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Background: A significant portion of South Korea's population, approximately a quarter, owns pets, with dogs being the most popular choice among them. However, studies analyzing the fecal organism communities of dogs in South Korea are lacking, and limited efforts have been exerted to identify pathogens with potential zoonotic implications. Therefore, this study aimed to investigate potential pathogens using metabarcoding analysis and evaluate the risk of zoonotic diseases in dog feces in Seoul, South Korea. Methodology: Fecal samples were collected from both pet and stray dogs in the Mapo district of Seoul. Next-generation sequencing (NGS) was utilized, employing 16S rRNA amplicon sequencing to identify prokaryotic pathogens, and 18S rRNA amplicon sequencing for eukaryotic pathogens. The data obtained from the QIIME2 pipeline were subjected to various statistical analyses to identify different putative pathogens and their compositions. Principal findings: Significant variations in microbiota composition were found between stray and pet dogs, and putative prokaryotic and eukaryotic pathogens were identified. The most prevalent putative bacterial pathogens were Fusobacterium, Helicobacter, and Campylobacter. The most prevalent putative eukaryotic pathogens were Giardia, Pentatrichomonas, and Cystoisospora. Interestingly, Campylobacter, Giardia, and Pentatrichomonas were found to be significantly more prevalent in stray dogs than in pet dogs. The variation in the prevalence of potential pathogens in dog feces could be attributed to environmental factors, including dietary variances and interactions with wildlife, particularly in stray dogs. These factors likely contributed to the observed differences in pathogen occurrence between stray and pet dogs. Conclusions/Significance: This study offers valuable insights into the zoonotic risks associated with dog populations residing in diverse environments. By identifying and characterizing putative pathogens in dog feces, this research provides essential information on the impact of habitat on dog-associated pathogens, highlighting the importance of public health planning and zoonotic risk management. Author summary: The ownership of pets, especially dogs, is widespread in South Korea, with millions of people choosing them as companions. However, there is a lack of research on the composition of organisms from dog feces and the identification of potential disease-causing pathogens that can affect both dogs and humans. Understanding these risks is crucial as many infectious diseases can be transmitted from animals to humans. In this study, we used metabarcoding techniques to analyze the fecal organisms of pet and stray dogs in Seoul, South Korea. We found significant differences in the microbiota composition between stray and pet dogs, and we identified putative bacterial pathogens, such as Helicobacter, Campylobacter, and Fusobacterium, and eukaryotic pathogens, such as Giardia, Pentatrichomonas, and Cystoisospora. The prevalence of these putative pathogens was higher in stray dogs compared to pet dogs. These findings emphasize the importance of public health planning and zoonotic disease control, particularly in densely populated urban areas where the risk of zoonotic pathogens associated with dogs is amplified. It is crucial to educate pet owners and the general public about the potential risks associated with exposure to dog feces and contaminated environments. [ABSTRACT FROM AUTHOR]

The gut microbiome plays an essential role in host immune responses, including allergic reactions. However, commensal gut microbiota is extremely sensitive to antibiotics and excessive usage can cause microbial dysbiosis. Herein, we investigated how changes in the gut microbiome induced by ampicillin affected the production of IgG1 and IgG2a antibodies in mice subsequently exposed to Anisakis pegreffii antigens. Ampicillin treatment caused a notable change in the gut microbiome as shown by changes in both alpha and beta diversity indexes. In a 1-dimensional immunoblot using Anisakis-specific anti-mouse IgG1, a 56-kDa band corresponding to an unnamed Anisakis protein was detected using mass spectrometry analysis only in ampicillin-treated mice. In the Anisakis-specific anti-mouse IgG2a-probed immunoblot, a 70-kDa band corresponding to heat shock protein 70 (HSP70) was only detected in ampicillin-treated and Anisakis-immunized mice. A 2-dimensional immunoblot against Anisakis extract with immunized mouse sera demonstrated altered spot patterns in both groups. Our results showed that ampicillin treatment altered the gut microbiome composition in mice, changing the immunization response to antigens from A. pegreffii. This research could serve as a basis for developing vaccines or allergy immunotherapies against parasitic infections. [ABSTRACT FROM AUTHOR]

This article proposes the method for conducting thermal vibration analyses of the composite sandwich plate of a satellite in the space environment. Based on the continuous model, the method is derived using the Rayleigh-Ritz method and includes thermo-elastic coupling vibration by the space environment. In addition, the validity of the method is verified by the results of the finite element analysis and experimental analysis. Finally, parametric analysis is performed to investigate thermo-elastic coupling vibration characteristics of a satellite structure. This result allows a database to be design guidelines of composite sandwich structures for aerospace applications. We then concluded that the method is well-suited to thermally induced vibration analysis of a composite sandwich plate for aerospace applications due to their relative simplicity and computational efficiency. [ABSTRACT FROM AUTHOR]

The objective of this study was to perform fault diagnosis (FD) specific to various faults that can occur in the thrusters of remotely operated vehicles (ROVs) during hovering control. Underwater thrusters are predominantly utilized as propulsion systems in the majority of ROVs and are essential components for implementing motions such as trajectory tracking and hovering. Faults in the underwater thrusters can limit the operational capabilities of ROVs, leading to permanent damage. Therefore, this study focused on the FD for faults frequently caused by external factors such as entanglement with floating debris and propeller breakage. For diagnosing faults, a data-based technique that identifies patterns according to data characteristics was utilized. In imitation of the fault situations, data for normal, breakage and entangled conditions were acquired, and Density-Based Spatial Clustering of Applications with Noise (DBSCAN) was employed to differentiate between these fault conditions. The proposed methodology was validated by configuring an ROV and conducting experiments in an engineering water tank to verify the performance of the FD. [ABSTRACT FROM AUTHOR]

Background: Atopic dermatitis (AD) is a complex condition characterized by impaired epithelial barriers and dysregulated immune cells. In this study, we demonstrated Forsythia velutina Nakai extract (FVE) simultaneously inhibits basophils, macrophages, keratinocytes, and T cells that are closely interrelated in AD development. Methods: We analyzed the effect of FVE on nitric oxide and reactive oxygen species (ROS) production in macrophages, basophil degranulation, T cell activation, and tight junctions in damaged keratinocytes. Expression of cell‐type‐specific inflammatory mediators was analyzed, and the underlying signaling pathways for anti‐inflammatory effects of FVE were investigated. The anti‐inflammatory effects of FVE were validated using a DNCB‐induced mouse model of AD. Anti‐inflammatory activity of compounds isolated from FVE was validated in each immune cell type. Results: FVE downregulated the expression of inflammatory mediators and ROS production in macrophages through TLR4 and NRF2 pathways modulation. It significantly reduced basophil degranulation and expression of type 2 (T2) and pro‐inflammatory cytokines by perturbing FcεRI signaling. Forsythia velutina Nakai extract also robustly inhibited the expression of T2 cytokines in activated T cells. Furthermore, FVE upregulated the expression of tight junction molecules in damaged keratinocytes and downregulated leukocyte attractants, as well as IL‐33, an inducer of T2 inflammation. In the AD mouse model, FVE showed superior improvement in inflammatory cell infiltration and skin structure integrity compared to dexamethasone. Dimatairesinol, a lignan dimer, was identified as the most potent anti‐inflammatory FVE compound. Conclusion: Forsythia velutina Nakai extract and its constituent compounds demonstrate promising efficacy as a therapeutic option for prolonged AD treatment by independently inhibiting various cell types associated with AD and disrupting the deleterious link between them. [ABSTRACT FROM AUTHOR]