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1.
Mol Pharm ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38920116

RESUMO

The continuous evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evaded the efficacy of previously developed antibodies and vaccines, thus remaining a significant global public health threat. Therefore, it is imperative to develop additional antibodies that are capable of neutralizing emerging variants. Nanobodies, as the smallest functional single-domain antibodies, exhibit enhanced stability and penetration ability, enabling them to recognize numerous concealed epitopes that are inaccessible to conventional antibodies. Herein, we constructed an immune library based on the immunization of alpaca with the S1 subunit of the SARS-CoV-2 spike protein, from which two nanobodies, Nb1 and Nb2, were selected using phage display technology for further characterization. Both nanobodies, with the binding residues residing within the receptor-binding domain (RBD) region of the spike, exhibited high affinity toward the S1 subunit. Moreover, they displayed cross-neutralizing activity against both wild-type SARS-CoV-2 and 10 ο variants, including BA.1, BA.2, BA.3, BA.5, BA.2.75, BF.7, BQ.1, EG.5.1, XBB.1.5, and JN.1. Molecular modeling and dynamics simulations predicted that both nanobodies interacted with the viral RBD through their complementarity determining region 1 (CDR1) and CDR2. These two nanobodies are novel tools for the development of therapeutic and diagnostic countermeasures targeting SARS-CoV-2 variants and potentially emerging coronaviruses.

2.
Nucleic Acids Res ; 50(D1): D1139-D1146, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34500460

RESUMO

MicroRNAs (miRNAs), which play critical roles in gene regulatory networks, have emerged as promising diagnostic and prognostic biomarkers for human cancer. In particular, circulating miRNAs that are secreted into circulation exist in remarkably stable forms, and have enormous potential to be leveraged as non-invasive biomarkers for early cancer detection. Novel and user-friendly tools are desperately needed to facilitate data mining of the vast amount of miRNA expression data from The Cancer Genome Atlas (TCGA) and large-scale circulating miRNA profiling studies. To fill this void, we developed CancerMIRNome, a comprehensive database for the interactive analysis and visualization of miRNA expression profiles based on 10 554 samples from 33 TCGA projects and 28 633 samples from 40 public circulating miRNome datasets. A series of cutting-edge bioinformatics tools and machine learning algorithms have been packaged in CancerMIRNome, allowing for the pan-cancer analysis of a miRNA of interest across multiple cancer types and the comprehensive analysis of miRNome profiles to identify dysregulated miRNAs and develop diagnostic or prognostic signatures. The data analysis and visualization modules will greatly facilitate the exploit of the valuable resources and promote translational application of miRNA biomarkers in cancer. The CancerMIRNome database is publicly available at http://bioinfo.jialab-ucr.org/CancerMIRNome.


Assuntos
Biomarcadores Tumorais/genética , Bases de Dados Genéticas , MicroRNAs/genética , Neoplasias/genética , Biomarcadores Tumorais/classificação , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/genética , Humanos , MicroRNAs/classificação , Neoplasias/classificação
3.
Anal Chem ; 95(23): 9043-9051, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37262441

RESUMO

Smart materials can dynamically and reversibly change their structures and functions in response to external stimuli. In this study, we designed a smart magnetic composite (MNP-pSPA-b-pNIPAm) with a triple response to ultraviolet (UV) light, pH, and temperature. Relying on the response of spiropyranyl acrylate (SPA) and N-isopropylacrylamide (NIPAm) to external stimuli (light, pH, and temperature), MNP-pSPA-b-pNIPAm was used for the controlled capture and release of phosphopeptides. The established phosphopeptide enrichment platform exhibits high sensitivity (detection limit of 0.04 fmol), high selectivity (BSA/ß-casein, 1000:1), and good reusability (6 cycles). In addition, the method was also applied to the enrichment of phosphopeptides in real samples (skim milk, human saliva, and serum), demonstrating the feasibility of this method for phosphoproteomic analysis. After enriching from human nonsmall cell lung cancer cell (A549) lysates with MNP-pSPA-b-pNIPAm, 2595 phosphopeptides corresponding to 2281 phosphoproteins were identified. The novel responsive enrichment probe is highly specific for phosphoproteomic analysis and provides an effective method for studying the significance of protein phosphorylation in complex biological samples.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Fosfopeptídeos/análise , Temperatura , Fenômenos Magnéticos , Concentração de Íons de Hidrogênio , Titânio/química
4.
Chemistry ; 29(37): e202300933, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37040176

