1.Improvement on DNA extraction method of methicillin resistant Staphylococcus aureus
Shu JIN ; Yuhan ZOU ; Peiyi YAN ; Dekui HUANG ; Ji ZHANG
International Journal of Laboratory Medicine 2016;(3):303-304
Objective To study a nucleic acid extraction method suitable for detecting methicillin‐resistant Staphylococcus aureus (MRSA) by PCR method .Methods Under different incubation conditions ,MRSA was cracked by lysozyme ,lysostaphin or chel‐ex100R resin for obtaining DNA ,then the target gene was detected by using the PCR method .Results DNA was obtained by sim‐ultaneously using lysozyme ,lysostaphin and chelex100R resin solution ,the obtained Ct value was significantly lower than that of the other components of schizolysis solutions when PCR was used to detect mecA gene of obtained DNA .There was no statistically sig‐nificant difference between adopting the 56 ℃ one‐step method and the 37 ℃ and 56 ℃ two‐step method for conducting MRSA schizolysis(P> 0 .05) ,but the steps were simplified .Conclusion Incubating MRSA in solution containing lysozyme ,lysostaphin , chelex100R resin for 30 min at 56 ℃ is the convenient and efficient schizolysis method to extract DNA ,which can be used immedi‐ately for the next step of PCR and lays the foundation for PCR rapid detection of clinical MRSA infection .
2.Drug resistance analysis and Staphylococcal cassette chromosome SCCmec genotypes of methicillin resistant Staphylococcus aureus
Yuhan ZOU ; Qingzhong LIU ; Ji ZHANG ; Lingqin ZHOU ; Chao CHEN ; Peiyi YANG ; Shu JIN
International Journal of Laboratory Medicine 2018;39(2):159-162
Objective To investigate the drug resistance situation and Staphylococcal cassette chromosome mec(SCCmec) genotypes of methicillin resistant Staphylococcus aureus (M RSA ) strains isolated from Shang-hai Putuo District People′s Hospital in order to provide a theoretical basis for predicting the trend of drug re-sistant bacterial strains and clinical treatment and prevention of MRSA .Methods Three hundreds and eighty clinically isolated MRSA strains in this hospital were collected from January 2012 to December 2016 .The in vitro drug susceptibility test was performed by adopting the broth microdilution method .The SCCmec geno-types were examined by adopting the multiplex polymerase chain reaction .Results All strains were sensitive to linezolid and vancomycin ,the sensitivity rate was 100 .0% ;the resistance rates to rifampicin and cotrimox-azole were lower ,which were 5 .0% and 7 .6% respectively ;but the strains were highly resistant to erythromy-cin ,levofloxacin and tetracycline ,with the resistance rate of 100 .0% ,94 .2% ,93 .4% and 90 .0% .The resist-ance rate to penicillin was 100 .0% .Among 380 strains of MRSA ,there were 281 strains(73 .9% ) of SCCmecⅡ ,59 strains (15 .5% ) of SCCmecⅢand 5 strains (1 .3% ) of SCCmecⅣa ,other 35 strains(9 .2% ) of MRSA could not be classified .Conclusion M RSA strains isolated in the Shanghai Putuo District People′s Hospital are mainly the type SCCmecⅡ ,w hich has the multi-drug resistant characteristics ,and the drug resistance spec-trum of different SCCmec genotypes is different .
3.Research progress in the treatment of primary insomnia with electroacupuncture
Liang GUO ; Yufeng BI ; Changchun JI ; Zhangyin SUN ; Hui SUN ; Yuhan XUE
International Journal of Traditional Chinese Medicine 2023;45(3):381-384,F4
Electroacupuncture treatment of primary insomnia is widely used and with confirmed efficacy. The factors influencing the therapeutic effect of electroacupuncture include waveform selection, treatment frequency, stimulation intensity, stimulation time and acupoint selection. The mechanism of electroacupuncture in treating this disease mainly includes regulating the levels of excitatory neurotransmitters, γ-aminobutyric acid, melatonin and interleukin cytokines.
4.Study of event-related potentials in school-age children with cleft palate
SHU Huang ; YANG Feng ; WANG Ji ; XIAO Yuhan ; DING Guicong
Journal of Prevention and Treatment for Stomatological Diseases 2018;26(4):236-239
Objective :
To investigate possible functional disorders of central auditory processing and language in school-age children with cleft palate through an assessment of the characteristics of the P300 and N400 event-related potentials (ERPs).
