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1.
Rapid Commun Mass Spectrom ; 37(14): e9529, 2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-37125446

RESUMO

RATIONALE: Thymoma is a rare malignant tumor but it is the most common primary tumor of the anterior mediastinum. The current imaging methods for thymoma screening suffer from false positive rate problems, and thymoma pathogenesis remains elusive. Study of thymoma metabolic characteristics could provide clues for improving the diagnosis and understanding the pathogenesis of thymoma. METHODS: Metabolic profiling of plasma from thymoma and thymic hyperplasia patients was performed using ultrahigh-performance liquid chromatography combined with high-resolution mass spectrometry in both positive and negative ionization modes. After pre- and post-processing, the dataset was divided into three age groups and statistical analysis was performed to select differential metabolites of thymoma. For feature identification, experimental tandem mass spectra were matched to those of databases and available chemical standards, and also manually annotated with plausible chemical structures to ensure high identification confidence. RESULTS: A total of 47 differential metabolites were identified in thymoma. Significantly higher levels of histidine, sphinganine 1-phosphate, lactic acid dimer, phenylacetylglutamine, LPC (18:3) and LPC (16:1), and significantly lower levels of phenylalanine, indole-3-propionic acid (IPA), hippuric acid and mesobilirubinogen were associated with thymoma. Tryptophan level in thymoma-associated myasthenia gravis (TAMG) was significantly lower than that of the MG(-) group. IPA and hippuric acid abundances exhibited increasing trends from indolent to aggressive thymoma. CONCLUSIONS: Our study revealed aberrant aromatic amino acid metabolism and fatty acid oxidation might be associated with thymoma. The identified unique metabolic characteristics of thymoma may provide valuable information for study of the molecular mechanism of thymoma pathogenesis, and improvement of diagnosis and discovery of new therapeutic strategies for thymoma.


Assuntos
Timoma , Hiperplasia do Timo , Neoplasias do Timo , Humanos , Timoma/complicações , Timoma/diagnóstico , Timoma/patologia , Hiperplasia do Timo/complicações , Hiperplasia do Timo/patologia , Neoplasias do Timo/complicações , Neoplasias do Timo/diagnóstico , Neoplasias do Timo/patologia , Metabolômica , Espectrometria de Massas , Cromatografia Líquida
2.
Int J Mol Sci ; 24(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36675016

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in most parts of the world. Although there is no first-line drug approved for the treatment of NAFLD, polyene phosphatidylcholine (PPC) is used by clinicians to treat NAFLD patients. This study aimed to evaluate the efficacy of PPC on a mice model of NAFLD, and to study the PPC's mechanism of action. The mice were fed a choline-deficient, L-amino acid-defined (CDAA) diet to induce NAFLD and were subsequently treated with PPC. The treatment effects were evaluated by the liver index, histopathological examination, and routine blood chemistry analyses. Lipidomics and metabolomics analyses of 54 samples were carried out using ultraperformance liquid chromatography (UPLC) coupled to a mass spectrometer to select for changes in metabolites associated with CDAA diet-induced NAFLD and the effects of PPC treatment. The intestinal flora of mice were extracted for gene sequencing to find differences before and after the induction of NAFLD and PPC treatment. PPC significantly improved the CDAA diet-induced NAFLD condition in mice. A total of 19 metabolites including 5 polar metabolites and 14 lipids showed marked changes. In addition, significant differences in the abundance of Lactobacillus were associated with NAFLD. We inferred that the protective therapeutic effect of PPC on the liver was related to the supplement of phosphatidylcholine, lysophosphatidylcholine, and sphingomyelin (PC, LPC, and SM, resectively) and acylcarnitine metabolism. This study developed a methodology for exploring the pathogenesis of NAFLD and can be extended to other therapeutic agents for treating NAFLD.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Lipidômica , Fígado/metabolismo , Fosfatidilcolinas/metabolismo , Camundongos Endogâmicos C57BL
3.
J Proteome Res ; 21(8): 2011-2022, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35856400

