ObjectiveTo elucidate the effects of autonomic neuromodulators [calcium chloride (CaCl₂)-acetylcholine (ACh)] on atrial electrical remodeling and histopathological changes in rats, thereby providing evidence for further investigation into the pathological mechanisms by which autonomic imbalance induces atrial fibrillation (AF). MethodsTen 8-week-old male Sprague-Dawley (SD) rats were randomly divided into experimental and control groups, with 5 rats in each group. The experimental group received daily tail vein injections of a CaCl₂-ACh mixed solution for 28 days, while the control group received an equal volume of saline. Surface electrocardiograms were recorded before and after daily administration. On day 28 of administration, under isoflurane inhalation anesthesia, echocardiography was performed, and then the rats were euthanized by exsanguination under isoflurane anesthesia for tissue collection. Body weight and heart weight of rats were measured, and electrophysiological parameters including AF inducibility, conduction velocity, and conduction dispersion in isolated rat hearts were monitored using the MappingLab multichannel electrophysiological mapping system. HE staining was performed to evaluate atrial tissue architecture and inflammatory cell infiltration. The expression levels of matrix metalloproteinase 9 (MMP-9) and interleukin-1 beta (IL-1β) were analyzed by Western blotting. Masson staining was used to quantitatively analyze the proportional distribution of collagen fibers and myocardial fibers, and to calculate the area of collagen deposition, thereby evaluating the degree of myocardial fibrosis. Wheat germ agglutinin (WGA) staining was used to evaluate morphological changes of cardiomyocytes. Dihydroethidium (DHE) staining was used to detect the level of oxidative stress in atrial myocytes. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining was used to detect atrial cell apoptosis. ResultsCompared with the control group, the experimental group showed obvious arrhythmias on electrocardiograms. Echocardiography after 28 days of administration revealed significant structural remodeling in the experimental group, with a marked increase in left atrial anteroposterior diameter (P < 0.05), and also showed cardiac dysfunction, with significant decreases in left ventricular ejection fraction and left ventricular fractional shortening (P < 0.01). Compared with the control group, the experimental group showed a significantly increased heart weight-to-body weight ratio (P < 0.05), a markedly higher AF inducibility (P < 0.001), a significantly slowed atrial conduction velocity (P < 0.05), an uneven isochronal map with irregular directions, and a significantly increased conduction dispersion (P < 0.01). HE staining showed that atrial myocytes in the experimental group were disorganized, with slight inflammatory cell infiltration. Western blotting showed that the expression levels of MMP-9 and IL-1β in the atrial tissue of the experimental group were significantly upregulated (P < 0.05). Masson staining showed a significant increase in collagen deposition and a significant increase in fibrosis area in the atrial tissue of the experimental group (P < 0.001). WGA staining showed that cardiomyocytes in the experimental group were significantly hypertrophied compared with the control group (P < 0.05). DHE staining and TUNEL staining revealed that the level of oxidative stress in atrial myocytes (P < 0.001) and the apoptotic rate (P < 0.01) were both significantly increased. Conclusion Daily tail vein injections of the autonomic neuromodulator CaCl₂-ACh mixed solution for 28 days can successfully induce AF in rats, accompanied by significant atrial structural remodeling, electrical remodeling, and oxidative stress.

