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1.
Carbohydr Polym ; 339: 122239, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823909

RESUMO

A new zirconium and cerium-modified polyvinyl alcohol (PVA) sodium carboxymethyl cellulose (NaCMC) film (PVA/CMC-Zr-Ce) was synthesized thru a high-speed shear-assisted method and its adsorption for the removal of fluoride was studied, in which the NaCMC provided -COONa for ion exchange between Na and Zr-Ce, thus the loading amount of Zr-Ce on films was accordingly increased. The morphology and structure of PVA/CMC-Zr-Ce were characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). Besides, the mechanical properties, water contact angle, and swelling ratio of film were also evaluated. The addition of high-speed shear improved the dispersion of the emulsion system, and PVA/CMC-Zr-Ce film with good adsorption performance and film stability was prepared. While, it was found that the adsorption capacity could reach 67.25 mg/g and equilibrium time could reach 20 min. The adsorption mechanism of PVA/CMC-Zr-Ce revealed that ion exchange between hydroxide and fluoride, electrostatic interactions and complexation were the dominating influencing factors. Based on these findings, it can be concluded that PVA/CMC-Zr-Ce film- synthesized with high-speed shear assistance technique is a promising adsorbent for fluoride removal from water.

2.
Cell Div ; 19(1): 12, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38610003

RESUMO

BACKGROUND: Exploring novel biomarkers for gastric cancer holds promise for enhancing patients' therapy and survival rates. lncRNAs and miRNAs have emerged as important biomarkers for various human cancers. However, the role of lncRNA RMST (RMST) in gastric cancer development and the mechanism underlying its function remains unclear. RESULTS: Significant upregulation of RMST was observed in gastric cancer tumor tissues. RMST levels showed strong correlation with patients' lymph node metastasis and TNM stage and serving as a predictor of adverse prognosis RMST negatively regulated miR-204-5p, which in turn mediated the inhibitory effects of RMST knockdown on gastric cancer cell growth and metastasis. CONCLUSION: RMST served as both a prognostic biomarker and tumor promoter by modulating miR-204-5p. Inhibiting RMST could represent a novel and potential therapeutic strategy for gastric cancer.

3.
Int J Biol Macromol ; 259(Pt 1): 129247, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199530

RESUMO

The molecular motion of starch at different glycerol concentrations (0, 20, 50, and 80 %) was investigated using Electron Paramagnetic Resonance (EPR) spectroscopy. Fourier-transform infrared (FTIR) spectroscopy and 1H nuclear magnetic resonance (1H NMR) spectroscopy confirmed that hydroxyl groups at the C2 and C3 positions of glucose units in corn starch (CS), waxy corn starch (WCS), and high amylose corn starch (HCS) were labeled with 4-amino-TEMPO. The crystallinities of CS, WCS, and HCS after spin-labeling decreased from 30.68 % to 3.21 %, 39.36 % to 1.65 %, and 28.54 % to 8.08 %, respectively. The pseudoplastic fluid properties of the spin-labeled starch remained shear-thin at different glycerol concentrations. EPR revealed the fast- and slow-motion components of the spin-labeled starch molecules dispersed in water. At a glycerol concentration of 20 %, the slow-motion component disappeared, indicating a faster rotational motion of the starch chain segments. As the glycerol concentration increased to 50 and 80 %, the rotational motion slowed because of high viscosity. In particular, the mobility of the spin-labeled WCS chains increased owing to easier access of glycerol and water to the branched structure. This study directly observed the dynamics of the molecular behavior of starch in glycerol-water systems.


Assuntos
Glicerol , Amido , Amido/química , Água , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Amilose/química , Marcadores de Spin , Amilopectina
4.
Ecotoxicol Environ Saf ; 266: 115568, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37832482

