OBJECTIVE To investigate the current status of contamination with carbapenem-resistant gram-negative bacteria in environment of intensive care units(ICU)of tertiary hospitals in Shanghai and find out the potential contamination sources so as to provide bases for prevention and control of multidrug-resistant organisms infec-tions in the ICUs.METHODS The surroundings of the ICU patients detected with CRGNB and environmental ob-jects surfaces in public area were sampled by mSuperCARBA chromogenic media from Dec.2024 to Jan.2025,the strains were isolated,and the targeted strains were identified by matrix-assisted laser desorption/ionization time-of-flight(MALDI-TOF)mass spectrometer.RESULTS A total of 653 samples were collected in the survey,76 of which were positive for bacterial culture,60 were detected with CRGNB,and the isolation rate of CRGNB was 9.19％.The isolation rate of CRGNB was 53.40％in the water-source group,0.91％in the non-water-source group,and there was significant difference(x2=286.450,P＜0.001).The result of whole genome sequencing for 17 strains of CRKP showed that ST11 and ST15 were the two major types of multilocus typing(MT),respective-ly carrying 2-12 types of drug resistance genes.CONCLUSIONS The CRGNB strains are detected in some environ-mental sites of the ICUs of 15 tertiary hospitals in Shanghai,and the isolation rate of CRKP is highest among them.The colonization rate of CRGNB is relatively low on the highly frequent-contact object surfaces of the ICUs,however,sink drain holes poses a risk of hospital-acquired CRGNB infections transmissions.Additionally,the ba-sins and towels of the CRGNB patients are hard to be thoroughly cleaned,disinfected and dried,resulting in a high contamination rate.

Objective·To develop a nomogram prediction model and an online risk calculator,and to predict the continence of patients after robot-assisted laparoscopic radical prostatectomy(RARP).Methods·A total of 604 prostate cancer patients who underwent RARP and had preoperative prostate magnetic resonance imaging at the Shanghai General Hospital,Shanghai Jiao Tong University School of Medicine from September 2022 to December 2024 were analyzed and included.All patients were randomly resampled and divided into a training set(n=420)and a validation set(n=184)at a ratio of 7∶3.The patients'continence was followed up every month from the first month after the operation.The least absolute shrinkage and selection operator(LASSO)model was applied to screen the features.A Logistic multivariate regression analysis was used to establish a prediction model integrating the features selected from the LASSO analysis.The receiver operator characteristic(ROC)curve was drawn to predict the recovery of continence in patients after RARP,and the areas under the curve were compared by the DeLong test to evaluate the discrimination of the model.Calibration curves and decision curve analysis(DCA)were used to evaluate the calibration and clinical utility the model.Results·According to the postoperative continence follow-up data of the patients,the continence rate of the patients at 3 months after the operation was 58.28%(352/604).The length of the membranous urethra,the thickness of the right levator ani muscle,and blood loss were identified as independent predictors of early postoperative(3-month)incontinence by Logistic multivariate regression analysis of the training set.The area under the ROC curve was calculated as 0.976(0.954,0.998)for the training set and 0.977(0.945,1.000)for the validation set,demonstrating good discrimination of this model.No significant difference between the ROC curves of the training set and the validation set was confirmed by the DeLong test(P=0.949).A good goodness of fit of this model was demonstrated by the Hosmer-Lemeshow test(P=0.179).The clinical utility of the nomogram prediction model was indicated by the DCA plot.This nomogram prediction model was incorporated into an online calculator(https://yitingd.shinyapps.io/DynNomapp).Conclusion·This study developed and validated a nomogram prediction model that can effectively predict the early continence of patients after RARP.The length of the membranous urethra,the thickness of the right levator ani muscle,and the intraoperative blood loss are significant independent predictors of early postoperative incontinence.

Objective·To develop a nomogram prediction model and an online risk calculator,and to predict the continence of patients after robot-assisted laparoscopic radical prostatectomy(RARP).Methods·A total of 604 prostate cancer patients who underwent RARP and had preoperative prostate magnetic resonance imaging at the Shanghai General Hospital,Shanghai Jiao Tong University School of Medicine from September 2022 to December 2024 were analyzed and included.All patients were randomly resampled and divided into a training set(n=420)and a validation set(n=184)at a ratio of 7∶3.The patients'continence was followed up every month from the first month after the operation.The least absolute shrinkage and selection operator(LASSO)model was applied to screen the features.A Logistic multivariate regression analysis was used to establish a prediction model integrating the features selected from the LASSO analysis.The receiver operator characteristic(ROC)curve was drawn to predict the recovery of continence in patients after RARP,and the areas under the curve were compared by the DeLong test to evaluate the discrimination of the model.Calibration curves and decision curve analysis(DCA)were used to evaluate the calibration and clinical utility the model.Results·According to the postoperative continence follow-up data of the patients,the continence rate of the patients at 3 months after the operation was 58.28%(352/604).The length of the membranous urethra,the thickness of the right levator ani muscle,and blood loss were identified as independent predictors of early postoperative(3-month)incontinence by Logistic multivariate regression analysis of the training set.The area under the ROC curve was calculated as 0.976(0.954,0.998)for the training set and 0.977(0.945,1.000)for the validation set,demonstrating good discrimination of this model.No significant difference between the ROC curves of the training set and the validation set was confirmed by the DeLong test(P=0.949).A good goodness of fit of this model was demonstrated by the Hosmer-Lemeshow test(P=0.179).The clinical utility of the nomogram prediction model was indicated by the DCA plot.This nomogram prediction model was incorporated into an online calculator(https://yitingd.shinyapps.io/DynNomapp).Conclusion·This study developed and validated a nomogram prediction model that can effectively predict the early continence of patients after RARP.The length of the membranous urethra,the thickness of the right levator ani muscle,and the intraoperative blood loss are significant independent predictors of early postoperative incontinence.