RESUMO

Bulk chemical 2-methyl-2-butene, one of the main C5 distillates of the petrochemical industry, has scarcely been utilized directly in synthesizing high-value-added fine chemicals. Herein, we use 2-methyl-2-butene as the starting material to develop a palladium-catalyzed highly site- and regio-selective C-3 dehydrogenation reverse prenylation of indoles. This synthetic method features mild reaction conditions, a broad substrate scope, atom- and step-economies.

5.
Molecules ; 28(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36985470

RESUMO

5,6-Dihydrophenanthridines are common aza heterocycle frameworks of natural products and pharmaceuticals. Herein, we reported the first palladium-catalyzed intramolecular C-H/C-H dehydrogenative coupling reaction of two simple arenes to generate 5,6-dihydrophenanthridines. The approach features a broad substrate scope and good tolerance of functional groups, offering an efficient alternative synthesis route for important 5,6-dihydrophenanthridine compounds.

6.
Eur J Nucl Med Mol Imaging ; 49(12): 4109-4121, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35732973

RESUMO

OBJECTIVE: To evaluate the diagnostic accuracy of computed tomography pulmonary angiography (CTPA) and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) for pulmonary artery (PA) masses. METHODS: Of 2889 patients with PA filling defects of PA on CTPA, 79 consecutive patients suspicious for PA malignancy who subsequently underwent 18F-FDG PET/CT were enrolled. All masses were diagnosed on the basis of pathological findings or clinical imaging follow-up. For each mass, morphological CT signs, standardized uptake value (SUVmax and SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) on 18F-FDG PET/CT were used as diagnostic markers. RESULTS: Expansive growth, irregular margin, invasion, CT contrast uptake, and wall eclipse sign were strongly associated with the malignant nature of masses. The coexistence of at least 5 CT signs perfectly identified malignant masses, whereas the detection of no more than 4 CT signs did not accurately discriminate between the natures of masses. Mean SUVmax, SUVmean, MTV, and TLG values were significantly higher in malignant masses compared to those in benign masses. The diagnostic accuracy of 18F-FDG PET/CT parameters (SUV, MTV, and TLG) was excellent in detecting malignant masses. Among patients with 3 or 4 pathological CT signs, SUVmax > 3.4 significantly increased the identification of malignancies. CONCLUSIONS: CTPA is a useful imaging modality for diagnosing PA masses, especially when at least 5 abnormal CT signs are identified. Similarly, 18F-FDG PET/CT accurately identified malignant masses and provided additional valuable information on diagnostic uncertainties after CTPA.


Assuntos
Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Angiografia , Fluordesoxiglucose F18/metabolismo , Glicólise , Prognóstico , Artéria Pulmonar/diagnóstico por imagem , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Carga Tumoral
7.
Chemistry ; 28(39): e202200981, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35487846

RESUMO

A new class of electrophilic monofluoromethylselenolation reagents, Se-(fluoromethyl) benzenesulfonoselenoates, has been developed. They can be readily prepared from sodium benzenesulfinates, Se powder and ClCFH2 in one step under mild reaction conditions. Se-(fluoromethyl) benzenesulfonoselenoates are efficient electrophilic monofluoromethylselenolation reagents for a wide range of nucleophiles including indole, 6-azaindole, pyrrole, thiophene, electron-rich arene, aryl boronic acid and alkyne. The monofluoromethylselenolation approach features mild and environmentally friendly reaction conditions, good tolerance of various functional groups, and broad substrate scope.


