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Nitric oxide (NO) has received growing attention as an effective antibacterial agent with broad-spectrum activity and a low risk of resistance. However, it remains challenging to develop effective, controllable, and biocompatible NO-releasing materials. Here, we report a novel NO nanogenerator (AL-BNN6-PEG) self-assembled by lignin, a UV-absorbing and hydrophobic NO donor (N,N'-disec-butyl-N,N'-dinitroso-1,4-phenylenediamine, BNN6), and PEG-DSPE2000. It was discovered that upon visible light irradiation (450-460 nm), BNN6 can be decomposed by lignin within micellar nanoparticles via a photoinduced electron transfer mechanism in the aqueous medium. Lignin not only served as a sustainable carrier, enhancing the water dispersity of BNN6, but also acted as a biocompatible photosensitizer, triggering BNN6 decomposition with the concomitant release of NO. As a result, the micellar nanoparticles displayed superior antibacterial effects against Gram-negative and Gram-positive bacteria upon visible light illumination. Moreover, MTT assay revealed the negligible cytotoxic effect of the micellar nanoparticles to the mouse fibroblast cells (L929). This research provides more insight into the BNN6 decomposition mechanism and demonstrates a straightforward, effective, and biocompatible strategy for controlled NO-mediated antibacterial applications.
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Antibacterianos , Luz , Lignina , Nanopartículas , Óxido Nítrico , Antibacterianos/farmacología , Antibacterianos/química , Óxido Nítrico/química , Lignina/química , Lignina/farmacología , Ratones , Animales , Nanopartículas/química , Micelas , Donantes de Óxido Nítrico/química , Donantes de Óxido Nítrico/farmacología , Polietilenglicoles/químicaRESUMEN
Antibiotic resistance and the rise of untreatable bacterial infections pose severe threats to human health. Silver nanoparticles (AgNPs) have emerged as a promising antibacterial solution due to their broad-spectrum effectiveness. However, their relatively high cytotoxicity has limited their widespread application. In this study, ferulic acid (FA) was used as a reducing agent, while silver oxide served as a silver precursor to rapidly prepare FA-derived lignin (FAL) coated AgNPs (AgNPs@FAL) with a size ranging from 34.8 to 77.1 nm. Density functional theory (DFT) calculations indicated that the coating of FAL endowed AgNPs@FAL with high stability, preventing the oxidation of AgNPs prior to antibacterial applications. Cell experiments further indicated that AgNPs@FAL exhibited lower cell toxicity (â¼80 % viability of normal kidney cells cultured at 25 µg/mL AgNPs@FAL) compared to fully exposed commercially available citrate-modified AgNPs (AgNPs@CA). Antibacterial experiments revealed that the minimum inhibitory concentrations (MIC) of AgNPs@FAL against E. coli and S. aureus were 12.5 µg/mL and 25 µg/mL, respectively, surpassing the antibacterial effect of AgNPs@CA, as well as ampicillin and penicillin. Additionally, AgNPs@FAL was capable of disrupting E. coli and S. aureus biofilm formation. This novel AgNPs@FAL formulation presents a promising antibacterial solution, addressing limitations observed in conventional drugs.
