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.

Integrated medical curriculum is an important direction for the development of medical education. While integrated theoretical courses have been practiced for many years, integrated experiments are still in the exploratory stage. Taking the integrated experiments of medical microbiology and immunology in Xi'an Jiaotong University as an example, this article introduces the design concept, implementation details, effectiveness evaluation, improvements, and prospects of integrated experiments established based on clinical practice principles, so as to provide a reference for further optimization of integrated experiments in the future.

Objectives:To investigate the prognostic value of the CHA2DS2-VASc and R2CHA2DS2-VASc scores in patients with atrial fibrillation(AF)and heart failure(HF).Methods:Patients with AF and HF from hospitals diagnosed by the Heart Failure Center in Guangdong Province between January 2017 and December 2021 were selected.Major adverse cardiovascular events(MACE)were used as the follow-up endpoint.Statistical methods such as the area under the receiver operating characteristic(ROC)curve(AUC),net reclassification index(NRI),and integrated discrimination improvement(IDI)were applied to evaluate the predictive value of the CHA2DS2-VASc and R2CHA2DS2-VASc scores in patients with AF and HF.Results:A total of 1 839 patients were enrolled in this study,comprising 703 patients in the MACE group and 1 136 patients in the non-MACE group.Compared with the non-MACE group,the MACE group exhibited significantly advanced age,higher prevalence of New York Heart Association class Ⅳ and coronary artery disease,lower diastolic blood pressure and estimated glomerular filtration rate levels,and elevated serum N-terminal pro-B-type natriuretic peptide concentrations(all P<0.05).Additionally,significantly lower proportions of patients in the MACE group received angiotensin-converting enzyme inhibitors/angiotensin receptor blockers/angiotensin receptor-neprilysin inhibitors,beta-blockers,mineralocorticoid receptor antagonists,or anticoagulant therapy(all P<0.05).Multivariable logistic regression analysis revealed that each 1-point increment in both CHA2DS2-VASc and R2CHA2DS2-VASc scores was associated with approximately 10%increased risk of MACE.ROC curve analysis demonstrated that the AUC values for predicting MACE in AF patients with HF were 0.555(95%CI:0.528-0.582,P<0.001)for CHA2DS2-VASc and 0.576(95%CI:0.549-0.608,P<0.001)for R2CHA2DS2-VASc,indicating marginally superior discriminatory capacity of the R2CHA2DS2-VASc score.Delong's test confirmed statistically significant differences between the two scoring systems(P=0.001).The R2CHA2DS2-VASc score demonstrated a NRI of 0.259(95%CI:0.166-0.352,P<0.001)and an IDI of 0.007(95%CI:0.005-0.010,P<0.001)compared with the conventional CHA2DS2-VASc score.Although the R2CHA2DS2-VASc score exhibited slightly better predictive accuracy and outcome discrimination capacity than the original scoring system,both scores demonstrated suboptimal clinical predictive performance.Conclusions:Both the R2CHA2DS2-VASc and CHA2DS2-VASc scores show suboptimal performance for predicting the risk of MACE in patients with AF and HF,and the predicting performance of R2CHA2DS2-VASc score is marginally superior to CHA2DS2-VASc score in this patient cohort.

The incidence of digestive system diseases is high. So digestive system pathology is widely concerned. In the past 10 years, Chinese pathologists insist on hard work and have made significant progress. This article reviews the research and practice progress in digestive system tumors and non-tumors in the past 10 years, including the establishment of diagnostic criteria for gastrointestinal tract, hepatobiliary and pancreatic diseases, the establishment and classification of new diseases with special morphology, the classification and standard update of gastrointestinal and pancreatic neuroendocrine tumors, the progress of molecular pathology, and non-tumor lesions of the digestive system. The future development trend of digestive system pathology is also prospected.

A mounting body of research suggests that circRNAs significantly contribute to the develop-ment of myocardial fibrosis.The microarray results of human circular RNA expression profile indicated that circHERC4_041 expression increased in the myocardium of patients with heart failure,RT-qPCR a-nalysis confirmed that the myocardial expression level of circHERC4_041 in individuals with heart failure were considerably elevated compared to that in healthy organ donors.Fluorescence in situ hybridization(FISH)confirmed that circHERC4_041 was abundant in the cytoplasm of human cardiomyocyte AC16.Overexpression of circHERC4_041 in mouse myocardial fibroblasts(mCFs)mediated by adenovirus in-hibited the expression of fibrosis-related proteins in mCFs.Experiments involving cell proliferation,wound healing,and Transwell assays demonstrated that overexpression of circHERC4_041 suppressed the growth and mobility of mCFs(P＜0.001).Sequence analysis results suggested that circHERC4_041 con-tains potential ribosome entry sequence(IRES)and open reading frame(ORF).Western blot confirmed that circHERC4_041 could translate the 516 amino acid HERC4-516aa protein,which was mainly located in the cytoplasm of the cell.Cell functional experiments confirmed that circHERC4_041 inhibited the fi-brotic phenotype of mCFs by specifically translating HERC4-516aa(P＜0.05).The specific interaction between HERC4-516aa and transglutaminase 2(TGM2)was confirmed by IP-MS screening and Co-IP i-dentification.Further results found that the degradation of TGM2 was promoted through proteasome path-way.The overexpression of TGM2 in mCFs facilitated by adenoviral vectors could counteract the suppres-sive effects of HERC4-516aa on the fibrotic phenotype of mCFs.Therefore,this study confirmed that the HERC4-516aa protein translated by circHERC4_041 can specifically bind to TGM2 to inhibit the fibrotic phenotype of myocardial fibroblasts.

