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1.
Molecules ; 29(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38542926

RESUMO

Molecular imprinting technology is widely used for the specific identification of compounds, but the selective recognition mechanisms of the same compounds still need to be further studied. Based on differences in hydrogen bond size and orientation, molecularly imprinted polymers (MIPs) were designed to adsorb flavonols with the same parent core and different hydroxyl groups. A surface-imprinted material was designed with silicon dioxide as the carrier, myricetin as the template molecule, and methacrylic acid (MAA) as the functional monomer. Scanning electron microscopy (SEM), Brunauer-Emmett-Teller surface area (BET) analyses, Fourier-transform infrared spectroscopy (FT-IR), and other characterization experiments were carried out. The intrinsic mechanism of the MIPs was also explored. The MIPs showed good adsorption of myricetin and other flavonoids through hydrogen bonding and steric hindrance. The adsorption capacity was 3.12-9.04 mg/g, and the imprinting factor was 1.78-3.37. Flavonoids with different hydroxyl groups in different numbers and directions had different hydrogen bond strengths with functional monomers. R2, R4, and R1 on 2-phenylchromogenone had stronger electronegativity, and the hydroxyl group was also more likely to form and have stronger hydrogen bonds. The hydroxyl negativity and the degree of steric hindrance of flavonoids played a major role in the recognition of molecularly imprinted materials. This study is of great significance for the synthesis of and selection of templates for analogous molecular imprinting materials.

2.
Sleep Med ; 117: 79-86, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38518586

RESUMO

BACKGROUND: While negative life events (NLEs) have been linked to an increased risk of sleep disturbance among adolescents, the mechanisms of this impact still lack further examination. The current study aimed to explore whether intolerance of uncertainty (IU), a dispositional transdiagnostic vulnerability factor for psychopathology, could act as a mediator and/or moderator in the link from NLEs to sleep disturbance. METHODS: A longitudinal nested subsample of 54,240 Chinese adolescents (aged 9-19) were surveyed at baseline (Timepoint 1) and six months later (Timepoint 2). They completed questionnaires to assess their IU, NLEs, sleep disturbance and sociodemographic characteristics. Mediation and moderation analyses were conducted to test our hypotheses. RESULTS: Upon adjusting for covariates, IU was found to mediate the relationship between NLEs and residual changes in sleep disturbance over a six-month period, with the mediation effect accounting for 31.8%. Additionally, the moderating role of IU in this relationship was also identified, suggesting that a high level of IU exacerbated the effect of NLEs on sleep disturbance. CONCLUSIONS: In conclusion, our findings shed light on the dual roles of IU in the link from NLEs to sleep disturbance, holding significant practical implications for preventing and intervening in sleep disturbance among adolescents. To mitigate the risk of sleep disturbance among adolescents experiencing NLEs, timely assessments of IU and tailored interventions to enhance uncertainty tolerance are necessary.


Assuntos
Personalidade , Humanos , Adolescente , Incerteza , Inquéritos e Questionários , Fatores de Risco
3.
Front Med (Lausanne) ; 11: 1328750, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38348339

RESUMO

Introduction: While new targeted therapies have advanced psoriasis treatment, real-world data on comparative effectiveness is lacking. This study analyzed treatment regimens and response in an observational cohort, examining potential disparities between clinical trials and routine practice. Methods: Data from the Psoriasis Standardized Diagnosis and Treatment Center registry were analyzed. Patients with ≥1 follow-up were included. Treatment response was assessed using PASI 50/90 criteria. Factors associated with response were analyzed. Results: 407 patients were included (46 first-time diagnosed, 361 previously diagnosed). A higher proportion of first-time diagnosed patients achieved treatment response than previously diagnosed (76.1% vs. 62.6%). Multivariable analysis identified factors associated with reduced response in previously treated patients. Conclusion: This real-world study found lower treatment response rates compared to clinical trials, especially in previously treated patients. Disparities highlight remaining unmet needs for psoriasis management. Combination and rotational strategies may improve outcomes in patients unresponsive to available therapies. Ongoing research on novel targets and pathways is warranted to address treatment gaps.