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Antibacterianos , Ácidos Cumáricos , Escherichia coli , Lignina , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Plata , Plata/química , Plata/farmacología , Nanopartículas del Metal/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacología , Lignina/química , Lignina/farmacología , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Humanos , Biopelículas/efectos de los fármacos , Supervivencia Celular/efectos de los fármacosRESUMEN
The emergence of antibiotic-resistant bacteria necessitates the development of novel, sustainable, and biocompatible antibacterial agents. This study addresses cytotoxicity and environmental concerns associated with traditional silver nanoparticles (AgNPs) by exploring lignin, a readily available and renewable biopolymer, as a platform for AgNPs. We present a novel one-pot synthesis method for lignin-based AgNPs (AgNPs@AL) nanocomposites, achieving rapid synthesis within 5 min. This method utilizes various organic solvents, demonstrating remarkable adaptability to a wide range of lignin-dissolving systems. Characterization reveals uniform AgNP size distribution and morphology influenced by the chosen solvent. This adaptability suggests the potential for incorporating lignin-loaded antibacterial drugs alongside AgNPs, enabling combined therapy in a single nanocomposite. Antibacterial assays demonstrate exceptional efficacy against both Gram-negative and Gram-positive bacteria, with gamma-valerolactone (GVL)-assisted synthesized AgNPs exhibiting the most potent effect. Mechanistic studies suggest a combination of factors contributes to the antibacterial activity, including direct membrane damage caused by AgNPs and sustained silver ion release, ultimately leading to bacterial cell death. This work presents a straightforward, adaptable, and rapid approach for synthesizing biocompatible AgNPs@AL nanocomposites with outstanding antibacterial activity. These findings offer a promising and sustainable alternative to traditional antibiotics, contributing to the fight against antibiotic resistance while minimizing environmental impact.
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Introduction: Osteoporosis is a prevalent challenge in clinical orthopedics, affecting a significant percentage of individuals aged 50 and above. The goal of this study was to comprehensively understand the relationships between a specialized dietary regimen and the risk of developing osteoporosis. Methods: This study employed extensive genome-wide association study (GWAS) summary statistics derived from the UK Biobank. It encompassed 8 kinds of special diets and 7 datasets pertaining to osteoporosis and associated symptoms. The principal analytical approach employed was the inverse-variance weighted method. Additionally, sensitivity analysis was employed to elucidate the diverse multiplicity patterns observed in the final model. Results: Our results showed that there is significant evidence that a gluten-free diet is associated with osteoporosis [odds ratio (OR): 1.080, 95% confidence interval (CI): 1.048-1.112, p = 4.23E-07)]. Furthermore, there exists a suggestive link between the three distinct dietary approaches and osteoporosis [(OR: 0.949, 95%CI: 0.929-0.970, p = 3.00E-06) for comprehensive consumption; (OR: 1.053, 95%CI: 1.018-1.089, p = 2.23E-03) for abstaining from wheat consumption; (OR: 1.036, 95%CI: 1.005-1.068, p = 1.97E-02) for abstaining from sugar consumption]. No additional correlation between the special dietary regimens and osteoporosis has been observed. Conclusion: Our research has uncovered a notable correlation between a gluten-free diet and the occurrence of osteoporosis. Furthermore, it exerts a promoting influence on the onset of osteoporosis, which stands in direct contradiction to the therapeutic principles for Celiac Disease's complications. As such, a novel association among these three elements is postulated.
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Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Osteoporosis , Humanos , Osteoporosis/epidemiología , Reino Unido/epidemiología , Incidencia , Femenino , Masculino , Persona de Mediana Edad , Dieta Sin Gluten/estadística & datos numéricos , Factores de Riesgo , Anciano , Dieta/estadística & datos numéricosRESUMEN
Ligand-receptor recognition serves as the fundamental driving force for active targeting, yet it is still constrained by off-target effects. Herein, we demonstrate that circumventing or blocking the mononuclear phagocyte system (MPS) are both viable strategies to address off-target effects. Naturally derived lignin nanoparticles (LNPs) show great potential to block MPS due to its good stability, low toxicity, and degradability. We further demonstrate the impact of LNPs dosage on in vivo tumor targeting and antitumor efficacy. Our results show that a high dose of LNPs (300 mg/kg) leads to significant accumulation at the tumor site for a duration of 14 days after intravenous administration. In contrast, the low-dose counterparts (e.g., 50, 150 mg/kg) result in almost all LNPs accumulating in the liver. This discovery indicates that the liver is the primary site of LNP capture, leaving only the surplus LNPs the chance to reach the tumor. In addition, although cell membrane-engineered LNPs can rapidly penetrate tumors, they are still prone to capture by the liver during subsequent circulation in the bloodstream. Excitingly, comparable therapeutic efficacy is obtained for the above two strategies. Our findings may offer valuable insights into the targeted delivery of drugs for disease treatment.