Methods :
This study included 28 school-age children with cleft palate, aged 6 to 12 years, and 30 children without cleft palate as a control group. The P300 and N400 ERPs were selected as indexes of the central auditory processing and language functions of children in both groups. The data were statistically compared between the two groups.
Results :
Compared with the controls, the children with cleft palate showed a significantly prolonged P300 latency (331.73 ± 14.94 ms vs. 348.64 ± 14.66 ms, P < 0.05) and a significantly decreased P300 amplitude (13.47 ± 2.24 μV vs. 12.07 ± 2.46 μV, P < 0.05). Similarly, the N400 latency of children with cleft palate was significantly prolonged compared to that of controls (431.07 ± 17.90 ms vs. 408.23 ± 18.04 ms, P < 0.05), and the N400 amplitude was significantly decreased compared to that of controls (13.75 ± 2.12 μV vs. 15.17 ± 2.34 μV, P < 0.05).
Conclusion
School-age children with cleft palate may have central auditory processing disorders and language dysfunctions.
5.Study on source thickness and counting efficiency calibration for determining gross alpha activity in drinking water
Yuxin QIAN ; Liangliang YIN ; Yuhan XIE ; Yanqin JI
Chinese Journal of Radiological Medicine and Protection 2021;41(12):937-940
Objective:To study the influence of source thickness and counting efficiency calibration on the measurement of gross alpha activity in water.Methods:241Am and natural uranium reference materials were spiked in drinking water to prepare source on a planchet with different thickness, for counting alpha activity on the planchet. Results:The effective thickness measured by spiking 241Am or uranium standard solution in water sample was consistent with the empirical value of 4 mg/cm 2. The alpha counting rate was in a linear increase trend from 2A-5A mg/cm 2 and was basically stable and no longer increase when thickness was higher than 10A mg/cm 2 (A was area of planchet). The result calculated by effective thickness method and thick source method were in good agreement when thickness was 10A mg/cm 2. Conclusions:In order to reduce the deviation of gross alpha counting rate caused by the source thickness and counting efficiency calibration, the source thickness is recommended to be 10A mg/cm 2.
6. Application of multiplex PCR assay to study early multiple herpesviruses infection during HSCT
Yuhan JI ; Ziling ZHU ; Lulu YANG ; Yiyu XIE ; Jia CHEN ; Hong LIU ; Xiao MA ; Yuejun LIU ; Jun HE ; Yue HAN ; Depei WU ; Xiaojin WU
Chinese Journal of Hematology 2019;40(2):125-131
Objective:
To investigate herpesvirus infection in early stage of hematopoietic stem cell transplantation (HSCT) by multiplex polymerase chain reaction (PCR), and to explore the association between multiple herpesviruses infection and clinical characteristics in HSCT patients and its impact on post-transplant complications and prognosis.
Methods:
A total of 734 peripheral blood samples were collected from 90 patients undergoing HSCT in the Department of Hematology, the First Affiliated Hospital of Soochow University between February 2017 and August 2017. The peripheral blood specimens were obtained before and within 90 days after transplantation at different time points. Lab-Aid824 Nucleic Acid Extraction Mini Reagent was used to extract DNA and multiplex PCR assay was used to simultaneously detect 8 kinds of human herpesviruses from genomic DNA. The incidence of various herpesvirus infections, its correlation with clinical features and effects on post-transplant complications and prognosis were analyzed.
