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.

Multidrug-resistant (MDR) bacterial infections have emerged as a serious challenge of global public health crisis. The overuse and misuse of conventional antibiotics have dramatically accelerated the emergence, evolution and worldwide spread of drug-resistant bacterial strains, necessitating urgent exploration of novel antibacterial strategies. Bacteriophages serve as natural bacterial predators offering distinct advantages including high host specificity, autonomous self-replication capabilities and cost-effective large-scale production. However, wild-type phages present significant clinical limitations due to their narrow host ranges, susceptibility to rapid immune clearance and poor penetration of bacterial biofilms, which severely restrict their therapeutic applications. The convergence of synthetic biology, nanotechnology and advanced gene editing technologies has accelerated the development of engineered bacteriophage platforms, providing programmable, scalable and clinically translatable pathways to overcome these inherent biological constraints. Here, we systematically delineate four fundamental strategies for engineered bacteriophage development. Chemical modification utilizes reactive functional groups such as amino, carboxyl and thiol moieties on capsid proteins through esterification, amidation or click chemistry reactions to achieve precise drug conjugation and surface functionalization. In vivo editing encompasses ultraviolet or chemical mutagenesis for random mutation induction, homologous recombination for targeted genetic alterations, recombineering methodologies including electroporation-mediated bacteriophage recombination engineering, and CRISPR-Cas systems for precise genome editing to enable exact genetic reconstruction and host range reprogramming. In vitro synthesis leverages genome engineering platforms where intact phage genomes are transferred into yeast or host bacteria to facilitate highly efficient homologous recombination, enabling large DNA fragment assembly and cross-gene host range expansion without bacterial toxicity constraints. Directed evolution combines artificial selection through mutation library screening with rational design approaches involving chimeric receptor binding protein construction or site-specific mutagenesis, effectively balancing the discovery of unknown adaptive pathways with targeted host specificity modification. Moreover, we comprehensively discuss therapeutic applications across diverse clinical scenarios. Engineered bacteriophage effectively disrupt bacterial biofilms through sophisticated functionalized delivery platforms including nanozyme-conjugated phages, phage-liposome nanoconjugates and bio-responsive hydrogels, demonstrating significantly enhanced bactericidal efficiency compared to unmodified free phages. These bioengineered vectors attenuate bacterial virulence and resensitize pathogens to antibiotics by delivering CRISPR-Cas systems or base editors to disrupt critical virulence factors such as pili, capsule synthesis machineries and quorum sensing systems, or by inactivating antibiotic resistance determinants including beta-lactamase genes. As an intelligent nanomedicine delivery platform, engineered bacteriophage enable precise pathogen elimination an through photocatalytic reactive oxygen species generation, immunomodulatory interventions, or controlled release of antibacterial drugs. Furthermore, oral administration of engineered bacteriophage facilitates microbiota modulation, which selectively eliminate intestinal pathogens while preserve beneficial commensal microbiota, thereby restoring microbial community balance and preventing complications associated with dysbiosis. Finally, we critically analyze persistent challenges including host strain matching complexity, evolution of bacterial resistance mechanisms, pharmacokinetic optimization requirements, optimal administration route selection, large-scale production quality control standards and clinical dosing determination protocols. Through multidisciplinary integration of synthetic biology, infectious disease medicine and immunology, future translational medicine studies of bacteriophage should establish comprehensive technical platforms encompassing rapid phage screening, intelligent rational design, rigorous in vivo evaluation and standardized clinical validation processes, ultimately advancing engineered bacteriophage from laboratory innovations to clinically approved therapeutics for effectively combating MDR bacterial infections.