RESUMO

Non-small cell lung cancer (NSCLC) is the prevalent histological subtype of lung cancer. In this study, we performed ultraperformance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS)-based metabolic profiling of 227 tissue samples from 79 lung cancer patients with adenocarcinoma (AC) or squamous cell carcinoma (SCC). Orthogonal partial least squares-discriminant analysis (oPLS-DA) analyses showed that AC, SCC, and NSCLC tumors were discriminated from adjacent noncancerous tissue (ANT) and distant noncancerous tissue (DNT) samples with good accuracies (91.3, 100, and 88.3%), sensitivities (85.7, 100, and 83.9%), and specificities (94.3, 100, and 90.7%), using 12, 4, and 7 discriminant metabolites, respectively. The discriminant panel for AC detection included valine, sphingosine, glutamic acid γ-methyl ester, and lysophosphatidylcholine (LPC) (16:0), levels of which in tumor tissues were significantly altered. Valine, sphingosine, LPC (18:1), and leucine derivatives were used for SCC detection. The discrimination between AC and SCC had 96.8% accuracy, 98.2% sensitivity, and 85.7% specificity using a five-metabolite panel, of which valine and creatine had significant differences. The classification models were further verified with external validation sets, showing a promising prospect for NSCLC tissue detection and subtyping.


Assuntos
Adenocarcinoma , Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Espectrometria de Massas , Metabolômica/métodos , Esfingosina , Valina
4.
Langmuir ; 38(32): 9967-9973, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35916597

RESUMO

Integrated smart clothing with photothermal conversion and thermosensing functions is highly desired for next-generation smart wearable applications. Conducting polymer is a promising material that possesses efficient photothermal conversion performance, great sensitivity to temperature change, and excellent processing properties. In this study, we report a new wearable material using the conducting polymer polypyrrole (PPy) as a photothermal and thermosensing layer and nonwoven fabric as flexible textiles to fabricate integrated PPy-based smart clothing (IPSC). The surface temperature of the prepared IPSC can be as high as 68.4 °C with 808 nm near-infrared (NIR) irradiation at a power destiny of 1 kW/m2. Meanwhile, a temperature resolution of 1 °C can be achieved for IPSC. These superiorities are in favor of fabricating multifunctional smart wearables to satisfy the needs in future life.


Assuntos
Materiais Inteligentes , Dispositivos Eletrônicos Vestíveis , Polímeros , Pirróis , Sensação Térmica
5.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36232383

RESUMO

Abnormal tryptophan metabolism is linked to cancer and neurodegenerative diseases, and tryptophan metabolites have been reported as potential prostate cancer (PCa) biomarkers. However, little is known about the bioactivities of tryptophan metabolites on PCa cell growth. In this study, MTT and transwell assays were used to study the cytotoxicities of 13 major tryptophan metabolites on PCa and normal prostate epithelial cell lines. Ultraperformance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) was used to analyze metabolic changes in cells treated with tryptamine. Flow cytometry, confocal imaging, and Western blot were used to test the apoptosis induced by tryptamine. It was shown that tryptamine had obvious inhibitory effects on PCa cell lines PC-3 and LNCaP, stronger than those on the normal prostate cell line RWPE-1. Tryptamine was further shown to induce apoptosis and inhibit PC-3 cell migration. Metabolic changes including amino acid metabolism related to cell proliferation and metastasis were found in PC-3 cells treated with tryptamine. Furthermore, a PC-3 xenograft mouse model was used to study the effect of tryptamine in vivo. The intratumoral injection of tryptamine was demonstrated to significantly reduce the tumor growth and tumor sizes in vivo; however, intraperitoneal treatment resulted in increased tumor growth. Such dual effects in vivo advanced our understanding of the bioactivity of tryptamine in regulating prostate tumor development, in addition to its major role as a neuromodulator.


