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1.
Nature ; 618(7965): 494-499, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37198493

RESUMEN

Hydrodynamics accurately describe relativistic heavy-ion collision experiments well before local thermal equilibrium is established1. This unexpectedly rapid onset of hydrodynamics-which takes place on the fastest available timescale-is called hydrodynamization2-4. It occurs when an interacting quantum system is quenched with an energy density that is much greater than its ground-state energy density5,6. During hydrodynamization, energy gets redistributed across very different energy scales. Hydrodynamization precedes local equilibration among momentum modes5, which is local prethermalization to a generalized Gibbs ensemble7,8 in nearly integrable systems or local thermalization in non-integrable systems9. Although many theories of quantum dynamics postulate local prethermalization10,11, the associated timescale has not been studied experimentally. Here we use an array of one-dimensional Bose gases to directly observe both hydrodynamization and local prethermalization. After we apply a Bragg scattering pulse, hydrodynamization is evident in the fast redistribution of energy among distant momentum modes, which occurs on timescales associated with the Bragg peak energies. Local prethermalization can be seen in the slower redistribution of occupation among nearby momentum modes. We find that the timescale for local prethermalization in our system is inversely proportional to the momenta involved. During hydrodynamization and local prethermalization, existing theories cannot quantitatively model our experiment. Exact theoretical calculations in the Tonks-Girardeau limit12 show qualitatively similar features.

2.
Small ; 20(13): e2304150, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37964398

RESUMEN

Rheumatoid arthritis (RA), a systemic autoimmune disease, poses a significant human health threat. Iguratimod (IGUR), a novel disease-modifying antirheumatic drug (DMARD), has attracted great attention for RA treatment. Due to IGUR's hydrophobic nature, there's a pressing need for effective pharmaceutical formulations to enhance bioavailability and therapeutic efficacy. The high-gravity nanoprecipitation technique (HGNPT) emerges as a promising approach for formulating poorly water-soluble drugs. In this study, IGUR nanodrugs (NanoIGUR) are synthesized using HGNPT, with a focus on optimizing various operational parameters. The outcomes revealed that HGNPT enabled the continuous production of NanoIGUR with smaller sizes (ranging from 300 to 1000 nm), more uniform shapes, and reduced crystallinity. In vitro drug release tests demonstrated improved dissolution rates with decreasing particle size and crystallinity. Notably, in vitro and in vivo investigations showcased NanoIGUR's efficacy in inhibiting synovial fibroblast proliferation, migration, and invasion, as well as reducing inflammation in collagen-induced arthritis. This study introduces a promising strategy to enhance and broaden the application of poorly water-soluble drugs.


Asunto(s)
Antirreumáticos , Artritis Reumatoide , Cromonas , Nanopartículas , Sulfonamidas , Humanos , Alcohol Polivinílico , Artritis Reumatoide/tratamiento farmacológico , Antirreumáticos/química , Antirreumáticos/farmacología , Antirreumáticos/uso terapéutico , Agua
3.
Magn Reson Med ; 91(5): 1923-1935, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38098427

RESUMEN

PURPOSE: To demonstrate a novel MR elastography (MRE) technique, termed here wavelet MRE. With this technique, broadband motion sensitivity is achievable. Moreover, the true tissue displacement can be reconstructed with a simple inverse transform. METHODS: A wavelet MRE sequence was developed with motion-encoding gradients based on Haar wavelets. From the phase images' displacement was estimated using an inverse transform. Simulations were performed using a frequency sweep and a transient as ground-truth motions. A PVC phantom was scanned using wavelet MRE and standard MRE with both transient (one and 10 cycles of 90-Hz motion) and steady-state dual-frequency motion (30 and 60 Hz) for comparison. The technique was tested in a human brain, and motion trajectories were estimated for each voxel. RESULTS: In simulation, the displacement information estimated from wavelet MRE closely matched the true motion. In the phantom test, the MRE phase data generated from the displacement information derived from wavelet MRE agreed well with standard MRE data. Testing of wavelet MRE to assess transient motion waveforms in the brain was successful, and the tissue motion observed was consistent with a previous study. CONCLUSION: The uniform and broadband frequency response of wavelet MRE makes it a promising method for imaging transient, multifrequency motion, or motion with unknown frequency content. One potential application is measuring the response of brain tissue undergoing low-amplitude, transient vibrations as a model for the study of traumatic brain injury.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Diagnóstico por Imagen de Elasticidad/métodos , Algoritmos , Encéfalo/diagnóstico por imagen , Fantasmas de Imagen , Sonido
4.
Langmuir ; 40(17): 9134-9143, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38636482

