Objective:To characterize the antimicrobial resistance, resistance machanism and population genetics of Salmonella( S.) Derby in China, preliminarily reveal the population genetic characteristics of S. Derby in China, discover possible transmission patterns or potential transmission pathways, and provide certain reference for strengthening S. disease monitoring and developing prevention and control strategies. Methods:A total of 201 strains of S. Derby from different areas in China were used for the susceptible tests to 16 antibiotics and whole-genome sequencing. Finally, combined with the genome sequences of 134 strains of S. Derby from public databases, 335 strains of S. Derby were used for resistance genotype analysis and multi-locus sequence typing (MLST), and a phylogenetic tree based on the core genome single nucleotide polymorphisms was constructed for evolutionary analysis. Results:The results showed that 201 strains of S. Derby showed resistance to 16 kinds of antibiotics at different levels. The overall resistance rate was 97.51%. The resistance rates to antibiotics varied in S. Derby from different sources (human, animal, and food), the differences were significant (all P<0.05). A total of 38 resistance genes were carried by 335 strains of S. Derby, of which, fosfomycin gene fosA7 was found in all the strains (100.00%) and aminoglycoside genes aac(6')-Iaa accounted for 99.70%. The consistency of resistance genes and phenotypes varied with antibiotics. Except aminoglycosides and chloramphenicol, the consistencies of resistance genes and phenotypes for other antibiotics were high. MLST showed that 334 strains of S. Derby belonged to ST40. Phylogenetic trees indicated the risk for cross-infection between animal and human, food and human, and the possibility of long-distance interprovincial transmission of the bacteria by animal, to which further epidemiological studies are needed. Conclusions:The drug resistance of S. Derby is serious in China and the risk for cross-transmission between human and animal or food exists. It is necessary to establish and strengthen the comprehensive surveillance and risk assessment to prevent the spread of antibiotic resistant strains or elements through animal, food and human chains.

Objective:To establish a matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) assay for the identification of common Salmonella serotypes and provide etiology evidence for the early precise treatment of salmonellosis. Methods:A total of 500 strains were collected from different regions and sources and five predominant Salmonella serotypes ( Salmonella Typhi , Salmonella Paratyphi A , Salmonella Typhimurium , Salmonella Enteritidis , and Salmonella Indiana) of each strain was identified by agglutination test and whole-genome sequencing. The protein complex of the strains was extracted by using optimized pretreatment method to establish the fingerprint database of peptides for each Salmonella serotype. The new serotyping assays were established by using different modules based on the mass spectra database. Additional 155 strains with specified serotypes and variant sources were used to test and evaluate the accuracy of the new typing assays. Results:Five MALDI-TOF MS databases were established, and two new serotyping assays were established via peptide fingerprint mapping/matching and machine learning of the neuronal convolutional network respectively based on the databases. The results showed that the fingerprint matching approach could quickly identify five common Salmonella serotypes in clinical practice compared with the machine learning method, the accuracy of fingerprint matching assay to identify five Salmonella serotypes reached 100.00% and the serotyping can be conducted within a short time (15-20 minutes) and had a good reproducibility, while the machine learning method could not completely identify these serotypes. Moreover the sensitivity and specificity of fingerprint matching assay were all 100.00% respectively, while they were only 82.23% and 95.81% for machine learning method. Conclusion:The established Salmonella serotyping assay based on MALDI-TOF MS in this study can easily, rapidly and accurately identify different serotypes of Salmonella.