Assuntos
Próstata , Neoplasias da Próstata , Animais , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Projetos Piloto , Próstata/patologia , Neoplasias da Próstata/metabolismo , Triptaminas/farmacologia , Triptofano/metabolismo , Triptofano/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Apoptosis ; 26(1-2): 111-131, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33389358

RESUMO

H2S is actual an endogenous signaling gas molecule and involved in a range of cell physiological processes. However, the mechanism of endogenous H2S regulating autophagy and apoptosis has not been thoroughly investigated. Here, we try to address this issue by using a H2S probe, (E)-2-(4-(4-(7-(diethylamino)-2-oxo-2H-chromene-3-carbonyl)-piperazin-1-yl)-styryl)-1, 3, 3-trimethyl-3H-indol-1-ium iodide (CPC), which could react with endogenous H2S. Herein, we reported that CPC inhibited autophagy and decreased the expression and activity of NF-E2-related factor 2 (Nrf2), then induced cell apoptosis. CPC inhibited autophagy and promoted apoptosis by inhibiting Nrf2 activation, which was H2S dependent. Furthermore, we found that CPC inhibited Nrf2 nucleus translocation by inhibiting glutathionylation of Kelch-like ECH-associated protein 1 (Keap1) at the Cys434 residue. CPC also inhibited various cancer cell growth, but had no effect on normal cell growth in vitro, and inhibited A549 cancer growth, but did not affect normal angiogenesis in vivo. Therefore, we not only found a new inhibitor of autophagy and Nrf2, but also suggested a novel mechanism that endogenous H2S could regulate autophagy, apoptosis and Nrf2 activity through regulating glutathionylation of Keap1 at the Cys434 residue.


Assuntos
Apoptose , Autofagia , Glutationa/metabolismo , Sulfeto de Hidrogênio/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/química , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Motivos de Aminoácidos , Linhagem Celular , Cisteína/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo
7.
J Proteome Res ; 19(1): 144-152, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31621328

RESUMO

The most common cause of death in cystic fibrosis (CF) patients is progressive lung function decline, which is punctuated by acute pulmonary exacerbations (APEs). A major challenge is to discover biomarkers for detecting an oncoming APE and allow for pre-emptive clinical interventions. Metabolic profiling of exhaled breath condensate (EBC) samples collected from CF patients before, during, and after APEs and under stable conditions (n = 210) was performed using ultraperformance liquid chromatography (UPLC) coupled to Orbitrap mass spectrometry (MS). Negative ion mode MS data showed that classification between metabolic profiles from "pre-APE" (pending APE before the CF patient had any signs of illness) and stable CF samples was possible with good sensitivities (85.7 and 89.5%), specificities (88.4 and 84.1%), and accuracies (87.7 and 85.7%) for pediatric and adult patients, respectively. Improved classification performance was achieved by combining positive with negative ion mode data. Discriminant metabolites included two potential biomarkers identified in a previous pilot study: lactic acid and 4-hydroxycyclohexylcarboxylic acid. Some of the discriminant metabolites had microbial origins, indicating a possible role of bacterial metabolism in APE progression. The results show promise for detecting an oncoming APE using EBC metabolites, thus permitting early intervention to abort such an event.


Assuntos
Fibrose Cística , Adulto , Biomarcadores , Testes Respiratórios , Criança , Fibrose Cística/diagnóstico , Humanos , Espectrometria de Massas , Metabolômica , Projetos Piloto
8.
Adv Exp Med Biol ; 1207: 237-264, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32671753

RESUMO

Autophagy is an evolutionarily conserved process in eukaryotes that processes the turnover of intracellular substances. Atherosclerosis is a disease caused by multiple factors, it mainly occurs on the walls of large and medium blood vessels and atherosclerotic plaques form in the intima of the blood vessels. Hyperlipidemia is considered to be a very dangerous factor leading to cardiovascular and cerebrovascular diseases, especially atherosclerosis. This chapter mainly introduces the key role of autophagy in hyperlipidemia and atherosclerosis, that is, impaired lipophagy affects the degradation of triacylglycerol, cholesterol, etc., leading to hyperlipidemia in atherosclerosis. In patients, excessive levels of autophagy accelerate the rupture of atherosclerotic plaque. This chapter also describes the advances in the treatment of atherosclerosis and hyperlipidemia by targeted autophagy.


Assuntos
Aterosclerose , Autofagia , Hiperlipidemias , Colesterol , Humanos , Placa Aterosclerótica , Triglicerídeos
9.
Trends Analyt Chem ; 118: 158-169, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32831436

RESUMO

Mass spectrometry (MS) plays an important role in seeking biomarkers for disease detection. High-quality quantitative data is needed for accurate analysis of metabolic perturbations in patients. This article describes recent developments in MS-based non-targeted metabolomics research with applications to the detection of several major common human diseases, focusing on study cohorts, MS platforms utilized, statistical analyses and discriminant metabolite identification. Potential disease biomarkers recently discovered for type 2 diabetes, cardiovascular disease, hepatocellular carcinoma, breast cancer and prostate cancer through metabolomics are summarized, and limitations are discussed.

