1.Assessment of respiratory protection competency of staff in healthcare facilities
Hui-Xue JIA ; Xi YAO ; Mei-Hua HU ; Bing-Li ZHANG ; Xin-Ying SUN ; Zi-Han LI ; Ming-Zhuo DENG ; Lian-He LU ; Jie LI ; Li-Hong SONG ; Jian-Yu LU ; Xue-Mei SONG ; Hang GAO ; Liu-Yi LI
Chinese Journal of Infection Control 2024;23(1):25-31
Objective To understand the respiratory protection competency of staff in hospitals.Methods Staff from six hospitals of different levels and characteristics in Beijing were selected,including doctors,nurses,medical technicians,and servicers,to conduct knowledge assessment on respiratory protection competency.According to exposure risks of respiratory infectious diseases,based on actual cases and daily work scenarios,content of respira-tory protection competency assessment was designed from three aspects:identification of respiratory infectious di-seases,transmission routes and corresponding protection requirements,as well as correct selection and use of masks.The assessment included 6,6,and 8 knowledge points respectively,with 20 knowledge points in total,all of which were choice questions.For multiple-choice questions,full marks,partial marks,and no mark were given respective-ly if all options were correct,partial options were correct and without incorrect options,and partial options were correct but with incorrect options.Difficulty and discrimination analyses on question of each knowledge point was conducted based on classical test theory.Results The respiratory protection competency knowledge assessment for 326 staff members at different risk levels in 6 hospitals showed that concerning the 20 knowledge points,more than 60%participants got full marks for 6 points,while the proportion of full marks for other questions was relatively low.Less than 10%participants got full marks for the following 5 knowledge points:types of airborne diseases,types of droplet-borne diseases,conventional measures for the prevention and control of healthcare-associated infec-tion with respiratory infectious diseases,indications for wearing respirators,and indications for wearing medical protective masks.Among the 20 knowledge questions,5,1,and 14 questions were relatively easy,medium,and difficult,respectively;6,1,4,and 9 questions were with discrimination levels of ≥0.4,0.30-0.39,0.20-0.29,and ≤0.19,respectively.Conclusion There is still much room for hospital staff to improve their respiratory protection competency,especially in the recognition of diseases with different transmission routes and the indications for wearing different types of masks.
2.Application of Acoustoelectric Imaging in Biological Current Detection
Yi-Jie ZHOU ; Yi-Bo SONG ; Xi-Zi SONG ; Feng HE ; Dong MING
Progress in Biochemistry and Biophysics 2024;51(5):1134-1146
The conventional noninvasive biological current detection such as electrocardiogram, electroencephalography and surface electromyography can provide electrical reference for diseases diagnosis. Because the bioelectrical signals are the mixed result of the common discharge of sell populations, the spatial resolution of the above bioelectrical detection is relatively limited. In recent years, the acoustoelectric imaging (AEI) has been introduced to spatially code biological current through noninvasive focused ultrasound. Then the electrical signal with precise focus position can be obtained. It can achieve noninvasive detection of biological electrical signals with millimeter-level spatial resolution and millisecond-level temporal resolution which is expected to develop into a new imaging technology for accurately detecting deep electrical activities of living organisms. We firstly describe AEI principle, including acoustoelectric effect and the derivation of acoustoelectric signal equation. Then we briefly introduce characteristics of acoustoelectric signal. It can be seen from the equation of acoustoelectric signal that the acoustoelectric signal depends on the current field and the ultrasonic field. Furtherly, the typical studies of AEI are introduced including acoustoelectric coupling mechanism, AEI methods, acoustoelectric brain imaging (ABI) and acoustoelectric cardiac imaging (ACI). In terms of the acoustoelectric coupling mechanism, the researchers found that the acoustoelectric effect of electrolyte solution is caused by the change of ion molar concentration, ion migration rate and ion viscosity with pressure and temperature, and the acoustoelectric effect coefficient of normal saline is accurate to (0.034±0.003)% MPa–1. In terms of AEI methods, researchers improved the detection sensitivity, spatial resolution, signal to noise ratio and other performance indicators by improving AEI methods and optimizing AEI systems. In terms of ABI, it can utilize the acoustoelectric coupling mechanism to endow the target area with spatial features of ultrasound, and achieve noninvasive high resolution EEG detection. We review the important research achievements and significance layer by layer from the perspectives of feasibility verification, method system optimization, and clinical application exploration in acoustoelectric imaging. In terms of ACI, it can be used to quantitatively evaluate the spatial distribution and dynamic changes of cardiac current field, providing a new idea for real-time monitoring of cardiac electrophysiological state before and after surgery. We summarize and review the important research achievements and significance of ACI at each stage: in phantom, in vitro and in vivo. Finally, we discuss the future research direction by focusing on the challenges faced by key technical links such as focused ultrasound targeting, ultrasonic spatial coding and decoding, acoustoelectric sensing detection, and imaging system integration, in order to provide basis and inspiration for AEI technology system and clinical transformation.
