1.Evaluation on the effectiveness of comprehensive control of a bedbug infestation incident in Jiading District, Shanghai
Ping WANG ; Jie LI ; Ruhua YU ; Qiaoyan WANG ; Peisong ZHONG ; Hong YUAN ; Dongsheng RENG
Shanghai Journal of Preventive Medicine 2025;37(1):79-83
ObjectiveTo investigate the infestation of bedbugs in a staff dormitory in Jiading District, Shanghai, to explore the measures to dispose Cimex lectularius linnaeus, so as to provide a scientific basis for the prevention and control of bedbugs. MethodsThe infestation of bedbugs in the dormitory of the company was determined through field investigation, accompanied by scientific guidance under the comprehensive control measures and an effect evaluation of the control results. ResultsA total of 114 rooms distributed in 3 dormitory buildings were investigated, with an average infestation rate of 42.11%, of which building B has the highest infestation rate of 51.52%. Six bedbug specimens were collected by visual inspection in the room, and all of them were identified as Cimex lectularius linnaeus. After a series of comprehensive control measures including environmental cleanup, aerosol elimination, replacement of wooden beds with iron frame beds, and purchase of all-inclusive mattress, the bedbug infestation rate dropped to 5.26%. ConclusionComprehensive control can effectively prevent the breeding and spread of bedbugs. Dissemination and education effort should be strengthened in case of the occurrence of bedbug infestation, together with an implementation of long-term and continuous surveillance and monitoring.
2.Effect of CCNA2 on Prognosis of Colon Cancer by Regulating Immune Microenvironment of Tumor Cells
Peng YANG ; Ziyi QIU ; Lingling WANG ; Yuan HU ; Zhengzhen CHEN ; Meizhen ZHONG ; Feiyue YU ; Rongyuan QIU
Cancer Research on Prevention and Treatment 2025;52(4):305-312
Objective To investigate the relationship between cyclin A2 (CCNA2) and the prognosis of colon cancer, and its possible mechanism from the perspective of immune infiltration. Methods We downloaded the transcriptome data of colon cancer patients from The Cancer Genome Atlas database. Clinicopathological feature analysis and survival analysis were performed based on the expression levels of CCNA2. A total of 75 specimens of colon cancer and normal tissues were collected, and the expression level of CCNA2 was analyzed using immunohistochemical methods. Multivariate analysis was conducted to explore its relationship with clinicopathological features. Gene Set Enrichment Analysis (GSEA) was used to assess the potential molecular functions of CCNA2 in colon cancer. CIBERSORT algorithm was applied to calculate the correlation between CCNA2 and immune-cell infiltration in colon cancer. Results Database and immunohistochemical analyses indicated that CCNA2 was expressed at a significantly higher level in colon cancer tissues than normal tissues (P<0.001). The overall survival, disease-specific survival, and progression-free interval were all longer in the group with high CCNA2 expression than the group with low expression (all P<0.05). In tumor tissues, the expression level of CCNA2 decreased with increased pathological and TNM stages (P<0.05). The expression level of CCNA2 in normal tissues was consistently lower than that in colon cancer tissues across all clinical stages (all P<0.001). GSEA suggested that Wnt/β-catenin, KRAS, and other signaling pathways were enriched when CCNA2 was lowly expressed. CIBERSORT analysis revealed an increase in the infiltration of immune cells such as regulatory T cells and macrophages M0 when CCNA2 expression was low. Conclusion CCNA2 is highly expressed in colon cancer and closely associated with grade of pathology and TNM stage. It may recruit regulatory T cells through the KRAS and Wnt/β-catenin pathways, thereby reducing immune-cell infiltration and promoting colon cancer progression, leading to poor prognosis.
