Search Results (159)

Sweet taste plays a pivotal role in human dietary behavior and metabolic regulation. With the increasing incidence of metabolic disorders linked to excessive sugar intake, the development and accurate evaluation of new sweeteners have become critical topics in food science and public health. However, the structural diversity of sweeteners and their complex interactions with sweet taste receptors present major challenges for standardized sweetness detection. This review offers a comprehensive and up-to-date overview of sweet taste transmission mechanisms and current detection methods. It outlines the classification and sensory characteristics of both conventional and emerging sweeteners, and explains the multi-level signaling pathway from receptor binding to neural encoding. Key detection techniques, including sensory evaluation, electronic tongues, and biosensors, are systematically compared in terms of their working principles, application scope, and limitations. Special emphasis is placed on advanced biosensing technologies utilizing receptor–ligand interactions and nanomaterials for highly sensitive and specific detection. Furthermore, an intelligent detection framework integrating molecular recognition, multi-source data fusion, and artificial intelligence is proposed. This interdisciplinary approach provides new insights and technical solutions to support precise sweetness evaluation and the future development of healthier food systems. Full article

Mangrove ecosystems, serving as critical barriers at land–sea interfaces, face increasing threats from microplastic pollution. This study investigates the spatial distribution, diversity, and ecological risks of microplastics in sediments from the Zhangjiang Estuary mangroves, in southeastern China. Sampling was conducted along two gradients: upstream–downstream and interior–edge habitats. The results revealed an average microplastic abundance of 219.5 ± 21.7 items·kg⁻¹, dominated by fragments (53.3%) and fibers (35.0%). Additionally, 27.8% of the particles were in the 63–200 μm range, while 38.3% fell within the 200–500 μm range. A longitudinal decline in abundance from upstream to downstream was observed. Meanwhile, interior habitats exhibited significantly higher microplastic accumulation (292.86 ± 31.49 items·kg⁻¹) than edge zones (142.50 ± 17.87 items·kg⁻¹) (p < 0.05). The diversity index decreased downstream, with higher diversity in interior habitats, likely due to reduced terrestrial microplastic inputs and stronger tidal sorting in those areas. The ecological risk assessments indicated lower risks in Zhangjiang mangroves compared to global counterparts, though risks were elevated in interior habitats due to higher abundances of hazardous polymers (PVC, PS, PE). This study highlights the role of mangroves as microplastic sinks and advocates for multidimensional risk assessments integrating physical characteristics to guide conservation strategies in vulnerable estuarine ecosystems. Full article

Investigating the functional interactions between rumen microbial fermentation and epithelial mitochondrial dynamics/energy metabolism in Tibetan sheep at different altitudes, this study examined ultrastructural changes in rumen epithelial tissues, expression levels of mitochondrial dynamics-related genes (fusion: Mfn1, Mfn2, OPA1, Mic60; fission: Drp1, Fis1, MFF), and ketogenesis pathway genes (HMGS2, HMGCL) in Tibetan sheep raised at three altitudes (TS 2500m, TS 3500m, TS 4500m). Correlation analysis was performed between rumen microbiota/metabolites and mitochondrial energy metabolism. Results: Ultrastructural variations were observed across altitudes. With increasing altitude, keratinized layer became more compact; desmosome connections between granular layer cells increased; mitochondrial quantity and distribution in spinous and basal layers increased. Mitochondrial dynamics regulation: Fission genes (FIS1, DRP1, MFF) showed significantly higher expression at TS 4500m (p < 0.01); fusion genes (Mfn1, OPA1) exhibited altitude-dependent upregulation. Energy metabolism markers: Pyruvate (PA) decreased significantly at TS 3500m/TS 4500m (p < 0.01); citrate (CA) increased with altitude; NAD⁺ peaked at TS 3500m but decreased significantly at TS 4500m (p < 0.01); Complex II (SDH) and Complex IV (CO) activities decreased at TS 4500m (p < 0.01). Ketogenesis pathway: β-hydroxybutyrate increased significantly with altitude (p < 0.01); acetoacetate peaked at TS 2500 m/TS 4500 m; HMGCS2 expression exceeded HMGCL, showing altitude-dependent upregulation at TS 4500m (p < 0.01). Microbiome–metabolism correlations: Butyrivibrio_2 and Fibrobacter negatively correlated with Mic60 (p < 0.01); Ruminococcaceae_NK4A214_Group positively correlated with Mfn1/OPA1 (p < 0.05); WGCNA identified 17 metabolite modules, with MEturquoise module positively correlated with DRP1/Mfn2/MFF (p < 0.05). Conclusion: Altitude-induced ultrastructural adaptations in rumen epithelium correlate with mitochondrial dynamics stability and ketogenesis upregulation. Mitochondrial fission predominates at extreme altitudes, while microbiota–metabolite interactions suggest compensatory energy regulation mechanisms. Full article