4.
J Cell Mol Med ; 28(1): e18043, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37985432

RESUMO

This research aimed to find important genes and pathways related to cellular senescence (CS) in diabetic foot ulcers (DFU) and to estimate the possible pathways through which CS affects diabetic foot healing. The GSE80178 dataset was acquired from the Gene Expression Omnibus (GEO) database, containing six DFU and three diabetic foot skin (DFS) samples. The limma package was used to identify differentially expressed genes (DEGs). At the same time, DEGs associated with CS (CS-DEGs) were found using the CellAge database. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted on the CS-DEGs. A protein-protein interaction (PPI) network was built using the String database, and the cytoHubba plug-in within Cytoscape helped identify hub genes. Lastly, the miRNA-TF-mRNA regulatory network for these hub genes was established. In total, 66 CS-DEGs were obtained. These genes mainly focus on CS, Kaposi sarcoma-associated herpesvirus infection and Toll-like receptor signalling pathway. Eight hub genes were identified to regulate cell senescence in DFU, including TP53, SRC, SIRT1, CCND1, EZH2, CXCL8, AR and CDK4. According to miRNA-TF-mRNA regulatory network, hsa-mir-132-3p/SIRT1/EZH2 axis is involved in senescence cell accumulation in DFU.


Assuntos
Diabetes Mellitus , Pé Diabético , MicroRNAs , Humanos , Sirtuína 1/genética , Redes Reguladoras de Genes , MicroRNAs/genética , Perfilação da Expressão Gênica , RNA Mensageiro/genética , Biologia Computacional
5.
J Virol ; 97(12): e0123223, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38051045

RESUMO

IMPORTANCE: Over the past decade, increasing evidence has shown that circular RNAs (circRNAs) play important regulatory roles in viral infection and host antiviral responses. However, reports on the role of circRNAs in Zika virus (ZIKV) infection are limited. In this study, we identified 45 differentially expressed circRNAs in ZIKV-infected A549 cells by RNA sequencing. We clarified that a downregulated circRNA, hsa_circ_0007321, regulates ZIKV replication through targeting of miR-492 and the downstream gene NFKBID. NFKBID is a negative regulator of nuclear factor-κB (NF-κB), and we found that inhibition of the NF-κB pathway promotes ZIKV replication. Therefore, this finding that hsa_circ_0007321 exerts its regulatory role on ZIKV replication through the miR-492/NFKBID/NF-κB signaling pathway has implications for the development of strategies to suppress ZIKV and possibly other viral infections.


Assuntos
RNA Circular , Infecção por Zika virus , Zika virus , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , RNA Circular/genética , Transdução de Sinais , Zika virus/genética , Zika virus/metabolismo , Infecção por Zika virus/genética
6.
ACS Nano ; 17(18): 18253-18265, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37669410

RESUMO

Defects are generally considered to be effective and flexible in the catalytic reactions of lithium-sulfur batteries. However, the influence of the defect concentration on catalysis remains ambiguous. In this work, molybdenum sulfide with different sulfur vacancy concentrations is comprehensively modulated, showing that the defect level and the adsorption-catalytic performance result in a volcano relationship. Moreover, density functional theory and in situ experiments reveal that the optimal level of sulfur defects can effectively increase the binding energy between molybdenum sulfide and lithium polysulfides (LiPSs), lower the energy barrier of the LiPS conversion reaction, and promote the kinetics of Li2S bidirectional catalytic reaction. The lower bidirectional catalytic performance incited by excessive or deficient sulfur defects is mainly due to the deformed geometrical structures and reduced adsorption of key LiPSs on the catalyst surface. This work underscores the imperative of controlling the defect content and provides a potential approach to the commercialization of lithium-sulfur batteries.

7.
Artigo em Inglês | MEDLINE | ID: mdl-37659028

RESUMO

Intolerance of uncertainty (IU) is widely considered a transdiagnostic risk and maintaining factor for psychiatric disorders. However, little is known about the overall nature and profile of IU among adolescents. This study aims to investigate the profiles of IU among Chinese adolescents and explore their associations with sociodemographic characteristics and mental health problems. A sample of 108,540 adolescents provided data on IU, sociodemographic characteristics, and mental health via an online platform. Latent profile analysis revealed three profiles: Low IU, Medium IU, and High IU. Girls, older adolescents, and those with specific sociodemographics were more likely to belong to the "High IU" profile. Furthermore, the "High IU" profile was associated with the highest risk of several mental health problems. These findings provided valuable information for early prevention and intervention strategies targeting IU and highlighted the importance of IU-based interventions for mental health among adolescents.