10.
Anal Chem ; 90(22): 13767-13774, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30379062

RESUMO

Flow injection-traveling-wave ion mobility-mass spectrometry (FI-TWIM-MS) was applied to the nontargeted metabolic profiling of serum extracts from 61 prostate-cancer (PCa) patients and 42 controls with an analysis speed of 6 min per sample, including a 3 min wash run. Comprehensive data mining of the mobility-mass domain was used to discriminate species with various charge states and filter matrix salt-cluster ions. Specific criteria were developed to ensure correct grouping of adducts, in-source fragments, and impurities in the data set. Endogenous metabolites were identified with high confidence using FI-TWIM-MS/MS and collision-cross-section (CCS) matching with chemical standards or CCS databases. PCa patient samples were distinguished from control samples with good accuracies (88.3-89.3%), sensitivities (88.5-90.2%), and specificity (88.1%) using supervised multivariate classification methods. Although largely underutilized in metabolomics studies, FI-TWIM-MS proved advantageous in terms of analysis speed, separation of ions in complex mixtures, improved signal-to-noise ratio, and reduction of spectral congestion. Results from this study showcase the potential of FI-TWIM-MS as a high-throughput metabolic-profiling tool for large-scale metabolomics studies.


Assuntos
Análise de Injeção de Fluxo/métodos , Espectrometria de Mobilidade Iônica/métodos , Metabolômica , Neoplasias da Próstata/metabolismo , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade
11.
J Proteome Res ; 16(2): 550-558, 2017 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-28152602

RESUMO

Progressive lung function decline and, ultimately, respiratory failure are the most common cause of death in patients with cystic fibrosis (CF). This decline is punctuated by acute pulmonary exacerbations (APEs), and in many cases, there is a failure to return to baseline lung function. Ultraperformance liquid chromatography quadrupole-time-of-flight mass spectrometry was used to profile metabolites in exhaled breath condensate (EBC) samples from 17 clinically stable CF patients, 9 CF patients with an APE severe enough to require hospitalization (termed APE), 5 CF patients during recovery from a severe APE (termed post-APE), and 4 CF patients who were clinically stable at the time of collection but in the subsequent 1-3 months developed a severe APE (termed pre-APE). A panel containing two metabolic discriminant features, 4-hydroxycyclohexylcarboxylic acid and pyroglutamic acid, differentiated the APE samples from the stable CF samples with 84.6% accuracy. Pre-APE samples were distinguished from stable CF samples by lactic acid and pyroglutamic acid with 90.5% accuracy and in general matched the APE signature when projected onto the APE vs stable CF model. Post-APE samples were on average more similar to stable CF samples in terms of their metabolomic signature. These results show the feasibility of detecting and predicting an oncoming APE or monitoring APE treatment using EBC metabolites.


Assuntos
Cicloexanos/metabolismo , Fibrose Cística/diagnóstico , Fibrose Cística/metabolismo , Ácido Láctico/metabolismo , Metabolômica/métodos , Ácido Pirrolidonocarboxílico/metabolismo , Adolescente , Adulto , Biomarcadores/metabolismo , Testes Respiratórios , Cromatografia Líquida , Fibrose Cística/fisiopatologia , Diagnóstico Precoce , Expiração , Feminino , Humanos , Masculino , Espectrometria de Massas , Projetos Piloto , Índice de Gravidade de Doença
12.
J Am Chem Soc ; 138(47): 15434-15442, 2016 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-27809520

