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Aim: To obtain promising immunosuppressants from endophytic fungus. Methods and Results: The endophytic fungus Mycosphaerella nawae (ZJLQ129) was isolated from the plant Smilax china L. and its secondary metabolites extracted and fractionated through column chromatography. The metabolites were further modified by a derivatization reaction with ammonium hydroxide. After isolation and derivatization, a new dibenzofuran named as (+)isomycousnine enamine (iME) was obtained. The structures of the derivatives were determined based on chemical evidences and extensive spectroscopic methods including 2D‐NMR, DEPT and HRESI‐MS spectra. The immune activities of iME were first evaluated on the proliferation and cytokines (IL‐2 and IFN‐γ) production of T and B cells by using MTT and ELISA methods respectively. Then, its effects on the proliferation of T‐cell subsets (CD4+ and CD8+ T cells), as well as CD25 and CD69 expressions were also determined by flow cytometry. Finally, by using Cytometric Bead Array (CBA), the impacts of iME on the secretion of Th1/Th2/Th17 cytokines from purified CD4+ T cells were assayed. The results showed that iME not only selectively suppressed the immune responses of T cells, but also preferentially inhibited the activation and proliferation of CD4+ T cells. Conclusion: A novel dibenzofuran derived from endophytic fungus Mycosphaerella nawae preferentially inhibits CD4+ T‐cell activation and proliferation. Significance and Impact of the Study: This work obtained iME, a new dibenzofuran derived from endophytic fungus. iME has the capacity to inhibit CD4+ T‐cell activation and therefore is a novel potential immunosuppressant for development in the future. [ABSTRACT FROM AUTHOR]

Aims: In recent years, the incidence rate of hypertensive intracerebral haemorrhage (HICH) has been increasing, accompanied by high mortality and morbidity, which has brought a heavy burden to the social economy. However, the pathogenesis of HICH is still unclear. This study intends to explore the mechanism of gut microbiota metabolism and inflammation in the process of HICH to provide a theoretical basis for the diagnosis and treatment of HICH. Methods and Results: HE staining showed that the brain tissues of model group had obvious oedema injury, which indicated that the HICH model was successfully constructed. ELISA analysis showed that IL‐1β and TNF‐α levels in blood and brain tissues were significantly increased, and IL‐10 level was significantly decreased in blood. IHC analysis showed that microglia and macrophages were activated in the model group. 16S rRNA sequence showed that the diversity of gut microbiota in HICH patients decreased. Also, the microbiota belonging to Firmicutes, Proteobacteria and Verrucomicrobia changed significantly. LC–MS/MS analysis showed that the metabolic phenotype of HICH patients changed. Also, the 3,7‐dimethyluric acid‐ and 7‐methylxanthine‐related metabolic pathways of caffeine metabolism pathways were downregulated in patients with HICH. Bacteroides was negatively correlated with the IL‐1β and TNF‐α levels. Blautia was negatively correlated with the IL‐1β and TNF‐α levels, and positively correlated with the IL‐10 level. Akkermansia was negatively correlated with the 3,7‐dimethyluric acid and 7‐methylxanthine. Conclusion: Our study suggested that HICH was accompanied by the increased inflammation marker levels in peripheral blood and brain, decreased gut microbiota diversity, altered gut metabolic phenotype and downregulation of caffeine metabolism pathway. Significance and Impact of the Study: Our study reported that HICH accompanied by the increased inflammation, decreased gut microbiota diversity and altered gut metabolic phenotype. Due to the number of patients, this work was a pilot study. [ABSTRACT FROM AUTHOR]

Aims: We investigated the fate of Salmonella in lettuce seeds grown in a hydroponic system and the potentials of applying photodynamic inactivation (PDI) to enhance microbial safety of hydroponic farming systems. Methods and Results: Lettuce was grown from Salmonella‐contaminated seeds, and rose bengal‐mediated PDI was applied. Without intervention, Salmonella could persist in plants and hydroponic farming environment throughout 6 weeks of lettuce growth. Cross‐contamination from Salmonella‐inoculated to noninoculated seedlings was observed. PDI significantly decreased Salmonella from 3.90 ± 0.31 log colony‐forming unit (CFU) per plant to 2.77 ± 0.49 log CFU per plant without extra illumination needed (p < 0.01) by week six. Conclusions: Salmonella from contaminated seeds could survive for an extended period in lettuce and hydroponic farming environment and posed serious cross‐contamination risks. Rose bengal‐mediated PDI showed promise in controlling Salmonella contamination in lettuce in a hydroponic farming setting. Significance and Impact of the Study: This study shed light on the serious food safety implications that Salmonella‐contaminated lettuce seeds might entail in a hydroponic farming environment and demonstrated rose bengal‐mediated PDI as a potential mitigation strategy. These findings contribute to the increasingly relevant field of urban farming systems and their associated food safety concerns. [ABSTRACT FROM AUTHOR]