As high-quality sheep germplasm resources in China, Hu sheep are characterized by fast growth and development, high fecundity, and tolerance to drought and cold. Tibetan sheep, adapted to high-altitude environments, have developed strong environmental adaptability. To explore the differences in the interaction among rumen microbial flora, hepatic gluconeogenesis, and mitochondrial function between Tibetan sheep and Hu sheep in the Qinghai–Tibet Plateau, this study systematically compared and analyzed the rumen flora density, key enzyme activities related to hepatic gluconeogenesis and mitochondrial function, and the expression levels of related genes in Tibetan sheep and Hu sheep under identical feeding management conditions, followed by correlation analysis. The results showed that Hu sheep had significantly higher densities of Ruminobacteramylophilus (Ram) and Fibrobacter succinogenes (Fs) associated with starch and protein degradation (p < 0.01). The expression levels of Forkhead box O1 (FOXO1), pyruvate carboxylase (PC) activity, and adenosine triphosphate (ATP) content were also significantly higher than those in Tibetan sheep (p < 0.01). In contrast, Tibetan sheep had higher densities of Butyrivibrio fibrisolvens (Bf), Ruminococcus albus (Ra), Ruminococcus flavefaciens (Rf), etc., related to cellulose degradation (p < 0.01). The gluconeogenesis-related genes, Glucose-6-phosphatase catalytic subunit 1 (G6PC1) and phosphoenolpyruvate carboxykinase1 (PCK1), and the activities of phosphoenolpyruvate carboxykinase (PEPCK) and fructose-1,6-bisphosphatase (FBPase) were significantly higher in Tibetan sheep than in Hu sheep (p < 0.01). Mitochondrial function-related genes Mitofusin-1 (Mfn1), Mitofusin-2 (Mfn2), subunit 6 of ATP synthase (ATP6), cytochrome b (Cytb), etc., also showed significantly higher expression in Tibetan sheep (p < 0.01). While no significant differences were observed in the contents of citric acid (CA), pyruvic acid (PA), glucose (Glu), etc. (p > 0.05). Correlation analysis indicated that rumen flora was associated with the key enzyme activities and gene expressions of hepatic gluconeogenesis and mitochondrial function to varying degrees. In summary, Tibetan sheep exhibit strong fiber degradation capacity, the efficient utilization of gluconeogenic intermediates, and mitochondrial oxidative phosphorylation (OXPHOS) ability, forming adaptive strategies for high-altitude environments. By contrast, Hu sheep show efficient protein and starch degradation capacity, thereby enhancing the supply of gluconeogenic precursors. It is indicated that when introducing Hu sheep to high-altitude areas, dietary intervention can be used to regulate rumen microorganisms, such as increasing fiber-decomposing bacteria or enhancing mitochondrial oxidative capacity, to counteract metabolic limitations induced by hypoxia. Full article