OBJECTIVE To investigate the current status of contamination with carbapenem-resistant gram-negative bacteria in environment of intensive care units(ICU)of tertiary hospitals in Shanghai and find out the potential contamination sources so as to provide bases for prevention and control of multidrug-resistant organisms infec-tions in the ICUs.METHODS The surroundings of the ICU patients detected with CRGNB and environmental ob-jects surfaces in public area were sampled by mSuperCARBA chromogenic media from Dec.2024 to Jan.2025,the strains were isolated,and the targeted strains were identified by matrix-assisted laser desorption/ionization time-of-flight(MALDI-TOF)mass spectrometer.RESULTS A total of 653 samples were collected in the survey,76 of which were positive for bacterial culture,60 were detected with CRGNB,and the isolation rate of CRGNB was 9.19％.The isolation rate of CRGNB was 53.40％in the water-source group,0.91％in the non-water-source group,and there was significant difference(x2=286.450,P＜0.001).The result of whole genome sequencing for 17 strains of CRKP showed that ST11 and ST15 were the two major types of multilocus typing(MT),respective-ly carrying 2-12 types of drug resistance genes.CONCLUSIONS The CRGNB strains are detected in some environ-mental sites of the ICUs of 15 tertiary hospitals in Shanghai,and the isolation rate of CRKP is highest among them.The colonization rate of CRGNB is relatively low on the highly frequent-contact object surfaces of the ICUs,however,sink drain holes poses a risk of hospital-acquired CRGNB infections transmissions.Additionally,the ba-sins and towels of the CRGNB patients are hard to be thoroughly cleaned,disinfected and dried,resulting in a high contamination rate.

In magnetic resonance examination,the interaction between implants and the radio frequency(RF)fields induces heating in human tissue and may cause tissue damage.To assess the RF-induced heating of implants,three steps should be executed,including electromagnetic model construction,electromagnetic model validation,and virtual human body simulations.The crucial step of assessing RF-induced heating involves the construction of a test environment for electromagnetic model validation.In this study,a hardware environment,comprised of a RF generation system,electromagnetic field measurement system,and a robotic arm positioning system,was established.Furthermore,an automated control software environment was developed using a Python-based software development platform to enable the creation of a high-precision automated integrated test environment.The results indicate that the electric field generated in this test environment aligns well with the simulated electric field,making it suitable for assessing the RF-induced heating effects of implants.

This paper investigates the mechanism of radio-frequency(RF)heating that occurs when two adjacent orthopedic implants are present together under magnetic resonance imaging(MRI)at 1.5 Tesla and 3.0 Tesla.When a patient has multiple implants close to each other,interactions between the implants may increase RF heating.Typical generic interlocking plate and antibiotic nail implants are adopted as examples.To analyze the effect of adjacent implants,the amplitude and direction of incident and scattering vector electric fields at the hot spot position are calculated and extracted using numerical simulation based on Huygens principle.It is shown that a strong coupling effect occurs due to the existence of both the incident field and a strong scattering field.Huygens principle can be used to obtain the first and second order scattering fields generated between implants.If the first-and second-order electric field terms are summed within a certain region,the RF-induced heating of this dual-implant system increases.

In MRI examination, RF heating of implants will affect the safety of implant wearers. The conductivity of various tissues in the human body is significantly different, and the medium conductivity will affect the distribution of the RF electric field. Therefore, it is necessary to study the RF heating of different medium conductivity. Based on the analysis of the principle of MRI RF heating, this study build the model of the bird cage coil, ASTM standard phantom and lead, and the conductivity of several typical human tissues is selected as the conductivity in the experiment. Then calculate the power deposition of the lead at 64 MHz. The results show that the medium conductivity has no effect on the distribution of electric field and power deposition, and the hot spot distribution remains unchanged under different conductivity; The smaller the conductivity is, the larger the power deposition of the lead is, and the greater the temperature rise of the lead caused by RF heating is; The change of conductivity and power deposition is approximately linear. At the limit of 2 W/kg whole body specific absorption rate(SAR), the conductivity decreases, and the wire power deposition increases sharply.