Objective:To evaluate the value of deep-inhaled breath-hold (DIBH)-30s scanning with total-body PET/CT under half-dose injection mode in improving the poor alignment of thoracic and upper abdominal tumors.Methods:Forty-six patients (28 males, 18 females, age (57.3±11.4) years) who underwent half-dose 18F-FDG total-body DIBH-30s PET/CT examination because of suspect or confirmed thoracic and upper abdominal tumors in Sun Yat-Sen University Cancer Center between October 2022 and February 2023 were analyzed retrospectively. SUV, standard deviation (SD) and signal-to-noise ratio (SNR) of the liver and mediastinal blood pool in free breath (FB)-8min, FB-30s and DIBH-30s PET images were measured; SUV of lesions, metabolic tumor volume (MTV) and tumor-to-background ratio (TBR) in DIBH-30s and FB-8min images were also measured; maximum diameter of contraposition offset and offset rate in coronal, transverse and sagittal directions of lesions in DIBH-30s and FB-8min images were calculated. Five-point Likert scale was used to score the overall image quality, image noise level and diagnostic confidence of fused images. Kruskal-Wallis rank sum test, Nemenyi test or Mann-Whitney U test was used to compare the parameters of different groups. Results:Among the 46 patients, 38 successfully completed breath-holding collection, and 80 lesions were detected, including 37 in the lungs and 43 in the livers. The liver SUV max (3.40(3.15, 3.63), 3.44(3.06, 3.70)) and SD (0.36(0.32, 0.41), 0.35(0.30, 0.40)) in DIBH-30s group and FB-30s group were higher than those (SUV max: 2.73(2.45, 2.92), SD: 0.15(0.13, 0.17)) in FB-8min group ( H values: 49.79, 85.27, χ2 values: 3.26-3.65, all P<0.001). The SUV max and the SD of mediastinal blood pool in DIBH-30s group and FB-30s group were also higher ( H values: 9.31, 59.73, χ2 values: 2.13-2.75, all P<0.01), while SNR liver and SNR med in those 2 groups were lower ( H values: 87.90, 54.11, χ2 values: 3.36-5.47, all P<0.001). The image noise scores of DIBH-30s group and FB-30s group were lower than the score of FB-8min group (3(3, 3) vs 3(3, 4) vs 5(5, 5); H=93.02, χ2 values: 2.13, 2.23, all P<0.001). The overall image quality score and diagnostic confidence score of DIBH-30s group were higher than those of FB-30s group and FB-8min group ( H values: 70.13, 24.22, χ2 values: 2.11-2.48, all P<0.001). The SUV and TBR of lesions in DIBH-30s group were higher than those of FB-8min group ( Z values: from -3.82 to -2.44, all P<0.05), while the MTV, contraposition offset and offset rate were lower than those of FB-8min group ( Z values: from -6.20 to -3.18, all P<0.001). Conclusions:DIBH-30s scanning with total-body PET/CT can make the focus alignment more accurate, which is suitable for short-time collection or low drug administration activity. It has a unique value in improving the poor focus alignment of chest and upper abdomen tumors.