Air quality in Guangdong Province has improved in recent years, but progress varies across different provincial sub-regions, particularly between Pearl River Delta (PRD) and non-PRD (NPRD) regions. To unveil possible causes of this, this study established a high-resolution gridded emission inventory for Guangdong (2006–2020) by integrating multi-year Point of Interest (POI) data and road network information. The spatiotemporal evolutions of anthropogenic sulfur dioxide (SO₂), nitrous oxide (NO_X), and particulate matter (PM₁₀ and PM_2.5) emissions were analyzed, with a focus on their impacts on PM_2.5 pollution using the CMAQ model. Spatial shifts in emission sources were quantified using spatial statistical methods, including the average nearest neighbor index (ANNI), kernel density analysis (KDA), standard deviational ellipse (SDE), and mean center (MC). From 2006 to 2020, emissions decreased significantly for SO₂ (88%), NO_X (26%), PM₁₀ (64%), and PM_2.5 (68%). Emission hotspots shifted toward NPRD regions, driven by stricter environmental policies and industrial restructuring, lowering PRD-to-NPRD emission ratios for SO₂ (from 1.25 to 0.87), NO_X (1.67–1.51), and PM₁₀ (0.94–0.89). The spatial evolution of emissions varied across sources. For example, the emission share of industrial sources in the PRD declined despite an increase in enterprises, whereas vehicle emissions remained concentrated in the PRD. CMAQ modeling results revealed that overall emission reductions from 2012 to 2020 lowered provincial PM_2.5 concentrations by 9.2–10.5 μg/m³. Accounting for spatial evolution further enhanced PM_2.5 reductions in the PRD by 1.4 μg/m³ (April) and 1.1 μg/m³ (October). Conversely, PM_2.5 improvements in NPRD regions weakened, with reductions declining by 0.2–3.2 μg/m³ (April) and 0.1–1.4 μg/m³ (October). These findings provide guidance for formulating region-specific strategies, aiming for more equitable air quality improvements across Guangdong. Full article

Background and Objectives: Identifying carriers of Pathogenic/Likely Pathogenic Variants in patients with dementia is crucial for risk stratification, particularly in individuals with a family history. This study developed and validated a clinical prediction model using whole-exome sequencing-confirmed cohorts. Methods: A total of 601 Chinese patients with dementia and a family history were enrolled at Peking Union Medical College Hospital, with 476 in a retrospective derivation cohort and 125 in a temporal validation cohort. Predictive factors included age at onset, APOE ε4 status, and family history characteristics. Model performance was assessed using discrimination and calibration metrics. Results: In the derivation cohort (median age at onset 66 years), 10.3% carried Pathogenic/Likely Pathogenic Variants. Among patients with dementia, those with age at onset < 55 years (OR 2.56, p = 0.0098), more than two affected relatives (OR 3.32, p = 0.0039), parental disease history (OR 4.72, p = 0.015), and early-onset cases in the family (OR 2.61, p = 0.0096) were positively associated with Pathogenic/Likely Pathogenic Variant carriage, whereas APOE ε4 carriage was inversely associated (OR 0.36, p = 0.0041). The model achieved an area under the curve of 0.776 (95% CI, 0.701–0.853) in the derivation cohort and 0.781 (95% CI, 0.647–0.914) in the validation cohort (median age at onset 58 years), with adequate calibration. Conclusions: This model demonstrated strong predictive performance for Pathogenic/Likely Pathogenic Variant carriage, supporting its clinical utility in guiding genetic testing. Further research is needed to refine the model. Full article

This study elucidated the regulatory mechanisms of age-related meat flavor precursors in naturally grazed Sunit sheep of different ages (6, 18, and 30 months) by analyzing their metabolite and mRNA profiles. The longissimus dorsi muscle was sampled from each group and subjected to metabolomics and transcriptomics analyses. A total of 395 differential metabolites (DMs) and 1482 differentially expressed genes (DEGs) were detected across the age groups. As the age increased, the expression levels of GOT1 and GLUL increased, activating arginine biosynthesis and alanine, aspartate, and glutamate metabolism pathways, which promoted the accumulation of umami compounds (L-glutamate and L-glutamine). Meanwhile, the expression level of LPIN1 increased with age, promoting glycerophospholipid metabolism and contributing to the development of lipid-related aroma. FADS1 and FADS2 expressed the highest levels at age Mth_18. This pattern influenced the unsaturated fatty acid biosynthesis pathway and consequently had a regulatory effect on the DHA levels. An amino acid metabolic regulatory network that involved arginine biosynthesis, alanine, aspartate and glutamate metabolisms, and arginine and proline metabolisms was established. This study provided insights into the variations in meat flavor precursors among sheep of different ages and elucidated the underlying regulatory mechanisms. Full article

