1.Pathogens in Urinary System:Their Distribution and Resistance Analysis
Chengling YAN ; Shuzhen FAN ; Yinfang CAO ; Fenge LI
Chinese Journal of Nosocomiology 2006;0(02):-
OBJECTIVE To study the distribution and drug resistance of pathogens in urinary system,provide the credible evidence with the clinic diagnosis and the treatment of urinary diseases,and give doctors reasonable advice for medicine usage. METHODS The pathogens from the urine specimens were isolated and cultured from the patients in hospital from Jan 2003 to Dec 2004.The total 536 strains of pathogens were identified and the drug resistance was analyzed. RESULTS Escherichia coli among the pathogens infected the urinary system rated the top(57.0%),secondly were Enterococcus,Klebsiella,Staphylococcus,Pseudomonas aeruginosa and fungi.The drug resistance of E.coli to imipenem was the lowest,about 2.6%,however,it was above 30.0% towards the most beta-lactam antibiotics;the drug resistance of Enterococcus was generally higher,about 40.0-70.0%,but vancomycin was lower,about 10.3%. CONCLUSIONS The main pathogens are Enterobacteriaceae which infect the urinary system,the drug resistance is obviously higher to the quinolones,the clinic should reasonably choose the antibiotics according to the test results of the pathogens sensitivity to drugs.
2.Safety Study of Implant Wearers in MRI RF Field Environment.
Chinese Journal of Medical Instrumentation 2020;44(2):101-107
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
3.Investigation of Coupling Effect for Adjacent Orthopedic Implants on MRI Radio-Frequency Heating
Ran GUO ; Zhichao WANG ; Jing WANG ; Chengling LI ; Yonghua LI ; Sheng HU
Chinese Journal of Medical Instrumentation 2024;48(5):478-485
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.
4.Study on RF Heating of Implants in Different Conductivity Medium.
Chengling LI ; Yonghua LI ; Sheng HU
Chinese Journal of Medical Instrumentation 2023;47(5):497-501
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.
5.Establishment and application of a multilocus sequence typing assay for Corynebacterium striatum
Chengling WANG ; Jiazheng WANG ; Zhiguo LIU ; Shuai XU ; Xiong ZHU ; Huan LI ; Xiaoxia WANG ; Xiaotong QIU ; Kongjiao WEI ; Shihong FAN ; Lichao HAN ; Zhenjun LI
Chinese Journal of Epidemiology 2021;42(9):1628-1634
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.
6.Application of evidence - based perioperative nursing in transradial interventional treatment by using sheathless guiding - catheter for coronary artery lesions
Hong YE ; Shiguang LI ; Ling XIN ; Chengling AN ; Linhui CHENG
Journal of Interventional Radiology 2018;27(3):281-284
Objective To investigate the application of evidence - based perioperative nursing in transradial interventional treatment by using sheathless guiding-catheter for coronary artery lesions. Methods The evidence-based nursing team researched for the relevant literature and evidences. According to the theory of critical evidence - based nursing, evidence - based perioperative nursing measures were carried out for 30 patients with coronary artery diseases who were receiving transradial interventional treatment by using sheathless guiding-catheter. Results The success rate of puncturing was 100%. After the procedure only two patients developed radial artery complications, and after promptly treatment no severe consequences occurred. The treatment achieved the desired clinical results. Conclusion Evidence-based nursing measures can regulate nursing behavior, and presciently make the nursing work in a standardized and sequenced way, thus, the nursing work is changed from the passive mode to an active mode. Therefore, evidence - based perioperative nursing is worth of clinical application(J Intervent Radiol, 2018, 27:281 -284)
7.Research on Construction of Test Environment for Assessment of RF-Induced Heating Effects of Implants
Yonghua LI ; Lingfeng LU ; Jing WANG ; Chengling LI ; Pengfei YANG ; Zhichao WANG ; Dajing WU ; Xun LIU ; Sheng HU
Chinese Journal of Medical Instrumentation 2024;48(3):281-284,297
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.
8.Perioperative bundle of cares for patients receiving His bundle pacing or para-His bundle pacing
Hong YE ; Jun ZHANG ; Ling XIN ; Tingye HU ; Chengling AN ; Linghui CHENG ; Yanhong LI ; Mingfeng WANG
Journal of Interventional Radiology 2017;26(12):1143-1146
Objective To explore the optimal perioperative nursing program for patients receiving cardiac pacemaker by His bundle pacing or by para-His bundle pacing.Methods A total of 26 patients,who were receiving cardiac pacemaker by His bundle pacing or by para-His bundle pacing,were enrolled in this study.The bundle of cares,used as the nursing intervention measures,was executed in all patients,which included strengthening the professional training for specialist team members,improvement of preoperative intervention,careful intraoperative cooperation,postoperative observation of patient's condition and complications,prevention and health guidance,etc.Results Through the strict implementation of the special bundle of nursing cares,all the 26 patients could well cooperated with surgical procedure,and after the treatment the patients recovered smoothly and achieved the desired results with no occurrence of complications.Conclusion The intervention measures of the bundle of cares are scientific and reasonable.The implementation of the special bundle of nursing cares can promote the professional nursing ability of nurses and ensure the quality of nursing service.
9.Pharmacoeconomic Evaluation of Peramivir versus Oseltamivir in the Treatment of Influenza Complicated with Febrile Seizures for Children
Shengjie CHEN ; Meixian XU ; Chengling LI ; Lei DONG ; Zhihua AN
China Pharmacy 2020;31(1):75-80
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.