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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124970, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39153349

RESUMEN

Due to their exceptional optical properties and adjustable functional characteristics, hydrogen-bonded organic frameworks (HOFs) demonstrate significant potential in applications such as sensing, information encryption. However, studies on the synthesis of HOFs designed to construct multifunctional platforms are scant. In this work, we report the synthesis of a new fluorescent HOF by assembling melem and isophthalic acid (IPA), designated as HOF-IPA. HOF-IPA exhibited good selectivity and sensitivity towards Fe3+, making it suitable as a fluorescent sensor for Fe3+ detection. The sensor achieved satisfactory recoveries ranging from 97.79 % to106.42 % for Fe3+ sensing, with a low relative standard deviation (RSD) of less than 3.33 %, indicating significant application potential for HOF-IPA. Due to the ability of F- to mask the electrostatic action on the surface of Fe3+ and inhibit the photoelectron transfer (PET) of HOF-IPA, the HOF-IPA - Fe3+ system can be utilized as a fluorescent "off-on" sensor for F- detection. Additionally, owing to the colorless, transparent property of HOF-IPA in aqueous solution under sunlight and its blue fluorescence property under UV light (color) or microplate reader (fluorescence intensity), HOF-IPA based ink can be used for various types of information encryption, and all yielding favorable outcomes.

2.
Int J Cancer ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949756

RESUMEN

Gliomas are primary brain tumors and are among the most malignant types. Adult-type diffuse gliomas can be classified based on their histological and molecular signatures as IDH-wildtype glioblastoma, IDH-mutant astrocytoma, and IDH-mutant and 1p/19q-codeleted oligodendroglioma. Recent studies have shown that each subtype of glioma has its own specific distribution pattern. However, the mechanisms underlying the specific distributions of glioma subtypes are not entirely clear despite partial explanations such as cell origin. To investigate the impact of multi-scale brain attributes on glioma distribution, we constructed cumulative frequency maps for diffuse glioma subtypes based on T1w structural images and evaluated the spatial correlation between tumor frequency and diverse brain attributes, including postmortem gene expression, functional connectivity metrics, cerebral perfusion, glucose metabolism, and neurotransmitter signaling. Regression models were constructed to evaluate the contribution of these factors to the anatomic distribution of different glioma subtypes. Our findings revealed that the three different subtypes of gliomas had distinct distribution patterns, showing spatial preferences toward different brain environmental attributes. Glioblastomas were especially likely to occur in regions enriched with synapse-related pathways and diverse neurotransmitter receptors. Astrocytomas and oligodendrogliomas preferentially occurred in areas enriched with genes associated with neutrophil-mediated immune responses. The functional network characteristics and neurotransmitter distribution also contributed to oligodendroglioma distribution. Our results suggest that different brain transcriptomic, neurotransmitter, and connectomic attributes are the factors that determine the specific distributions of glioma subtypes. These findings highlight the importance of bridging diverse scales of biological organization when studying neurological dysfunction.

3.
J Chromatogr A ; 1717: 464693, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38295742

RESUMEN

A magnetic molecular imprinted covalent organic framework composite (MCOF-MIP) that possessed the 'dual-selectivity' of a covalent organic framework and molecular imprinted polymer (MIP) with rapid response performance was successfully prepared for the removal of bisphenol AF (BPAF) from real water and blood samples. First, the MCOF was separately synthesized using magnetic Fe3O4 as the magnetic core, 1,3,5-triaminobenzene and 2,5-dibromobenzene-1,4-diformaldehyde as precursors and a deep eutectic solvent (DES) as the solvent using a solvothermal synthesis method. The MCOF showed high crystallinity and good adsorption capacities for BPAF (107.4 mg g-1), bisphenol A (113.6 mg g-1), bisphenol S (120.0 mg g-1) and bisphenol F (82.1 mg g-1). To further improve the selectivity for BPAF, an MIP, which uses BPAF as a template, was introduced to form the MCOF-MIP. Due to the dual selectivity of MCOF and MIP, the MCOF-MIP exhibited relatively high selective adsorption capacity to BPAF (243.1 mg g-1) compared to that for the MCOF (107.4 mg g-1), while the adsorption capacities (149.7-109.4 mg g-1) for the other three compounds were not significantly improved. Furthermore, a magnetic solid-phase extraction (MSPE) method was established, and MSPE parameters such as adsorbent dosage, adsorption time, desorption solvent and desorption time were optimized. Combined with high-performance liquid chromatography with diode-array detection (HPLC-DAD) analysis, a rapid and sensitive method was developed to detect BPAF, which showed good linearity (r > 0.9969) ranging from 0.1 to 400 µg mL-1. Low limits of detection (0.04 µg mL-1, S/N = 3) and quantitation (0.1 µg mL-1, S/N = 10) and good precision with low relative SDs (<1.2 % for intra-day and <1.1 % for inter-day) were also obtained. Finally, MSPE coupled with HPLC-DAD was employed for the analysis of BPAF in water and blood samples, and the recoveries of BPAF were satisfactory (91.1-112.6 %).


