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1.
Int J Biol Macromol ; 272(Pt 1): 132843, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38830489

RESUMO

The study aimed to inhibit the stimulating impact of garlic oil (GO) on the stomach and attain high release in the intestine during digestion. So, wheat porous starch (WPS) was modified with octenyl succinic acid (OSA) and malic acid (MA) to obtain esterified WPS, OWPS and MWPS, respectively. The differences in physicochemical, encapsulation, and digestive properties of two GO microcapsules, WPI/OWPS/GO and WPI/MWPS/GO microcapsules produced by using OWPS and MWPS as variant carrier materials and whey protein isolate (WPI) as the same coating agent, were compared. The results found that OWPS had greater amphiphilicity, while MWPS had better hydrophobicity and anti-digestive ability than WPS. Encapsulation efficiency of WPI/OWPS/GO (94.67 %) was significantly greater than WPI/MWPS/GO (91.44 %). The digestion inhibition and low GO release (approximately 23 %) of WPI/OWPS/GO and WPI/MWPS/GO microcapsules in the gastric phase resulted from the protective effect of WPI combined with the good adsorption and lipophilicity of OWPS and MWPS. Especially, WPI/OWPS/GO microcapsule was relatively stable in the gastric phase and had sufficient GO release (67.24 %) in the intestinal phase, which was significantly higher than WPI/MWPS/GO microcapsule (56.03 %), benefiting from the adsorption and digestive properties of OWPS, and resulting in a total cumulative GO release rate of 90.86 %.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38568761

RESUMO

The adversarial robustness is critical to deep neural networks (DNNs) in deployment. However, the improvement of adversarial robustness often requires compromising with the network size. Existing approaches to addressing this problem mainly focus on the combination of model compression and adversarial training. However, their performance heavily relies on neural architectures, which are typically manual designs with extensive expertise. In this article, we propose a lightweight and robust neural architecture search (LRNAS) method to automatically search for adversarially robust lightweight neural architectures. Specifically, we propose a novel search strategy to quantify contributions of the components in the search space, based on which the beneficial components can be determined. In addition, we further propose an architecture selection method based on a greedy strategy, which can keep the model size while deriving sufficient beneficial components. Owing to these designs in LRNAS, the lightness, the natural accuracy, and the adversarial robustness can be collectively guaranteed to the searched architectures. We conduct extensive experiments on various benchmark datasets against the state of the arts. The experimental results demonstrate that the proposed LRNAS method is superior at finding lightweight neural architectures that are both accurate and adversarially robust under popular adversarial attacks. Moreover, ablation studies are also performed, which reveals the validity of the individual components designed in LRNAS and the component effects in positively deciding the overall performance.

3.
J Sci Food Agric ; 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38520286

RESUMO

BACKGROUND: Pectin extracted by high-speed shearing from passion fruit peel (HSSP) is a potentially excellent wall material for encapsulating curcumin, which has multiple advantages over pectin prepared by heated water extraction. HSSP was used to fabricate complex nanoparticles of zein-sodium caseinate-pectin for encapsulation of curcumin in this study. The influence of heating on the physicochemical properties of the composite nanoparticles was also investigated, as well as the effect of composite nanoparticles on the encapsulation efficiency, antioxidant activity and release characteristics of curcumin. RESULTS: The nanoparticles were formed through electrostatic interactions, hydrogen bonds and hydrophobic interactions between the proteins and HSSP. A temperature of 50 °C was more favorable for generating compact and small-sized nanoparticles, which could effectively improve the encapsulation efficiency and functional properties. Moreover, compared to other pectin used in the study, the nanoparticles prepared with HSSP showed the best functionality with a particle size of 234.28 ± 0.85 nm, encapsulation rate of 90.22 ± 0.54%, free radical scavenging rate of 78.97% and strongest protective capacity in simulated gastric fluid and intestinal release effect. CONCLUSION: Zein-sodium caseinate-HSSP is effective for encapsulating and delivering hydrophobic bioactive substances such as curcumin, which has potential applications in the functional food and pharmaceutical industries. © 2024 Society of Chemical Industry.