Assuntos
Alcinos , Ácidos Borônicos , Elétrons , Indicadores e Reagentes
8.
J Org Chem ; 87(9): 5730-5743, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35471034

RESUMO

An efficient Pd-catalyzed C(sp3)-H selective iodination of 8-methylquinolines is reported herein for the first time. Because of the versatility of organic iodides, the method offers a facile access to various C8-substituted quinolines. By slightly switching the reaction conditions, an efficient C(sp3)-H acetoxylation of 8-methylquinolines has also been enabled. Both approaches feature mild reaction conditions, good tolerance of functional groups, and a broad substrate scope.

9.
J Org Chem ; 87(10): 6573-6587, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35522737

RESUMO

A new chemistry of azo compounds, that is, addition of free radicals generated in situ to access various acyl hydrazides, has been developed. The protocol provides a novel strategy for the synthesis of valuable acyl hydrazides. The transformation features mild reaction conditions, good tolerance of functional groups, and a broad substrate scope. In view of the importance of acyl hydrazides in functional materials and medicinal chemistry, this approach would find broad applications.


Assuntos
Ésteres , Hidrazinas , Ésteres/química , Radicais Livres , Hidrazinas/química
10.
Analyst ; 147(20): 4553-4561, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36102749

RESUMO

A hydrophilic interaction chromatography (HILIC) strategy is considered as an efficient strategy for efficient glycopeptide enrichment. Here, a novel hydrophilic material (denoted as magCDP@Ada-MSA) was constructed through host-guest interaction between crosslinked ß-cyclodextrin (ß-CD) polymers and mercaptosuccinic acid (MSA) derived adamantane. On the one hand, crosslinked ß-CD polymers have great hydrophilicity due to their abundant hydrophilic hydroxyl groups. On the other hand, the hydrophilic functional molecule MSA was introduced into crosslinked ß-CD polymers through host-guest interaction for further hydrophilic modification of the material. Hydroxyl groups in crosslinked ß-CD polymers and carboxyl groups in MSA together endow the material with excellent hydrophilicity and good affinity toward glycopeptides. The prepared hydrophilic material demonstrated rapid magnetic separation (within 5 s) and reusability (at least 10 cycles). Thanks to the above advantages, magCDP@Ada-MSA showed satisfactory performance for the specific enrichment of glycopeptides (selectivity, 1 : 500 molar ratios of HRP/BSA and sensitivity, 0.1 fmol µL-1). Moreover, magCDP@Ada-MSA was successfully applied for selective glycopeptide enrichment from complex biological samples (human serum and saliva).


Assuntos
Adamantano , beta-Ciclodextrinas , Celulose , Ciclodextrinas , Glicopeptídeos/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Polímeros/química , Tiomalatos
11.
Eur Arch Psychiatry Clin Neurosci ; 272(4): 633-642, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35037116

RESUMO

The upregulation of immune and inflammatory response may play a role in the negative symptoms of schizophrenia. Berberine is an effective drug with anti-inflammatory property, and may be beneficial for the treatment of negative symptoms. The aim of this study is to test this hypothesis through a randomized, double-blind, placebo-controlled, clinical trial. Eligible patients with schizophrenia were randomized to receive placebo or berberine (900 mg/day) for 8 weeks as adjunctive treatment to single atypical antipsychotic drug. The Positive and Negative Syndrome Scale (PANSS) was used to evaluate clinical symptoms at three time points (baseline, 4th and 8th week). Blood samples were collected at the above three time points to determine the concentrations of inflammatory markers including interleukin-1ß (IL-1ß), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP). 59 patients with intention-to-treat were analyzed, 32 in the berberine group and 27 in the placebo group. From the baseline to the 8th week, berberine treatment significantly improved the negative symptom subscale of PANSS (F = 18.981; p < 0.001). From the baseline to the 8th week, the plasma CRP concentration decreased in the berberine group, while increased in the placebo group (F = 5.373; p = 0.024). Furthermore, in the berberine group, the change of CRP concentration was significantly positively correlated with the change of PANSS negative symptom subscale within 8 weeks (r = 0.56; p = 0.002). There was no significant difference in adverse events between the two groups (p's > 0.05). Our study suggests that berberine treatment is well tolerated in patients with schizophrenia. Berberine may improve negative symptoms through anti-inflammatory effect.Trial registration: Clinicaltrials.gov identifier: NCT03548155.