ObjectiveTo elucidate the mechanism by which total flavonoids of Abelmoschi Corolla （TFA） treat immunoglobulin A （IgA） nephropathy （IgAN） through serum metabolomics analysis. MethodsSPF-grade male SD rats were randomly assigned into six groups （n=10）： blank， model， low-dose TFA （TFA-L， 27 mg·kg^-1）， medium-dose TFA （TFA-M， 54 mg·kg^-1）， high-dose TFA （TFA-H， 108 mg·kg^-1）， and losartan potassium （LST， 4.5 mg·kg^-1） groups. The remaining five groups， excluding the blank group， were modeled with bovine serum albumin （BSA）， lipopolysaccharide （LPS）， and carbon tetrachloride （CCl₄）. Specifically， from weeks 1 to 10， BSA was administered via gavage every other day， and a mixture of castor oil and CCl₄ was injected subcutaneously once a week， with LPS injected into the tail vein at weeks 6 and 8. After successful modeling， each intervention group was administrated with the medication prepared with distilled water once daily by gavage for a continuous period of 4 weeks. The levels of 24-hour urinary total protein （24 h UP） and serum creatinine （SCr） were quantified by kits， and the serum IgA level was determined by enzyme-linked immunosorbent assay （ELISA）. Renal pathological changes were observed by hematoxylin-eosin （HE） staining and periodic acid-Schiff （PAS） staining. Renal IgA deposition was assessed by immunofluorescence （IF）. Endoplasmic reticulum （ER） stress was observed by transmission electron microscopy. Western blot and immunohistochemistry （IHC） were employed to detect the expression of ER stress-related factors. Non-targeted metabolomics was used to screen differential metabolites for analysis， and key metabolites arachidonic acid （AA）， prostaglandin E₂ （PGE₂）， and cyclooxygenase-2 （COX-2） were validated. ResultsCompared with the blank group， the model group showed increased 24-hour urine protein （24 h UP） and serum creatinine （SCr） levels （P<0.01）， obvious renal pathological damage， elevated serum IgA level （P<0.01）， increased renal AA and PGE₂ levels （P<0.01）， and up-regulated protein levels of COX-2， glucose-regulated protein 78 （GRP78）， phosphorylated eukaryotic initiation factor 2α （P-EIF2α）， activating transcription factor 4 （ATF4）， inositol-requiring enzyme 1α （IRE1α）， and spliced X-box binding protein 1 （XBP1s） in the renal tissue （P<0.05， P<0.01）. Compared with the model group， the intervention groups showed reductions in 24 h UP and SCr levels （P<0.05， P<0.01）， alleviated renal pathological injury， decreased serum IgA level （P<0.05， P<0.01）， and reduced renal AA and PGE₂ levels （P<0.01）. Western blot and IHC results showed that TFA reduced the levels of COX-2， GRP78， P-EIF2α， ATF4， IRE1α， and XBP1s in the renal tissue （P<0.05， P<0.01）. Metabolomics results indicated that 51 commonly differential metabolites were found among the normal， model， and TFA-M groups. TFA ameliorated IgAN by affecting metabolic pathways related to the biosynthesis of arachidonic acid and arginine through L-aspartic acid， prostaglandin 2α， leukotriene B₄， leukotriene D₄， among others. ConclusionTFA can regulate the arachidonic acid metabolism pathway， thereby modulating ER stress， reducing renal damage， and ameliorating IgA nephropathy.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

OBJECTIVE To analyze the status of targeted monitoring of the health care-associated infections in in-tensive care unit(ICU)of a three-A hospital of northwest China in recent 7 years so as to provide bases for formu-lating effective prevention and control measures for the health care-associated infections.METHODS The related data were successively collected from the ICU hospitalized patients of the Second Affiliated Hospital of Air Force Medical University who were under the targeted monitoring by nosocomial infection real-time monitoring system from Jan.2017 to Dec.2023.The data included the incidence of infections,infection sites,use of catheters,inci-dence of catheter-related infections,and distribution and prevalence trend of pathogens.RESULTS A total of 49,137 hospitalized patients from five ICU wards of respiratory medicine department,neurosurgery department,neurology department,thoracic surgery department and critical care medicine department were under the monito-ring,1446(1681 case-times)of whom had health care-associated infections,with the infection rate 2.94％,the case-time infection rate 3.42％.The respiratory system was the major infection site of the patients with the health care-associated infections.Among the patients with instrument-associated infections,20.70％had ventilator-asso-ciated pneumonia(VAP),5.71％had urinary catheter-associated urinary tract infection(CAUTI),and 1.96％had catheter-related bloodstream infection(CRBSI).Totally 405 strains of non-repetitive pathogens were isolated from 477 patients with instruments-associated infections,78.77％of which were gram-negative bacteria.The iso-lation rate of multidrug-resistant organisms(MDROs)was 44.12％,and Acinetobacter baumannii was the pre-dominant species of pathogen isolated from the patients with VAP.CONCLUSIONS The targeted monitoring of health care-associated infections may facilitate the awareness of dynamic changes of the infections in a accurate and timely manner so as to provide bases for developing effective prevention and control measures for the health care-associated infection.It is necessary to strengthen the prevention and control of the infections in critical care medi-cine department,neurosurgery department as well as the lower respiratory tract infections and prevent the MDROs infection in the meantime.

