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1.
Fitoterapia ; 177: 106079, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38897252

RESUMEN

This study aims to elucidate the potential targets and molecular mechanisms underlying the anticancer effects of Red fermented rice extract using molecular simulation techniques. The inhibitory effects of different elution fractions of Red fermented rice extract on A549 and MCF-7 cell proliferation were evaluated through CCK-8 assays. Liquid chromatography-mass spectrometry (LC-MS) was employed to elucidate the structural information of active components, while molecular simulation techniques aided in identifying target proteins based on small molecule structures. Protein immunoblotting was utilized to investigate the mechanisms of action of relevant targets. The study found that the petroleum ether-ethyl acetate and ethyl acetate elution fractions of Red fermented rice extract significantly inhibited A549 and MCF-7 cell proliferation, with stronger effects observed on A549 cells. LC-MS structural analysis identified 25 small molecule structures. Molecular simulations successfully revealed interaction between active elution fractions of Red fermented rice extract and the cancer-related protein FGFR1. Further investigation into the phosphorylation of FGFR1 and its downstream pathway targets PI3K/AKT demonstrated that the active elution fractions exerted their anticancer activity by inhibiting the phosphorylation of FGFR1, PI3K, and AKT proteins. This comprehensive study, integrating CCK-8 assays, LC-MS, molecular simulation techniques, and protein immunoblotting, provides a deep understanding of the anticancer mechanisms of Red fermented rice extract, guiding its further development and clinical application.

2.
Sci Robot ; 9(91): eadl2007, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38924422

RESUMEN

Cytokines have been identified as key contributors to the development of inflammatory bowel disease (IBD), yet conventional treatments often prove inadequate and carry substantial side effects. Here, we present an innovative biohybrid robotic system, termed "algae-MΦNP-robot," for addressing IBD by actively neutralizing colonic cytokine levels. Our approach combines moving green microalgae with macrophage membrane-coated nanoparticles (MΦNPs) to efficiently capture proinflammatory cytokines "on the fly." The dynamic algae-MΦNP-robots outperformed static counterparts by enhancing cytokine removal through continuous movement, better distribution, and extended retention in the colon. This system is encapsulated in an oral capsule, which shields it from gastric acidity and ensures functionality upon reaching the targeted disease site. The resulting algae-MΦNP-robot capsule effectively regulated cytokine levels, facilitating the healing of damaged epithelial barriers. It showed markedly improved prevention and treatment efficacy in a mouse model of IBD and demonstrated an excellent biosafety profile. Overall, our biohybrid algae-MΦNP-robot system offers a promising and efficient solution for IBD, addressing cytokine-related inflammation effectively.


Asunto(s)
Colon , Citocinas , Enfermedades Inflamatorias del Intestino , Nanopartículas , Robótica , Animales , Citocinas/metabolismo , Enfermedades Inflamatorias del Intestino/metabolismo , Robótica/instrumentación , Ratones , Humanos , Macrófagos/metabolismo , Mucosa Intestinal/metabolismo , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Masculino , Diseño de Equipo , Epitelio
3.
Sci Adv ; 10(24): eadn6157, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38865468

RESUMEN

Lung metastasis poses a formidable challenge in the realm of cancer treatment, with conventional chemotherapy often falling short due to limited targeting and low accumulation in the lungs. Here, we show a microrobot approach using motile algae for localized delivery of drug-loaded nanoparticles to address lung metastasis challenges. The biohybrid microrobot [denoted "algae-NP(DOX)-robot"] combines green microalgae with red blood cell membrane-coated nanoparticles containing doxorubicin, a representative chemotherapeutic drug. Microalgae provide autonomous propulsion in the lungs, leveraging controlled drug release and enhanced drug dispersion to exert antimetastatic effects. Upon intratracheal administration, algae-NP(DOX)-robots efficiently transport their drug payload deep into the lungs while maintaining continuous motility. This strategy leads to rapid drug distribution, improved tissue accumulation, and prolonged retention compared to passive drug-loaded nanoparticles and free drug controls. In a melanoma lung metastasis model, algae-NP(DOX)-robots exhibit substantial improvement in therapeutic efficacy, reducing metastatic burden and extending survival compared to control groups.


