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ObjectiveThis study aimed to analyze the serotype and phenotype of human and non-human sourced Salmonella from 1975 to 2021 in Fujian Province retrospectively.MethodsSalmonella isolates were collected from clinical hospitals， public service employee health， circulating fresh food， and the environment from 1975 to 2021 in Fujian Province， and serotypes and variants were distinguished using WHO-recommended Salmonella serotyping methods. Two prediction software were used based on whole genome sequencing， while the same antigen but different isolates or phenotypic variants were identified using biochemical combinations and MALDI-TOF-MS flight mass spectrometry.ResultsThere were 4 693 human- and non-human-sourced Salmonella isolates that contained 21 serogroups of four subspecies （18 from patients， 9 from healthy employees， 17 from food， and 8 from the environment）. Salmonella paratyphoid A， S. typhoid， S. enteritis， S. cholerae， S. typhimurium， S. rosen， and S. stanley were dominant isolates in the 30 total extraintestinal invasive serotypes. There were 96 Salmonella serotypes other than S. typhoid， S. paratyphoid A， and S. paratyphoid B （63 from patients， 51 from healthy employees， 60 from food， and 20 from the environment）， and the top 10 clinical serotypes were S. typhimurium， S. typhoid， S. enteritis， S. derby， S. stanley， S. paratyphoid A， S. anatum， S. wetavreden， S. rosen， and S. london， while the top 10 from food were S. anatum， S. derby， S. typhimurium， S. stanley， S. wetavreden， S. newport， S. enteritis， S. tompson， S. agona， and S. london. Fourteen serotypes （including 10 diphasic serotypes and 4 monophasic serotypes） had monophasic variants. Several serotypes had phenotypic variants such as hydrogen sulfide-negative， fermenter of lactose or sucrose， colony mucus type， and chromogenic type.ConclusionSalmonella are characterized by their biodiversity and multiple sources in Fujian Province. Invasive cases are gradually dominated by non-typhoid Salmonella. Laboratories should enhance their ability to diagnose monophasic variants and phenotypic variants of Salmonella， as well as pet and environmental traceability for scattered outbreaks of infectious diseases.

ObjectiveTo evaluate the equivalence of 5 Salmonella selective enrichment procedures in standard methods worldwide.MethodsThe growth rates（PR） and the colony characteristics of 5 selective enrichment broths（SC， TTB， RV， MKTTn， SBG） and 5 selective mediums（CAS， XLD， XLT4， HE， BS） were validated according to the GB4789.28—2013. The sensitivity（SE）， the relative trueness（RT） and the acceptable limit（AL） were estimated on highly contaminated foods through the use of 5 protocols combined with 5 selective enrichment broths and 2 selective mediums according to the method of ISO 16140—2：2016. The sensitivity（Se）， the specificity（Sp）， the positive predictive value（PPV） and the negative predictive value（NPV） were simultaneously determined through the use of 10 compound modes combined with selective enrichment broths and selective mediums according to the classical statistical methods.ResultsThe results showed that SC broth had no efficacy in enriching Salmonella enterica serotype Cholerae and Salmonella enterica serotype Cholerae var. Kunzendorf. The CAS and XLD were significantly better than XLT4， HE and BS in identifying typhoidal Salmonella and nontyphoidal Salmonella as well as the phenotype of hydrogen sulfide.Totally 84 samples（22 pieces of meat， 32 pieces of poultry and 30 pieces of aquatic products） were tested. 25 out of the 84（29.76%） were confirmed positive by 5 protocols， and 16 serotypes from 42 isolates were identified. The SE of 5 protocols were 84.00%， 100.00%， 88.00%，88.00% and 92.00%， respectively， but showed no statistically significant difference between each other. The AL of one protocol （SC+TTB） went beyond the limitation of the ISO 16140—2：2016 due to the ineffectiveness of SC broth. The compound mode of RV-CAS had the best comprehensive benefits， while the Se， the Sp， the PPV and the NPV of which were 68.00%， 95.00%， 85.00% and 88.00%， respectively.ConclusionThe ineffectiveness of SC broth reduces the sensitivity of the detection protocol for Salmonella， which could cause a negative deviation， resulting in the threshold exceeding of the Acceptability Limit （AL）. The combinational selective enrichment broth of RV-CAS is recommended to be the optimal mode， with CAS+XLD being recommended to be the optimal selective medium combination. The process of Salmonella serotyping is suggested to be improved in the standard of GB4789.4 to cope with the multi-serotype Salmonella contamination in food chain and be consistent with the international standardization for food microbiology.