Nipah virus (NiV) and related viruses form a distinct henipavirus genus within the Paramyxoviridae family. NiV continues to spillover into the humans causing deadly outbreaks with increasing human-bat interaction. NiV encodes the large protein (L) and phosphoprotein (P) to form the viral RNA polymerase machinery. Their sequences show limited homologies to those of non-henipavirus paramyxoviruses. We report two cryo-electron microscopy (cryo-EM) structures of the Nipah virus (NiV) polymerase L-P complex, expressed and purified in either its full-length or truncated form. The structures resolve the RNA-dependent RNA polymerase (RdRp) and polyribonucleotidyl transferase (PRNTase) domains of the L protein, as well as a tetrameric P protein bundle bound to the L-RdRp domain. L-protein C-terminal regions are unresolved, indicating flexibility. Two PRNTase domain zinc-binding sites, conserved in most Mononegavirales, are confirmed essential for NiV polymerase activity. The structures further reveal anchoring of the P protein bundle and P protein X domain (XD) linkers on L, via an interaction pattern distinct among Paramyxoviridae. These interactions facilitate binding of a P protein XD linker in the nucleotide entry channel and distinct positioning of other XD linkers. We show that the disruption of the L-P interactions reduces NiV polymerase activity. The reported structures should facilitate rational antiviral-drug discovery and provide a guide for the functional study of NiV polymerase.
Nipah Virus/chemistry* ; Cryoelectron Microscopy ; Viral Proteins/genetics* ; RNA-Dependent RNA Polymerase/genetics* ; Phosphoproteins/genetics* ; Humans ; Models, Molecular ; Protein Binding

Background: and Purpose Ruptured intracranial aneurysms (RIA) are associated with a mortality rate of up to 40% in the Chinese population, highlighting the critical need for targeted treatment interventions for at-risk individuals. Although the impact of aldehyde dehydrogenase 2 (ALDH2) gene mutations on susceptibility to intracranial aneurysms (IA) is well documented, the potential connection between ALDH2 rs671 single-nucleotide polymorphism (SNP) and RIA remains unexplored. Given the increased prevalence of ALDH2 gene mutations among Chinese Han individuals, it is clinically relevant to investigate the link between ALDH2 rs671 SNP and IA rupture. Methods: A prospective study was conducted on 546 patients diagnosed with IA to investigate the association between ALDH2 rs671 SNP and the risk of IA rupture. Results: The ALDH2 rs671 SNP (ALDH2*2) was significantly more prevalent in patients with unruptured IA (UIA) than in those with RIA (32.56% vs. 18.58%, P=0.004). Multivariate logistic regression analysis revealed that people with the ALDH2 mutation (ALDH2*1/*2 and ALDH2*2/*2 gene type) had a significantly reduced odds ratio (OR=0.49; 95% confidence level [CI] 0.27–0.88; P=0.018) for RIAs. Age-specific subgroup analysis indicated that the ALDH2 mutation provided a stronger protective effect in individuals aged 60 years and above with IA compared to those under 60 years old (OR=0.38 vs. OR=0.52, both P<0.05). Conclusion The incidence of RIA was significantly higher in individuals with a normal ALDH2 gene (ALDH2*1/*1) than in those with an ALDH2 rs671 SNP (ALDH2*1/*2 or ALDH2*2/*2). ALDH2 rs671 SNP may serve as a protective factor against RIA in the Chinese Han population.

Aim To elucidate whether Astragaloside Ⅳcould ameliorate pathological myocardial hypertrophy and fibrosis via the EGR1-SIRT1-PPARα-SCAD signa-ling pathway in TAC mice.Methods After randomi-zing mice into groups,the Sham+AS-Ⅳ group and TAC+AS-Ⅳ group were intragastrically administered 20 mg·kg-1AS-Ⅳ once daily,whereas the Sham+NS group and TAC+NS group were given equivalent saline.Six weeks post-surgery,an evaluation of cardiac function was conducted,heart weight index was compu-ted,morphological alterations in heart were noted,vari-ations in collagen and myocardial hypertrophy indexes were analyzed,ATP content,free fatty acid content,hydroxyproline content,SCAD expression,and enzyme activity were measured,and an initial investigation into the protein expression of EGR1-SIRT1-PPARα-SCAD in myocardial tissues was undertaken.Results After AS-Ⅳ intervention,the heart weight index of TAC mice decreased(P＜0.01),LVAWd,LVAWs,LVPWd and LVPWs values decreased(P＜0.01,P＜0.05),EF％and FS％values increased(all P＜0.01),myocardial hypertrophy markers and collagen area decreased,FFA content,HYP content and collagen expression de-creased(all P＜0.01),SCAD enzyme activity and ex-pression increased(P＜0.01,P＜0.05),and ATP content increased(P＜0.01).The expression of EGR1 protein decreased,and the expression of SIRT1 and PPARα protein increased(all P＜0.01).Conclu-sions AS-Ⅳ may improve fatty acid oxidation via the EGR1-SIRT1-PPARα-SCAD signaling pathway,thereby ameliorating pathological myocardial hypertrophy and fibrosis in TAC model mice.

