ObjectiveTo establish a reliable chronic obstructive pulmonary disease (COPD) mouse model based on a self-developed multichannel automatic control system for long-term continuous cigarette smoke exposure in small animals using a novel continuous cigarette smoke exposure method, and to conduct phenotypic evaluation and analysis, thereby providing an animal experimental basis for investigating COPD pathogenesis and prevention strategies. MethodsTwenty male C57BL/6J mice aged 6 weeks were randomly and equally divided into a control group and a model group. The model group (n=10) underwent 6 h of continuous cigarette smoke exposure daily (6 cigarettes per day for 12 consecutive weeks), while the control group (n=10) received no intervention. Body weight was monitored biweekly. Post-exposure, in vivo micro-CT imaging was performed. After euthanasia, serum and bronchoalveolar lavage fluid (BALF) levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were quantified by ELISA. Lung tissues underwent H&E and Masson's trichrome staining to observe changes in lung morphology and inflammatory cell infiltration, and the mean linear intercept (MLI) was calculated, thereby comprehensively evaluating the clinical features of COPD in the mouse model. ResultsCompared with the control group, the model group showed significantly reduced body weight (P<0.01) from the fourth week. Compared with the control group, IL-6 level in the serum and BALF of the model group increased by 27.2% and 140.0%, respectively (P<0.01). TNF-α level in the serum and bronchoalveolar lavage fluid of the model group increased by 16.7% (P<0.01) and 19.3% (P<0.05), respectively. Histopathological examination revealed alveolar wall thinning, septal rupture, emphysematous bullae formation, reduced alveolar count, bronchial wall thickening with lumen narrowing, and inflammatory cell infiltration. MLI was significantly elevated (P<0.01). Masson's staining confirmed collagen deposition and bronchial remodeling. Micro-CT demonstrated localized high-density shadows exhibiting typical features of chronic bronchitis. Conclusion The self-developed device enables long-term continuous smoke exposure, and the successfully established COPD mouse model exhibits pathological features highly consistent with clinical manifestations, offering an efficient and reliable tool for COPD research.

AIM: To investigate the protective effect of β-sitosterol on retinal structure and function and its underlying molecular mechanism in a sodium iodate(NaIO3)-induced mouse model of dry age-related macular degeneration(ARMD).METHODS: A dry ARMD mouse model was established by NaIO3 injection. The therapeutic effect of β-sitosterol intervention was evaluated using fundus photography, histopathology(HE staining), and electroretinography(ERG). Network pharmacology was employed to screen potential targets of β-sitosterol in ARMD, and molecular docking was used to validate the binding ability between β-sitosterol and these targets. The impact of β-sitosterol on ARPE-19 cell viability and apoptosis pathways was analyzed using CCK-8 assay, Hoechst staining, and Western blotting.RESULTS: The β-sitosterol significantly alleviated structural damage in the retinas of model mice(increased retinal and outer nuclear layer thickness, reduced yellowish-white drusen-like deposits)and functional impairment(partial restoration of a-wave and b-wave amplitudes). Network pharmacology identified PON1 as a key target of β-sitosterol; molecular docking demonstrated that β-sitosterol binds to PON1 via hydrophobic interactions and hydrogen bonds. In vitro experiments showed that β-sitosterol(10 μmol/L)significantly increased ARPE-19 cell viability(P<0.01), reduced apoptosis(P<0.01), upregulated PON1 expression(P<0.01), and concurrently suppressed cleaved-Caspase3 expression(P<0.01).CONCLUSION: The β-sitosterol likely protects against oxidative stress-induced retinal damage by modulating PON1 to suppress the Caspase3-dependent apoptotic pathway. These findings provide experimental evidence supporting the development of β-sitosterol as a novel therapeutic agent for dry ARMD.

Central positional nystagmus （CPN） is a form of positional nystagmus caused by lesions of the central vestibular system. Since the clinical manifestations and nystagmus features of CPN are highly similar with those of benign paroxysmal positional vertigo， the diagnosis of CPN is highly challenging. The etiology of CPN is complex， involving both structural lesions such as stroke and tumors and non-structural disorders such as vestibular migraine. The primary lesion sites of CPN included the cerebellar nodulus， the uvula， and the tonsil. CPN can be classified into paroxysmal （transient） CPN and persistent CPN. The clinical features of paroxysmal CPN （including latency， duration， direction， intensity， and their correlation with the type and speed of positional maneuvers） suggest that it originates from the semicircular canal， and its pathogenesis involves post-rotatory rebound nystagmus caused by the disinhibition of irregular afferent signals transmitted to the vestibular nuclei due to central damage （often involving the cerebellar nodulus and the uvula）. Persistent CPN may be caused by damage to the velocity storage pathway， resulting in an erroneous assessment of gravity direction and inertia. This article summarizes the latest advances in the etiology， lesion sites， pathogenesis， clinical features， differential diagnosis， and treatment of CPN in China and globally， in order to help clinicians better understand and identify CPN and thus achieve timely diagnosis and effective treatment.
Uvula