RESUMEN

Wound healing has been a persistent clinical challenge for a long time. Electrical stimulation is an effective therapy with the potential to accelerate wound healing. In this work, the self-powered electrospun nanofiber membranes (triples) were constructed as multifunctional wound dressings with electrical stimulation and biochemical capabilities. Triple was composed of a hydrolyzable inner layer with antiseptic and hemostatic chitosan, a hydrophilic core layer loaded with conductive AgNWs, and a hydrophobic outer layer fabricated by self-powered PVDF. Triple exhibited presentable wettability and acceptable moisture permeability. Electrical performance tests indicated that triple can transmit electrical signals formed by the piezoelectric effect to the wound. High antibacterial activities were observed for triple against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, with inhibition rates of 96.52, 98.63, and 97.26%, respectively. In vitro cell assays demonstrated that triple cells showed satisfactory proliferation and mobility. A whole blood clotting test showed that triple can enhance hemostasis. The innovative self-powered multifunctional fibers presented in this work offer a promising approach to addressing complications and expediting the promotion of chronic wound healing.


Asunto(s)
Antibacterianos , Escherichia coli , Nanofibras , Pseudomonas aeruginosa , Staphylococcus aureus , Cicatrización de Heridas , Cicatrización de Heridas/efectos de los fármacos , Nanofibras/química , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/química , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/fisiología , Quitosano/química , Humanos , Animales , Proliferación Celular/efectos de los fármacos
6.
Nutr J ; 23(1): 79, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39020341

RESUMEN

BACKGROUND: Previous studies have shown that high-density lipoprotein cholesterol (HDL-C) levels are positively associated with cognitive function across a range of concentrations. However, recent studies have suggested that very high HDL-C levels may lead to poorer outcomes. Therefore, we aimed to investigate the relationship between different concentrations of HDL-C and cognitive impairment risk. METHODS: We collected data from 3632 participants aged over 60 years from the U.S. National Health and Nutrition Examination Survey (NHANES) between 2011 and 2014 to assess the relationship between HDL-C and cognitive function. Cognitive function was evaluated with the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) test, the animal fluency test (AFT), and the digit symbol substitution test (DSST). We used restricted cubic spline models and logistic regression to examine the association between HDL-C and cognitive function. RESULTS: A U-shaped was observed between HDL-C and cognitive outcomes, individuals with higher risk in those with both low and very high HDL-C levels compared with those with midrange values. Very high HDL-C levels (≥ 2.50 mmol/L) were associated with increased risk of cognitive impairment (OR = 2.19; 95% CI, 1.12-4.28) compared with those with HDL-C levels in the range of 1.50 to 1.99 mmol/L in older adults after adjustment for confounding factors. Interaction test demonstrated that relationship between very high HDL-C and the risk of cognitive impairment was not changed in different sex and race group (P for interaction > 0.05). CONCLUSIONS: Very high HDL-C levels were associated with an increased risk of cognitive impairment. HDL-C may not be a protective factor for maintaining brain health in older adults at very high levels.