Asunto(s)
Compuestos de Bencidrilo , Fluorocarburos , Estructuras Metalorgánicas , Impresión Molecular , Estructuras Metalorgánicas/química , Impresión Molecular/métodos , Agua/química , Solventes/química , Adsorción , Extracción en Fase Sólida/métodos , Fenómenos Magnéticos , Cromatografía Líquida de Alta Presión , Límite de Detección
4.
Prog Neurobiol ; 233: 102570, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38232783

RESUMEN

Just as navigating a physical environment, navigating through the landscapes of spontaneous brain states may also require an internal cognitive map. Contemporary computation theories propose modeling a cognitive map from a reinforcement learning perspective and argue that the map would be predictive in nature, representing each state as its upcoming states. Here, we used resting-state fMRI to test the hypothesis that the spaces of spontaneously reoccurring brain states are cognitive map-like, and may exhibit future-oriented predictivity. We identified two discrete brain states of the navigation-related brain networks during rest. By combining pattern similarity and dimensional reduction analysis, we embedded the occurrences of each brain state in a two-dimensional space. Successor representation modeling analysis recognized that these brain state occurrences exhibit place cell-like representations, akin to those observed in a physical space. Moreover, we observed predictive transitions of reoccurring brain states, which strongly covaried with individual cognitive and emotional assessments. Our findings offer a novel perspective on the cognitive significance of spontaneous brain activity and support the theory of cognitive map as a unifying framework for mental navigation.


Asunto(s)
Encéfalo , Emociones , Humanos , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Cognición
5.
Int J Biol Macromol ; 254(Pt 3): 128052, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37967602

RESUMEN

Typically, the tailorable versatility of biomass aerogels is attributed to the tunable internal molecular structure, providing broad application prospects. Herein, a simple and novel preparation strategy for developing multifunctional dual-network chitosan/itaconic acid (CSI) aerogel with tunability by using freeze-drying and vacuum heat treatment techniques. By regulating the temperature and duration of amidation reaction, electrostatic interactions between chitosan (CS) and itaconic acid (IA) was abstemiously converted into amide bond in frozen aerogel, with IA acting as an efficient in-situ cross-linking agent, which yielded CSI aerogels with different electrostatic/covalent cross-linking ratios. Heat treatment and tuning of the covalent cross-linking degree of CSI aerogel changed their microstructure and density, which led to enhanced performance. For example, the specific modulus of CSI1.5-160 °C-5 h (71.69 ± 2.55 MPa·cm3·g-1) increased by 119 % compared to that of CSI1.5 (32.73 ± 0.718 MPa·cm3·g-1), converting the material from superhydrophilic to hydrophobic (124° ± 3.6°), exhibiting favorable stability and heat transfer performance. In addition, part of -NH3+ of CS was retained in the electrostatic cross-linked network, endowing the aerogel with antibacterial properties. The findings of this study provide insights and a reliable strategy for fabricating biomass aerogel with good comprehensive performance via ingenious structural design and simple regulation methods.


Asunto(s)
Quitosano , Amidas , Antibacterianos , Biomasa
6.
Anal Methods ; 15(44): 5919-5946, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37916394

RESUMEN

Covalent organic frameworks (COFs) are a class of porous crystalline materials based on organic building blocks containing light elements, such as C, H, O, N, and B, interconnected by covalent bonds. Because of their regular crystal structure, high porosity, stable mechanical structure, satisfactory specific surface area, easy functionalization, and high tunability, they have important applications in several fields. Currently, most of the established methods based on COFs can only be used for individual detection or adsorption of the target. Impressively, fluorescent COFs as a special member of the COF family are able to achieve highly selective and sensitive detection of target pollutants by fluorescence enhancement or quenching. The construction of a dual-functional platform for detection and adsorption based on fluorescent COFs can enable the simultaneous realization of visual monitoring and adsorption of target pollutants. Therefore, this paper reviews the research progress of fluorescent COFs as fluorescence sensors and adsorbents. First, the fluorescent COFs were classified according to the different bonding modes between the building blocks, and then the applications of fluorescent COF-based detection and adsorption bifunctional materials for various environmental contaminants were highlighted. Finally, the challenges and future application prospects of fluorescent COFs are discussed.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 298: 122803, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37148662

