Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 438
Filtrar
1.
Artículo en Inglés | MEDLINE | ID: mdl-38949731

RESUMEN

To maximize the efficiency of biomass waste utilization and waste management, a novel acid-modified magnetic biomass spent coffee grounds (NiFe2O4/SCG) was obtained by pyrolysis at 473 K and co-precipitation methods and employed to eliminate bivalent mercury (Hg(II)) in water bodies. The prepared NiFe2O4/SCG adsorbent exhibits remarkable magnetism with a strength of 45.78 emu/g and can easily be separated from water via a magnetic force. The adsorption of Hg(II) over the NiFe2O4/SCG has an optimal conditions of pH = 8, T = 39 ℃, and dosage of 0.055 g/L, and the maximal adsorption capacity for Hg(II) is 167.44 mg/g via Response Surface Methodology optimization. The removal of Hg(II) over NiFe2O4/SCG primarily involves ion exchange, electrostatic attraction, and chelation; conforms to the pseudo-second-order kinetic and Langmuir models; and is an endothermic reaction. Additionally, the magnetic biomass NiFe2O4/SCG has good regeneration capability and stability. The application research reveal that inorganic salt ions, nitrogen fertilizer urea, humus, and other contaminants in different actual water bodies (river water, lake water, and the effluent of sewage treatment plant) have little effect on the adsorption of Hg(II) over the NiFe2O4/SCG. The prepared adsorbent NiFe2O4/SCG has practical application value for removing Hg(II) from water bodies.

2.
Adv Sci (Weinh) ; : e2405077, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38959393

RESUMEN

Energy and environmental issues have increasingly garnered significant attention for sustainable development. Flexible and shape-stable phase change materials display great potential in regulation of environmental temperature for energy saving and human comfort. Here, inspired by the water absorption behavior of salt-tolerant animals and plants in salinity environment and the Hofmeister theory, highly stable phase change salogels (PCSGs) are fabricated through in situ polymerization of hydrophilic monomers in molten salt hydrates, which can serve multiple functions including thermal management patches, smart windows, and ice blocking coatings. The gelation principles of the polymer in high ion concentration solution are explored through the density functional theory simulation and verified the feasibility of four types of salt hydrates. The high concentration chaotropic ions strongly interacted with polymer chains and promoted the gelation at low polymer concentrations which derive highly-stable and ultra-moisturizing PCSGs with high latent heat (> 200 J g-1). The synergistic adhesion and transparency switching abilities accompanied with phase transition enable their smart thermal management. The study resolves the melting leakage and thermal cycling stability of salt hydrates, and open an avenue to fabricate flexible PCM of low cost, high latent heat, and long-term durability for energy-saving, ice-blocking, and thermal management.

3.
Sci Rep ; 14(1): 15218, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956343

RESUMEN

The optimized layout of electric vehicle (EV) chargers is not only crucial for users' convenience but also a key element in urban sustainable development, energy transition, and the promotion of new energy vehicles. In order to provide a basis for the problem of localization and capacity determination of chargers and compare the merits of several mainstream algorithms, this paper first establishes an optimization model with the objective of minimizing the total investment cost of all the chargers and the constraint of meeting the charging demands of all electric vehicles. Optimizations were performed using genetic algorithm (GA), surrogate optimization algorithm (SOA), and mixed integer linear programming (MILP) algorithm, respectively. In the case of using MILP, the original nonlinear optimization problem was transformed into a linear problem. In the planning of city-level EV chargers, MILP took 14182.57 s to calculate the minimum cost of 34.62 million yuan. After retaining only 10% of the original data amount, SOA took 87651.34 s to calculate the minimum cost of 3.01 million yuan. The results indicate that GA is prone to falling into local optima and is not suitable for large-scale optimization problems. SOA, on the other hand, requires significant memory consumption, so the issue of memory usage needs to be carefully considered when using it directly. Although MILP is only applicable to linear programming problems, it has the advantages of lower memory usage and higher reliability if the problem can be transformed into a linear one.