RESUMO

In cancer plasmonic photothermal therapy (PPTT), plasmonic nanoparticles are used to convert light into localized heat, leading to cancer cell death. Among plasmonic nanoparticles, gold nanorods (AuNRs) with specific dimensions enabling them to absorb near-infrared laser light have been widely used. The detailed mechanism of PPTT therapy, however, still remains poorly understood. Typically, surface-enhanced Raman spectroscopy (SERS) has been used to detect time-dependent changes in the intensity of the vibration frequencies of molecules that appear or disappear during different cellular processes. A complete proven assignment of the molecular identity of these vibrations and their biological importance has not yet been accomplished. Mass spectrometry (MS) is a powerful technique that is able to accurately identify molecules in chemical mixtures by observing their m/z values and fragmentation patterns. Here, we complemented the study of changes in SERS spectra with MS-based metabolomics and proteomics to identify the chemical species responsible for the observed changes in SERS band intensities during PPTT. We observed an increase in intensity of the bands at around 1000, 1207, and 1580 cm-1, which were assigned in the literature to phenylalanine, albeit with dispute. Our metabolomics results showed increased levels of phenylalanine, its derivatives, and phenylalanine-containing peptides, providing evidence for more confidence in the SERS peak assignments. To better understand the mechanism of phenylalanine increase upon PPTT, we combined metabolomics and proteomics results through network analysis, which proved that phenylalanine metabolism was perturbed. Furthermore, several apoptosis pathways were activated via key proteins (e.g., HADHA and ACAT1), consistent with the proposed role of altered phenylalanine metabolism in inducing apoptosis. Our study shows that the integration of the SERS with MS-based metabolomics and proteomics can assist the assignment of signals in SERS spectra and further characterize the related molecular mechanisms of the cellular processes involved in PPTT.


Assuntos
Ouro/farmacologia , Metabolômica , Nanotubos/química , Neoplasias/patologia , Fenilalanina/metabolismo , Fototerapia , Proteômica , Análise Espectral Raman , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ouro/química , Humanos , Tamanho da Partícula , Propriedades de Superfície , Fatores de Tempo
13.
J Proteome Res ; 13(7): 3444-54, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24922590

RESUMO

Prostate cancer (PCa) is the second leading cause of cancer-related mortality in men. The prevalent diagnosis method is based on the serum prostate-specific antigen (PSA) screening test, which suffers from low specificity, overdiagnosis, and overtreatment. In this work, untargeted metabolomic profiling of age-matched serum samples from prostate cancer patients and healthy individuals was performed using ultraperformance liquid chromatography coupled to high-resolution tandem mass spectrometry (UPLC-MS/MS) and machine learning methods. A metabolite-based in vitro diagnostic multivariate index assay (IVDMIA) was developed to predict the presence of PCa in serum samples with high classification sensitivity, specificity, and accuracy. A panel of 40 metabolic spectral features was found to be differential with 92.1% sensitivity, 94.3% specificity, and 93.0% accuracy. The performance of the IVDMIA was higher than the prevalent PSA test. Within the discriminant panel, 31 metabolites were identified by MS and MS/MS, with 10 further confirmed chromatographically by standards. Numerous discriminant metabolites were mapped in the steroid hormone biosynthesis pathway. The identification of fatty acids, amino acids, lysophospholipids, and bile acids provided further insights into the metabolic alterations associated with the disease. With additional work, the results presented here show great potential toward implementation in clinical settings.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Próstata/diagnóstico , Idoso , Biomarcadores Tumorais/isolamento & purificação , Estudos de Casos e Controles , Cromatografia Líquida de Alta Pressão , Estudos de Viabilidade , Humanos , Masculino , Metabolômica , Pessoa de Meia-Idade , Neoplasias da Próstata/sangue , Espectrometria de Massas em Tandem
14.
Biomed Pharmacother ; 170: 115991, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38086149