RESUMEN

Clozapine (CLZ) is known as the most effective antipsychotic medication for schizophrenia. However, low dosage or over dosage of CLZ is adverse to the treatment of Schizophrenia. Thus, it is necessary to develop effective detection method for CLZ. Recently, due to the advantages such as excellent optical properties, good photobleachability and sensitivity, carbon dots (CDs)-based fluorescent sensors for the detection of target analytes have drawn a great deal of attention. In this work, blue fluorescent CDs (Named as B-CDs) with quantum yield (QY) as high as 38% were obtained by using carbonized human hair as source material through one-step dialysis method for the first time. B-CDs showed obvious graphite-like structure with an average of 1.76 nm, containing abundant functional groups such as -C=O, amino N and C-N on the surface of carbon cores. Optical analysis showed that the B-CDs exhibited excitation-dependent emission property with maximum emission wavelength of 450 nm. Moreover, B-CDs were further applied as a fluorescence sensor to the detection of CLZ. The B-CDs based sensor exhibited a good quenching response by CLZ through the inner filter effect and static quenching mechanism with a limit of detection of 67 ng/mL, which was much lower than the minimal effective concentration in blood (0.35 µg/mL). Finally, to test the practical application value of the developed fluorescence method, the determination of the content of CLZ in tablets and the concentration in blood was carried out. Compared with the results of high-performance liquid chromatography (HPLC) method, it can be found that the constructed fluorescence detection method showed high accuracy and had great application potential in the detection of CLZ. Additionally, the results of cytotoxicity experiment showed that B-CDs had low cytotoxicity, which laid the foundation for the subsequent application of B-CDs in biological systems.


Asunto(s)
Clozapina , Puntos Cuánticos , Humanos , Puntos Cuánticos/química , Carbono/química , Espectrometría de Fluorescencia/métodos , Colorantes Fluorescentes/química , Cabello
8.
J Sep Sci ; 46(6): e2200996, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36651533

RESUMEN

Herein, a covalent organic framework, which was fabricated at room temperature by using 1,3,5-tris(p-formylphenyl) benzene and 1,3,5-tris(4-aminophenyl)benzene as building blocks, was employed as an adsorbent for solid-phase extraction of dyes including congo red, methyl blue and direct red 80 for the first time. The prepared covalent organic framework was properly characterized by different techniques and the results revealed that it had a uniform spherical structure, high crystallinity, satisfactory surface area, and good thermal stability. Moreover, the adsorption performance of the material was explored by using static and dynamic adsorption experiments and the results indicated that the material showed good adsorption capacities for three dyes with adsorption capacities in the range of 55.25-284.10 mg/g and the adsorption equilibrium can be achieved in 15 min. Further, to achieve the best adsorption effects of the material, the influence parameters such as pH, ionic strength, type of desorption solvent, and the material dosage in the solid-phase extraction column, were optimized in turn. Finally, under optimal conditions, the solid-phase extraction coupled with HPLC was applied to the analysis of dyes in food and water samples. The recoveries of dyes in actual samples were satisfactory, revealing the unique applicability of the material in the sample pretreatment field.

9.
J Chromatogr A ; 1681: 463478, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36099693

RESUMEN

Herein, a hydroxyl­riched covalent organic framework (named COF-DES-1) was synthesized using 1,3,5-tris(4-aminophenyl)benzene and 2,5-dihydroxyterephthalaldehyde as building blocks and employed as a coating of solid-phase microextraction (SPME) fiber. Ascribed to the advantages (e.g. suitable pore size and rich functional group characteristics) of coating, the SPME fiber showed good adsorption capacities to flavonoids aglycones including luteolin and quercetagetin, and the maximum adsorption capacities for them were 145.31 µg and 84.75 µg, respectively. Due to the size exclusion property of COF-DES-1, SPME fiber showed good protein exclusion effects on seven selected proteins with high exclusion efficiencies (>93%). Accordingly, an attractive strategy of the combination of COF-DES-1 based SPME fiber and HPLC-MS/MS was proposed for the extraction and determination of luteolin, quercetagetin or their metabolites. The results revealed that the fiber can be effectively applied to extract luteolin and its metabolites, and quercetagetin from mice's palsma. Compared with the traditional protein precipitation methods, the extraction effects of SPME fiber based extraction method were much better, indicating the promising applicability of the fiber for the enrichment of flavonoids aglycones or their metabolites in biological samples.


Asunto(s)
Estructuras Metalorgánicas , Microextracción en Fase Sólida , Animales , Benceno , Flavonas , Flavonoides , Luteolina , Ratones , Microextracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem
10.
Molecules ; 27(15)2022 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-35956952

