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1.
BMC Plant Biol ; 19(1): 497, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31726984

RESUMO

BACKGROUND: The basic helix-loop-helix (bHLH) transcription factors (TFs), as one of the largest families of TFs, play important roles in the regulation of many secondary metabolites including flavonoids. Their involvement in flavonoids synthesis is well established in vascular plants, but not as yet in the bryophytes. In liverworts, both bisbibenzyls and flavonoids are derived through the phenylpropanoids pathway and share several upstream enzymes. RESULTS: In this study, we cloned and characterized the function of PabHLH1, a bHLH family protein encoded by the liverworts species Plagiochasma appendiculatum. PabHLH1 is phylogenetically related to the IIIf subfamily bHLHs involved in flavonoids biosynthesis. A transient expression experiment showed that PabHLH1 is deposited in the nucleus and cytoplasm, while the yeast one hybrid assay showed that it has transactivational activity. When PabHLH1 was overexpressed in P. appendiculatum thallus, a positive correlation was established between the content of bibenzyls and flavonoids and the transcriptional abundance of corresponding genes involved in the biosynthesis pathway of these compounds. The heterologous expression of PabHLH1 in Arabidopsis thaliana resulted in the activation of flavonoids and anthocyanins synthesis, involving the up-regulation of structural genes acting both early and late in the flavonoids synthesis pathway. The transcription level of PabHLH1 in P. appendiculatum thallus responded positively to stress induced by either exposure to UV radiation or treatment with salicylic acid. CONCLUSION: PabHLH1 was involved in the regulation of the biosynthesis of flavonoids as well as bibenzyls in liverworts and stimulated the accumulation of the flavonols and anthocyanins in Arabidopsis.

2.
J Asian Nat Prod Res ; : 1-6, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31566431

RESUMO

Two new naphthoate derivatives, including a symmetrical dimer (1) and a monomer (2), were separated from the roots of Morinda officinalis var. hirsuta. Their structures were characterized on the basis of spectroscopic means especially MS and NMR methods. Biological evaluations revealed that the two compounds did not show inhibition against both cholinesterases AChE and BChE, while the dimer (1) did exhibit moderate growth inhibitory activity toward one human osteosarcoma cell line U2OS with an IC50 value of 18.5 ± 1.1 µM.

3.
Food Funct ; 10(10): 6473-6483, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31531441

RESUMO

The aroma of grilled eel is affected by three key processing steps: curing, steaming, and grilling. This study was aimed at the determination of the difference between the characteristic volatiles in each processing stage and their influence on the final aroma of grilled eel. A total of 92 volatile compounds were identified by purge and trap (P&T) combined with gas chromatography-mass spectrometry (GC-MS) throughout the processing. Alcohol, ketone, aromatic compounds and methylated compounds were the most important volatiles in the eel meat during processing. Pyrazine was generated gradually during the entire process, and 2,3-dimethylpyrazine was only found in the sample after grilling. Distinct odors among the raw and treated samples could be indirectly distinguished according to their volatile compounds, analyzed by heatmap. Together, these results indicate a relationship between the final aroma and the whole processing. The odor coding made from the odor activity value (OAV) could be as a reference benchmark for the grilled eel product.

4.
Bioorg Chem ; 92: 103196, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31445194

RESUMO

Eleven new highly oxygenated germacrane-type sesquiterpenoids (1-11) and 16 known analogues (12-27) were isolated from the aerial parts of Sigesbeckia orientalis. Their structures, including absolute configurations, were determined by comprehensive spectroscopic methods especially NMR and ECD analyses. Compounds 13, 21 and 23 possessing an 8-methacryloxy group showed stronger in vitro cytotoxicity against human A549 and MDA-MB-231 cancer cell lines than other co-metabolites, with IC50 values ranging from 6.02 to 10.77 µM comparable to the positive control adriamycin.