To identify the molecular targets and possible mechanisms of isoliquiritigenin (ISO) in affecting chronic obstructive pulmonary disease (COPD) by regulating the glycolysis and phagocytosis of alveolar macrophages (AM). Datasets GSE130928 and GSE13896 were downloaded from the Gene Expression Omnibus (GEO) database. Genes related to glycolysis and phagocytosis phenotypes were obtained from the GeneCards and MSigDB databases, respectively. Weighted gene co-expression network analysis (WGCNA) and differential analysis were conducted on GSE130928 to identify potential target genes for COPD (gene list 1). ISO target genes were gathered from the Traditional Chinese Medicine System Pharmacology (TCMSP) database, as well as the Comparative Toxicogenomic Database (CTD) and PubChem databases (gene list 2). COPD-related targets were gathered from the CTD and GeneCards databases, and the predicted targets of COPD were obtained by taking the intersection of these sources (gene list 3). From the three gene lists, key pathways were identified. The protein–protein interaction (PPI) network was created by extracting the common genes found in all key pathways and ISO targets. Candidate therapeutic targets were identified using the Minimum Common Oncology Data Element (MCODE) algorithm. These targets were then intersected with glycolysis and phagocytic phenotype-associated genes. The resulting intersection underwent further screening using eight distinct machine learning methods to identify phenotype-related key therapeutic targets. Clinical diagnostic evaluations—including nomogram analysis, receiver operating characteristic (ROC) analysis, correlation studies, and inter-group expression comparisons—were subsequently performed on these key targets. The research findings were validated using the independent dataset GSE13896. Additionally, gene set enrichment analysis (GSEA) was conducted to explore their functional relevance. Immune cell profiling was performed using mRNA expression data from AM in COPD patients. Molecular docking was then carried out to predict interactions between ISO and the identified key target genes. Differential expression analysis and WGCNA module analysis identified a total of 890 potential targets for COPD. Additionally, 3265 predicted targets for COPD were obtained through the intersection of two disease databases. Database searches also yielded 142 targets for ISO. Enrichment analysis identified 20 key pathways, from which three key targets (AKT1, IFNG, and JUN) were ultimately selected based on their overlap with enriched genes, ISO targets, and glycolysis- and phagocytosis-related genes. They were also validated using external datasets. Further analysis of signaling pathways and immune cell profiles highlighted the influence of immune infiltration in COPD and underscored the critical role of macrophages in disease pathology. Molecular docking simulations predicted the binding interactions between ISO and the three key targets. AKT1, IFNG, and JUN may be the key targets of ISO in regulating glycolysis and phagocytosis to affect COPD. Full article

Taro (Colocasia esculenta (L.) Schott) is the fifth largest rhizome crop, and it is widely distributed in tropical and subtropical areas in the world. Vegetative propagation with virus-infected corms can lead to cultivar degradation, yield decline, and quality deterioration. In this study, the shoot apical meristems excised from taro corms infected with dasheen mosaic virus, which belongs to the genus Potyvirus in the family Potyviridae, were cultured and treated with exogenous abscisic acid and high sucrose concentrations to induce micro-corm formation. Subsequently, candidate genes involved in micro-corm expansion were screened via transcriptome sequencing analysis. The results revealed that the shoot apical meristems could grow into adventitious shoots on the medium 1 mg/L 6-benzylaminopurine + 0.3 mg/L 1-naphthaleneacetic acid, and reverse transcription–polymerase chain reaction detection indicated that dasheen mosaic virus had been successfully eliminated from the test-tube plantlets. Moreover, 8% sucrose or 3% sucrose + 5 μM abscisic acid likewise induced taro corm formation, and genes related to cell division and the cell cycle, as well as starch and sucrose metabolism pathways, were significantly enriched during taro corm expansion. Furthermore, the cyclin-dependent kinases genes, cell cycle protein kinase subunit genes, and cyclin B2 genes, which are related to cell division and the cell cycle, were upregulated with abscisic acid treatment on the 3rd day. The sucrose synthase genes, β-amylase genes, glycogen branching enzyme genes, and soluble starch synthase genes, which are related to starch and sucrose metabolism, were upregulated on the 15th day, indicating that cell division largely occurs during taro corm formation, whereas carbohydrates are synthesized during taro corm expansion. Full article

