Search Results (7,742)

Volatile organic compounds (VOCs) are increasingly recognized as metabolic byproducts of viral infection and may serve as olfactory cues detectable by trained scent dogs. This study examined whether dogs could distinguish cell culture samples infected with murine hepatitis virus strain 1 (MHV-1), a biosafety level 2 coronavirus model, from uninfected controls. Parallel chemical analysis using gas chromatography–mass spectrometry (GC-MS) identified 14 VOCs in infected and 12 in control samples. Notably, 3-heptanone and 1-nonanol were unique to infected samples, while others such as acetophenone, nonanal, decanal, and benzaldehyde were significantly elevated—often by 1.5 to 3 times—in infected cultures. Two trained dogs demonstrated high detection sensitivity (0.95) for infected samples compared to a previously trained odor cinnamon group (0.88) and responded with shorter latency (p = 0.04), suggesting perceptual salience of infection-related VOCs. Reliable detection required pooled volumes (~600 µL), suggesting a threshold effect related to VOC concentration. Additionally, a Random Forest-based machine learning classifier trained on the GC-MS-obtained VOC profiles achieved a cross-validated accuracy of 0.82 (SD = 0.25). These findings suggest that dogs use quantitative VOC differences, rather than unique compounds, for detection. The study provides a validated experimental framework for olfactory diagnostics of viral infections and highlights the potential of scent dogs as non-invasive biosensors in both veterinary and public health contexts. Full article

Acrylate-based self-polishing copolymer antifouling paint particles (SPC-APPs) are persistent micropollutants that act as carriers for biocidal heavy metals, posing significant ecological hazards to aquatic ecosystems. Despite their toxicity, the occurrence, characterization, and metal-leaching risks of SPC-APPs in estuarine environments remain largely understudied. This study investigated the contamination characteristics of SPC-APPs in surface sediments from the Yangtze River Estuary, a hotspot of shipping activity. A multi-technique analytical protocol was employed, combining density separation with scanning electron microscopy–energy-dispersive spectroscopy (SEM-EDS), inductively coupled plasma mass spectrometry (ICP-MS), and pyrolysis–gas chromatography/mass spectrometry (Py-GC/MS) to characterize the morphology, quantify particle abundance, and assess the correlation between SPC-APPs and sedimentary heavy metals. SPC-APPs were ubiquitously detected across all sampling sites, with abundances ranging from (0.82 ± 0.15) × 10³ to (3.65 ± 0.42) × 10³ particles g⁻¹ dry sediment. A distinct distribution property (South Branch > North Branch > offshore shoal) was identified, primarily driven by shipping density and hydrodynamic sorting. Morphologically, particles exhibited irregular, abraded surfaces, with EDS confirming Cu (1.76~5.63 wt%) and Zn (0.27~3.65 wt%) as major metallic components. Py-GC/MS analysis identified specific mass fragments (m/z 41, 69, 87) as diagnostic markers. Strong positive correlations were observed between SPC-APP abundance and sediment Cu (r = 0.82, p < 0.01) and Zn (r = 0.76, p < 0.01) concentrations, indicating that these particles are a primary source of metal contamination. Ecological risk assessment based on sediment quality benchmarks showed that Cu in the South Branch reached 82~91% of the probable effect concentration (PEC), highlighting potential risks to benthic organisms. This study provides critical baseline data on the distribution and speciation of SPC-APPs, underscoring their role as vectors for toxic metals and the need for targeted pollution control in high-shipping-intensity estuarine regions. Full article

A functional Huangjiu-based liqueur (called by Lujiu in China), a type of Chinese rice wine, was developed by incorporating Chinese gall leaven, as a medicinal–edible homologous ingredient, into the fermentation process to enhance its bioactivity. The physicochemical properties and enzymatic activities were investigated and found that supplementation with 2% (v/v) Chinese gall leaven optimized fermentation efficiency and substrate utilization. The co-fermentation significantly elevated the concentrations of bioactive compounds and improved antioxidant capacity, particularly free radical scavenging activity. Compared to traditional Chinese rice wine, the supplemented variant exhibited markedly higher levels of malic acid and phenolic acids. GC-MS analysis identified 85 and 84 volatile flavor compounds in the two supplemented variants, respectively, exceeding the 70 compounds detected in traditional Huangjiu. GC-IMS further revealed significant enrichment of key alcohols (e.g., 3-methyl-1-butanol, 2-methyl-1-propanol) and aldehydes (e.g., propanal, acetaldehyde) in the supplemented group. Microbial community analysis indicated distinct shifts, with increased relative abundances of Pediococcus, Lactiplantibacillus, Aspergillus, and Saccharomyces in the Chinese gall leaven-supplemented fermentation. These results suggest that the native microflora and enzymatic systems of Chinese gall leaven could enhance microbial metabolism and fermentation efficiency, thus contributing to the unique characteristics of rice wine and providing a novel strategy for functional Huangjiu-based liqueur production. Full article

