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1.
Anal Chem ; 96(31): 12817-12826, 2024 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-39052489

RESUMO

Single-cell analysis by mass spectrometry (MS) is emerging as a powerful tool that not only contributes to cellular heterogeneity but also offers an unprecedented opportunity to predict pathology onset and facilitates novel biomarker discovery. However, the development of single-cell MS analysis techniques with a focus on sample extraction, separation, and ionization methods for volume-limited samples and complexity of cellular samples are still a big challenge. In this study, we present a high-throughput approach to inkjet drop on demand printing single-cell MS for rapid screening of biomarkers of polycyclic aromatic hydrocarbon (PAH) exposure at the KYSE-150 cell, aiming to elucidate the pathogenesis of PAH-induced esophageal cancer. With an analytical bulk KYSE-150 cell throughput of up to 51 cells per minute, the method provides a new opportunity for simultaneous single-cell analysis of multiple biomarkers. We screened 930 characteristic ions from 3,683 detected peak signals and identified 91 distinctive molecules that exhibited significant differences under various concentrations of PAH exposure. These molecules have potential as clinical diagnostic biomarkers. Additionally, the current study identifies specific biomarkers that behave completely opposite in single-cell and multicell lipidomics as the concentration of PAH changes. These biomarkers potentially subdivide KYSE-150 cells into PAH-sensitive and PAH-insensitive types, providing a basis for revealing PAH toxicity and disease pathogenesis from the heterogeneity of cellular metabolism.


Assuntos
Espectrometria de Massas , Hidrocarbonetos Policíclicos Aromáticos , Análise de Célula Única , Hidrocarbonetos Policíclicos Aromáticos/análise , Humanos , Biomarcadores/metabolismo , Biomarcadores/análise , Linhagem Celular Tumoral , Impressão , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/análise
2.
Anal Chem ; 96(21): 8484-8491, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38753368

RESUMO

It is challenging to prepare a highly selective mass spectrometry (MS) ion source for the rapid and highly sensitive detection of analytes, especially mycotoxins. In this study, an amino and tetrazine bifunctionalized multiarm PEG derivative (NH2HCl-4armPEG10K-(MTz)3), which can be easily immobilized on the substrate by the addition reaction between amino and polydopamine, was used for the preparation of MS ionization substrate. NH2HCl-4armPEG10K-(MTz)3 can also be used as a linker to immobilize sufficient streptavidin (SA) on the surface of the substrate by a click reaction. The process further promotes the immobilization of broad-spectrum antibodies (3D4), which were used as the recognition element for ZEN and its metabolites. The prepared SSS-Au-PDA-4armPEG10K-SA-3D4 not only can rapidly enrich ZEN and its metabolites with high selectivity but also shows good antifouling properties in the matrix. After simple sample preparation, the prepared SSS-Au-PDA-4armPEG10K-SA-3D4 can be directly coupled with MS to achieve high sensitivity (LODs: 0.18-0.66 ng/mL, LOQs: 0.5-1.0 ng/mL) and selective detection of ZEN and its metabolites in the matrix. At the same time, satisfactory recoveries (83.60-97.80%) and precision (RSD: 2.80-9.10%) can also be obtained. The prepared SSS-Au-PDA-4armPEG10K-SA-3D4 is expected to provide a powerful tool for the rapid and highly sensitive determination of multiple targets by MS.


Assuntos
Polietilenoglicóis , Polietilenoglicóis/química , Espectrometria de Massas , Animais , Incrustação Biológica/prevenção & controle , Limite de Detecção
3.
Anal Chem ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39178331

RESUMO

The development of a highly specific recognition electrospray ionization source presents a major challenge for achieving rapid ambient mass spectrometry (AMS) detection of trace harmful substances in complex samples. In this study, we constructed a molecular imprinting nanofiber electrospinning membrane-coated steel substrate (MINMCS) based on the electrospinning strategy. This was designed as a highly specific recognition and enrichment electrospray ionization source module for AMS, where the molecular imprinting nanofiber membrane served as an excellent extraction and enrichment layer. The prepared ionization source demonstrated a sufficient loading capacity for three bioamines (BAs): histamine (HIS), tyramine (TYR), and tryptamine (TRY). With simplified sample pretreatment, this ionization source exhibited sensitivity comparable to that of high performance liquid chromatography-mass spectrometry (HPLC-MS/MS). Moreover, the entire analysis process could be completed within 1 min with acceptable recoveries (83.21-101.80%). In brief, this study introduces a new integrated recognition and enrichment electrospray ionization source for the detection of harmful substances such as bioamines, showcasing significant commercial potential for the rapid detection of foodborne harmful compounds.

