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Search Results (898)

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Keywords = PLS-DA

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13 pages, 1674 KiB  
Article
Chemometric Discrimination of the Geographical Origin of Rheum tanguticum by Stable Isotope Analysis
by Bayan Nuralykyzy, Jing Nie, Guoying Zhou, Hanyi Mei, Shuo Zhao, Chunlin Li, Karyne M. Rogers, Yongzhi Zhang and Yuwei Yuan
Foods 2024, 13(19), 3176; https://doi.org/10.3390/foods13193176 (registering DOI) - 6 Oct 2024
Viewed by 1
Abstract
Rheum tanguticum is one of the primary rhubarb species used for food and medicinal purposes, and it has recently been gaining more attention and recognition. This research represents the first attempt to use stable isotopes and elemental analysis via IRMS to identify the [...] Read more.
Rheum tanguticum is one of the primary rhubarb species used for food and medicinal purposes, and it has recently been gaining more attention and recognition. This research represents the first attempt to use stable isotopes and elemental analysis via IRMS to identify the geographical origin of Rheum tanguticum. A grand total of 190 rhubarb samples were gathered from 38 locations spread throughout the provinces of Gansu, Sichuan, and Qinghai in China. The carbon content showed a decreasing trend in the order of Qinghai, followed by Sichuan, and then Gansu. Nitrogen content was notably higher, with Qinghai and Sichuan displaying similar levels, while Gansu had the lowest nitrogen levels. Significant differences were noted in the δ13C (−28.9 to −26.5‰), δ15N (2.6 to 5.6‰), δ2H (−120.0 to −89.3‰), and δ18O (16.0‰ to 18.8‰) isotopes among the various rhubarb cultivation areas. A significant negative correlation was found between %C and both longitude and humidity. Additionally, δ13C and δ15N isotopes were negatively correlated with longitude, and δ15N showed a negative correlation with humidity as well. δ2H and δ18O isotopes exhibited a strong positive correlation with latitude, while significant negative correlations were observed between δ2H and δ18O isotopes and temperature, precipitation, and humidity. The LDA, PLS-DA, and k-NN models all exhibited strong classification performance in both the training and validation sets, achieving accuracy rates between 82.1% and 91.7%. The combination of stable isotopes, elemental analysis, and chemometrics provides a reliable and efficient discriminant model for accurately determining the geographical origin of R. tanguticum in different regions. In the future, the approach will aid in identifying the geographical origin and efficacy of rhubarb in other studies. Full article
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Figure 1
<p>Geographical location of rhubarb samples from different geographical regions in China.</p>
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<p>Box and whisker diagram of carbon (<span class="html-italic">δ</span><sup>13</sup>C), nitrogen (<span class="html-italic">δ</span><sup>15</sup>N), hydrogen (<span class="html-italic">δ</span><sup>2</sup>H), and oxygen (<span class="html-italic">δ</span><sup>18</sup>O) isotope compositions and nitrogen (N) and carbon (C) elemental contents of rhubarb in the different geographical regions. The box represents the 25 to 75 percentage, and the center line is the median line. The whiskers represent the range, the black rhombus “♦” is the outlier value, and the white circles “○” represent the mean value. a–c letters represent significant differences.</p>
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<p>Correlation plots of stable isotope values and environmental factors.</p>
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<p>(<b>a</b>) Plot of the first two discriminant functions obtained with LDA. (<b>b</b>) PLS-DA modeling results based on stable isotopes for the geographical origin of <span class="html-italic">R. tanguticum</span> in different regions. (<b>c</b>) the variance importance plot (VIP).</p>
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17 pages, 6828 KiB  
Article
Untargeted Metabolomics Approach for the Discovery of Salinity-Related Alkaloids in a Stony Coral-Derived Fungus Aspergillus terreus
by Yayue Liu, Li Wang, Yunkai Feng, Qingnan Liao, Xiaoling Lei, Xueqiong Hu, Longjian Zhou and Yi Zhang
Int. J. Mol. Sci. 2024, 25(19), 10544; https://doi.org/10.3390/ijms251910544 - 30 Sep 2024
Viewed by 271
Abstract
As a part of the important species that form coral reef ecosystems, stony corals have become a potential source of pharmacologically active lead compounds for an increasing number of compounds with novel chemical structures and strong biological activity. In this study, the secondary [...] Read more.
As a part of the important species that form coral reef ecosystems, stony corals have become a potential source of pharmacologically active lead compounds for an increasing number of compounds with novel chemical structures and strong biological activity. In this study, the secondary metabolites and biological activities are reported for Aspergillus terreus C21-1, an epiphytic fungus acquired from Porites pukoensis collected from Xuwen Coral Reef Nature Reserve, China. This strain was cultured in potato dextrose broth (PDB) media and rice media with different salinities based on the OSMAC strategy. The mycelial morphology and high-performance thin layer chromatographic (HPTLC) fingerprints of the fermentation extracts together with bioautography were recorded. Furthermore, an untargeted metabolomics study was performed using principal component analysis (PCA), orthogonal projection to latent structure discriminant analysis (O-PLSDA), and feature-based molecular networking (FBMN) to analyze their secondary metabolite variations. The comprehensive results revealed that the metabolite expression in A. terreus C21-1 differed significantly between liquid and solid media. The metabolites produced in liquid medium were more diverse but less numerous compared to those in solid medium. Meanwhile, the mycelial morphology underwent significant changes with increasing salinity under PDB cultivation conditions, especially in PDB with 10% salinity. Untargeted metabolomics revealed significant differences between PDB with 10% salinity and other media, as well as between liquid and solid media. FBMN analysis indicated that alkaloids, which might be produced under high salt stress, contributed largely to the differences. The biological activities results showed that six groups of crude extracts exhibited acetylcholinesterase (AChE) inhibitory activities, along with 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and antibacterial activities. The results of this study showed that the increase in salinity favored the production of unique alkaloid compounds by A. terreus C21-1. Full article
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<p>The morphological characteristics of <span class="html-italic">Aspergillus terreus</span> C21-1 in different media over a period of 28 days (G1–G6); 1 means the front and 2 the back of the plate.</p>
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<p>HPTLC fingerprints of six crude extracts are presented in the following figures. (<b>A</b>) shows the UV images of experiments G1–G6 under 254 nm, with sample numbers marked below the starting line. (<b>B</b>) displays the UV images of G1–G6 under 365 nm. The unfolding system used was <span class="html-italic">n</span>-hexane: ethyl acetate = 3:2 (<span class="html-italic">v</span>/<span class="html-italic">v</span>). The rulers beside the TLC plate were utilized as references for calculating the Rf values.</p>
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<p>The HPLC fingerprints of the six crude extracts using a UV wave length of 210 nm.</p>
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<p>PCA analysis of all groups of the <span class="html-italic">A. terreus</span> C21-1.</p>
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<p>(<b>A</b>) OPLS-DA plot (R2X: 0.730, R2Y:0.916, Q2: 0.884) of liquid medium and solid medium groups of the <span class="html-italic">A. terreus</span> C21-1 metabolic profiles. (<b>B</b>) OPLS−DA s−plot for liquid medium vs. solid medium groups. Dots represent individual metabolites; dots highlighted in light orange correspond to metabolites with a VIP value greater than 3.</p>
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<p>(<b>A</b>) OPLS−DA plot (R2X: 0.983, R2Y:1.000, Q2: 0.999) of 0.3% salinity and 10% salinity groups. (<b>B</b>) OPLS−DA s−plot for 0.3% salinity vs. 10% salinity groups. Dots represent individual metabolites; dots highlighted in light orange correspond to metabolites with a VIP value greater than 3.</p>
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<p>The metabolic profile of the features in extracts 0.3 PDB (<b>A</b>) and 10 PDB (<b>B</b>) showing their retention times, precursor ion <span class="html-italic">m</span>/<span class="html-italic">z</span> values, and intensities (exported from MSDIAL).</p>
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<p>The statistics of the numbers of the total features (<b>A</b>), the annotated and unknown features (<b>B</b>), and the alkaloids (<b>C</b>) detected in the two crude extracts.</p>
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<p>The FBMN molecular network based on positive ion MS/MS spectral similarity, showing a selection of amplified clusters. In the FBMN network, each node represents a feature marked with the mean <span class="html-italic">m</span>/<span class="html-italic">z</span> value of the parent ion, and the similarity of the secondary mass spectra between compounds was expressed by the cosine value, which was proportional to the similarity. The different colors of sections in the nodes represent different samples, i.e.,: <span class="html-fig-inline" id="ijms-25-10544-i001"><img alt="Ijms 25 10544 i001" src="/ijms/ijms-25-10544/article_deploy/html/images/ijms-25-10544-i001.png"/></span> respectively, 0.3 PDB and 10 PDB. The thickness of the connecting lines between nodes is positively correlated with the cosine value. The node size reflects the feature abundance (ion intensity). The A, B, C, D, E represent a locally enlarged view of a, b, c, d, e, respectively.</p>
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18 pages, 5510 KiB  
Article
Classification of Mass Spectral Data to Assist in the Identification of Novel Synthetic Cannabinoids
by Kristopher C. Evans-Newman, Garion L. Schneider and Nuwan T. Perera
Molecules 2024, 29(19), 4646; https://doi.org/10.3390/molecules29194646 - 30 Sep 2024
Viewed by 268
Abstract
Detection and characterization of newly synthesized cannabinoids (NSCs) is challenging due to the lack of availability of reference standards and chemical data. In this study, a binary classification system was developed and validated using partial least square discriminant analysis (PLS-DA) by utilizing readily [...] Read more.