Objective:To analyze the endoscopic characteristics of early gastric cancer and precancerous lesions after Helicobacter pylori ( H. pylori) eradication. Methods:From May 2019 to June 2022, at Shanghai Sixth People′s Hospital affiliated to Shanghai Jiaotong University School of Medicine, the medical data of patients diagnosed with differentiated early gastric cancer and precancerous lesions were collected. A total of 93 patients with early gastric cancer and precancerous lesions who had previous history of H. pylori infection and had undergone standardized eradication treatment were selected, and their endoscopic characteristics were retrospectively analyzed. Independent sample t-test, chi-square test, and Fisher′s exact test were used for statistical analysis. Results:Among 93 patients with early gastric cancer and precancerous lesions after H. pylori eradication, there were 56 males and 37 females, with an average age of (66.9±8.2) years old. The time after H. pylori eradication was 3.4 years (range 1.0 to 7.0 years). A total of 109 early gastric cancer and precancerous lesions were found, including 79 patients with single lesion and 14 patients with multiple lesions (30 lesions). There were 60 cases with 73 lesions in the early gastric cancer group and 33 cases with 36 lesions in the precancerous group. Among 93 patients, 89 cases (95.7%) were diagnosed with atrophy level above C-2 according to Kimura-Takemoto classification under endoscopy. The long diameter of 109 lesions was (1.38±0.70) cm and the short diameter was (1.04±0.53) cm. A total of 80 lesions (73.4%) were located in the lower 1/3 part of the stomach, and 53 lesions (48.6%) were located in the lesser curvature. A total of 106 lesions (97.2%) were superficial type (0-Ⅱ) under the endoscopy. The long diameter and short diameter in the early gastric cancer group after H. pylori eradication were both greater than those in the precancerous lesion group ((1.54±0.78) cm vs. (1.06±0.35) cm, (1.16±0.58) cm vs. (0.78±0.33) cm), and the differences were statistically significant ( t=3.53 and 3.73, both P<0.001). There was statistically significant difference in the morphological types between early gastric cancer group after H. pylori eradication and precancerous lesion group ( χ2=11.01, P=0.012). The main morphological type of early gastric cancer after H. pylori eradication was superficial depression type (0-Ⅱc), accounting for 45.2% (33/73), while the precancerous lesions were mainly superficial protruded and flat type, both accounting for 38.9% (14/36). Conclusions:After H. pylori eradication, the endoscopic atrophy range of early gastric cancer and precancerous lesions is mostly above C-2. And the lesions are mostly located in the middle and lower 1/3 part of the stomach, long diameter of lesions <20 mm. The main morphological type is superficial type, especially superficial depression type.

This study was performed to explore the impact of glutamine(Gln)on the anti-tumor immune response of CD8+ T cells and its mechanism.TCGA database was used to analysis the relationship between tumor Gln metabolism and the quantity and functionality of infiltrating CD8+ T cells.CRISPR/Cas9 was employed to knock down GLS expression in mouse MC38 cells,and a mouse tumor model was established.Flow cytometry was conducted to assess tumor proliferation,apoptosis,and the quantity and functionality of tumor-infiltrating immune cells.Lymphocytes isolated from health individuals were treated with Gln-deficient media,complete media or media supplemented with GSH,RSL3 in vitro.Then the apoptosis,the expression levels of GPX4,Lipid-ROS,and effector function protein of CD8+ T cells were detected by flow cytometry.Furthermore,RNA-seq was performed to analyze the differential gene expression on the Gln-depleted CD8+ T cells.Data showed that tumor Gln metabolism was inversely associated with the quantity and functionality of tumor-infiltrating CD8+ T cells.Low expression of GLS in MC38 cells could inhibit C57BL/6 tumor growth,decrease Ki-67 expression,promote casepase-3 expression,increase the amount of tumor-infiltrating immune cells,suppress PD-1,TIM-3,and LAG-3 expression,and enhance CD137,CD107a,IFN-γ and TNF-α expression in tumor-infiltrating CD8+ T cells.RNA-seq results indicated an upregulation of ferroptosis genes TFRC,HMOX1,CYBB and SLC7A11 in CD8+ T cells following glutamine deficiency.Gln deficiency led to lower CD137,CD107a,IFN-γ,GSH,GPX4 expression,increased Lipid-ROS level,and caused cell death in CD8+ T cells.Supplementation of GSH upregulated GPX4 expression,downregulated Lipid-ROS level,and increased IFN-γ secretion in CD8+ T cells.In conclusion,Gln deficiency inhibits the effector function of CD8+ T cells by inducing ferroptosis,and promotes tumor growth.

