https://ir.ymlib.yonsei.ac.kr/handle/22282913/168790 Wed, 15 Jul 2026 16:25:40 GMT 2026-07-15T16:25:40Z https://ir.ymlib.yonsei.ac.kr/handle/22282913/213027 Title: Comparative Analysis of Gut Eukaryotic Communities in Three Laboratory-Reared Cockroach Species Using Metabarcoding Authors: Kang, Dongjun; Chavarria, Xavier; Choi, Jun Ho; Yi, Myung-hee; Jang, Yun Soo; Oh, Singeun; Choi, Du-Yeol; Shatta, Arwa; Yun, Sohyeon; Kim, Myungjun; Choe, Seongjun; Yong, Tai-Soon; Kim, Ju Yeong Abstract: Cockroaches are known reservoirs for diverse bacterial microbiomes. However, comprehensive analyses of the eukaryotic communities within cockroaches remain limited. In this study, we selected three long-term laboratory-reared cockroach species (Blattella germanica, Periplaneta fuliginosa, and Periplaneta japonica) and performed metabarcoding of the 18S rRNA V9 region using the iSeq 100 platform. The nematode Blatticola blattae was identified in B. germanica, and Leidynema appendiculata was found in both P. fuliginosa and P. japonica. The amplicon sequence variant (ASV) of Nyctotherus (Ciliophora) was detected in all three species of cockroach, while Entamoeba sp. was detected in P. fuliginosa and P. japonica. Compared with the other two species, B. germanica exhibited a higher prevalence of the fungus Nephridiophaga. Our findings showed that laboratory-reared cockroaches belonging to different species harbored distinct commensal and parasitic eukaryotic taxa. While most ASVs were of reduced clinical concern for humans as opposed to studies using wild-caught specimens, the detection of commensals, arthropod parasites and potential human pathogens illustrates the complexity of the cockroach-associated eukaryome and the influence of host identity. Our study emphasizes the importance of host-specificity in the eukaryotic community of laboratory-reared cockroach models. Fri, 01 May 2026 00:00:00 GMT https://ir.ymlib.yonsei.ac.kr/handle/22282913/213027 2026-05-01T00:00:00Z https://ir.ymlib.yonsei.ac.kr/handle/22282913/212771 Title: Nematode in Cockroaches: A Potential Allergen Source Authors: Kang, Dongjun; Yi, Myung-Hee; Choi, Jun Ho; Jang, Yun Soo; Choe, Seongjun; Kim, Ju Yeong Wed, 01 Apr 2026 00:00:00 GMT https://ir.ymlib.yonsei.ac.kr/handle/22282913/212771 2026-04-01T00:00:00Z https://ir.ymlib.yonsei.ac.kr/handle/22282913/211646 Title: Saccharomyces cerevisiae 48338 Suppresses Antibiotic-Induced Clostridioides difficile Infection in a Murine Model Authors: Kim, Eunjung; Kim, Hoyeon; Lee, Minjae; Kim, Beomjoong; Kim, Bobae; Kim, Haeun; Kim, Dongyeol; Kang, Dongjun; Shatta, Arwa; Kim, Ju Yeong; Holzapfel, Wilhelm H.; Yoon, Hongsup Abstract: Clostridioides difficile infection (CDI) is a major cause of antibiotic-associated diarrhea and colitis, driven by toxin-mediated epithelial injury and inflammation. While antibiotics such as vancomycin remain the primary treatment, they can further disrupt the gut microbiota and promote recurrence. Probiotics, including yeast strains, have emerged as potential adjunctive therapies for mitigating CDI. In this study, several Saccharomyces cerevisiae strains were evaluated for their probiotic potential, and strain 48338 was identified as the most promising candidate based on its gastrointestinal tolerance, auto-aggregation ability, and antioxidant activity. Using a CDI mouse model, we found that treatment with S. cerevisiae 48338 reduced disease severity, as reflected by lower clinical sickness scores. Quantitative PCR analysis confirmed that the expression of the toxin gene tcdA was significantly decreased following 48338 treatment, whereas total C. difficile burden remained unchanged. In addition, 48338 treatment might enhance intestinal barrier integrity by upregulating occludin gene expression and also might attenuate production of pro-inflammatory cytokines, particularly the expression of IL-1 beta. The strain also increased the proportions of Foxp3+ regulatory T cells and macrophages in both the spleen and mesenteric lymph nodes, as determined by flow cytometry, suggesting a shift towards an anti-inflammatory immune profile. Collectively, these findings suggest that the primary mechanism by which S. cerevisiae 48338 exerts its protective effect against C. difficile infection is not through direct reduction of C. difficile colonization, but primarily through modulation of the microbiome, host immune response, and maintenance of epithelial cell integrity. This study highlights the potential of yeast-based probiotics as adjunctive agents for the prevention or mitigation of CDI. Sun, 01 Mar 2026 00:00:00 GMT https://ir.ymlib.yonsei.ac.kr/handle/22282913/211646 2026-03-01T00:00:00Z https://ir.ymlib.yonsei.ac.kr/handle/22282913/211695 Title: IKK2, calcium, MAP kinase, and PI3 kinase are required for exocytosis and interleukin-8 production in human mast cells stimulated by Trichomonas vaginalis-derived secretory products Authors: Park, Shin Hye; Lee, Young Ah; Shin, Myeong Heon Abstract: Trichomonas vaginalis infection causes vaginitis and cervicitis in women, and asymptomatic urethritis and prostatitis in men. Mast cells play a key role in the inflammatory response against T. vaginalis infection. In this study, we examined the signaling pathways involved in mast cell activation induced by T. vaginalis-derived secretory products (TvSP), focusing on IKK2, calcium, MAP kinase (MAPK), and PI3 kinase (PI3K). TvSP stimulation induced phosphorylation and degradation of I kappa B, indicating NF-kappa B activation, and triggered phosphorylation of ERK1/2, p38 MAPK, and AKT. TvSP also increased the surface expression of CD63, a marker of exocytosis, which was reduced by IKK inhibition, calcium chelation, or blockade of PI3K and PKC. Furthermore, inhibition of PI3K or MAPKs decreased TvSP-induced interleukin-8 production. These results suggest that IKK2 and calcium are critical forTvSP-induced degranulation, while PI3K and MAPK pathways contribute to inter-leukin-8 production in mast cells. Thu, 01 Jan 2026 00:00:00 GMT https://ir.ymlib.yonsei.ac.kr/handle/22282913/211695 2026-01-01T00:00:00Z