Objective:To investigate renal impairment and ferroptosis due to severe blast injuries and related mechanism.Methods:The goats were placed 3 meters away from the center of an 8 kg TNT-equivalent explosive to carry out blast injury experiments.The physical parameters of blast waves were measured,and the pathological severity of blast injuries was graded and scored to assess the severity of injuries.Vital signs,blood gas parameters,and renal function markers were measured before injury and at 1,3,6,and 24 hours after injury.Renal tissue samples were collected at 24 hours after injury to prepare tissue sections,which were used to perform HE staining and measure the changes in the content of Fe2+and the expression of the ferroptosis-related marker proteins xCT and GPX4 in renal tissue,and Prussian blue staining was performed for renal tissue sections to investigate the mechanism associated with renal impairment and ferroptosis of renal cells.Results:Severe blast injuries accounted for the highest proportion of 47.2%in experi-mental goats,while mild,moderate,severe,and extremely severe injuries accounted for 2.8%,36.1%,47.2%,and 13.9%,respectively,and the pathologic severity score of blast injury was 2.56±0.15.For the goats after blast injury,there were significant increases in heart rate(F=12.750,P<0.01)and respiratory rate(F=6.500,P<0.01)and significant reductions in anal temperature(F=3.496,P<0.05),partial pressure of blood oxygen(F=24.630,P<0.01),and blood oxygen saturation(F=18.560,P<0.01),as well as significant increases in the levels of blood uric acid(F=22.320,P<0.01),serum creatinine(F=15.350,P<0.01),and blood urea nitrogen(F=22.310,P<0.01).Compared with the control group,swelling of renal tubular epithelial cells and narrowing of tubular lumen were observed at 24 hours after blast injury,with a significant increase in the content of Fe2+in renal tissue(t=5.933,P<0.01),significant reductions in the relative expression protein levels of GPX4(t=7.924,P<0.01)and xCT(t=4.483,P<0.01)in renal tissue,and deposi-tion of a large amount of iron ions in renal tubular epithelial cells.Conclusion:Experimental goats placed 3 meters away from the cen-ter of an 8 kg TNT-equivalent explosive can cause severe blast inju-ries,resulting in the onset of hypoxia,renal impairment,and ferrop-tosis of renal tubular epithelial cells.

OBJECTIVES: To investigate the regulatory effects of Aurora-A in regulating proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of cervical cancer cells and the role of actin-related protein 2/3 complex subunit 4 (ARPC4) in mediating its effects. METHODS: The plasmids pCDH-NC, pCDH-Aurora-A, and shRNA-ARPC4 were used for inducing Aurora-A overexpression or ARPC4 knockdown in HeLa cells. The cells were divided into vector group, Aurora-A overexpression group, Aurora-A overexpression+ARPC4 knockdown group, and Aurora-A overexpression+NF‑κBp65 inhibitor group and transfected with the corresponding plasmids. The proliferation, colony-forming ability, migration and invasion of the treated Hela cells was evaluated using EdU immunofluorescence assay, crystal violet staining, scratch assay, Transwell assay, and Matrigel assay. Western blotting was performed to detect the changes in cellular expressions of EMT-related proteins and expression levels of NF-κBp65 and ARPC4. RESULTS: The expression of ARPC4 was significantly decreased in HeLa cells with Aurora-A knockdown and increased in Aurora-A-overexpressing cells. Aurora-A overexpression obviously promoted proliferation, migration, and invasion abilities of HeLa cells, and these effects was significantly antagonized by ARPC4 knockdown. In Aurora-A-overexpressing cells, the phosphorylation level of NF-κBp65 and the expression level of ARPC4 were increased significantly, and application of the NF‑κBp65 inhibitor obviously lowered the expression level of ARPC4. CONCLUSIONS Aurora-A overexpression upregulates the expression of ARPC4 by activating the NF-κBp65 signaling pathway, thereby promoting migration, invasion and EMT of HeLa cells.
Humans ; Uterine Cervical Neoplasms/metabolism* ; Female ; HeLa Cells ; Epithelial-Mesenchymal Transition ; Signal Transduction ; Cell Movement ; Neoplasm Invasiveness ; Cell Proliferation ; Aurora Kinase A/metabolism* ; Transcription Factor RelA/metabolism* ; Neoplasm Metastasis