Detection and characterization of newly synthesized cannabinoids (NSCs) is challenging due to the lack of availability of reference standards and chemical data. In this study, a binary classification system was developed and validated using partial least square discriminant analysis (PLS-DA) by utilizing readily available mass spectral data of known drugs to assist in the identification of previously unknown NCSs. First, a binary classification model was developed to discriminate cannabinoids and cannabinoid-related compounds from other drug classes. Then, a classification model was developed to discriminate classical (THC-related) from synthetic cannabinoids. Additional models were developed based on the most abundant functional groups including core groups such as indole, indazole, azaindole, and naphthoylpyrrole, as well as head and tail groups including 4-fluorobenzyl (FUB) and 5-Fluoropentyl (5-F). The predictive ability of these models was tested via both cross-validation and external validation. The results show that all models developed are highly accurate. Additionally, latent variables (LVs) of each model provide useful mass to charge (m/z) for discrimination between classes, which further facilitates the identification of different functional groups of previously unknown drug molecules. Full article
(This article belongs to the Section Analytical Chemistry)
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<p>Structure of JWH-018 demonstrating the major groups of a typical synthetic cannabinoid.</p>
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<p>PCA score plot of cannabinoids (Red) and other drug classes (Green).</p>
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<p>General overview of the binary classification system.</p>
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<p>The Results of PLS-DA analysis of cannabinoids and other drugs using GA as a feature selection method: (<b>a</b>) PLS-DA score plot of the training set; (<b>b</b>) PLS-DA score plot of the prediction set; (<b>c</b>) LV1 with the weights. Here, the x-axis is the <span class="html-italic">m</span>/<span class="html-italic">z</span> ratio.</p>
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<p>The Results of PLS-DA analysis of synthetic cannabinoids and classical cannabinoids: (<b>a</b>) score plot of the training set and (<b>b</b>) prediction set without using variable selection methods; (<b>c</b>) score plot of the training set and (<b>d</b>) prediction set with using GA as the variable selection method. (<b>e</b>) LV1 of the weights for the model developed using GA as the variable selection method.</p>
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<p>Functional groups of primary interest in the current study.</p>
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<p>Dendrogram showing the results of HCA. Green: mostly classical cannabinoids, Red: mostly naphthyl head group containing cannabinoids, Blue: mostly indole core containing cannabinoids, and Yellow: mostly azaindole/indazole core containing cannabinoids.</p>
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<p>Formation of fragments of interest for indole and indazole core groups: (<b>a</b>) Indole core group with pentyl tail group. (<b>b</b>) Indazole core group with pentyl tail group. (<b>c</b>) Indole core group with 5-fluoropentyl tail group. (<b>d</b>) Indazole core group with 5-fluoropentyl tail group.</p>
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<p>Formation of fragments of interest for cannabinoids containing naphthyl head group: (<b>a</b>) with indole, (<b>b</b>) with indazole core groups.</p>
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<p>Formation of fragments of interest for cannabinoids containing FUB tail group.</p>
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<p>Formation of fragments of interest for cannabinoids containing 5-fluoropentyl tail group: (<b>a</b>) with indole, (<b>b</b>) with indazole core groups.</p>
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18 pages, 2132 KiB  
Article
TLR4 as a Potential Target of Me-PFOSA-AcOH Leading to Cardiovascular Diseases: Evidence from NHANES 2013–2018 and Molecular Docking
by Zhilei Mao, Yanling Chen, Haixin Li, Qun Lu and Kun Zhou
Toxics 2024, 12(10), 693; https://doi.org/10.3390/toxics12100693 - 25 Sep 2024
Viewed by 457
Abstract
Background: Concerns have been raised regarding the effects of perfluoroalkyl substance (PFAS) exposure on cardiovascular diseases (CVD), but clear evidence linking PFAS exposure to CVD is lacking, and the mechanism remains unclear. Objectives: To study the association between PFASs and CVD in U.S. [...] Read more.
Background: Concerns have been raised regarding the effects of perfluoroalkyl substance (PFAS) exposure on cardiovascular diseases (CVD), but clear evidence linking PFAS exposure to CVD is lacking, and the mechanism remains unclear. Objectives: To study the association between PFASs and CVD in U.S. population, and to reveal the mechanism of PFASs’ effects on CVD. Methods: To assess the relationships between individual blood serum PFAS levels and the risk of total CVD or its subtypes, multivariable logistic regression analysis and partial least squares discriminant analysis (PLS-DA) were conducted on all participants or subgroups among 3391 adults from the National Health and Nutrition Examination Survey (NHANES). The SuperPred and GeneCards databases were utilized to identify potential targets related to PFAS and CVD, respectively. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of intersection genes were performed using Metascape. Protein interaction networks were generated, and core targets were identified with STRING. Molecular docking was achieved using Autodock Vina 1.1.2. Results: There was a positive association between Me-PFOSA-AcOH and CVD (OR = 1.28, p = 0.022), especially coronary heart disease (CHD) (OR = 1.47, p = 0.007) and heart attack (OR = 1.58, p < 0.001) after adjusting for all potential covariates. Me-PFOSA-AcOH contributed the most to distinguishing between individuals in terms of CVD and non-CVD. Significant moderating effects for Me-PFOSA-AcOH were observed in the subgroup analysis stratified by sex, ethnicity, education level, PIR, BMI, smoking status, physical activity, and hypertension (p < 0.05). The potential intersection targets were mainly enriched in CVD-related pathways, including the inflammatory response, neuroactive ligand–receptor interaction, MAPK signaling pathway, and arachidonic acid metabolism. TLR4 was identified as the core target for the effects of Me-PFOSA-AcOH on CVD. Molecular docking results revealed that the binding energy of Me-PFOSA-AcOH to the TLR4-MD-2 complex was −7.2 kcal/mol, suggesting that Me-PFOSA-AcOH binds well to the TLR4-MD-2 complex. Conclusions: Me-PFOSA-AcOH exposure was significantly associated with CVD. Network toxicology and molecular docking uncovered novel molecular targets, such as TLR4, and identified the inflammatory and metabolic mechanisms underlying Me-PFOSA-AcOH-induced CVD. Full article
(This article belongs to the Section Human Toxicology and Epidemiology)
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<p>VIP plot of the PLS-DA model for (<b>A</b>) the total CVD; (<b>B</b>) angina pectoris; (<b>C</b>) congestive heart failure; (<b>D</b>) coronary heart disease; (<b>E</b>) heart attack and (<b>F</b>) stroke.</p>
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<p>Subgroup analysis for the relationship between Me-PFOSA-AcOH and CVD, adjusted for sex, age, ethnicity, education level, PIR, physical activity, smoking status, drinking status, family history of CVD, BMI, and hypertension, with the exception of the subgroup variable.</p>
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<p>Me-PFOSA-AcOH acts on relevant targets in CVD: PPI network and bar plots of enrichment analysis. (<b>A</b>) Venn diagram indicating the intersecting genes for Me-PFOSA-AcOH and CVD. (<b>B</b>) PPI networks highlight the core targets for the action of Me-PFOSA-AcOH on CVD. Red circle indicated targets with degree value &gt; 4 by Cytoscape 3.10.2 software. (<b>C</b>–<b>E</b>) GO functional enrichment analysis. (<b>F</b>) KEGG pathway enrichment analysis.</p>
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<p>The molecular docking data of Me-PFOSA-AcOH on TLR4-MD-2 complex were analyzed using Autodock Vina 1.1.2.</p>
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<p>Selection of study participants.</p>
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18 pages, 5324 KiB  
Article
Comparison between Traditional and Novel NMR Methods for the Analysis of Sicilian Monovarietal Extra Virgin Olive Oils: Metabolic Profile Is Influenced by Micro-Pedoclimatic Zones
by Archimede Rotondo, Giovanni Bartolomeo, Irene Maria Spanò, Giovanna Loredana La Torre, Giuseppe Pellicane, Maria Giovanna Molinu and Nicola Culeddu
Molecules 2024, 29(19), 4532; https://doi.org/10.3390/molecules29194532 - 24 Sep 2024
Viewed by 345
Abstract
Nuclear magnetic resonance (NMR) metabolomic analysis was applied to investigate the differences within nineteen Sicilian Nocellara del Belice monovarietal extra virgin olive oils (EVOOs), grown in two zones that are different in altitude and soil composition. Several classes of endogenous olive oil metabolites [...] Read more.
