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Background: Dihydroartemisinin (DHA), a derivative of Artemisia annua, has been shown to possess anti-inflammatory properties. Besides, Yes-associated protein 1 (YAP1) plays a crucial role in maintaining liver homeostasis. Methods: This study used Yap1Flox/Flox, Albumin-Cre mice with hepatocyte-specific Yap1 knockout (referred to as Yap1LKO) and their control mice (Yap1Flox/Flox, referred to as Yap1Flox). The effect of Yap1 on lipid metabolism homeostasis was investigated through non-targeted metabolomic analysis of mouse liver. Subsequently, DHA was administered to Yap1LKO mice to assess its potential as a treatment. Liver pathology was evaluated via H&E staining, and the levels of AST, ALT, and TG were quantified using biochemical assays. The contents of arachidonic acid (AA), prostaglandin E1 (PGE1), and leukotrienes (LT) in the liver were measured using ELISA, while the protein expressions of PLIN2, 5-lipoxygenase (5-LOX), and cyclooxygenase-2 (COX-2) were analyzed through IHC staining. Results: Hepatocyte-specific Yap1 knockout activated the AA metabolic pathway, resulting in increased elevated levels of AA, PGE1, and LT levels, along with inflammatory cytokine infiltration. DHA mitigated the elevation of metabolites such as PGE1 and LT caused by the AA metabolic pathway activation by down-regulating the levels of COX-2 and 5-LOX in the liver of Yap1LKO mice. Moreover, it alleviated the accumulation of lipid vacuoles and reduced triglyceride (TG) and perilipin-2 (PLIN2) levels in the liver of Yap1LKO mice. Conclusions: Excessively low YAP1 expression induces liver inflammation and disturbances in lipid metabolism, whereas DHA modulated AA metabolism and mitigated liver inflammation by inhibiting the activation of 5-LOX and COX-2.

Droplet evaporation is widely present in nature and industrial production, involving heat and mass transfer between the droplet and the surrounding gas environment. This study investigates the evaporation of individual spherical droplets in a high-temperature gas environment under both stationary and forced convection conditions, using theoretical and numerical approaches. The results show that the established evaporation model can effectively reflect the temperature change during droplet evaporation. When the droplet evaporates in a gaseous environment, the equilibrium temperature of the droplet is influenced by environmental parameters such as temperature and humidity. Compared to environmental temperature, humidity has a more significant impact on the equilibrium temperature of the droplet, making it the dominant factor affecting the evaporation temperature. The evaporation rate of the droplet is influenced by environmental humidity. When the air humidity is below 0.5, the variable-rate evaporation aligns closely with the numerical simulation results (droplet lifetime). When the air humidity is above 0.5, the simulation results are slightly higher but still have a small relative error. As the environmental humidity increases, the evaporation rate of the droplet is suppressed, leading to an increase in its lifetime. Establishing an appropriate droplet evaporation model not only deepens our understanding of the internal mechanisms of droplet evaporation but also provides practical guidance for enhancing heat and mass transfer in droplets.

Melamine is widely used to make household products including plates, cups, and large-scale industrial plastic products. Studies have shown the nephrotoxicity of melamine. However, little is known about urinary melamine concentration in adults and its association with the consumption of foods, other than milk products. In this study, we measured the urinary melamine concentration of 908 Shanghai adults and calculated the estimated daily intake (EDI) and hazard quotient accordingly. We also used a 24 h (24-hr) recall survey to identify possible risk foods associated with melamine exposure. Melamine was detectable in over 85% of the urine samples and had a median concentration of 2.524 μg/g. There were 22 participants who had EDIs exceeding the tolerable daily intake (TDI) of 3150 ng/kg bw/day, the strictest reference dose in administration by far. Melamine concentration in urine was positively associated with the 24-hr recall consumption of rice, fruits, beef, mutton, processed meats, and eggs, but no other food categories. Our study provides evidence-based data on the melamine exposure level in adults from Shanghai, China, and some possible associations with food intake. Keywords: Melamine, Estimated daily intake, Hazard quotient, Food consumption, 24-hr recall survey