4.
Ultrason Sonochem ; 102: 106746, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38157804

RESUMO

The dry separate curing of duck egg yolks was carried out by ultrasonic synergize NaCl (sodium chloride) and NaCl alone. The mechanism of the amelioration of salted egg yolk quality by ultrasonic synergistic NaCl dry-curing was studied. The quality variations of the salted egg yolks were analyzed for the same curing time and NaCl content achieved by ultrasonic synergistic NaCl curing and NaCl curing alone. The results showed that under the same salting time, the NaCl content, oil exudation and chewiness of U48-SEY (ultrasonic for 48 h-salted egg yolk) were higher than those in SEY (salted egg yolk). At the same NaCl content, the oil exudation and chewiness of U44-SEY (ultrasonic for 44 h-salted egg yolk) were still significantly increased. Compared to SEY, the soluble protein content and H0 of U44-SEY and U48-SEY were augmented. Scanning electron microscopy (SEM) indicated that the polyhedral particles in the salted egg yolks prepared by ultrasonic synergistic NaCl dry-curing were closely aligned and evenly distributed, and the salted egg yolks were sandier. Structural analysis revealed that the secondary and tertiary structures of egg yolk protein were changed although the ultrasonic synergistic NaCl dry-curing did not cause the fragmentation or aggregation of the peptide chain structure. The above results suggested that ultrasonic not only perfected the quality of salted egg yolk by promoting NaCl penetration, but also modified the structures of egg yolk protein by the action of ultrasonic itself, which prominently improved the quality of salted egg yolks.


Assuntos
Gema de Ovo , Cloreto de Sódio , Gema de Ovo/química , Cloreto de Sódio/química , Ultrassom , Proteínas do Ovo/análise , Proteínas do Ovo/química , Microscopia Eletrônica de Varredura
5.
Food Chem X ; 19: 100873, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37745033

RESUMO

To obtain flavor-enriched Tibetan pork products, the impact of oxidation degree on the flavor of Tibetan pork with different cooking methods (microwaving, frying, boiling, and air frying) was evaluated using an E-nose, an E-tongue, GC-MS, and LC-MS. The level of oxidation was lower in M and F and higher in B and AF groups. Hexanal, pentanal, benzaldehyde, 1-octen-3-ol, and 3-hydroxy-2-butanone were identified as significant contributors to cooked samples. The volatile abundance of microwaved, fried, boiled, and air-fried pork was 1.61, 1.22, 1.47, and 1.69 times higher than raw, respectively. Leucine and threonine were detected to be the highest in the AF group, which were 1.30 and 3.60 times greater than RAW, respectively. In summary, oxidation of lipids and proteins caused by cooking treatments was the main source of flavor in cooked Tibetan pork. Air-frying treatment could greatly promote the production of flavor compounds and give unique flavor to Tibetan pork.

6.
Food Sci Technol Int ; : 10820132231183027, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37321629

RESUMO

This study aimed to improve the gel quality of golden threadfin bream (Nemipterus virgatus) sausage by adding sugarcane nanocellulose (SNC) and using high pressure combined with a two-stage heat treatment. The gel strength, textural properties, protein secondary structure, water states, and microstructure were analyzed and compared. The results indicated that the heat treatment was beneficial to stabilizing the protein gel structure, increasing the gel strength and textural quality, and reducing the cooking loss. High-pressure treatment resulted in a decrease of α-helix and an increase of ß-sheet in the protein, forming a dense gel structure, which enhanced the gel strength and the percentage of bound water. The superior hydrophilicity of nanocellulose and its cross-linking with protein increased the percentage of bound water in the gel, which improved the water-holding capacity and mechanical properties. Therefore, the best gel quality was obtained by adding nanocellulose and treating it with high pressure combined with two-stage heating.