5.
J Agric Food Chem ; 67(31): 8677-8688, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31293164

RESUMO

Reversed-phase ultrahigh-performance-liquid chromatography-mass spectrometry (UPLC-MS) is the typical method for the lipidomic analysis of most of biological samples, which was rarely used for the comprehensive lipidomic analysis of marine shellfish. Thus, a range of columns, modifiers, and resuspension solvents were evaluated using UPLC-electrospray ionization-quadrupole time-of-flight-MS to facilitate the ionization efficiency in both the positive and negative electrospray ionization (ESI(+)/(-)) modes for abalone lipids. Optimal lipidomic coverage was acquired with 10 mM ammonium formate in both ESI(+)/(-) modes. The selected resuspension solvents also influenced ionization efficiency through the matrix effect, and resuspension in methanol enhanced the signal intensities by reducing ion suppression. Because of the higher glycerophospholipid content in shellfish, bridged ethylene hybrid C8 columns showed clear advantages over charged surface hybrid C18 columns. A series of glycerophospholipids, lyso-glycerophospholipids, glycerolipids, and fatty acids in different shellfish can be annotated and semiquantified in one injection by the optimized method.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Lipídeos/química , Frutos do Mar/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Cromatografia Líquida de Alta Pressão/instrumentação , Ácidos Graxos/química , Glicerofosfolipídeos/química , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Espectrometria de Massas em Tandem
6.
J Ovarian Res ; 12(1): 60, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31277702

RESUMO

OBJECTIVE: To investigate whether miR-203a-3p can regulate the biological behaviors of ovarian cancer cells by targeting ATM to affect the Akt/GSK-3ß/Snail signaling pathway. METHODS: The expression levels of miR-203a-3p and ATM were detected by qRT-PCR, immunohistochemical staining and Western blotting in ovarian cancer tissues and adjacent normal tissues obtained from 152 subjects. A dual-luciferase reporter gene assay was performed to verify the relationship between miR-203a-3p and ATM. Human ovarian cancer cell lines (A2780 and SKOV3) were used to generate the Blank, miR-NC, miR-203a-3p mimic, Control siRNA, ATM siRNA, and miR-203a-3p inhibitor + ATM siRNA groups. The biological behaviors of ovarian cancer cells were evaluated by CCK-8, wound healing, and Transwell invasion assays, annexin V-FITC/PI staining and flow cytometry. The levels of Akt/GSK-3ß/Snail pathway-related proteins were assessed by Western blotting. RESULTS: Ovarian cancer tissues showed lower miR-203a-3p levels and higher ATM levels than adjacent normal tissues, both of which were associated with the FIGO stage, grade and prognosis of ovarian cancer. As confirmed by a dual-luciferase reporter gene assay, miR-203a-3p could target ATM. Furthermore, the miR-203a-3p mimic had multiple effects, including the inhibition of the proliferation, invasion and migration of A2780 and SKOV3 cells, the promotion of cell apoptosis, the arrest of the cell cycle at the G1 phase, and the blockage of the Akt/GSK-3ß/Snail signaling pathway. ATM siRNA had similar effects on the biological behaviors of ovarian cancer cells, and these effects could be reversed by a miR-203a-3p inhibitor. CONCLUSION: miR-203a-3p was capable of hindering proliferation, migration, and invasion and facilitating the apoptosis of ovarian cancer cells through its modulation of the Akt/GSK-3ß/Snail signaling pathway by targeting ATM, and therefore it could serve as a potential therapeutic option for ovarian cancer.