3.Process Optimization and Health Risk Assessment of Calcined Haematitum Based on QbD Concept
Yue YANG ; Jingwei ZHOU ; Jialiang ZOU ; Guorong MEI ; Yifan SHI ; Lei ZHONG ; Jiaojiao WANG ; Xuelian GAN ; Dewen ZENG ; Xin CHEN ; Lin CHEN ; Hongping CHEN ; Shilin CHEN ; Yuan HU ; Youping LIU
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(13):187-196
ObjectiveTo investigate the processing technology of calcined Haematitum based on the concept of quality by design(QbD) and to assess its health risk. MethodsTaking whole iron content, Fe2+ dissolution content and looseness as critical quality attributes(CQAs), and calcination temperature, calcination time, spreading thickness and particle size as critical process parameters(CPPs) determined by the failure mode and effect analysis(FMEA), the processing technology of calcined Haematitum was optimized by orthogonal test combined with analytic hierarchy process-criteria importance through intercriteria correlation(AHP-CRITIC) hybrid weighting method. The contents of heavy metals and harmful elements were determined by inductively coupled plasma mass spectrometry, and the health risk assessment was carried out by daily exposure(EXP), target hazard quotient(THQ) and lifetime cancer risk(LCR), and the theoretical value of the maximum limit was deduced. ResultsThe optimal processing technology for calcined Haematitum was calcination at 650 ℃, calcination time of 1 h, particle size of 0.2-0.5 cm, spreading thickness of 1 cm, and vinegar quenching for 1 time[Haematitum-vinegar(10:3)]. The contents of 5 heavy metals and harmful elements in 13 batches of calcined Haematitum were all decreased with reductions of up to 5-fold. The cumulative THQ of 2 batches of samples was>1, while the cumulative THQ of all batches of Haematitum was>1. The LCR of As in 1 batches of Haematitum was 1×10-6-1×10-4, and the LCR of the rest was<1×10-6, and the LCRs of calcined Haematitum were all<1×10-6, indicating that the carcinogenic risk of calcined Haematitum was low, but special attention should still be paid to Haematitum medicinal materials. Preliminary theoretical values of the maximum limits of Cu, As, Cd, Pb and Hg were formulated as 1 014, 25, 17, 27, 7 mg·kg-1. ConclusionThe optimized processing technology of calcined Haematitum is stable and feasible, and the contents of heavy metals and harmful elements are reduced after processing. Preliminary theoretical values of the maximum limits of Cu, As, Cd, Pb and Hg are formulated to provide a scientific basis for the formulation of standards for the limits of harmful elements in Haematitum.
4.Phase Change and Quantity-quality Transfer Analysis of Medicinal Materials, Decoction Pieces and Standard Decoction of Haliotidis Concha (Haliotis discus hannai)
Zhihan YANG ; Jingwei ZHOU ; Weichao WANG ; Yu HUANG ; Chuang LUO ; Lian YANG ; Chenyu ZHONG ; Hongping CHEN ; Fu WANG ; Yuan HU ; Youping LIU ; Shilin CHEN ; Lin CHEN
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(13):206-214
ObjectiveTo explore the quantity-quality transfer process of medicinal materials, decoction pieces and standard decoction of Haliotidis Concha(Haliotis discus hannai) by analyzing the physical phase and compositional changes, so as to provide references for the effective control of its quality. MethodsA total of 20 batches of Haliotidis Concha(H. discus hannai) from different habitats were collected and prepared into corresponding calcined products and standard decoction, and the content of CaCO3 of the three samples were determined and the extract yield and transfer rate of CaCO3 were calculated. The changes in elemental composition and their relative contents were investigated by X-ray fluorescence spectrometry(XRF), X-ray diffraction(XRD) was used to study the changes in the phase compositions of the three samples and to establish their respective XRD specific chromatogram. Fourier transform infrared spectrometry(FTIR) was used to study the changes in the chemical composition and content changes of the three samples and to establish their respective FTIR specific chromatogram, while combining hierarchical cluster analysis(HCA), principal component analysis(PCA) and orthogonal partial least squares-discriminant analysis(OPLS-DA) to find the common and differential characteristics, in order to explore the quantity-quality transfer relationship in the preparation process of standard decoction of Haliotidis Concha(H. discus hannai). ResultsThe CaCO3 contents of the 20 batches of medicinal materials, decoction pieces and standard decoction of Haliotidis Concha(H. discus hannai) were 93.87%-98.95%, 96.02%-99.97% and 38.29%-51.96%, respectively, and the extract yield of standard decoction was 1.71%-2.37%, and the CaCO3 transfer rate of decoction pieces-standard decoction was 0.68%-1.27%. XRF results showed that the elemental species and their relative contents contained in Haliotidis Concha and its calcined products had a high degree of similarity, and although there was no obvious difference in the elemental species contained in decoction pieces and standard decoction, the difference in the relative contents was obvious, which was mainly reflected in the decrease of the relative content of element Ca and the increase of the relative content of element Na. XRD results showed that Haliotidis Concha mainly contained CaCO3 of aragonite and calcite, while calcined Haliotidis Concha only contained CaCO3 of calcite, and standard decoction mainly contained CaCO3 of calcite and Na2CO3 of natrite. FTIR results showed that there were internal vibrations of O-H, C-H, C=O, HCO3- and CO32- groups in Haliotidis Concha, while O-H, HCO3- and CO32- groups existed in the calcined products and standard decoction. ConclusionThe changes of Haliotidis Concha and calcined Haliotidis Concha are mainly the increase of CaCO3 content, the transformation of CaCO3 aragonite crystal form to calcite crystal form and the absence of organic components after calcination, and the changes of calcined products and standard decoction are mainly the decrease of CaCO3 content and the increase of Na2CO3 relative content. The method established in the study is applicable to the quality control of the shellfish medicines-decoction pieces- standard decoction, which provides a new idea for the study of quality control of dispensing granules of shellfish medicines.