RESUMO

The tea plant accumulates elevated levels of fluoride (F) from environmental sources. Drinking tea containing high F levels poses a potential threat to human health. Selenium (Se) was applied by foliar spray to investigate its effects on F accumulation and physiology in tea plant. Foliar application of different forms of Se, i.e., Na2SeO3, Kappa-selenocarrageenan, Selenomethionine and Nanoselenium, reduced F content in tea leaves by 10.17 %-44.28 %, 16.12 %-35.41 %, 22.19 %-45.99 % and 22.24 %-43.82 %, respectively. Foliar spraying Se could increase F accumulation in pectin through increasing pectin content and pectin demethylesterification to bind more F in the cell wall, which decreased the proportion of water-soluble fluoride in tea leaves. Application of Se significantly decreased the contents of chromium (39.6 %-72.0 %), cadmium (48.3 %-84.4 %), lead (2.2 %-44.4 %) and copper (14.1 %-44.6 %) in tea leaves. Foliar spraying various forms of Se dramatically increased the Se content and was efficiently transformed into organic Se accounting for more than 80 % in tea leaves. All Se compounds increased peroxidase activity by 3.3 %-35.5 % and catalase activity by 2.6 %-99.4 %, reduced malondialdehyde content by 5.6 %-37.1 %, and increased the contents of chlorophyll by 0.65 %-31.8 %, carotenoids by 0.24 %-27.1 %, total catechins by 1.6 %-21.0 %, EGCG by 4.4 %-17.6 % and caffeine by 9.1 %-28.6 %. These results indicated that Se application could be served as a potential efficient and safe strategy diminishing the concentration of F in tea leaves.


Assuntos
Camellia sinensis , Selênio , Humanos , Selênio/metabolismo , Fluoretos/análise , Antioxidantes/metabolismo , Camellia sinensis/química , Folhas de Planta/metabolismo , Chá , Pectinas/metabolismo
5.
Sci Rep ; 13(1): 14494, 2023 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-37661203

RESUMO

To explore the efficacy and safety of fecal microbiota transplantation (FMT) as a treatment approach for ulcerative colitis (UC), a comprehensive systematic review and meta-analysis of randomized controlled trials was conducted. To collect and evaluate randomized controlled trials of high quality on FMT for UC, we searched a number of databases, including PubMed, Web of Science, Cochrane, Embase, and Medline, for studies published between the establishment of the databases and March 2023. We conducted a meta-analysis of the studies using Review Manager software (version 5.4.1) to determine the differences in rates of remission and adverse reactions between the FMT group and the control group, utilizing the risk ratio (RR) and 95% confidence interval (CI) to combine our findings. A total of 13 randomized controlled trials (RCTs) on the efficacy of FMT in patients with UC were included in the study, in which 580 patients participated, including 293 patients treated with FMT and 287 control subjects. Meta-analysis revealed that clinical remission was significantly better in the FMT group than in the control group [RR = 1.73; 95% CI = (1.41, 2.12); P < 0.00001]; endoscopic remission was significantly better in the FMT group than in the control group [RR = 1.74; 95% CI = (1.24, 2.44); P = 0.001]. Additionally, there were no significant differences in the incidence of adverse reactions between the two groups [RR = 1.00; 95% CI = (0.86, 1.15); P = 0.96]. Fecal microbiota transplantation has shown potential as a therapeutic intervention for inducing clinical remission in ulcerative colitis UC; nevertheless, the attainment of endoscopic remission and the maintenance of long-term remission continue to present challenges. Safety concerns persist throughout the treatment process, necessitating the implementation of measures to augment both safety and success rates.


Assuntos
Colite Ulcerativa , Humanos , Colite Ulcerativa/terapia , Transplante de Microbiota Fecal/efeitos adversos , Bases de Dados Factuais , MEDLINE , Razão de Chances , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Toxics ; 11(7)2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37505593

RESUMO

4,4'-dinitrocarbanilide (DNC) is a key component and marker residue of nicarbazin, which forms residues in edible tissue and then causes nephrotoxicity and hepatotoxicity in humans if used excessively. To simplify sample preparation and monitor the DNC rapidly and accurately, a comparable icELISA and lateral flow immunoassay (LFIA) was developed in this study. Briefly, the reaction parameters were explored for improving the sensitivity of icELISA and LFIA. Under the optimal conditions, methanol was selected as the extracting solvent for DNC in chicken, and 20- and 10-fold dilutions of sample extraction eliminated the matrix effect for icELISA and LFIA, separately. After sample pretreatment, the analysis properties of icELISA and LFIA were compared. The limit of detection of icELISA for DNC was 0.8 µg/kg, and the visual and quantitative limits of detection of LFIA were 8 and 2.5 µg/kg. Compared with icELISA, LFIA showed lower sensitivity but obvious advantages in terms of matrix tolerance and detection time (within 15 min). The sensitivity, specificity, and accuracy of the developed assays satisfied the detection requirement even if using simple sample pretreatment. This comparable icELISA and LFIA provided mutual verifiability methods for the accurate detection of DNC in chicken.