Objective To understand the changing composition and antibiotic resistance of bacterial species in the clinical isolates from outpatient and emergency department(hereinafter referred to as outpatients)and inpatient children over time in various hospitals,and to provide laboratory evidence for rational antibiotic use.Methods The data on clinically isolated pathogenic bacteria and antimicrobial susceptibility of isolates from outpatients and inpatient children in the CHINET program from 2015 to 2021 were collected and analyzed.Results A total of 278 471 isolates were isolated from pediatric patients in the CHINET program from 2015 to 2021.About 17.1％of the strains were isolated from outpatients,primarily group A β-hemolytic Streptococcus,Escherichia coli,and Staphylococcus aureus.Most of the strains(82.9％)were isolated from inpatients,mainly SS.aureus,E.coli,and H.influenzae.The prevalence of methicillin-resistant S.aureus(MRSA)in outpatients(24.5％)was lower than that in inpatient children(31.5％).The MRSA isolates from outpatients showed lower resistance rates to the antibiotics tested than the strains isolated from inpatient children.The prevalence of vancomycin-resistant Enterococcus faecalis or E.faecium and penicillin-resistant S.pneumoniae was low in either outpatients or inpatient children.S.pneumoniae,β-hemolytic Streptococcus and S.viridans showed high resistance rates to erythromycin.The prevalence of erythromycin-resistant group A β-hemolytic Streptococcus was higher in outpatients than that in inpatient children.The prevalence of β-lactamase-producing H.influenzae showed an overall upward trend in children,but lower in outpatients(45.1％)than in inpatient children(59.4％).The prevalence of carbapenem-resistant Klebsiella pneumoniae(CRKpn),carbapenem-resistant Pseudomonas aeruginosa(CRPae)and carbapenem-resistant Acinetobacter baumannii(CRAba)was 14％,11.7％,47.8％in outpatients,but 24.2％,20.6％,and 52.8％in inpatient children,respectively.The prevalence of multidrug-resistant E.coli,K.pneumoniae,Proteus mirabilis,P.aeruginosa and A.baumannii strains was lower in outpatients than in inpatient children.The prevalence of fluoroquinolone-resistant E.coli,ESBLs-producing K.pneumoniae,ESBLs-producing P.mirabilis,carbapenem-resistant E.coli(CREco),CRKpn,and CRPae was lower in children in outpatients than in inpatient children,but the prevalence of CRAba in 2021 was higher than in inpatient children.Conclusions The distribution of clinical isolates from children is different between outpatients and inpatients.The prevalence of MRSA,ESBL,and CRO was higher in inpatient children than in outpatients.Antibiotics should be used rationally in clinical practice based on etiological diagnosis and antimicrobial susceptibility test results.Ongoing antimicrobial resistance surveillance and prevention and control of hospital infections are crucial to curbing bacterial resistance.

Objective To investigate the changing antibiotic resistance profiles of E.coli isolated from patients in the 52 hospitals participating in the CHINET program from 2015 to 2021.Methods Antimicrobial susceptibility was tested for clinical isolates of E.coli according to the unified protocol of CHINET program.WHONET 5.6 and SPSS 20.0 software were used for data analysis.Results Atotal of 289 760 nonduplicate clinical strains ofE.coli were isolated from 2015 to 2021,mainly from urine samples(44.7±3.2)％.The proportion of E.coli strains isolated from urine samples was higher in females than in males(59.0％vs 29.5％).The proportion of E.coli strains isolated from respiratory tract and cerebrospinal fluid samples was significantly higher in children than in adults(16.7％vs 7.8％,0.8％vs 0.1％,both P＜0.05).The isolates from internal medicine department accounted for the largest proportion(28.9±2.8)％with an increasing trend over years.Overall,the prevalence of ESBLs-producing E.coli and carbapenem resistant E.coli(CREco)was 55.9％and 1.8％,respectively during the 7-year period.The prevalence of ESBLs-producing E.coli was the highest in tertiary hospitals each year from 2015 to 2021 compared to secondary hospitals.The prevalence of CREco was higher in children's hospitals compared to secondary and tertiary hospitals each year from 2015 to 2021.The prevalence of ESBLs-producing E.coli in tertiary hospitals and children's hospitals and the prevalence of CREco in children's hospitals showed a decreasing trend over the 7-year period.The prevalence of CREco in secondary and tertiary hospitals increased slowly.Antibiotic resistance rates changed slowly from 2015 to 2021.Carbapenem drugs(imipenem,meropenem)were the most active drugs amongβ-lactams against E.coli(resistance rate≤2.1％).The resistance rates of E.coli to β-lactam/β-lactam inhibitor combinations(piperacillin-tazobactam,cefoperazone-sulbactam),aminoglycosides(amikacin),nitrofurantoin and fosfomycin(for urinary isolates only)were all less than 10％.The resistance rate of E.coli strains to antibiotics varied with the level of hospitals and the departments where the strains were isolated,especially for cefazolin and ciprofloxacin,to which the resistance rate of E.coli strains from children in non-ICU departments was significantly lower than that of the strains isolated from other departments(P＜0.05).The E.coli isolates from ICU showed higher resistance rate to most antimicrobial agents tested(excluding tigecycline)than the strains isolated from other departments.The E.coli strains isolated from tertiary hospitals showed higher resistance rates to the antimicrobial agents tested(excluding tigecycline,polymyxin B,cefepime and carbapenems)than the strains from secondary hospitals and children's hospitals.Conclusions E.coli is an important pathogen causing clinical infection.More than half of the clinical isolates produced ESBL.The prevalence of CREco is increasing in secondary and tertiary hospitals over the 7-year period even though the overall prevalence is still low.This is an issue of concern.