Objective:To establish a multilocus sequence typing (MLST) assay for Corynebacterium ( C.) striatum, explore the population structure and evolution relationship of clinical isolates of C. striatum. Methods:Seven housekeeping genes ( gyrA, gyrB, hsp65, sodA, secA1, rpoB, 16S rRNA) were amplified with PCR by using self-designed specific primers and sequenced. Then, the sequences were assembled with software SeqMan. The gene diversity and gene recombination characteristics were evaluated by using software DnaSP 5.10.01 and Splits tree 4.14.2. The phylogenetic tree and the minimum spanning tree were constructed based on the sequence types (ST) characteristics by using software MEGA 7.0.14 and BioNumerics, respectively. In addition, the genetic evolutionary relationship among STs were analyzed by using software eBURST 3.0. Results:The expected amplification products of seven sites selected in all the test strains were obtained. Splits tree showed that the clustering of all C. striatum strains was consistent, suggesting that gene recombination is the potential driving force for the evolution of C. striatum. All of the 344 C.striatum strains were divided into 72 STs by MLST and 85.7% of the strains formed clonal complexes. CC19 was the predominant clonal complex, whereas ST16 in the clonal complex was detected in the most strains. ST had a certain geographic clustering and a certain correlation with the isolation time. Conclusions:C. striatum showed high genetic diversity in China and CC19 was the predominant clonal complex. The MLST assay established in this study can be used for the typing of C. striatum, but further improvement is needed.

ABSTRACT OBJECTIVE：To compare the effectiveness and economics of peramivir and oseltamivir in the treatment of influenza complicated with febrile seizures in children. METHODS：In retrospective study，152 children with influenza complicated with febrile seizures were collected from our hospital during Dec. 2018 to Mar. 2019.They were divided into peramivir group（81 cases） and oseltamivir group （71 cases）. Fever remission time， medication duration， hospital duration， clinical efficacy （determined by convulsion，cough，nasal obstruction，runny nose，sore throat，etc.），the incidence of rash，the number of children with combined antibiotic and TCM were compared between 2 groups. Cost-effectiveness analysis was used to evaluate cost-effectiveness ratio（CER）and incremental cost-effectiveness ratio（ICER）of medication regimen in 2 groups. The sensitivity analysis of the effect and total cost were carried out with Logistic regression and multiple linear regression respectively through CER and ICER calculated by reducing 15％ drug price. RESULTS：There was no statistical significance in fever remission time， medication duration，hospitalization duration，the incidence of rash and proportion of children with combined antibiotics between 2 groups（P＞0.05）. There was statistical significance in proportion of children with combined TCM and clinical effect，and the proportion of children with combined TCM in peramivir group was significantly lower than oseltamivir group（P＜0.001）. Clinical effect of peramivir group was significantly better than that of oseltamivir group（P＝0.021）. Total cost of peramivir group and oseltamivir group were 5 442.84 yuan/person and 5 571.71 yuan/person（P＝0.795）；CER of them were 54.47 and 56.51；ICER of peramivir group was － 89.38. The results of sensitivity analysis were consistent with those of basic analysis.CONCLUSIONS： Compared with oseltamivir，peramivir is more effective and less costly for children with influenza and febrile seizures.

The complex electromagnetic field environments in magnetic resonance imaging system(MRI) can have a significant impact on patients carrying implants, the RF heating problems being particularly important. To ensure the safety of the patients, it is necessary to understand the distribution of tissue temperature in the MRI environment and its changes over time. Based on the analysis of tissue temperature rise in MRI, this paper constructs a bird cage coil for generating RF field in MRI system, and constructs ASTM standard/improved phantom and single-cavity pacemaker finite element models, use time-domain finite difference (FDTD) to simulate. Firstly, the correctness of the simulation software and simulation method was validated according to the method of ISO. Then the distribution of the electric field, SAR and temperature field and the temperature change with time were calculated in the environment of 64 MHz, 2 W/kg. The difference in temperature rise with blood heat exchange and no blood heat exchange (standard/improved phantom) was specifically compared. The simulation results show that there are electric field and SAR hotspots near the electrode tip, the wire tail and the case of pacemaker. There are high SAR values on both sides of the phantom, and the shorter the distance from the coil, the higher the SAR. The temperature field distribution is similar to the SAR distribution; the temperature is higher in the area around the end of the wire and the case of pacemaker because the heat accumulation is higher around this area. At the same time, blood heat exchange can reduce the temperature rise to a certain extent.
Electromagnetic Fields ; Humans ; Magnetic Resonance Imaging ; Models, Theoretical ; Phantoms, Imaging ; Prostheses and Implants ; Temperature