3.Mechanisms of resistance to ceftazidime/avibactam of carbapenem-resis-tant Klebsiella pneumoniae
Xi-Yuan CHEN ; Zi-Ling WANG ; Shuang SONG ; Bo-Yin XU ; Jing-Fang SUN ; Shu-Long ZHAO ; Hai-Quan KANG
Chinese Journal of Infection Control 2024;23(11):1365-1372
Objective To explore the molecular epidemiological characteristics of carbapenem-resistant Klebsiella pneumoniae(CRKP),and reveal its mechanism of resistance to ceftazidime/avibactam(CZA).Methods CZA-re-sistant CRKP strains initially isolated from the Affiliated Hospital of Xuzhou Medical University from January 2021 to September 2023 were collected.The carriage of 5 carbapenemase genes(blaKPC,blaNDM,blaOXA,blaVIM,blaIMp)were detected with gene amplification method and colloidal gold method.The relative copy number and expression level of Klebsiella pneumoniae(KP)carbapenemase-producing KP(KPC-KP)was detected with real-time quantita-tive polymerase chain reaction(RT-qPCR),mutation sites of KPC mutation strains were analyzed with whole-ge-nome sequencing,and epidemic characteristics of CRKP and resistance mechanism to CZA were analyzed.Results A total of 73 CZA-resistant CRKP strains were isolated,with 37(50.68%)being KPC and NDM co-producing strains,33(45.21%)NDM-producing alone(23 strains producing NDM-5 and 10 strains producing NDM-1),and 3 KPC-producing alone.KP-2842 strain was identified as ST11-type KPC-33 variant,KP-2127 and KP-2189 strains produced KPC-2.Compared with KP ATCC BAA-1705,the copy number of blaKPC in these strains up-regulated by 1.04-3.86 fold,and the expression increased by 6.66-12.93 fold,respectively.Colloidal gold and PCR methods demonstrated good consistency and the ability to detect the enzyme co-producing and KPC-33 variant.Conclusion In this hospital,the resistance of CRKP to CZA is primarily mediated by the metalloenzyme NDM,with co-produc-tion of NDM and KPC being a characteristic of CRKP.High copy number and expression level of blaKPC-2 also con-tribute to CZA resistance.This study identified the KPC-33 variant for the first time in ST11-type CRKP in Jiangsu Province.
4.Prediction and identification of B-cell epitopes of SARS-CoV-2 E protein
Peng-Fei ZHANG ; Jun LIU ; Zi-Yang ZOU ; Xi-Long KANG ; Li SONG ; Xin-An JIAO ; Chuang MENG ; Zhi-Ming PAN
Chinese Journal of Zoonoses 2024;40(9):807-813
This work was aimed at predicting and verifying B-cell epitopes of SARS-CoV-2 E protein through bioinformatics methods,and clarifying the dominant B cell epitopes with mouse polyclonal antibody serum prepared through SARS-CoV-2 re-combinant E protein immunization and human positive serum vaccinated with inactivated SARS-CoV-2 vaccine.The structural and B-cell linear epitopes of SARS-CoV-2 E protein were predicted with SOPMA,Expasy,SWISS-MODEL,IEDB database,and Bepid-2.0 software.Candidate epitopes were expressed as GST-tagged recombinant protein fragments in an E.coli sys-tem,and their immunoreactivity with mouse and human poly-clonal positive serum against SARS-CoV-2 E protein was de-tected by western blotting and indirect ELISA,respectively.The epitope prediction results showed that E protein contained linear B cell epitopes Ser6-Val14 and Tyr57-Pro71,and the conformational epitopes of Glu8-Val12,Leu39-Tyr59,and Ser60-Leu65.The GST tagged recombinant E protein fragments of E1 and E3,containing Ser6-Val14 and Tyr57-Pro71 epitopes,respectively,as well as E2 without an epitope sequence as a control,were expressed in an E.coli expression system and successfully purified with an Ni-NTA column.Western blotting and indirect ELISA analysis indicated that all mouse and human SARS-CoV-2 positive sera positively reacted with only E1 and E3 proteins,but negatively reacted with E2 protein,thus indicating that the corresponding epitope prediction with Ser6-Val14 and Tyr57-Pro71 was correct.This study successfully predicted and preliminarily identified two linear B cell epitopes of SARS-CoV-2 E protein,thus providing a reference for the preparation of new coronavirus vaccines and the analysis of immune response characteristics.