RESUMO

Iron deficiency anemia (IDA) is the most common nutrient-related health problem in the world. There is still a lack of comprehensive comparative study on the efficacies of commonly used iron supplements such as polysaccharide iron complex (PIC), iron protein succinylate (IPS) and ferrous succinate (FS) for IDA. In this study, we compared the PIC, IPS and FS efficacies in IDA rats via intragastric administration. The results showed that the three iron supplements had similar efficacies. PIC/IPS/FS at a dose of 15 mg Fe/kg/d for 10 d increased the hematological and serum biochemical parameters to 2.15/2.12/2.18 (Hb), 1.71/1.67/1.69 (RBC), 2.10/2.11/2.12 (HCT), 1.26/1.22/1.22 (MCV), all 1.34 (MCH), 1.15/1.15/1.14 (MCHC), 1.94/1.82/1.91 (SF), 9.75/9.67/9.53 (SI), and 23.30/22.68/21.64 (TS) times, and reduced TIBC to 0.42/0.43/0.44 times, compared to untreated IDA rats. PIC performed slightly better than IPS and FS in restoring MCV level. Meanwhile, the heart, spleen and kidney coefficients reduced to 67%/74%/65% (heart), all 59% (spleen) and 87%/88%/88% (kidney), and the liver coefficient increased to 116%/115%/116%, compared to untreated IDA rats. The liver iron content was found to be more affected by IDA than the spleen iron content. PIC/IPS/FS at 15 mg Fe/kg/d increased organ iron contents to 4.20/3.97/4.03 times (liver) and 1.36/1.24/1.41 times (spleen) within 10 d compared to untreated IDA rats, and PIC-H and FS were slightly better than IPS in restoring spleen iron content. The results of this study can provide useful data information for the comparison of three iron supplements, PIC, IPS and FS.


Assuntos
Anemia Ferropriva , Ratos , Animais , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/metabolismo , Ferro/metabolismo , Polissacarídeos/uso terapêutico
15.
Int J Biol Macromol ; 230: 123266, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36646351

RESUMO

The discovery of new anti-cancer drugs targeting the PD-1/PD-L1 pathway has been a research hotspot in recent years. In this study, biological affinity ultrafiltration (BAU), UPLC-HRMS, molecular dynamic (MD) simulations and molecular docking methods were applied to search for endogenous active compounds that can inhibit the binding of PD-L1 to PD-1. We screened dozens of potential cancer related endogenous compounds. Surprisingly, cyclic adenosine monophosphate (cAMP) was found to have a direct inhibitory effect on the PD-1/PD-L1 binding with an in vitro IC50 value of about 36.4 ± 9.3 µM determined by homogeneous time-resolved fluorescence (HTRF) assay. cAMP could recover the proliferation of Jurkat T cells co-cultured with DU-145 cells and may suppress PD-L1 expression of DU-145 cells. cAMP was demonstrated to bind and induce PD-L1 dimerization by FRET assay, and also predicted by MD simulations and molecular docking. The finding of cAMP as a potential inhibitor directly targeting the PD-1/PD-L1 interaction could advance our understanding of the activity of endogenous compounds regulating PD-L1.


Assuntos
Antígeno B7-H1 , Receptor de Morte Celular Programada 1 , Humanos , Antígeno B7-H1/metabolismo , Células Jurkat , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Receptor de Morte Celular Programada 1/metabolismo , AMP Cíclico/metabolismo
16.
J Hazard Mater ; 454: 131572, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37148790

RESUMO

Biodegradable plastics have emerged as a potential solution to the mounting plastic pollution crisis. However, current methods for evaluating the degradation of these plastics are limited in detecting structural changes rapidly and accurately, particularly for PBAT, which contains worrying benzene rings. Inspired by the fact that the aggregation of conjugated groups can endow polymers with intrinsic fluorescence, this work found that PBAT emits a bright blue-green fluoresces under UV irradiation. More importantly, we pioneered a degradation evaluation approach to track the degradation process of PBAT via fluorescence. A blue shift of fluorescence wavelength as the thickness and molecular weight of PBAT film decreased during degradation in an alkali solution was observed. Additionally, the fluorescence intensity of the degradation solution increased gradually as the degradation progressed, and was found to be exponentially correlated with the concentration of benzene ring-containing degradation products following filtration with the correlation coefficient is up to 0.999. This study proposes a promising new strategy for monitoring the degradation process with visualization and high sensitivity.