Asunto(s)
Doxorrubicina , Neoplasias Pulmonares , Nanopartículas , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Animales , Doxorrubicina/farmacología , Doxorrubicina/química , Doxorrubicina/administración & dosificación , Nanopartículas/química , Ratones , Línea Celular Tumoral , Humanos , Sistemas de Liberación de Medicamentos , Microalgas , Robótica , Progresión de la Enfermedad , Antineoplásicos/farmacología , Antineoplásicos/administración & dosificación , Antineoplásicos/química
4.
ChemSusChem ; : e202400827, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38785150

RESUMEN

Ozonation water treatment technology has attracted increasing attention due to its environmental benign and high efficiency. Rutile PbO2 is a promising anode material for electrochemical ozone production (EOP). However, the reaction mechanism underlying ozone production catalyzed by PbO2 was rarely studied and not well-understood, which was in part due to the overlook of the electrochemistry-driven formation of oxygen vacancy (OV) of PbO2. Herein, we unrevealed the origin of the EOP activity of PbO2 starting from the electrochemical surface state analysis using density functional theory (DFT) calculations, activity analysis, and catalytic volcano modeling. Interestingly, we found that under experimental EOP potential (i.e., a potential around 2.2 V vs. reversible hydrogen electrode), OV can still be generated easily on PbO2 surfaces. Our subsequent kinetic and thermodynamic analyses show that these OV sites on PbO2 surfaces are highly active for the EOP reaction through an interesting atomic oxygen (O*)-O2 coupled mechanism. In particular, rutile PbO2(101) with the "in-situ" generated OV exhibited superior EOP activities, outperforming (111) and (110). Finally, by catalytic modeling, we found that PbO2 is close to the theoretical optimum of the reaction, suggesting a superior EOP performance of rutile PbO2. All these analyses are in good agreement with experimental observations.

5.
Fitoterapia ; 176: 106030, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38768795

RESUMEN

Four pairs of undescribed enantiomeric guaiane sesquiterpenoids, (±)-alismaenols A-D (1a/1b, 3a/3b-5a/5b), together with a pair of known ones (2a/2b) were isolated from the rhizomes of Alisma plantago-aquatica. The structures and relative configurations of the isolates were established by analysis of their 1D, 2D-NMR and HRESIMS data. Their absolute configurations were determined by comparison of their experimental CD spectra and calculated electronic circular dichroism (ECD) spectra or by single-crystal X-ray diffraction analysis. All compounds (1a/1b-5a/5b) were evaluated for their inhibitory effects on nitric oxide (NO) production in LPS-induced RAW 264.7 cells, and compound 1a exhibited stronger activity (IC50 = 12.89 µM) than indomethacin (IC50 = 14.03 µM).


Asunto(s)
Alisma , Óxido Nítrico , Fitoquímicos , Rizoma , Sesquiterpenos de Guayano , Rizoma/química , Ratones , Células RAW 264.7 , Estructura Molecular , Óxido Nítrico/metabolismo , Animales , Alisma/química , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Sesquiterpenos de Guayano/aislamiento & purificación , Sesquiterpenos de Guayano/farmacología , Sesquiterpenos de Guayano/química , China , Estereoisomerismo , Antiinflamatorios/farmacología , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/química
6.
Bioact Mater ; 38: 321-330, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38764446

RESUMEN

Given their dangerous effects on the nervous system, neurotoxins represent a significant threat to public health. Various therapeutic approaches, including chelating agents, receptor decoys, and toxin-neutralizing antibodies, have been explored. While prophylactic vaccines are desirable, it is oftentimes difficult to effectively balance their safety and efficacy given the highly dangerous nature of neurotoxins. To address this, we report here on a nanovaccine against neurotoxins that leverages the detoxifying properties of cell membrane-coated nanoparticles. A genetically modified cell line with constitutive overexpression of the α7 nicotinic acetylcholine receptor is developed as a membrane source to generate biomimetic nanoparticles that can effectively and irreversibly bind to α-bungarotoxin, a model neurotoxin. This abrogates the biological activity of the toxin, enabling the resulting nanotoxoid to be safely delivered into the body and processed by the immune system. When co-administered with an immunological adjuvant, a strong humoral response against α-bungarotoxin is generated that protects vaccinated mice against a lethal dose of the toxin. Overall, this work highlights the potential of using genetic modification strategies to develop nanotoxoid formulations against various biological threats.

