RESUMEN
Staphylococcus aureus (SA) is a major cause of sepsis, leading to acute lung injury (ALI) characterized by inflammation and oxidative stress. However, the role of the Nrf2/PHB2 pathway in SA-induced ALI (SA-ALI) remains unclear. In this study, serum samples were collected from SA-sepsis patients, and a SA-ALI mouse model was established by grouping WT and Nrf2-/- mice after 6 h of intraperitoneal injection. A cell model simulating SA-ALI was developed using lipoteichoic acid (LTA) treatment. The results showed reduced serum Nrf2 levels in SA-sepsis patients, negatively correlated with the severity of ALI. In SA-ALI mice, downregulation of Nrf2 impaired mitochondrial function and exacerbated inflammation-induced ALI. Moreover, PHB2 translocation from mitochondria to the cytoplasm was observed in SA-ALI. The p-Nrf2/total-Nrf2 ratio increased in A549 cells with LTA concentration and treatment duration. Nrf2 overexpression in LTA-treated A549 cells elevated PHB2 content on the inner mitochondrial membrane, preserving genomic integrity, reducing oxidative stress, and inhibiting excessive mitochondrial division. Bioinformatic analysis and dual-luciferase reporter assay confirmed direct binding of Nrf2 to the PHB2 promoter, resulting in increased PHB2 expression. In conclusion, Nrf2 plays a role in alleviating SA-ALI by directly regulating PHB2 transcription and maintaining mitochondrial function in lung cells.
RESUMEN
Diabetic kidney disease (DKD) is one of the major chronic complications of diabetes mellitus (DM), as well as a main cause of end-stage renal disease. Over the last few years, substantial research studies have revealed a contributory role of gut microbiota in the process of DM and DKD. Metabolites of gut microbiota like lipopolysaccharide, short-chain fatty acids, and trimethylamine N-oxide are key mediators of microbial-host crosstalk. However, the underlying mechanisms of how gut microbiota influences the onset and progression of DKD are relatively unknown. Besides, strategies to remodel the composition of gut microbiota or to reduce the metabolites of microbiota have been found recently, representing a new potential remedial target for DKD. In this mini-review, we will address the possible contribution of the gut microbiota in the pathogenesis of DKD and its role as a therapeutic target.
RESUMEN
Based on a geo-weighted regression model, this study analyzes the relationship between the landscape patterns of sources and sinks in urban areas and atmospheric haze pollution. First, the classification result of the study area is divided into a number of square grids with side lengths of 2-9 km. Heterogeneity indices at different scales are calculated and compared to select an optimal scale for the following analysis. Then, the category level landscape indices, such as PLAND, PD, COHEDION, LPI, and FRAC_MN, are calculated in each grid. The aerosol optical thickness (AOD) of Wuhan is used to represent the degree of atmospheric haze pollution. Furthermore, the mean value of the pixels in each grid is regarded as the value of the grid's center. Next, the landscape sources and sinks of atmospheric haze pollution are selected based on the analysis of the correlation between landscape indices and AOD. To make the following analysis more efficient, the indices selected previously are determined using their correlation coefficients. Finally, the geo-weighted regression analysis model is used to analyze the relationship between the landscape indices of the category level and AOD. In addition, the influences of industrial, commercial, and residential areas on haze pollution are analyzed based on the result of the classification of urban functional areas. The results show that the heterogeneity of the whole landscape is most obvious at a 6 km scale, so 6 km is the optimal scale for the analysis. The landscape sources of atmospheric haze pollution are the buildings, and the landscape sinks are shrubs and woodland. Reducing the proportion of landscape source area and increasing the degree of fragmentation can cut down aerosol optical thickness. Distributing the landscape sources and sinks evenly and interspersedly could effectively reduce aerosol optical thickness, which represents atmospheric haze pollution. For Wuhan City, the main sources of haze pollution are commercial and residential areas in the city center, representing public sources. Since it is not easy to adjust existing facilities and infrastructure, adjusting built-up areas slightly and planning reasonably for those areas that are not yet built up can reduce atmospheric haze pollution.
RESUMEN
The pricing problem of lookback option with a fixed proportion of transaction costs is investigated when the underlying asset price follows a fractional Brownian motion process. Firstly, using Leland's hedging method a partial differential equation satisfied by the value of the lookback option is derived. Then we obtain its numerical solution by constructing a Crank-Nicolson format. Finally, the effectiveness of the proposed form is verified through a numerical example. Meanwhile, the impact of transaction cost rate and volatility on lookback option value is discussed.