7.
Food Chem ; 425: 136538, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37300997

RESUMO

The narrow geographical traceability of green tea is both important and challenging. This study aimed to establish multi-technology metabolomic and chemometric approaches to finely discriminate the geographic origins of green teas. Taiping Houkui green tea samples were analyzed by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry and 1H NMR of polar (D2O) and non-polar (CDCl3). Common dimension, low-level and mid-level data fusion approaches were tested to verify if the combination of several analytical sources can improve the classification ability of samples from different origins. In assessments of tea from six origins, the single instrument data test set results in 40.00% to 80.00% accuracy. Data fusion improved single-instrument performance classification with mid-level data fusion to obtain 93.33% accuracy in the test set. These results provide comprehensive metabolomic insights into the origin of TPHK fingerprinting and open up new metabolomic approaches for quality control in the tea industry.


Assuntos
Chá , Compostos Orgânicos Voláteis , Chá/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Quimiometria , Espectroscopia de Prótons por Ressonância Magnética , Compostos Orgânicos Voláteis/análise
8.
Int J Biol Macromol ; 243: 125155, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37268075

RESUMO

A novel and easily separable adsorbent in the shape of a membrane for the rapid removal of fluoride from water was prepared after testing Zr, La and LaZr to modify a chitosan/polyvinyl alcohol composite adsorbent (CS/PVA-Zr, CS/PVA-La, CS/PVA-LA-Zr). The CS/PVA-La-Zr composite adsorbent can remove a large amount of fluoride within 1 min of contact time, and the adsorption equilibrium can be reached within 15 min. The fluoride adsorption behavior of the CS/PVA-La-Zr composite can be described by pseudo-second-order kinetics and Langmuir isotherms models. The morphology and structure of the adsorbents were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The adsorption mechanism was studied using Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), and which showed that ion exchange occurred mainly with hydroxide and fluoride ions. This study showed that an easily operable, low-cost and environmentally friendly CS/PVA-La-Zr has the potential to remove fluoride effectively from drinking water in a short time.


Assuntos
Quitosana , Água Potável , Poluentes Químicos da Água , Fluoretos/química , Quitosana/química , Álcool de Polivinil , Lantânio/química , Zircônio/química , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Cinética , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/química
9.
Food Chem ; 423: 136305, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37178597

RESUMO

Huajiao is a highly valued spice that is susceptible to fraudulent adulteration, particularly the addition of edible oils to increase weight and improve color. Nuclear magnetic resonance (1H NMR) and chemometrics were used to analyze 120 huajiao samples adulterated with different types and levels of edible oils. Using untargeted data and partial least squares-discriminant analysis (PLS-DA), the discrimination rate between types of adulteration reached 100% accuracy, and the R2 value of the prediction set for the level of adulteration using the targeted analysis dataset combined with PLS-regression methods reached 0.99. Triacylglycerols, major components of edible oils, were identified as a marker of adulteration through the variable importance in projection of the PLS-regression. A quantitative method based on the sn-3 triacylglycerol signal was developed that can achieve a detection limit of 0.11%. Testing of 28 market samples showed adulteration with various edible oils, with adulteration rates ranging from 0.96% to 4.41%.


Assuntos
Zanthoxylum , Espectroscopia de Prótons por Ressonância Magnética , Quimiometria , Óleos de Plantas/análise , Espectroscopia de Ressonância Magnética , Contaminação de Alimentos/análise
10.
Food Chem X ; 18: 100681, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37215200

RESUMO

The effects of different brewing water samples, including natural drinking water (NDW), pure water (PW), mineral water (MW), distilled water (DW), and tap water (TW) on flavor and quality of green tea infusion were investigated. The results showed the dissolution rate of mineral substances varied greatly depend on the type of water used. Notably, the tea infusion brewed with MW showed the highest taste response and darker but higher brightness in color. Furthermore, the content of volatile compounds was highest in tea infusion brewed with NDW and lowest in tea infusion brewed with MW. The mineral substances content and pH were the main factors affecting volatile compounds in green tea infusion. Thereinto, Ca2+ and Fe3+ remarkably affected the content of alcohols and aldehydes in volatile compounds. These results suggested that water with a neutral pH value and lower mineral substance content is more conducive for brewing green tea.