7.
Biochem Pharmacol ; 224: 116220, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38641307

RESUMEN

Alpha-enolase (ENO1), a multifunctional protein with carcinogenic properties, has emerged as a promising cancer biomarker because of its differential expression in cancer and normal cells. On the basis of this characteristic, we designed a cell-targeting peptide that specifically targets ENO1 and connected it with the drug doxorubicin (DOX) by aldehyde-amine condensation. A surface plasmon resonance (SPR) assay showed that the affinity for ENO1 was stronger (KD = 2.5 µM) for the resulting cell-targeting drug, DOX-P, than for DOX. Moreover, DOX-P exhibited acid-responsive capabilities, enabling precise release at the tumor site under the guidance of the homing peptide and alleviating DOX-induced cardiotoxicity. An efficacy experiment confirmed that, the targeting ability of DOX-P toward ENO1 demonstrated superior antitumor activity against colorectal cancer than that of DOX, while reducing its toxicity to cardiomyocytes. Furthermore, in vivo metabolic distribution results indicated low accumulation of DOX-P in nontumor sites, further validating its targeting ability. These results showed that the ENO1-targeted DOX-P peptide has great potential for application in targeted drug-delivery systems for colorectal cancer therapy.


Asunto(s)
Antibióticos Antineoplásicos , Neoplasias Colorrectales , Doxorrubicina , Sistemas de Liberación de Medicamentos , Fosfopiruvato Hidratasa , Proteínas Supresoras de Tumor , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacología , Fosfopiruvato Hidratasa/metabolismo , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Animales , Proteínas Supresoras de Tumor/metabolismo , Humanos , Ratones , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/farmacología , Sistemas de Liberación de Medicamentos/métodos , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/administración & dosificación , Ratones Endogámicos BALB C , Ratones Desnudos , Masculino , Línea Celular Tumoral , Células HCT116 , Ensayos Antitumor por Modelo de Xenoinjerto/métodos , Biomarcadores de Tumor
8.
Forensic Toxicol ; 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38642241

RESUMEN

PURPOSE: A rapid and reliable method was developed and validated for the simultaneous analysis of 52 antibiotics (cephalosporins, penicillins, carbapenems, lincosamides, quinolones, nitroimidazoles, macrolides, sulfonamides, tetracyclines, glycopeptide) in urine and whole blood by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). METHOD: Analytes were extracted by dilution or protein precipitation and analyzed on an Agilent 1260 HPLC system coupled to an Agilent 6470 Triple Quadrupole Mass Spectrometer. RESULTS: The method attended method validation criteria. The limits of detection were equal or lower than 2.0 ng/mL, whereas the limits of quantification ranged from 0.1 to 10.0 ng/mL, from 0.1 to 5.0 ng/mL, in urine and whole blood, respectively. For all analytes, the bias and intra- and inter-day precision values were less than 14.7%. The ranges of recovery values of all antibiotics were 76.5-124.5% in whole blood and 76.3-121.8% in urine, values of the effects were lower than 25% in two matrices. No evidence of carryover was observed. The study of sample stability showed that almost all analytes were stable at 24 °C for 24 h, all analytes were stable at -20 °C for 14 days and at -80 °C for 30 days. Freeze-thaw cycles stability showed that antibiotics were stable except for imipenem. Autosampler stability study showed that all analytes were stable for 24 h, except for imipenem and amoxicillin. Applicability was proven by analyzing authentic whole blood (n = 86) and urine (n = 79) samples from patients under antibiotics treatment. Therefore, this method was applied to the analysis 3 forensic allergy cases, which were positive for at least one analyte. CONCLUSIONS: A simple, sensitive and high-throughput method for the simultaneous determination of different classes of antibiotics in urine and whole blood samples was developed and applied. This sensitive method was successfully applied to forensic cases.