Assuntos
Antipsicóticos , Berberina , Esquizofrenia , Antipsicóticos/uso terapêutico , Berberina/uso terapêutico , Proteína C-Reativa , Método Duplo-Cego , Quimioterapia Combinada , Humanos , Escalas de Graduação Psiquiátrica , Esquizofrenia/diagnóstico , Esquizofrenia/tratamento farmacológico , Resultado do Tratamento
12.
Eur Heart J ; 42(9): 919-933, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33532862

RESUMO

AIMS: While most patients with myocardial infarction (MI) have underlying coronary atherosclerosis, not all patients with coronary artery disease (CAD) develop MI. We sought to address the hypothesis that some of the genetic factors which establish atherosclerosis may be distinct from those that predispose to vulnerable plaques and thrombus formation. METHODS AND RESULTS: We carried out a genome-wide association study for MI in the UK Biobank (n∼472 000), followed by a meta-analysis with summary statistics from the CARDIoGRAMplusC4D Consortium (n∼167 000). Multiple independent replication analyses and functional approaches were used to prioritize loci and evaluate positional candidate genes. Eight novel regions were identified for MI at the genome wide significance level, of which effect sizes at six loci were more robust for MI than for CAD without the presence of MI. Confirmatory evidence for association of a locus on chromosome 1p21.3 harbouring choline-like transporter 3 (SLC44A3) with MI in the context of CAD, but not with coronary atherosclerosis itself, was obtained in Biobank Japan (n∼165 000) and 16 independent angiography-based cohorts (n∼27 000). Follow-up analyses did not reveal association of the SLC44A3 locus with CAD risk factors, biomarkers of coagulation, other thrombotic diseases, or plasma levels of a broad array of metabolites, including choline, trimethylamine N-oxide, and betaine. However, aortic expression of SLC44A3 was increased in carriers of the MI risk allele at chromosome 1p21.3, increased in ischaemic (vs. non-diseased) coronary arteries, up-regulated in human aortic endothelial cells treated with interleukin-1ß (vs. vehicle), and associated with smooth muscle cell migration in vitro. CONCLUSIONS: A large-scale analysis comprising ∼831 000 subjects revealed novel genetic determinants of MI and implicated SLC44A3 in the pathophysiology of vulnerable plaques.


Assuntos
Doença da Artéria Coronariana , Infarto do Miocárdio , Doença da Artéria Coronariana/genética , Células Endoteliais , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Humanos , Japão , Infarto do Miocárdio/genética , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco
13.
Curr Psychol ; : 1-13, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36277265

RESUMO

Interindividual differences in personal values are prevalent both within and across societies. Interindividual differences in personal value and the relationships with mental health disorders and life satisfaction remain to be holistically considered, especially in China. The present study aims to characterize personal value profiles based on Schwartz's theory model and to examine differences in several mental health-related disorders and life satisfaction potentially across these profiles. Using convenience sampling, a sample of 8,540 Chinese college students (Mage = 18.89, SDage = 2.02, 57.7% male) from three universities completed a questionnaire assessing personal values, internalizing problems, externalizing problems, substance disorders, crime/violence, and life satisfaction. The latent profile analysis identified five personal value profiles, which were labelled as traditional social orientation, open personal orientation, open social orientation, moderate traditional social orientation, and average. Chinese college students in the three social orientation profiles reported low mental health disorders and high life satisfaction. In contrast, students in the personal orientation profile reported high mental health disorders and low life satisfaction. The results indicate the heterogeneity of Chinese college students' personal values and the positive relationship of social-oriented values with mental health and life satisfaction in collectivist cultures.