The extensive utilization of nano-zero-valent iron (nZVI) and its engineered derivatives has prompted significant environmental concerns, particularly regarding their phytotoxicological impacts, which remain inadequately characterized. This investigation systematically evaluated the phytotoxicological responses induced by nZVI, Chlorella vulgaris biochar (BC), and Chlorella vulgaris biochar loaded with nano-zero-valent iron (BC/nZVI) on mung bean seed germination and subsequent seedling development. The experimental data revealed that both the nZVI and BC/nZVI treatments significantly suppressed the germination indices, including germination rate, radicle and plumule elongation, and biomass accumulation, with nZVI demonstrating the most pronounced inhibitory effects. During the vegetative growth phases, nZVI exposure substantially impaired plant morphogenesis, manifested through reduced vertical growth, diminished fresh and dry biomass production, and the onset of premature foliar chlorosis, necrosis, desiccation, and, ultimately, plant mortality. A comparative analysis indicated that the BC/nZVI composites exhibited less severe photosynthetic inhibition relative to pristine nZVI. Biochemical assays demonstrated that nZVI exposure elicited the substantial upregulation in antioxidant enzyme activities, including superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), concomitant with abnormal ferric ion accumulation in root tissues. Notably, BC/nZVI composites demonstrated the partial mitigation of these physiological disturbances. These empirical findings underscore that excessive iron bioavailability from nZVI induces substantial phytotoxicological stress, while BC matrix incorporation provides the partial amelioration of these adverse effects on seedling ontogeny. Full article

The H12 subtypes of avian influenza viruses (AIVs) are globally prevalent in wild birds, occasionally spilling over into poultry. In this study, we isolated an H12N8 virus from ducks in a live poultry market. Full genomic analysis revealed that the virus bears a single basic amino acid in the cleavage site of the hemagglutinin gene. Phylogenetic analysis revealed that the eight gene segments of the H12N8 virus belong to the Eurasian lineage and the HA gene was clustered with wild bird-originated H12 viruses, with its NP gene showing the highest nucleotide similarity to 2013-like H7N9 viruses. The H12N8 virus replicated effectively in both mammalian and avian cells without prior adaptation. Moreover, the H12N8 virus could infect and replicate in the upper respiratory tract of BALB/c mice without prior adaptation. The H12N8 virus replicated and transmitted inefficiently in both ducks and chickens and hardly triggered high hemagglutination inhibition (HI) antibody titers in the inoculated and contact animals. These results suggest that the wild bird-origin H12N8 virus has reassorted with viruses circulating in domestic poultry, but it inefficiently replicates and transmits in avian hosts. Our findings demonstrate that H12N8 AIV has emerged in domestic poultry, emphasizing the importance of active surveillance of AIVs in both wild and domestic birds. Full article

This study aims to understand the spatial variability of soil nutrients in red-bed regions and identify the environmental factors driving their distribution. We analyzed the spatial distribution and key drivers of pH, soil organic matter, nitrogen, phosphorus, potassium, and their available forms across forestland, cropland, grassland, and bare land in Nanxiong Basin, South China, using principal component analysis, semivariogram analysis, and ordinary Kriging interpolation. Soil organic matter and total nitrogen exhibited moderate variability (CV = 28.64% and 29.81%) driven by topography and vegetation. Available nitrogen showed low variability (CV = 17.91%), reflecting regulation by large-scale ecological processes. In contrast, available phosphorus demonstrated the highest variability (CV = 37.14%), shaped by localized fertilization and erosion. Unique interactions between topography and hydrology were governed by nutrient patterns in grasslands, while anthropogenic homogenization dominated croplands. Semivariogram analysis revealed strong spatial dependency for phosphorus, reflecting natural regulation, while weak dependency for potassium highlighted human-induced randomness. This study also identified capillary water capacity as a key driver in grassland nutrient cycling, adding to our knowledge of soil–water–plant interactions. Together, these findings provide a scientific basis for integrating precision agriculture and ecosystem-based strategies to enhance soil fertility and resilience in red-bed regions under diverse land use conditions. Full article