Ophiocordyceps sinensis, a fungus parasitic on insects, attracts interest due to its unique medicinal applications and complex ecological interactions. The potential relationship between codon usage bias and the parasitic relationship between O. sinensis and Thitarodes xiaojinensis was explored by analyzing the nuclear genomes and mitochondrial genomes of the two. The nuclear genomes showed contrasting preferences: O. sinensis sclerotium exhibited strong GC-ending codon bias (GC3 = 66.13%), while T. xiaojinensis favored AT-ending codons (GC3 = 49.14%). Conversely, both mitochondrial genomes displayed a strong preference (>70% AT) for AT-ending codons. Optimal codon analysis revealed 25 (GC-ending) in O. sinensis and 28 (GC-ending) in T. xiaojinensis nuclear genomes, with overlaps for Leu, Val, Ser, and Pro. The mitochondrial genomes had fewer optimal codons (16 and 13, AT-ending), showing limited overlap (Phe, Leu, Asp, Ser). Neutral plotting analysis, effective number of codons analysis, relative synonymous codon usage analysis, and parity bias analysis showed that the codon usage preferences of the nuclear genomes and mitochondrial genomes of O. sinensis and T. xiaojinensis are jointly affected by selection and mutation pressure. Natural selection predominates in nuclear genomes, while mutation pressure dominates in mitochondrial genomes. This provides new molecular insights into their host–parasite specificity. Full article

Green cosmetics are primarily based on plant-derived ingredients and use sustainable biotechnological tools for their preparation. The present research aimed to investigate the Usnea barbata (U. barbata) extract in Jojoba oil (JO) enriched with 5% Peppermint oil (PEO) and 10% Vitamin E, as a potential natural product for skin applications. The U. barbata oil extract (UBPJO) was obtained through cold maceration. Phytochemical screening was performed using Gas Chromatography/Mass Spectrometry (GC-MS), Folin–Ciocalteu method, and Graphite-Furnace Atomic Absorption Spectrophotometry (GFAAS). Fourier Transform Infrared Spectroscopy (FTIR) and Atomic Force Microscopy (AFM) were used to evaluate the physicochemical properties. Then, rheological characteristics and oxidation stability (measured as the time to reach the oxidation starting point, induction period (IP)) of both oil samples (UBPJO and oil mixture alone (PJO) were investigated. Total phenolic content (TPC) in UBPJO was 2.5 times higher than in PJO (p < 0.05), while heavy metal levels (As and Pb) were slightly higher (p > 0.05). UBPJO has higher shear stress, viscosity, and spreadability than PJO, but the differences are not significant (p > 0.05). Finally, IP measurements indicated appreciable oxidative stability (UBPJO vs. PJO: 153.02 h vs. 137.35 h, p > 0.05). The phytochemical composition and physicochemical properties support the inclusion of UBPJO in various skincare formulations. Full article

Aluminum chloride (AlCl₃), a widely used inorganic polymeric coagulant in everyday products and industrial materials, has been associated with male reproductive toxicity, though its molecular mechanisms remain poorly understood. To investigate the complex molecular mechanisms underlying GC-1spg cells’ responses to AlCl₃ exposure, transcriptome and small RNA (sRNA) sequencing analyses were performed. Transcriptome sequencing identified 1168 differentially expressed genes (DEGs), while sRNA sequencing detected 65 differentially expressed microRNAs (DEMs). An mRNA–miRNA regulatory network was established, and functional enrichment analysis showed that its target genes were significantly associated with multiple signaling pathways, particularly the p53 pathway. Further validation via Western blot and Hoechst 33342 staining assays confirmed that GC-1spg cells underwent apoptosis upon AlCl₃ exposure via the p53 signaling pathway. Among the identified DEMs, mmu-miR-503-5p was found to enhance GC-1spg cells’ tolerance to AlCl₃-induced stress. Moreover, dual-luciferase reporter assays and RT-qPCR confirmed that mmu-miR-503-5p directly binds to the Islr gene, which plays a role in modulating GC-1spg cell tolerance to AlCl₃-induced stress. These findings provide critical insights into the molecular mechanisms governing GC-1spg cells’ responses to AlCl₃ exposure. Full article