4.
Sci Rep ; 14(1): 13652, 2024 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-38871809

RESUMEN

Simple and practical tools for screening high-risk new-onset diabetes after percutaneous coronary intervention (PCI) (NODAP) are urgently needed to improve post-PCI prognosis. We aimed to evaluate the risk factors for NODAP and develop an online prediction tool using conventional variables based on a multicenter database. China evidence-based Chinese medicine database consisted of 249, 987 patients from 4 hospitals in mainland China. Patients ≥ 18 years with implanted coronary stents for acute coronary syndromes and did not have diabetes before PCI were enrolled in this study. According to the occurrence of new-onset diabetes mellitus after PCI, the patients were divided into NODAP and Non-NODAP. After least absolute shrinkage and selection operator regression and logistic regression, the model features were selected and then the nomogram was developed and plotted. Model performance was evaluated by the receiver operating characteristic curve, calibration curve, Hosmer-Lemeshow test and decision curve analysis. The nomogram was also externally validated at a different hospital. Subsequently, we developed an online visualization tool and a corresponding risk stratification system to predict the risk of developing NODAP after PCI based on the model. A total of 2698 patients after PCI (1255 NODAP and 1443 non-NODAP) were included in the final analysis based on the multicenter database. Five predictors were identified after screening: fasting plasma glucose, low-density lipoprotein cholesterol, hypertension, family history of diabetes and use of diuretics. And then we developed a web-based nomogram ( https://mr.cscps.com.cn/wscoringtool/index.html ) incorporating the above conventional factors for predicting patients at high risk for NODAP. The nomogram showed good discrimination, calibration and clinical utility and could accurately stratify patients into different NODAP risks. We developed a simple and practical web-based nomogram based on multicenter database to screen for NODAP risk, which can assist clinicians in accurately identifying patients at high risk of NODAP and developing post-PCI management strategies to improved patient prognosis.


Asunto(s)
Diabetes Mellitus , Nomogramas , Intervención Coronaria Percutánea , Humanos , Intervención Coronaria Percutánea/efectos adversos , Masculino , Femenino , Persona de Mediana Edad , Factores de Riesgo , Anciano , Diabetes Mellitus/epidemiología , Internet , China/epidemiología , Medición de Riesgo/métodos , Pronóstico , Síndrome Coronario Agudo/diagnóstico , Curva ROC
5.
Mater Horiz ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38894682

RESUMEN

Hydrogels with intricate 3D networks and high hydrophilicity have qualities resembling those of biological tissues, making them ideal candidates for use as smart biomedical materials. Reactive oxygen species (ROS) responsive hydrogels are an innovative class of smart hydrogels, and are cross-linked by ROS-responsive modules through covalent interactions, coordination interactions, or supramolecular interactions. Due to the introduction of ROS response modules, this class of hydrogels exhibits a sensitive response to the oxidative stress microenvironment existing in organisms. Simultaneously, due to the modularity of the ROS-responsive structure, ROS-responsive hydrogels can be manufactured on a large scale through additive manufacturing. This review will delve into the design, fabrication, and applications of ROS-responsive hydrogels. The main goal is to clarify the chemical principles that govern the response mechanism of these hydrogels, further providing new perspectives and methods for designing responsive hydrogel materials.

6.
J Colloid Interface Sci ; 674: 437-444, 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38941936

RESUMEN

Self-assembly of nanoclusters (NCs) is an effective synthetic method for preparing functionalized nanomaterials. However, the assembly process and mechanisms in solutions still remain ambiguous owing to the limited strategies to monitor intermediate assembled states. Herein, the self-assembly process of amphiphilic molecule 4POSS-DL-POM (consisting of four polyhedral oligomeric silsesquioxanes, a dendritic linker, and one polyoxometalate) by evaporation of acetone in a mixed acetone/n-decane solution is monitored by time-resolved synchrotron small-angle X-ray scattering (SAXS). Scattering data assessments, including Kratky analysis, pair distance distribution function, and model fitting, track the self-assembly process of 4POSS-DL-POM from a fractal network to compact NCs, then to core-shell NCs, and finally to superlattice structure. The calculated average aggregation number of a core-shell NC is 11 according to the parameters obtained from core-shell model fitting, in agreement with electron microscopy. The fundamental understanding of the self-assembly dynamics from heterocluster into NCs provides principles to control building block shape and guide target aggregation, which can further promote the design and construction of highly ordered cluster-assembled functional nanomaterials.