Results:
The median follow-up time was 192 (range: 35-308) days. Among the 90 patients before transplantation, the incidence of herpes virus infection was 35.6% (32/90), including 12.2% (11/90) with one herpes virus infection and 23.3% (21/90) with multiple viruses infection. The incidence of herpes virus infection after transplantation was 77.8% (70/90), including 20.0% (18/90) with one herpes virus infection and 57.8% (52/90) with multiple herpes virus infection. Among the 52 patients with multiple herpes viruses infection, 30 (57.7%) patients were infected by 2 kinds of viruses, 18 (34.6%) patients by 3 kinds of viruses and 4 (7.7%) patients by 4 kinds of viruses. There was a correlation between HHV-6 and HHV-7 herpesvirus infection (
7.Evaluation of influencing factors and uncertainty of detection of trace uranium in drinking water using ultraviolet fluorescence
Yuhan XIE ; Liangliang YIN ; Yuxin QIAN ; Tingting XIA ; Yanqin JI
Chinese Journal of Radiological Medicine and Protection 2022;42(4):291-296
Objective:To achieve rapid and accurate detection of trace uranium in drinking water by analyzing the factors influencing the accuracy of uranium measurement in drinking water using ultraviolet fluorescence method and by evaluating the uncertainty in measurement.Methods:The influence of acidity, Fe 3+ and Mn 2+ contents on the analitical result were studied to optimize the measurement conditions. The accuracy of the measurement method was verified in 7 laboratories. By studying the errors introduced in the process of standard preparation, sample pretreatment and measurement, the sources of uncertainty were analyzed and the uncertainty was synthesized. Results:At pH 1-11 in aqueous solution, the linear regression coefficient of the standard curve was greater than 0.995, which was in line with the linear measurement range of the instrument. At pH 12 or so, the linear regression coefficient was 0.761, which could not meet the measurement requirements. At pH<3 or pH>10, the increase in fluorescence count was lower, which might increase the measurement error. At Fe 3+ concentration ≥15 mg/L, a large deviation occurred in measurement value that could affect seriously measurement result. At Mn 2+ concentration ≥ 1.6 mg/L, the sample produced white precipitation, which could affect the measurement accuracy. Three spiked water samples with different concentrations were determined in 8 laboratories. Each water sample was measured six times in parallel. The relative standard uncertainty of the result were 6.42×10 -2, 4.48×10 -2 and 5.26×10 -2 μg/L, and the expanded uncertainties were 0.03, 0.06 and 0.12 μg/L( k=2), respectively. Conclusions:The optimum conditions for the determination of uranium in water using this method pH were in samples 3-10, the concentration of Fe 3+ less than 15 mg/L, and the concentration of Mn 2+ less than or equal to 1.6 mg/L. The main sources of uncertainty in the measurement of uranium in water using ultraviolet fluorescence method arise from the repeated measurement error and the volume of added standard solution.
8.Clinical analysis of metagenome next-generation sequencing for diagnosing invasive fungal disease in patients with early stage of hematopoietic stem cell transplantation
Yuhan JI ; Mingyue PAN ; Xiaoyu LAI ; Lizhen LIU ; Jimin SHI ; Yanmin ZHAO ; Jian YU ; Luxin YANG ; Yi LUO
Journal of Army Medical University 2024;46(4):311-318
Objective To analyze the clinical outcomes of early invasive fungal disease(IFD)in patients after allogenetic hematopoietic stem cell transplantation(allo-HCST)with metagenomic next-generation sequencing(mNGS).Methods A retrospective analysis was conducted on patients undergoing allo-HCST in our Bone Marrow Transplantation Center between July 2021 and October 2022.These patients experienced one of the following conditions within 100 d after transplantation:① Patients with persistent fever and negative blood culture after empiric antimicrobial therapy for 72 h or longer;② Hyperpyrexia of unknown origin occurred again after effective anti-infection in the past;③ Symptoms in lower respiratory tract associated with lung lesions on CT scan,and empiric anti-infective therapy was ineffective.Peripheral blood or bronchoscopic alveolar lavage fluid were tested with mNGS,and overall survival(OS)and non-relapse mortality(NRM)were analyzed.Results There were 60 patients enrolled in this study.For the peripheral blood samples of 47 cases and bronchoalveolar lavage fluid samples of 13 cases,mNGS found that 19 cases were negative to pathogens,30 cases were non-fungal positive,and 11 case were fungal positive,including 3 cases of aspergillus,5 cases of mucor,2 cases of Candida tropicalis,and 1 case of Trichosporon asahii.Of the 11 patients with fungal positive,8 achieved complete remission after antifungal therapy according to the mNGS results.The 1-year OS and NRM of the 60 patients were 70.0%(95%CI:64.1%~75.9%)and 20.0%(95%CI:11.9%~32.5%),respectively,while those of the fungal infection patients were 54.5%(95%CI:49.5%~69.5%)and 36.4%(95% CI:15.5%~70.3%),respectively.No significant differences were seen in 1-year OS(P=0.487)and 1-year NRM(P=0.358)among the negative,fungal infection and non-fungal infection patients,neither OS(P=0.238)and NRM(P=0.154)between the fungal infection and the non-fungal infection patients.Conclusion mNGS can rapidly diagnose the early IFD after allo-HSCT,which is helpful for timely and effective treatment and improves the prognosis of patients.