9.
Anal Chem ; 95(29): 11070-11077, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37428886

RESUMO

The class-selective molecular-imprinted polymers (MIPs) have shown the recognition ability to multiple targeted molecules through using one or multiple templates. However, choosing the right templates, the core problem, still lacks a systemic guide and decision-making. In this work, we propose a strategy of selecting templates through expanding the recognition width for the improvement of class-selectivity. First, three families of genotoxic impurity (GTI) were selected as model objects, and the spatial size and binding energy of each GTI-monomer complexes were obtained and compared by computational simulation. The two indexes of energy width (WE) and size width (WL) were introduced to compare the similarity and differences on the two recognition factors, binding strength and spatial size, among these GTIs in each family. Through shortening the width to increase similarity on binding energy and size, the dual templates in the aromatic amines (AI) family and sulfonic acid esters (SI) family were successfully selected. Correspondingly, the prepared dual-template MIPs in the two GTI families can simultaneously recognize all the GTIs comparing with that of single template MIP, respectively. Meanwhile, through comparing the adsorption capacity of the selected template and its analogues in one GTI family, the recognition efficiency of the dual-template MIPs was higher than that of the single-template MIP. This indicates that though using the selected right templates, the higher class-selectivity and the larger recognition width can be realized. Thus, this work can solve the problem of blind template selection, and provide the useful theoretical guidance for designing family-selective molecular imprinting.


Assuntos
Impressão Molecular , Adsorção , Polímeros/química , Aminas , Simulação por Computador
10.
ACS Infect Dis ; 9(7): 1424-1436, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37300493

RESUMO

Mitophagy is a selective degradation mechanism that maintains mitochondrial homeostasis by eliminating damaged mitochondria. Many viruses manipulate mitophagy to promote their infection, but its role in Zika virus (ZIKV) is unclear. In this study, we investigated the effect of mitophagy activation on ZIKV replication by the mitochondrial uncoupling agent niclosamide. Our results demonstrate that niclosamide-induced mitophagy inhibits ZIKV replication by eliminating fragmented mitochondria, both in vitro and in a mouse model of ZIKV-induced necrosis. Niclosamide induces autophosphorylation of PTEN-induced putative kinase 1 (PINK1), leading to the recruitment of PRKN/Parkin to the outer mitochondrial membrane and subsequent phosphorylation of ubiquitin. Knockdown of PINK1 promotes ZIKV infection and rescues the anti-ZIKV effect of mitophagy activation, confirming the role of ubiquitin-dependent mitophagy in limiting ZIKV replication. These findings demonstrate the role of mitophagy in the host response in limiting ZIKV replication and identify PINK1 as a potential therapeutic target in ZIKV infection.


Assuntos
Infecção por Zika virus , Zika virus , Camundongos , Animais , Mitofagia , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Infecção por Zika virus/tratamento farmacológico , Niclosamida/farmacologia , Ubiquitina/metabolismo
11.
Biomaterials ; 300: 122179, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37315386

RESUMO

Oxygenating biomaterials can alleviate anoxic stress, stimulate vascularization, and improve engraftment of cellularized implants. However, the effects of oxygen-generating materials on tissue formation have remained largely unknown. Here, we investigate the impact of calcium peroxide (CPO)-based oxygen-generating microparticles (OMPs) on the osteogenic fate of human mesenchymal stem cells (hMSCs) under a severely oxygen deficient microenvironment. To this end, CPO is microencapsulated in polycaprolactone to generate OMPs with prolonged oxygen release. Gelatin methacryloyl (GelMA) hydrogels containing osteogenesis-inducing silicate nanoparticles (SNP hydrogels), OMPs (OMP hydrogels), or both SNP and OMP (SNP/OMP hydrogels) are engineered to comparatively study their effect on the osteogenic fate of hMSCs. OMP hydrogels associate with improved osteogenic differentiation under both normoxic and anoxic conditions. Bulk mRNAseq analyses suggest that OMP hydrogels under anoxia regulate osteogenic differentiation pathways more strongly than SNP/OMP or SNP hydrogels under either anoxia or normoxia. Subcutaneous implantations reveal a stronger host cell invasion in SNP hydrogels, resulting in increased vasculogenesis. Furthermore, time-dependent expression of different osteogenic factors reveals progressive differentiation of hMSCs in OMP, SNP, and SNP/OMP hydrogels. Our work demonstrates that endowing hydrogels with OMPs can induce, improve, and steer the formation of functional engineered living tissues, which holds potential for numerous biomedical applications, including tissue regeneration and organ replacement therapy.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Humanos , Diferenciação Celular , Engenharia Tecidual/métodos , Hidrogéis/farmacologia , Hipóxia/metabolismo , Oxigênio/metabolismo
12.
J Mol Recognit ; 36(7): e3024, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37158286

