Olfactory receptors (ORs) form the largest superfamily of G protein-coupled receptors (GPCRs). Traditionally recognized for their role in the nasal olfactory epithelium, where they mediate the sense of smell, accumulating evidence has firmly established their ectopic expression in non-olfactory tissues, including the intestine, lungs, and kidneys. The intestine, as the primary site for nutrient digestion and absorption, harbors a highly complex chemical environment. To adapt to this environment, the gut employs a sophisticated network of “chemosensors” to monitor luminal contents and maintain homeostasis. Among these sensors, intestinal ORs have emerged as crucial functional components, serving as a molecular bridge that connects environmental chemical signals—such as food-derived odorants—to specific physiological responses. This discovery has significantly deepened our understanding of how dietary flavors and compounds influence intestinal physiology at the molecular level. This review systematically summarizes the expression profiles, ligand classification, and biological functions of ORs within the gastrointestinal tract. Studies indicate that intestinal ORs exhibit distinct spatial distribution patterns across different gut segments and display cell-type specificity, particularly within enterocytes and enteroendocrine cells. These receptors function as versatile sensors capable of recognizing a wide variety of ligands, including exogenous dietary components, gut microbiota metabolites such as short-chain fatty acids, and endogenous small molecules like azelaic acid. Upon activation by specific ligands, intestinal ORs trigger intracellular signaling cascades, primarily involving the AC-cAMP-PKA pathway or calcium influx channels. A major focus of this review is to elucidate the molecular mechanisms by which these receptors regulate the secretion of gut hormones. Activation of specific ORs in enteroendocrine cells has been shown to stimulate the release of hormones such as glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and serotonin (5-HT), thereby modulating systemic energy metabolism, glucose homeostasis, and gastrointestinal motility. Furthermore, the review addresses the critical roles of ORs in immune regulation and pathology. Evidence suggests that specific ORs contribute to the maintenance of intestinal immune homeostasis and may offer protection against inflammation. Beyond their involvement in inflammatory responses, ORs such as Olfr78 have been shown to regulate the differentiation and function of intestinal endocrine cells. Similarly, Olfr544 has been demonstrated to alleviate intestinal inflammation by remodeling the gut microbiome and metabolome. These findings collectively suggest that specific ORs hold promise as therapeutic targets for mitigating intestinal inflammation and maintaining gut homeostasis. Additionally, the review explores the emerging role of ORs in cancer. Although OR expression is often downregulated in tumor tissues compared to normal mucosa, activation of specific ORs by certain ligands can inhibit tumor cell proliferation and migration and induce apoptosis via pathways such as MEK/ERK and p38 MAPK. Conversely, other receptors, such as OR7C1, may serve as biomarkers for cancer-initiating cells. In conclusion, intestinal ORs represent a vital component of the gut’s sensory network. The review also discusses the translational potential of these findings. By elucidating the precise pairing relationships between dietary components and specific ORs, novel therapeutic strategies could be developed. Intestinal ORs may thus emerge as promising targets for nutritional and pharmacological interventions in metabolic diseases, inflammatory bowel diseases, and malignancies.