5.Catheter ablation versus medical therapy for atrial fibrillation with prior stroke history: a prospective propensity score-matched cohort study.
Wen-Li DAI ; Zi-Xu ZHAO ; Chao JIANG ; Liu HE ; Ke-Xin YAO ; Yu-Feng WANG ; Ming-Yang GAO ; Yi-Wei LAI ; Jing-Rui ZHANG ; Ming-Xiao LI ; Song ZUO ; Xue-Yuan GUO ; Ri-Bo TANG ; Song-Nan LI ; Chen-Xi JIANG ; Nian LIU ; De-Yong LONG ; Xin DU ; Cai-Hua SANG ; Jian-Zeng DONG ; Chang-Sheng MA
Journal of Geriatric Cardiology 2023;20(10):707-715
BACKGROUND:
Patients with atrial fibrillation (AF) and prior stroke history have a high risk of cardiovascular events despite anticoagulation therapy. It is unclear whether catheter ablation (CA) has further benefits in these patients.
METHODS:
AF patients with a previous history of stroke or systemic embolism (SE) from the prospective Chinese Atrial Fibrillation Registry study between August 2011 and December 2020 were included in the analysis. Patients were matched in a 1:1 ratio to CA or medical treatment (MT) based on propensity score. The primary outcome was a composite of all-cause death or ischemic stroke (IS)/SE.
RESULTS:
During a total of 4.1 ± 2.3 years of follow-up, the primary outcome occurred in 111 patients in the CA group (3.3 per 100 person-years) and in 229 patients in the MT group (5.7 per 100 person-years). The CA group had a lower risk of the primary outcome compared to the MT group [hazard ratio (HR) = 0.59, 95% CI: 0.47-0.74, P < 0.001]. There was a significant decreasing risk of all-cause mortality (HR = 0.43, 95% CI: 0.31-0.61, P < 0.001), IS/SE (HR = 0.73, 95% CI: 0.54-0.97, P = 0.033), cardiovascular mortality (HR = 0.32, 95% CI: 0.19-0.54, P < 0.001) and AF recurrence (HR = 0.33, 95% CI: 0.30-0.37, P < 0.001) in the CA group compared to that in the MT group. Sensitivity analysis generated consistent results when adjusting for time-dependent usage of anticoagulants.
CONCLUSIONS
In AF patients with a prior stroke history, CA was associated with a lower combined risk of all-cause death or IS/SE. Further clinical trials are warranted to confirm the benefits of CA in these patients.
6.Research progress of respiratory syncytial virus (RSV) infection and respiratory diseases in infancy.
Xi-Zi DU ; Shuang SONG ; Xiao-Qun QIN ; Yang XIANG ; Xiang-Ping QU ; Hui-Jun LIU ; Chi LIU
Acta Physiologica Sinica 2021;73(6):1043-1053
Lower respiratory tract infection (LRTI) induced by respiratory syncytial virus (RSV) is an important cause of hospitalization for infants. Compared with adults, infants are more likely to cause serious respiratory diseases after RSV infection due to the specific immature airway structure and immune system. The balance of immune resistance and immune tolerance of the host is critical to effective virus clearance and disease control. This paper reviews the relationship between RSV infection and respiratory diseases in infancy, the influence factors of the high pathogenicity of RSV infection in early life, as well as the research progress of anti-RSV therapy, and expands the specific molecular events regulating immune resistance and immune tolerance. We expect to present new ideas for the prevention and treatment of RSV-related respiratory diseases in clinical practice.
Humans
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Infant
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Respiration Disorders
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Respiratory Syncytial Virus Infections
;
Respiratory Syncytial Viruses
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Respiratory Tract Infections
7.Genetic factors related to the widespread dissemination of ST11 extensively drug-resistant carbapenemase-producing Klebsiella pneumoniae strains within hospital.