5.Process Optimization and Health Risk Assessment of Calcined Haematitum Based on QbD Concept
Yue YANG ; Jingwei ZHOU ; Jialiang ZOU ; Guorong MEI ; Yifan SHI ; Lei ZHONG ; Jiaojiao WANG ; Xuelian GAN ; Dewen ZENG ; Xin CHEN ; Lin CHEN ; Hongping CHEN ; Shilin CHEN ; Yuan HU ; Youping LIU
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(13):187-196
ObjectiveTo investigate the processing technology of calcined Haematitum based on the concept of quality by design(QbD) and to assess its health risk. MethodsTaking whole iron content, Fe2+ dissolution content and looseness as critical quality attributes(CQAs), and calcination temperature, calcination time, spreading thickness and particle size as critical process parameters(CPPs) determined by the failure mode and effect analysis(FMEA), the processing technology of calcined Haematitum was optimized by orthogonal test combined with analytic hierarchy process-criteria importance through intercriteria correlation(AHP-CRITIC) hybrid weighting method. The contents of heavy metals and harmful elements were determined by inductively coupled plasma mass spectrometry, and the health risk assessment was carried out by daily exposure(EXP), target hazard quotient(THQ) and lifetime cancer risk(LCR), and the theoretical value of the maximum limit was deduced. ResultsThe optimal processing technology for calcined Haematitum was calcination at 650 ℃, calcination time of 1 h, particle size of 0.2-0.5 cm, spreading thickness of 1 cm, and vinegar quenching for 1 time[Haematitum-vinegar(10:3)]. The contents of 5 heavy metals and harmful elements in 13 batches of calcined Haematitum were all decreased with reductions of up to 5-fold. The cumulative THQ of 2 batches of samples was>1, while the cumulative THQ of all batches of Haematitum was>1. The LCR of As in 1 batches of Haematitum was 1×10-6-1×10-4, and the LCR of the rest was<1×10-6, and the LCRs of calcined Haematitum were all<1×10-6, indicating that the carcinogenic risk of calcined Haematitum was low, but special attention should still be paid to Haematitum medicinal materials. Preliminary theoretical values of the maximum limits of Cu, As, Cd, Pb and Hg were formulated as 1 014, 25, 17, 27, 7 mg·kg-1. ConclusionThe optimized processing technology of calcined Haematitum is stable and feasible, and the contents of heavy metals and harmful elements are reduced after processing. Preliminary theoretical values of the maximum limits of Cu, As, Cd, Pb and Hg are formulated to provide a scientific basis for the formulation of standards for the limits of harmful elements in Haematitum.