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Macrófagos del Hígado , Lignina , Hígado , Nanopartículas , Fagocitosis , Animales , Lignina/farmacología , Lignina/química , Nanopartículas/química , Macrófagos del Hígado/efectos de los fármacos , Macrófagos del Hígado/metabolismo , Ratones , Hígado/metabolismo , Hígado/efectos de los fármacos , Hígado/patología , Fagocitosis/efectos de los fármacos , Humanos , Línea Celular Tumoral , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/patologíaRESUMEN
This study employs a combined computational and experimental approach to elucidate the mechanisms governing the interaction between lignin and urea, impacting lignin dissolution and subsequent aggregation behavior. Molecular dynamics (MD) simulations reveal how the urea concentration and temperature influence lignin conformation and interactions. Higher urea concentrations and temperatures promote lignin dispersion by disrupting intramolecular interactions and enhancing solvation. Density functional theory (DFT) calculations quantitatively assess the interaction energy between lignin and urea, supporting the findings from MD simulations. Anti-solvent precipitation demonstrates that increasing the urea concentration hinders the self-assembly of lignin nanoclusters. The findings provide valuable insights for optimizing lignin biorefinery processes by tailoring the urea concentration and temperature for efficient extraction and dispersion. Understanding the influence of urea on lignin behavior opens up avenues for designing novel lignin-based materials with tailored properties. This study highlights the potential for the synergetic application of MD simulations and DFT calculations to unravel complex material interactions at the atomic level.
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Zinc sulfide is a promising high-capacity anode for practical sodium-ion batteries, considering its high capacity and the low cost of zinc and sulfur sources. However, the pulverization of particulate zinc sulfide causes active mass collapse and penetration-induced short circuits of batteries. Herein, a zinc sulfide encapsulated in a nitrogen-doped carbon shell (ZnS@NC) was developed for high-performance anodes. The confinement effect of nitrogen-doped carbon stabilizes the active mass structure during cycling thanks to the robust chemically and electronically bonded connections between nitrogen-doped carbon and zinc sulfide nanoparticles. Furthermore, the cycling stability of the ZnS@NC anode is boosted by the robust inorganic-rich solid electrolyte interphase (SEI) formed in cyclic and linear ether-based electrolytes. The ZnS@NC anode displayed a reversible specific capacity of 584 mAh g-1, an excellent rate capability of 327 mAh g-1 at 70 A g-1, and a highly stable cycling performance over 10000 cycles. This work provides a practical and promising approach to designing stable conversion anodes for high-performance sodium-ion batteries.
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Of the 15 eligible studies identified via electronic searches in MEDLINE, EMBASE and CENTRAL in November 2022 for methotrexate therapy of moderate-to-severe atopic dermatitis, 12 were non-randomized controlled trial (non-RCT) studies with data from 437 patients (235 adults and 202 children). The response rates for short-term therapy were 77% [95% CI 55-99] (four studies; adults) - comparable to 81% [54-100] of RCTs (two studies; adults) (p = 0.63) - and 61% [43-79] (two studies; children), and for medium/long-term therapy were 88.9% [74.3-100.0] (four studies; adults) and 77.7% [61.5-94.0] (three studies; children). Children had a markedly lower rate of treatment discontinuation due to side effects [2.0% (five studies; children) vs. 14.9% (six studies; adults)], but were more likely to experience gastrointestinal disorders {relative risk (RR) 2.0 [1.44-2.71]}, fatigue (RR 2.3 [1.35-3.72]), headache (RR 2.8 [1.23-5.61]), and infections (RR 2.9 [2.18-3.58]). Other adverse events (children vs. adults) included hepatic disorders (32/176 vs. 35/305) and blood and lymphatic system/bone marrow disorders (25/148 vs. 19/184). Four serious adverse events were reported (children). Evidence from daily practice was limited by bias in the selection of participants in the study.