11.
J Adv Res ; 50: 35-54, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36341987

RESUMO

INTRODUCTION: Fluoride is widely presented in drinking water and foods. A strong relation between fluoride exposure and obesity has been reported. However, the potential mechanisms on fluoride-induced obesity remain unexplored. Objectives and methods The effects of fluoride on the obesity were investigated using mice model. Furthermore, the role of gut homeostasis in exacerbation of the obesity induced by fluoride was evaluated. Results The results showed that fluoride alone did not induce obesity in normal diet (ND) fed mice, whereas, it could trigger exacerbation of obesity in high-fat diet (HFD) fed mice. Fluoride impaired intestinal barrier and activated Toll-like receptor 4 (TLR4) signaling to induce obesity, which was further verified in TLR4-/- mice. Furthermore, fluoride could deteriorate the gut microbiota in HFD mice. The fecal microbiota transplantation from fluoride-induced mice was sufficient to induce obesity, while the exacerbation of obesity by fluoride was blocked upon gut microbiota depletion. The fluoride-induced bloom of Erysipelatoclostridium ramosum was responsible for exacerbation of obesity. In addition, a potential strategy for prevention of fluoride-induced obesity was proposed by intervention with polysaccharides from Fuzhuan brick tea. Conclusion Overall, these results provide the first evidence of a comprehensive cross-talk mechanism between fluoride and obesity in HFD fed mice, which is mediated by gut microbiota and intestinal barrier. E. ramosum was identified as a crucial mediator of fluoride induced obesity, which could be explored as potential target for prevention and treatment of obesity with exciting translational value.


Assuntos
Fluoretos , Receptor 4 Toll-Like , Animais , Camundongos , Fluoretos/farmacologia , Dieta Hiperlipídica/efeitos adversos , Obesidade/prevenção & controle
12.
Food Chem ; 403: 134377, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182848

RESUMO

This study developed a simple, rapid, stable, and reliable technique for acrylamide (AAm) detection through surface-enhanced Raman scattering (SERS) on an AgNPs substrate with an aggregating agent. Specifically, the agglomeration effects of five types of salt solutions (NaCl, KCl, MgCl2, Na2SO4, and MgSO4) were investigated at different concentrations and optimized using an orthogonal experiment. The optimal amounts of the aggregating agent, analytes, and AgNPs were 4, 4, and 12 µL, respectively. A linear relationship (peak area I1449 = 7.4197x + 5984.8, R2 = 0.9971) between the characteristic peak area and AAm concentration was established in the range of 10 to 500 µg/L, and the LOD was 2.5 µg/L. The recoveries and relative standard deviations in the analysis of potato chips samples were 94.67 %-117.50 % and 8.43 %-12.29 %, respectively. The results of the proposed method were consistent with those obtained by LC-MS/MS method. This study demonstrated that SERS has excellent potential for application in the qualitative and quantitative analyses of AAm in fried foods.


Assuntos
Acrilamida , Nanopartículas Metálicas , Acrilamida/análise , Análise Espectral Raman/métodos , Cromatografia Líquida , Espectrometria de Massas em Tandem , Contaminação de Alimentos/análise , Nanopartículas Metálicas/análise
13.
Foods ; 12(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38231785

RESUMO

American ginseng (Panax quinquefolius L.) is known for its health benefits, which are attributed to various terpenoids. However, the specific composition and activities of these terpenoids in forest-grown wild American ginseng remain understudied. This study aimed to characterize the terpenoid composition, particularly triterpene saponins, in forest-grown wild American ginseng. The analysis revealed that triterpene saponins, notably American ginseng ginsenosides (AGGs), are the predominant active components, as identified through LC-MS/MS and HPLC. A subsequent in vitro evaluation of AGGs showcased their potent antioxidant capabilities, displaying the dose-dependent scavenging of free radicals and reducing agents. Moreover, AGGs demonstrated efficacy in reducing oxidative injury and intracellular ROS levels in RAW 264.7 macrophages treated with H2O2. In addition to their antioxidant properties, AGGs exhibited anti-inflammatory effects, significantly inhibiting NO and inflammatory substance production in lipopolysaccharide-treated RAW 264.7 macrophages. These findings highlight the potential of AGG-rich forest-grown wild American ginseng as a functional food with promising implications for improving human health.