14.
Pharmacol Res ; 165: 105439, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33493658

RESUMO

The gut microbiota is recognized as a promising therapeutic target for anxiety. Berberine (BBR) has shown efficacy in the treatment of diseases such as postmenopausal osteoporosis, obesity, and type 2 diabetes through regulating the gut microbiota. However, the effects of BBR on postmenopausal anxiety are still unclear. The purpose of the study is to test whether BBR ameliorates anxiety by modulating intestinal microbiota under estrogen-deficient conditions. Experimental anxiety was established in specific pathogen-free (SPF) ovariectomized (OVX) rats, which were then treated with BBR for 4 weeks before undergoing behavioral tests. Open field and elevated plus maze tests demonstrated that BBR treatment significantly ameliorated anxiety-like behaviors of OVX rats compared with vehicle-treated counterparts. Moreover, as demonstrated by 16S rRNA sequencing and liquid chromatography/mass spectrometry (LC/MS) analysis, BBR-treated OVX rats harbored a higher abundance of beneficial gut microbes, such as Bacteroides, Bifidobacterium, Lactobacillus, and Akkermansia, and exhibited increased equol generation. Notably, gavage feeding of BBR had no significant anti-anxiety effects on germ-free (GF) rats that underwent ovariectomy, whereas GF rats transplanted with fecal microbiota from SPF rats substantially phenocopied the donor rats in terms of anxiety-like symptoms and isoflavone levels. This study indicates that the gut microbiota is critical in the treatment of ovariectomy-aggravated anxiety, and that BBR modulation of the gut microbiota is a promising therapeutic strategy for treating postmenopausal symptoms of anxiety.


Assuntos
Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Berberina/uso terapêutico , Equol/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Ovariectomia/efeitos adversos , Animais , Ansiedade/etiologia , Berberina/farmacologia , Transplante de Microbiota Fecal/métodos , Feminino , Microbioma Gastrointestinal/fisiologia , Ratos , Ratos Sprague-Dawley
15.
Acta Pharmacol Sin ; 42(11): 1821-1833, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33558654

RESUMO

Accumulating evidence shows that agents targeting gut dysbiosis are effective for improving symptoms of irritable bowel syndrome (IBS). However, the potential mechanisms remain unclear. In this study we investigated the effects of berberine on the microbiota-gut-brain axis in two rat models of visceral hypersensitivity, i.e., specific pathogen-free SD rats subjected to chronic water avoidance stress (WAS) and treated with berberine (200 mg· kg-1 ·d-1, ig, for 10 days) as well as germ-free (GF) rats subjected to fecal microbiota transplantation (FMT) from a patient with IBS (designated IBS-FMT) and treated with berberine (200 mg· kg-1 ·d-1, ig, for 2 weeks). Before the rats were sacrificed, visceral sensation and depressive behaviors were evaluated. Then colonic tryptase was measured and microglial activation in the dorsal lumbar spinal cord was assessed. The fecal microbiota was profiled using 16S rRNA sequencing, and short chain fatty acids (SCFAs) were measured. We showed that berberine treatment significantly alleviated chronic WAS-induced visceral hypersensitivity and activation of colonic mast cells and microglia in the dorsal lumbar spinal cord. Transfer of fecal samples from berberine-treated stressed donors to GF rats protected against acute WAS. FMT from a patient with IBS induced visceral hypersensitivity and pro-inflammatory phenotype in microglia, while berberine treatment reversed the microglial activation and altered microbial composition and function and SCFA profiles in stools of IBS-FMT rats. We demonstrated that berberine did not directly influence LPS-induced microglial activation in vitro. In both models, several SCFA-producing genera were enriched by berberine treatment, and positively correlated to the morphological parameters of microglia. In conclusion, activation of microglia in the dorsal lumbar spinal cord was involved in the pathogenesis of IBS caused by dysregulation of the microbiota-gut-brain axis, and the berberine-altered gut microbiome mediated the modulatory effects of the agent on microglial activation and visceral hypersensitivity, providing a potential option for the treatment of IBS.