6.Phase Change and Quantity-quality Transfer Analysis of Medicinal Materials, Decoction Pieces and Standard Decoction of Haliotidis Concha (Haliotis discus hannai)
Zhihan YANG ; Jingwei ZHOU ; Weichao WANG ; Yu HUANG ; Chuang LUO ; Lian YANG ; Chenyu ZHONG ; Hongping CHEN ; Fu WANG ; Yuan HU ; Youping LIU ; Shilin CHEN ; Lin CHEN
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(13):206-214
ObjectiveTo explore the quantity-quality transfer process of medicinal materials, decoction pieces and standard decoction of Haliotidis Concha(Haliotis discus hannai) by analyzing the physical phase and compositional changes, so as to provide references for the effective control of its quality. MethodsA total of 20 batches of Haliotidis Concha(H. discus hannai) from different habitats were collected and prepared into corresponding calcined products and standard decoction, and the content of CaCO3 of the three samples were determined and the extract yield and transfer rate of CaCO3 were calculated. The changes in elemental composition and their relative contents were investigated by X-ray fluorescence spectrometry(XRF), X-ray diffraction(XRD) was used to study the changes in the phase compositions of the three samples and to establish their respective XRD specific chromatogram. Fourier transform infrared spectrometry(FTIR) was used to study the changes in the chemical composition and content changes of the three samples and to establish their respective FTIR specific chromatogram, while combining hierarchical cluster analysis(HCA), principal component analysis(PCA) and orthogonal partial least squares-discriminant analysis(OPLS-DA) to find the common and differential characteristics, in order to explore the quantity-quality transfer relationship in the preparation process of standard decoction of Haliotidis Concha(H. discus hannai). ResultsThe CaCO3 contents of the 20 batches of medicinal materials, decoction pieces and standard decoction of Haliotidis Concha(H. discus hannai) were 93.87%-98.95%, 96.02%-99.97% and 38.29%-51.96%, respectively, and the extract yield of standard decoction was 1.71%-2.37%, and the CaCO3 transfer rate of decoction pieces-standard decoction was 0.68%-1.27%. XRF results showed that the elemental species and their relative contents contained in Haliotidis Concha and its calcined products had a high degree of similarity, and although there was no obvious difference in the elemental species contained in decoction pieces and standard decoction, the difference in the relative contents was obvious, which was mainly reflected in the decrease of the relative content of element Ca and the increase of the relative content of element Na. XRD results showed that Haliotidis Concha mainly contained CaCO3 of aragonite and calcite, while calcined Haliotidis Concha only contained CaCO3 of calcite, and standard decoction mainly contained CaCO3 of calcite and Na2CO3 of natrite. FTIR results showed that there were internal vibrations of O-H, C-H, C=O, HCO3- and CO32- groups in Haliotidis Concha, while O-H, HCO3- and CO32- groups existed in the calcined products and standard decoction. ConclusionThe changes of Haliotidis Concha and calcined Haliotidis Concha are mainly the increase of CaCO3 content, the transformation of CaCO3 aragonite crystal form to calcite crystal form and the absence of organic components after calcination, and the changes of calcined products and standard decoction are mainly the decrease of CaCO3 content and the increase of Na2CO3 relative content. The method established in the study is applicable to the quality control of the shellfish medicines-decoction pieces- standard decoction, which provides a new idea for the study of quality control of dispensing granules of shellfish medicines.
7.Predictive value of peripheral blood SNORD55 for prognosis of atrial fibrillation patients
Yu WANG ; Na WU ; Lanqing YANG ; Zhiquan YUAN ; Chengying LI ; Long WU ; Yuhong ZENG ; Lei YANG ; Yanxiu CHEN ; Xinghua CHEN ; Li ZHONG ; Jingyuan YANG ; Yafei LI
Journal of Army Medical University 2025;47(2):151-160
Objective To explore the association between the relative expression level of SNORD55 in peripheral blood and the outcomes of all-cause mortality and stroke in patients with atrial fibrillation(AF),and to evaluate the predictive value of SNORD55 for prognosis.Methods A total of 133 patients with non-valvular AF admitted in Department of Cardiology of the First Affiliated Hospital of Army Medical University from January 2014 to December 2017 were enrolled in this study.Their baseline information was collected,and the relative expression level of plasma SNORD55 was detected.Cox proportional hazards model was used to explore the association between the relative expression level of SNORD55 in peripheral blood and all-cause mortality as well as stroke in the patients.The predictive performance of CHA2DS2-VASc score for all-cause mortality and stroke was compared with the score combined with the relative expression level of SNORD55 in the AF patients.The area under the receiver operating characteristic curve(AUC)was utilized to evaluate the discrimination,and the net reclassification index(NRI)and comprehensive discriminant improvement index(IDI)were calculated to evaluate the improvement of reclassification ability.Decision curve analysis(DCA)was applied to analyze the change in clinical net benefit.Results The results of multivariate Cox regression showed that high expression of SNORD55 in peripheral blood was an independent risk factor for all-cause mortality and stroke in the AF patients.In predicting the outcomes of all-cause mortality and stroke,the addition of relative expression SNORD55 level with the CHA2DS2-VASc score obtained higher AUC value[0.80(95%CI:0.67~0.93)vs 0.67(95%CI:0.53~0.81),P<0.05].In predicting the outcome of all-cause death and stroke,combination of the relative expression level of SNORD55 with CHA2DS2-VASc score increased both NRI[54.3(95%CI:10.6~61.9)vs 31.9(95%CI:2.8~47.5),P<0.05]and IDI[16.1(95%CI:2.4~27.0)vs 7.9(95%CI:0.5~14.8),P<0.05].The results of DCA showed that our combination of CHA2DS2-VASc score relative expression level of SNORD55 had higher clinical net benefits than the foreign ABC score in the prediction of the outcomes.Conclusion Peripheral blood SNORD55 level is an independent risk factor for all-cause mortality and stroke in AF patients,and has good predictive performance for all-cause mortality and stroke in the patients.