9.
Adv Mater ; 36(18): e2312204, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38271730

RESUMEN

The electrochemical carbon dioxide (CO2) reduction reaction (CO2RR) involves a multistep proton-coupled electron transfer (PCET) process that generates a variety of intermediates, making it challenging to transform them into target products with high activity and selectivity. Here, a catalyst featuring a nanosheet-stacked sphere structure with numerous open and deep conical cavities (OD-CCs) is reported. Under the guidance of the finite-element method (FEM) simulations and theoretical analysis, it is shown that exerting control over the confinement space results in diffusion limitation of the carbon intermediates, thereby increasing local pressure and subsequently enhancing localized *CO coverage for dimerization. The nanocavities exhibit a structure-driven shift in selectivity of multicarbon (C2+) product from 41.8% to 81.7% during the CO2RR process.

10.
Phytochemistry ; 219: 113994, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38244959

RESUMEN

Five undescribed compounds, including two cholestane glycosides parispolyosides A and E, and three spirostanol glycosides parispolyosides B-D, were isolated from rhizome of Paris polyphylla var. chinensis (Franch.) Hara, together with twenty-one known steroidal saponins. Their chemical structures were elucidated on the basis of comprehensive analysis of 1D and 2D NMR, as well as HR-ESI-MS spectroscopic data. Two of these compounds demonstrated potent inhibitory effect on NO production stimulated by lipopolysaccharide in raw 264.7 cells with IC50 values of 61.35 µM and 37.23 µM. Four compounds exhibited moderate inhibitory activity against HepG2 cells with IC50 values ranging from 9.43 to 24.54 µM. Molecular docking analysis revealed that the potential mechanism of NO inhibition by the active compounds was associated with the interactions with iNOS protein.


Asunto(s)
Antineoplásicos , Liliaceae , Saponinas , Rizoma/química , Simulación del Acoplamiento Molecular , Saponinas/química , Liliaceae/química , Antiinflamatorios/farmacología
11.
Angew Chem Int Ed Engl ; 63(12): e202319913, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38284290

RESUMEN

Authentic surface structures under reaction conditions determine the activity and selectivity of electrocatalysts, therefore, the knowledge of the structure-activity relationship can facilitate the design of efficient catalyst structures for specific reactivity requirements. However, understanding the relationship between a more realistic active surface and its performance is challenging due to the complicated interface microenvironment in electrocatalysis. Herein, we proposed a standard research paradigm to effectively decipher the structure-activity relationship in electrocatalysis, which is exemplified in the CO2 electroreduction over SnO2 . The proposed practice has aided in discovering authentic/resting surface states (Sn layer) of SnO2 accountable for the electrochemical CO2 reduction reaction (CO2 RR) performance under electrocatalytic conditions, which then is corroborated in the subsequent CO2 RR experiments over SnO2 with different morphologies (nanorods, nanoparticles, and nanosheets) in combination with in situ characterizations. This proposed methodology is further extended to the SnO electrocatalysts, providing helpful insights into catalytic structures. It is believed that our proposed standard research paradigm is also applicable to other electrocatalytic systems, in the meantime, decreases the discrepancy between theory and experiments, and accelerates the design of catalyst structures that achieve sustainable performance for energy conversion.