7.
Food Chem X ; 17: 100541, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36845518

RESUMO

This study examined the potential of hyperspectral techniques for the rapid detection of characteristic indicators of yak meat freshness during the oxidation of yak meat. TVB-N values were determined by significance analysis as the characteristic index of yak meat freshness. Reflectance spectral information of yak meat samples (400-1000 nm) was collected by hyperspectral technology. The raw spectral information was processed by 5 methods and then principal component regression (PCR), support vector machine regression (SVR) and partial least squares regression (PLSR) were used to build regression models. The results indicated that the full-wavelength based on PCR, SVR, and PLSR models were shown greater performance in the prediction of TVB-N content. In order to improve the computational efficiency of the model, 9 and 11 characteristic wavelengths were selected from 128 wavelengths by successive projection algorithm (SPA) and competitive adaptive reweighted sampling (CARS), respectively. The CARS-PLSR model exhibited excellent predictive power and model stability.

8.
Int J Biol Macromol ; 234: 123692, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36801279

RESUMO

This study aimed to investigate the physicochemical properties of the rice porous starch (HSS-ES) prepared by high-speed shear combined with double-enzymatic (α-amylase and glucoamylase) hydrolysis, and to reveal their mechanism. The analyses of 1H NMR and amylose content showed that high-speed shear changed the molecular structure of starch and increased the amylose content (up to 20.42 ± 0.04 %). FTIR, XRD and SAXS spectra indicated that high-speed shear did not change the starch crystal configuration but caused a decrease in short-range molecular order and relative crystallinity (24.42 ± 0.06 %), and a loose semi-crystalline lamellar, which were beneficial to the followed double-enzymatic hydrolysis. Therefore, the HSS-ES displayed a superior porous structure and larger specific surface area (2.962 ± 0.002 m2/g) compared with double-enzymatic hydrolyzed porous starch (ES), resulting in the increase of water and oil absorption from 130.79 ± 0.50 % and 109.63 ± 0.71 % to 154.79 ± 1.14 % and 138.40 ± 1.18 %, respectively. In vitro digestion analysis showed that the HSS-ES had good digestive resistance derived from the higher content of slowly digestible and resistant starch. The present study suggested that high-speed shear as an enzymatic hydrolysis pretreatment significantly enhanced the pore formation of rice starch.


Assuntos
Amilose , Oryza , Amilose/química , Hidrólise , Oryza/química , Porosidade , Espalhamento a Baixo Ângulo , Difração de Raios X , Amido/química
9.
Food Chem X ; 16: 100494, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36519093

RESUMO

Irradiation's effects on quality, volatile compounds, and differential metabolites of yak meat were studied. Irradiation dose at 3 kGy had no effect on yak meat quality, however irradiation dose at 5 kGy resulted in yak meat quality deterioration as well as considerable irradiated off-flavors. And the level of the off-odor was strongly associated with the irradiation dose, and allyl methyl sulfide, octanal, nonanal, benzaldehyde, and 4-methylthiazole were all significant producers of off-odor. Meanwhile, with the increased of radiation dose, the amounts of cysteine, methionine, proline, linoleic acid, stearic acid changed obviously. The main generation pathway of irradiated off-flavors in yak meat were thought to be cysteine and methionine metabolism, and linoleic acid metabolism. The oxidative decomposition of sulfur-containing amino acids and unsaturated fatty acids may cause the off-flavor of irradiation yak meat. This research established a theoretical foundation for future control systems to prevent flavor quality alterations during irradiation preservation.

10.
Food Chem X ; 16: 100482, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36304206

RESUMO

Potential allergenicity of amandin was reduced by binding amandin with (-)-epigallocatechin gallate (EGCG) via alkaline, free radical, ultrasound-assisted alkaline, and ultrasound-assisted free radical methods. These results of total phenol content, free sulfhydryl group, free amino group, surface hydrophobicity, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) indicated that amandin might be covalently bound to EGCG through reactive groups such as sulfhydryl and amino groups, or non-covalently through hydrophobic interactions. Fourier transformed infrared (FT-IR) spectroscopy and fluorescence spectroscopy revealed structural changes of amandin-EGCG conjugate, which also caused significant reduction in potential allergenicity of amandin. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) found that amandin bound to EGCG mainly through cysteine and glutamate residues, and linear epitope for amandin was reduced. This provided a new method and theoretical basis of hypoallergenic almond food.