Objective:To evaluate the efficacy and safety of upadacitinib in the real-world treatment of difficult-to-treat Crohn's disease (DTT-CD) .Methods:This multicenter, retrospective cohort study included patients diagnosed with DTT-CD according to the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) criteria, and treated at eight Chinese inflammatory bowel disease centers between January 2023 and March 2025. Clinical outcomes were assessed after 12 weeks of induction therapy with upadacitinib (45 mg qd), including clinical remission rate, clinical response rate, and incidence of adverse events.Results:Among 151 enrolled DTT-CD patients, the clinical remission rate was 47.0%, and the clinical response rate was 90.7% after 12 weeks of treatment. Adverse events occurred in 42 cases (27.8%) .Conclusion:Upadacitinib demonstrated favorable efficacy in inducing clinical remission in DTT-CD patients, with a good safety profile at the induction dose (45 mg qd) .

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective:To evaluate the efficacy and safety of upadacitinib in the real-world treatment of difficult-to-treat Crohn's disease (DTT-CD) .Methods:This multicenter, retrospective cohort study included patients diagnosed with DTT-CD according to the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) criteria, and treated at eight Chinese inflammatory bowel disease centers between January 2023 and March 2025. Clinical outcomes were assessed after 12 weeks of induction therapy with upadacitinib (45 mg qd), including clinical remission rate, clinical response rate, and incidence of adverse events.Results:Among 151 enrolled DTT-CD patients, the clinical remission rate was 47.0%, and the clinical response rate was 90.7% after 12 weeks of treatment. Adverse events occurred in 42 cases (27.8%) .Conclusion:Upadacitinib demonstrated favorable efficacy in inducing clinical remission in DTT-CD patients, with a good safety profile at the induction dose (45 mg qd) .

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

OBJECTIVE To analyze the status of targeted monitoring of the health care-associated infections in in-tensive care unit(ICU)of a three-A hospital of northwest China in recent 7 years so as to provide bases for formu-lating effective prevention and control measures for the health care-associated infections.METHODS The related data were successively collected from the ICU hospitalized patients of the Second Affiliated Hospital of Air Force Medical University who were under the targeted monitoring by nosocomial infection real-time monitoring system from Jan.2017 to Dec.2023.The data included the incidence of infections,infection sites,use of catheters,inci-dence of catheter-related infections,and distribution and prevalence trend of pathogens.RESULTS A total of 49,137 hospitalized patients from five ICU wards of respiratory medicine department,neurosurgery department,neurology department,thoracic surgery department and critical care medicine department were under the monito-ring,1446(1681 case-times)of whom had health care-associated infections,with the infection rate 2.94％,the case-time infection rate 3.42％.The respiratory system was the major infection site of the patients with the health care-associated infections.Among the patients with instrument-associated infections,20.70％had ventilator-asso-ciated pneumonia(VAP),5.71％had urinary catheter-associated urinary tract infection(CAUTI),and 1.96％had catheter-related bloodstream infection(CRBSI).Totally 405 strains of non-repetitive pathogens were isolated from 477 patients with instruments-associated infections,78.77％of which were gram-negative bacteria.The iso-lation rate of multidrug-resistant organisms(MDROs)was 44.12％,and Acinetobacter baumannii was the pre-dominant species of pathogen isolated from the patients with VAP.CONCLUSIONS The targeted monitoring of health care-associated infections may facilitate the awareness of dynamic changes of the infections in a accurate and timely manner so as to provide bases for developing effective prevention and control measures for the health care-associated infection.It is necessary to strengthen the prevention and control of the infections in critical care medi-cine department,neurosurgery department as well as the lower respiratory tract infections and prevent the MDROs infection in the meantime.