ObjectiveTo explore whether the mechanism of Shuangshen Ningxin capsules （SSNX） in alleviating myocardial ischemia-reperfusion injury （MIRI） in rats is related to the regulation of mitochondrial fission and fusion. MethodThis study focused on Sprague Dawley （SD） rats and ligated the left anterior descending branch of the coronary artery to construct a rat model of MIRI. The rats were divided into the sham operation group， model group， SSNX group （90 mg·kg^-1） and trimetazidine group （5.4 mg·kg^-1）. The activity of superoxide dismutase （SOD） and the content of malondialdehyde （MDA） were detected by micro method. Changes in mitochondrial membrane potential （△Ψm） and the degree of mitochondrial permeability transition pore （mPTP） opening were detected by the chemical fluorescence method. The intracellular adenosine triphosphate （ATP） level was detected by the luciferase assay. The messenger ribonucleic acid （mRNA） and protein expression levels of mitochondrial fission and fusion related factors dynamin-related protein 1 （DRP1）， mitochondrial fission 1 protein （FIS1）， optic atrophy protein 1 （OPA1）， mitochondrial outer membrane fusion protein 1 （MFN1）， and MFN2 were detected by real-time polymerase chain reaction （real-time PCR） and Western blot. ResultCompared with the sham operation group， the model group showed a decrease in serum SOD activity and an increase in MDA content. The opening level of mPTP， the level of △Ψm and ATP content decreased， the protein expressions of mitochondrial fission factors DRP1 and FIS1 increased， and the protein expressions and mRNA transcription levels of fusion related factors OPA1 and MFN1 decreased. Compared with the model group，SSNX significantly increased serum SOD activity， reduced MDA content， increased intracellular ATP level and △Ψm， reduced the opening level of mPTP， downregulated the protein expressions of mitochondrial fission factors DRP1 and FIS1， and increased the mRNA transcription levels and protein expressions of fusion related factors OPA1 and MFN1. ConclusionSSNX inhibits the expressions of mitochondrial fission factors DRP1 and FIS1， and increases the expressions of fusion related factors OPA1 and MFN1， inhibiting mitochondrial fission and increasing mitochondrial fusion， thereby alleviating MIRI.

This study aims to investigate the effect of salvianolic acid B (Sal B), the active ingredient of Salvia miltiorrhiza, on H9C2 cardiomyocytes injured by oxygen and glucose deprivation/reperfusion (OGD/R) through regulating mitochondrial fission and fusion. The process of myocardial ischemia-reperfusion injury was simulated by establishing OGD/R model. The cell proliferation and cytotoxicity detection kit (cell counting kit-8, CCK-8) was used to detect cell viability; the kit method was used to detect intracellular reactive oxygen species (ROS), total glutathione (t-GSH), nitric oxide (NO) content, protein expression levels of mitochondrial fission and fusion, apoptosis-related detection by Western blot. Mitochondrial permeability transition pore (MPTP) detection kit and Hoechst 33342 fluorescence was used to observe the opening level of MPTP, and molecular docking technology was used to determine the molecular target of Sal B. The results showed that relative to control group, OGD/R injury reduced cell viability, increased the content of ROS, decreased the content of t-GSH and NO. Furthermore, OGD/R injury increased the protein expression levels of dynamin-related protein 1 (Drp1), mitofusions 2 (Mfn2), Bcl-2 associated X protein (Bax) and cysteinyl aspartate specific proteinase 3 (caspase 3), and decreased the protein expression levels of Mfn1, increased MPTP opening level. Compared with the OGD/R group, it was observed that Sal B had a protective effect at concentrations ranging from 6.25 to 100 μmol·L^-1. Sal B decreased the content of ROS, increased the content of t-GSH and NO, and Western blot showed that Sal B decreased the protein expression levels of Drp1, Mfn2, Bax and caspase 3, increased the protein expression level of Mfn1, and decreased the opening level of MPTP. In summary, Sal B may inhibit the opening of MPTP, reduce cell apoptosis and reduce OGD/R damage in H9C2 cells by regulating the balance of oxidation and anti-oxidation, mitochondrial fission and fusion, thereby providing a scientific basis for the use of Sal B in the treatment of myocardial ischemia reperfusion injury.