12.
Forensic Sci Int ; 356: 111943, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38290418

RESUMEN

Anaphylaxis is a serious reaction of systemic hypersensitivity with that rapid onset and sudden death. Drug hypersensitivity, particularly induced by ß-lactams, is one of the most frequent causes of anaphylaxis in adults. But identification of anaphylactic shock, in forensic sciences recently, is difficult, because it mainly depends on nonspecific characteristic morphological changes, as well as exclusion and circumstantial evidence. Here, we detected DNA methylation signatures of ß-lactams-induced fatal anaphylactic shock with the Illumina Infinium Human Methylation EPIC BeadChip, to screen potential forensic biomarkers and reveal the molecular mechanisms of drug-induced anaphylaxis with fatal shock and sudden death. Our results indicated that DNA methylation was associated with ß-lactams-induced fatal anaphylactic shock, in which the hypomethylation played a vital role. We found that 1459 differentially methylated positions (DMPs) were mainly involved in ß-lactams-induced fatal anaphylactic shock by regulating MAPK and other signaling pathways. 18 DNA methylation signatures that could separate ß-lactams-induced anaphylactic shock from healthy individuals were identified. The altered methylation of DMPs can affect the transcription of corresponding genes and promote ß-lactams-induced fatal anaphylactic shock. The results suggest that DNA methylation can detect forensic identification markers of drug-induced anaphylaxis with fatal shock and sudden death, and it is an effective method for the forensic diagnosis.


Asunto(s)
Anafilaxia , Hipersensibilidad a las Drogas , Adulto , Humanos , Anafilaxia/inducido químicamente , Anafilaxia/genética , Anafilaxia/diagnóstico , beta-Lactamas/efectos adversos , Metilación de ADN , Biomarcadores/metabolismo , Muerte Súbita , Hipersensibilidad a las Drogas/complicaciones , Hipersensibilidad a las Drogas/diagnóstico
13.
Proc Natl Acad Sci U S A ; 121(4): e2309102121, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38232287

RESUMEN

Nonradicals are effective in selectively degrading electron-rich organic contaminants, which unfortunately suffer from unsatisfactory yield and uncontrollable composition due to the competitive generation of radicals. Herein, we precisely construct a local microenvironment of the carbon nitride-supported high-loading (~9 wt.%) Fe single-atom catalyst (Fe SAC) with sulfur via a facile supermolecular self-assembly strategy. Short-distance S coordination boosts the peroxymonosulfate (PMS) activation and selectively generates high-valent iron-oxo species (FeIV=O) along with singlet oxygen (1O2), significantly increasing the 1O2 yield, PMS utilization, and p-chlorophenol reactivity by 6.0, 3.0, and 8.4 times, respectively. The composition of nonradicals is controllable by simply changing the S content. In contrast, long-distance S coordination generates both radicals and nonradicals, and could not promote reactivity. Experimental and theoretical analyses suggest that the short-distance S upshifts the d-band center of the Fe atom, i.e., being close to the Fermi level, which changes the binding mode between the Fe atom and O site of PMS to selectively generate 1O2 and FeIV=O with a high yield. The short-distance S-coordinated Fe SAC exhibits excellent application potential in various water matrices. These findings can guide the rational design of robust SACs toward a selective and controllable generation of nonradicals with high yield and PMS utilization.

14.
Res Sq ; 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38260621

RESUMEN

C-H bond activation enables the facile synthesis of new chemicals. While C-H activation in short-chain alkanes has been widely investigated, it remains largely unexplored for long-chain organic molecules. Here, we report light-driven C-H activation in complex organic materials mediated by 2D transition metal dichalcogenides (TMDCs) and the resultant solid-state synthesis of luminescent carbon dots in a spatially-resolved fashion. We unravel the efficient H adsorption and a lowered energy barrier of C-C coupling mediated by 2D TMDCs to promote C-H activation. Our results shed light on 2D materials for C-H activation in organic compounds for applications in organic chemistry, environmental remediation, and photonic materials.

15.
Nat Nanotechnol ; 19(3): 345-353, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37903891

RESUMEN

Since their initial development, cell membrane-coated nanoparticles (CNPs) have become increasingly popular in the biomedical field. Despite their inherent versatility and ability to enable complex biological applications, there is considerable interest in augmenting the performance of CNPs through the introduction of additional functionalities. Here we demonstrate a genetic-engineering-based modular approach to CNP functionalization that can encompass a wide range of ligands onto the nanoparticle surface. The cell membrane coating is engineered to express a SpyCatcher membrane anchor that can readily form a covalent bond with any moiety modified with SpyTag. To demonstrate the broad utility of this technique, three unique targeted CNP formulations are generated using different classes of targeting ligands, including a designed ankyrin repeat protein, an affibody and a single-chain variable fragment. In vitro, the modified nanoparticles exhibit enhanced affinity towards cell lines overexpressing the cognate receptors for each ligand. When formulated with a chemotherapeutic payload, the modularly functionalized nanoparticles display strong targeting ability and growth suppression in a murine tumour xenograft model of ovarian cancer. Our data suggest genetic engineering offers a feasible approach for accelerating the development of multifunctional CNPs for a broad range of biomedical applications.