Objective:To describe the clinical and pathological features of patients with myofasciitis.Methods:The clinical manifestations and auxiliary examination (laboratory, electromyogram, imaging and muscle biopsy) results of 52 patients with myofasciitis diagnosed by pathology at Peking University First Hospital from August 2002 to December 2024 were collected and analyzed.Results:Among the 52 patients (33 males and 19 females), the age of disease onset was (34.4±16.4) years (6.0-73.0 years) and the disease duration was 17.7 (0.3, 120.0) months; the main symptoms included myalgia in the distal limbs (28 cases, 53.8%), diffuse cutaneous or muscle sclerosis (21 cases, 40.4%), muscle weakness (22 cases, 42.3%) and limited joint activity (23 cases, 44.2%); 12 patients (23.1%) were combined with other diseases. All patients had no history of vaccination. Laboratory examinations showed that 80.8% (21/26) of patients had elevated C-reactive protein, 80.0% (20/25) had elevated erythrocyte sedimentation rate, and 26.5% (9/34) had elevated creatine kinase. Among 19 patients undergoing electromyography, 6 cases showed myogenic changes, 4 cases showed neurogenic changes, 1 case showed both myogenic and neurogenic changes, and 8 cases showed no obvious abnormality. Myofascial edema was observed in all 15 patients who underwent muscle magnetic resonance imaging, with partial involvement of adjacent muscles in some cases. According to myopathological changes, the 52 patients were divided into macrophagic myofasciitis in 41 cases (78.8%), lymphocytic myofasciitis in 7 cases (13.5%), and eosinophilic fasciitis in 4 cases (7.7%). Among the 52 patients, fibroblast proliferation in the myofascia was present in 39 cases (75.0%), subfascial muscle fiber atrophy in 28 cases (53.8%), and scattered muscle fiber necrosis and regeneration in 15 cases (28.8%). Major histocompatibility complex class Ⅰexpression on muscle fibers was positive in 89.5% (34/38) of patients, and membrane attack complex deposition on muscle fibers and/or capillary walls was present in 39.5% (15/38) of patients. Among 25 patients with follow-up, all received low-dose oral glucocorticoids, and 7 additionally received methotrexate, intravenous immunoglobulin, or hydroxychloroquine. During follow-up, 22 patients showed clinical improvement, 1 patient remained stable, and 2 patients died.Conclusions:Non-vaccine-associated macrophagic myofasciitis is the most common pathological subtype of myofasciitis. A few patients are concomitant with other diseases. Muscle magnetic resonance imaging is helpful in the diagnosis of the disease. Most patients respond to immunosuppressive treatment.

Objective:To report the clinical, imaging, and pathological features of a case of MYH7 gene-related scapuloperoneal myosin storage myopathy. Methods:Clinical data were collected from a patient with MYH7 gene-related scapuloperoneal myosin storage myopathy who presented to Peking University First Hospital in February 2025. The patient was evaluated with muscle magnetic resonance imaging, muscle biopsy, and whole-exome sequencing. Results:The patient was a 52-year-old female, with a 12-year history of progressive difficulty in foot dorsiflexion, exercise-induced fatigue, and lower limb pain. Over the past 3 years, she developed proximal upper limb weakness and post-exertional myalgia. Physical examination revealed scapuloperoneal weakness distribution accompanied by sensorineural hearing loss. Electromyography demonstrated myogenic changes in the deltoid and tibialis anterior muscles. Serum creatine kinase levels were within normal limits. Lower limb magnetic resonance imaging showed mild atrophy of the thigh muscles and significant fatty infiltration in the tibialis anterior, extensor hallucis longus, and extensor digitorum longus. Tibialis anterior muscle biopsy revealed dystrophic-like changes with sub-sarcolemmal hyaline bodies containing abundant granulofilamentous material. Whole exome sequencing identified a heterozygous pathogenic variant of c.5352_5354del(p.K1784del) in the MYH7 gene. Conclusions:This patient is the first reported one in China with MYH7 gene-related scapuloperoneal myosin storage myopathy, exhibiting characteristic scapuloperoneal weakness, selective fatty infiltration of the anterior lower leg muscles on imaging and sub-sarcolemmal hyaline body pathological changes. The diagnosis of this disease relies on characteristic pathological findings and genetic test results.