An innovative on-site real-time avian influenza virus(AIV)detection method was estab-lished by integratingrecombinase-aided amplification(RAA)with the clustered regularly inter-spaced short palindromic repeats(CRISPR)/CRISPR-associated protein(Cas)system.After analy-zing 120 sequences of the M gene of avian influenza viruses of different subtypes publicly available on NCBI,the RAA primers and crRNA were designed based on the identified highly conserved segment and used for RAA nucleic acid amplification.After the amplified products were transferred to a CRISPR/Cas13a detection system,the fluorescence values were monitored throughout the re-action process to indicate the results.The sensitivity and specificity of the RAA-CRISPR/Cas13a method were validated using gradient dilutions(106-100 copies/μL)of positive plasmids and sev-en other avian viruses.Fifty clinical samples were tested using this method and compared with the national standard fluorescence RT-PCR method.The results indicated that the detection limit for RAA-CRISPR/Cas13a method was 102 copies/μL,a two-fold improvement over the standard RAA.Specificity assay showed the established method only detected AIV with no cross-reactivity with other seven avian viruses.Compared to the national standard fluorescence RT-PCR method,this method exhibited 100％specificity,95.24％accuracy,and 98.00％consistency in detection of clinical samples.In conclusion,a universal and rapid RAA-CRISPR/Cas13a for detection of AIV was established with the capacity of achieving detection within 60 minutes at 37 ℃,which provides a rapid,sensitive,and specific on-site detection method for AIV.

Salmonella is an important foodborne pathogen and one of the main causes of diarrhea. Every year, about 550 million people suffer from diarrhea due to Salmonella infection, of which about 230 000 die. It has become a major global public safety issue. The application fields of Salmonella detection involve food safety, water quality monitoring, animal husbandry, public health monitoring, and medical diagnosis. The detection requirements mainly come from three aspects: pathogen identification, serotype identification, drug resistance and virulence identification. In recent years, the detection technology for Salmonella has made rapid progress, especially the emergence and development of emerging molecular detection technologies, providing new perspectives for Salmonella detection in different scenarios. However, due to the diversity of Salmonella serotypes and the complexity of detection scenarios, existing detection technologies still have some pain points (such as long detection time, cumbersome operation steps, low scene adaptability, etc.). This article will elaborate on the application of several emerging molecular detection technologies with distinct characteristics, such as CRISPR Cas technology, digital PCR technology, sequencing technology, and microfluidic technology, in Salmonella detection. It aims to provide a reference for the development and improvement of Salmonella detection technology and the establishment of infection warning and control systems.

Recombinase polymerase amplification technology, as a new type of nucleic acid constant temperature amplification detection technology, has shown enormous application potential and development prospects in recent years. Its unique advantages such as high sensitivity, high specificity, low dependence on instruments, and the ability to integrate multiple detection modes make it widely applicable in multiple fields, especially in grassroots and on-site real-time detection. This article reviews the development history, detection principles, research and application progress of recombinant enzyme polymerase amplification technology, and looks forward to its future development, in order to provide useful references for the research and clinical application of rapid pathogen detection methods based on recombinant enzyme polymerase amplification technology.

Salmonella is an important foodborne pathogen and one of the main causes of diarrhea. Every year, about 550 million people suffer from diarrhea due to Salmonella infection, of which about 230 000 die. It has become a major global public safety issue. The application fields of Salmonella detection involve food safety, water quality monitoring, animal husbandry, public health monitoring, and medical diagnosis. The detection requirements mainly come from three aspects: pathogen identification, serotype identification, drug resistance and virulence identification. In recent years, the detection technology for Salmonella has made rapid progress, especially the emergence and development of emerging molecular detection technologies, providing new perspectives for Salmonella detection in different scenarios. However, due to the diversity of Salmonella serotypes and the complexity of detection scenarios, existing detection technologies still have some pain points (such as long detection time, cumbersome operation steps, low scene adaptability, etc.). This article will elaborate on the application of several emerging molecular detection technologies with distinct characteristics, such as CRISPR Cas technology, digital PCR technology, sequencing technology, and microfluidic technology, in Salmonella detection. It aims to provide a reference for the development and improvement of Salmonella detection technology and the establishment of infection warning and control systems.

Listeria monocytogenes is recognized as a significant foodborne pathogen, capable of causing listeriosis in humans, which is a global public health concern. This pathogen is particularly dangerous for pregnant women, as it can lead to invasive listeriosis in fetuses and neonates, posing a significant threat to both maternal and fetal health. Therefore, establishing suitable in vitro and in vivo models for L. monocytogenes placenta infection, as well as analyzing and exploring the infection process and its pathogenic mechanism, are important approaches to prevent and control L. monocytogenes infection in mothers and infants. In this study, we reviewed the in vitro and in vivo placental models used for studying the infection of L. monocytogenes in maternal and infant, summarized and discussed the advantages and limitations of each model, and explored the potential of in vitro cell models and organoids for the study of L. monocytogenes infection. This paper aims to support the study of the infection pathway and pathogenesis of listeriosis and provide scientific references for the prevention and control of L. monocytogenes infection.
Female ; Humans ; Pregnancy ; Listeria monocytogenes ; Listeriosis/prevention & control* ; Placenta/pathology* ; Public Health ; Infant, Newborn