11.
Int J Biol Macromol ; 220: 892-900, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35944758

RESUMO

Sugarcane bagasse, a sugar industry waste, has plentiful cellulose. The present work was aimed to prepare the quality nanocellulose with different polymorphs, nanocelluloses I (NC-I) and II (NC-II) utilizing natural deep eutectic solvents (choline chloride and oxalic acid dihydrate) combined with mechanical treatment from purified cellulose (celluloses I and II), which were prepared from sugarcane bagasse, and to further compare the structural and rheological properties of NC-I and NC-II. Results showed that the yields of NC-I and NC-II were 73.66 ± 0.11 % and 75.15 ± 0.08 %, respectively. Morphology indicated that NC-I had a needle-like appearance with a length of 769.9 ± 76.4 nm and a width of 4.9 ± 1.3, while NC-II displayed a rod-like profile with a smaller size (length: 196.3 ± 50.1 nm; width: 14.9 ± 3.8 nm). Structural characterization revealed that both NC-I and NC-II had high purity, good thermal stability (>300 °C) and high crystallinity (85.5 % and 86 %, respectively). Rheological and zeta potential properties revealed that NC-I suspension had bigger shear resistance, viscoelasticity and lower zeta potential, resulting in better storage stability compared with NC-II suspension. Therefore, the NC-I and NC-II with different characteristics may have potential applications in multiple fields, such as the food, pharmaceutical, and chemical industry.


Assuntos
Celulose , Saccharum , Celulose/química , Colina , Solventes Eutéticos Profundos , Ácido Oxálico , Preparações Farmacêuticas , Saccharum/química , Solventes , Açúcares
12.
Food Chem ; 371: 131103, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34537608

RESUMO

Hydroxyl radical system combined with GC-IMS and metabolomics were used to assess the effect of oxidation on the formation of volatile flavor emitted from yak meat. The formation of volatile compounds, including heptanal, octanal, nonanal, 2,3-glutaraldehyde, 3-hydroxy-2-butanone, etc. were promoted by oxidation. Among them, 2,3-pentanedione and 3-hydroxy-2-butanone, etc. maybe contributed most to the overall aroma of yak meat, while octanal, nonanal and benzaldehyde maybe related to the formation of off-odor or acidification. Meanwhile, the content of metabolites such as oleic acid, linoleic acid, etc. fatty acids and 3-dehydromangiferic acid, tyrosine were increased or decreased with the time of oxidation. More importantly, the formation of most flavor components in yak meat during the course of oxidation were related to stearidonic acid, acetylleucine, dehydroshikimate, 6-phosphate-glucose etc. differential metabolic components. Moreover, starch and sucrose metabolism (prediction), and amino acid metabolism (enrichment) etc. pathways maybe related with the process of oxidation.


Assuntos
Compostos Orgânicos Voláteis , Animais , Bovinos , Aromatizantes/análise , Carne , Odorantes/análise , Paladar
13.
Int J Biol Macromol ; 190: 810-818, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34530035