4.
BMC Plant Biol ; 24(1): 652, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982365

RESUMO

BACKGROUND: Protein phosphatase class 2 C (PP2C) is the largest protein phosphatase family in plants. Members of the PP2C gene family are involved in a variety of physiological pathways in plants, including the abscisic acid signalling pathway, the regulation of plant growth and development, etc., and are capable of responding to a wide range of biotic and abiotic stresses, and play an important role in plant growth, development, and response to stress. Apocynum is a perennial persistent herb, divided into Apocynum venetum and Apocynum hendersonii. It mainly grows in saline soil, deserts and other harsh environments, and is widely used in saline soil improvement, ecological restoration, textiles and medicine. A. hendersonii was found to be more tolerant to adverse conditions. The main purpose of this study was to investigate the PP2C gene family and its expression pattern under salt stress and to identify important candidate genes related to salt tolerance. RESULTS: In this study, 68 AvPP2C genes and 68 AhPP2C genes were identified from the genomes of A. venetum and A. hendersonii, respectively. They were classified into 13 subgroups based on their phylogenetic relationships and were further analyzed for their subcellular locations, gene structures, conserved structural domains, and cis-acting elements. The results of qRT-PCR analyses of seven AvPP2C genes and seven AhPP2C genes proved that they differed significantly in gene expression under salt stress. It has been observed that the PP2C genes in A. venetum and A. hendersonii exhibit different expression patterns. Specifically, AvPP2C2, 6, 24, 27, 41 and AhPP2C2, 6, 24, 27, 42 have shown significant differences in expression under salt stress. This indicates that these genes may play a crucial role in the salt tolerance mechanism of A. venetum and A. hendersonii. CONCLUSIONS: In this study, we conducted a genome-wide analysis of the AvPP2C and AhPP2C gene families in Apocynum, which provided a reference for further understanding the functional characteristics of these genes.


Assuntos
Apocynum , Filogenia , Apocynum/genética , Regulação da Expressão Gênica de Plantas , Família Multigênica , Proteína Fosfatase 2C/genética , Proteína Fosfatase 2C/metabolismo , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Tolerância ao Sal/genética , Genes de Plantas , Perfilação da Expressão Gênica
5.
Anal Chem ; 95(29): 10984-10991, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37449836

RESUMO

Ambient mass spectrometry (AMS) allows direct analysis of various raw food samples with minimal or no sample pretreatment, but the trace analytes in complex food samples still have problems with limitations. In this work, we developed a platform based on coated stainless steel sheet spray mass spectrometry for fast, in situ, high-throughput, and high selectivity multiresidue analysis of fluoroquinolone drugs (FQs). The sensitivity of the platform was enhanced via coupling broad-spectrum antibodies against FQs to graphene oxide coated blade spray (CBS)-MS through a streptavidin-biotin (SA-biotin) interaction. The prepared platform had sufficient loading capacity for SA (1.37 mg/piece) and the antibody (84.8 µg/piece), which is greater than that of physical mixing and the EDC/NHS covalent coupling strategy. With simplified sample pretreatment, this platform demonstrated comparable sensitivity to high performance liquid chromatography-mass spectrometry (HPLC-MS/MS) (0.08-0.16 ng/mL in phosphate-buffered saline and 0.21-0.32 ng/mL in diluted milk). Meanwhile, compared with HPLC-MS/MS, the method is rapid (enrichment: 10 min, detection: <1 min) and acceptable recoveries (81.94-102.08%) can be obtained. The presence of analytes can be monitored by MS/MS spectra, and multiple analytes can be measured simultaneously in a single assay. This study is expected to provide a powerful and portable tool for rapid laboratory analysis and reliable screening in the field.