Objective To investigate the environmental contamination related to first patient with carbapenem-re-sistant Acinetobacter baumannii(CRAB)infection and the infection status of relevant patients in a newly established intensive care unit(ICU)of a hospital in Tibetan area,and analyze the transmission risk.Methods From the ad-mission in ICU of a patients who was first detected CRAB on November 15,2021 to the 60th day of hospitalization,all patients who stayed in ICU for＞48 hours were performed active screening on CRAB.On the 30th day and 60th day of the admission to the ICU of the first CRAB-infected patient,environment specimens were taken respectively 2 hours after high-frequency diagnostic and therapeutic activities but before disinfection,and after disinfection but before medical activities.CRAB was cultured with chromogenic culture medium.Results Among the 13 patients who were actively screened,1 case was CRAB positive,he was transferred from the ICU of a tertiary hospital to the ICU of this hospital on November 19th.On the 40th day of admission to the ICU,he had fever,increased frequency for sputum suction,and CRAB was detected.The drug sensitivity spectrum was similar to that of the first case,and he also stayed in the adjacent bed of the first case.64 environmental specimens were taken,and 9 were positive for CRAB,with a positive rate of 14.06％,8 sampling points such as the washbasin,door handle and bed rail were positive for CRAB after high-frequency diagnostic and therapeutic activities.After routine disinfection,CRAB was detected from the sink of the washbasin.Conclusion For the prevention and control of CRAB in the basic-level ICU in ethnic areas,it is feasible to conduct risk assessment on admitted patients and adopt bundled prevention and con-trol measures for high-risk patients upon admission.Attention should be paid to the contaminated areas(such as washbasin,door handle,and bed rail)as well as the effectiveness of disinfection of sink of washbasin.

Objective To evaluate the predictive value of global longitudinal strain(GLS)measured by cardiac magnetic resonance(CMR)feature-tracking technique for left ventricular remodeling(LVR)after percutaneous coronary intervention(PCI)in patients with acute ST-segment elevation myocardial infarction(STEMI).Methods A total of 403 patients undergoing PCI for acute STEMI were prospectively recruited from multiple centers in China.CMR examinations were performed one week(7±2 days)and 6 months after myocardial infarction to obtain GLS,global radial strain(GRS),global circumferential strain(GCS),ejection fraction(LVEF)and infarct size(IS).The primary endpoint was LVR,defined as an increase of left ventricle end-diastolic volume by≥20%or an increase of left ventricle end-systolic volume by≥15%from the baseline determined by CMR at 6 months.Logistic regression analysis was performed to evaluate the predictive value of CMR parameters for LVR.Results LVR occurred in 101 of the patients at 6 months after myocardial infarction.Compared with those without LVR(n=302),the patients in LVR group exhibited significantly higher GLS and GCS(P<0.001)and lower GRS and LVEF(P<0.001).Logistic regression analysis indicated that both GLS(OR=1.387,95%CI:1.223-1.573;P<0.001)and LVEF(OR=0.951,95%CI:0.914-0.990;P=0.015)were independent predictors of LVR.ROC curve analysis showed that at the optimal cutoff value of-10.6%,GLS had a sensitivity of 74.3%and a specificity of 71.9%for predicting LVR.The AUC of GLS was similar to that of LVEF for predicting LVR(P=0.146),but was significantly greater than those of other parameters such as GCS,GRS and IS(P<0.05);the AUC of LVEF did not differ significantly from those of the other parameters(P>0.05).Conclusion In patients receiving PCI for STEMI,GLS measured by CMR is a significant predictor of LVR occurrence with better performance than GRS,GCS,IS and LVEF.