Objective: To establish a rapid detection method for Salmonella based on the combination of enzymatic recombinase amplification (ERA) and lateral flow chromatography (LF), so as to provide technical support for the on-site detection of Salmonella. Methods: Specific ERA primers and probes were designed based on the highly conserved flagella gene fimY in Salmonella. The primers were screened using capillary electrophoresis, and the probes were designed according to the amplification range of the screened primers. The amplification temperature and time were optimized to establish the amplification method, and the product was detected using LF strips. A standard strain of Salmonella was used to verify the sensitivity, 10 other gut bacteria were used to to verify the specificity and sensitivity, and the nucleic acid of the actual Salmonella strains was amplified to verify the detectability. Results: After screening for Salmonella-specific primers using capillary electrophoresis, the minimum detection concentration was 5 copies/μL under the amplification temperature of 37 ℃ and reaction time of 20 minutes. This method had a positive amplification result for Salmonella nucleic acid, and the amplification results of 10 other gut bacteria were all negative, with good specificity. Conclusion This method provides a possibility for on-site point of care testing of Salmonella infection.

Salmonellosis is one of the common food-borne diseases, local and cross-region outbreaks are not rare. The risk of cross-border transmission of Salmonella is increasing with the high frequency of global economic trades. The recently occurred multi-country outbreaks of Salmonella Typhimurium infection associated with chocolate products have highlighted the importance of improving capability of surveillance and warning of foodborne-disease, especially salmonellosis, in China. It is essential to strengthen the collaboration among clinical medicine, disease control and food safety institutions, improve the capability of whole-genome sequencing of Salmonella for the disease surveillance and tracing, and facilitate the information sharing and collaboration among the food safety related sectors for the timely detection, prevention and control of outbreaks of Salmonella infection in China.

The first branchial arch (BA1), which is derived from cranial neural crest (CNC) cells, gives rise to various orofacial tissues. Cre mice are widely used for the determination of CNC and exploration of gene functions in orofacial development. However, there is a lack of Cre mice specifically marked BA1's cells. Pax2-Cre allele was previously generated and has been widely used in the field of inner ear development. Here, by compounding Pax2-Cre and R26R-mTmG mice, we found a specific expression pattern of Pax2
Animals ; Bone Morphogenetic Protein 4 ; Branchial Region ; Mesenchymal Stem Cells ; Mice ; Skull

Objective:To analysis the incidence of abnormal genetics and the clinical outcome of fetuses with ultrasonic nonstructural abnormality.Methods:This study was conducted retrospectively. 631 pregnant women were enrolled in the Prenatal Diagnostic Center of Fujian Maternal and Child Health Hospital due to ultrasonic nonstructural abnormality from January 2016 to January 2019. According to different gestational weeks, amniotic fluid or umbilical cord blood samples were collected for chromosome karyotype analysis and SNP-array. According to the number of nostructural abnormalities, they were divided into 1 nostructural abnormality group, 2 nostructural abnormalities group, and ≥3 nostructural abnormalities group. Chi-square test was used for comparison between groups.Results:Of the 631 cases, 34 cases (5.4%, 34/631) had abnormal karyotypes, including 20 cases with abnormal chromosome number and 14 cases with abnormal chromosome structure. In results of SNP-array, there were 53 abnormal results (8.4%, 53/631), including 32 cases of pathogenic copy number variations (CNV) and 21 cases of variations of uncertain clinical significance (VOUS). The rates of pathogenic CNV were 4.57% (21/260), 4.76% (7/147) and 16.67% (4/24) in the group of 1, 2 and ≥3 nostructural abnormalities, respectively. The rate of the three groups showed a linear trend, and the difference was statistically significant (χ2=7.419, P<0.05). In the single nostructural abnormality group, the rate of pathogenic CNV of nasal bone dysplasia, fetal growth restriction (FGR) and thickened nuchal translucency (NT) were 8.11% (3/37), 7.04% (5/71) and 5.60% (7/125), respectively. Conclusions:Compared with the karyotype analysis, SNP-array can significantly improve the detection rate of genetic abnormalities in ultrasonic nonstructural abnormality. When multiple ultrasonic nonstructural abnormality were combined, the risk of genetic abnormalities showed an upward trend.