8.
Phytomedicine ; 130: 155737, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38772183

RESUMEN

BACKGROUND: Caenorhabditis elegans (C. elegans) has been recognized for being a useful model organism in small-molecule drug screens and drug efficacy investigation. However, there remain bottlenecks in evaluating such processes as drug uptake and distribution due to a lack of appropriate chemical tools. PURPOSE: This study aims to prepare fluorescence-labeled leonurine as an example to monitor drug uptake and distribution of small molecule in C. elegans and living cells. METHODS: FITC-conjugated leonurine (leonurine-P) was synthesized and characterized by LC/MS, NMR, UV absorption and fluorescence intensity. Leonurine-P was used to stain C. elegans and various mammalian cell lines. Different concentrations of leonurine were tested in conjunction with a competing parent molecule to determine whether leonurine-P and leonurine shared the same biological targets. Drug distribution was analyzed by imaging. Fluorometry in microplates and flow cytometry were performed for quantitative measurements of drug uptake. RESULTS: The UV absorption peak of leonurine-P was 490∼495 nm and emission peak was 520 nm. Leonurine-P specifically bound to endogenous protein targets in C. elegans and mammalian cells, which was competitively blocked by leonurine. The highest enrichment levels of leonurine-P were observed around 72 h following exposure in C. elegans. Leonurine-P can be used in a variety of cells to observe drug distribution dynamics. Flow cytometry of stained cells can be facilely carried out to quantitatively detect probe signals. CONCLUSIONS: The strategy of fluorescein-labeled drugs reported herein allows quantification of drug enrichment and visualization of drug distribution, thus illustrates a convenient approach to study phytodrugs in pharmacological contexts.


Asunto(s)
Caenorhabditis elegans , Ácido Gálico , Animales , Ácido Gálico/análogos & derivados , Ácido Gálico/farmacocinética , Ácido Gálico/metabolismo , Humanos , Fluoresceína-5-Isotiocianato/análogos & derivados , Citometría de Flujo , Fluorescencia , Colorantes Fluorescentes
9.
Catal Sci Technol ; 14(9): 2390-2399, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38721397

RESUMEN

Transaminase enzymes are well established biocatalysts that are used in chemical synthesis due to their beneficial sustainability profile, regio- and stereoselectivity and substrate specificity. Here, the use of a wild-type Chromobacterium violaceum transaminase (CvTAm) in enzyme cascades revealed the formation of a novel hydroxystyryl pyridine product. Subsequent studies established it was a transaminase mediated reaction where it was exhibiting apparent aldolase reactivity. This promiscuous enzyme reaction mechanism was then explored using other wild-type transaminases and via the formation of CvTAm mutants. Application of one pot multi-step enzyme cascades was subsequently developed to produce a range of hydroxystyryl pyridines.