RESUMEN

The mechanism of ginsenoside Rh3 activity against cancer remains unclear. This study aimed to investigate the underlying mechanism. The effects of Rh3 on the cell proliferation, migration and invasion, and cycle and apoptosis were analyzed using CCK-8 assay, transwell migration assay and flow cytometry, respectively. The RNA transcriptome was sequenced and data were analyzed by R software. Protein expression and protein-protein interactions were determined by Western blotting and co-immunoprecipitation, respectively. The results showed Rh3 inhibited HCT116 cell proliferation, invasion, and migration, arrested cells at G1 phase; and increased apoptosis. Rh3 downregulated 314 genes and upregulated 371 genes. Gene Set Enrichment Analysis (GSEA) using The Kyoto Encyclopedia of Genes Genomics ranked DNA replication first, while GSEA using Gene Ontology ranked the initiation of DNA replication first. Compared with tumor data from The Cancer Genome Atlas (TCGA), most of genes related to DNA replication were oppositely regulated by Rh3. Furthermore, Rh3 down-regulated key protein expression related to DNA replication (Orc6, Cdt1, and Mcm2), but did not affect the loading of Mcm complexes onto ORC complexes nor the phosphorylation at ser139 of Mcm2. Therefore, Rh3 may inhibit colorectal cancer HCT116 cells by downregulation of genes related to DNA replication.


Asunto(s)
Neoplasias Colorrectales , Ginsenósidos , Proliferación Celular , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Perfilación de la Expresión Génica , Ginsenósidos/farmacología , Células HCT116 , Humanos
11.
J Pharm Biomed Anal ; 208: 114403, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-34798392

RESUMEN

Morinda officinalis How (MO) possesses prominent tonifying kidney yang and strengthening bone and muscle effects in traditional Chinese medicine (TCM). Due to the complexity of MO components, the chemical mechanism leading to efficacy changes of MO caused by processing remain unclear. This study aimed to investigate and discover quality markers (Q-markers) related to the clinical efficacy of processed MO. The different processed products of MO have different clinical applications, although they originate from the same medicinal herb. The active chemical components from raw and processed MO that protect against reproductive oxidative stress damage were evaluated. The processed products of MO were prepared by different processing methods. The changes in oligosaccharides during processing were characterized by high-performance liquid chromatography with an evaporative light scattering detector (HPLC-ELSD), and the differential components in raw and processed MO were analyzed using SA, HCA, PCA, and OPLS-DA methods. The protective effects of raw and processed MO oligosaccharides (MOOs) against reproductive oxidative stress damage were evaluated based on the spermatic number, spermatic survival rate, abnormal sperm ratio and serum biochemical indicators in cyclophosphamide-induced (CTX-induced) male mice. The results revealed that processed MOOs had better pharmacological effects than raw MOOs. Therefore, gray correlation analysis (GRA) and the technique for order preference by similarity to ideal solution (TOPSIS) methods were used to investigate the spectrum-effect relationships of MOOs. Spectrum-effect relationship analysis revealed that all of the characteristic peaks contributed to the treatment of reproductive oxidative stress damage, and the relative correlation degrees were greater than 0.6. Among them, the peaks 1 F-fructofuranosylnystose, nystose, and 1-kestose and the peaks X2-X5, which were most closely correlated to the treatment of reproductive oxidative stress damage, were identified as inulin-oligosaccharides and inulo-oligosaccharides, respectively. It was proposed that these constituents could be considered Q-markers for processed products of MO. Thus, this study aimed to explore chemical markers that correlate with the clinical efficacy of processed MO.


Asunto(s)
Medicamentos Herbarios Chinos , Morinda , Animales , Cromatografía Líquida de Alta Presión , Masculino , Medicina Tradicional China , Ratones , Oligosacáridos
12.
Int J Biol Macromol ; 193(Pt B): 1043-1049, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34800517

RESUMEN

Microgel affords a porous and swollen microstructure for the establishment of pulmonary delivery system with sustained released properties. Here, we report a microgel (with the diameter around 4 µm) prepared with a precipitation method, synthesized by coordinating Zn2+ to the Schiff base cross-linked carboxymethyl chitosan and glycol split hyaluronate. The microgel has shown well swollen and pH sensitive behaviors, high safety and biocompatibility in vitro. Besides, the biomaterial could escape from macrophage phagocytosis, a key factor contribute to quick drug clearance in the lung after co-incubated with RAW 264.7 cells. In consist with this, the bovine serum albumin loaded in the microgel showed sustained release behavior in 24 h in vitro; meanwhile, the drug had a retention time up to 36 h in the lung and followed by clearance in ICR mice through pulmonary administration. Thus, our microgel platform provides a promising candidate for pulmonary drug delivery systems with controlled release rate.


Asunto(s)
Quitosano/análogos & derivados , Portadores de Fármacos , Ácido Hialurónico , Pulmón/metabolismo , Microgeles/química , Zinc , Animales , Quitosano/química , Quitosano/farmacocinética , Quitosano/farmacología , Portadores de Fármacos/síntesis química , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacología , Ácido Hialurónico/química , Ácido Hialurónico/farmacocinética , Ácido Hialurónico/farmacología , Ratones , Ratones Endogámicos ICR , Células 3T3 NIH , Células RAW 264.7 , Zinc/química , Zinc/farmacocinética , Zinc/farmacología
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