Assuntos
Biotina , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Fluoroquinolonas , Anticorpos
6.
Rapid Commun Mass Spectrom ; 37(5): e9428, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36346288

RESUMO

Antibiotics have important medical value, but they need to be monitored when used as veterinary drugs. We report α-cyano-4-hydroxycinnamic acid/p-phenylenediamine (CHCA/PPD) hybrid as a novel matrix for enhanced matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) in situ the spatial distribution of antibiotic drugs in grass carp tissues. METHOD: We have used MALDI-TOF-MSI in positive ion mode for the analysis of quinolones and sulfonamides in grass carps. A novel CHCA/PPD matrix was prepared and applied using a simple method to improve the analysis. RESULTS: Compared with the traditional matrix, CHCA/PPD significantly improved the detection intensity of quinolones and sulfonamides with better sensitivity (17.20%-94.30%) and reproducibility. For demonstration, this novel matrix was successfully applied to visualize enrofloxacin (ENR) in grass carp tissues, with the entire abundance differences clearly observed based on MALDI-MSI. The concentration levels in different tissues were determined, with a calibration curve of 10-2000 µg/ml (R2 > 0.993). CONCLUSION: This study was the first to introduce CHCA/PPD as a novel matrix, and the classical acid-base mixing was used to improve the ionization effect of the traditional matrix CHCA in MALDI. Based on CHCA/PPD, MALDI-MSI detected ENR in different grass carp tissues for the first time and realized the spatial distribution and concentration detection.


Assuntos
Antibacterianos , Sulfonamidas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Reprodutibilidade dos Testes , Ácidos Cumáricos/química , Lasers
7.
Nano Lett ; 22(19): 7853-7859, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36126113

RESUMO

The capacity to regulate the signaling amplitude of membrane receptors in a user-defined manner would open various opportunities for precise biological study and therapy. While partial agonists enabled downtuning of cellular responses, they required esoteric optimization of the ligand-receptor interface, limiting their practical applications. Herein, we developed an aptamer-functionalized, tweezer-like nanodevice to dynamically modulate the cellular behavior through control over the distance between receptors in the dimer with no need to involve complicated structural analysis. By combining a reversible conformation switch with aptamer-based molecular recognition, this nanodevice showed excellent performance on dynamic regulation of CD28 receptor-mediated T cell immunity. With the modular design, this nanodevice could be extended to dynamically modulate the activity of other membrane receptors (e.g., c-Met), expecting to offer a new paradigm for precise study and manipulation of specific molecular events in complex biological systems.


Assuntos
Aptâmeros de Nucleotídeos , DNA , Aptâmeros de Nucleotídeos/química , Antígenos CD28 , DNA/química , Ligantes , Oligonucleotídeos , Transdução de Sinais
8.
Nano Lett ; 22(23): 9441-9449, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36442508

RESUMO

Approaches to DNA probe-mediated precision medicine have been extensively explored for the diagnosis and treatment of diverse types of cancer. Despite this, simple nanoscale devices with the required recognition specificity and sensitivity for clinical application have remained elusive until now. Here, we report a pH-driven covalent nanoscale device that integrates pH-responsive, switchable structure and proximity-driven covalent cross-linking. A tumor acidic, pH-driven mechanism eliminates "on-target, off-tumor" nonspecific recognition. By manipulating covalent binding to target molecule on the cell surface, this nanodevice avoids binding-then-shedding to improve the sensitivity of tumor recognition. We envision that this pH-driven covalent nanoscale device will inspire more clinical applications toward specific, long-term tumor imaging in the cancer microenvironment.


Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Microambiente Tumoral , Diagnóstico por Imagem , Concentração de Íons de Hidrogênio
9.
Int J Mol Sci ; 24(5)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36902010

RESUMO

Centrifugal projections in the olfactory system are critical to both olfactory processing and behavior. The olfactory bulb (OB), the first relay station in odor processing, receives a substantial number of centrifugal inputs from the central brain regions. However, the anatomical organization of these centrifugal connections has not been fully elucidated, especially for the excitatory projection neurons of the OB, the mitral/tufted cells (M/TCs). Using rabies virus-mediated retrograde monosynaptic tracing in Thy1-Cre mice, we identified that the three most prominent inputs of the M/TCs came from the anterior olfactory nucleus (AON), the piriform cortex (PC), and the basal forebrain (BF), similar to the granule cells (GCs), the most abundant population of inhibitory interneurons in the OB. However, M/TCs received proportionally less input from the primary olfactory cortical areas, including the AON and PC, but more input from the BF and contralateral brain regions than GCs. Unlike organizationally distinct inputs from the primary olfactory cortical areas to these two types of OB neurons, inputs from the BF were organized similarly. Furthermore, individual BF cholinergic neurons innervated multiple layers of the OB, forming synapses on both M/TCs and GCs. Taken together, our results indicate that the centrifugal projections to different types of OB neurons may provide complementary and coordinated strategies in olfactory processing and behavior.