RESUMO

Lophatherum gracile Brongn. (LGB), a homology material of medicine and food, has plentiful cellulose. Aiming to investigate the physiochemical characteristic differences of LGB cellulose extracted by various pretreatment methods and extraction conditions, the effect of dry crushing and wet beating, and the alkaline solution concentration and temperature were compared. Results showed that the extracted cellulose after dry crushing pretreatment had higher purity and lower non-cellulosic components such as hemicellulose, lignin and ash than those obtained by wet beating pretreatment. Furthermore, the impurities were more thoroughly removed by the alkaline solution at high concentration and temperature. Structural characterization revealed that the cellulose obtained by wet beating pretreatment had more fibrillation and smaller particle size, while destroyed crystallinity resulting in bad thermal stability. The alkaline solution temperature had no effect on the morphology and particle size, but high alkaline solution temperature (90 °C) improved crystallinity and thermal stability. Furtherly, the cellulose II produced by at high alkaline solution concentration (18 wt%) exhibited denser surface, smaller particle size and higher thermal stability than the cellulose I extracted at low alkaline solution concentration (4 wt%). Especially, the crystallinity of cellulose II was higher than that of cellulose I with dry crushing pretreatment, while the cellulose obtained by wet beating displayed an opposite trend. Hydration properties indicated that the water holding capacity, oil binding capacity and swelling capacity of the cellulose pretreated by dry crushing were higher than those of the cellulose pretreated by wet beating, and the cellulose I exhibited higher hydration properties compared to the cellulose II, which may depend on its loose network structure. This study suggested that dry crushing pretreatment and high alkaline solution temperature could effectively improve functional properties of LGB cellulose I and II, which promoted its use in food applications.


Assuntos
Celulose/química , Poaceae/química , Hidróxido de Sódio/farmacologia , Temperatura , Celulose/ultraestrutura , Temperatura Alta , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Água/química , Difração de Raios X
14.
Oxid Med Cell Longev ; 2021: 6280690, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33688390

RESUMO

Due to the complexity of medical images, traditional medical image classification methods have been unable to meet the actual application needs. In recent years, the rapid development of deep learning theory has provided a technical approach for solving medical image classification. However, deep learning has the following problems in the application of medical image classification. First, it is impossible to construct a deep learning model with excellent performance according to the characteristics of medical images. Second, the current deep learning network structure and training strategies are less adaptable to medical images. Therefore, this paper first introduces the visual attention mechanism into the deep learning model so that the information can be extracted more effectively according to the problem of medical images, and the reasoning is realized at a finer granularity. It can increase the interpretability of the model. Additionally, to solve the problem of matching the deep learning network structure and training strategy to medical images, this paper will construct a novel multiscale convolutional neural network model that can automatically extract high-level discriminative appearance features from the original image, and the loss function uses the Mahalanobis distance optimization model to obtain a better training strategy, which can improve the robust performance of the network model. The medical image classification task is completed by the above method. Based on the above ideas, this paper proposes a medical classification algorithm based on a visual attention mechanism-multiscale convolutional neural network. The lung nodules and breast cancer images were classified by the method in this paper. The experimental results show that the accuracy of medical image classification in this paper is not only higher than that of traditional machine learning methods but also improved compared with other deep learning methods, and the method has good stability and robustness.


Assuntos
Algoritmos , Atenção/fisiologia , Processamento de Imagem Assistida por Computador/classificação , Redes Neurais de Computação , Neoplasias da Mama/classificação , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem
15.
J Sci Food Agric ; 101(8): 3489-3499, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33274442

RESUMO

BACKGROUND: Prepared chicken breast deterioration is a complex biochemical process, of which protein change is one of the main features. The present research focuses on the analysis of proteins related to the deterioration in quality of prepared chicken breast through differential proteomics analysis. RESULTS: The physicochemical indexes of prepared chicken breast showed that quality gradually decreased at the second week of refrigerated storage, while the deterioration of chicken breast meat was obvious at the third week. Three key time points of quality change were determined to be at 0th, 2th and 5th week, respectively. In addition, 39 differential proteins were successfully identified using two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Most of the identified proteins showed significant differences in expression at the three key points of storage, of which actin, myosin, α-1,4-glucan phosphorylase, phosphoglucomutase 1, heat shock protein ß-1, tubulin ß-7 chain and skeletal muscle type tropomodulin (fragment) were closely related to the quality deterioration of prepared chicken breast, and thus potential indicator proteins to evaluate the quality of chicken breast. CONCLUSION: The current study indicated that the physicochemical quality of prepared breast notably changed during refrigerated storage. Three key time points of quality change in the storage process of prepared chicken breast were determined. Furthermore, differential proteomics identified the key proteins related to freshness, which provides a theoretical basis for exploring the mechanism of chicken breast deterioration. © 2020 Society of Chemical Industry.