Nuclear magnetic resonance (NMR) metabolomic analysis was applied to investigate the differences within nineteen Sicilian Nocellara del Belice monovarietal extra virgin olive oils (EVOOs), grown in two zones that are different in altitude and soil composition. Several classes of endogenous olive oil metabolites were quantified through a nuclear magnetic resonance (NMR) three-experiment protocol coupled with a yet-developed data-processing called MARA-NMR (Multiple Assignment Recovered Analysis by Nuclear Magnetic Resonance). This method, taking around one-hour of experimental time per sample, faces the possible quantification of different class of compounds at different concentration ranges, which would require at least three alternative traditional methods. NMR results were compared with the data of traditional analytical methods to quantify free fatty acidity (FFA), fatty acid methyl esters (FAMEs), and total phenol content. The presented NMR methodology is compared with traditional analytical practices, and its consistency is also tested through slightly different data treatment. Despite the rich literature about the NMR of EVOOs, the paper points out that there are still several advances potentially improving this general analysis and overcoming the other cumbersome and multi-device analytical strategies. Monovarietal EVOO’s composition is mainly affected by pedoclimatic conditions, in turn relying upon the nutritional properties, quality, and authenticity. Data collection, analysis, and statistical processing are discussed, touching on the important issues related to the climate changes in Sicily and to the specific influence of pedoclimatic conditions. Full article
(This article belongs to the Special Issue New Insights into Nuclear Magnetic Resonance (NMR) Spectroscopy)
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<p>Histograms representing the compared quantification of the fatty acids/esters by NMR and GC processing in % of the molecular fraction: (<b>a</b>) TUFA, which is linolenic acid/esters (Ln); (<b>b</b>) DUFA linoleic acid/esters (L); (<b>c</b>) Total mono-unsaturated fatty esters (MUFA, which is O + V + PO); (<b>d</b>) Saturated fatty acid esters (SFA, which is mostly P + S and other minor fatty acids).</p>
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<p>Comparison by histograms of the total phenolic content measured by NMR and through the traditional spectrophotometric Folin–Ciocâlteu method.</p>
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<p>Statistical graphs concerning the multi-variate analyses: (<b>a</b>) PCA biplot showing two score groups (in red and blue) and loadings (green spots) R<sup>2</sup> 0.606 Q<sup>2</sup> 0.176; (<b>b</b>) PLS-DA score plot showing two L1 and L2 groups with R<sup>2</sup> 0.889 and Q<sup>2</sup> 0.789; (<b>c</b>) PLS-DA biplot; (<b>d</b>) 60-fold permutation.</p>
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<p>Score contribution that summarizes the importance of the X-variables for both the X- and Y-models.</p>
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<p>Maps reporting the main differences between sampling zones (<b>a</b>) Topography (<b>b</b>) Soil description and associations. Data were obtained from Sit-AGRO (Sicily Region- Sistema Informativo Territoriale—<a href="https://www.sitagro.it/jml/" target="_blank">https://www.sitagro.it/jml/</a>, accessed on 1 May 202).</p>
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<p>Stack plot of the 1H-NMR experiments. The main assignments of triglycerides and squalene are also evidenced.</p>
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<p><sup>1</sup>H selected NMR experiment (selected pulse in the 8.5–10.5 region). The main assignments of the five phenolic species are reported.</p>
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<p>Stack plot of the 13C{1H} NMR experiments. Some detailed regions are evidenced, with the specific assignment employed to infer the relative quantifications.</p>
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<p>Overlapped DPFGSE-<sup>1</sup>H NMR experiments (from sample S_1) with or without a small amount of DMSO. The profile clearly shows that secoiridoids do change their chemical nature even in the small presence of polar solvents, leading to water-like impurities. This is extensively published elsewhere.</p>
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19 pages, 2715 KiB  
Article
Hops across Continents: Exploring How Terroir Transforms the Aromatic Profiles of Five Hop (Humulus lupulus) Varieties Grown in Their Countries of Origin and in Brazil
by Marcos Edgar Herkenhoff, Oliver Brödel and Marcus Frohme
Plants 2024, 13(19), 2675; https://doi.org/10.3390/plants13192675 - 24 Sep 2024
Viewed by 420
Abstract
Humulus lupulus, or hops, is a vital ingredient in brewing, contributing bitterness, flavor, and aroma. The female plants produce strobiles rich in essential oils and acids, along with bioactive compounds like polyphenols, humulene, and myrcene, which offer health benefits. This study examined [...] Read more.
Humulus lupulus, or hops, is a vital ingredient in brewing, contributing bitterness, flavor, and aroma. The female plants produce strobiles rich in essential oils and acids, along with bioactive compounds like polyphenols, humulene, and myrcene, which offer health benefits. This study examined the aromatic profiles of five hop varieties grown in Brazil versus their countries of origin. Fifty grams of pelletized hops from each strain were collected and analyzed using HS-SPME/GC-MS to identify volatile compounds, followed by statistical analysis with PLS-DA and ANOVA. The study identified 330 volatile compounds and found significant aromatic differences among hops from different regions. For instance, H. Mittelfrüher grown in Brazil has a fruity and herbaceous profile, while the German-grown variety is more herbal and spicy. Similar variations were noted in the Magnum, Nugget, Saaz, and Sorachi Ace varieties. The findings underscore the impact of terroir on hop aromatic profiles, with Brazilian-grown hops displaying distinct profiles compared to their counterparts from their countries of origin, including variations in aromatic notes and α-acid content. Full article
(This article belongs to the Special Issue Plants as Food and Medicine)
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<p>Chemical interpretation of the PLS-DA model discriminating between hops planted in their countries of origin (red) and the same varieties planted in Brazil (blue). Samples are based on VIP scores and regression coefficients. The selected hop varieties were (<b>A</b>) Hallertauer Mittelfrüh, (<b>B</b>) Magnum, (<b>C</b>) Nugget, (<b>D</b>) Saaz, and (<b>E</b>) Sorachi Ace. The chromatogram regions significantly contribute to the PLS-DA model.</p>
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<p>Chemical interpretation of the PLS-DA model discriminating between hops planted in their countries of origin (red) and the same varieties planted in Brazil (blue). Samples are based on VIP scores and regression coefficients. The selected hop varieties were (<b>A</b>) Hallertauer Mittelfrüh, (<b>B</b>) Magnum, (<b>C</b>) Nugget, (<b>D</b>) Saaz, and (<b>E</b>) Sorachi Ace. The chromatogram regions significantly contribute to the PLS-DA model.</p>
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<p>Aromatic profiles according to the hop (<span class="html-italic">Humulus lupulus</span>) strain producers for the varieties used in this study grown in their countries of origin (DE: Germany; USA: United States; and CZ: Czech Republic) and grown in Brazil (BR).</p>
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13 pages, 2563 KiB  
Article
Non-Targeted Metabolomics of Serum Reveals Biomarkers Associated with Body Weight in Wumeng Black-Bone Chickens
by Zhong Wang, Xuan Yu, Shenghong Yang, Mingming Zhao and Liqi Wang
Animals 2024, 14(18), 2743; https://doi.org/10.3390/ani14182743 - 23 Sep 2024
Viewed by 359
Abstract
Growth performance is an important economic trait of broilers but the related serum metabolomics remains unclear. In this study, we utilized non-targeted metabolomics using ultra-high-performance liquid phase tandem mass spectrometry (UHPLC-MS/MS) to establish metabolite profiling in the serum of Chinese Wumeng black-bone chickens. [...] Read more.
Growth performance is an important economic trait of broilers but the related serum metabolomics remains unclear. In this study, we utilized non-targeted metabolomics using ultra-high-performance liquid phase tandem mass spectrometry (UHPLC-MS/MS) to establish metabolite profiling in the serum of Chinese Wumeng black-bone chickens. The biomarker metabolites in serum associated with growth performance of chickens were identified by comparing the serum metabolome differences between chickens that significantly differed in their weights at 160 days of age when fed identical diets. A total of 766 metabolites were identified including 13 differential metabolite classes such as lipids and lipid-like molecules, organic acids and their derivatives, and organoheterocyclic compounds. The results of difference analysis using a partial least squares discriminant analysis (PLS-DA) model indicated that the low-body-weight group could be differentiated based on inflammatory markers including prostaglandin a2, kynurenic acid and fatty acid esters of hydroxy fatty acids (FAHFA), and inflammation-related metabolic pathways including tryptophan and arachidonic acid metabolism. In contrast, the sera of high-body-weight chickens were enriched for riboflavin and 2-isopropylmalic acid and for metabolic pathways including riboflavin metabolism, acetyl group transfer into mitochondria, and the tricarboxylic acid (TCA) cycle. These results provide new insights into the practical application of improving the growth performance of local chickens. Full article
(This article belongs to the Special Issue Metabolic Disorders of Poultry)
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<p>Body weights of chickens in the high- and low-body-weight groups. (<b>A</b>) Body weight of chickens at 160 days of age. (<b>B</b>) Comparison of body weight between the WH/WL groups. WH: high-body-weight group, <span class="html-italic">n</span> = 16; WL: low-body-weight group, <span class="html-italic">n</span> = 16.</p>
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<p>Metabolite types in the serum metabolome of Wumeng black-bone chickens. A total of 13 types of metabolites and some unclassified metabolites were identified. The number above the column is the number of metabolites of each type. The pie chart at the top right illustrates the proportion of metabolites in each superclass.</p>
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<p>Analysis of serum metabolome of chickens in the WH and WL groups. PLS-DA analysis of non-targeted serum metabolites of chickens in the WH (<span class="html-italic">n</span> = 16) and WL (<span class="html-italic">n</span> = 16) group in (<b>A</b>) positive and (<b>B</b>) negative ion modes. Differential serum metabolites between the WH and WL groups and their VIP scores in (<b>C</b>) positive and (<b>D</b>) negative ion modes.</p>
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<p>Enrichment analysis of metabolic pathways of serum differential metabolites in high- and low-body-weight groups. (<b>A</b>) High-body-weight group; (<b>B</b>) low-body-weight group.</p>
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16 pages, 2369 KiB  
Article
A Novel Technique Using Confocal Raman Spectroscopy Coupled with PLS-DA to Identify the Types of Sugar in Three Tropical Fruits
by César R. Balcázar-Zumaeta, Jorge L. Maicelo-Quintana, Geidy Salón-Llanos, Miguel Barrena, Lucas D. Muñoz-Astecker, Ilse S. Cayo-Colca, Llisela Torrejón-Valqui and Efraín M. Castro-Alayo
Appl. Sci. 2024, 14(18), 8476; https://doi.org/10.3390/app14188476 - 20 Sep 2024
Viewed by 850
Abstract
Tropical fruits such as cherimoya, soursop, and pineapple share sugars (glucose, fructose, and sucrose) in common but may differ in the content of other phytochemicals. In the present work, confocal Raman spectroscopy and partial least squares discriminant analysis (PLS-DA) were used to establish [...] Read more.