A comprehensive evaluation of the variations in carbon use efficiency (CUE) and water use efficiency (WUE) in the Nanling Mountains Region (NMR) is crucial for gaining insights into the intricate relationships between climate change and ecosystem processes. This study evaluates the spatiotemporal rates of dynamics in CUE, WUE, gross primary productivity (GPP), net primary productivity (NPP), and evapotranspiration (ET) over the period from 2001 to 2023, using remote sensing data and linear regression analysis. Trend analysis, Hurst exponent analysis, and stability analysis were applied to examine the long-term patterns of CUE and WUE, while partial correlation analysis was employed to explore the spatial relationships between these efficiencies and climatic factors. The main findings of the study are as follows: (1) The CUE and WUE of the NMR decreased geographically from 2001 to 2023, and both the CUE and WUE of NMR showed a significant declining trend (p < 0.05) with the CUE decreasing at a rate of 0.0014/a (a: year) and the WUE falling at a rate of 0.0022/a. (2) The average values of the CUE and WUE of the NMR from 2001 to 2023 were 0.47 and 0.82 g C·m⁻²·mm⁻¹, respectively, with a clear geographical difference. (3) The CUE and WUE in the NMR showed widespread degradation trends with some localized improvements, yet sustainability analysis indicates a likely continued decline across most areas, particularly for forests, while grasslands exhibit the greatest resilience. (4) Precipitation had a significantly stronger impact on WUE, while temperature appeared to exert a more substantial effect on CUE, with vegetation types responding differently; notably, shrubland displayed a direct association between CUE and temperature. In summary, multi-source data were employed to comprehensively analyze the spatiotemporal dynamics of CUE and WUE in the NMR over the past 23 years. We also examined the features of their responses to global warming, offering valuable theoretical insights into the carbon and water dynamics within the terrestrial ecosystems of the NMR. Full article

African swine fever virus (ASFV) is a severe threat to the global pig industry, and domestic pigs mostly develop severe clinical manifestations upon viral invasion. Currently, there is no available vaccine against ASFV. Its capsid structural protein p72 is one of the immuno-dominant proteins. In this study, we unexpectedly obtained a p72 mutant protein (p72_∆377–428) which deleted the aa 377–428 within p72 and had stable and high expression in E. coli. Using SWISS-MODEL 1.0 software, the prediction showed that p72_∆377–428 was quite distinct from the wild-type p72 protein in structure. p72_∆377–428 induced stronger antibody production in mice on day 42 and 56 post immunization and could recognize ASFV-infected swine sera. p72_∆377–428 reduced IFN-γ production in the splenocytes from p72_∆377–428-immunized mice and p72_∆377–428-treated swine macrophages compared to p72. p72_∆377–428 also decreased the production of pro-inflammatory cytokine genes, including IL-1β, IL-6, and IL-12, compared to p72 in mice. Further, we found that p72_∆377–428 reduced the induction of pro-inflammatory cytokine genes by inhibiting AKT phosphorylation and HIF1α expression. Taken together, these findings have implications for immunological function and the corresponding mechanism of ASFV p72, and our study indicates that p72_∆377–428 could serve as a novel candidate for ASFV vaccines and diagnostic reagents. Full article

Influenza A viruses (IAVs) are highly contagious pathogens that cause zoonotic disease with limited availability of antiviral therapies, presenting ongoing challenges to both public health and the livestock industry. Unveiling host proteins that are crucial to the IAV life cycle can help clarify mechanisms of viral replication and identify potential targets for developing alternative host-directed therapies. Using a four-dimensional (4D), label-free methodology coupled with bioinformatics analysis, we analyzed the expression patterns of cellular proteins that changed following H9N2 virus infection. Compared to the control group, the H9N2 infected group displayed 732 differentially expressed proteins (DEPs), with 298 proteins showing upregulation and 434 proteins showing downregulation. Gene Ontology (GO) functional analysis showed that DEPs were catalog in 11 biological processes, three cellular components, and eight molecular functions. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that DEPs were involved in processes including cytokine signaling pathways induced by virus infection and protein digestion and absorption. Proteins including TP53, DDX58, and STAT3 were among the top hub proteins in the protein–protein interaction (PPI) analysis, suggesting that these signaling cascades could be essential for the propagation of IAVs. Furthermore, the host protein SNAPIN was chosen to ascertain the accuracy of expression changes identified through a proteomic analysis. The results indicated that SNAPIN was downregulated following infection with IAVs both in vitro and in vivo, which is consistent with the proteomics results, suggesting that SNAPIN may serve as a key regulatory factor in the viral life cycle of IAVs. Our research delineates an extensive interaction map of IAV infection within the A549 cells, facilitating the discovery of pivotal proteins that contribute to the virus’s propagation, potentially offering target candidates to screen for antiviral therapeutics. Full article