Assuntos
Proteínas Aviárias/química , Carne/análise , Animais , Galinhas , Eletroforese em Gel Bidimensional , Armazenamento de Alimentos , Proteoma/química , Proteômica , Refrigeração , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
16.
Front Chem ; 9: 812503, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35004628

RESUMO

In this paper, we developed a quick, economical and sensitive colorimetric strategy for copper ions (Cu2+) quantification via the redox response of MnO2 nanosheets with glutathione (GSH). This reaction consumed MnO2 nanosheets, which acted as a catalyst for the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to a blue product (oxTMB). In the presence of Cu2+, the GSH was catalyzed to GSSG (oxidized glutathione), and the solution changed from colorless to deep blue. Under the optimum conditions, the absorption signal of the oxidized product (oxTMB) became proportional to Cu2+ concentration in the range from 10 to 300 nM with a detection limit of 6.9 nM. This detection system showed high specificity for Cu2+. Moreover, the system has been efficaciously implemented for Cu2+ detection in actual tap water samples. The layered-nanostructures of MnO2 nanosheets make it possess high chemical and thermal stability. TMB can be quickly oxidized within 10 min by the catalyzing of MnO2 nanosheets with high oxidase-like activity. There is no need of expensive reagents, additional H2O2 and complicated modification processes during the colorimetric assay. Therefore, the strategy primarily based on MnO2 nanosheets is promising for real-time, rapid and highly sensitive detection of Cu2+ under practical conditions.

17.
Food Funct ; 11(6): 5621-5634, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32530444

RESUMO

Catechinic acid (CA), widely present in tea and fruits, has vital biological and pharmacological properties. CA plays an important role in the regulation of lifespan. However, the mechanism behind its anti-aging properties remains poorly characterized. In the present study, Caenorhabditis elegans (C. elegans) was used as a model organism. It was found that CA induced mitophagy which prevented the accumulation of dysfunctional mitochondria with age and profoundly extended lifespan. Notably, CA significantly improved the fitness of aging worms, particularly the treatment slowed age-related decline in observed spontaneous movements. Furthermore, CA was found to eliminate dysfunctional mitochondria in the gut and muscle cells, and demonstrated that the lifespan-prolonging effects of CA can be attributed to mitophagy along with the likely regulation of the genes bec-1 and pink-1. The results of this study indicated that pharmacologically induced mitophagy has a profound impact on aging, providing a novel therapeutic intervention against aging and age-related diseases.


Assuntos
Caenorhabditis elegans/fisiologia , Catequina/farmacologia , Longevidade/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Polifenóis/farmacologia , Envelhecimento/fisiologia , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Homeostase , Mitocôndrias/efeitos dos fármacos , Músculos/fisiologia , Interferência de RNA , Resposta a Proteínas não Dobradas
18.
Mikrochim Acta ; 187(6): 329, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32405710

RESUMO

A fluorometric method for the determination of histamine has been developed based on aggregation-induced emission (AIE) effect of D-penicillamine capped copper nanoparticles (DPA-CuNPs). The fluorescent DPA-CuNPs were synthesized by a one-pot method using D-penicillamine as both reducing agent and stabilizing ligand. The size, morphology and physical chemical properties of DPA-CuNPs were examined by transmission electron microscopy (TEM), fluorescence spectroscopy, fourier transform infrared spectroscopy (FTIR) and absorption spectroscopy. The DPA-CuNPs exhibit AIE effect and show intense red fluorescence (650 nm). In the presence of histamine, DPA-CuNPs are dispersed into small homogeneous particles, causing fluorescence quenching. Based on this reaction, a histamine sensor is constructed. The fluorescence of the CuNPs solution has a good linear relationship with histamine concentration in the range 0.05 µM to 5 µM and the determination limit (3σ/slope) is 30 nM. The estimated method was successfully applied to the determination of histamine in fish, pork and red wine. Graphical abstract Schematic representation of copper nanoparticles for histamine analysis. In the presence of histamine, the strong red fluorescence of copper nanoparticles is obvious decreased through interaction of copper nanoparticles and histamine.