8.Therapeutic efficacy and mechanism of artesunate for mouse model of polycystic ovary syndrome
Xueling WANG ; Peiling ZHONG ; Zhipeng ZHAO ; Fei CHEN ; Xin LIU ; Sijia LIU ; Lie YUAN ; Lu FANG ; Qianyi YAO ; Xiong YANG ; Chao LIU ; Jiakun CHENG ; Yongqing CAI ; Xiaoli LI ; Weihong LI
Journal of Army Medical University 2025;47(3):193-204
Objective To investigate the therapeutic efficacy of artesunate(AS)on polycystic ovary syndrome(PCOS)in mice and explore the potential mechanism primarily.Methods Twenty-five female C57BL/6J mice were randomly divided into Control group,model group(PCOS group),low-and high-dose AS groups(AS15 and AS30 groups)and metformin group(Met group).In addition to the Control group,the mouse model of PCOS was established by subcutaneous injection of dehydroepiandrosterone(DHEA,60 mg/kg)following by a high-fat diet for 21 d.After modeling,AS of 15 and 30 mg/kg was intraperitoneally injected into the mice of the AS 15 and AS30 groups,respectively,and 200 mg/kg Met was given to those of the Met group by gavage,once per day,for 6 weeks.ELISA was used to detect serum testosterone(T),fasting insulin(FINS),luteinizing hormone(LH)and follicle-stimulating hormone(FSH),and the LH/FSH ratio was calculated.The levels of fasting blood glucose(FBG),triglyceride(TG)and total cholesterol(TC)were detected by automatic biochemical analyzer,and the homeostasis model assessment of insulin resistance(HOMA-IR)was calculated.The estrous cycle was observed,and HE staining was performed for pathological changes in the ovary and uterus.Immunofluorescence assay was employed to measure the expression of p-eIF2α,ATF4 and CHOP in the ovarian tissue.After steroidogenic human granulosa-like tumor cell line KGN were exposed to 100 μmol/L DHEA to simulate the hyperandrogen environment of PCOS,and then treated with 5 and 10 μg/mL AS for 24 h,the protein levels of endoplasmic reticulum stress signaling pathway was detected by Western blotting.Results Compared with the Control group,the PCOS mice had disturbed estrous cycle,polycystic changes in the ovaries,and significantly increased serum T level and LH/FSH ratio(P<0.05),and obviously elevated HOMA-IR,TC and TG levels in terms of metabolism(P<0.01).The expression levels of p-eIF2α,ATF4 and CHOP were notably up-regulated in the ovarian granulosa cells of PCOS mice and KGN cells after DHEA exposure(P<0.05).Additionally,AS treatment attenuated the pathological changes of ovary and uterine expression,decreased the serum T level and the LH/FSH ratio(P<0.05),and reduced HOMA-IR,TC and TG levels(P<0.05)when compared with the PCOS mice.Moreover,the expression levels of p-eIF2α,ATF4 and CHOP were significantly down-regulated after AS treatment in both ovarian granulosa cells of PCOS mice and KGN cells(P<0.05).Conclusion AS significantly improves glycolipid metabolic disorder and reproductive dysfunction in PCOS mice,which may be associated with its suppressing endoplasmic reticulum stress by inhibiting the PERK/eIF2α/ATF4/CHOP pathway.