Tropical fruits such as cherimoya, soursop, and pineapple share sugars (glucose, fructose, and sucrose) in common but may differ in the content of other phytochemicals. In the present work, confocal Raman spectroscopy and partial least squares discriminant analysis (PLS-DA) were used to establish a classification model among the three fruits and to evaluate the effect of pre-processing methods on the model’s performance. The Raman spectra showed that glucose was present in the fruits in the 800–900 cm−1 band and the 1100–1200 cm−1 band. While sucrose was present in the bands of 1131.22 cm−1, 1134.44 cm−1, and 1133.37 cm−1 in the three fruits, fructose was present in the bands of 1464.22 cm−1, 1467.44 cm−1, and 1464.22 cm−1 in cherimoya, soursop, and pineapple. The accuracy of the PLS-DA model varied according to the pre-processing methods used. The Savitzky–Golay first derivative method produced a model with 98.69–100% and 100% precision on the training and prediction data, respectively. Full article
(This article belongs to the Section Food Science and Technology)
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<p>Raman spectra of glucose, fructose, and sucrose in cherimoya, soursop, and pineapple.</p>
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<p>Chemometric analysis of raw (<b>a</b>) and corrected (<b>b</b>) Raman spectra of cherimoya, soursop, and pineapple.</p>
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<p>Chemometric analysis of raw (<b>a</b>) and corrected (<b>b</b>) Raman spectra of cherimoya, soursop, and pineapple.</p>
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<p>Spectrum pre-processed with (<b>a</b>) mean centering, (<b>b</b>) the first derivative of the Savitzky–Golay method, (<b>c</b>) the second derivative of the Savitzky–Golay method, and (<b>d</b>) the third derivative of the Savitzky–Golay method.</p>
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<p>Q vs Hotelling’s T<sup>2</sup> in the PCA model. Both parameters are below 95%. Pre-processing methods: (<b>a</b>) mean centering method, (<b>b</b>) first derivative of the Savitzky–Golay method, (<b>c</b>) second derivative of the Savitzky–Golay method, and (<b>d</b>) third derivative of the Savitzky–Golay method.</p>
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<p>PCA scores and loadings with different pre-processing methods: (<b>a</b>,<b>b</b>) mean centering, (<b>c</b>,<b>d</b>) first derivative of Savitzky–Golay, (<b>e</b>,<b>f</b>) second derivative of Savitzky–Golay, and (<b>g</b>,<b>h</b>) third derivative of Savitzky–Golay method.</p>
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<p>PCA scores and loadings with different pre-processing methods: (<b>a</b>,<b>b</b>) mean centering, (<b>c</b>,<b>d</b>) first derivative of Savitzky–Golay, (<b>e</b>,<b>f</b>) second derivative of Savitzky–Golay, and (<b>g</b>,<b>h</b>) third derivative of Savitzky–Golay method.</p>
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<p>ROC curves for the first derivative of the Savitzky–Golay pre-processing method.</p>
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20 pages, 8866 KiB  
Article
Identification and Analysis of the Superoxide Dismutase (SOD) Gene Family and Potential Roles in High-Temperature Stress Response of Herbaceous Peony (Paeonia lactiflora Pall.)
by Xiaoxuan Chen, Danqing Li, Junhong Guo, Qiyao Wang, Kaijing Zhang, Xiaobin Wang, Lingmei Shao, Cheng Luo, Yiping Xia and Jiaping Zhang
Antioxidants 2024, 13(9), 1128; https://doi.org/10.3390/antiox13091128 - 18 Sep 2024
Viewed by 590
Abstract
The herbaceous peony (Paeonia lactiflora Pall.) plant is world-renowned for its ornamental, medicinal, edible, and oil values. As global warming intensifies, its growth and development are often affected by high-temperature stress, especially in low-latitude regions. Superoxide dismutase (SOD) is an important enzyme [...] Read more.
The herbaceous peony (Paeonia lactiflora Pall.) plant is world-renowned for its ornamental, medicinal, edible, and oil values. As global warming intensifies, its growth and development are often affected by high-temperature stress, especially in low-latitude regions. Superoxide dismutase (SOD) is an important enzyme in the plant antioxidant systems and plays vital roles in stress response by maintaining the dynamic balance of reactive oxygen species (ROS) concentrations. To reveal the members of then SOD gene family and their potential roles under high-temperature stress, we performed a comprehensive identification of the SOD gene family in the low-latitude cultivar ‘Hang Baishao’ and analyzed the expression patterns of SOD family genes (PlSODs) in response to high-temperature stress and exogenous hormones. The present study identified ten potential PlSOD genes, encoding 145–261 amino acids, and their molecular weights varied from 15.319 to 29.973 kDa. Phylogenetic analysis indicated that PlSOD genes were categorized into three sub-families, and members within each sub-family exhibited similar conserved motifs. Gene expression analysis suggested that SOD genes were highly expressed in leaves, stems, and dormancy buds. Moreover, RNA-seq data revealed that PlCSD1-1, PlCSD3, and PlFSD1 may be related to high-temperature stress response. Finally, based on the Quantitative Real-time PCR (qRT-PCR) results, seven SOD genes were significantly upregulated in response to high-temperature stress, and exogenous EBR and ABA treatments can enhance high-temperature tolerance in P. lactiflora. Overall, these discoveries lay the foundation for elucidating the function of PlSOD genes for the thermotolerance of herbaceous peony and facilitating the genetic breeding of herbaceous peony cultivars with strong high-temperature resistance. Full article
(This article belongs to the Section Antioxidant Enzyme Systems)
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<p>Phylogenetic tree of SOD proteins in <span class="html-italic">P. lactiflora</span>, <span class="html-italic">A. thaliana</span>, <span class="html-italic">S. lycopersicum</span>, <span class="html-italic">V. vinifera</span>, <span class="html-italic">Z. mays</span>, and <span class="html-italic">G. max</span> constructed using the neighbor-joining method. The tree was clustered into three major groups (Cu/Zn-SODs, Fe-SODs, and Mn-SODs), denoted by different colors. The proteins of herbaceous peony are marked in red and the SODs from different species were distinguished with different colors and shapes.</p>
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<p>Multiple alignment of PlSOD proteins of functional domains. (<b>A</b>) Cu/Zn-SODs sub-family sequence alignment. (<b>B</b>) Fe-SODs and Mn-SODs sub-family sequence alignment. The SOD domains Sod_Cu, Sod_Fe_N, and Sod_Fe_C are marked in red boxes. The black, red, and blue parts represent homology equal to 100%, greater than 75%, and greater than 50%, respectively.</p>
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<p>Phylogenetic tree, conserved motifs, and domain analysis of <span class="html-italic">PlSOD</span> genes. (<b>A</b>) Phylogenetic tree of <span class="html-italic">PlSOD</span> genes. (<b>B</b>) Conserved structure domains of PlSOD proteins. (<b>C</b>) Nine conserved motifs of PlSOD proteins marked by different colors. The green, yellow, and pink rectangles indicate the SOD_Cu structural domain (PF00080), SOD_Fe_N structural domain (PF00081), and SOD_Fe_C structural domain (PF02777), respectively. (<b>D</b>) Amino acids sequence of the motifs. The letter size indicates the degree of conservation in the sequences.</p>
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<p>Expression analysis of <span class="html-italic">PlSOD</span> genes in different tissues. The expression data were obtained from qRT-PCR, and the comparisons were based on the expression levels at the flower bud. Statistically significant differences are indicated using asterisks (Duncan’s test, * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001). Data are presented as the means ± SD of three replicates.</p>
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<p>Expression profiles of <span class="html-italic">PlSOD</span> genes under natural high-temperature stress. (<b>A</b>) The phenotypes of herbaceous peony leaves subjected to high-temperature stress. (<b>B</b>) Expression profiles of <span class="html-italic">PlSOD</span> genes under high-temperature stress. The FPKM values of genes in samples were shown by different colored rectangles and the comparisons were based on the FPKM values on May 15th. Red indicates high expression. Statistically significant differences are indicated using asterisks (Duncan’s test, * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001). Data are presented as the means ± SD of three replicates.</p>
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<p>Phenotype, physiological indices, and Chl fluorescence of <span class="html-italic">P. lactiflora</span> plants treated with different hormones after high-temperature treatment for 48 h. (<b>A</b>) Phenotype of control group and hormone-treated group. (<b>B</b>) Chl fluorescence imaging screens. (<b>C</b>) SOD activity, MDA, and H<sub>2</sub>O<sub>2</sub> accumulation. (<b>D</b>) Chlorophyll fluorescence parameters. All data are the means of three replicates with standard deviations, and different letters indicate significant differences among the data according to Duncan’s multiple range test (<span class="html-italic">p</span> &lt; 0.05).</p>
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<p>Expression profiles of <span class="html-italic">PlSOD</span> genes in peony leaves treated with distilled water (<b>A</b>), exogenous EBR (<b>B</b>), ABA (<b>C</b>), and MeJA (<b>D</b>) under high-temperature stress. EBR: 2, 4-epibrassinolide; ABA: Abscisic acid; MeJA: Methyl jasmonate. The mean values were derived from three independent biological replicates. ANOVA was used to test significance. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001. Error bars represent the standard deviation.</p>
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18 pages, 3452 KiB  
Article
Differentiating Pond-Intensive, Paddy-Ecologically, and Free-Range Cultured Crayfish (Procambarus clarkii) Using Stable Isotope and Multi-Element Analysis Coupled with Chemometrics
by Zhenzhen Xia, Zhi Liu, Yan Liu, Wenwen Cui, Dan Zheng, Mingfang Tao, Youxiang Zhou and Xitian Peng
Foods 2024, 13(18), 2947; https://doi.org/10.3390/foods13182947 - 18 Sep 2024
Viewed by 400
Abstract
The farming pattern of crayfish significantly impacts their quality, safety, and nutrition. Typically, green and ecologically friendly products command higher economic value and market competitiveness. Consequently, intensive farming methods are frequently employed in an attempt to replace these environmentally friendly products, leading to [...] Read more.
