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.

Objective To investigate the role and potential mechanism of secreted phosphoprotein 1 (SPP1)⁺ macrophages in the formation of chronic renal allograft fibrosis. Methods The expression features of SPP1⁺ macrophages in renal allografts of chronic allograft dysfunction (CAD) patients were analyzed based on single-cell transcriptome data of renal tissues from patients with CAD. Transcription factor VIPER analysis and DoRothEA transcription factor activity analysis were performed on the single-cell transcriptome data. Renal tissue samples were collected from kidney transplant recipients, including the CAD group (n=5) and the non-renal allograft fibrosis group (CTL group, n=5). A mouse model of chronic allograft rejection was established and divided into the allogeneic kidney transplantation group (CAD group, n=3) and the syngeneic kidney transplantation group (SYN group, n=3). Hematoxylin-eosin staining was used to detect renal tissue injury in mice, and Masson staining was used to detect renal tissue fibrosis. Immunofluorescence staining was performed to detect SPP1 expression in renal tissues of transplant recipients and mouse renal allografts. Bone marrow-derived macrophages (BMDMs) were extracted from mice and subjected to hypoxia stimulation. The expression of hypoxia-inducible factor (HIF)-1α and SPP1 was detected by Western blot, and SPP1 expression was detected by flow cytometry. BMDMs were transfected with HIF-1α overexpression plasmid and HIF-1α small interfering RNA (siRNA) followed by hypoxia intervention, and the expression of HIF-1α and SPP1 was detected by Western blot. Mouse aortic endothelial cells (MAECs) were co-cultured with the supernatant of BMDMs, and the expression of endothelial-mesenchymal transition (EndMT)-related markers was detected by Western blot and immunofluorescence. Results Single-cell transcriptome analysis showed that the proportion of SPP1⁺ macrophages in renal allograft tissues was significantly higher in the CAD group than in the CTL group (P<0.05). The renal injury score and the percentage of interstitial fibrotic area in the CAD group were significantly higher than those in the SYN group (both P<0.05). Immunofluorescence staining showed that the proportion of SPP1⁺ macrophages was increased in the CAD group compared with the CTL group, and also increased in the CAD group compared with the SYN group (both P<0.05). VIPER analysis and DoRothEA transcription factor activity analysis revealed activation of the hypoxia pathway and upregulated expression of transcription factors such as HIF-1α in SPP1⁺ macrophages. SPP1 expression was elevated in BMDMs under hypoxic conditions. Knockdown of HIF-1α inhibited hypoxia-induced SPP1 protein expression, whereas overexpression of HIF-1α upregulated SPP1 protein levels. After co-culture of hypoxia-induced BMDMs with MAECs, the expression levels of EndMT-related markers were increased. Conclusions SPP1⁺ macrophages differentiated under hypoxia are significantly infiltrated in the formation of chronic renal allograft fibrosis, and may promote renal allograft fibrosis by inducing EndMT in renal vascular endothelial cells.

OBJECTIVE To investigate the effectiveness of different bacterial cleaning methods and their effects on the general condition,nasal mucosal and systemic inflammation of mice.METHODS A total of 44 mice were randomly divided into six groups:4-antibiotic per os group(4ABX po)with 7 mice,5-antibiotic oral gavage group(5ABX og)with 8 mice,5-antibiotic intranasal group(5ABX in)with 8 mice,and each of their control groups with 7 mice.Body weight,water intake,and peripheral blood routine test of mice were measured.Bacterial culture of nasal lavage fluid(NLF)was performed;mRNA level of inflammatory mediators and histopathological analysis were conducted with mouse nasal mucosa.RESULTS Bacteria were cultured from all control groups,while Bacteria were cultured from all control groups,while one mouse in the 4ABX po group,three mice in the 5ABX og group,and two mice in the 5ABX in group showed no bacterial growth.The number of goblet cells in the nasal mucosa significantly increased in the 5ABX og group compared with its control group(P<0.05).The 5ABX in group exhibited significantly higher counts of peripheral blood lymphocytes and hemoglobin levels,as well as greater nasal mucosal thickness compared with its control group,with a notable decrease in goblet cells(P<0.05).No statistical differences were observed in body weight or the mRNA expression of nasal mucosal inflammatory mediators.CONCLUSION Different combinations of antibiotics and administration routes have varying effects on nasal bacteria,systemic and nasal mucosal inflammation in mice.Therefore,choosing appropriate protocols is crucial for the progression of subsequent research.