Objective:To explore the value of using computed tomography(CT)values to distinguish fresh and old fractures vertebral bodies in osteoporotic vertebral compression fractures(OVCF).Methods:Retrospective analysis of clinical data of 101 OVCF patients in our hospital from September 2022 to September 2023.Kappa test for consistency between magnetic resonance imaging(MRI)and vertebral CT values in distinguished fresh or old OVCF.The difference of CT values between fresh,old fractures and adjacent normal vertebral bodies were compared.The diagnostic efficiency was analyed by receiver operating characteristic(ROC)curve.Results:There was a high consistency between vertebral CT values and MRI in the diagnosis of OVCF in fresh and old fractures(Kappa value=0.934).There was a difference in difference of CT values between adjacent normal vertebral bodies and fresh fractures vertebral bodies(P＜0.05).There was a difference in difference of CT values of fresh fractures vertebral bodies and old fractures vertebral bodies(P＜0.05).The ROC curve analysis results showed that,the combined measurement of CT values of fresh and old fractured vertebral bodies has an area under the curve(AUC)of 0.723,which was higher than alone measurement of the CT values of fresh fractured vertebral bodies and old fractured vertebral bodies of 0.536 and 0.610(Z=2.548,2.605,2.841,P＜0.05).Conclusion:CT values of vertebral bodies show high consistency in distinguish fresh and old fractures of OVCF compared to MRI findings,and the diagnostic efficiency of combine detection is relatively high.

Objective:To explore the diagnostic value of conventional computed tomography(CT)combined with enhanced CT scan in bone metastases.Methods:This study was a retrospective observational study,84 suspected bone metastases patients admitted to our hospital from January 2022 to August 2024 were selected,All patients underwent conventional CT and enhanced CT scan and pathological examination,Using pathological examination results as the"gold standard"for diagnosis.The imaging manifestations of bone metastases using conventional CT combined with enhanced CT scan examination were observed;The detection rate and bone metastases types of conventional CT and enhanced CT scan were analyzed;The bone metastases location in different types of malignant tumors were analyzed;The detection results of bone metastases between conventional CT and enhanced CT scan were compared;the diagnostic efficacy of conventional CT and enhanced CT scan alone and in combination for bone metastases were analyzed by Receiver operating characteristic(ROC)curve.Results:The detection rate of osteogenic,osteolytic,cystic and mixed bone metastases by conventional CT combined with enhanced CT scan was supered to that of conventional CT and enhanced CT scan alone(P＜0.05).Bone metastases from lung cancer,breast cancer and other tumors mainly occur in the spine,limbs and ribs,while esophageal cancer,gastric cancer,liver cancer,prostate cancer,thyroid cancer,renal cancer,and nasopharyngeal cancer had relatively fewer bone metastases.The positive detection cases of bone metastases used conventional CT combined with enhanced CT scan were supered to those used conventional CT and enhanced CT scan alone.The sensitivity,specificity and accuracy of conventional CT combined with enhanced CT scan for the diagnosis of bone metastases were 94.00％,94.11％and 94.04％,respectively,and the positive/negative predictive values were 95.91％and 91.42％,respectively.The sensitivity,specificity and accuracy of conventional CT scan were 84.00％,78.78％and 80.95％,respectively,and the positive/negative predictive values were 85.71％and 74.28％,respectively.The sensitivity,specificity and accuracy of enhanced CT were 89.79％,85.71％and 88.09％,respectively.and the positive and negative predictive values were 89.79％and 85.71％,respectively.The diagnostic efficacy of conventional CT combined with enhanced CT scan for bone metastases was significantly better than that of conventional CT and enhanced CT scan alone.Conclusions:Conventional CT combined with enhanced CT scan can significantly improve the diagnostic efficiency of bone metastases,and provide an important basis for clinical treatment.