Asunto(s)
HDL-Colesterol , Disfunción Cognitiva , Encuestas Nutricionales , Humanos , HDL-Colesterol/sangre , Masculino , Femenino , Anciano , Disfunción Cognitiva/sangre , Disfunción Cognitiva/epidemiología , Encuestas Nutricionales/estadística & datos numéricos , Encuestas Nutricionales/métodos , Factores de Riesgo , Persona de Mediana Edad , Cognición/fisiología , Estudios Transversales , Estados Unidos/epidemiología , Anciano de 80 o más Años
7.
Arch Toxicol ; 98(6): 1919-1935, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38584193

RESUMEN

Human liver-derived metabolically competent HepaRG cells have been successfully employed in both two-dimensional (2D) and 3D spheroid formats for performing the comet assay and micronucleus (MN) assay. In the present study, we have investigated expanding the genotoxicity endpoints evaluated in HepaRG cells by detecting mutagenesis using two error-corrected next generation sequencing (ecNGS) technologies, Duplex Sequencing (DS) and High-Fidelity (HiFi) Sequencing. Both HepaRG 2D cells and 3D spheroids were exposed for 72 h to N-nitrosodimethylamine (NDMA), followed by an additional incubation for the fixation of induced mutations. NDMA-induced DNA damage, chromosomal damage, and mutagenesis were determined using the comet assay, MN assay, and ecNGS, respectively. The 72-h treatment with NDMA resulted in concentration-dependent increases in cytotoxicity, DNA damage, MN formation, and mutation frequency in both 2D and 3D cultures, with greater responses observed in the 3D spheroids compared to 2D cells. The mutational spectrum analysis showed that NDMA induced predominantly A:T → G:C transitions, along with a lower frequency of G:C → A:T transitions, and exhibited a different trinucleotide signature relative to the negative control. These results demonstrate that the HepaRG 2D cells and 3D spheroid models can be used for mutagenesis assessment using both DS and HiFi Sequencing, with the caveat that severe cytotoxic concentrations should be avoided when conducting DS. With further validation, the HepaRG 2D/3D system may become a powerful human-based metabolically competent platform for genotoxicity testing.


Asunto(s)
Ensayo Cometa , Daño del ADN , Dimetilnitrosamina , Secuenciación de Nucleótidos de Alto Rendimiento , Pruebas de Micronúcleos , Mutágenos , Humanos , Dimetilnitrosamina/toxicidad , Ensayo Cometa/métodos , Pruebas de Micronúcleos/métodos , Mutágenos/toxicidad , Daño del ADN/efectos de los fármacos , Esferoides Celulares/efectos de los fármacos , Pruebas de Mutagenicidad/métodos , Técnicas de Cultivo de Célula , Línea Celular , Hepatocitos/efectos de los fármacos , Mutagénesis/efectos de los fármacos , Mutación , Relación Dosis-Respuesta a Droga
8.
Langmuir ; 39(37): 13109-13120, 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37672621

RESUMEN

Controlled pesticide delivery systems offer many distinctive advantages over conventional pesticide formulations. In this work, degradable poly(N-isopropylacrylamide) (PNIPAM)-tannic acid (TA) microgels and multifunctional PDA@PNIPAM-TA nanocomposites were prepared in a high-gravity rotating packed bed reactor (RPB) for smart pesticide delivery and release. The as-prepared microgels and nanocomposites showed reversible temperature-dependent swelling/deswelling behavior and irreversible pH-induced degradation. A dynamic contact angle test suggested that the introduction of TA and PDA into the PNIPAM matrix could enhance foliar adhesion and deposition efficiency. The nanocomposites were further used for the encapsulation and delivery of imidacloprid (IMI) to protect it from rapid photolysis and improve its pest-control efficiency. Their thermoresponsive behavior as well as pesticide loading capacity could be tuned by tailoring the PNIPAM-TA shell thickness, which could be varied by the NIPAM amount. The release rate of IMI from the core/shell nanocomposites was positively correlated with environmental temperature and near-infrared (NIR) light, which was adaptive to the positive temperature-dependent toxicity correlation of IMI and the increasing trend of pests under high temperature. The cumulative release of IMI was 23.5% at 25 °C, while it was 81.2% at 40 °C after 24 h of incubation, and the release rate was greatly enhanced under NIR irradiation. The results indicated that the facile control of pesticide release could be realized by regulating environmental conditions. This work also provides an idea for using high-gravity technology to conveniently construct a smart, effective, and environmentally friendly pesticide delivery system for sustainable crop protection.