Background: Malignant vasovagal syncope (VVS) is characterized by cardiac arrest lasting more than 3 seconds during a syncope episode or head-up tilt test (HUTT). We aim to conduct a risk assessment for potential malignant VVS before the HUTT by using economic, simple and convenient demographic data, in order to prevent adverse outcomes for pediatric VVS.Purpose: To explore the correlation between demographic factors and pediatric malignant VVS, and verify the value of these factors in early risk assessment for malignant VVS before HUTT, so as to optimize test safety and reduce adverse events. Methods: We conducted a retrospective analysis of the clinical data of 3,734 children who were initially diagnosed with VVS due to unexplained syncope and presyncope. Finally, 122 children who met the diagnostic criteria for malignant VVS were included in the malignant VVS group, and 661 children who did not meet the criteria during the same period were matched as the control group. By analyzing demographic data and other factors, we attempted to clarify the association between these factors and malignant VVS. Results: Linear relationship: age and body mass index (BMI) have independent protective effects on malignant VVS. For every 1-year increase in age and every 1 kg/m2 increase in BMI, the risk of malignant VVS decreases by 12% and 9%, respectively. Nonlinear relationship: When the age is <12.9 years old, for every additional year of age, the risk of malignant VVS decreases by 20%. For ages 12.9 years and above, the efficacy is not significant. There is no significant nonlinear relationship between BMI and malignant VVS. Conclusion Age and BMI are independent protective factors for pediatric malignant VVS. Before the age of 12.9 years, the incidence of malignant VVS gradually decreases with the increase in age, and thereafter there is no significant impact.

ObjectiveFlavonoids are clinically significant natural products, yet their oxygen-glycosylation in aqueous environments relies heavily on expensive nucleotide-activated sugar donors such as UDP-glucose. Liquid-liquid phase separation (LLPS) creates specialized, membraneless physicochemical microenvironments capable of modulating enzymatic functions and overcoming mass transfer limitations. This study aims to investigate whether the gut microbiota-derived DgpB/C complex—a multienzyme system traditionally recognized for cleaving stable C-glycosidic bonds and facilitating isomerization—can undergo functional remodeling within phase-separated condensates. Our core objective is to elucidate the role of phase separation in expanding enzymatic catalytic plasticity and to provide a non-canonical, highly cost-effective biocatalytic mechanism for the direct utilization of free sugars in the synthesis of O-glycosylated natural products. MethodsAn artificial phase-separation platform was constructed utilizing the multivalent arginine-glycine-glycine motif (RGG)-repeat domain derived from the Caenorhabditis elegans LAF-1 protein. To ensure precise spatial compartmentalization, the DgpB/C complex was specifically recruited into the RGG condensates via a high-affinity SZ1/SZ2 heterodimerization tag system. Condensate formation and substrate partitioning were visualized using light and confocal fluorescence microscopy. The chemical structures and regioselectivity of the reaction products were rigorously characterized using high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS)/MS systems. Furthermore, molecular docking and 20-ns molecular dynamics (MD) simulations were performed via the Hermite platform and Uni-GBSA pipeline to elucidate the structural and thermodynamic basis underlying the phase-transition-induced functional shift. ResultsWe observed that the condensates formed by RGG proteins selectively recruited and significantly enriched hydrophobic flavonoid substrates. Strikingly, within the LLPS microenvironment, the DgpB/C complex—which typically exhibits only degradative or isomerase activities—underwent a profound functional remodeling, transforming into an efficientO-glycosyltransferase. Diverging from canonical pathways that require high-energy donors, the sequestered DgpB/C complex directly utilized unactivated free glucose to catalyze the formation of new O-glycosidic bonds. This remodeled activity was found to be evolutionarily conserved across DgpB/C homologs from diverse gut microbiota strains, such as P581a and W974-1. LC-MS/MS analysis further revealed that the phase-separated environment reduced the regioselectivity constraints of the enzyme, enabling catalytic action on multiple hydroxyl positions of the flavonoid scaffold. MD simulations further indicated that the low-water-activity microenvironment of the condensates reconfigured the conformational dynamics of the catalytic pocket, favoring a spatial orientation highly conducive to dehydration condensation. ConclusionThis study demonstrates that LLPS drives the functional remodeling of the gut microbiota enzyme DgpB/C through the reconfiguration of the physicochemical microenvironment. These findings challenge traditional perceptions regarding the functional boundaries of metabolic enzymes and reveal a novel biocatalytic pathway that bypasses the requirement for nucleotide-activated sugars. Consequently, this provides a highly promising artificial compartmentalization strategy for the green manufacturing of complex, high-value-added natural products.