7.
J Agric Food Chem ; 67(25): 7174-7182, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31240931

RESUMO

Intake of endocrine-disrupting chemicals (EDCs) by humans could disturb the metabolism of hormones, induce cancer, and damage the liver and other organs. Phthalate acid esters (PAEs) and alkylphenols (APs) are important EDCs and environmental contaminants. With the increasing use of plastics and nonionic surfactants worldwide, PAEs and APs have entered environmental water and accumulated in edible fish, which are finally consumed by humans. In this study, a coated direct inlet probe (CDIP) based on an atmospheric solid analysis probe, which can rapidly and simultaneously extract both PAEs and APs in fish, was developed. Twelve PAEs and APs were quantified by using a stable-isotope-labeled internal standard. Standard curves of the PAEs and APs having correlation coefficients of R2 ≥ 0.9837 were obtained. The limit of detection of the PAEs and APs was distributed from 0.01 to 40 ng g-1. The relative recovery of the method was 78-120% between low, medium, and high spiked levels. Combined with principal component analysis, PAE- and AP-contaminated Carassius auratus from different habitats could be identified. Multiple sample analysis mode allowed the extraction of up to 12 samples at once, and the total analysis time (including sample pretreatment, extraction, and analysis time) was less than 10 min per sample, which indicates that CDIP is useful for rapid quantitative analysis.


Assuntos
Ésteres/análise , Carpa Dourada , Ensaios de Triagem em Larga Escala/métodos , Fenóis/análise , Ácidos Ftálicos/análise , Animais , Disruptores Endócrinos/análise , Disruptores Endócrinos/isolamento & purificação , Ésteres/isolamento & purificação , Carpa Dourada/metabolismo , Ensaios de Triagem em Larga Escala/instrumentação , Limite de Detecção , Fenóis/isolamento & purificação , Ácidos Ftálicos/isolamento & purificação , Extração em Fase Sólida
8.
J Chromatogr A ; 1601: 300-309, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31047656

RESUMO

Gas chromatography-mass spectrometry (GCMS) has been extensively used in complex sample analysis for the high-throughput characterization of volatile and semivolatile compounds. However, the accurate extraction of compound information remains challenging. Here, we present a combined algorithm strategy for GCMS data analysis to accurately screen metabolites across groups. First, chromatographic peaks in a total ion chromatogram (TIC) are extracted by using a Gaussian smoothing strategy and aligned on the basis of their mass spectra by a dynamic programing algorithm. The aligned TIC peaks are then registered into a component list table by applying a nearest-neighbor clustering algorithm. Significantly expressed TIC peaks among groups are screened through statistical analysis, such as ANOVA. Second, a chemometric method of multivariate curve resolution-alternating least squares for the peak resolution of the screened TIC peaks is utilized to retrieve the chromatographic and mass spectral profiles of coeluted components. The developed strategy is employed for the analysis of standard and complex plant sample datasets. Results indicate that our methodology is comparable with several state-of-the-art methods that are widely used in GC-MS-based metabolomics.


Assuntos
Algoritmos , Cromatografia Gasosa-Espectrometria de Massas , Metabolômica/métodos , Análise por Conglomerados , Análise dos Mínimos Quadrados , Distribuição Normal
9.
Food Chem ; 286: 241-249, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30827602

RESUMO

This study aimed to determine the changes in the flavor profile during different operating units when making cold-smoked Spanish mackerel. Sensory evaluation and instrumental analysis of tenderness were applied to optimize the processing parameters. For the overall odor perception, distinct odor among fresh and processed samples could be distinguished using electronic nose (e-Nose). Purge-and-trap (P&T) extraction combined with gas chromatography-mass spectrometry (GC-MS) was used to identify volatile compounds. Alcohols were the major volatiles in Spanish mackerel over the whole processing, while 2-butanol was found in the highest concentration. Curing was an effective way to remove fishy odor. Drying decreased the concentration of volatiles, especially sulfur compounds. Odor formation in cold-smoked mackerel could be divided into four steps (curing, drying, cold smoking and heating) as a result of partial least squares discriminant analysis (PLS-DA).


