicas , Metagenómica , Oryza , Compuestos Orgánicos Volátiles , Vino , Bacterias/clasificación , Bacterias/metabolismo , Bacterias/genética , Bacterias/aislamiento & purificación , Aminas Biogénicas/análisis , Aminas Biogénicas/metabolismo , China , Aromatizantes/metabolismo , Aromatizantes/química , Metabolómica/métodos , Microbiota , Odorantes/análisis , Oryza/microbiología , Oryza/química , Oryza/metabolismo , Microextracción en Fase Sólida , Gusto , Compuestos Orgánicos Volátiles/metabolismo , Compuestos Orgánicos Volátiles/análisis , Vino/análisis , Vino/microbiología

RESUMEN

The synthetic community of lactic acid bacteria (LAB) is commonly utilized in the food industry for manipulating product properties. However, the intermediate interactions and ecological stability resulting from metabolic differences among various LAB types remain poorly understood. We aimed to analyze the metabolic behavior of single and combined lactic acid bacteria in China rice wine based on microbial succession. Three-stage succession patterns with obligate heterofermentative LAB dominating prefermentation and homofermentative LAB prevailing in main fermentation were observed. Facultative heterofermentative LAB exhibited significant growth. Pairwise coculture interactions revealed 63.5% positive, 34.4% negative, and 2.1% neutral interactions, forming nontransitive and transitive competition modes. Nontransitive competitive combinations demonstrated stability over ∼200 generations through amino acid (mainly aspartic acid, glutamine, and serine) cross-feeding and lactic acid detoxification, which also showed potential for controlling biogenic amines and developing LAB starter cultures. Our findings offer insights into the mechanistic underpinnings of LAB interaction networks.

Asunto(s)

Fermentación , Ácido Láctico , Lactobacillales , Oryza , Vino , China , Ácido Láctico/metabolismo , Lactobacillales/metabolismo , Interacciones Microbianas , Oryza/microbiología , Oryza/metabolismo , Oryza/química , Vino/análisis , Vino/microbiología

RESUMEN

In recent years, cyclic peptides have emerged as a promising therapeutic modality due to their diverse biological activities. Understanding the structures of these cyclic peptides and their complexes is crucial for unlocking invaluable insights about protein target-cyclic peptide interaction, which can facilitate the development of novel-related drugs. However, conducting experimental observations is time-consuming and expensive. Computer-aided drug design methods are not practical enough in real-world applications. To tackles this challenge, we introduce HighFold, an AlphaFold-derived model in this study. By integrating specific details about the head-to-tail circle and disulfide bridge structures, the HighFold model can accurately predict the structures of cyclic peptides and their complexes. Our model demonstrates superior predictive performance compared to other existing approaches, representing a significant advancement in structure-activity research. The HighFold model is openly accessible at https://github.com/hongliangduan/HighFold.

Asunto(s)

Disulfuros , Péptidos Cíclicos , Péptidos Cíclicos/química , Disulfuros/química , Programas Informáticos , Modelos Moleculares , Conformación Proteica , Algoritmos , Biología Computacional/métodos

RESUMEN

General, catalytic and enantioselective construction of chiral α,α-dialkyl indoles represents an important yet challenging objective to be developed. Herein we describe a cobalt catalyzed enantioselective anti-Markovnikov alkene hydroalkylation via the remote stereocontrol for the synthesis of α,α-dialkyl indoles and other N-heterocycles. This asymmetric C(sp3)-C(sp3) coupling features high flexibility in introducing a diverse set of alkyl groups at the α-position of chiral N-heterocycles. The utility of this methodology has been demonstrated by late-stage functionalization of drug molecules, asymmetric synthesis of bioactive molecules, natural products and functional materials, and identification of a class of molecules exhibiting anti-apoptosis activities in UVB-irradiated HaCaT cells. Ligands play a vital role in controlling the reaction regioselectivity. Changing the ligand from bi-dentate L6 to tridentate L12 enables CoH-catalyzed Markovnikov hydroalkylation. Mechanistic studies disclose that the anti-Markovnikov hydroalkylation involves a migratory insertion process while the Markovnikov hydroalkylation involves a MHAT process.

RESUMEN

The accessory proteins of coronaviruses play a crucial role in facilitating virus-host interactions and modulating host immune responses. Previous study demonstrated that the NS7a protein of porcine deltacoronavirus (PDCoV) partially hindered the host immune response by impeding the induction of IFN-α/ß. However, the potential additional functions of NS7a protein in evading innate immunity have yet to be elucidated. This study aimed to investigate the mechanism of PDCoV NS7a protein regulating the JAK/STAT signaling pathway. We presented evidence that NS7a effectively inhibited ISRE promoter activity and ISGs transcription. NS7a hindered STAT1 phosphorylation, interacted with STAT2 and IRF9, and further impeded the formation and nuclear accumulation of ISGF3. Furthermore, comparative analysis of NS7a across different PDCoV strains revealed that the mutation of Leu4 to Pro4 led to an increase in the molecular weights of NS7a and disrupted its inhibition on the JAK/STAT signaling pathway. This finding implied that NS7a with key amino acids may be an indicator of virulence for PDCoV strains. Taken together, this study revealed a novel role of NS7a in antagonizing the IFN-I signaling pathway.