Assuntos
Histamina/análise , Nanopartículas Metálicas/química , Penicilamina/química , Animais , Cobre/química , Peixes , Fluorescência , Limite de Detecção , Carne de Porco/análise , Alimentos Marinhos/análise , Espectrometria de Fluorescência , Vinho/análise
19.
Food Res Int ; 130: 108913, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32156363

RESUMO

Iron deficiency anemia (IDA) is a worldwide nutritional problem. The metabolic mechanism of IDA is still unclear. So, the underlying metabolic mechanism of iron supplementation has not been reported even if various iron supplements to treat IDA have been studied. The present study aimed to investigate the metabolic mechanisms of IDA and agar oligosaccharide-iron complex (AOS-iron) supplementation in IDA rats by assessing the changes of endogenous metabolites in serum and liver using LC-MS/MS metabolomics approach. Orthogonal partial least-squares discriminant analysis (OPLS-DA) score plots showed significant separation of metabolites in serum and liver among the normal, anemia model and AOS-iron groups. Seventeen and eight metabolites were identified from serum and liver, respectively. Pathway enrichment analysis suggested that potential biomarkers were strongly involved in the biosynthesis of saturated and unsaturated fatty acids, sphingolipid metabolism, glycerophospholipid metabolism, linoleic acid metabolism, Fcγ receptor (FcγR)-mediated phagocytosis, pancreatic cancer metabolism, regulation of autophagy, gonadotropin releasing hormone (GnRH) signaling pathway, fatty acid metabolism, pantothenate and CoA biosynthesis, glutathione metabolism and primary bile acid biosynthesis. After supplementing 2 mg Fe/kg·bw AOS-iron for 4 weeks, the major metabolites in related pathways disrupted by IDA were restored to normal levels. Therefore, AOS-iron effectively treated IDA by regulating metabolic disorders.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/metabolismo , Ferro/uso terapêutico , Metabolômica/métodos , Espectrometria de Massas em Tandem/métodos , Anemia Ferropriva/sangue , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Cromatografia Líquida/métodos , Modelos Animais de Doenças , Ferro/sangue , Ferro/metabolismo , Masculino , Análise de Componente Principal , Ratos , Ratos Sprague-Dawley
20.
Contrast Media Mol Imaging ; 2019: 6134942, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31481851

RESUMO

With the development of computer vision and image segmentation technology, medical image segmentation and recognition technology has become an important part of computer-aided diagnosis. The traditional image segmentation method relies on artificial means to extract and select information such as edges, colors, and textures in the image. It not only consumes considerable energy resources and people's time but also requires certain expertise to obtain useful feature information, which no longer meets the practical application requirements of medical image segmentation and recognition. As an efficient image segmentation method, convolutional neural networks (CNNs) have been widely promoted and applied in the field of medical image segmentation. However, CNNs that rely on simple feedforward methods have not met the actual needs of the rapid development of the medical field. Thus, this paper is inspired by the feedback mechanism of the human visual cortex, and an effective feedback mechanism calculation model and operation framework is proposed, and the feedback optimization problem is presented. A new feedback convolutional neural network algorithm based on neuron screening and neuron visual information recovery is constructed. So, a medical image segmentation algorithm based on a feedback mechanism convolutional neural network is proposed. The basic idea is as follows: The model for obtaining an initial region with the segmented medical image classifies the pixel block samples in the segmented image. Then, the initial results are optimized by threshold segmentation and morphological methods to obtain accurate medical image segmentation results. Experiments show that the proposed segmentation method has not only high segmentation accuracy but also extremely high adaptive segmentation ability for various medical images. The research in this paper provides a new perspective for medical image segmentation research. It is a new attempt to explore more advanced intelligent medical image segmentation methods. It also provides technical approaches and methods for further development and improvement of adaptive medical image segmentation technology.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Humanos
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