RESUMO

Based on the synergistic action of hydrogen bond and electrostatic interaction, provided by methacrylic acid and 2-aminoethyl ester hydrochloride (FM2), respectively, novel molecularly imprinted polymers (SA-MIPs) were designed to improve its selective recognition ability. Diclofenac sodium (DFC) was chosen as the template molecule of this study. The interaction and their recognition sites between two functional monomers and templates were confirmed by nuclear magnetic resonance hydrogen spectroscopy. Because of the synergistic action of hydrogen bond and electrostatic interaction, the imprinting factor (IF) of SA-MIPs (IF = 2.26) is superior to the corresponding monofunctional monomer imprinting materials (IF = 1.52, 1.20) and the materials using two functional monomers with an only single type of interaction (IF = 1.54, 1.75). The results of selective adsorption experiments indicate that the selective recognition ability of SA-MIPs is significantly better than that of the other four MIPs, and the difference in selectivity coefficient for methyl orange is the largest between SA-MIPs and the MIPs only using FM2, which is about 70 times. In addition, x-ray photoelectron spectroscopy was used to verify the interaction between SA-MIPs and the template. This work and its explanation of the interaction mechanism at the molecular level will be helpful for the rational design of novel MIPs with higher selectivity. Besides, SA-MIPs have good adsorption performance (37.75 mg/g) for DFC in aqueous solutions, which could be used as potential adsorption materials for the effective removal of DFC in the aquatic environment.


Assuntos
Impressão Molecular , Polímeros Molecularmente Impressos , Impressão Molecular/métodos , Polímeros/química , Ligação de Hidrogênio , Eletricidade Estática , Adsorção
13.
Int J Pharm ; 638: 122921, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37028575

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic is caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), resulting in a serious burden on public health and social economy worldwide. SARS-CoV-2 infection is mainly initialized in the nasopharyngeal cavity through the binding of viral spike (S) protein to human angiotensin-converting enzyme 2 (hACE2) receptors which are widely expressed in many human cells. Thus, blockade of the interaction between viral S protein and hACE2 receptor in the primary entry site is a promising prevention strategy for the management of COVID-19. Here we showed protein microparticles (PMPs) decorated with hACE2 could bind and neutralize SARS-CoV-2 S protein-expressing pseudovirus (PSV) and protect host cells from infection in vitro. In the hACE2 transgenic mouse model, administration of intranasal spray with hACE2-decorated PMPs markedly decreased the viral load of SARS-CoV-2 in the lungs though the inflammation was not attenuated significantly. Our results provided evidence for developing functionalized PMPs as a potential strategy for preventing emerging air-borne infectious pathogens, such as SARS-CoV-2 infection.


Assuntos
COVID-19 , Humanos , Camundongos , Animais , COVID-19/prevenção & controle , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2 , Glicoproteína da Espícula de Coronavírus/metabolismo , Camundongos Transgênicos
14.
World J Gastroenterol ; 29(9): 1446-1459, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36998425