Asunto(s)
Ingeniería Genética , Nanopartículas , Humanos , Animales , Ratones , Línea Celular , Membrana Celular , Nanopartículas/química
16.
ACS Nano ; 17(22): 22859-22871, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-37930274

RESUMEN

Single-atom catalysts (SACs) offer immense potential in heterogeneous catalysis due to their maximized atomic utilization and high selectivity but suffer the problem of low reactivity in catalytic reductive reactions due to their high-valent state. Here, we demonstrate that supported palladium (Pd) ensembles consisting of a few zero-valent Pd atoms (Pd1+c-red/CN) exhibit exceptional reactivity in formic acid (FA) dehydrogenation and 4-chlorophenol (4-CP) dechlorination. The initial FA dehydrogenation and 4-CP dechlorination rates of Pd1+c-red/CN are 42-104 and 16-210 times higher than that of supported Pd SACs (Pd1-ox/CN), respectively. Experimental results and density functional theory (DFT) calculations reveal that optimal adsorption sites of Pd1+c-red/CN stimulate the formation of H*, which is indispensable for 4-CP dechlorination. Moreover, direct electron transfer from Pd atoms to FA with a high electron density on Pd1+c-red/CN also contributes to the rapid 4-CP dechlorination. The superior dehalogenation capability of Pd1+c-red/CN for organohalides of great environmental and health concerns suggested its immense application potential in environmental remediation. This work highlights the pivotal roles of the structure and valence state of Pd ensembles in catalytic reductive reactions and provides a strategy to broaden the application of Pd-based catalysts for dehydrogenation and dehalogenation.

17.
Nano Lett ; 23(17): 7941-7949, 2023 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-37602707

RESUMEN

Cell membrane-based nanovaccines have demonstrated attractive features due to their inherently multiantigenic nature and ability to be formulated with adjuvants. Here, we report on cellular nanodiscs fabricated from cancer cell membranes and incorporated with a lipid-based adjuvant for antitumor vaccination. The cellular nanodiscs, with their small size and discoidal shape, are readily taken up by antigen-presenting cells and drain efficiently to the lymph nodes. Due to its highly immunostimulatory properties, the nanodisc vaccine effectively stimulates the immune system and promotes tumor-specific immunity. Using a murine colorectal cancer model, strong control of tumor growth is achieved in both prophylactic and therapeutic settings, particularly in combination with checkpoint blockades. Considerable therapeutic efficacy is also observed in treating a weakly immunogenic metastatic melanoma model. This work presents a new paradigm for the design of multiantigenic nanovaccines that can effectively activate antitumor immune responses and may be applicable to a wide range of cancers.


Asunto(s)
Melanoma , Vacunación , Animales , Ratones , Membrana Celular , Membranas , Células Presentadoras de Antígenos , Adyuvantes Inmunológicos/uso terapéutico
18.
Sci Rep ; 13(1): 11190, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37433899