Consumer demand is growing for traceable, high-quality Cinnamomum cassia with defined sensory attributes. However, research linking cultivar morphology to these specific flavor signatures remains scarce. This study elucidated the relationships between phenotypic traits, volatile constituents, and key aroma characteristics of three C. cassia cultivars (Xijiang [XJ], Dongxing [DX], and Qinghua [QH]) using phenotypic evaluation, headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS-SPME-GC-MS), and a combination of relative odor activity value and principal component analysis (rOAV-PCA). XJ exhibited an intensely spicy aroma, attributable to its high trans-cinnamaldehyde content (718.76 ± 60.08 mg/g). In contrast, DX showed the highest δ-cadinene level (44.86 ± 4.48 mg/g) and a complex spicy–woody–sweet profile, shaped by sesquiterpenes such as α-humulene, α-copaene, caryophyllene, and β-caryophyllene. QH displayed both a high volatile oil yield (2.57 ± 0.28%) and a distinct herbal–woody character, primarily contributed by δ-cadinene and α-muurolene. This study constructed an integrated phenotype–chemistry–sensory map for C. cassia cultivars, facilitating cultivar discrimination, supporting flavor quality management, and enabling marker-assisted breeding for desirable aroma profiles. Full article

Given the growing consumer preference for plant-based proteins, improving their flavor profiles is essential for market success. Despite their nutritional benefits, plant proteins, such as walnut proteins, often suffer from weaker and less appealing flavors than those of animal proteins. This study investigated the pivotal role of amino acids in walnut aroma development during microwave treatment. Through gas chromatography mass spectrometry analysis of five walnut varieties, considerable differences in the aroma compound composition were identified with 13 key aroma components highlighted via relative odor activity value analysis. The present results demonstrated that methionine played a predominant role in pyrazine and heterocyclic compound production, underscoring its importance in walnut aroma formation. Thus, heat treatments, particularly microwave processing, show potential for enhancing flavor under the conditions investigated. These findings suggest a possible approach for improving flavor profiles in plant protein–based systems. Full article

Raisin syrup sourdough is a popular traditional leavening method in Japan, yet its specific impact on bread aroma evolution and shelf life stability remains scientifically underexplored. This study characterized the fermentation dynamics and volatile profiles of raisin syrup sourdough bread compared to a commercial yeast control over a 3-day shelf life, utilizing comprehensive two-dimensional gas chromatography–mass spectrometry (GC × GC-TOFMS) and primary metabolite profiling of sugars, amino acids, and organic acids. The analysis resolved over 760 volatiles and revealed a fundamental kinetic divergence. While the yeast control exhibited a 24 h metabolic lag, the raisin sourdough achieved rapid activation, establishing a higher initial volatile load immediately post-baking. Driven by lactic acid bacteria dominance and extensive proteolysis, the sourdough’s acidic environment facilitated the retention of fruity esters and malty branched-chain aldehydes while effectively suppressing lipid oxidation markers like 9,17-Octadecadienal. Key aromatic markers, including benzenepropanol and Octanoate <isopentyl->, were significantly elevated and stabilized in the sourdough group. These findings demonstrate that raisin syrup fermentation generates a superior, stable aromatic profile, providing a scientific basis for optimizing clean-label artisan bread production in the Japanese market. Full article

This study focuses on the Helan Mountain East Foothills region of Ningxia, a typical continental climate wine-growing area, with Cabernet Sauvignon grapes as the subject. It combines trimethylsilyl derivatization–Gas Chromatography–Mass Spectrometry (TMS-GC-MS) technology and the independently developed AntDAS-GCMS data analysis platform. The aim was to systematically characterize the temporal dynamics of primary and secondary polar metabolites throughout the entire growth cycle of Cabernet Sauvignon in this region. Results identified 50 metabolites exhibiting significant differences (fold change ≥1, p < 0.05) across growth stages, primarily comprising organic acids (18), sugars (7), and amino acids (13). Metabolite accumulation demonstrated distinct stage-specific patterns: organic acids (e.g., tartaric acid, malic acid) peaked before veraison and then declined significantly, while sugars (e.g., fructose) exhibited a marked increase in abundance during the late maturation stage. The underlying mechanisms of the relevant metabolic pathways require further validation through multi-omics approaches. This study elucidates the dynamic characteristics of primary and secondary metabolites throughout the entire growth stages of Cabernet Sauvignon in the region of Ningxia. It provides data support for understanding the metabolic basis of flavor development in grapes from this area and offers practical references for quality regulation and harvest timing optimization in local grape cultivation management. Full article