10.
Adv Sci (Weinh) ; : e2400349, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713747

RESUMEN

Critical-size bone defects pose a formidable challenge in clinical treatment, prompting extensive research efforts to address this problem. In this study, an inorganic-organic multifunctional composite hydrogel denoted as PLG-g-TA/VEGF/Sr-BGNPs is developed, engineered for the synergistic management of bone defects. The composite hydrogel demonstrated the capacity for mineralization, hydroxyapatite formation, and gradual release of essential functional ions and vascular endothelial growth factor (VEGF) and also maintained an alkaline microenvironment. The composite hydrogel promoted the proliferation and osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs), as indicated by increased expression of osteogenesis-related genes and proteins in vitro. Moreover, the composite hydrogel significantly enhanced the tube-forming capability of human umbilical vein endothelial cells (HUVECs) and effectively inhibited the process of osteoblastic differentiation of nuclear factor kappa-B ligand (RANKL)-induced Raw264.7 cells and osteoclast bone resorption. After the implantation of the composite hydrogel into rat cranial bone defects, the expression of osteogenic and angiogenic biomarkers increased, substantiating its efficacy in promoting bone defect repair in vivo. The commendable attributes of the multifunctional composite hydrogel underscore its pivotal role in expediting hydrogel-associated bone growth and repairing critical bone defects, positioning it as a promising adjuvant therapy candidate for large-segment bone defects.

11.
Front Oncol ; 14: 1365255, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38725635

RESUMEN

Objective: The optimal first-line immunotherapy regimen for patients with PD-L1 expression ≥50% in squamous non-small cell lung cancer (Sq-NSCLC) remains uncertain. This study utilized net-work meta-analysis (NMA) to indirectly compare the efficacy of various first-line immuno-therapy regimens in this patient subset. Methods: Systematic searches were conducted across PubMed, the Cochrane Library, Web of Science, and Embase databases for randomized controlled trials reporting overall survival (OS) and progression-free survival (PFS) outcomes. The search spanned from database inception to November 3, 2023. Bayesian network meta-analysis was employed for a comprehen-sive analysis. To ensure scientific rigor and transparency, this study is registered in the Interna-tional Prospective Register of Systematic Reviews (PROSPERO) under the registration number CRD42022349712. Results: The NMA encompassed 9 randomized controlled trials (RCTs), involving 2170 patients and investigating 9 distinct immunotherapy regimens. For OS, the combination of camrelizumab and chemotherapy demonstrated the highest probability (36.68%) of efficacy, fol-lowed by cemiplimab (33.86%) and atezolizumab plus chemotherapy (23.87%). Regarding PFS, the camrelizumab and chemotherapy combination had the highest probability (39.70%) of efficacy, followed by pembrolizumab (22.88%) and pembrolizumab plus chemotherapy (17.69%). Compared to chemotherapy, first-line treatment with immune checkpoint inhibitors (ICIs) in Sq-NSCLC pa-tients exhibited significant improvements in OS (HR 0.59, 95% CI 0.47-0.75) and PFS (HR 0.44, 95% CI 0.37-0.52). Conclusion: This study suggests that, for Sq-NSCLC patients with PD-L1 expression ≥50%, the first-line immunotherapy regimen of camrelizumab plus chemotherapy provides superior OS and PFS outcomes. Furthermore, ICIs demonstrate enhanced efficacy compared to chemotherapy in this patient population. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier: CRD 42022349712.

12.
ACS Appl Mater Interfaces ; 16(15): 18855-18866, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38577763

RESUMEN

Solar-driven interfacial evaporation provides a promising pathway for sustainable freshwater and energy generation. However, developing highly efficient photothermal and photocatalytic nanomaterials is challenging. Herein, substoichiometric molybdenum oxide (MoO3-x) nanoparticles are synthesized via step-by-step reduction treatment of l-cysteine under mild conditions for simultaneous photothermal conversion and photocatalytic reactions. The MoO3-x nanoparticles of low reduction degree are decorated on hydrophilic cotton cloth to prepare a MCML evaporator toward rapid water production, pollutant degradation, as well as electricity generation. The obtained MCML evaporator has a strong local light-to-heat effect, which can be attributed to excellent photothermal conversion via the local surface plasmon resonance effect in MoO3-x nanoparticles and the low heat loss of the evaporator. Meanwhile, the rich surface area of MoO3-x nanoparticles and the localized photothermal effect together effectively accelerate the photocatalytic degradation reaction of the antibiotic tetracycline. With the benefit of these advantages, the MCML evaporator attains a superior evaporation rate of 4.14 kg m-2 h-1, admirable conversion efficiency of 90.7%, and adequate degradation efficiency of 96.2% under 1 sun irradiation. Furthermore, after being rationally assembled with a thermoelectric module, the hybrid device can be employed to generate 1.0 W m-2 of electric power density. This work presents an effective complementary strategy for freshwater production and sewage treatment as well as electricity generation in remote and off-grid regions.