Assuntos
Manipulação de Alimentos , Perciformes/metabolismo , Compostos Orgânicos Voláteis/análise , Álcoois/análise , Animais , Dessecação , Análise Discriminante , Nariz Eletrônico , Cromatografia Gasosa-Espectrometria de Massas , Análise dos Mínimos Quadrados , Odorantes/análise , Temperatura Ambiente , Compostos Orgânicos Voláteis/química
10.
J Chromatogr A ; 1596: 20-29, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-30885403

RESUMO

The coated direct inlet probe (CDIP) is a new laboratory-made low-cost technology developed from a direct inlet probe (DIP), which has the advantage of quick enrichment/cleanup of an analyte from liquid samples. A capillary probe is coated with hydroxy-terminated polydimethylsiloxane (OH-PDMS), divinylbenzene (DVB), and ß-cyclodextrin (ß-CD) by a sol-gel method. This probe can be directly coupled with a commercialized atmospheric-pressure chemical ionization (APCI) ion source and high-resolution mass spectrometry, which are widely applicable, reliable, and durable. The ability to perform quantitative analyses with the use of a stable-isotope-labeled internal standard (SIL-IS) was tested by using different concentrations of acenaphthylene (ACY), acenaphthene (ACP), fluorene (FLR), fluoranthene (FLT), phenanthrene (PHE), and benzo[a]pyrene (B[a]P). Calibration curves with a coefficient of determination of R2 ≥ 0.9982 for different polycyclic aromatic hydrocarbons (PAHs) were obtained. A limit of detection (LOD) of 0.008-0.04 ng mL-1 for PAHs was determined. The entire workflow is solvent-free and can be completed in less than 5 min, which demonstrates the advantages of this technique for quantitative analysis.


Assuntos
Técnicas de Química Analítica/instrumentação , Técnicas de Química Analítica/métodos , Espectrometria de Massas , Hidrocarbonetos Policíclicos Aromáticos/análise , Pressão Atmosférica , Calibragem , Limite de Detecção , Espectrometria de Massas/instrumentação
11.
Food Res Int ; 115: 32-43, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599949

RESUMO

Fresh and grilled eel were investigated with respect to their volatile compounds and different fingerprinting techniques. An electronic nose (e-Nose) was applied to distinguish the odor between fresh and grilled eels. Purge and trap (P&T) and solvent-assisted flavor evaporation (SAFE) method were used to extract volatile compounds and further analyzed by a gas chromatographic combined with quadrupole mass spectrometry (GC-MS) and a two-dimensional gas chromatographic combined with hybrid quadrupole time-of-flight mass spectrometry (GC × GC-QTOF). SAFE extracted more ketone, alcohol and high boiling volatiles in eels than P&T. Considering some distinct compounds extracted by P&T, a P&T and SAFE combined method was chosen. There were 155 volatiles detected in fresh and grilled eels, 93 volatiles were identified. Due to the higher peak capacity, GC × GC-QTOF detected 39 compounds more than GC-MS. The key characteristic volatiles of grilled eel were methyl propyl disulfide, dimethyl trisulfide, heptane, octane, and camphene. Volatile fingerprinting can be a reference benchmark for identification and quality appraisal of fresh and grilled eel products.

12.
J Chromatogr A ; 2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30509617

RESUMO

Data analysis for ultra-performance liquid chromatography high-resolution mass spectrometry-based metabolomics is a challenging task. The present work provides an automatic data analysis workflow (AntDAS2) by developing three novel algorithms, as follows: (i) a density-based ion clustering algorithm is designed for extracted-ion chromatogram extraction from high-resolution mass spectrometry; (ii) a new maximal value-based peak detection method is proposed with the aid of automatic baseline correction and instrumental noise estimation; and (iii) the strategy that clusters high-resolution m/z peaks to simultaneously align multiple components by a modified dynamic programing is designed to efficiently correct time-shift problem across samples. Standard compounds and complex datasets are used to study the performance of AntDAS2. AntDAS2 is better than several state-of-the-art methods, namely, XCMS Online, Mzmine2, and MS-DIAL, to identify underlying components and improve pattern recognition capability. Meanwhile, AntDAS2 is more efficient than XCMS Online and Mzmine2. A MATLAB GUI of AntDAS2 is designed for convenient analysis and is available at the following webpage: http://software.tobaccodb.org/software/antdas2.