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Dermatitis Atópica , Adulto , Niño , Humanos , Dermatitis Atópica/tratamiento farmacológico , Metotrexato/efectos adversos , Ensayos Clínicos Controlados no Aleatorios como AsuntoRESUMEN
BACKGROUND: Anti-melanoma differentiation-associated gene 5 antibody-positive (anti-MDA5 Ab+) dermatomyositis complicated with rapidly progressive interstitial lung disease (anti-MDA5 Ab+ DM-RP-ILD) has an unclear underlying mechanism with no recommended unified treatment plan. Herein, one of the cases that we report (Case 2) was successfully treated with tocilizumab despite having lung infection. CASE SUMMARY: Case 1 was a 30-year-old woman who was admitted due to recurrent rash for 5 mo, fever and cough for 1 mo, and chest tightness for 3 d. She was diagnosed with non-myopathic dermatomyositis (anti-MDA5 Ab+) and interstitial pneumonia, and was treated with the combination of hormone therapy and cyclophosphamide followed by oral tacrolimus. Case 2 was a 31-year-old man admitted due to systemic rash accompanied by muscle weakness of limbs for more than 1 mo, and chest tightness and dry cough for 4 d. He was diagnosed with dermatomyositis (anti-MDA5 Ab+) and acute interstitial pneumonia with Pneumocystis jirovecii and Aspergillus fumigatus infections and was treated with hormone therapy (without cyclophosphamide) and the combination of tocilizumab and tacrolimus. The condition of both patients eventually improved and they were discharged and showed clinically stable condition at the latest follow-up. CONCLUSION: Tocilizumab could be a salvage treatment for patients with anti-MDA5 Ab+ DM-RP-ILD who are refractory to intensive immunosuppression.
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Co-based catalysts play a crucial role in the activation of peroxymonosulfate (PMS) for degradation contaminants. However, the practical application of such catalysts is hindered by challenges like the self-aggregation of Co nanoparticles and leaching of Co2+. In this study, the Co-based catalyst Co-N/C@CL was synthesized from carboxymethylated lignin obtained by grafting abundant carboxymethyl groups into alkali lignin, in which the presence of these carboxymethyl groups enhanced its water solubility and allowed the formation of stable macromolecular complexes with Co2+. This catalyst exhibited a high specific surface area (521.8 m2·g-1) and a uniform distribution of Co nanoparticles. Consequently, the Co-N/C@CL/PMS system could completely remove 20 ppm tetracycline (TC) in 2 min at a rate of 2.404 min-1. Experimental results and DFT calculations revealed that the synergistic effect of lignin carbon and Co NPs accelerated the cleavage and electron transfer of OO bonds, thus promoting the formation of 1O2, OH and SO4-, with 1O2 emerging as the predominant contributor. Moreover, Co-N/C@CL displayed excellent cycling stability and low Co2+ leaching. This work not only provides a feasible strategy for the preparation of highly active and stable Co-based carbon materials but also offers a promising catalyst for the efficient degradation of TC.
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Antibacterianos , Lignina , Tetraciclina , Carbono , NitrógenoRESUMEN
Lignin is the most abundant natural phenolic polymer. However, the severe condensations of industrial lignin resulted in an undesirable apparent morphology and darker color, which hindered its application in the field of daily chemicals. Therefore, a ternary deep eutectic solvent is used to obtain lignin with light-color and low condensations from softwood. The results showed that the brightness value of lignin extracted from aluminum chloride-1,4-butanediol-choline chloride at 100 °C and 1.0 h was 77.9, and the lignin yield was 32.2 ± 0.6%. It is important that 95.8% of ß-O-4 linkages (ß-O-4 and ß-O-4') was retained. Lignin is used to prepare sunscreens and is added to physical sunscreens at 5%, with SPF up to 26.95 ± 4.20. Meanwhile, enzyme hydrolysis experiments and reaction liquid composition tests were also conducted. In conclusion, a systematic understanding of this efficient process could facilitate high-value utilization of lignocellulosic biomass in industrial processes.