Objective To investigate the value of MRI of the sternal end of clavicle in bone age assessment in Chinese population,especially its applicability in the determination of criminal responsible age.Methods A total of 431 patients aged from 10.00 to 29.99 years with neck or chest MRI were retrospectively collected.According to the Schmeling grading method,the epiphyseal development of the clavicle MRI was divided into five grades.The consistency of methods was evaluated.The correlation and general descriptive analysis between MRI grades and age was analyzed.The sex difference was analyzed.Curve fitting was used to establish a nonlinear model between age and grades.Results The grades of clavicle MRI showed a significant age-related trend(Figure 2),and the correlation was 0.861(0.887 in males and 0.840 in females).Except for grade 1,there was no significant difference between males and females in other grades.The minimum age of male grade 3 was greater than 14 years old,and the minimum age of female grade 3 was greater than 16 years old.The minimum age in grade 4 and grade 5 was over 18 years old in both sexes.The best curve fitting model was cubic model for both sexes(R2=0.805 for men and 0.722 for women).Conclusion Clavicle MRI can be used for the assessment of bone age in Chinese population.Complete epiphyseal plate closure can be used as a reliable indicator for the determination of age at 18 years old,and it is expected to achieve radiation-free forensic bone age assessment.

OBJECTIVE: To explore clinical efficacy of autologous platelet-rich plasma(PRP) in treating Rockwood type Ⅲ acromioclavicular dislocation. METHODS: From January 2019 to July 2021, 32 patients with Rockwood type Ⅲ acromioclavicular dislocation were treated with minimally invasive adjustable titanium plate internal fixation, and were divided into PRP group and control group according to whether PRP treatment was performed, with 16 patients in each group. In PRP group, there were 10 males and 6 females, aged from 28 to 47 years old with an average of (36.75±7.14) years old;the time from injury to surgery ranged from 1 to 31 h with an average of (26.13±3.98) h;5 patients on the left side and 11 patients on the right side;PRP was injected once during operation and the 4th and 8th weeks after operation respectively. In control group, there were 8 males and 8 females, aged from 30 to 52 years old with an average of (38.50±5.48) years old; the time from injury to surgery ranged from 1 to 29 h with an average of (25.48±3.11) h;7 patients on the left side and 9 patients on the right side; minimally invasive surgical treatment was performed. Visual analogue scale(VAS) was used to evaluate pain and Constant-Murley score for shoulder joint function was used to evaluate the recovery of shoulder joint movement function before operation and 1, 3, 6, and 12 months after operation respectively. RESULTS: All patients were followed up for 12 to 28 months with an average of (18.3±5.2) months. All incisions patients healed well without adverse events such as infection. Postoperative VAS of PRP group at 1, 3, and 6 months were (5.5±1.2), (3.7±1.6), and (2.4±1.2), respectively, while were lower than those of control group (6.6±1.4), (4.9±1.1), and (3.7±1.3), respectively;and had statistical differences between two groups (P<0.05). There was no statistically significant difference in VAS between two groups before operation and 12 months after operation (P>0.05). Postoperative Constant-Murley scores of PRP group at 1, 3, and 6 months were (64.09±11.61), (73.19±12.89), and (82.61±14.81) points, respectively, which were higher than those of control group were (52.32±17.42), (61.65±14.43), and (72.52±11.04) respectively;and the differences were statistically significant (P<0.05). There was no statistically significant difference in Constant-Murley scores at 12 months after operation between two groups (P>0.05). In PRP group, there was no statistically significant difference at 6 months and 12 months after operation (P>0.05), while there were statistically significant differences at the other time points (1 month after operation compared with before operation, 3 months after operation compared with 6 months after operation, and 3 months after operation compared with 1 month after operation) (P<0.05). In control group, there was no statistically significant difference when comparing 1 month and 3 months after operation (P>0.05), while at the other time points (1 month after operation with before operation, 3 months after operation with 6 months after operation, and 6 months after operation with 12 months after operation), the differences were all statistically significant (P<0.05). CONCLUSION Adjustable titanium plate fixation combined with postoperative injection of PRP for the treatment of Rockwood type III acromioclavicular joint dislocation has effect of promoting the recovery of shoulder joint function and reducing pain.
Humans ; Male ; Female ; Adult ; Middle Aged ; Platelet-Rich Plasma ; Acromioclavicular Joint/surgery* ; Bone Plates ; Titanium ; Joint Dislocations/therapy* ; Fracture Fixation, Internal/methods*