RESUMEN

A gas chromatography-mass spectrometry (GC-MS) method for the determination of difenidol hydrochloride in biological specimens has been developed. The method exhibited excellent recovery (> 90%) and precision (RSD < 10%), and the LOD was 0.05 µg/mL or µg/g, which met the requirements of bioanalytical method. Through the animal model of the forensic toxicokinetics, the dynamic distribution, postmortem redistribution (PMR) and stability in specimen preservation process of difenidol in animals were studied. The experimental results showed that after intragastric administration, the difenidol's concentrations in the heart-blood and various organs increased over time except stomach, and then decreased gradually after reaching the peaks of concentration. The toxicological kinetics equation and toxicokinetic parameters were established by processing the data of the mean drug concentration of difenidol changing with time. In PMR experiment, the concentrations of difenidol in some organs closer to the gastrointestinal tract (heart-blood, heart, liver, lung, kidney, and spleen) changed significantly at different time points. But the concentration of difenidol in brain tissues which were far away from the gastrointestinal tract and muscles with larger overall mass was relatively stable. PMR of difenidol was therefore confirmed. Thus, the effect of PMR on the concentration of difenidol in the specimens should be considered in cases involving difenidol poisoning or death. Furthermore, the stability of difenidol in heart-blood samples from poisoned rats was investigated at various time points and under different preservation conditions (20 °C, 4 °C, - 20 °C and 20 °C (1% NaF)) for a period of two months. Difenidol was stable and did not decompose in the preserved blood. Therefore, this study provided the experimental basis for the forensic identification of the cases of difenidol hydrochloride poisoning (death). PMR has been verified by practical lethal cases.


Asunto(s)
Medicina Legal , Piperidinas , Animales , Ratas , Toxicocinética , Piperidinas/toxicidad , Autopsia
19.
Molecules ; 28(13)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37446949

RESUMEN

Pollen, as an important component of Eucommia ulmoides (EUP), is rich in nutrients and is receiving increasing attention. At present, there are no reports on research related to the chemical composition and quality standards of EUP, and there are significant quality differences and counterfeit phenomena in the market. This study used a UPLC-QTOF-MS system to identify 49 chemical components in EUP for the first time. In the second step, 2,2-diphenyl-1-picrylhydrazyl (DPPH)-HPLC antioxidant activity screening technology was used to identify the main active components of EUP, quercetin-3-O-sophoroside (QSH), quercetin-3-O-sambubioside (QSB), and quercetin 3-O-neohesperidoside (QNH), and their purification, preparation, and structure identification were carried out. Third, molecular docking was used to predict the activity of these components. Fourth, the intracellular ROS generation model of RAW264.7 induced by H2O2 was used to verify and evaluate the activity of candidate active ingredients to determine their feasibility as Q-markers. Finally, a quality control method for EUP was constructed using the three selected components as Q-markers. The identification of chemical components and the discovery, prediction, and confirmation of characteristic Q-markers in EUP provide important references for better research on EUP and the effective evaluation and control of its quality. This approach provides a new model for the quality control of novel foods or dietary supplements.


Asunto(s)
Antioxidantes , Eucommiaceae , Antioxidantes/química , Quercetina , Cromatografía Líquida de Alta Presión/métodos , Eucommiaceae/química , Peróxido de Hidrógeno , Simulación del Acoplamiento Molecular , Polen
20.
J Colloid Interface Sci ; 650(Pt B): 1949-1957, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37517194

RESUMEN

The oxygen evolution reaction (OER) is a key process in various energy storage/generation technologies. Tuning the electronic structures of catalysts is an effective approach to improve the catalyst's activity. In this work, we synthesized Ce-doped cobalt-organic frameworks with benzene-1, 4-dicarboxylic acid (BDC) as the ligand as efficient OER electrocatalysts (denoted as Co3Ce1 BDC) with excellent stability and improved catalytic performance. The introduced Ce in Co3Ce1 BDC changes the surface configuration and tunes electronic structures of the active Co site, leading to enhanced interaction between intermediates and catalysts. Besides, the specific surface area, reaction kinetics, charge transfer efficiency, and turnover frequency are also improved in the presence of Ce. As a result, the Co3Ce1 BDC demonstrated excellent performance with a low overpotential of 285 mV at a current of 10 mA·cm-2, a preferable Tafel slope of 56.1 mV·dec-1, and an excellent durability in 1 M KOH, indicating the potential for practical applications in water splitting and other energy storage technologies wherein the OER plays a critical role. Comprehensive theoretical calculations and modeling further identified the key role of Ce in modulating the electronic structure and OER activity of cobalt-organic frameworks. Most importantly, this work provides a new strategy to the development of efficient cobalt-organic framework catalysts in OER-related applications.

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