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The intestinal epithelial layer forms a barrier through cell-cell tight junctions and breaking or even slightly disrupting this barrier can lead to serious pathological consequences, including infection and inflammation. Various amino acids have been shown to improve the intestinal tract, but the effect of tryptophan on the intestinal barrier has been controversial. Here, an in vitro Caco-2 cell model was built to investigate the protective and reparative effects of different concentrations of dietary l-Tryptophan (l-Trp) on lipopolysaccharide (LPS)-induced intestinal tight junction injury. Lower concentrations (40 μM) of dietary l-Trp protected and repaired the integrity and permeability injury of the intestinal tight junction induced by LPS, while high concentrations (80 μM) may not have a positive effect. LPS-induced injury led to increased (P0.05) mRNA expression of Nuclear factor-kappa B (NFκB) and Myosin light-chain kinase (MLCK), and decreased (P0.05) the mRNA expression of extracellular regulated protein kinase 1/2 (ERK1/2) and Mitogen-activated protein (MAP), and the treatment of dietary l-Trp alleviated those regulations in different concentrations, which suggests that dietary l-Trp may attenuate LPS-induced injury to tight junctions via inhibiting the NFκB-MLCK signaling pathway and activating the ERK1/2-MAP signaling pathway. And the mRNA and protein expressions of claudin-1, occludin and ZO-1 in LPS-induced injury were all down-regulated to varying degrees, and dietary l-Trp weakened the down-regulation of claudin-1 (P0.05) with no significant regulation of the protein expression of occludin and ZO-1 (P0.05).

The application of sodium percarbonate (SPC) catalyzed by FeOCl under visible light (FeOCl/SPC/Vis), is shown in this paper. The reaction kinetics, degradation mechanism, and catalyst stability were thoroughly investigated using Rhodamine B (RhB) as a simulated pollutant. Experimental results show that the degradation rate of RhB increases due to the participation of visible light. The valence change of iron species in the FeOCl catalyst, before and after the reaction, were characterized by XPS. It is found that the redox cycle of iron species can be accelerated under visible light. This activates SPC to generate radicals, effectively.

Activation of persulfate (PS) by ultraviolet light or transition metal catalysts has been extensively studied. However, little is known about the activation of PS by iron oxychloride (FeOCl) in the presence of visible light irradiation. Herein, the catalytic activity of FeOCl was developed for oxidative degradation of rhodamine B (RhB) with the FeOCl/PS/Vis process. The characterization of FeOCl for reaction kinetics, degradation mechanism, and catalyst stability was investigated. It is found that the redox cycle of iron species and photoinduced electrons formed on the FeOCl catalyst surface can effectively activate PS, to generate radicals. Based on quenching experiments and electron paramagnetic resonance, the photogenerated holes (h+) and sulfate radicals (SO4−•) are the predominant reactive oxidants for RhB decolorization, while superoxide radicals (•O2−) and hydroxyl radicals (•OH) are also involved. Moreover, FeOCl shows good catalytic performance in a wide range of pH values (pH = 3–10) and excellent reusability and stability, as well.

The square-sharped BiOCl nanosheets with oxygen vacancies were successfully synthesized via a facile hydrothermal route using xylitol as surfactant. The as-prepared BiOCl samples were characterized by Powder X-ray Diffractometer (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), UV–Vis diffuse reflectance spectra (DRS), Brunauer–Emmett–Teller (BET), X-ray photoelectron spectroscopy (XPS) and Electron spin resonance (ESR). The as-prepared samples were phase-pure with the width and the thickness were about 50–400 nm and 20–50 nm respectively. Besides, the photodegradation performances showed the BiOCl nanosheets with 0.1 g concentration of xylitol (BOC-1) had the best photocatalytic activity under visible light due to its special polycrystalline structure, grain boundary and an optimum concentration of oxygen vacancies. The h+ and O2− were the two main active species during the photocatalytic process and the possible photocatalytic mechanism was proposed.

FeOCl was prepared by a partial thermal decomposition method to effectively catalyze hydrogen peroxide under the visible light for the degradation of toxic organic wastewater. The combination of DRS and VB-XPS indicated that FeOCl is a narrow band gap catalyst with visible light absorption capacity (Eg =1.63 eV). The degradation rate constant of RhB in FeOCl/H2O2/Vis system is about 13.4 times that of FeOCl/H2O2 system. Compared to other heterogeneous Photo-Fenton systems, the oxidant utilization efficiency in FeOCl/H2O2/Vis system is higher. In addition, FeOCl has stable Photo-Fenton activity in a wide pH range (3.0–9.0). The content of Fe(II) increased after 5 cycles reaction through the ESR and XPS characterization, which proves that the electron transfer of Fe(III)/Fe(II) was improved during the reaction. After quantitative analysis of the ·OH generated in the reaction, the formation rate of ·OH in FeOCl/H2O2/Vis system is increased about 30% compared with FeOCl/H2O2/dark system. These results indicate that visible light excites FeOCl to generate produces photogenerated electron-hole pairs, accelerating the cycle of Fe(III)/Fe(II), promoting the production rate of ·OH, and enhancing the catalytic efficiency of FeOCl.

Few studies have evaluated the morbidity burden of cardiovascular diseases (CVDs) due to coarse particulate matter (PMC, particles with an aerodynamic diameter between 2.5 and 10 μm) pollution, especially in a multi-city setting. This study aimed to investigate the short-term impacts of PMC on hospital admissions (HAs) for total and cause-specific CVDs in 18 cities of Sichuan Province, Southwestern China during 2015–2016, and calculate the corresponding attributable risks. First, generalized additive model (GAM) was employed to estimate the city-specific associations of PMC with CVDs hospitalizations, and then combined the results from the single cities to obtain the pooled effects at the regional level. Age-, sex- and season-specific analyses were also performed. We further estimated the burden of HAs for CVDs attributable to PMC exposure. A total of 621,835 HAs for CVDs were collected during the study period. We found that PMC was significantly associated with elevated risks of CVDs hospitalizations. Per 10 μg/m3 increase in PMC corresponded to an increase of 1.18% (95% CI: 0.67%–1.68%) in daily HAs for CVDs. For specific subtypes of CVDs, significant associations of PMC with acute myocardial infarction, heart failure and ischemic stroke were observed. The effect estimates of PMC remained robust after adjusting for PM2.5 (particles with an aerodynamic diameter ≤ 2.5 μm) and gaseous pollutants in co-pollutant models. The pernicious effects were found to be stronger in the elderly and in the warm season. Overall, about 1.26% (95% CI: 0.73%–1.79%) of HAs for CVDs could be attributable to PMC exposure, corresponding to 7863 (95% CI: 4554–11110) attributable CVDs HAs. Our findings suggest that PMC might result in increased risk of HAs for CVDs in Sichuan Province, Southwestern China, and should be considered in the prevention and control of CVDs.