The research investigated the characteristics of lymphocyte subsets in peripheral blood of children with mycoplasma pneumoniae pneumonia in different infection states. The retrospective cross-sectional study selected 194 children with pneumonia from October 2023 to January 2024 in Zhongnan Hospital of Wuhan University as the study objects, patients aged 7 months to 13 years old, including 91 female children and 103 male children. According to the types of pathogens, the children with pneumonia were divided into single MP infection group (80 cases), non-MP infection group (29 cases) and mixed pathogen infection group (85 cases). According to the mutation of MP23S rRNA gene, the MPP children were divided into drug-resistance group (112 cases) and non-drug-resistance group (53 cases). According to the results of bronchoscopy and imaging, the MPP children were divided into severe group (35 cases) and mild group (130 cases). Pathogen infection, the percentage and absolute count of lymphocyte subsets in peripheral blood, hypersensitive CRP, interferon-γ, tumor necrosis factor-α, interleukin-10, interleukin-4, interleukin-6 and interleukin-2 in each group were analyzed retrospectively. The levels of the test items in each group were compared. The value of peripheral blood lymphocyte subsets in the diagnosis of MPP in children was evaluated by ROC curve. The results showed that the co-infection rate of MPP children was 51.51% (85/165). Streptococcus pneumoniae was the most common co-infection (39/85, 45.88%), followed by Haemophilus influenzae (26/85, 30.89%). The mutation rate of MP resistance gene was 67.88% (112/165) in MPP children tested for tNGS in bronchoalveolar lavage fluid. The absolute counts (cells/μl) of CD3 +, CD3 +CD4 +, CD3 +CD8 +, CD3 -CD19 +, CD3 -CD16 +CD56 +and CD3 +CD16 +CD56 + in the simple MP group (1 164, 612, 415, 242, 168, 50) and the mixed pathogen group (1 285, 694, 457, 313, 176, 52) were significantly lower than those in the non-MP group (2 092, 1 037, 660, 541, 295, 86) ( P<0.05). There was no significant difference between drug-resistant group and non-drug-resistant group ( P>0.05). The CD3 +CD4 +% (34.91) and the absolute counts of CD3 -CD16 +CD56 + (148 cells/μl) in severe group was significantly lower than that in mild group (37.91, 187 cells/μl), and CD3 -CD19 +% (19.48) was significantly higher than that in mild group (16.33) ( P<0.05). The median values (cells/μl) of CD3 + (1 093, 925), CD3 +CD4 + (576, 543), CD3 +CD8 + (401, 356), CD3 -CD19 + (238, 234) and CD3 -CD16 +CD56 + (181, 153) in MPP children aged 4 to 8 years and 9 to 12 years were lower than the reference range in corresponding age. ROC curve analysis showed that the AUC of peripheral blood lymphocyte subsets for MPP diagnosis was 0.813, and the sensitivity was 79.3%, the specificity was 75%. In conclusion, the co-infection rate of MPP children was higher than single MP infection. The characteristics of peripheral blood lymphocyte subsets in children with pneumonia were that the absolute count test value of MPP children was significantly lower than that of non-MP infection, and there are differences between MPP children clinical types.

To study the differences in transcript levels among different organs of Spatholobus suberectus and to explore the genes encoding enzymes related to the catechin biosynthesis pathway, this study utilized the genome and full-length transcriptome data of S. suberectus as references. Transcriptome sequencing and bioinformatics analysis were performed on five different organs of S. suberectus-roots, stems, leaves, flowers, and fruits-using the Illumina NovaSeq 6000 platform. A total of 115.28 Gb of clean data were obtained, with GC content values ranging from 45.19% to 47.54%, Q20 bases at 94.17% and above, and an overall comparison rate with the reference genome around 90%. In comparisons between the stem and root, stem and leaf, stem and flower, and stem and fruit, 10 666, 9 674, 9 320, and 5 896 differentially expressed genes(DEGs) were identified, respectively. The lowest number of DEGs was found in the stem and root comparison group. KEGG enrichment analysis revealed that the DEGs were mainly concentrated in the pathways of phytohormone signaling, phenylalanine biosynthesis, etc. A total of 39 genes were annotated in the catechin biosynthesis pathway, with at least one highly expressed gene found in all organs. Among these, PAL1, PAL2, C4H1, C4H3, 4CL1, 4CL2, and DFR2 showed high expression in the stems, suggesting that they may play important roles in the biosynthesis of flavonoids in S. suberectus. This study aims to provide important information for the in-depth exploration of the regulation of catechin biosynthesis in S. suberectus through transcriptome analysis of its different organs and to provide a reference for the further realization of S. suberectus varietal improvement and molecular breeding.
Catechin/biosynthesis* ; Gene Expression Profiling ; Gene Expression Regulation, Plant ; Plant Proteins/metabolism* ; Fabaceae/metabolism* ; Transcriptome ; Flowers/metabolism* ; Plant Stems/metabolism* ; Plant Leaves/metabolism* ; Plant Roots/metabolism* ; Fruit/metabolism*