13.
Int J Mol Med ; 42(5): 2469-2480, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30226564

RESUMO

Endometrial cancer is a life­threatening malignancy that affects women all over the world, and it has an increasing incidence. MicroRNAs (miRNAs/miRs) have been reported to be involved in cellular activities in endometrial cancer. The present study aimed to examine the effects of miR­183­5p on the epithelial­mesenchymal transition (EMT), proliferation, invasion, migration and apoptosis of human endometrial cancer cells by targeting Ezrin. Primary endometrial cancer tissues and adjacent normal tissues were obtained for the investigation. The protein expression of Ezrin in tissues was detected by immunohistochemistry. The expression level of miR­183­5p and the mRNA and protein expression levels of Ezrin and EMT­associated genes were determined by reverse transcription­quantitative polymerase chain reaction and western blot analyses. Endometrial cancer cells were treated with miR­183­5p inhibitors, small interfering RNA targeting Ezrin or miR­183­5p inhibitors. Cell proliferation, cell cycle, apoptosis, migration and invasion were then evaluated using an MTT assay, flow cytometry, scratch test and Transwell assay, respectively. Compared with normal adjacent tissues, the expression of miR­183­5p was decreased in endometrial cancer tissues, and the expression of Ezrin was significantly increased in endometrial cancer tissues. The protein expression of Ezrin was correlated with the severity and poor prognosis of endometrial cancer. Notably, the target prediction program and the luciferase reporter gene assay confirmed that miR­183­5p targeted and negatively regulated the expression of Ezrin. In vivo experiments revealed that the increased expression of miR­183­5p and decreased expression of Ezrin inhibited EMT, cell proliferation, migration and invasion, but promoted cell apoptosis in Ishikawa cells. These results suggested that the upregulated expression of miR­183­5p promoted apoptosis and suppressed the EMT, proliferation, invasion and migration of human endometrial cancer cells by downregulating Ezrin.

14.
Molecules ; 23(8)2018 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-30087276

RESUMO

A series of novel coumarin/2-cyanoacryloyl hybrids were prepared and evaluated for their in vitro anticancer activity. Among them, two analogs 5p and 5q showed promising antiproliferative activity against a panel of cancer cell lines, including A549, H157, HepG2, MCF7, MG63, and U2OS. Particularly, 5q showed the most potent activity towards MG63 cells with an IC50 value of 5.06 ± 0.25 µM. Morphological observation and 4,6-diamidino-2-phenylindole (DAPI) staining assay showed that 5q-treated MG63 cells displayed significant apoptosis characteristics. Moreover, flow cytometric detection of phosphatidylserine externalization revealed that 5q induced MG63 apoptosis in a dose-dependent manner. Real-time PCR and western blot assay further confirmed that 5q had strong effects to induce MG63 cell apoptosis, suggesting that the action was associated with down-regulation of the anti-apoptotic protein Bcl-2, upregulation of pro-apoptotic protein Bax, and induced activation of caspase-3, 8, and 9. The present results provide a new chemotype for anticancer drug development and continuing investigation into candidates with coumarin/2-cyanoacryloyl scaffold is warranted.


Assuntos
Apoptose/efeitos dos fármacos , Caspases/metabolismo , Cumarínicos/síntese química , Cumarínicos/farmacologia , Cianoacrilatos/síntese química , Cianoacrilatos/farmacologia , Desenho de Drogas , Transdução de Sinais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Cumarínicos/química , Cianoacrilatos/química , Ativação Enzimática/efeitos dos fármacos , Humanos , Transdução de Sinais/efeitos dos fármacos
15.
Food Chem ; 265: 49-56, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29884393

RESUMO

Abalone has been farmed commercially for the last few decades, and the breeding and economic value of abalone have gained extensive attention. In this study, the lipid profile of the foot muscles, viscera, and gonads of male and female Japanese abalone Haliotis discus hannai Ino was explored using ultra performance liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry (UPLC-ESI-Q-TOF-MS), to discuss the effect of lipid composition on its nutritional value. Thirty-four species from ten lipid classes including phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylglycerol, phosphatidic acid, lysophosphatidic acid, triacylglycerol, steroids, terpenoids and fatty acids were annotated by MS-DIAL to obtain all fragment ions for precursors. Glycerophospholipids (GPLs) enriched in unsaturated fatty acids were the major components, which accounted for 52-57% of total lipids. Considering the high-level of GPLs, and their importance in maintaining the integrity and functionality of cell membranes, further utilization of inexpensive tissues, such as viscera and gonads is warranted.