Assuntos
Prosencéfalo Basal , Córtex Olfatório , Camundongos , Animais , Bulbo Olfatório/fisiologia , Condutos Olfatórios , Olfato/fisiologia
10.
Molecules ; 28(4)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36838655

RESUMO

Agarwood, a highly valuable resin/wood combination with diverse pharmacological activities but scarce supply, has a long history of being used as a medicine in several medical systems. Grafted Kynam agarwood (GKA) has been cultivated successfully recently and has the qualities meeting the definition of premium Kynam agarwood. However, there are few comprehensive comparisons between GKA and normal agarwood in terms of traits, global composition, and activity, and some key issues for GKA to be adopted into the traditional Chinese medical (TCM) system have not been elaborated. The two types of agarwood samples were evaluated in terms of trait characteristics, physicochemical indicators, key component groups, and global compositional profile. Furthermore, a molecular docking was performed to investigate the active ingredients. In vitro activity assays were performed to evaluate the activation of adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) by GKA and normal agarwood. The results revealed that, overall, the traits, microscopic characteristics, chemical composition types, and bioactivity between GKA and normal agarwood were similar. The main differences were the content of resin (ethanolic extract content), the content of key component groups, and the composition of the different parent structural groups of 2-(2-phenethyl) chromones (PECs). The contents of total PEC and ethanol extract content of GKA were significantly higher than those of normal agarwood. The MS-based high-throughput analysis revealed that GKA has higher concentrations of sesquiterpenes and flindersia-type 2-(2-phenylethyl) chromones (FTPECs) (m/z 250-312) than normal agarwood. Molecular docking revealed that parent structural groups of FTPECs activated multiple signaling pathways, including the AMPK pathway, suggesting that FTPECs are major active components in GKA. The aim of this paper is to describe the intrinsic reasons for GKA as a high-quality agarwood and a potential source for novel drug development. We combined high-throughput mass spectrometry and multivariate statistical analysis to infer the different components of the two types of agarwood. Then we combined virtual screening and in vitro activity to construct a component/pharmacodynamic relationship to explore the causes of the activity differences between agarwood with different levels of quality and to identify potentially valuable lead compounds. This strategy can also be used for the comprehensive study of other TCMs with different qualities.


Assuntos
Proteínas Quinases Ativadas por AMP , Thymelaeaceae , Simulação de Acoplamento Molecular , Thymelaeaceae/química , Cromonas/química , Madeira/química , Resinas Vegetais/análise , Extratos Vegetais/química , Flavonoides/química
11.
Angew Chem Int Ed Engl ; 62(39): e202307656, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37423897

RESUMO

Nongenetic strategies that enable control over the cell-cell interaction network would be highly desired, particularly in T cell-based cancer immunotherapy. In this work, we developed an aptamer-functionalized DNA circuit to modulate the interaction between T cells and cancer cells. This DNA circuit was composed of recognition-then-triggering and aggregation-then-activation modules. Upon recognizing target cancer cells, the triggering strand was released to induce aggregation of immune receptors on the T cell surface, leading to an enhancement of T cell activity for effective cancer eradication. Our results demonstrated the feasibility of this DNA circuit for promoting target cancer cell-directed stimulation of T cells, which, consequently, enhanced their killing effect on cancer cells. This DNA circuit, as a modular strategy to modulate intercellular interactions, could lead to a new paradigm for the development of nongenetic T cell-based immunotherapy.


Assuntos
Aptâmeros de Nucleotídeos , Neoplasias , Linfócitos T/metabolismo , Aptâmeros de Nucleotídeos/metabolismo , DNA/metabolismo , Membrana Celular/metabolismo , Imunoterapia , Neoplasias/terapia , Neoplasias/metabolismo
12.
Angew Chem Int Ed Engl ; 62(39): e202306691, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37455257

RESUMO

Life-like hierarchical architecture shows great potential for advancing intelligent biosensing, but modular expansion of its sensitivity and functionality remains a challenge. Drawing inspiration from intracellular liquid-liquid phase separation, we discovered that a DNA-encoded artificial cell with a liquid core (LAC) can enhance peroxidase-like activity of Hemin and its DNA G-quadruplex aptamer complex (DGAH) without substrate-selectivity, unlike its gelled core (GAC) counterpart. The LAC is easily engineered as an ultrasensitive biosensing system, benefiting from DNA's high programmability and unique signal amplification capability mediated by liquid-liquid phase separation. As proof of concept, its versatility was successfully demonstrated by coupling with two molecular recognition elements to monitor tumor-related microRNA and profile cancer cell phenotypes. This scalable design philosophy offers new insights into the design of next generation of artificial cells-based biosensors.