The research investigated the characteristics of lymphocyte subsets in peripheral blood of children with mycoplasma pneumoniae pneumonia in different infection states. The retrospective cross-sectional study selected 194 children with pneumonia from October 2023 to January 2024 in Zhongnan Hospital of Wuhan University as the study objects, patients aged 7 months to 13 years old, including 91 female children and 103 male children. According to the types of pathogens, the children with pneumonia were divided into single MP infection group (80 cases), non-MP infection group (29 cases) and mixed pathogen infection group (85 cases). According to the mutation of MP23S rRNA gene, the MPP children were divided into drug-resistance group (112 cases) and non-drug-resistance group (53 cases). According to the results of bronchoscopy and imaging, the MPP children were divided into severe group (35 cases) and mild group (130 cases). Pathogen infection, the percentage and absolute count of lymphocyte subsets in peripheral blood, hypersensitive CRP, interferon-γ, tumor necrosis factor-α, interleukin-10, interleukin-4, interleukin-6 and interleukin-2 in each group were analyzed retrospectively. The levels of the test items in each group were compared. The value of peripheral blood lymphocyte subsets in the diagnosis of MPP in children was evaluated by ROC curve. The results showed that the co-infection rate of MPP children was 51.51% (85/165). Streptococcus pneumoniae was the most common co-infection (39/85, 45.88%), followed by Haemophilus influenzae (26/85, 30.89%). The mutation rate of MP resistance gene was 67.88% (112/165) in MPP children tested for tNGS in bronchoalveolar lavage fluid. The absolute counts (cells/μl) of CD3 +, CD3 +CD4 +, CD3 +CD8 +, CD3 -CD19 +, CD3 -CD16 +CD56 +and CD3 +CD16 +CD56 + in the simple MP group (1 164, 612, 415, 242, 168, 50) and the mixed pathogen group (1 285, 694, 457, 313, 176, 52) were significantly lower than those in the non-MP group (2 092, 1 037, 660, 541, 295, 86) ( P<0.05). There was no significant difference between drug-resistant group and non-drug-resistant group ( P>0.05). The CD3 +CD4 +% (34.91) and the absolute counts of CD3 -CD16 +CD56 + (148 cells/μl) in severe group was significantly lower than that in mild group (37.91, 187 cells/μl), and CD3 -CD19 +% (19.48) was significantly higher than that in mild group (16.33) ( P<0.05). The median values (cells/μl) of CD3 + (1 093, 925), CD3 +CD4 + (576, 543), CD3 +CD8 + (401, 356), CD3 -CD19 + (238, 234) and CD3 -CD16 +CD56 + (181, 153) in MPP children aged 4 to 8 years and 9 to 12 years were lower than the reference range in corresponding age. ROC curve analysis showed that the AUC of peripheral blood lymphocyte subsets for MPP diagnosis was 0.813, and the sensitivity was 79.3%, the specificity was 75%. In conclusion, the co-infection rate of MPP children was higher than single MP infection. The characteristics of peripheral blood lymphocyte subsets in children with pneumonia were that the absolute count test value of MPP children was significantly lower than that of non-MP infection, and there are differences between MPP children clinical types.