RESUMO

Liver fibrosis is a wound-healing response following chronic liver injury caused by hepatitis virus infection, obesity, or excessive alcohol. It is a dynamic and reversible process characterized by the activation of hepatic stellate cells and excess accumulation of extracellular matrix. Advanced fibrosis could lead to cirrhosis and even liver cancer, which has become a significant health burden worldwide. Many studies have revealed that noncoding RNAs (ncRNAs), including microRNAs, long noncoding RNAs and circular RNAs, are involved in the pathogenesis and development of liver fibrosis by regulating signaling pathways including transforming growth factor-ß pathway, phosphatidylinositol 3-kinase/protein kinase B pathway, and Wnt/ß-catenin pathway. NcRNAs in serum or exosomes have been reported to tentatively applied in the diagnosis and staging of liver fibrosis and combined with elastography to improve the accuracy of diagnosis. NcRNAs mimics, ncRNAs in mesenchymal stem cell-derived exosomes, and lipid nanoparticles-encapsulated ncRNAs have become promising therapeutic approaches for the treatment of liver fibrosis. In this review, we update the latest knowledge on ncRNAs in the pathogenesis and progression of liver fibrosis, and discuss the potentials and challenges to use these ncRNAs for diagnosis, staging and treatment of liver fibrosis. All these will help us to develop a comprehensive understanding of the role of ncRNAs in liver fibrosis.


Assuntos
MicroRNAs , RNA Longo não Codificante , Humanos , RNA não Traduzido/genética , Cirrose Hepática/diagnóstico , Cirrose Hepática/genética , Cirrose Hepática/terapia , Fibrose , RNA Longo não Codificante/genética , Via de Sinalização Wnt
15.
Chem Commun (Camb) ; 59(15): 2102-2105, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36723180

RESUMO

C-O bond scission via photocatalysis is an important step in biomass depolymerization. Here, we demonstrate the scission of strong ether C-O bonds promoted by low-work-function Cd single atoms and clusters. Their loading on ZnS benefits C-H bond scission, thus weakening the C-O bond for chemical bond breaking.

16.
Anal Chem ; 94(50): 17577-17586, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36480745

RESUMO

Reliable characterization of binding affinities is crucial for selected aptamers. However, the limited repertoire of universal approaches to obtain the dissociation constant (KD) values often hinders the further development of aptamer-based applications. Herein, we present a competitive hybridization-based strategy to characterize aptamers using DNA origami-based chiral plasmonic assemblies as optical reporters. We incorporated aptamers and partial complementary strands blocking different regions of the aptamers into the reporters and measured the kinetic behaviors of the target binding to gain insights on aptamers' functional domains. We introduced a reference analyte and developed a thermodynamic model to obtain a relative dissociation constant of an aptamer-target pair. With this approach, we characterized RNA and DNA aptamers binding to small molecules with low and high affinities.


Assuntos
Aptâmeros de Nucleotídeos , Aptâmeros de Nucleotídeos/química , RNA/química , DNA/química , Sondas de DNA/química , Hibridização de Ácido Nucleico , Técnica de Seleção de Aptâmeros
17.
Anal Chem ; 94(48): 16720-16727, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36397197

RESUMO

Metal-organic frameworks (MOFs) have exhibited tremendous potential in the area of separation science. However, most of the developed MOF-based stationary phases contained only microporous structures and suffer from limited separation performance. Herein, homomesoporous MOFs with excellent mass transfer capability and strong thermodynamic interactions are first explored as the novel stationary phase for high-performance capillary electrochromatographic separations. As a proof of concept, noninterpenetrated mesoMOF-1 with uniform mesopore sizes (22.5 × 26.1 Å) and good stability was facilely grown on the inner surface of capillaries and applied as a homomesoporous MOF coating-based stationary phase for high-efficiency electrochromatographic separation. Seven types of analytes with different molecular dimensions were all baseline separated on a mesoMOF-1 coated column with high theoretical plate numbers and excellent repeatability, exhibiting significantly improved separation selectivity and column efficiency in comparison to a microporous HKUST-1 coated column. The maximum column efficiencies of the mesoMOF-1 coated column for substituted benzenes and halobenzenes reached up to 1.4 × 105 plates/m, and its mass loadability was also much higher than that of the HKUST-1 coated column. In addition, based on the analysis of adsorption kinetics and chromatographic retention behaviors, the interaction and retention mechanisms of different molecular-weight analytes on mesoMOF-1 coated stationary phases were systematically explored and disclosed in detail. These results indicate that the homomesoporous MOF-based stationary phase can effectively balance the kinetic diffusion (mass transfer capability) and thermodynamic interactions (the strength of adsorption interaction), having great potential for high-performance chromatographic separation.