Assuntos
Aptâmeros de Nucleotídeos , Células Artificiais , Técnicas Biossensoriais , DNA Catalítico , Quadruplex G , MicroRNAs , Neoplasias , Humanos , DNA/genética , Hemina , DNA Catalítico/metabolismo
13.
Anal Chem ; 94(18): 6719-6727, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35475631

RESUMO

Discovering the fungus-infected or mycotoxin-contaminated biomarkers is significant for systems biology since the metabolites in biological samples have significant polarity differences in both stochastic gene expression and microenvironmental change. Here, we aim to establish a comprehensive method for a lipidome by ion mobility mass spectrometry (IMS) merged with chemometrics to accurately find out the more scientific markers of cell interference by mycotoxins and for pathogenesis exploration and drug development. The differences in the abundances of several small molecules found in these metabolites were explored through multivariate statistical analysis, including principal component analysis (PCA) and orthogonal partial least-squares discriminant analysis (OPLS-DA), to further screen biomarkers. Good applicability and predictability were demonstrated by R2(X) and Q2 (R2 = 0.959, Q2 = 0.999). Five compounds with m/z values of 512.502 8, 540.5343, 722.525 8, 787.667 5, and 813.683 0 were selected as markers, and four of them were further confirmed by chemical standards (i.e., MSMS of m/z 813.683 0 covering m/z 86.0978, 125.0008, 184.0745, and 185.0781). In summary, we demonstrated the integration of UPLC-TOF-IMS and the chemometrics approach to elucidate identified biomarkers, which also provides a new way of thinking for covering lipid biomarkers or prognostic indicators for mycotoxins.


Assuntos
Lipidômica , Micotoxinas , Biomarcadores , Cromatografia Líquida de Alta Pressão/métodos , Células Hep G2 , Humanos , Metabolômica/métodos
14.
Electrophoresis ; 43(18-19): 1841-1849, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35562841

RESUMO

Sorghum is an important grain with a high economic value for liquor production. Tracing the geographical origin of sorghum is vital to guarantee the liquor flavor. Soldering iron-based rapid evaporative ionization mass spectrometry (REIMS) combined with chemometrics was developed for the real-time discrimination of the sorghum's geographical origin. The working conditions of soldering iron-based ionization were optimized, and then the obtained MS profiling data were processed using chemometrics analysis methods, including principal component analysis-linear discriminant analysis and orthogonal projection to latent structures discriminant analysis (OPLS-DA). A recognition model was established, and discriminations of sorghum samples from 10 provinces in China were achieved with a correct rate higher than 90%. On the basis of OPLS-DA, the specific ions of m/z 279.2327, 281.2479, and 283.2639 had relatively strong discrimination power for the geographical origins of sorghum. The developed method was successfully applied in the discrimination of sorghum origins. The results indicated that the soldering iron-based REIMS technique combined with chemometrics is a useful tool for direct, fast, and real-time ionization of poor conductivity samples and acquisition of metabolic profiling data.


Assuntos
Sorghum , Quimiometria , Análise Discriminante , Grão Comestível , Ferro , Espectrometria de Massas/métodos
15.
Molecules ; 27(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36144578