Background The diagnosis of myasthenia gravis (MG) in children remains difficult. Circulating small extracellular vesicle (sEV)-derived miRNAs (sEV-miRNAs) have been recognized as biomarkers of various diseases and can be excreted by different cell types. These biomarker candidates also play a vital role in autoimmune diseases via intercellular communication. Methods In the present study, we used sEV isolation and purification methods to extract the plasma-derived sEV-miRNAs from children with MG and healthy controls. A small RNA sequencing analysis confirmed the miRNA expression features in plasma-derived sEVs from MG patients. The miRNA expression analysis in vitro was determined using microarray analysis. The enrichment and network analyses of altered sEV-miRNAs were performed using miRNA databases and Database for Annotation, Visualization, and Integrated Discovery website. Quantitative real-time polymerase chain reaction was performed for validation of sEV-miRNA. The diagnostic power of altered sEV-miRNAs was evaluated using receiver operating characteristic curve analyses. Results Twenty-four sEV-miRNAs with altered expression level were identified between groups by DESeq2 method. The miRNAs were extracted from the sEVs, which were isolated from human primary skeletal muscle cell culture treated with mAb198. The target genes and enriched pathways of sEV-miRNAs partially overlapped between cell supernatant and plasma samples. The significantly downregulated miR-143-3p was validated in quantitative real-time polymerase chain reaction analysis. Conclusions For the first time, we report that plasma-derived sEV-miRNAs may act as novel circulating biomarkers and therapeutic targets in pediatric MG. What is already known on this subject: The miRNA expression signature can potentially be used as a biomarker to diagnose a wide variety of diseases. Small extracellular vesicles (sEVs) can provide a stable environment for miRNA cargo to avoid degradation. What this study adds: Twenty-four sEV-miRNA candidates were differentially expressed in pediatric myasthenia gravis (MG) patients compared to healthy controls. Plasma-derived sEV-miR-143-3p has potential value in the diagnosis of pediatric autoantibody seronegative myasthenia gravis. How this study might affect research, practice, or policy: Our findings provide a set of plasma-derived sEV-miRNAs candidates for the diagnosis of pediatric myasthenia gravis, especially autoantibody seronegative patients. [ABSTRACT FROM AUTHOR]

ObjectiveTo investigate the genomic and virulence characteristics of seven invasive non-typhoidal Salmonella (iNTS) isolates.MethodsBased on the collection of seven iNTS strains, whole genome sequencing were performed. The serotypes, genomes and virulence factors were identified, annotated and analyzed according to the comparison of genome data and relevant databases.ResultsAmong the seven tested iNTS isolates, six were monophasic, including one Salmonella Typhimurium and two Salmonella I 4, [5], 12∶i∶-(ST34 type), two Salmonella Enteritidis, one Salmonella Corvallis and one unknown serotype with the antigenic formulae of I 4, [5], 12∶d∶- (ST279 type). No consistent rule was found in genomic components and relevant parameter differences varies much between different serotypes than those of the same serotype from different sources. The distribution of virulence factors (VF) was significantly different among different Salmonella serotypes, but the common VF characteristics in iNTS strains were not found, though Capsule/Immune evasion, toxin, peritrichous_flagella and Salmochelin may be associated with high invasiveness. All tested isolates contained type III and type VI secretion systems. The number of secretion protein, type III for S. Corvallis and type VI for Salmonella I 4, [5], 12∶d∶-was the highest among the seven isolates. Pseudogenization of the secreted effector SseI may exist among some Salmonella serotypes which may contribute to the enhancement of Salmonella invasiveness.ConclusionThe common characteristic differences of virulence factor between iNTS and gastroenteritis NTS were not observed at the moment, and highly invasive pathogenic mechanisms still require further analysis and research at the functional transcriptome and proteomic levels to determine the genetic basis of iNTS occurrence and transmission.

Kazakh is one of the multilingual languages of China and is widely spoken in some areas of Xinjiang, China. However, due to the fact that Kazakh is a language in which several characters are glued together to form a continuous word with a unique shape and complex structural combinations of relationships. This paper explores a solution for offline image retrieval of handwritten Kazakh words, which is a challenging task because, due to the lack of relevant datasets and the special writing morphology of the Kazakh language, traditional text image retrieval algorithms often struggle to achieve satisfactory results when dealing with writing styles that are varied and adherent to the language. Therefore, a dataset of offline Kazakh handwritten document images was created in this paper. The dataset contains 300 pages of document images with 20 500 words. Then, a new model called the 'AENet' is proposed. The model utilizes an attention mechanism to focus more finely on focal regions such as centers, inflection points, and contours of handwritten word images and to capture important local features from different scales. Fusion space pyramid pooling, feature aggregation, encoding operations, and feature downscaling and reconstruction are used to extract and reconstruct more representative feature representations from local to global to capture the overall information in the word images. Through experimental evaluation on Kazak‐80, Zilla‐64, and HWDB1.1‐375 datasets, it is verified that the method significantly improves the mAP for image retrieval of handwritten words, which is especially applicable to adhesive languages like Kazakh. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]