Objective To study the inhibitory effect of secondary metabolites of Pseudomonas aeruginosa(PA)on Candida albicans(CA)and to explore some of the mechanisms.Methods PA and CA strains were i-solated from clinical specimens from the hospital.Then,PA strains with inhibitory effects on CA were screened through cross-line test and co-incubation test,and crude extracts of PA secondary metabolites were prepared,and were tested together with pyocyanin,phenazine-1-carboxylic acid,1-hydroxyphenazine,and 3-ox-ododecyl-l-homoserine lactone(3-oxo-HSL).The inhibitory effects of various PA secondary metabolites on CA were determined through minimum inhibitory concentration test,minimum bactericidal concentration test,time-sterilization curve measurement,and XTT method activity measurement test,and some mechanisms by which PA secondary metabolites inhibited CA were explored.Results The strongest inhibitory effect on CA was 1-hydroxyphenazine,and at a concentration of 6.250 μg/mL,the relative activity of CA decreased to 0.00%.Next were pyocyanin and PA crude extract,and the relative fungal activity of CA decreased to 0.00%at concentrations of 200 and 100 μg/mL.1-hydroxyphenazine,pyocyanin,3-oxo-HSL and PA crude extract all had inhibitory effects on the formation of CA hyphae.Reactive oxygen species(ROS)were generated in CA cells treated with 1-hydroxyphenazine,phenazine 1-carboxylic acid,pyocyanin,and PA crude extract,and the highest levels of ROS were induced by pyocyanin and 1-hydroxyphenazine.Conclusion Phenazine secondary metabolites 1-hydroxyphenazine and pyocyanin have significant inhibitory effects on the growth and activity of CA,and both induce the highest amount of ROS.The quorum-sensing signal molecule 3-oxo-HSL have no in-hibitory effect on CA growth,but have a significant inhibitory effect on the formation of fungal hyphae.

Objective To explore the predictive value of automated breast ultrasound(ABUS)features combined with Ki-67 in predicting pathological complete response(pCR)after neoadjuvant chemotherapy(NAC)in triple-negative breast cancer(TNBC).Methods A retrospective analysis was conducted on 127 female TNBC patients treated at Xijing Hospital,Air Force Medical University from March 2019 to December 2023.All patients underwent NAC and surgical treatment after ABUS examination.Based on postoperative pathological results,patients were divided into pCR group(n=60)and non-pathological complete response(npCR)group(n=67).Differences in various parameters before NAC were compared between the two groups.LASSO regression was used to identify independent factors influencing pCR after NAC in TNBC patients,and a predictive model was constructed using multivariate logistic regression.The prediction model was internally validated using the Bootstrap method(1000 resamples).The discriminative ability of the model was evaluated using receiver operating characteristic(ROC)curves,and the area under the curves(AUCs)of different prediction models were compared using De-long's test.The accuracy of the model was assessed using calibration curves,and the clinical benefit of the model was evaluated using clinical decision curve analysis(DCA).Results Significant differences were observed between two groups in terms of age,Ki-67,menopausal status,tumor type,posterior echo,coronal plane convergence sign,coronal plane skip sign,and coronal plane white wall sign before NAC(P<0.05).LASSO regression analysis showed that Ki-67,coronal plane convergence sign,and coronal plane white wall sign were independent influencing factors of pCR after NAC in TNBC patients(P<0.05).The AUC of the multivariate logistic regression model based on Ki-67 was 0.733(95%CI 0.646-0.819),the AUC of ABUS model was 0.777(95%CI 0.695-0.858),and the AUC of ABUS combined with Ki-67 model was 0.816(95%CI 0.741-0.890).De-long's test showed that the AUC of the combined model was higher than those of ABUS feature model and Ki-67 model,with statistically significant differences(P<0.05).There was no significant difference in the AUC between ABUS feature model and Ki-67 model(P=0.40).Hosmer-Lemeshow test indicated that the combined model had a good fit(P=0.304).Internal validation results showed that the combined model had a good stability with a consistency index(C-index)of 0.820(95%CI 0.726-0.879).The calibration curve demonstrated good consistency between the predicted and actual probabilities of the combined prediction model,and the DCA curve indicated that the model had favorable clinical benefit.Conclusion The combined ABUS feature and Ki-67 model can be used to predict the probability of pCR after NAC in TNBC patients,providing a reference for the formulation of clinical treatment plans in TNBC patients.