Objective:To explore differences in the efficacy and safety of ruxolitinib in patients with myelofibrosis by age and to identify prognostic factors by analyzing clinical features and characteristics of chromosomes and gene mutations.Methods:This study retrospectively analyzed 188 patients with myelofibrosis who received ruxolitinib in the Department of Hematology, Qilu Hospital, Shandong University from January 1, 2017, to July 1, 2024. According to age at diagnosis, the patients were divided into the middle-aged group (≤55 years), young elderly group (56-65 years), and elderly group (>65 years). Clinical features, the characteristics of chromosomes and gene mutations, and the efficacy and safety of ruxolitinib treatment were compared across the three age groups. Independent factors influencing overall survival were identified through Cox proportional risk regression analysis.Results:Before treatment, the elderly group had more underlying comorbidities, a heavier symptom burden, higher leukocyte count, higher proportion and frequency of JAK2 mutations, and lower proportion of CALR mutations. The incidence of nondriver gene mutations was significantly higher in the young elderly group. After ruxolitinib treatment, the degree of reduction in spleen size did not differ significantly among the three groups. The length of the palpable spleen below the left costal margin reduced by more than 50% from baseline in 50.9% (27/53) of the patients in the middle-aged group, 43.5% (27/62) in the young elderly group, and 45.5% (20/44) in the elderly group ( P=0.720). No significant difference was observed among the three groups in the degree of reduction in Myeloproliferative Neoplasm Symptom Assessment Form (10-item version) score ( P=0.153), with a reduction in total symptom score by more than 50% achieved by 54.0% (27/50), 60.3% (41/68), and 66.7% (34/51) of the patients from the three groups, respectively ( P=0.429). The most common hematological adverse events were anemia and thrombocytopenia, while the most common nonhematological adverse events were electrolyte disturbance, elevated transaminase activity, and pulmonary infection. Multivariate analysis indicated that in ruxolitinib-treated patients with myelofibrosis, poor overall survival was independently predicted by increased age, reduced hemoglobin, percentage of bone marrow blasts ≥ 1%, absence of JAK2 mutations, chromosomal abnormalities, ≥2 high-molecular-risk mutations, and TP53 mutations. Conclusions:Patients with myelofibrosis stratified by age exhibited heterogeneous clinical features and gene mutation profiles but similar efficacy of ruxolitinib treatment and occurrence of adverse events.

Integrated medical curriculum is an important direction for the development of medical education. While integrated theoretical courses have been practiced for many years, integrated experiments are still in the exploratory stage. Taking the integrated experiments of medical microbiology and immunology in Xi'an Jiaotong University as an example, this article introduces the design concept, implementation details, effectiveness evaluation, improvements, and prospects of integrated experiments established based on clinical practice principles, so as to provide a reference for further optimization of integrated experiments in the future.

The incidence of digestive system diseases is high. So digestive system pathology is widely concerned. In the past 10 years, Chinese pathologists insist on hard work and have made significant progress. This article reviews the research and practice progress in digestive system tumors and non-tumors in the past 10 years, including the establishment of diagnostic criteria for gastrointestinal tract, hepatobiliary and pancreatic diseases, the establishment and classification of new diseases with special morphology, the classification and standard update of gastrointestinal and pancreatic neuroendocrine tumors, the progress of molecular pathology, and non-tumor lesions of the digestive system. The future development trend of digestive system pathology is also prospected.

Objective To understand the current situation of healthcare-associated infection(HAI)in China,pro-vide data support and decision-making basis for formulating scientific and effective strategies for HAI prevention and control.Methods A nationwide cross-sectional survey on HAI was conducted among various types and levels of medical institutions in China according to a unified protocol of bedside surveys and case investigations.Results In 2024,a total of 5 736 medical institutions and 2 751 765 patients were surveyed.Among them,34 889 HAI cases were identified,with a prevalence rate of 1.27％.The number of HAI episodes was 38 032,and case prevalence rate was 1.38％.The prevalence rate of HAI in medical institutions in different regions of China ranged from 0.66％to 2.35％.Among medical institutions of different scales,those with a bed capacity of ≥900 had the high-est incidence of HAI,reaching 1.65％.The most common infection site was the lower respiratory tract(44.66％),followed by the urinary tract(12.94％),surgical site(9.32％),upper respiratory tract(7.02％),and bloodstream infection(5.78％).The top 3 departments with the highest HAI rates were the general intensive care unit(10.02％),department of neurosurgery(5.51％),and department(group)of hematology(5.34％).A total of 23 238 strains of HAI pathogens were detected,with 10 714 strains(46.10％)from lower respiratory tract speci-mens.The top 5 detected strains were Klebsiella pneumoniae(14.76％),Pseudomonas aeruginosa(13.33％),Escherichia coli(12.79％),Acinetobacter baumannii(9.23％),and Staphylococcus aureus(7.88％).231 944 pa-tients underwent class Ⅰ incision surgery were monitored,with 1 647 cases experienced surgical site infection,and the prevalence rate of surgical site infection was 0.71％.The number of patients who should undergo pathogen de-tection(patients receiving therapeutic and therapeutic combined prophylactic antimicrobial agents)was 715 179,while the actual number was 480 492,with a pathogen detection rate of 67.18％.425 225 patients received patho-genic detection before treatment,with a detection rate of 59.46％.Conclusion The overall HAI prevalence in Chi-na is lower,showing disparities among medical institutions of different regions and scales.Therefore,precise imple-mentation of measures is necessary for HAI prevention and control,with a focus on high-risk institutions and high-risk departments,key areas,and critical procedures.All levels of medical institutions should continuously reduce the incidence of HAI by strengthening monitoring,standardizing the use of antimicrobial agents,and reinforcing basic HAI prevention and control measures.