The farming pattern of crayfish significantly impacts their quality, safety, and nutrition. Typically, green and ecologically friendly products command higher economic value and market competitiveness. Consequently, intensive farming methods are frequently employed in an attempt to replace these environmentally friendly products, leading to potential instances of commercial fraud. In this study, stable isotope and multi-element analysis were utilized in conjunction with multivariate modeling to differentiate between pond-intensive, paddy-ecologically, and free-range cultured crayfish. The four stable isotope ratios of carbon, nitrogen, hydrogen, and oxygen (δ13C, δ15N, δ2H, δ18O) and 20 elements from 88 crayfish samples and their feeds were determined for variance analysis and correlation analysis. To identify and differentiate three different farming pattern crayfish, unsupervised methods such as hierarchical cluster analysis (HCA) and principal component analysis (PCA) were used, as well as supervised multivariate modeling, specifically partial least squares discriminant analysis (PLS-DA). The HCA and PCA exhibited limited effectiveness in classifying the farming pattern of crayfish, whereas the PLS-DA demonstrated a more robust performance with a predictive accuracy of 90.8%. Additionally, variables such as δ13C, δ15N, δ2H, Mn, and Co exhibited relatively higher contributions in the PLS-DA model, with a variable influence on projection (VIP) greater than 1. This study is the first attempt to use stable isotope and multi-element analysis to distinguish crayfish under three farming patterns. It holds promising potential as an effective strategy for crayfish authentication. Full article
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<p>Map of crayfish sampling sites from different farming patterns in Hubei province. PC, RC, and WC represent pond crayfish, rice crayfish and wild crayfish, respectively.</p>
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<p>The ANOVA boxplots depict stable isotope ratios (δ<sup>13</sup>C, δ<sup>15</sup>N, δ<sup>2</sup>H, and δ<sup>18</sup>O) of crayfish from different farming patterns.</p>
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<p>Boxplots of δ<sup>13</sup>C (<b>A</b>) and δ<sup>15</sup>N (<b>B</b>) of crayfish from different farming patterns, environment samples (e.g., sediment, aquatic plants, and rice), and feed samples (e.g., commercial feed and soya bean); (<b>C</b>) radar plot of the mean values of 20 elemental contents in crayfish and feeds; (<b>D</b>) correlation heat map of crayfish and feeds.</p>
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<p>(<b>A</b>) Hierarchical clustering of different crayfish farming patterns and correlations of stable isotopic and multi-element data of crayfish with their farming patterns; (<b>B</b>) unsupervised PCA classification results of pond crayfish (PC), rice crayfish (RC), and wild crayfish (WC) scatter plots of the first two principal scores (PC1 and PC2) and corresponding variable loadings (<b>1</b>) only stable isotopic data used and (<b>2</b>) only multi-element data used; (<b>3</b>) both stable isotopic and multi-element data.</p>
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<p>PLS-DA model using 4 stable isotopes and 20 elements from crayfish to differentiate pond crayfish (PC), rice crayfish (RC), and wild crayfish (WC): (<b>A</b>) score plot of samples; (<b>B</b>) loading plot of variables, with X standing for 24 variables and Y standing for three farming patterns; (<b>C</b>) VIP plot of variables.</p>
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<p>PLS-DA model using 4 stable isotopes and 20 elements from crayfish to differentiate pond crayfish (PC), rice crayfish (RC), and wild crayfish (WC): (<b>A</b>) score plot of samples; (<b>B</b>) loading plot of variables, with X standing for 24 variables and Y standing for three farming patterns; (<b>C</b>) VIP plot of variables.</p>
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20 pages, 3457 KiB  
Article
Non-Invasive Endometrial Cancer Screening through Urinary Fluorescent Metabolome Profile Monitoring and Machine Learning Algorithms
by Monika Švecová, Katarína Dubayová, Anna Birková, Peter Urdzík and Mária Mareková
Cancers 2024, 16(18), 3155; https://doi.org/10.3390/cancers16183155 - 14 Sep 2024
Viewed by 545
Abstract
Endometrial cancer is becoming increasingly common, highlighting the need for improved diagnostic methods that are both effective and non-invasive. This study investigates the use of urinary fluorescence spectroscopy as a potential diagnostic tool for endometrial cancer. Urine samples were collected from endometrial cancer [...] Read more.
Endometrial cancer is becoming increasingly common, highlighting the need for improved diagnostic methods that are both effective and non-invasive. This study investigates the use of urinary fluorescence spectroscopy as a potential diagnostic tool for endometrial cancer. Urine samples were collected from endometrial cancer patients (n = 77), patients with benign uterine tumors (n = 23), and control gynecological patients attending regular checkups or follow-ups (n = 96). These samples were analyzed using synchronous fluorescence spectroscopy to measure the total fluorescent metabolome profile, and specific fluorescence ratios were created to differentiate between control, benign, and malignant samples. These spectral markers demonstrated potential clinical applicability with AUC as high as 80%. Partial Least Squares Discriminant Analysis (PLS-DA) was employed to reduce data dimensionality and enhance class separation. Additionally, machine learning models, including Random Forest (RF), Logistic Regression (LR), Support Vector Machine (SVM), and Stochastic Gradient Descent (SGD), were utilized to distinguish between controls and endometrial cancer patients. PLS-DA achieved an overall accuracy of 79% and an AUC of 90%. These promising results indicate that urinary fluorescence spectroscopy, combined with advanced machine learning models, has the potential to revolutionize endometrial cancer diagnostics, offering a rapid, accurate, and non-invasive alternative to current methods. Full article
(This article belongs to the Special Issue Image Analysis and Machine Learning in Cancers)
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<p>Semiquantitive strip analysis comparison of positive urine parameters.</p>
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<p>Urinary total fluorescent metabolome profiles (uTFMP) divided into fluorescent zones.</p>
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<p>Fluorescent urinary zones. Values are expressed as median ± interquartile range. **** indicates <span class="html-italic">p</span> &lt; 0.0001, *** indicates <span class="html-italic">p</span> &lt; 0.001, * <span class="html-italic">p</span> &lt; 0.05.</p>
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<p>Fluorescent ratios (<b>A</b>) Ratio Z4a/Z5. (<b>B</b>) Ratio Z6/Z7. Values are expressed as median ± interquartile range. **** indicates <span class="html-italic">p</span> &lt; 0.0001, *** indicates <span class="html-italic">p</span> &lt; 0.001, * <span class="html-italic">p</span> &lt; 0.05.</p>
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<p>Receiver operating characteristic curves (<b>A</b>) Ratio Z4a/Z5 (<b>B</b>) Ratio Z6/Z7.</p>
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<p>Partial Least Squares Discriminant Analysis (PLS-DA) (<b>A</b>) Train set between controls and malignant samples; (<b>B</b>) Test set between controls and malignant samples; (<b>C</b>) Train set between controls and benign samples; (<b>D</b>) Test set between controls and malignant samples; (<b>E</b>) ROC curve between controls and malignant samples; (<b>F</b>) ROC curve between controls and benign samples.</p>
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<p>ROC curves of built machine learning models (<b>A</b>) ML based on fluorescent zones and spectral ratios (<b>B</b>) ML based overall urinary total fluorescent metabolome profile.</p>
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<p>Confusion matrices for machine learning models: (<b>A</b>) fluorescent zones and spectral ratios. (<b>B</b>) overall urine total fluorescent metabolome profiles.</p>
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15 pages, 16898 KiB  
Article
A Comparison Analysis of Four Different Drying Treatments on the Volatile Organic Compounds of Gardenia Flowers
by Jiangli Peng, Wen Ai, Xinyi Yin, Dan Huang and Shunxiang Li
Molecules 2024, 29(18), 4300; https://doi.org/10.3390/molecules29184300 - 11 Sep 2024
Viewed by 342
Abstract
The gardenia flower not only has extremely high ornamental value but also is an important source of natural food and spices, with a wide range of uses. To support the development of gardenia flower products, this study used headspace gas chromatography–ion mobility spectrometry [...] Read more.