Objective To investigate the status of population dynamics and distribution changes of Aedes aegypti in Guangdong Province.Methods Continuous monitoring was conducted from May 2018 to July 2024 in Wushi Town and Qishui Town,Leizhou City,Zhanjiang City,Guangdong Province.Additionally,a survey of the distribution of Ae.aegypti along the Leizhou Peninsula coast was carried out.Results The density of Ae.aegypti in Zhanjiang showed a gradual decline from 2018 to 2024.The last detection of adult Ae.aegypti in Wushi Town was in September 2021,and the last larva was found in October 2023.No Ae.aegypti was detected in Qishui Town during surveys from 2021 to 2024.A survey of 18 coastal villages in the Leizhou Peninsula revealed no detections of Ae.aegypti.Conclusions This study provides a basis for understanding the distribution and population density fluctuations of Ae.aegypti,assessing its invasion risk,and scientifically conducting relevant prevention and control efforts.

OBJECTIVE: To evaluate the differential expression of RNA in blood monocytes in patients with Juvenile idiopathic arthritis (JIA) treated with TNF antagonists (TNFi), and to explore the effect and mechanism of gene expression on the efficacy of JIA. METHODS: A total of 29 children with JIA treated with methotrexate (MTX) and TNFi in Guangzhou Women and Children's Medical Center of Guangzhou Medical University from April 2021 to November 2023 were enrolled. After 6 months, the children were divided into two groups according to the treatment effect, i.e., 13 cases in the ineffective group and 16 cases in the effective group, the peripheral blood of the children was collected, the blood mononuclear cells were isolated for transcriptome sequencing, the differentially expressed genes between the groups were analyzed, the signaling pathways and metabolic pathways related to the efficacy of TNFi were analyzed by GO and KEGG enrichment, and the mechanism related to the efficacy of TNFi was explored. This study was approved by Medical Ethics Committee of the Guangzhou Women and Children's Medical Center of Guangzhou Medical University (Ethics No.: 2023-330B00). RESULTS: There was a statistically significant difference in the gender and age distribution between the two groups of children (P < 0.05), while no statistically significant differences were observed in disease duration, rheumatoid antibody levels, or JIA subtypes (P > 0.05). After sequencing data quality control and comparison of reference genomes, a total of 18 523 protein-coding genes were identified in all children's samples. A total of 705 differentially expressed genes (DEGs) were identified between the effective group and the invalid group through differential analysis, of which 579 were up-regulated in the effective group and 126 in the inactive group. GO function and KEGG pathway enrichment analysis showed that DEG was significantly enriched in 55 GO entries and 32 KEGG metabolic pathways, which were mainly related to IL-1β production and regulation, cytokine production and regulation, cytokine-cytokine receptor interaction, immune response regulation, and Toll-like receptor signaling pathway. CONCLUSION DEG between the effective and ineffective groups of TNFi treatment may be involved in the biological processes such as cytokine production and regulation, cytokine-receptor interaction, and immune response regulation, which will be helpful to predict the efficacy and prognosis of TNFi treatment for JIA.
Humans ; Arthritis, Juvenile/blood* ; Female ; Male ; Child ; Methotrexate/therapeutic use* ; Child, Preschool ; Tumor Necrosis Factor-alpha/antagonists & inhibitors* ; Transcriptome ; Adolescent ; RNA/genetics* ; Signal Transduction ; Gene Expression Profiling