The approval mode of the traditional temporary procurement of medical consumables was introduced,and the common problems of temporary procurement of medical consumables were analyzed.Some countermeasures were put forward including reasonably formulating the management regulations of medical consumables,strictly following the principle of temporary procurement of medical consumables,optimizing the approval process,clearly defining the division of authority and responsibility of each department and perfecting the fine management system of medical consumables.References were provided for tertiary grade A hospitals to regulate the temporary procurement of medical consumables.[Chinese Medical Equipment Journal,2024,45(7):81-85]

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Objective To investigate the changing distribution and antibiotic resistance profiles of clinical isolates of Staphylococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Staphylococcus according to the unified protocol of CHINET(China Antimicrobial Surveillance Network)using disk diffusion method and commercial automated systems.The CHINET antimicrobial resistance surveillance data from 2015 to 2021 were interpreted according to the 2021 CLSI breakpoints and analyzed using WHONET 5.6.Results During the period from 2015 to 2021,a total of 204,771 nonduplicate strains of Staphylococcus were isolated,including 136,731(66.8％)strains of Staphylococcus aureus and 68,040(33.2％)strains of coagulase-negative Staphylococcus(CNS).The proportions of S.aureus isolates and CNS isolates did not show significant change.S.aureus strains were mainly isolated from respiratory specimens(38.9±5.1)％,wound,pus and secretions(33.6±4.2)％,and blood(11.9±1.5)％.The CNS strains were predominantly isolated from blood(73.6±4.2)％,cerebrospinal fluid(12.1±2.5)％,and pleural effusion and ascites(8.4±2.1)％.S.aureus strains were mainly isolated from the patients in ICU(17.0±7.3)％,outpatient and emergency(11.6±1.7)％,and department of surgery(11.2±0.9)％,whereas CNS strains were primarily isolated from the patients in ICU(32.2±9.7)％,outpatient and emergency(12.8±4.7)％,and department of internal medicine(11.2±1.9)％.The prevalence of methicillin-resistant strains was 32.9％in S.aureus(MRSA)and 74.1％in CNS(MRCNS).Over the 7-year period,the prevalence of MRSA decreased from 42.1％to 29.2％,and the prevalence of MRCNS decreased from 82.1％to 68.2％.MRSA showed higher resistance rates to all the antimicrobial agents tested except trimethoprim-sulfamethoxazole than methicillin-susceptible S.aureus(MSSA).Over the 7-year period,MRSA strains showed decreasing resistance rates to gentamicin,rifampicin,and levofloxacin,MRCNS showed decreasing resistance rates to gentamicin,erythromycin,rifampicin,and trimethoprim-sulfamethoxazole,but increasing resistance rate to levofloxacin.No vancomycin-resistant strains were detected.The prevalence of linezolid-resistant MRCNS increased from 0.2％to 2.3％over the 7-year period.Conclusions Staphylococcus remains the major pathogen among gram-positive bacteria.MRSA and MRCNS were still the principal antibiotic-resistant gram-positive bacteria.No S.aureus isolates were found resistant to vancomycin or linezolid,but linezolid-resistant strains have been detected in MRCNS isolates,which is an issue of concern.

Objective To evaluate the predictive value of global longitudinal strain(GLS)measured by cardiac magnetic resonance(CMR)feature-tracking technique for left ventricular remodeling(LVR)after percutaneous coronary intervention(PCI)in patients with acute ST-segment elevation myocardial infarction(STEMI).Methods A total of 403 patients undergoing PCI for acute STEMI were prospectively recruited from multiple centers in China.CMR examinations were performed one week(7±2 days)and 6 months after myocardial infarction to obtain GLS,global radial strain(GRS),global circumferential strain(GCS),ejection fraction(LVEF)and infarct size(IS).The primary endpoint was LVR,defined as an increase of left ventricle end-diastolic volume by≥20%or an increase of left ventricle end-systolic volume by≥15%from the baseline determined by CMR at 6 months.Logistic regression analysis was performed to evaluate the predictive value of CMR parameters for LVR.Results LVR occurred in 101 of the patients at 6 months after myocardial infarction.Compared with those without LVR(n=302),the patients in LVR group exhibited significantly higher GLS and GCS(P<0.001)and lower GRS and LVEF(P<0.001).Logistic regression analysis indicated that both GLS(OR=1.387,95%CI:1.223-1.573;P<0.001)and LVEF(OR=0.951,95%CI:0.914-0.990;P=0.015)were independent predictors of LVR.ROC curve analysis showed that at the optimal cutoff value of-10.6%,GLS had a sensitivity of 74.3%and a specificity of 71.9%for predicting LVR.The AUC of GLS was similar to that of LVEF for predicting LVR(P=0.146),but was significantly greater than those of other parameters such as GCS,GRS and IS(P<0.05);the AUC of LVEF did not differ significantly from those of the other parameters(P>0.05).Conclusion In patients receiving PCI for STEMI,GLS measured by CMR is a significant predictor of LVR occurrence with better performance than GRS,GCS,IS and LVEF.