Dai-Xi LI ; Yao ZHAI ; Zhao ZHANG ; Ya-Tao GUO ; Zhan-Wei WANG ; Zi-Long HE ; Song-Nian HU ; Yu-Sheng CHEN ; Yu KANG ; Zhan-Cheng GAO
Chinese Medical Journal 2020;133(21):2573-2585
BACKGROUND:
Carbapenemase-producing Klebsiella pneumoniae (CP-Kp) poses distinct clinical challenges due to extensively drug resistant (XDR) phenotype, and sequence type (ST) 11 is the most dominant blaKPC-2-bearing CP-Kp clone in China. The purpose of this current retrospective study was to explore the genetic factors associated with the success of XDR CP-Kp ST11 strains circulated in the intensive care unit (ICU) of a Chinese tertiary hospital.
METHODS:
Six ST11 XDR CP-Kp strains were identified between May and December 2014 and validated by minimum inhibitory concentration examination, polymerase chain reaction, and pyrosequencing. The six ST11 XDR CP-Kp, as well as three multi-drug resistant (MDR) and four susceptible strains, were sequenced using single-molecule real-time method. Comprehensively structural and functional analysis based on comparative genomics was performed to identify genomic characteristics of the XDR ST11 CP-Kp strains.
RESULTS:
We found that ST11 XDR blaKPC-2-bearing CP-Kp strains isolated from inpatients spread in the ICU of the hospital. Functionally, genes associated with information storage and processing of the ST11 XDR CP-Kp strains were more abundant than those of MDR and susceptible strains, especially genes correlative with mobile genetic elements (MGEs) such as transposons and prophages. Structurally, eleven large-scale genetic regions taken for the unique genome in these ST11 XDR CP-Kp strains were identified as MGEs including transposons, integrons, prophages, genomic islands, and integrative and conjugative elements. Three of them were located on plasmids and eight on chromosomes; five of them were with antimicrobial resistance genes and eight with adaptation associated genes. Notably, a new blaKPC-2-bearing ΔΔTn1721-blaKPC-2 transposon, probably transposed and truncated from ΔTn1721-blaKPC-2 by IS903D and ISKpn8, was identified in all six ST11 XDR CP-Kp strains.
CONCLUSION
Our findings suggested that together with clonal spread, MGEs identified uniquely in the ST11 XDR CP-Kp strains might contribute to their formidable adaptability, which facilitated their widespread dissemination in hospital.
Anti-Bacterial Agents
;
Bacterial Proteins
;
China
;
Electrophoresis, Gel, Pulsed-Field
;
Hospitals
;
Humans
;
Klebsiella Infections/drug therapy*
;
Klebsiella pneumoniae/genetics*
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Microbial Sensitivity Tests
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Multilocus Sequence Typing
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Pharmaceutical Preparations
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Retrospective Studies
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beta-Lactamases/genetics*
8.Effect of Overexpressed Senescence Marker Protein 30 in Human Lens Epithelial Cell Line SRA01/04 under High-Calcium Mediated Oxidative Stress
Song-man LI ; Xi CHEN ; Zi-hao HAN ; THU THU WIN AINT ; Xin ZHONG ; Dong-yong TANG ; Hao LIANG
Journal of Sun Yat-sen University(Medical Sciences) 2019;40(1):54-61
【Objective】To explore the effects of overexpressed senescence marker protein 30 (SMP30) on cell proliferation and antioxidative activity in human lens epithelial cell(HLEC)line SRA01/04 under high-calcium mediated oxidative stress. 【Methods】There were 3 groups in this experiment:SMP30 overexpressed group (OE,experimental group),NCOE group (negative control group) and SRA01/04 group (blank control group). OE and NCOE lentiviral vectors were used to transfect SRA01/04 respectively. A high- calcium- mediated- stress cell model was established by culturing cells with medium containing 15 mmol/L CaCl2 for 24 h. BrdU assay was used to measure cell proliferation. SOD assay kit and GSSG/T- GSH assay kit were used to detect the level of intracellular oxidative stress. 【Results】Green fluorescence protein could be observed in all transfected cell groups under fluorescence microscope and the transfection efficiency was close to 80% ,suggesting that OE cell model was constructed successfully. Under the high calcium culture conditions,the activity of relative cell proliferation and SOD in OE group[(3.89 ± 0.20)and(47.5 ± 4.3 U/mg)]were significantly higher than that in NCOE group[(2.82 ± 0.34)and(30.6 ± 4.2 U/mg)]and SRA01/04 group[(2.96 ± 0.25)and(26.8 ± 1.5 U/mg)],the ratio of GSSG/T-GSH in OE group(2.36 ± 0.51)was significantly lower than that in NCOE group(16.36 ± 2.48)and SRA01/04 group(20.12 ± 2.54)(n=3,P<0.05);there was no significant difference between NCOE group and SRA01/04 group (n=3,P>0.05). 【Conclusions】Overexpression of SMP30 increased the activity of cell proliferation and SOD,but decreased the ratio of GSSG/T- GSH in SRA01/04 cell(HLEC),indicating that SMP30 may alleviate the progression of high-calcium-mediated oxidative cell damage and possess the cytoprotective functions in HLEC.