Assuntos
Eletrocromatografia Capilar , Estruturas Metalorgânicas , Eletrocromatografia Capilar/métodos , Benzeno , Termodinâmica
18.
J Chromatogr A ; 1685: 463617, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36379197

RESUMO

To ensure drug safety, the quality monitoring of genotoxic impurities (GTIs) which have very trace content in medicine is important. Therefore, it should be established an efficient sample pretreatment method to extract GTIs to achieve specific enrichment. In this work, dummy template molecular imprinting technology (DMIT) was used as dummy template molecule (DTM) to substitute for the target molecule (TM) for established the pretreatment of the sample containing aromatic amine GTIs. A novel strategy for screening out DTM by calculation of computer simulation is established, where the binding energy between the template and functional monomer has the relatively lowest value (-9.60 kcal/mol). Then dummy template molecular imprinted polymer (DMIP) was prepared by bulk polymerization according to the molar ratio of template molecule-functional monomer-crosslinker = 1:4:8, the prepared DMIP exhibited the highest adsorption (Q = 8.6 mg/g) and good blotting effect (IF = 1.3) and can simultaneously adsorb three aromatic amine GTIs. The optimal adsorption conditions were obtained by conditional optimization of solid phase extraction (SPE). The solution of pH 7 was chosen as the loading condition, and methanol/acetic acid (90:10, v/v) was chosen as the elution condition. Finally, we determined 2, 6-dichloroaniline in diclofenac sodium at a 5 ppm level and p-toluidine as the TMs in torasemide sample at 10 ppm by using DMIT-based solid phase extraction and analysis by HPLC, it satisfied the quality control of GTIs in pharmaceutics. DMIT by this strategy has great potential in the sample preparation of GTIs.


Assuntos
Impressão Molecular , Polímeros Molecularmente Impressos , Aminas , Simulação por Computador , Impressão Molecular/métodos , Polímeros/química , Dano ao DNA
19.
Artigo em Inglês | MEDLINE | ID: mdl-36308942

RESUMO

The therapeutic function of traditional Chinese medicine (TCM) is based on the combination effect of multiple active ingredients. However, the current pharmacological studies mainly focus on the protein binding of the single component from TCM, which is difficult to explain the overall therapeutic mechanism. Thus in this work the equilibrium dialysis method combined with high performance liquid chromatography (HPLC) and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed to study the interactions between multi-components and protein. Firstly, the binding constants of seven different structural types of flavonoids with bovine serum albumin (BSA) were determined. The results showed that the binding affinity of flavones and flavonols with BSA was stronger than that of dihydroflavonoids, and the substitution of glycosides would reduce the binding affinity with BSA. The results of competitive displacement experiment showed that there existed competitive interactions among the four flavonoids (rutin, luteolin, hesperetin and kaempferol). The binding constants of flavonoids to BSA were significantly changed under the condition of multi-components coexistence. Especially, the binding constant of hesperetin to BSA increased from 9.46 × 104 L/mol to 1.49 × 106 L/mol under the coexistence of rutin. The results of fluorescence spectroscopy showed that the reason for competitive binding was that the four flavonoids were mainly bound to the IIA region of BSA. Finally, the method was successfully applied to study the binding of multiple components in Radix Scutellariae (RS) extract with BSA. Five flavonoids in RS extract were identified by UPLC-MS/MS, they had different degrees of binding to BSA, among which oroxylin A had the strongest binding degree. In conclusion, the equilibrium dialysis was reliable and sufficiently accurate for study of the interaction between multi-components or TCM extract and protein, which can provided a theoretical basis for the scientific explanation of the overall treatment mechanism of TCM.


Assuntos
Soroalbumina Bovina , Espectrometria de Massas em Tandem , Soroalbumina Bovina/química , Cromatografia Líquida , Diálise Renal , Flavonoides/química , Ligação Proteica , Espectrometria de Fluorescência/métodos , Rutina , Extratos Vegetais/metabolismo , Sítios de Ligação
20.
Skin Health Dis ; 2(3): e115, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36092264

RESUMO

Pilomatricoma (PM; calcifying epithelioma of Malherbe) is an uncommon adnexal tumour originating from the matrix of the hair follicles. Bullous appearance is a rare variant of PM, and its pathogenesis remains unclear. Here, we present a case of a 17-year-old girl with a pseudobullous PM on the right shoulder. Lymphatic dilatation and collagen disorder were histopathologically observed in this case, which may provide clues to elucidate the pathogenesis of pseudobullous PM.

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