Objective To investigate the occupational lead exposure and blood lead levels of workers in a lead-acid battery factory in Wuhan in 2020 and analyze the influencing factors of blood lead, and to provide reference for the blood lead intervention of the workers in the lead-acid battery factory. Methods The blood lead test results of 320 occupational lead-exposed workers in the factory were investigated and the influencing factors were analyzed. Results Among the 320 blood lead samples collected, 4 people had blood lead≥400 μg/L, accounting for 1.25%, and 89 people had blood lead≥200 μg/L, accounting for 27.81%. Among them, there were 235 males with a median blood lead of 155.10 μg/L, and 85 females with a median blood lead of 82.40 μg/L. The Wilcoxon rank sum test results of two independent samples showed that the overall blood lead level of male employees was higher than that of female employees, and the difference was statistically significant (P < 0.05). Blood samples were collected from employees of all ages, including 82 samples ≤40 years old , 160 samples 40-50 years old, and 78 samples >50 years old. Using the Bonferroni method to adjust the significance level for pairwise comparison, it was found that there were significant differences in the blood lead concentrations between the group under 40 years old, the group of 40 - 50 years old, and the group of over 50 years old ( P < 0.016 after adjustment). The employees were classified into different workshops, including 38 samples from the administrative workshop , 40 samples from the charging workshop, and 242 samples from the assembly workshop. Using the Bonferroni method to adjust the significance level for pairwise comparison, it was found that the blood lead concentrations in the administrative workshop, the charging workshop, and the assembly workshop were statistically different ( P <0.016 after adjustment). Conclusion The age, gender, and type of work of the employees in the battery factory all have a certain impact on the blood lead level. It is necessary to continuously improve the management of the labor hygiene operation system and strengthen the self-protection level of the workers, and regularly carry out occupational hygiene inspection and health monitoring.

ObjectiveTo explore the value of MRI ovarian-adnexal reporting and data system （O-RADS MRI） in differentiating benign and malignant ovarian-adnexal masses.MethodsTotally 146 patients （202 masses） with ovarian-adnexal lesions who underwent pelvic examination at 3.0 T MRI according to standardized scan protocol of O-RADS MRI and were pathologically confirmed in The First Affiliated Hospital of Sun Yat-sen University between January 2020 and February 2022 were retrospectively analyzed. Two radiologists classified the ovarian-adnexal masses as risk levels 1~5 according to O-RADS MRI and evaluated their consistency by Cohen’s kappa. Using pathological findings as the gold standard， the detection yield of malignant lesions with O-RADS MRI classification was analyzed. Sensitivity， specificity， accuracy， and the area under the receiver operating characteristic curve were calculated （cutoff for malignancy， score ≥ 4）.ResultsOf 202 masses， 62 （30.7%） were malignant， 140 （69.3%） were benign. The two radiologists presented good agreement in O-RADS MRI classification of ovarian adnexal masses （Kappa=0.932）. The malignancy rates of masses with scores of 1， 2， 3， 4 and 5 were 0%， 0%， 7.7%， 95%， 97.6%， respectively. Sensitivity， specificity， accuracy， and the area under the receiver operating characteristic curve were 96.8% （60/62）， 98.6% （138/140）， 98.0% （198/202）， 0.977.ConclusionsO-RADS MRI yields high diagnostic efficiency for benign and malignant ovarian adnexal masses and its widespread implementation will improve communication between radiologists and clinicians， and facilitate optimal patient management. Therefore， O-RADS MRI warrants widespread use in clinical setting.