9.MACF1 knockdown in glioblastoma multiforme cells increases temozolomide-induced cytotoxicity.
Si-di XIE ; Zi-Yang CHEN ; Hai WANG ; Min-Yi HE ; Yun-Tao LU ; Bing-Xi LEI ; He-Zhen LI ; Ya-Wei LIU ; Song-Tao QI
Journal of Southern Medical University 2017;37(9):1183-1189
OBJECTIVETo investigate the role of microtubule-actin crosslinking factor 1 (MACF1) in the response of glioma cells to temozolomide (TMZ).
METHODSTMZ was applied to a human gliomablastoma cell line (U87) and changes in the protein expression and cellular localization were determined with Western blot, RT-PCR, and immunofluorescence. The responses of the cells with MACF1 expression knockdown by RNA interference to TMZ were assessed. TMZ-induced effects on MACF1 expression were also assessed by immunohistochemistry in a nude mouse model bearing human glioblastoma xenografts.
RESULTSTMZ resulted in significantly increased MACF1 expression (by about 2 folds) and changes in its localization in the gliomablastoma cells both in vitro and in vivo (P<0.01). Knockdown of MACF1 reduced the proliferation (by 45%) of human glioma cell lines treated with TMZ (P<0.01). TMZ-induced changes in MACF1 expression was accompanied by cytoskeletal rearrangement.
CONCLUSIONMACF1 may be a potential therapeutic target for glioblastoma.
10.Effects of calcium elevation on intracellular oxidative stress in human lens epithelial cells SRA01/04
Xi CHEN ; Hao Zi HAN ; Ning Shu LI ; Man Song LI ; Wei Yan LI ; Hao LIANG
Recent Advances in Ophthalmology 2017;37(10):906-910
Objective To investigate the influence of calcium elevation on oxida tive stress in human lens epithelial cells (HLEC) SRA01/04.Method The cells (2 x 103 cells/well) which in the period of logarithmic phase were seeded into 96-well plates with three replicates for the two groups;and in the experimental group,SRA01/04 cells were exposed to a CaCI2 concentration gradient (3 mmol · L-1,5 mmol · L-1,7 mmol · L-1,9 mmol · L-1,11 mmol · L-1,13 mmol · L-1,15 mmol · L-1,17 mmol · L-1,19 mmol · L-1) for 0 h,12 h,24 h,36 h;while the cells in the control group were cultured in complete 1640 medium.Cell counting kit-8 (CCK-8) assay was used to measure cell viability.The levels of intracellular superoxide dismutase (SOD),glutathione (GSH) content and oxidized glutathione (GSSG) / total glutathione (T-GSH) were determined by using the microplate-reader method with the commercial total/oxidized glutathione and sod quantification kit.Results At first,the survival rate of SRA01/04 cells treated with 3 mmol · L-1,5 mmol · L-1,7 mmol· L-1 CaCL2 for 24 h showed a significant decrease with the increase of CaCl2 concentration by CCK-8 assays,but gradually increased when the concentration increased to 9 mmol · L-1,and the difference approached statistical significance (P < 0.05).Meanwhile,there was significant difference in the viability of the control group (0.592 + 0.055) and cells exposed to 15 mmol · L-1 CaCI2 (0.293 + 0.02) (t =7.811,P <0.05).Cell treatment with 15 mmol· L-1 CaC12 for 24 h was the most appropriate condition for HLEC apoptosis,followed by the appearance of nuclear fragmentation and dissolution,enhanced intracellular SOD viability (t =-6.417,P < 0.05),decreased T-GSH content (t =13.816,P < 0.05),and increased ratio of GSSG/T-GSH (t =-4.396,P < 0.05) when compared with the control group,and the differences were statistically significant.Conclusion Intracellular calcium elevation can inhibit the cell viability and increase the levels of SOD and GSSG in HLEC to aggravate the intracellular oxidative damage.

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