Objective:To analysis the incidence of abnormal genetics and the clinical outcome of fetuses with ultrasonic nonstructural abnormality.Methods:This study was conducted retrospectively. 631 pregnant women were enrolled in the Prenatal Diagnostic Center of Fujian Maternal and Child Health Hospital due to ultrasonic nonstructural abnormality from January 2016 to January 2019. According to different gestational weeks, amniotic fluid or umbilical cord blood samples were collected for chromosome karyotype analysis and SNP-array. According to the number of nostructural abnormalities, they were divided into 1 nostructural abnormality group, 2 nostructural abnormalities group, and ≥3 nostructural abnormalities group. Chi-square test was used for comparison between groups.Results:Of the 631 cases, 34 cases (5.4%, 34/631) had abnormal karyotypes, including 20 cases with abnormal chromosome number and 14 cases with abnormal chromosome structure. In results of SNP-array, there were 53 abnormal results (8.4%, 53/631), including 32 cases of pathogenic copy number variations (CNV) and 21 cases of variations of uncertain clinical significance (VOUS). The rates of pathogenic CNV were 4.57% (21/260), 4.76% (7/147) and 16.67% (4/24) in the group of 1, 2 and ≥3 nostructural abnormalities, respectively. The rate of the three groups showed a linear trend, and the difference was statistically significant (χ2=7.419, P<0.05). In the single nostructural abnormality group, the rate of pathogenic CNV of nasal bone dysplasia, fetal growth restriction (FGR) and thickened nuchal translucency (NT) were 8.11% (3/37), 7.04% (5/71) and 5.60% (7/125), respectively. Conclusions:Compared with the karyotype analysis, SNP-array can significantly improve the detection rate of genetic abnormalities in ultrasonic nonstructural abnormality. When multiple ultrasonic nonstructural abnormality were combined, the risk of genetic abnormalities showed an upward trend.

Objective To analyze the expression of peripheral blood CD13+CD4+CD25hi regulatory T cells (Treg cells) in patients with diffuse large B-cell lymphoma (DLBCL) and its clinical significance. Methods The expression of peripheral blood CD13+CD4+CD25hi Treg cells in 58 newly diagnosed patients with DLBCL and 30 healthy adults was detected by flow cytometry, and the relationship between its expression and the clinical indicators were analyzed statistically. Results The levels of peripheral blood CD13+CD4+CD25hi Treg cells in newly diagnosed DLBCL and healthy adults were different, with statistically significant difference [(36.37 ±11.89) % vs. (9.03 ±2.10) %, t = 7.168, P < 0.001]. The level of peripheral blood CD13+CD4+CD25hi Treg cells was significantly higher in patients with IPI score 3ˉ5 than that in patients with IPI score 0ˉ2[(44.28±10.10)%vs. (21.51±6.23)%, t=ˉ9.347, P=0.03]. The expression of peripheral blood CD13+ CD4+ CD25hi Treg cells in stages Ⅱ, Ⅲ and Ⅳ patients were (19.48 ±1.34) %, (33.98 ±8.03) % and (47.89±8.25) %respectively, and there were significant differences among three groups (F= 38.363, P<0.001). The levels of peripheral blood CD13+CD4+CD25hi Treg cells had no relationship with age, sex or LDH level (all P>0.05). Conclusion The levels of peripheral blood CD13+CD4+CD25hi Treg cells are higher in DLBCL patients, which has a close relationship between the expression of CD13+CD4+CD25hi Treg cells and clinical stage and prognosis.