RESUMO

Lycium barbarum L. (LB) fruits have high nutritive values and therapeutic effects. The aim of this study was to comprehensively evaluate the differences in phenolic composition of LB fruits from different geographical regions. Different methods of characterization and statistical analysis of data showed that different geographic sources of China could be significantly separated from each other. The highest total phenolic compound (TPC) content was observed in LB fruits from Ningxia (LBN), followed by those from Gansu (LBG) and Qinghai (LBQ). The Fourier transform infrared (FTIR) spectra of LB fruits revealed that LBQ had a peak at 2972 cm-1 whereas there was no similar peak in LBG and LBQ. A new HPLC method was established for the simultaneous determination of 8 phenolic compounds by quantitative analysis of multiple components by a single marker (QAMS), including 4 phenolic acids (chlorogenic acid, caffeic acid, 4-hydroxycinnamic acid, and ferulic acid), 1 coumarin (scopoletin), and 3 flavonoids (kaempferol-3-O-rutinoside, rutin, and narcissoside). It was showed that rutin was the most dominant phenolic compound in LBQ, although the average content of 4 phenolic acids was also high in LBQ, and scopoletin was the richest in LBG. UHPLC-Q-TOF-MS was used to qualitatively analyze the phenolics, which showed LBN was abundant in phenolic acids, LBQ was rich in flavonoids, and coumarins were the most plentiful in LBG. In conclusion, this study can provide references for the quality control and evaluation of phenolics in LB fruits and their by-products.


Assuntos
Lycium , Ácidos Cafeicos , Ácido Clorogênico , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Frutas/química , Hidroxibenzoatos , Fenóis/análise , Rutina/análise , Escopoletina/análise
16.
Angew Chem Int Ed Engl ; 61(7): e202111151, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-34873818

RESUMO

Manipulation of cell-cell interactions via cell surface engineering has potential biomedical applications in tissue engineering and cell therapy. However, manipulation of the comprehensive and multiple intercellular interactions remains a challenge and missing elements. Herein, utilizing a DNA triangular prism (TP) and a branched polymer (BP) as functional modules, we fabricate tunable DNA scaffold networks on the cell surface. The responsiveness of cell-cell recognition, aggregation and dissociation could be modulated by aptamer-functionalized DNA scaffold networks with high accuracy and specificity. By regulating the DNA scaffold networks coated on the cell surface, controlled intercellular molecular transportation is achieved. Our tunable network provides a simple and extendible strategy which addresses a current need in cell surface engineering to precisely manipulate cell-cell interactions and shows promise as a general tool for controllable cell behavior.


Assuntos
DNA/química , Redes Neurais de Computação , Polímeros/química , Comunicação Celular , Células HeLa , Células Hep G2 , Humanos
17.
Histopathology ; 78(2): 300-309, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32767784

RESUMO

AIMS: Signet ring cell carcinoma (SRCC) is challenging to recognise on intra-operative frozen sections, with known high false-negative rates. The objective of this study was to investigate common factors contributing to discrepancies between intra-operative frozen diagnoses and those made upon review of permanent sections, and summarise our experiences gained and lessons learned on minimising errors on intra-operative frozen diagnoses of gastrointestinal SRCC. METHODS AND RESULTS: We retrospectively examined our pathology database from 25 May 2000 to 1 January 2018 and re-reviewed intra-operative frozen sections and permanent haematoxylin and eosin (H&E) slides for specimens confirmed with SRCC on permanent sections. This study includes 83 specimens taken from 50 patients, with an accuracy of 85.5%. Main common factors causing discordance or deferral in recognising SRCC between intra-operative frozen procedures and permanent sections include: (i) resemblance of clusters of SRCC cells with a myxoid background; (ii) disguise as normal or reactive cells (histiocytes, macrophages, large reactive lymphocytes, plasma cells or adipocytes) due to their relatively clear or depleted cytoplasmic mucin; and (iii) histological sampling errors, leading to misses of small foci of SRCC on frozen section slides. CONCLUSIONS: An accurate diagnosis of SRCC during intra-operative frozen consultations remains challenging. Based on our experiences and lessons, the most important strategies to reduce diagnostic errors are: (i) understanding the unusual histomorphological features of SRCC cells on frozen sections including, but not limited to, intracellular mucin depletion, absence of desmoplasia and no adjacent pre-cancer changes; and (ii) close attention to abrupt transition from normal architecture (e.g. glandular or submucosal loose connective tissue) to myxoid and/or inflammatory-like appearance, which potentially harbours SRCC.