13.
Cardiovasc Diabetol ; 23(1): 123, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38581039

RESUMEN

BACKGROUND: Diabetes is a predominant driver of coronary artery disease worldwide. This study aims to unravel the distinct characteristics of oral and gut microbiota in diabetic coronary heart disease (DCHD). Simultaneously, we aim to establish a causal link between the diabetes-driven oral-gut microbiota axis and increased susceptibility to diabetic myocardial ischemia-reperfusion injury (MIRI). METHODS: We comprehensively investigated the microbial landscape in the oral and gut microbiota in DCHD using a discovery cohort (n = 183) and a validation chohort (n = 68). Systematically obtained oral (tongue-coating) and fecal specimens were subjected to metagenomic sequencing and qPCR analysis, respectively, to holistically characterize the microbial consortia. Next, we induced diabetic MIRI by administering streptozotocin to C57BL/6 mice and subsequently investigated the potential mechanisms of the oral-gut microbiota axis through antibiotic pre-treatment followed by gavage with specific bacterial strains (Fusobacterium nucleatum or fecal microbiota from DCHD patients) to C57BL/6 mice. RESULTS: Specific microbial signatures such as oral Fusobacterium nucleatum and gut Lactobacillus, Eubacterium, and Roseburia faecis, were identified as potential microbial biomarkers in DCHD. We further validated that oral Fusobacterium nucleatum and gut Lactobacillus are increased in DCHD patients, with a positive correlation between the two. Experimental evidence revealed that in hyperglycemic mice, augmented Fusobacterium nucleatum levels in the oral cavity were accompanied by an imbalance in the oral-gut axis, characterized by an increased coexistence of Fusobacterium nucleatum and Lactobacillus, along with elevated cardiac miRNA-21 and a greater extent of myocardial damage indicated by TTC, HE, TUNEL staining, all of which contributed to exacerbated MIRI. CONCLUSION: Our findings not only uncover dysregulation of the oral-gut microbiota axis in diabetes patients but also highlight the pivotal intermediary role of the increased abundance of oral F. nucleatum and gut Lactobacillus in exacerbating MIRI. Targeting the oral-gut microbiota axis emerges as a potent strategy for preventing and treating DCHD. Oral-gut microbial transmission constitutes an intermediate mechanism by which diabetes influences myocardial injury, offering new insights into preventing acute events in diabetic patients with coronary heart disease.


Asunto(s)
Enfermedad de la Arteria Coronaria , Diabetes Mellitus , Microbioma Gastrointestinal , Humanos , Animales , Ratones , Ratones Endogámicos C57BL , Fusobacterium nucleatum/fisiología , Enfermedad de la Arteria Coronaria/etiología
14.
Small ; : e2401731, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38682736

RESUMEN

Natural polyphenolic compounds play a vital role in nature and are widely utilized as building blocks in the fabrication of emerging functional nanomaterials. Although diverse fabrication methodologies are developed in recent years, the challenges of purification, uncontrollable reaction processes and additional additives persist. Herein, a modular and facile methodology is reported toward the fabrication of natural polyphenolic nanoparticles. By utilizing low frequency ultrasound (40 kHz), the assembly of various natural polyphenolic building blocks is successfully induced, allowing for precise control over the particle formation process. The resulting natural polyphenolic nanoparticles possessed excellent in vitro antioxidative abilities and in vivo therapeutic effects in typical oxidative stress models including wound healing and acute kidney injury. This study opens new avenues for the fabrication of functional materials from naturally occurring building blocks, offering promising prospects for future advancements in this field.