9.
Bioorg Chem ; 138: 106619, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37253310

RESUMEN

Three new diterpenoids with an unusual carbon skeleton, pedilanins A-C (1-3), and nine new jatrophane diterpenoids, pedilanins D-L (4-12), along with five known ones (13-17), were isolated from Pedilanthus tithymaloides. Compounds 1-3 characterize an unprecedented tricyclo[10.3.0.02,9]pentadecane skeleton. Compounds 4-8 are rare examples of the jatrophanes bearing a cyclic hemiketal substructure. Their structures were determined by an extensive analysis of HRESIMS, NMR, quantum-chemical calculation, DP4+ probability, and X-ray crystallographic data. In the bioassay, compounds 1-12 dramatically reversed multidrug resistance in cancer cells with the fold-reversals ranging from 17.9 to 396.8 at the noncytotoxic concentration of 10 µM. The mechanism results indicated that compounds 2 and 3 inhibited the P-glycoprotein (Pgp) transporter function, thus reversing the drug resistance.


Asunto(s)
Diterpenos , Euphorbia , Estructura Molecular , Euphorbia/química , Resistencia a Múltiples Medicamentos , Radiofármacos/farmacología , Diterpenos/farmacología , Diterpenos/química
10.
Arch Toxicol ; 97(4): 1163-1175, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36847820

RESUMEN

The in vitro micronucleus (MN) assay is a component of most test batteries used in assessing potential genotoxicity. Our previous study adapted metabolically competent HepaRG cells to the high-throughput (HT) flow-cytometry-based MN assay for genotoxicity assessment (Guo et al. in J Toxicol Environ Health A 83:702-717, 2020b, https://doi.org/10.1080/15287394.2020.1822972 ). We also demonstrated that, compared to HepaRG cells grown as two-dimensional (2D) cultures, 3D HepaRG spheroids have increased metabolic capacity and improved sensitivity in detecting DNA damage induced by genotoxicants using the comet assay (Seo et al. in ALTEX 39:583-604, 2022, https://doi.org/10.14573/altex.22011212022 ). In the present study, we have compared the performance of the HT flow-cytometry-based MN assay in HepaRG spheroids and 2D HepaRG cells by testing 34 compounds, including 19 genotoxicants or carcinogens and 15 compounds that show different genotoxic responses in vitro and in vivo. 2D HepaRG cells and spheroids were exposed to the test compounds for 24 h, followed by an additional 3- or 6-day incubation with human epidermal growth factor to stimulate cell division. The results demonstrated that HepaRG spheroids showed generally higher sensitivity in detecting several indirect-acting genotoxicants (require metabolic activation) compared to 2D cultures, with 7,12-dimethylbenzanthracene and N-nitrosodimethylamine inducing higher % MN formation along with having significantly lower benchmark dose values for MN induction in 3D spheroids. These data suggest that 3D HepaRG spheroids can be adapted to the HT flow-cytometry-based MN assay for genotoxicity testing. Our findings also indicate that integration of the MN and comet assays improved the sensitivity for detecting genotoxicants that require metabolic activation. These results suggest that HepaRG spheroids may contribute to New Approach Methodologies for genotoxicity assessment.


Asunto(s)
Daño del ADN , Mutágenos , Humanos , Pruebas de Micronúcleos/métodos , Mutágenos/toxicidad , Ensayo Cometa/métodos , Pruebas de Mutagenicidad/métodos
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