17.
ACS Appl Mater Interfaces ; 12(8): 9347-9354, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31994863

RESUMO

Aqueous zinc-ion batteries (AZIBs) are one of the promising choices for the future large-scale grid energy storage, in which Mn-based cathode materials have the advantages of low cost and environmental friendliness. However, their capacity delivery and cycling stability are limited by the large bulk-induced incomplete zincation and structure pulverization. Here, we develop a strategy of epitaxial polymerization in the liquid phase to fabricate two-dimensional (2D) MnOx/polypyrrole nanosheets to enhance the zinc-ion storage by realizing the efficient utilization of active materials and improving the structural stability via a polymerized framework. An ultrahigh capacity of 408 mAh g-1 is demonstrated at 1C rate, and an excellent capacity retention of 78% is realized after 2800 cycles at 5C rate for the AZIB. Electrochemical and morphological characterizations reveal that the unique 2D structure contributes to both the electron/ion conductivity and structural stability. The epitaxial polymerization of the conducting polymer in the liquid phase provides a new perspective to the synthesis of high-performance electrode materials and 2D conducting polymers.

18.
Nanoscale ; 11(24): 11730-11735, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31180401

RESUMO

Thermal dissipation and thermal insulation are important for maintaining the normal operation of devices, extending the service life of instruments, ensuring efficient energy utilization, and improving temperature-related human comfort. Yet it is difficult to achieve both the functions of thermal dissipation and thermal insulation in a single material with a specific thermal conductivity under specific conditions. In this work, based on the huge difference in thermal conductivity between air and reduced graphene oxide (rGO), a pressure-induced mechanism is used to regulate the amount of air inside an rGO foam, so that a periodic reversible change of thermal conductivity can be realized, achieving the dual functions of thermal dissipation and thermal insulation to meet the requirements of different application scenarios. Further fitting calculations suggest that the thermal conductivity of rGO foam is positively and negatively associated with the applied pressure and temperature, respectively, and it can be calculated for given pressure and temperature conditions. The pressure-induced reversible regulation of thermal conductivity in rGO foam provides a new design construct for smart thermal-management devices, and a new direction of application for 2D materials.

19.
Clin Chim Acta ; 481: 121-125, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29510122

RESUMO

BACKGROUND: High level of red blood cell distribution width (RDW) has been associated with adverse outcomes in coronary artery disease patients. We aimed to investigate the relationship between RDW and the risk of myocardial injury in chest pain patients. METHODS AND RESULTS: We retrospectively reviewed 2078 chest pain patients with suspected acute myocardial infarction. Myocardial injury was defined as high-sensitivity cardiac troponin T (hs-cTnT) >14 ng/L. RDW was associated with hs-cTnT (r = 0.607) and the risk of myocardial injury stepwise increased across increasing RDW quartiles in all subgroups based on age and sex. The receiver operating characteristic curve analysis was calculated to assess the elevated RDW to predict myocardial injury, with the cutoff value of 13.25%. RDW had a high sensitivity (78.10%), specificity (87.44%), as well as positive predictive value (77.48%). The area under the curve (AUC) for all patients was 0.88 (95%CI 0.87, 0.90) and there is no statistical significant in AUCs for all subgroups. CONCLUSIONS: Elevated RDW was significantly associated with a higher risk of myocardial injury in chest pain patients with potential acute myocardial infarction. The RDW may be helpful to identify myocardial injury in such patients.


Assuntos
Dor no Peito/patologia , Índices de Eritrócitos , Eritrócitos/patologia , Infarto do Miocárdio/patologia , Miocárdio/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Células Sanguíneas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Troponina T/análise , Adulto Jovem
20.
Nanoscale ; 10(3): 958-963, 2018 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-29143051

RESUMO

Sodium-ion battery (SIB) technology is competitive in the fields of transportation and grid storage, which require electrode materials showing rapid energy conversion (high rate capability) and long cycle life. In this work, a NaTi2(PO4)3/C (NTP/C) nanocomposite with an open holey-structured framework was successfully prepared for the first time using a solvothermal reaction followed by pyrolysis. The nanocomposite realized fast sodium-ion transport and thus preferable battery performances. Within the wide rate range of 0.5-50C, only a very small decrease in capacity from 124 to 120 mA h g-1 was observed. A high discharge capacity of 103 mA h g-1 (88.3% retention of the 1st cycle) was delivered even after 10 000 cycles at an ultrahigh rate of 50C without any obvious morphological change and without structural pulverization. Forming open channels for ion transport proved to contribute to such performance enhancement and therefore has the potential to become a universal model for the development of sustainable electrode materials in SIBs and other battery systems.

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