15.
ACS Appl Mater Interfaces ; 16(17): 22493-22503, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38647220

RESUMEN

Poly(levodopa) nanoparticles (P(l-DOPA) NPs) are another kind of melanin mimetic besides well-established polydopamine nanoparticles (PDA NPs). Due to the presence of carboxyl groups, the oxidative polymerization of l-DOPA to obtain particles was not as efficient as that of dopamine. Several established methods toward P(l-DOPA) NP fabrication do not combine convenience, morphological regularity, size controllability, low cost, and adaptability to metal-free application scenarios. In this work, P(l-DOPA) NPs were successfully prepared in hot water with the assistant of organic quaternary ammonium, due to the extra physical cross-linking mediated by cations. The employed physical interactions could also be affected by quaternary ammonium structure (i.e., number of cation heads, length of alkyl chain) to achieve different polymerization acceleration effects. The obtained P(l-DOPA) NPs retained superior photothermal properties and outperformed PDA-based melanin materials. Furthermore, P(l-DOPA) NPs were used in photothermal tumor therapy and showed better efficacy. This study offers new insights into the synthesis of melanin-like materials, as well as new understanding of the interaction between quaternary ammonium and bioinspired polyphenolic materials.


Asunto(s)
Dihidroxifenilalanina/análogos & derivados , Indoles , Levodopa , Melaninas , Nanopartículas , Compuestos de Amonio Cuaternario , Compuestos de Amonio Cuaternario/química , Compuestos de Amonio Cuaternario/farmacología , Nanopartículas/química , Melaninas/química , Animales , Ratones , Levodopa/química , Terapia Fototérmica , Humanos , Línea Celular Tumoral , Polímeros/química , Polímeros/síntesis química , Polímeros/farmacología
16.
Nat Commun ; 15(1): 3124, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600164

RESUMEN

Crop wild relatives offer natural variations of disease resistance for crop improvement. Here, we report the isolation of broad-spectrum powdery mildew resistance gene Pm36, originated from wild emmer wheat, that encodes a tandem kinase with a transmembrane domain (WTK7-TM) through the combination of map-based cloning, PacBio SMRT long-read genome sequencing, mutagenesis, and transformation. Mutagenesis assay reveals that the two kinase domains and the transmembrane domain of WTK7-TM are critical for the powdery mildew resistance function. Consistently, in vitro phosphorylation assay shows that two kinase domains are indispensable for the kinase activity of WTK7-TM. Haplotype analysis uncovers that Pm36 is an orphan gene only present in a few wild emmer wheat, indicating its single ancient origin and potential contribution to the current wheat gene pool. Overall, our findings not only provide a powdery mildew resistance gene with great potential in wheat breeding but also sheds light into the mechanism underlying broad-spectrum resistance.


Asunto(s)
Ascomicetos , Triticum , Triticum/genética , Fitomejoramiento , Genes de Plantas , Ascomicetos/genética , Mapeo Cromosómico , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genética
17.
Biosens Bioelectron ; 257: 116329, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38677023

RESUMEN

Considerable effort has been invested in developing salicylic acid (SA) biosensors for various application purposes. Here, by engineering the sensing modules and host cell chassis, we have gradually optimized the NahR-Psal/Pr-based SA biosensor, increasing the sensitivity and maximum output by 17.2-fold and 9.4-fold, respectively, and improving the detection limit by 800-fold, from 80 µM to 0.1 µM. A portable SA sensing device was constructed by embedding a gelatin-based hydrogel containing an optimized biosensor into the perforations of tape adhered to glass slide, which allowed good determination of SA in the range of 0.1 µM-10 µM. Then, we developed a customized smartphone App to measure the fluorescence intensity of each perforation and automatically calculate the corresponding SA concentration so that we could detect SA concentrations in real cosmetic samples. We anticipate that this smartphone-based imaging biosensor, with its compact size, higher sensitivity, cost-effectiveness, and easy data transfer, will be useful for long-term monitoring of SA.