A novel Ag₃PO₄/BiVO₄ heterojunction was synthesized via a combined hydrothermal–in situ precipitation method. With an optimal Bi:Ag molar ratio of 1:2 and after calcination at 200 °C for 22 h, 0.9 g of this composite reduced the chemical oxygen demand (COD) of landfill leachate tailwater from 232 mg·L⁻¹ to 142 mg·L⁻¹ and its UV₂₅₄ absorbance from 0.22 to 0.156 under visible light irradiation within 140 min. The material exhibited a bandgap of 2.56 eV, along with enhanced visible-light absorption and improved charge-carrier separation efficiency. In the Ag₃PO₄/BiVO₄/peroxymonosulfate (PMS)/visible light system, using 0.5 g of catalyst and 2.0 g·L⁻¹ of PMS at pH 11 reduced the COD from 242 mg·L⁻¹ to 138 mg·L⁻¹. A subsequent two-stage treatment process, integrating the Ag₃PO₄/BiVO₄/PMS/vis and P25/UV process, achieved a final tailwater COD of 90 mg·L⁻¹—meeting standard discharge limits—and a 69.5% removal of humic-like substances. The heterojunction catalyst retained its activity over four consecutive cycles. Radical quenching experiments and electron paramagnetic resonance (EPR) spectroscopy identified photogenerated holes (h⁺), hydroxyl radicals(·OH), and sulfate radicals (SO₄⁻·) as the primary reactive species. Gas chromatography–mass spectrometry (GC–MS) analysis identified intermediate organic compounds and proposed plausible degradation pathways. These results support a reaction mechanism in which h⁺ oxidizes H₂O to generate ·OH, while PMS accepts electrons to produce SO₄⁻· and further ·OH radicals, leading to effective pollutant mineralization. Collectively, this solar-driven, sulfate radical-based advanced oxidation process offers an energy-efficient strategy with reduced chemical consumption for the sustainable treatment of refractory wastewater. Full article

Plants living in wetland environments (hydrophytes) have developed metabolic adaptations to cope with hypoxia. However, the specific metabolic signatures underlying this adaptation in naturally occurring hydrophytes, compared to their mesophytic relatives, remain insufficiently explored. GC-MS was used to carry out a comparative metabolic profiling of leaves from two pairs of closely related species (the hydrophytes Iris pseudacorus and Comarum palustre versus the mesophytes I. sibirica and Argentina anserina). In total, approximately 260 compounds were detected, of which roughly 100 were annotated. Using Principal Component Analysis, we revealed that the primary source of metabolic variation was phylogenetic (genus/tribe affiliation), while a secondary gradient correlated with ecological adaptation to submergence. A common adaptive metabolic signature of hydrophytes was identified, including the accumulation of dicarboxylic acids from Krebs cycle (succinate, fumarate) and glycolytic metabolites (pyruvate), suggesting a restructuring of energy metabolism under oxygen deficiency. Furthermore, hydrophytes, particularly I. pseudacorus, accumulated higher levels of soluble sugars (sucrose, fructose, glucose) and amino acids, thereby supporting energy supply and alternative NAD(P)H reoxidation pathways. Species-specific differences in the accumulation of antioxidants (e.g., flavonoids, ascorbate) were also observed, indicating diverse strategies for managing oxidative stress. Our findings contribute to identifying a “metabolic fingerprint” associated with waterlogging tolerance. Full article