14.
Foods ; 11(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36076836

RESUMO

Rongalite was reported illegally used as a food additive for bleaching purposes and improving the tenderness of foodstuffs, which may endanger public health. At present, rongalite was mostly detected by indirect methods via derivatization or determining its decomposition products. In this study, we developed a new fluorescence sensor for the direct quantification of rongalite based on the principles: (1) dopamine reacts with resorcinol and generates strong fluorophore (azamonardine); (2) rongalite could inhibit the production of fluorophores and then result in lower fluorescence intensity. Hence, the rongalite concentration was inversely proportional to fluorescence intensity of fluorophore. Several crucial reaction conditions of fluorescence sensor were further optimized, such as dopamine and resorcinol concentration, pH values, and reaction time. Under the optimal conditions, the limit of detection of fluorescence sensor was 0.28-0.38 µg/g in vermicelli, wheat and rice powder samples, exhibiting almost 3.5-fold improvement compared to that of lateral flow immunoassay. Moreover, the detection time was substantially decreased to 20 min. The recoveries in spiked samples were 80.7-102.1% with a coefficient of variation of less than 12.6%. In summary, we developed a direct, high throughput, selective and accurate fluorescence sensor that poses a promising application for the rapid detection of rongalite in foodstuffs.

15.
Biosensors (Basel) ; 12(9)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36140130

RESUMO

Tea is an important economic crop and health beverage in China. The presence of heavy metal ions in tea poses a significant threat to public health. Here, we prepared an aptamer biosensor labelled with AIEgen nanospheres to detect Pb2+ in tea. The dsDNA modified by amino and phosphoric acid was combined with the carboxylated AIEgen NPs to form AIEgen-DNA with a fluorescence group, which was then fixed to the surface of Zr-MOFs to quench the fluorescence of AIEgen NPs. At the same time, PEG was added to remove nonspecific adsorption. Then Pb2+ was added to cut the DNA sequences containing the cutting sites, and AIEgen NPs and part of the DNA sequences were separated from the Zr-MOFs surface to recover the fluorescence. By comparing the fluorescence changes before and after adding Pb2+, the detection limit of Pb2+ can reach 1.70 nM. The fluorescence sensor was applied to detect Pb2+ in tea, and the detection results showed that the tea purchased on the market did not contain the concentration of Pb2+ within the detection range. This study provides new insights into monitoring food and agriculture-related pollutants based on fluorescent biosensors.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Poluentes Ambientais , Nanosferas , Técnicas Biossensoriais/métodos , DNA , Íons , Chumbo , Chá
16.
J Chromatogr A ; 1676: 463284, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35792442

RESUMO

American ginseng (Panax quinquefolius L.) is protected by Geographical Indications as harvested roots have different regional characteristics. The aim of this study was to distinguish 95 American ginseng samples from four origins (including America, Canada, Shandong province and the Northeast provinces in China), and to further discriminate samples harvested within the protected designation of origin (PDO) from those harvested in non-PDO regions. Two metabolomic methods were used to acquire qualitative data on the metabolites of American ginseng samples from different origins, namely high-performance liquid chromatography (HPLC) and headspace-gas chromatography-mass spectrometry (HS-GC-MS). There were significant differences in numerous metabolites, including volatile compounds and ginsenosides. American ginsengs from four different regions were discriminated based on 25 volatile compounds and 8 ginsenosides using linear discriminant analysis (LDA), which had a 96.8% accuracy and a 74.7% cross validation rate, and random forest (RF) modeling, which reached 100% accuracy using the training set and 92.9% accuracy using the testing set. The same 33 analytes combined with LDA and RF were compared for discrimination of PDO and non-PDO samples. The 100% accuracy was again obtained using the RF model, but only when using data from both HS-GC-MS and HPLC. The result showed that chemical composition combined with chemometric is effectively and accurately to study the origins of American ginseng.


Assuntos
Ginsenosídeos , Panax , Quimiometria , Cromatografia Líquida de Alta Pressão/métodos , Ginsenosídeos/análise , Panax/química , Raízes de Plantas/química
17.
Food Res Int ; 158: 111512, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35840220

RESUMO

Geographic-label is a remarkable feature for Chinese tea products. In this study, the UHPLC-Q/TOF-MS-based metabolomics approach coupled with chemometrics was used to determine the five narrow-geographic origins of Keemun black tea. Thirty-nine differentiated compounds (VIP > 1) were identified, of which eight were quantified. Chemometric analysis revealed that the linear discriminant analysis (LDA) classification accuracy model is 91.7%, with 84.7% cross-validation accuracy. Three machine learning algorithms, namely feedforward neural network (FNN), random forest (RF) and support vector machine (SVM), were introduced to improve the recognition of narrow-geographic origins, the performances of the model were evaluated by confusion matrix, receiver operating characteristic curve (ROC) and area under the curve (AUC). The recognition of RF, SVM and FNN for Keemun black tea from five narrow-geographic origins were 87.5%, 94.44%, and 100%, respectively. Importantly, FNN exhibited an excellent classification effect with 100% accuracy. The results indicate that metabolomics fingerprints coupled with chemometrics can be used to authenticate the narrow-geographic origins of Keemun black teas.