Asunto(s)

Deltacoronavirus , Quinasas Janus , Transducción de Señal , Animales , Porcinos , Quinasas Janus/genética , Factores de Transcripción STAT/genética , Factor 3 de Genes Estimulados por el Interferón

RESUMEN

BACKGROUND: Surfactin, a green lipopeptide bio-surfactant, exhibits excellent surface, hemolytic, antibacterial, and emulsifying activities. However, a lack of clear understanding of the synthesis regulation mechanism of surfactin homologue components has hindered the customized production of surfactin products with different biological activities. RESULTS: In this study, exogenous valine and 2-methylbutyric acid supplementation significantly facilitated the production of C14-C15 surfactin proportions (up to 75% or more), with a positive correlation between the homologue proportion and fortified concentration. Subsequently, the branched-chain amino acid degradation pathway and the glutamate synthesis pathway are identified as critical pathways in regulating C14-C15 surfactin synthesis by transcriptome analysis. Overexpression of genes bkdAB and glnA resulted in a 1.4-fold and 1.3-fold increase in C14 surfactin, respectively. Finally, the C14-rich surfactin was observed to significantly enhance emulsification activity, achieving an EI24 exceeding 60% against hexadecane, while simultaneously reducing hemolytic activity. Conversely, the C15-rich surfactin demonstrated an increase in both hemolytic and antibacterial activities. CONCLUSION: This study presents the first evidence of a potential connection between surfactin homologue synthesis and the conversion of glutamate and glutamine, providing a theoretical basis for targeting the synthesis regulation and structure-activity relationships of surfactin and other lipopeptide compounds.

Asunto(s)

Ácidos Grasos , Tensoactivos , Ácidos Grasos/metabolismo , Tensoactivos/metabolismo , Ácido Glutámico/metabolismo , Lipopéptidos , Antibacterianos/farmacología , Antibacterianos/metabolismo , Péptidos Cíclicos/química , Bacillus subtilis/genética

RESUMEN

Interlayer excitons, with prolonged lifetimes and tunability, hold potential for advanced optoelectronics. Previous research on the interlayer excitons has been dominated by two-dimensional heterostructures. Here, we construct WSe2/GaN composite heterostructures, in which the doping concentration of GaN and the twist angle of bilayer WSe2 are employed as two ingredients for the manipulation of exciton behaviors and polarizations. The exciton energies in monolayer WSe2/GaN can be regulated continuously by the doping levels of the GaN substrate, and a remarkable increase in the valley polarizations is achieved. Especially in a heterostructure with 4°-twisted bilayer WSe2, a maximum polarization of 38.9% with a long lifetime is achieved for the interlayer exciton. Theoretical calculations reveal that the large polarization and long lifetime are attributed to the high exciton binding energy and large spin flipping energy during depolarization in bilayer WSe2/GaN. This work introduces a distinctive member of the interlayer exciton with a high degree of polarization and a long lifetime.

RESUMEN

Traffic light optimization is known to be a cost-effective method for reducing congestion and energy consumption in urban areas without changing physical road infrastructure. However, due to the high installation and maintenance costs of vehicle detectors, most intersections are controlled by fixed-time traffic signals that are not regularly optimized. To alleviate traffic congestion at intersections, we present a large-scale traffic signal re-timing system that uses a small percentage of vehicle trajectories as the only input without reliance on any detectors. We develop the probabilistic time-space diagram, which establishes the connection between a stochastic point-queue model and vehicle trajectories under the proposed Newellian coordinates. This model enables us to reconstruct the recurrent spatial-temporal traffic state by aggregating sufficient historical data. Optimization algorithms are then developed to update traffic signal parameters for intersections with optimality gaps. A real-world citywide test of the system was conducted in Birmingham, Michigan, and demonstrated that it decreased the delay and number of stops at signalized intersections by up to 20% and 30%, respectively. This system provides a scalable, sustainable, and efficient solution to traffic light optimization and can potentially be applied to every fixed-time signalized intersection in the world.