Background: Hypoxia is a key driver of cancer progression. However, its specific prognostic significance in gastric cancer (GC) remains insufficiently characterized. Methods: Single-sample gene set enrichment analysis (ssGSEA), weighted gene co-expression network analysis (WGCNA), univariate Cox regression, and least absolute shrinkage and selection operator (LASSO) regression were employed to identify a hypoxia-related prognostic signature. Subsequently, immune microenvironment profiling and single-cell RNA sequencing analyses were employed to further characterize the biological characteristics of the signature. In addition, quantitative real-time polymerase chain reaction (qPCR) was used to validate the expression levels of key hypoxia-associated genes in human GC tissues. Results: Elevated hypoxia levels were linked to worse survival outcomes in GC patients. Through integrated WGCNA, Cox, and LASSO analyses, a hypoxia-related prognostic signature (HYS) consisting of four genes—SPARC, AXL, NRP1, and VCAN—was established. Patients in the HYS-high group exhibited markedly poorer overall survival than their HYS-low counterparts [p = 0.000126, hazard ratio (HR) = 1.936]. Moreover, the HYS-high group exhibited increased infiltration of resting CD4⁺ memory T cells, monocytes, M2 macrophages, and resting mast cells, as well as elevated expression of immunosuppressive molecules, including PDCD1LG2 and HAVCR2. Single-cell RNA sequencing analysis revealed that the signature genes were predominantly expressed in cancer-associated fibroblasts. Consistently, qPCR analysis in five paired GC and para-carcinoma tissues confirmed higher expression of these genes in tumor samples (p < 0.01). Conclusions: Our findings indicate that hypoxia is a critical determinant of prognosis in GC and is closely associated with an immunosuppressive tumor microenvironment, highlighting its potential value as a prognostic biomarker and therapeutic target. Full article

Background/Objectives: Cardiovascular involvement drives morbidity and mortality in systemic lupus erythematosus (SLE). Echocardiography has limited predictive value for long-term outcomes, and subclinical right ventricular (RV) remodeling is poorly characterized. Metabolic dysregulation may influence immune activation and myocardial injury. This study investigates whether baseline metabolomic profiles are associated with longitudinal RV changes and disease progression in SLE. Methods: In this prospective, single-center study, patients with established SLE and no known cardiac disease underwent baseline clinical assessment, plasma metabolomic profiling, and advanced echocardiography, including 3D RV analysis. Echocardiography was repeated after 6 years. Metabolomics was performed using NMR spectroscopy and GC–MS. Disease progression was assessed via the SLICC/ACR damage index (SDI), defining clinical stability as ΔSDI = 0 and worsening as ΔSDI ≥ 1. Results: Twenty-five patients completed the follow-up (88% female; mean age 51 ± 13 years). Despite normal echocardiographic values, subtle but significant RV changes were observed, remaining within reference ranges, including mild declines in fractional area change and septal longitudinal strain (p < 0.05). Clinically worsened patients showed reduced TAPSE, while stable patients had slight increases (p < 0.05). Multivariate metabolomic analysis distinguished stable from worsened patients (R²Y = 0.772; Q² = 0.483), primarily driven by higher 2-aminoheptanedioic acid values in those with progression (p < 0.05), along with trends toward higher fumarate and lower fructose and glucopyranose. Conclusions: Baseline metabolomic and advanced echocardiographic profiling may identify SLE patients at risk of disease progression. Longitudinal echocardiography enables monitoring of subtle RV changes, supporting personalized surveillance to detect early subclinical trajectories before overt dysfunction develops. Full article

The variability in outcomes among individuals is caused by multiple factors, including genetic variations in drug transporter genes known as ABCs. This study investigates the clinical effect of single-nucleotide variants (SNVs) in the ABCC1/MRP1, ABCC2/MRP2, and ABCC4/MRP4 genes on the clinical response and relapse of pediatric patients with central nervous system tumors. In a cohort-based association study involving 111 cancer patients, genotyping of ABCC1/MRP1, ABCC2/MRP2, and ABCC4/MRP4 was conducted using real-time PCR with TaqMan probes. Treatment response was evaluated using the Response Assessment in Neuro-Oncology (RANO) criteria. Univariate and multivariate analyses were conducted using the Cox proportional hazards (adjusted) model. Multivariate analysis adjusted for sex and age showed a significant association between ABCC1 r.5540out G>C; rs12921623 in the gene and non-response to treatment in the codominant model [HR] 2.095, 95% CI 1.202–3.650, p = 0.009, and in the dominant model [HR] 2.025, 95% CI 1.199–3.421, p = 0.008, and an increased risk of relapse in the codominant model [HR] 9.09, 95% CI 1.04–78.85, p = 0.04, and in the dominant model [HR] 3.912, 95% CI 1.139–13.436, p = 0.03. Furthermore, a significant association was found between ABCC2 c. 3972 C>T; rs3740066 and relapse in the recessive model [HR] 3.5, 95% CI 1.02–12.17, p = 0.04. Our findings indicate that ABCC1 r.5540 G>C SNV and ABCC2 c. 3972 C>T SNV are significant predictors of non-response and relapse in this group of pediatric patients with central nervous system tumors. Full article