The scientific research and innovation capabilities of medical students are intrinsically linked to the sustained and high-quality development of national healthcare initiatives.Cultivating outstanding medi-cal students with independent scientific capabilities and innovative consciousness is a critical component in the education and training of high-level medical professionals.Our investigation revealed that within the imperfections of the cultivating model,some faculty and students at medical schools have an insufficient understanding of scientific research and innovation and lack motivation for engaging in such activities,which hinder the progression of scientific research activities.Consequently,we initiated a teaching practice and exploratory study on the"tutorial system"aimed at fostering medical students'scientific research and innovation abilities.Based on the principle of"research informing teaching,teaching and research advan-cing together,"this study implements a"tutorial system"coordinated by tutors,supplemented by graduate and undergraduate student mentors,to cultivate innovative thinking,stimulate interest in scientific re-search,and enhance practical and research skills among medical students.Through collaborative efforts within"scientific research innovation teams,"various educational methods—including preliminary re-search,in-class and extracurricular activities,intra-group and inter-group interactions,and theoretical and practical applications—are employed to improve and strengthen the cultivation of medical students'scientif-ic research and innovation abilities.This study aims to provide valuable references for optimizing medical education management systems and enhancing the quality of medical student training.

Aim To investigate the neuroprotective effect of dioscin(DIO)on hippocampal neurons(HT22)after oxygen glucose deprivation/reoxygen-ation(OGD/R)and its possible mechanism.Methods HT22 cells were treated with 0,2.5,5,10,20,40,80,160,and 320 mg·L-1DIO for 24 h,and the cell proliferation rate was detected by CCK-8 method.The concentration that was non-toxic to HT 2 2 cells was se-lected for subsequent experiments.After OGD for 2 h,HT22 cells were randomly divided into the OGD/R group,1.25,2.5,and 5 mg·L-1DIO group,and posi-tive control group.HT22 cells were taken as the con-trol group.After drug intervention for 24 h,the cell proliferation rate was detected by CCK-8 method;the LDH release was detected by colorimetry;the cell ap-optosis rate was detected by TUNEL method;the ex-pression of proteins related to PARP-1/AIF pathway and caspase pathway was detected by Western blot.Results DIO intervention significantly upregulated the expression of AIF protein in mitochondria and PAR protein in nucleus of HT22 cells after OGD/R,and sig-nificantly downregulated the release of LDH,neuronal apoptosis rate,total protein expression of AIF and PAR,PARP-1,AIF in nucleus and protein expression of PAR protein in mitochondria,while the expression of Bax and caspase-3 proteins was not significantly differ-ent from that in the OGD/R group.Conclusion DIO can alleviate the apoptosis of HT22 cells induced by OGD/R by regulating the expression and translocation of proteins related to the PARP-1/AIF pathway,thus playing a neuroprotective role.

A pyrene-phenol-based fluorescent probe PyP which showed typical intramolecular charge transfer(ICT)and monomer-excimer activities was synthesized by using pyrene carboxaldehyde hydrazone and 4-tert-butyl-2,6-diformylphenol as the raw materials.The effects of solvents on PyP were studied,and the results showed that the color of protic polar solvents(Ethanol,N,N-dimethylformamide,methanol and H2O)were successfully identified.Based on the solvent polarity-regulated PyP monomer-excimer switching,the rapid and highly sensitive ratiometric probe,"Turn-off"and"Turn-on"multimodal probes were established for detection of trace water content in organic solvents(Dimethyl sulfoxide,N,N-dimethylformamide,ethanol and methanol),with detection limits(3σ/k)of 0.0021％,0.046％,0.062％and 0.024％.The method was successfully used to detect water content in dimethyl sulfoxide,N,N-dimethy lformamide,ethanol and methanol commercial organic solvents,with recoveries ranging from 97.2％to 108.0％.The developed method showed good accuracy and stability,and had good application prospect.