ObjectiveThe contamination of foodborne pathogens in ready-to-eat fruits and vegetables in Shanghai was analyzed to provide a scientific basis for food safety， risk assessment and related supervision. MethodsFrom June to September 2021， a total of 143 batches of12 kinds of ready-to-eat fruits and vegetables such as lettuce， chicory， and cherry tomatoes were collected from farmers’ markets， supermarkets， and e-commerce platforms. The total number of bacterial colonies， Salmonella， Listeria monocytogenes， Staphylococcus aureus， Cronobacter spp. and Shiga toxin-producing Escherichia coli in the samples were tested according to National Food Contamination and Harmfulness Risk Monitoring Manual. ResultsAmong the 143 batches， foodborne pathogens were detected in 68 batches， with a total detection rate of 47.55% （68/143）. A total of 79 strains of foodborne pathogens were detected. The detection rate of Staphylococcus aureus was the highest （32.87%， 47/143）， followed by Cronobacter spp. （20.98%， 30/143）， Salmonella （0.70%， 1/143）， Listeria monocytogenes （0.70%， 1/143）， Shiga toxin-producing Escherichia coli （0.00%）. Furthermore， the detection rate was higher in different ready-to-eat fruits and vegetables： chicory （17.33%）， cucumber （17.14%）， cherry tomatoes （16.00%）， and honeydew melon （15.38%）， respectively. Meanwhile， the contamination rate of pathogens in ready-to-eat fruits and vegetables from farmers’ markets， supermarkets， and e-commerce platforms was relatively high. ConclusionReady-to-eat fruits and vegetables in Shanghai are contaminated by foodborne pathogens. The prevention and control of the contamination of post-harvest fruits and vegetables should be strengthened to reduce the risk of foodborne disease outbreaks.

Aiming at the management efficiency problems in the traditional medical low-value consumables management mode of the nursing unit, based on the perspective of supply chain management, this study uses lean management method to construct the lean management mode of low-value consumables with a whole cycle and whole process information monitoring, and analyzes the application effect of this mode. The results show that after the application of lean management mode, the low-value consumables of the nursing unit can achieve "consumables in use=priced consumables + un-priced consumables", the settlement cost is significantly reduced and its stability is high, and the efficiency of "supply-inventor-distribution" link is significantly enhanced. This model effectively improves the management efficiency of low-value consumables in the hospital, and also provides a reference for other hospitals to improve the management level of low-value consumables.
Hospitals ; Commerce

β-lactam antibiotics are a class of antibiotics widely used in clinical treatment. The antibacterial mechanism of them is to inhibit the cell wall synthesis of bacteria. However, the widespread of β-lactam resistance genes among bacteria has posed a great challenge to the use of β-lactam antibiotics. One of the main genes encoding β-lactamase is blaTEM, and 243 subtypes of it have been identified to date. Studying blaTEM gene is of great significance in antibiotic resistance research. This review focused on the discovery, structure, promoter, distribution, spread, antibacterial mechanism and research status of blaTEM gene, hoping to provide reference for further research on the subtypes of β-lactam resistance genes in bacteria.

Objective:To explore the association of DNA methylation with immune response to hepatitis B (HepB) vaccine in Han nationality children from Guangxi province.Methods:A total of 263 children aged 8-9 months who had completed HepB immunization program were recruited from three hospitals in Guangxi province by using unmatched case-control method. Children with the HepB surface antibody concentration(Anti -HBs)<100 mIU/ml was set as the case group and ≥100 mIU/ml as the control group. Multiplex PCR and heavy sulfite sequencing were used to treat the samples. Illumina platform was used for high-throughput DNA methylation sequencing of IFNG gene target regions and CpG sites. Unconditional logistic regression was used to analyze the association between cytosine-phospho-guanosine DNA methylation at 18 loci of IFNG gene and HepB immune response level. Results:There were 104 children in the case group and 159 in the control group. The median ( Q1, Q3) level of anti -HBs in two groups were 62.34 (30.06, 98.88) mIU/ml and 1 089.10 (710.35, 1 233.45) mIU/ml. The methylation levels of IFNG_1 gene 44 and 93 locus in the case group were higher than those in the control group ( P<0.05). The unconditional logistic regression model showed that the DNA methylation level of IFNG_1 gene at 44 ( OR=1.18, 95% CI: 1.03-1.35) and 93 ( OR=1.21, 95% CI: 1.07-1.38) locus was associated with the HepB response level. Conclusion:The changes of DNA methylation at locus 44 and 93 of IFNG_1 gene may be relevant factors affecting the response level of HepB in Han nationality children from Guangxi province.

Objective:To explore the association of DNA methylation with immune response to hepatitis B (HepB) vaccine in Han nationality children from Guangxi province.Methods:A total of 263 children aged 8-9 months who had completed HepB immunization program were recruited from three hospitals in Guangxi province by using unmatched case-control method. Children with the HepB surface antibody concentration(Anti -HBs)<100 mIU/ml was set as the case group and ≥100 mIU/ml as the control group. Multiplex PCR and heavy sulfite sequencing were used to treat the samples. Illumina platform was used for high-throughput DNA methylation sequencing of IFNG gene target regions and CpG sites. Unconditional logistic regression was used to analyze the association between cytosine-phospho-guanosine DNA methylation at 18 loci of IFNG gene and HepB immune response level. Results:There were 104 children in the case group and 159 in the control group. The median ( Q1, Q3) level of anti -HBs in two groups were 62.34 (30.06, 98.88) mIU/ml and 1 089.10 (710.35, 1 233.45) mIU/ml. The methylation levels of IFNG_1 gene 44 and 93 locus in the case group were higher than those in the control group ( P<0.05). The unconditional logistic regression model showed that the DNA methylation level of IFNG_1 gene at 44 ( OR=1.18, 95% CI: 1.03-1.35) and 93 ( OR=1.21, 95% CI: 1.07-1.38) locus was associated with the HepB response level. Conclusion:The changes of DNA methylation at locus 44 and 93 of IFNG_1 gene may be relevant factors affecting the response level of HepB in Han nationality children from Guangxi province.