The gardenia flower not only has extremely high ornamental value but also is an important source of natural food and spices, with a wide range of uses. To support the development of gardenia flower products, this study used headspace gas chromatography–ion mobility spectrometry (HS-GC–IMS) technology to compare and analyze the volatile organic compounds (VOCs) of fresh gardenia flower and those after using four different drying methods (vacuum freeze-drying (VFD), microwave drying (MD), hot-air drying (HAD), and vacuum drying (VD)). The results show that, in terms of shape, the VFD sample is almost identical to fresh gardenia flower, while the HAD, MD, and VD samples show significant changes in appearance with clear wrinkling; a total of 59 volatile organic compounds were detected in the gardenia flower, including 13 terpenes, 18 aldehydes, 4 esters, 8 ketones, 15 alcohols, and 1 sulfide. Principal component analysis (PCA), cluster analysis (CA), and partial least-squares regression analysis (PLS-DA) were performed on the obtained data, and the research found that different drying methods impact the VOCs of the gardenia flower. VFD or MD may be the most effective alternative to traditional sun-drying methods. Considering its drying efficiency and production cost, MD has the widest market prospects. Full article
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<p>Photos of gardenia flowers (<b>A</b>) and powder (<b>B</b>) under different drying methods.</p>
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<p>The 3D spectrum of the volatile organic compounds (VOCs) of five groups of gardenia flowers.</p>
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<p>The 2D spectrum of the VOCs of five groups of gardenia flowers.</p>
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<p>Analysis of the spectral differences between the fresh group and the other four groups of gardenia flowers.</p>
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<p>Qualitative spectrum of VOCs in the five groups of gardenia flowers based on gas chromatography–ion mobility spectrometry (GC–IMS).</p>
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<p>Fingerprint of VOCs in the five groups of gardenia flowers.</p>
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<p>Principal component analysis (PCA) score plot of VOCs in the five groups of gardenia flower. (<b>a</b>) PCA score plot; (<b>b</b>) three-dimensional scatter plot.</p>
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<p>Cluster heatmap of VOCs in the five groups of gardenia flowers.</p>
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<p>PLS-DA analysis of VOCs in the five groups of gardenia flowers.</p>
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<p>VIP values of the characteristic variables.</p>
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<p>Permutation test results of VOCs in the five groups of gardenia flowers.</p>
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24 pages, 5237 KiB  
Article
Effect of the Bioprotective Properties of Lactic Acid Bacteria Strains on Quality and Safety of Feta Cheese Stored under Different Conditions
by Angeliki Doukaki, Olga S. Papadopoulou, Antonia Baraki, Marina Siapka, Ioannis Ntalakas, Ioannis Tzoumkas, Konstantinos Papadimitriou, Chrysoula Tassou, Panagiotis Skandamis, George-John Nychas and Nikos Chorianopoulos
Microorganisms 2024, 12(9), 1870; https://doi.org/10.3390/microorganisms12091870 - 10 Sep 2024
Viewed by 751
Abstract
Lately, the inclusion of additional lactic acid bacteria (LAB) strains to cheeses is becoming more popular since they can affect cheese’s nutritional, technological, and sensory properties, as well as increase the product’s safety. This work studied the effect of Lactiplantibacillus pentosus L33 and [...] Read more.
Lately, the inclusion of additional lactic acid bacteria (LAB) strains to cheeses is becoming more popular since they can affect cheese’s nutritional, technological, and sensory properties, as well as increase the product’s safety. This work studied the effect of Lactiplantibacillus pentosus L33 and Lactiplantibacillus plantarum L125 free cells and supernatants on feta cheese quality and Listeria monocytogenes fate. In addition, rapid and non-invasive techniques such as Fourier transform infrared (FTIR) and multispectral imaging (MSI) analysis were used to classify the cheese samples based on their sensory attributes. Slices of feta cheese were contaminated with 3 log CFU/g of L. monocytogenes, and then the cheese slices were sprayed with (i) free cells of the two strains of the lactic acid bacteria (LAB) in co-culture (F, ~5 log CFU/g), (ii) supernatant of the LAB co-culture (S) and control (C, UHT milk) or wrapped with Na-alginate edible films containing the pellet (cells, FF) or the supernatant (SF) of the LAB strains. Subsequently, samples were stored in air, in brine, or in vacuum at 4 and 10 °C. During storage, microbiological counts, pH, and water activity (aw) were monitored while sensory assessment was conducted. Also, in every sampling point, spectral data were acquired by means of FTIR and MSI techniques. Results showed that the initial microbial population of Feta was ca. 7.6 log CFU/g and consisted of LAB (>7 log CFU/g) and yeast molds in lower levels, while no Enterobacteriaceae were detected. During aerobic, brine, and vacuum storage for both temperatures, pathogen population was slightly postponed for S and F samples and reached lower levels compared to the C ones. The yeast mold population was slightly delayed in brine and vacuum packaging. For aerobic storage at 4 °C, an elongation in the shelf life of F samples by 4 days was observed compared to C and S samples. At 10 °C, the shelf life of both F and S samples was extended by 13 days compared to C samples. FTIR and MSI analyses provided reliable estimations of feta quality using the PLS-DA method, with total accuracy (%) ranging from 65.26 to 84.31 and 60.43 to 89.12, respectively. In conclusion, the application of bioprotective LAB strains can result in the extension of feta’s shelf life and provide a mild antimicrobial action against L. monocytogenes and spoilage microbiota. Furthermore, the findings of this study validate the effectiveness of FTIR and MSI techniques, in tandem with data analytics, for the rapid assessment of the quality of feta samples. Full article
(This article belongs to the Section Food Microbiology)
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<p>Population of the examined microorganisms and pH values in aerobic storage of non-inoculated feta cheese samples (mean values ± standard deviations) for (<b>a</b>): C samples stored at 4 °C, (<b>b</b>): F samples stored at 4 °C, (<b>c</b>): S samples stored at 4 °C, (<b>d</b>): C samples stored at 10 °C, (<b>e</b>): F samples stored at 10 °C, (<b>f</b>): S samples stored at 10 °C. (<b><span style="color:#3DF729">•</span></b>) Total viable counts, (<b><span style="color:#5B9BD5">•</span></b>) cocci/streptococci, (<b><span style="color:#ED7D31">•</span></b>) lactic acid bacteria, (<b><span style="color:#2F5496">•</span></b>) yeasts and molds are represented by a continuous line (-). pH values (<b><span style="color:#000000">•</span></b>) are indicated in the secondary axis and are represented with a dotted line (…). No statistically important differences were observed (<span class="html-italic">p</span> &gt; 0.05).</p>
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<p>Population of total viable counts (TVC) and <span class="html-italic">Listeria monocytogenes</span> in aerobic storage of inoculated feta cheese samples (mean values ± standard deviations) for (<b>a</b>): C samples stored at 4 °C, (<b>b</b>): F samples stored at 4 °C, (<b>c</b>): S samples stored at 4 °C, (<b>d</b>): C samples stored at 10 °C, (<b>e</b>): F samples stored at 10 °C, (<b>f</b>): S samples stored at 10 °C. (<b><span style="color:#3DF729">•</span></b>) TVC is represented by a continuous line (-), and <span class="html-italic">Listeria monocytogenes</span> (<b><span style="color:red">•</span></b>) is represented in dashed lines (---). No statistically important differences were observed (<span class="html-italic">p</span> &gt; 0.05).</p>
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<p>Population of the examined microorganisms and pH values in brine storage of non-inoculated Feta cheese samples (mean values ± standard deviations) for (<b>a</b>): C samples stored at 4 °C, (<b>b</b>): F samples stored at 4 °C, (<b>c</b>): S samples stored at 4 °C, (<b>d</b>): C samples stored at 10 °C, (<b>e</b>): F samples stored at 10 °C, (<b>f</b>): S samples stored at 10 °C. (<b><span style="color:#3DF729">•</span></b>) Total viable counts, (<b><span style="color:#5B9BD5">•</span></b>) cocci/streptococci, (<b><span style="color:#ED7D31">•</span></b>) lactic acid bacteria, (<b><span style="color:#2F5496">•</span></b>) yeasts and molds are represented by a continuous line (-). pH values (<b><span style="color:#000000">•</span></b>) are indicated in the secondary axis and are represented with a dotted line (…). No statistically important differences were observed (<span class="html-italic">p</span> &gt; 0.05), except from TVC between C and both F and S samples and cocci/streptococci at 10 °C between C and S samples.</p>
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<p>Population of total viable counts (TVC) and <span class="html-italic">Listeria monocytogenes</span> in brine storage of inoculated feta cheese samples (mean values ± standard deviations) for (<b>a</b>): C samples stored at 4 °C, (<b>b</b>): F samples stored at 4 °C, (<b>c</b>): S samples stored at 4 °C, (<b>d</b>): C samples stored at 10 °C, (<b>e</b>): F samples stored at 10 °C, (<b>f</b>): S samples stored at 10 °C. (<b><span style="color:#3DF729">•</span></b>) TVC is represented by a continuous line (-) and <span class="html-italic">Listeria monocytogenes</span> (<b><span style="color:red">•</span></b>) is represented in dashed lines (---). Statistically important differences (<span class="html-italic">p</span> &lt; 0.05) were observed for TVC between C and both F and S samples.</p>