Assuntos
Carcinoma de Células em Anel de Sinete , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células em Anel de Sinete/diagnóstico , Carcinoma de Células em Anel de Sinete/patologia , Carcinoma de Células em Anel de Sinete/cirurgia , Erros de Diagnóstico , Feminino , Secções Congeladas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Encaminhamento e Consulta , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
18.
Anal Bioanal Chem ; 413(28): 7021-7030, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34642779

RESUMO

Understanding the spatial distribution of bioactive small molecules is indispensable for elucidating their biological or pharmaceutical roles. Here, a rapid and effective analysis strategy was introduced to study the distribution of veterinary drugs in aquatic products. Malachite green (MG), one of the most widely used veterinary drugs in aquaculture, was selected as the targeted compound. Zebrafish (Danio rerio) was used as a model organism. After an exposure test, the matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) technique was applied to directly analyze the content changes of malachite green in zebrafish tissues. The reliable relationship of exposure time and content change of MG was described precisely by the extended Freundlich equation. The process of modeling was discussed in detail, and some important parameters or trend information was obtained, including the maximum content of MG in different fish tissues, time to maximum content, elimination time, equilibrium content, and so on. With a simplification of sample pretreatment, this research strategy can be used for monitoring the spatial distribution of veterinary drugs and related metabolites of laboratory-exposed fish. The obtained model can provide a perspective for rational drug use in aquaculture and precise drug residue detection in production activities.


Assuntos
Corantes de Rosanilina/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Modelos Químicos , Padrões de Referência , Corantes de Rosanilina/normas , Peixe-Zebra
19.
Mikrochim Acta ; 188(8): 246, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34235593

RESUMO

Magnetic covalent organic framework nanocomposite denoted as Fe3O4@TAPB-Tp with core-shell structure was fabricated via a simple template-mediated precipitation polymerization method at mild conditions. The polyimine network shell was created through the polymerization of 1,3,5-tris(4-aminophenyl)-benzene (TAPB) and 1,3,5-triformyl-phloroglucinol (Tp) in tetrahydrofuran (THF) by the Schiff-base reaction. Featuring with large specific surface area (163.19 m2 g-1), good solution dispersibility, and high stability, the obtained Fe3O4@TAPB-Tp exhibited high adsorption capacities and fast adsorption for zearalenone and its derivatives (ZEAs). The adsorption isotherms showed multilayer adsorption dominated at low concentration and monolayer adsorption at high concentration between the interface of ZEAs and Fe3O4@TAPB-Tp. With the Fe3O4@TAPB-Tp as sorbent, a magnetic solid-phase extraction-ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was established for simultaneous adsorption and detection of five ZEAs in complex samples. The proposed method displayed favorable linearity, low limits of detection (0.003 ~ 0.018 µg kg-1), and good repeatability (2.37~10.4%). The developed method has been applied for real sample analysis, with recoveries of 81.27~90.26%. These results showed that Fe3O4@TAPB-Tp has a good application potential for the adsorption of ZEAs in food samples. Magnetic covalent organic framework nanocomposite (Fe3O4@TAPB-Tp) were quickly fabricated at mild conditions and used as effective adsorbent for magnetic solid-phase extraction of zearalenone and its derivatives (ZEAs) from food samples prior to ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis.


Assuntos
Nanopartículas de Magnetita/química , Estruturas Metalorgânicas/química , Micotoxinas/análise , Zearalenona/análise , Adsorção , Animais , Derivados de Benzeno/química , Cromatografia Líquida de Alta Pressão , Ovos/análise , Contaminação de Alimentos/análise , Limite de Detecção , Fenômenos Magnéticos , Leite/química , Micotoxinas/química , Micotoxinas/isolamento & purificação , Nanocompostos/química , Floroglucinol/análogos & derivados , Floroglucinol/química , Polimerização , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem , Zea mays , Zearalenona/análogos & derivados , Zearalenona/isolamento & purificação
20.
Angew Chem Int Ed Engl ; 60(19): 10745-10755, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33555644

RESUMO

DNA-based molecular communications (DMC) are critical for regulating biological networks to maintain stable organismic functions. However, the complicated, time-consuming information transmission process involved in genome-coded DMC and the limited, vulnerable decoding activity generally lead to communication impairment or failure, in response to external stimuli. Herein, we present a conceptually innovative DMC strategy mediated by the DNA framework-based artificial DNA encoder. With the free-radical cascade as a proof-of-concept study, the artificial DNA encoder shows active sensing and real-time actuation, in situ and broad free radical-decoding efficacy, as well as robust resistance to environmental noise. It can also block undesirable short-to-medium-range communications between free radicals and inflammatory networks, leading to a synergistic anti-obesity effect. The artificial DNA encoder-based DMC may be generalized to other communication systems for a variety of applications.


Assuntos
DNA/química , Radicais Livres/química
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