Asunto(s)
Técnicas Biosensibles , Límite de Detección , Ácido Salicílico , Teléfono Inteligente , Técnicas Biosensibles/instrumentación , Ácido Salicílico/análisis , Ácido Salicílico/química , Diseño de Equipo , Humanos , Hidrogeles/química , Cosméticos/química , Cosméticos/análisis
18.
ACS Macro Lett ; 13(4): 401-406, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38511967

RESUMEN

In nature, proteins possess the remarkable ability to sense and respond to mechanical forces, thereby triggering various biological events, such as bone remodeling and muscle regeneration. However, in synthetic systems, harnessing the mechanical force to induce material growth still remains a challenge. In this study, we aimed to utilize low-frequency ultrasound (US) to activate horseradish peroxidase (HRP) and catalyze free radical polymerization. Our findings demonstrate the efficacy of this mechano-enzymatic chemistry in rapidly remodeling the properties of materials through cross-linking polymerization and surface coating. The resulting samples exhibited a significant enhancement in tensile strength, elongation, and Young's modulus. Moreover, the hydrophobicity of the surface could be completely switched within just 30 min of US treatment. This work presents a novel approach for incorporating mechanical sensing and rapid remodeling capabilities into materials.


Asunto(s)
Fenómenos Mecánicos , Polimerizacion , Módulo de Elasticidad , Resistencia a la Tracción , Ultrasonografía
19.
Biomacromolecules ; 25(4): 2563-2573, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38485470

RESUMEN

In the current years, polydopamine nanoparticles (PDA NPs) have been extensively investigated as an eumelanin mimic. However, unlike natural eumelanin, PDA NPs contain no 5,6-dihydroxyindole-2-carboxylic acid (DHICA)-derived units and may be limited in certain intrinsic properties; superior eumelanin-like nanomaterials are still actively being sought. Levodopa (l-DOPA) is a natural eumelanin precursor and expected to convert into DHICA and further remain within the final product through covalent or physical interactions. Herein, poly(levodopa) nanoparticles [P(l-DOPA) NPs] were synthesized with the assistance of zinc oxide as a supplement to synthetic eumelanin. This study found that P(l-DOPA) NPs had ∼90% DHICA-derived subunits on their surface and exhibited superior antioxidant activity compared to PDA NPs due to their looser polymeric microstructure. Benefitting from a stronger ROS scavenging ability, P(l-DOPA) NPs outperformed PDA NPs in treating cellular oxidative stress and acute inflammation. This research opens up new possibilities for the development and application of novel melanin-like materials.


Asunto(s)
Levodopa , Melaninas , Humanos , Melaninas/química , Antioxidantes , Inflamación/tratamiento farmacológico
20.
Pestic Biochem Physiol ; 199: 105786, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38458686

RESUMEN

Ipconazole is a broad-spectrum triazole fungicide that is highly effective against Fusarium pseudograminearum. However, its risk of developing resistance and mechanism are not well understood in F. pseudograminearum. Here, the sensitivities of 101 F. pseudograminearum isolates to ipconazole were investigated, and the average EC50 value was 0.1072 µg/mL. Seven mutants resistant to ipconazole were obtained by fungicide adaption, with all but one showing reduced fitness relative to the parental isolates. Cross-resistance was found between ipconazole and mefentrifluconazole and tebuconazole, but none between ipconazole and pydiflumetofen, carbendazim, fludioxonil, or phenamacril. In summary, these findings suggest that there is a low risk of F. pseudograminearum developing resistance to ipconazole. Additionally, a point mutation, G464S, was seen in FpCYP51B and overexpression of FpCYP51A, FpCYP51B and FpCYP51C was observed in ipconazole-resistant mutants. Assays, including transformation and molecular docking, indicated that G464S conferred ipconazole resistance in F. pseudograminearum.


Asunto(s)
Fungicidas Industriales , Fusarium , Farmacorresistencia Fúngica/genética , Fungicidas Industriales/farmacología , Simulación del Acoplamiento Molecular , Fusarium/genética , Desmetilación , Enfermedades de las Plantas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...