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<p>Population of the examined microorganisms and pH values in vacuum storage of non-inoculated feta cheese samples (mean values ± standard deviations) for (<b>a</b>): C samples stored at 4 °C, (<b>b</b>): F samples stored at 4 °C, (<b>c</b>): S samples stored at 4 °C, (<b>d</b>): C samples stored at 10 °C, (<b>e</b>): F samples stored at 10 °C, (<b>f</b>): S samples stored at 10 °C. (<b><span style="color:#3DF729">•</span></b>) Total viable counts, (<b><span style="color:#5B9BD5">•</span></b>) cocci/streptococci, (<b><span style="color:#ED7D31">•</span></b>) lactic acid bacteria, (<b><span style="color:#2F5496">•</span></b>) yeasts and molds are represented by a continuous line (-). pH values (<b><span style="color:#000000">•</span></b>) are indicated in the secondary axis and are represented with a dotted line (…). No statistically important differences were observed (<span class="html-italic">p</span> &gt; 0.05) except from cocci/streptococci at 10 °C.</p>
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<p>Population of total viable counts (TVC) and <span class="html-italic">Listeria monocytogenes</span> in vacuum storage of inoculated feta cheese samples (mean values ± standard deviations) for (<b>a</b>): C samples stored at 4 °C, (<b>b</b>): F samples stored at 4 °C, (<b>c</b>): S samples stored at 4 °C, (<b>d</b>): C samples stored at 10 °C, (<b>e</b>): F samples stored at 10 °C, (<b>f</b>): S samples stored at 10 °C. (<b><span style="color:#3DF729">•</span></b>) TVC is represented by a continuous line (-) and <span class="html-italic">Listeria monocytogenes</span> (<b><span style="color:red">•</span></b>) is represented in dashed lines (---). Statistically important differences (<span class="html-italic">p</span> &lt; 0.05) were observed for <span class="html-italic">L. monocytogenes</span> between C and S samples.</p>
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<p>Population of the examined microorganisms and pH values in vacuum storage of non-inoculated feta cheese samples with edible film (mean values ± standard deviations) for (<b>a</b>): C samples stored at 4 °C, (<b>b</b>): FF samples stored at 4 °C, (<b>c</b>): SF samples stored at 4 °C, (<b>d</b>): C samples stored at 10 °C, (<b>e</b>): FF samples stored at 10 °C, (<b>f</b>): SF samples stored at 10 °C. (<b><span style="color:#3DF729">•</span></b>) Total viable counts, (<b><span style="color:#5B9BD5">•</span></b>) cocci/streptococci, (<b><span style="color:#ED7D31">•</span></b>) lactic acid bacteria, (<b><span style="color:#2F5496">•</span></b>) yeasts and molds are represented by a continuous line (-). pH values (<b><span style="color:#000000">•</span></b>) are indicated in the secondary axis and are represented with a dotted line (…). No statistically important differences were observed (<span class="html-italic">p</span> &gt; 0.05) except from cocci/streptococci at 4 °C for C and FF samples.</p>
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<p>Population of total viable counts (TVC) and <span class="html-italic">Listeria monocytogenes</span> in vacuum storage of inoculated feta cheese samples with edible film (mean values ± standard deviations) for (<b>a</b>): C samples stored at 4 °C, (<b>b</b>): FF samples stored at 4 °C, (<b>c</b>): SF samples stored at 4 °C, (<b>d</b>): C samples stored at 10 °C, (<b>e</b>): FF samples stored at 10 °C, (<b>f</b>): SF samples stored at 10 °C. (<b><span style="color:#3DF729">•</span></b>) TVC is represented by a continuous line (-) and <span class="html-italic">Listeria monocytogenes</span> (<b><span style="color:red">•</span></b>) is represented in dashed lines (---). No statistically important differences were observed (<span class="html-italic">p</span> &gt; 0.05).</p>
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<p>Sensory scores of aerobic (<b>a</b>), brine (<b>b</b>), vacuum (<b>c</b>), vacuum with edible films (<b>d</b>), storage of feta cheese samples during storage at 4 and 10 °C for appearance (Ap), texture (Te), aroma (Ar), taste (Ts), and total score (T). Dashed lines represent the end of shelf life.</p>
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<p>Raw Fourier transform infrared (FTIR) spectra, in the selected wavenumber range 1800–900 cm<sup>−1</sup>, corresponding to feta cheese samples stored under aerobic conditions (<b>a</b>), brine (<b>b</b>), vacuum packaging (<b>c</b>), and with edible film under vacuum packaging (<b>d</b>). Fresh samples (Day 0) are represented in black solid line (──), spoiled samples at 4 °C in green dashed line (<span style="color:#00B050">----</span>), and spoiled samples at 10 °C in red dashed line (<span style="color:red">----</span>).</p>
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<p>Indicative multispectral imaging (MSI) reflectance spectra (mean ± standard deviation) from the benchtop-MSI instrument, corresponding to feta cheese samples stored in aerobic conditions (<b>a</b>), brine (<b>b</b>), vacuum (<b>c</b>), and vacuum with edible film (<b>d</b>). Fresh samples (Day 0) are represented in black solid line (──), spoiled samples at 4 °C in green dashed line (<span style="color:#00B050">----</span>), and spoiled samples at 10 °C in red dashed line (<span style="color:red">----</span>).</p>
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<p>Indicative multispectral imaging (MSI) reflectance spectra (mean ± standard deviation) from the portable-MSI instrument, corresponding to feta cheese samples stored in aerobic conditions (<b>a</b>), brine (<b>b</b>), vacuum (<b>c</b>), and vacuum with edible film (<b>d</b>). Fresh samples (Day 0) are represented in black solid line (──), spoiled samples at 4 °C in green dashed line (<span style="color:#00B050">----</span>), and spoiled samples at 10 °C in red dashed line (<span style="color:red">----</span>).</p>
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17 pages, 4481 KiB  
Article
Gastric Cancer and Intestinal Metaplasia: Differential Metabolic Landscapes and New Pathways to Diagnosis
by Seong Ji Choi, Hyuk Soon Choi, Hyunil Kim, Jae Min Lee, Seung Han Kim, Jai Hoon Yoon, Bora Keum, Hyo Jung Kim, Hoon Jai Chun and Youngja H. Park
Int. J. Mol. Sci. 2024, 25(17), 9509; https://doi.org/10.3390/ijms25179509 - 1 Sep 2024
Viewed by 747
Abstract
Gastric cancer (GC) is the fifth most common cause of cancer-related death worldwide. Early detection is crucial for improving survival rates and treatment outcomes. However, accurate GC-specific biomarkers remain unknown. This study aimed to identify the metabolic differences between intestinal metaplasia (IM) and [...] Read more.
Gastric cancer (GC) is the fifth most common cause of cancer-related death worldwide. Early detection is crucial for improving survival rates and treatment outcomes. However, accurate GC-specific biomarkers remain unknown. This study aimed to identify the metabolic differences between intestinal metaplasia (IM) and GC to determine the pathways involved in GC. A metabolic analysis of IM and tissue samples from 37 patients with GC was conducted using ultra-performance liquid chromatography with tandem mass spectrometry. Overall, 665 and 278 significant features were identified in the aqueous and 278 organic phases, respectively, using false discovery rate analysis, which controls the expected proportion of false positives among the significant results. sPLS-DA revealed a clear separation between IM and GC samples. Steroid hormone biosynthesis, tryptophan metabolism, purine metabolism, and arginine and proline metabolism were the most significantly altered pathways. The intensity of 11 metabolites, including N1, N2-diacetylspermine, creatine riboside, and N-formylkynurenine, showed significant elevation in more advanced GC. Based on pathway enrichment analysis and cancer stage-specific alterations, we identified six potential candidates as diagnostic biomarkers: aldosterone, N-formylkynurenine, guanosine triphosphate, arginine, S-adenosylmethioninamine, and creatine riboside. These metabolic differences between IM and GC provide valuable insights into gastric carcinogenesis. Further validation is needed to develop noninvasive diagnostic tools and targeted therapies to improve the outcomes of patients with GC. Full article
(This article belongs to the Special Issue Advances in Rare Diseases Biomarkers)
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Figure 1

Figure 1
<p>Schematic overview of the biomarker identification criteria applied in this study. (<b>a</b>) The metabolic overview started with the extraction of metabolites from 37 gastric cancer (GC) and intestinal metaplasia (IM) tissues. (<b>b</b>) The scheme of untargeted metabolomics analysis. (1) Metabolites detection was done using Q-TOF-MS, generating mass spectra. (2) Data preprocessed using apLCMS version 6.3.8 and xMSanalyzer version 2.0.6.1. (3) Metabolic profiling with Manhattan plot with false discovery rate (FDR) analysis and sparse partial least square discriminant analysis (sPLS-DA). (4) Pathway analysis with Kyoto Encyclopedia of Genes and Genomes (KEGG). (5) Biomarker quantification using multiple reaction monitoring (MRM). apLCMS: adaptive processing of liquid chromatography-mass spectrometry. FDR, false discovery rate; GC, gastric cancer; IM, intestinal metaplasia; KEGG, Kyoto Encyclopedia of Genes and Genomes; MS, mass spectrometery; Q-TOF-MS, quadrupole time-of-flight mass spectrometry; sPLS-DA: sparse partial least square discriminant analysis.</p>
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<p>Analytical performance evaluation by comparing pool and case samples. (<b>a</b>) PCA using 665 significant features (FDR q ≤ 0.05) from aqueous extraction data. (<b>b</b>) PCA using 278 significant features (FDR q ≤ 0.05) from organic extraction data. FDR, false discovery rate; GC, gastric cancer; IM, intestinal metaplasia; PCA, principal component analysis; PC1, principal component 1; PC2, principal component 2; PC3, principal component 3; QC, quality control.</p>