Assuntos
Berberina/uso terapêutico , Eixo Encéfalo-Intestino/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Microglia/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Dor Visceral/tratamento farmacológico , Animais , Berberina/farmacologia , Eixo Encéfalo-Intestino/fisiologia , Linhagem Celular , Transplante de Microbiota Fecal/métodos , Microbioma Gastrointestinal/fisiologia , Humanos , Síndrome do Intestino Irritável/tratamento farmacológico , Síndrome do Intestino Irritável/metabolismo , Masculino , Camundongos , Microglia/metabolismo , Ratos , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/metabolismo , Dor Visceral/metabolismo
16.
Mikrochim Acta ; 188(11): 384, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34664135

RESUMO

As an ideal substitute for traditional organic fluorescent dyes or up-conversion nanomaterials, copper nanoclusters (CuNCs) have developed rapidly and have been involved in exciting achievements in versatile applications. The emergence of novel CuNCs composites improves the poor stability and fluorescence intensity of CuNCs. With this in mind, great efforts have been made to develop a wide variety of CuNCs composites, and impressive progress has been made in the past few years. In this review, we systematically summarize absorption, fluorescence, electrochemiluminescence, and catalytic properties and focus on the multiple factors that affect the fluorescence properties of CuNCs. The fluorescence properties of CuNCs are discussed from the point of view of core size, surface ligands, self-assembly, metal defects, pH, solvent, ions, metal doping, and confinement effect. Especially, we illustrate the research progress and representative applications of CuNCs composites in bio-related fields, which have received considerable interests in the past years. Additionally, the sensing mechanism of CuNCs composites is highlighted. Finally, we summarize current challenges and look forward to the future development of CuNCs composites. Schematic diagram of the categories, possible sensing mechanisms, and bio-related applications of copper nanoclusters composites.


Assuntos
Técnicas Biossensoriais/métodos , Cobre/química , Nanopartículas Metálicas/química , Nanoestruturas
17.
Anal Chem ; 92(3): 2680-2689, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31977188

RESUMO

Protein glycosylation and phosphorylation are two important protein post-translational modifications. Mass spectrometry (MS) has been proved to be a powerful technique in comprehensive characterization of protein glycosylation and phosphorylation; however, the complexity of biological matrices and weak ionization efficiency bring a big challenge. Capturing glycopeptides and phosphopeptides from complicated biological samples is indispensable before MS determinations. In this study, a bifunctional gallium ion immobilized magnetic pertriflated pillar[5]arene supramolecular-organic framework (magOTfP5SOF-Ga3+) was designed for the one-step simultaneous enrichment of glycopeptides and phosphopeptides. Thanks to the abundant sulfonic acid groups, the material owns strong hydrophilicity and leads to hydrophilic interaction chromatography for glycopeptides enrichment. Simultaneously, the high loading amount of gallium ion provides immobilized metal ion affinity for phosphopeptides enrichment. The established platform possesses quick magnetic response performance, high sensitivity (detection limits as low as 0.1 fmol and 0.05 fmol for glycopeptides and phosphopeptides, respectively), and good reusability. In addition, the method was applied to the determination of glycopeptides and phosphopeptides in clinical specimens, cell lysates, and mouse liver tissue samples, demonstrating its highly sensitive and specific glycoproteomics and phosphorproteomics analysis in complex biosamples.


Assuntos
Glicopeptídeos/síntese química , Estruturas Metalorgânicas/química , Nanopartículas/química , Fosfopeptídeos/síntese química , Calixarenos/química , Gálio/química , Glicopeptídeos/sangue , Glicosilação , Humanos , Substâncias Macromoleculares/química , Fenômenos Magnéticos , Tamanho da Partícula , Fosfopeptídeos/sangue , Fosforilação , Propriedades de Superfície
18.
Anal Chem ; 92(5): 4137-4145, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32027489