9.Predictive value of peripheral blood piR-hsa-2700592 for prognosis of atrial fibrillation patients
Lei YANG ; Na WU ; Lanqing YANG ; Yanxiu CHEN ; Xinghua CHEN ; Zhiquan YUAN ; Chengying LI ; Long WU ; Yuhong ZENG ; Yu WANG ; Li ZHONG ; Jingyuan YANG ; Yafei LI
Journal of Army Medical University 2025;47(6):551-560
Objectives To explore the association of peripheral blood PIWI-interacting RNA,piR-hsa-2700592,with all-cause mortality and stroke outcomes in patients with atrial fibrillation(AF),and to determine whether piR-hsa-2700592 has the potential to be an AF biomarker.Methods A total of 127 patients with non-valvular AF were enrolled,and the relative expression level of plasma piR-hsa-2700592 was detected.Cox proportional hazard regression was used to analyze the correlation between the expression of piR-hsa-2700592 and all-cause death as well as stroke outcome in the patients.Then the molecule expression level was combined with CHA2DS2-VASc score and ABC stroke(or death)score to establish 2 new prediction models,the improvement of the predictive performance was compared and analyzed.Receiver operating characteristic(ROC)curve analysis(area under the curve,AUC),net reclassification index(NRI),and comprehensive discriminant improvement index(IDI)were used to evaluate the predictive performance,and decision curve analysis(DCA)was employed to assess the clinical benefit.Results Multivariate Cox regression analysis showed that the patients with higher expression level of piR-hsa-2700592 in peripheral blood had a higher risk of stroke(HR:2.203,95%CI:1.120~4.332;P=0.022).In the stroke outcome,combination of plasma piR-hsa-2700592 expression level with CHA2DS2-VASc score and ABC stroke score obtained an AUC of 0.70(95%CI:0.55~0.85,P<0.001)and 0.84(95%CI:0.73~0.96,P=0.02),respectively.But,no significant association was observed between high plasma piR-hsa-2700592 level and all-cause mortality in the AF patients(HR:1.997;95%CI:0.884~4.509;P=0.096).Combination of plasma piR-hsa-2700592 level improved the discriminative capability than the single CHA2DS2-VASc score and ABC stroke score models,with an NRI and IDI value of 44.20%(95%CI:3.40~59.90,P<0.001)and 8.20%(95%CI:0.60~15.40,P<0.001),respectively for the new CHA2DS2-VASc score model,and an NRI and IDI value of 44.20%(95%CI:9.80~58.90,P<0.001)and 10.40%(95%CI:0.70~21.40,P<0.001),respectively for the new ABC stroke score model.The DCA curve showed that both new prediction models obtained better net clinical benefits.Conclusion High peripheral blood expression of piR-hsa-2700592 is an independent risk factor for stroke in the AF patients,and the indicator has a good predictive value for prognosis of the patients.piR-hsa-2700592 might be used as a potential biomarker in the diagnosis and prevention of cardiovascular diseases.
10.An Electronic Microbial Growth Analyzer-based Method for Rapidly Screening Viable Salmonella in Food
Ruo-Han LIANG ; Xiao-Dan PU ; Feng LU ; Xue-Ting ZHU ; Yuan-Yuan ZHANG ; Xiao-Yang WANG ; Qian-Qian YANG ; Hao LI ; Xu-Zhi ZHANG ; Chen-Zhong LI ; Shan LIU
Chinese Journal of Analytical Chemistry 2025;53(10):1694-1704
Foodborne illnesses caused by Salmonella pose significant threats to worldwide public health safety.In this study,a rapid method for screening viable Salmonella in oyster sauce and milk was developed by utilizing an electronic microbial growth analyzer(EMGA).Target food samples were diluted 10-fold with RVS broth and loaded into test tubes.Test tubes were positioned in the EMGA to determine the bacterial growth curves and the time required to reach the maximum growth rate(Tmgr).Using Salmonella typhimurium(S.typhimurium)asan model species,there was linear relationship between the logarithmic value of viable bacterial concentration(lgC)and Tmgr over the range of 5×101-5×106 CFU/mL,with a detection limit of 10 CFU/mL.For oyster sauce,the regression equation was Tmgr(min)=-80.775lg[C/(CFU/mL)]+754.96(R2=0.9907),and the recovery rates of S.typhimurium ranged from 95.2%to 119.8%,with relative standard deviations(RSD)ranging from 3.5%to 16.3%.For milk,the regression equation was Tmgr(min)=-71.922 lg[C/(CFU/mL)]+618.65(R2=0.9985),with recovery rates ranging from 98.4%to 110.6%and RSD ranging from 6.4%to 12.8%.The EMGA method required only one portable instrument,and involving only three manual steps,i.e.,dilution,transfer,and insertion.When S.typhimurium contamination reached 106 CFU/mL,the total time consumption,from the unwrapping of samples to the readout of bacterial concentration,was no more than 7 h.When applied to detection of actual oyster sauce and milk samples,the new method demonstrated strong consistency with plate counting results in positive detection rates.This method was superior to the plate counting method,which was generally considered as a gold standard,in terms of accuracy,precision,simplicity and efficiency,representing a promising alternative for the on-site screening and quantification of viable Salmonella in oyster sauce and milk products.

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