Assuntos
Camellia sinensis , Chá , Algoritmos , Cromatografia Líquida de Alta Pressão , Aprendizado de Máquina , Metabolômica
18.
J Sci Food Agric ; 102(13): 6123-6130, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35474316

RESUMO

BACKGROUND: Most studies focus on the geographically larger production areas in tea traceability. However, famous high-quality tea is often produced in a narrow range of origins, which makes traceability a challenge. In this study, Taiping Houkui (TPHK) green tea of narrow geographical origin was rapidly identified using Fourier-transform near-infrared (FT-NIR) spectroscopy. RESULTS: First, spectral information of 114 TPHK samples from four production areas was acquired. Second, the synthetic minority over-sampling technique (SMOTE) was used to balance the sample data set, and three different spectral pre-processing methods were compared. Third, three feature variable selection algorithms were used to obtain the pre-processed spectral features. Finally, extreme learning machine (ELM) models based on the variables obtained from the selected features were established to trace the TPHK origin. The optimized ELM model achieves 95.35% classification accuracy in the test set. CONCLUSION: The present study demonstrates that the optimized variable selection method in combination with NIR spectroscopy represents a suitable strategy for tea traceability in narrow regions. © 2022 Society of Chemical Industry.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho , Chá , Algoritmos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Chá/química
19.
Hepatology ; 75(4): 968-982, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34662439

RESUMO

BACKGROUND AND AIMS: Lipoprotein Z (LP-Z) is an abnormal free cholesterol (FC)-enriched LDL-like particle discovered from patients with cholestatic liver disease. This study aims to define the diagnostic value of LP-Z in alcohol-associated hepatitis (AH) and interrogate the biology behind its formation. APPROACH AND RESULTS: We measured serum levels of LP-Z using nuclear magnetic resonance spectroscopy, a well-established clinical assay. Serum levels of LP-Z were significantly elevated in four AH cohorts compared with control groups, including heavy drinkers and patients with cirrhosis. We defined a Z-index, calculated by the ratio of LP-Z to total apolipoprotein B-containing lipoproteins, representing the degree of deviation from normal VLDL metabolism. A high Z-index was associated with 90-day mortality independent from the Model for End-Stage Liver Disease (MELD) and provided added prognosticative value. Both a Z-index ≤ 0.6 and a decline of Z-index by ≥0.1 in 2 weeks predicted 90-day survival. RNA-sequencing analyses of liver tissues demonstrated an inverse association in the expression of enzymes responsible for the extrahepatic conversion of VLDL to LDL and AH disease severity, which was further confirmed by the measurement of serum enzyme activity. To evaluate whether the FC in LP-Z could contribute to the pathogenesis of AH, we found significantly altered FC levels in liver explant of patients with AH. Furthermore, FC in reconstituted LP-Z particles caused direct toxicity to human hepatocytes in a concentration-dependent manner, supporting a pathogenic role of FC in LP-Z. CONCLUSIONS: Impaired lipoprotein metabolism in AH leads to the accumulation of LP-Z in the circulation, which is hepatotoxic from excessive FC. A Z-index ≤ 0.6 predicts 90-day survival independent from conventional biomarkers for disease prognostication.


Assuntos
Doença Hepática Terminal , Hepatite Alcoólica , Apolipoproteínas B , Colesterol , Humanos , Lipoproteína(a) , Lipoproteínas , Índice de Gravidade de Doença
20.
Food Chem ; 374: 131713, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-34920400

RESUMO

Tea is one of the most important beverages worldwide, is produced in several distinct geographical regions, and is traded on the global market. The ability to determine the geographical origin of tea products helps to ensure authenticity and traceability. This paper reviews the recent research on authentication of tea using a combination of instrumental and chemometric methods. To determine the production region of a tea sample, instrumental methods based on analyzing isotope and mineral element contents are suitable because they are less affected by tea variety and processing methods. Chemometric analysis has proven to be a valuable method to identify tea. Principal component analysis (PCA) and linear discriminant analysis (LDA) are the most preferred methods for processing large amounts of data obtained through instrumental component analysis.


Assuntos
Camellia sinensis , Quimiometria , Análise Discriminante , Folhas de Planta , Análise de Componente Principal , Chá
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