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<p>Manhattan plot, PCA, and sPLS-DA between IM and GC. The Manhattan plot presents the significant features (FDR q ≤ 0.05) as colored dots, while their distribution is expressed in <span class="html-italic">m</span>/<span class="html-italic">z</span>. (<b>a</b>) Manhattan plot showing 665 significant features (FDR q ≤ 0.05) derived from the aqueous data. (<b>d</b>) Manhattan plot with 278 significant features (FDR q ≤ 0.05) derived from the organic data. PCA shows the separation of samples: (<b>b</b>) aqueous data and (<b>e</b>) organic data. sPLS-DA shows the separation of samples: (<b>c</b>) aqueous data and (<b>f</b>) organic data. PCA, principal component analysis; PC1, principal component 1; PC2, principal component 2, sPLS-DA, sparse partial least squares discriminant analysis.</p>
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<p>Overview of the pathway analysis of the significant metabolites extracted from the combined aqueous and organic phases. (<b>a</b>) The bubble plot shows the pathways by impact (x-axis) and −log<sub>10</sub>(<span class="html-italic">p</span>) (y-axis). The color and size of each bubble represent the −log<sub>10</sub>(<span class="html-italic">p</span>) and impact, represented as color and size keys, respectively. (<b>b</b>) The top 16 pathways based on the −log<sub>10</sub>(<span class="html-italic">p</span>) are listed alongside their match status, indicating the hit metabolites to whole metabolites involved in each pathway, <span class="html-italic">p</span>-value, and impact.</p>
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<p>Analysis of significantly altered metabolites between GC and IM in the steroid hormone biosynthesis pathway from the KEGG pathway. (<b>a</b>) Pathway of androgen steroid and (<b>b</b>) pathway of mineralocorticoid. All metabolites in the figure a and b were significantly altered (FDR, q ≤ 0.05). Boxplots illustrate the upper quartile, median (dashed bar), and lower quartile, with whiskers indicating the maximum and minimum values. FDR, false discovery rate; GC, gastric cancer; IM, intestinal metaplasia; KEGG, Kyoto Encyclopedia of Genes and Genomes.</p>
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<p>Analysis of significantly altered metabolites between GC and IM in the tryptophan metabolism pathway from the KEGG pathway. All metabolites in the figure were significantly altered (FDR, q ≤ 0.05). Boxplots illustrate the upper quartile, median (dashed bar), and lower quartile, with whiskers indicating the maximum and minimum values. FDR, false discovery rate; GC, gastric cancer; IM, intestinal metaplasia; KEGG, Kyoto Encyclopedia of Genes and Genomes.</p>
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<p>Analysis of significantly altered metabolites between GC and IM in the purine metabolism pathway from the KEGG pathway. All metabolites in the figure were significantly altered (FDR, q ≤ 0.05). Boxplots illustrate the upper quartile, median (dashed bar), and lower quartile, with whiskers indicating the maximum and minimum values. FDR, false discovery rate; GC, gastric cancer; GTP, guanosine triphosphate; IM, intestinal metaplasia; KEGG, Kyoto Encyclopedia of Genes and Genomes.</p>
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<p>Analysis of significantly altered metabolites between GC and IM in the arginine and proline metabolism pathways from the KEGG pathway. All metabolites in the figure were significantly altered (FDR, q ≤ 0.05). Boxplots illustrate the upper quartile, median (dashed bar), and lower quartile, with whiskers indicating the maximum and minimum values. FDR, false discovery rate; GC, gastric cancer; IM, intestinal metaplasia; KEGG, Kyoto Encyclopedia of Genes and Genomes.</p>
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<p>Relative metabolite intensities in tissues across various stages of GC at diagnosis. Boxplots illustrate the upper quartile, median (dashed bar), and lower quartile, with whiskers indicating the maximum and minimum values. Relative intensities of significant compounds correlated with four stages of GC. * <span class="html-italic">p</span> ≤ 0.05. GC, gastric cancer.</p>
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12 pages, 1560 KiB  
Article
Pilot Study on the Use of Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy for Diagnosing and Characterizing Cardiac Amyloidosis
by Charlotte Delrue, Annelore Vandendriessche, Amélie Dendooven, Malaïka Van der Linden, Marijn M. Speeckaert and Sander De Bruyne
Int. J. Mol. Sci. 2024, 25(17), 9358; https://doi.org/10.3390/ijms25179358 - 29 Aug 2024
Viewed by 447
Abstract
Amyloidosis diagnosis relies on Congo red staining with immunohistochemistry and immunofluorescence for subtyping but lacks sensitivity and specificity. Laser-microdissection mass spectroscopy offers better accuracy but is complex and requires extensive sample preparation. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy offers a promising alternative [...] Read more.
Amyloidosis diagnosis relies on Congo red staining with immunohistochemistry and immunofluorescence for subtyping but lacks sensitivity and specificity. Laser-microdissection mass spectroscopy offers better accuracy but is complex and requires extensive sample preparation. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy offers a promising alternative for amyloidosis characterization. Cardiac tissue sections from nine patients with amyloidosis and 20 heart transplant recipients were analyzed using ATR-FTIR spectroscopy. Partial least squares discriminant analysis (PLS-DA), principal component analysis (PCA), and hierarchical cluster analysis (HCA) models were used to differentiate healthy post-transplant cardiac tissue from amyloidosis samples and identify amyloidosis subtypes [κ light chain (n = 1), λ light chain (n = 3), and transthyretin (n = 5)]. Leave-one-out cross-validation (LOOCV) was employed to assess the performance of the PLS-DA model. Significant spectral differences were found in the 1700–1500 cm−1 and 1300–1200 cm−1 regions, primarily related to proteins. The PLS-DA model explained 85.8% of the variance, showing clear clustering between groups. PCA in the 1712–1711 cm−1, 1666–1646 cm−1, and 1385–1383 cm−1 regions also identified two clear clusters. The PCA and the HCA model in the 1646–1642 cm−1 region distinguished κ light chain, λ light chain, and transthyretin cases. This pilot study suggests ATR-FTIR spectroscopy as a novel, non-destructive, rapid, and inexpensive tool for diagnosing and subtyping amyloidosis. This study was limited by a small dataset and variability in measurements across different instruments and laboratories. The PLS-DA model’s performance may suffer from overfitting and class imbalance. Larger, more diverse datasets are needed for validation. Full article
(This article belongs to the Section Molecular Oncology)
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Figure 1
<p>Standard normal variate-normalized absorbance spectra of amyloidosis-affected cardiac tissue (blue line) and post-transplant control cardiac tissue (green line) in the spectral region of 1750–1000 cm<sup>−1</sup>, illustrating the associated biomolecules represented by the wavenumbers in the mid-infrared region. The amide I band (1700–1600 cm<sup>−1</sup>) arises by C=O stretching vibrations, indicative of protein secondary structure. The amide II band (1700–1600 cm<sup>−1</sup>) represents N-H bending coupled with C-N stretching and the amide III band (1300–1200 cm<sup>−1</sup>) contains a mixture of C-N stretching and N-H bending, which are also related to protein structure.</p>
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<p>Partial least squares discriminant analysis (PLS-DA) and principal component analysis (PCA) model discriminating amyloidosis-affected cardiac tissue and post-transplant control cardiac tissue. (<b>A</b>) Score plot of the first two components of the PLS-DA model showing visible clustering between amyloidosis-affected cardiac tissue (green dots) and control cardiac tissue (blue dots). The ellipses surrounding the scatter plots represent the 95% confidence intervals (CI). (<b>B</b>) Feature importance plot of the PLS-DA model differentiating between amyloidosis-affected cardiac tissue and control cardiac tissue. The average second derivative spectra are shown for both amyloidosis (green line) and control cardiac tissue (blue line). The coefficients of the plot indicate the contribution of each wavenumber to the model with positive coefficients indicating higher probabilities of belonging to the amyloidosis class, and negative coefficients indicating lower probabilities. (<b>C</b>) Score plot of the first two components of the PCA model in the 1712–1711 cm<sup>−1</sup>, 1666–1646 cm<sup>−1</sup>, and 1385–1383 cm<sup>−1</sup> regions demonstrating visible clustering between amyloidosis-affected cardiac tissue (green dots) and control cardiac tissue (blue dots). The ellipses surrounding the scatter plots represent the 95% CI.</p>
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<p>Second-derivative infrared spectra, principal component analysis (PCA), and hierarchical cluster analysis (HCA) model discriminating the three amyloid types. (<b>A</b>) Second-derivative absorbance spectra of κ light chain (red lines), λ light chain (green lines), and transthyretin (blue lines) cardiac amyloidosis in the amide I region (1700–1600 cm<sup>−1</sup>). (<b>B</b>) The dendrogram of the HCA shows clear clustering of the distinct amyloid types: transthyretin (blue lines), κ light chain (red line), and λ light chain (green lines). (<b>C</b>) Score plot of the first two components of the PCA model in the specific spectral region of 1646–1642 cm<sup>−1</sup> demonstrating visible clustering between the distinct amyloidosis types: κ light chain (red dot), λ light chain (green dots), and transthyretin (blue dots).</p>
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