Assuntos
Gastrópodes/química , Lipídeos/química , Espectrometria de Massas por Ionização por Electrospray , Animais , Membrana Celular/química , Membrana Celular/metabolismo , Cromatografia Líquida de Alta Pressão , Gastrópodes/citologia , Espectrometria de Massas em Tandem
16.
New Phytol ; 217(2): 909-924, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29083033

RESUMO

Flavonoids ubiquitously distribute to the terrestrial plants and chalcone isomerase (CHI)-catalyzed intramolecular and stereospecific cyclization of chalcones is a committed step in the production of flavonoids. However, so far the bona fide CHIs are found only in vascular plants, and their origin and evolution remains elusive. We conducted transcriptomic and/or genomic sequence search, subsequent phylogenetic analysis, and detailed biochemical and genetic characterization to explore the potential existence of CHI proteins in the basal bryophyte liverwort species and the lycophyte Selaginella moellendorffii. We found that both liverwort and Selaginella species possess canonical CHI-fold proteins that cluster with their corresponding higher plant counterparts. Among them, some members exhibited bona fide CHI activity, which catalyze stereospecific cyclization of both 6'-hydroxychalcone and 6'-deoxychalcone, yielding corresponding 5-hydroxy and 5-deoxyflavanones, resembling the typical type II CHIs currently known to be 'specific' for legume plants. Expressing those primitive bona fide CHIs in the Arabidopsis chi mutant restores the seed coat transparent testa phenotype and the accumulation of flavonoids. These findings, in contrast to our current understanding of the evolution of enzymatic CHIs, suggest that emergence of the bona fide type II CHIs is an ancient evolution event that occurred before the divergence of liverwort lineages.

17.
Bioorg Med Chem Lett ; 27(20): 4682-4686, 2017 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28919340

RESUMO

Twenty-five novel pregnenolone/2-cyanoacryloyl conjugates (6-30) were designed and prepared, with the aim of developing novel anticancer drugs with dual NF-κB inhibitory and anti-proliferative activities. Compounds 22 and 27-30 showed inhibition against TNF-α-induced NF-κB activation in luciferase assay, which was confirmed by Western blotting. Among them, compound 30 showed potent NF-κB inhibitory activity (IC50=2.5µM) and anti-proliferative against MCF-7, A549, H157, and HL-60 cell lines (IC50=6.5-36.2µM). The present study indicated that pregnenolone/2-cyanoacryloyl conjugate I can server asa novel scaffold for developing NF-κB inhibitors and anti-proliferative agents in cancer chemotherapy.


Assuntos
Antineoplásicos/síntese química , Cianoacrilatos/química , Desenho de Drogas , NF-kappa B/metabolismo , Pregnenolona/química , Células A549 , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Células MCF-7 , NF-kappa B/antagonistas & inibidores , Relação Estrutura-Atividade
18.
Food Chem ; 232: 633-638, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28490121

RESUMO

The objective of this study was to develop an accurate, robust and rapid HPLC-MS/MS-based method capable of quantifying acrylamide and 5-hydroxymethylfurfural (HMF) simultaneously. A Phenomenex Synergi Fusion-RP C18 column (50mm×2.5mm, 2µm) was used, and the MS/MS instrument was operated in multiple reaction monitoring mode. The isotope dilution method was used to correct for the matrix effect from samples. This method demonstrated low limits of quantification (2.12ng/mL for acrylamide and 4.86ng/mL for HMF) and excellent linearity (R2>0.999). This method also demonstrated excellent quantification accuracy, precision, and recovery (87-110%). Using the method developed, target analytes were quantified in 14 thermally-processed seafood samples. Resulting concentrations ranged from 5.58 to 50.35µg/kg for acrylamide, and from 12.54 to 2276.44µg/kg for HMF. The proposed isotope dilution HPLC-MS/MS method is a valid and rapid technique for simultaneous analysis of acrylamide and HMF in seafood.