RESUMEN

The O-glycosylation of polyphenols for the synthesis of glycosides has garnered substantial attention in food research applications. However, the practical utility of UDP-glycosyltransferases (UGTs) is significantly hindered by their low catalytic efficiency and suboptimal regioselectivity. The concurrent optimization of the regioselectivity and activity during the glycosylation of polyphenols presents a formidable challenge. Here, we addressed the long-standing activity-regioselectivity tradeoff in glycosyltransferase UGTBL1 through systematic enzyme engineering. The optimal combination of mutants, N61S/I62M/D63W/A208R/P218W/R282W (SMWRW1W2), yielded a 6.1-fold improvement in relative activity and a 17.3-fold increase in the ratio of gastrodin to para-hydroxybenzyl alcohol-4'-O-ß-glucoside (with 89.5% regioselectivity for gastrodin) compared to those of the wild-type enzyme and ultimately allowed gram-scale production of gastrodin (1,066.2 mg/L) using whole-cell biocatalysis. In addition, variant SMWRW1W2 exhibited a preference for producing phenolic glycosides from several substrates. This study lays the foundation for the engineering of additional UGTs and the practical applications of UGTs in regioselective retrofitting.

Asunto(s)

Alcoholes Bencílicos , Glicósidos , Glicosiltransferasas , Uridina Difosfato , Glucósidos , Fenoles , Polifenoles

RESUMEN

With the rapid development of nanotechnology and biomedicine, numerous gadolinium (Gd)-based nanoparticle MRI contrast agents have been widely investigated. Due to the unique physicochemical properties of nanoparticles and the complexity of biological systems, the biosafety of Gd-based nanoparticle MRI contrast agents has been paid more and more attention. Herein, for the first time, we employed an ultra-high performance liquid chromatography-electrospray ionization quadrupole time-of-flight/mass spectrometry (UPLC-ESI-QTOF/MS)-based metabolomics approach to investigate the potential toxicity of Gd-based nanoparticle MRI contrast agents. In this work, NaGdF4 and PEG-NaGdF4 nanoparticles were successfully constructed and selected as the representative Gd-based nanoparticle MRI contrast agents for the metabolomics analysis. Based on the results of metabolomics, more metabolic biomarkers and pathways were identified in the NaGdF4 group than those in the PEG-NaGdF4 group. Careful analysis of these metabolic biomarkers and pathways suggested that NaGdF4 nanoparticles induced disturbance of pyrimidine and purine metabolism, inflammatory response, and kidney injury to a certain extent compared with PEG-NaGdF4 nanoparticles. These results indicated that Gd-based nanoparticle contrast agents modified with PEG had better biosafety. Additionally, it was demonstrated that the discovery of characteristic metabolomics biomarkers induced by nanoparticles would provide a new approach for biosafety assessment and stimulate the development of nanomedicine.

Asunto(s)

Medios de Contraste , Nanopartículas , Medios de Contraste/toxicidad , Medios de Contraste/química , Contención de Riesgos Biológicos , Gadolinio/química , Nanopartículas/toxicidad , Nanopartículas/química , Imagen por Resonancia Magnética/métodos , Biomarcadores

RESUMEN

Bacterial infection is a key factor affecting wound healing. Conventional treatments might lead to the widespread emergence of drug-resistant bacteria due to the long-term and excessive use of antibiotics. It is necessary to develop an antibiotic-free method for effective treatment of bacterial wound infections. In this work, we constructed an antibiotic-free polysaccharide-based hydrogel dressing (ATB) with near-infrared light-actuated on-demand botanicals release and hyperthermia for the synergistic treatment of wound infections. The ATB hydrogel dressing was made up of agarose as a support matrix, berberine hydrochloride as the active botanicals and TA-Fe(III) nanoparticles as NIR laser-activated photothermal reagents. The ATB hydrogel dressing showed spatiotemporal botanicals release and excellent photothermal properties with NIR irradiation. With the results of in vitro and in vivo antibacterial experiments, the antibiotic-free ATB hydrogel could synergistically eliminate bacteria and accelerate wound healing. Overall, the near-infrared light-responsive ATB hydrogel could provide a promising antibiotic-free strategy for the treatment of bacterial wound infections.

Asunto(s)

Hipertermia Inducida , Infección de Heridas , Humanos , Hidrogeles/farmacología , Compuestos Férricos , Hipertermia , Polisacáridos/farmacología , Rayos Infrarrojos , Vendajes , Antibacterianos/farmacología , Infección de Heridas/tratamiento farmacológico

RESUMEN

Charge and spin are two intrinsic attributes of carriers governing almost all of the physical processes and operation principles in materials. Here, we demonstrate the manipulation of electronic and spin states in designed Co-quantum dot/WS2 (Co-QDs/WS2) heterostructures by employing a metal-dielectric composite substrate and via scanning tunneling microscope. By repeatedly scanning under a unipolar bias, switching the bias polarity, or applying a pulse through nonmagnetic or magnetic tips, the Co-QDs morphologies exhibit a regular and reproducible transformation between bright and dark dots. First-principles calculations reveal that these tunable characters are attributed to the variation of density of states and the transition of magnetic anisotropy energy induced by carrier accumulation. It also suggests that the metal-dielectric composite substrate is successful in creating the interfacial potential for carrier accumulation and realizes the electrically controllable modulations. These results will promote the exploration of electron-matter interactions in quantum systems and provide an innovative way to facilitate the development of spintronics.