In August 2021, three students with diarrhea from the same school visited a local hospital in the S district of Beijing. An epidemic investigation showed that there were more students with diarrhea in the same school and they had one meal together. Campylobacter jejuni was isolated from both patients with diarrhea and asymptomatic food handlers; however, the latter also carried Campylobacter coli. Phylogenomic analysis showed that there was a campylobacteriosis outbreak among the students, and the asymptomatic food handler may have been the source of the infection. Routine inspection and surveillance for Campylobacter is needed for the food producing staff, particularly those cooking in the cafeteria in schools or other public food services.
Humans ; Campylobacter Infections/epidemiology* ; Gastroenteritis ; Diarrhea ; Campylobacter ; Disease Outbreaks

Objective: To investigate the risk factors for the development of deep infiltration in early colorectal tumors (ECT) and to construct a prediction model to predict the development of deep infiltration in patients with ECT. Methods: The clinicopathological data of ECT patients who underwent endoscopic treatment or surgical treatment at the Cancer Hospital, Chinese Academy of Medical Sciences from August 2010 to December 2020 were retrospectively analyzed. The independent risk factors were analyzed by multifactorial regression analysis, and the prediction models were constructed and validated by nomogram. Results: Among the 717 ECT patients, 590 patients were divided in the within superficial infiltration 1 (SM1) group (infiltration depth within SM1) and 127 patients in the exceeding SM1 group (infiltration depth more than SM1). There were no statistically significant differences in gender, age, and lesion location between the two groups (P>0.05). The statistically significant differences were observed in tumor morphological staging, preoperative endoscopic assessment performance, vascular tumor emboli and nerve infiltration, and degree of tumor differentiation (P<0.05). Multivariate regression analysis showed that only erosion or rupture (OR=4.028, 95% CI: 1.468, 11.050, P=0.007), localized depression (OR=3.105, 95% CI: 1.584, 6.088, P=0.001), infiltrative JNET staging (OR=5.622, 95% CI: 3.029, 10.434, P<0.001), and infiltrative Pit pattern (OR=2.722, 95% CI: 1.347, 5.702, P=0.006) were independent risk factors for the development of deep submucosal infiltration in ECT. Nomogram was constructed with the included independent risk factors, and the nomogram was well distinguished and calibrated in predicting the occurrence of deep submucosal infiltration in ECT, with a C-index and area under the curve of 0.920 (95% CI: 0.811, 0.929). Conclusion: The nomogram prediction model constructed based on only erosion or rupture, local depression, infiltrative JNET typing, and infiltrative Pit pattern has a good predictive efficacy in the occurrence of deep submucosal infiltration in ECT.
Humans ; Retrospective Studies ; Colorectal Neoplasms/pathology* ; Nomograms ; Neoplasm Staging ; Risk Factors

1-Deoxy-D-xylulose-5-phosphate synthase (DXS), the first key enzyme in 2-methyl-D-erythritol-4-phosphate (MEP) pathway, catalyzes the condensation of glyceraldehyde-3-phosphate with pyruvate to 1-deoxy-xylose-5-phosphate (DXP). In this study, PgDXS1, PgDXS2, and PgDXS3 genes were cloned from the root of Platycodon grandiflorum (P. grandiflorum). The open reading frame (ORF) of PgDXS1, PgDXS2, and PgDXS3 were 2 160, 2 208, and 2 151 bp in full length, encoding 719, 735, and 716 amino acids, respectively. Homologous alignment results showed a high identity of PgDXSs with DXS in Hevea brasiliensis, Datura stramonium and Stevia rebaudiana. The recombinant expression plasmids of pET-28a-PgDXSs were constructed and transformed into Escherichia coli (E. coli) BL21 (DE3) cells, and the induced proteins were successfully expressed. Subcellular localization results showed that PgDXS1 and PgDXS2 were mainly located in chloroplasts, and PgDXS3 was located in chloroplasts, nucleus and cytoplasm. The expression of three DXS genes in different tissues of two producing areas of P. grandiflorum were assayed via real-time fluorescence quantitative PCR, and the results showed that all of them were highly expressed in leaves of P. grandiflorum from Taihe. Under methyl jasmonate (MeJA) treatment, the expression levels of three PgDXS genes showed a trend of first decreasing and then increasing at different time points (3 - 48 h), and the activity of DXS showed a trend of first increasing and then decreasing in three tissues of P. grandiflorum. This study provides a reference for further elucidating the biological function of PgDXS in terpenoid synthesis pathway in P. grandiflorum.