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Disolventes Eutécticos Profundos , Lignina , Lignina/química , Ácidos de Lewis , Solventes/química , Protectores Solares , Biomasa , HidrólisisRESUMEN
Rational design of efficient, stable, and inexpensive bifunctional electrocatalysts for oxygen evolution reactions (OER) and hydrogen evolution reactions (HER) is a key challenge to realize green hydrogen production via electrolytic water splitting. Herein, Ru nanoparticles and FeNi alloy heterojunction catalyst (Ru-FeNi@NLC) encapsulated via lignin-derived carbon was prepared by self-assembly precipitation and in situ pyrolysis. The designed catalyst displays excellent performance at 10â mA cm-2 with low overpotentials of 36â mV for HER and 198â mV for OER, and only needs 1.48â V for overall water splitting. Results and DFT calculations show the unique N-doped lignin-derived carbon layer and Ru-FeNi heterojunction contribute to optimized electronic structure for enhancing electron transfer, balanced free energy of reactants and intermediates in the sorption/desorption process, and significantly reduced reaction energy barrier for the HER and OER rate-determining steps, thus improved reaction kinetics. This work provides a new in situ pyrolysis doping strategy based on renewable biomass for the construction of highly active, stable and cost-effective catalysts.
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This paper proposes a novel trajectory planning algorithm to design an end-effector motion profile along a specified path. An optimization model based on the whale optimization algorithm (WOA) is established for time-optimal asymmetrical S-curve velocity scheduling. Trajectories designed by end-effector limits may violate kinematic constraints due to the non-linear relationship between the operation and joint space of redundant manipulators. A constraints conversion approach is proposed to update end-effector limits. The path can be divided into segments at the minimum of the updated limitations. On each path segment, the jerk-limited S-shaped velocity profile is generated within the updated limitations. The proposed method aims to generate end-effector trajectory by kinematic constraints which are imposed on joints, resulting in efficient robot motion performance. The WOA-based asymmetrical S-curve velocity scheduling algorithm can be automatically adjusted for different path lengths and start/end velocities, allowing flexibility in finding the time-optimal solution under complex constraints. Simulations and experiments on a redundant manipulator prove the effect and superiority of the proposed method.
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Electrochemical oxidative lignin cleavage and coupled 2-furaldehyde reduction provide a promising approach for producing high-value added products. However, developing efficient bifunctional electrocatalysts with noble-metal-like activity still remains a challenge. Here, an efficient electrochemical strategy is reported for the selective oxidative cleavage of Cα -Cß bonds in lignin into aromatic monomers by tailoring the electronic structure through P-doped CoMoO4 spinels (99% conversion, highest monomer selectivity of 56%). Additionally, the conversion and selectivity of 2-furaldehyde reduction to 2-methyl furan reach 87% and 73%, respectively. In situ Fourier transform infrared and density functional theory analysis reveal that an upward shift of the Ed upon P-doping leads to an increase in the antibonding level, which facilitates the Cα -Cß adsorption of the lignin model compounds, thereby enhancing the bifunctional electrocatalytic activity of the active site. This work explores the potential of a spinel as a bifunctional electrocatalyst for the oxidative cracking of lignin and the reductive conversion of small organic molecules to high-value added chemicals via P-anion modulation.
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Amorphous carbons are promising anodes for high-rate potassium-ion batteries. Most low-temperature annealed amorphous carbons display unsatisfactory capacities. Heteroatom-induced defect engineering of amorphous carbons could enhance their reversible capacities. Nevertheless, most lignocellulose biomasses lack heteroatoms, making it a challenge to design highly heteroatom-doped carbons (> 10 at%). Herein, we report a new preparation strategy for amorphous carbon anodes. Nitrogen/sulfur co-doped lignin-derived porous carbons (NSLPC) with ultra-high nitrogen doping levels (21.6 at% of N and 0.8 at% of S) from renewable lignin biomacromolecule precursors were prepared through a supramolecule-mediated pyrolysis strategy. This supermolecule/lignin composite decomposes forming a covalently bonded graphitic carbon/amorphous carbon intermediate product, which induces the formation of high heteroatom doping in the obtained NSLPC. This unique pyrolysis chemistry and high heteroatom doping of NSLPC enable abundant defective active sites for the adsorption of K+ and improved kinetics. The NSLPC anode delivered a high reversible capacity of 419 mAh gâ1 and superior cycling stability (capacity retention of 96.6% at 1 A gâ1 for 1000 cycles). Potassium-ion hybrid capacitors assembled by NSLPC anode exhibited excellent cycling stability (91% capacity retention for 2000 cycles) and a high energy density of 71 Wh kg-1 at a power density of 92 W kg-1.