Assuntos
Acrilamida , Furaldeído/análogos & derivados , Alimentos Marinhos , Cromatografia Líquida de Alta Pressão , Isótopos , Espectrometria de Massas em Tandem
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(1): 227-31, 2017 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-30221502

RESUMO

In order to expand the application range of the model for a single kind of fruits in the portable near infrared instrument, this paper comes up with a new method for the soluble solid content (SSC) model transfer between different kinds of fruits. This method is focusing on the idea of model transfer between different instruments. Based on the similar physical and chemical properties of apples, peaches and pears, such as the range of SSC content, fruit size and the thickness of peel, a simple Slope/Bias algorithm is applied to the transfer of apple SSC partial least square (PLS) model. After that, it can be used to predict pear & peach SSC value with very little extra samples. It's more convenient and costs less by using this method. For pear samples, by using extra 35 standard samples to transfer apple SSC model, RMSEP reduced from 1.009 °Brix to 0.565 °Brix. For peaches, extra 40 standard samples led to a significant reduce of RMSEP from 1.726 °Brix to 0.677 °Brix after model transfer. To validate the feasibility of this model transfer method, both pear and peach SSC models were tested using the same Slope/Bias algorithm model transfer respectively. A pear SSC model was firstly set up and then transferred with Slope/Bias method. Taking 30 standard apples as samples, RMSEP value reached 0.597°Brix, while taking 40 standard peaches as samples, RMSEP value reached 0.689°Brix. The peach SSC model was transferred in the same way. For apples, using 35 standard samples, RMSEP value reached 0.654°Brix, and for pears, using 30 standard samples, RMSEP value reached 0.439°Brix. These results show that slope/bias algorithm can be used to transfer model between similar kinds of fruits such as apples, pears and peaches. The paper provides innovative ideas for the model transfer among similar kinds of materials, so that the portable near infrared instruments can be used more conveniently and widely.

20.
Chin Med J (Engl) ; 129(24): 2991-2997, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27958232

RESUMO

OBJECTIVE: The arrival of precision medicine plan brings new opportunities and challenges for patients undergoing precision diagnosis and treatment of malignant tumors. With the development of medical imaging, information on different modality imaging can be integrated and comprehensively analyzed by imaging fusion system. This review aimed to update the application of multimodality imaging fusion technology in the precise diagnosis and treatment of malignant tumors under the precision medicine plan. We introduced several multimodality imaging fusion technologies and their application to the diagnosis and treatment of malignant tumors in clinical practice. DATE SOURCES: The data cited in this review were obtained mainly from the PubMed database from 1996 to 2016, using the keywords of "precision medicine", "fusion imaging", "multimodality", and "tumor diagnosis and treatment". STUDY SELECTION: Original articles, clinical practice, reviews, and other relevant literatures published in English were reviewed. Papers focusing on precision medicine, fusion imaging, multimodality, and tumor diagnosis and treatment were selected. Duplicated papers were excluded. RESULTS: Multimodality imaging fusion technology plays an important role in tumor diagnosis and treatment under the precision medicine plan, such as accurate location, qualitative diagnosis, tumor staging, treatment plan design, and real-time intraoperative monitoring. Multimodality imaging fusion systems could provide more imaging information of tumors from different dimensions and angles, thereby offing strong technical support for the implementation of precision oncology. CONCLUSION: Under the precision medicine plan, personalized treatment of tumors is a distinct possibility. We believe that multimodality imaging fusion technology will find an increasingly wide application in clinical practice.


Assuntos
Imagem Multimodal/métodos , Neoplasias/diagnóstico , Medicina de Precisão/métodos , Humanos
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