RESUMO

A total of 15 representative organophosphorus pesticides (OPPs), a class of water pollutants causing serious global concerns, have been sensitively quantified by internal extractive electrospray ionization mass spectrometry (iEESI-MS) after enrichment with Fe3O4-ZrO2 innovatively synthesized in our lab by a one step coprecipitation method. For the premium enrichment, the amounts of Fe3O4-ZrO2, pH value, adsorption time, type and volume of desorption solvent, and shaking time of desorption were systematically optimized. Under optimized conditions, the proposed method provided low limits of detection (LODs) of 0.14-16.39 ng L-1 with relative standard deviations (RSDs) of less than 8.7%. A wide linear response range of about 4 orders of magnitude was achieved with linear coefficients (R2) of 0.9921-0.9999 for all the analytes tested. The present method also provided good recoveries (85.4-105.9%) with acceptable precision (RSDs < 7.2%) in spiked environmental water samples. Furthermore, multiple analytes including dimethoate, omethoate, etc. were simultaneously detected in a single sample run, which was accomplished within 1 min, resulting in significantly improved analytical throughput for quantitative analysis of bulk amounts of samples. The experimental results demonstrated that Fe3O4-ZrO2-iEESI-MS provided advantages, including high sensitivity, high speed, and reasonable selectivity for the detection of OPPs, showing potential applications in environmental water sample analysis and environmental science.


Assuntos
Magnetismo , Nanocompostos/química , Praguicidas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Poluentes Químicos da Água/análise , Zircônio/química , Óxido Ferroso-Férrico/química , Água Doce/análise , Concentração de Íons de Hidrogênio , Limite de Detecção , Compostos Organofosforados/análise , Compostos Organofosforados/isolamento & purificação , Praguicidas/isolamento & purificação , Extração em Fase Sólida , Poluentes Químicos da Água/isolamento & purificação
19.
Exp Dermatol ; 29(5): 467-476, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32170969

RESUMO

Melanogenesis, migration and proliferation of melanocytes are important factors that determine the hair colours of mammals. MicroRNAs (miRNAs) have been shown to be closely related to these processes. In melanocytes of alpacas, insulin-like growth factor 1 (IGF1) has been shown to improve melanogenesis through the cyclic AMP (cAMP) pathway. miR-379 was predicted to target insulin-like growth factor (IGF) receptor 1 (IGF1R), which binds to IGF1. Therefore, we hypothesized that miR-379 could mediate melanogenesis, migration and proliferation of melanocytes. Here, we report that miR-379 was highly expressed in alpaca melanocytes. Subsequent overexpression of miR-379 in alpaca melanocytes led to the generation of the phenotype of melanogenesis, proliferation and migration. In addition, the expression of genes related to these phenotypes in melanocytes was detected. Our results showed that miR-379 targets IGF1R in melanocytes. The overexpression of miR-379 stimulated dendrite extension or elongation and limited the perinuclear distribution of melanin, but inhibited melanogenesis via cAMP response element (CRE)-binding protein (CREB)/microphthalmia-associated transcription factor (MITF) pathway. miR-379 attenuated melanocyte migration by downregulating the focal adhesion kinase (FAK) and enhanced melanocyte proliferation by upregulating protein kinase B (AKT). These observations suggest the involvement of miR-379 in the physiological regulation of melanocytes, mediated by targeting IGF1R on insulin receptor (IR) compensation and subsequent crosstalk.


Assuntos
Camelídeos Americanos/metabolismo , Melanócitos/metabolismo , MicroRNAs/biossíntese , Pigmentação , Receptor IGF Tipo 1/biossíntese , Regiões 3' não Traduzidas , Fator 2 Ativador da Transcrição/metabolismo , Animais , Movimento Celular , Proliferação de Células , Melaninas/metabolismo , Camundongos , MicroRNAs/genética , Fator de Transcrição Associado à Microftalmia/metabolismo , Fenótipo , Reação em Cadeia da Polimerase , Ligação Proteica , Receptor de Insulina/metabolismo
20.
Org Biomol Chem ; 18(30): 5918-5926, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32691819

RESUMO

We report herein an efficient, economical, and scalable trifluoromethylthiolation of aldehydes to generate trifluoromethylthioesters via a visible light-promoted radical process. The transformation features cheap reagents, simple operation, a broad substrate scope, and especially no metal involved in the reaction. Trifluoromethylthiolations of several complex aldehyde-containing bioactive compounds have been realized; thus the approach has the potential to be an important tool for the late-stage functionalization of advanced synthetic intermediates and bioactive molecules, and should have many applications in medicinal chemistry.

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