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This study is concerned with the adaptive neural network (NN) observer design problem for continuous-time switched systems via quantized output signals. A novel NN observer is presented in which the adaptive laws are constructed using quantized measurements. Then, persistent dwell time (PDT) switching is considered in the observer design to describe fast and slow switching in a unified framework. Accurate estimations of state and actuator efficiency factor can be obtained by the proposed observer technique despite actuator degradation. Finally, a simulation example is provided to illustrate the effectiveness of the developed NN observer design approach.
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This article investigates the fault estimation (FE) problem for a class of nonlinear systems via an adaptive fuzzy approach. Considering the limited communication capacity of networks, the quantized measurement signals are used to construct adaptive laws instead of the real measurements in the designed fuzzy observer. By injecting the quantizer parameter into the observer inputs, the quantization effects on the convergence of estimation errors can be compensated. It is also shown that nondifferentiable actuator faults can be reconstructed by the developed FE approach. Finally, two simulation examples are provided to illustrate the validity of the presented scheme.
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This article addresses the simultaneous actuator and sensor fault estimation (FE) problem for a class of Markovian jump systems (MJSs) with nondifferentiable actuator failures. In order to overcome the difficulties brought by the nondifferentiable actuator failures, we construct an extended vector composed of states, sensor faults, and disturbances, where the derivatives of actuator failures are not required in this augmented system. Then, two novel observer-based approaches are developed for the augmented descriptor system to cope with the FE problem. The first one is a reduced-order FE observer, where the actuator failures can be estimated by the algebraic input reconstruction strategy. The second one refers to an iterative learning observer (ILO) design method, which can obtain the accurate FE result by integrating the estimations in the iterative processes. The two proposed FE observer design methods can avoid the sliding surface switching problem produced by sliding-mode observers in the area of MJSs. Finally, a practical example of the F-404 aircraft engine system is presented to show the validity of the proposed FE observer design techniques.
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The solar X-ray and Extreme Ultraviolet Imager (X-EUVI), developed by the Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences (CIOMP), is the first space-based solar X-ray and Extreme ultraviolet (EUV) imager of China loaded on the Fengyun-3E (FY-3E) satellite supported by the China Meteorological Administration (CMA) for solar observation. Since started work on July 11, 2021, X-EUVI has obtained many solar images. The instrument employs an innovative dual-band design to monitor a much larger temperature range on the Sun, which covers 0.6-8.0 nm in the X-ray region with six channels and 19.5 nm in the EUV region. X-EUVI has a field of view of 42', an angular resolution of 2.5â³ per pixel in the EUV band and an angular resolution of 4.1â³ per pixel in the X-ray band. The instrument also includes an X-ray and EUV irradiance sensor (X-EUVS) with the same bands as its imaging optics, which measures the solar irradiance and regularly calibrates the solar images. The radiometric calibration of X-EUVS on the ground has been completed, with a calibration accuracy of 12%. X-EUVI is loaded on the FY-3E satellite and rotates relative to the Sun at a uniform rate. Flat-field calibration is conducted by utilizing successive rotation solar images. The agreement between preliminarily processed X-EUVI images and SDO/AIA and Hinode/XRT images indicates that X-EUVI and the data processing algorithm operate properly and that the data from X-EUVI can be applied to the space weather forecast system of CMA and scientific investigations on solar activity.