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Tetrabromobisphenol A (TBBPA) is a global pollutant. When TBBPA is absorbed by the body through various routes, it can have a wide range of harmful effects on the body. Green tea polyphenols (GTPs) can act as antioxidants, resisting the toxic effects of TBBPA on animals. The effects and mechanisms of GTP and TBBPA on oxidative stress, inflammation and apoptosis in the mouse lung are unknown. Therefore, we established in vivo and in vitro models of TBBPA exposure and GTP antagonism using C57 mice and A549 cells and examined the expression of factors related to oxidative stress, autophagy, inflammation and apoptosis. The results of the study showed that the increase in reactive oxygen species (ROS) levels after TBBPA exposure decreased the expression of autophagy-related factors Beclin1, LC3-II, ATG3, ATG5, ATG7 and ATG12 and increased the expression of p62; oxidative stress inhibits autophagy levels. The increased expression of the pro-inflammatory factors IL-1β, IL-6 and TNF-α decreased the expression of the anti-inflammatory factor IL-10 and activation of the NF-κB p65/TNF-α pathway. The increased expression of Bax, caspase-3, caspase-7 and caspase-9 and the decreased expression of Bcl-2 activate apoptosis-related pathways. The addition of GTP attenuated oxidative stress levels, restored autophagy inhibition and reduced the inflammation and apoptosis levels. Our results suggest that GTP can attenuate the toxic effects of TBBPA by modulating ROS, reducing oxidative stress levels, increasing autophagy and attenuating inflammation and apoptosis in mouse lung and A549 cells. These results provide fundamental information for exploring the antioxidant mechanism of GTP and further for studying the toxic effects of TBBPA.

In this work, a fluorescent probe, TPABF-HS, was developed for detecting hydrogen sulfide (H 2 S) using a human serum albumin (HSA)-binding-based approach for amplifying the fluorescence signal and extending the linear correlation range. Compared to the most recent probes for H 2 S, the most interesting feature of the detection system developed herein was the especially wide linear range (0-1000 μM (0-100 eq.)), which covered the physiological and pathological levels of H 2 S. TPABF-HS could be used in applications high sensitivity and selectivity with an LOD value of 0.42 μM. Further, site-competition experiments and molecular docking simulation experiments indicated that signal amplification was realized by the binding of the TPABF fluorophore to the naproxen-binding site of HSA. Moreover, the extension of the measurement span could allow for applications in living cells and Caenorhabditis elegans for imaging both exogenous and endogenous H 2 S. This work brings new information to the strategy of signal processing by exploiting fluorescent probes.

A two-dimensional Cd(ii) metal-organic framework (MOF) was constructed from a tris(pyridinium)-based hexacarboxylate zwitterionic ligand. The MOF shows a novel fashion of 2-fold 2D → 2D parallel entanglement. It is the entanglement that dictates close interlayer contacts between carboxylate (electron donor) and pyridinium (acceptor), which in turn impart the MOF with reversible photochromic properties through photoinduced electron transfer (PET). This is an extension of PET-based photochromism from bipyridinium to multipyridinium compounds. Thanks to the photoresponsive behaviour, the fluorescence of the MOF can be reversibly modulated or switched by photoirradiation. Besides, the fluorescence of the water-stable MOF in aqueous dispersion is very sensitive to nitrofuran antibiotics with high selectivity, and therefore the MOF is a good candidate of efficient and regenerable sensing material for determination of the antibiotics in water media.

The Zn(ii) MOF with a tripyridinium-based hexacarboxylate shows direct color change on exposure to small primary amines and UV-assisted color response on exposure to small alcohols. The reversible, group-specific and size-selective chemochromic/chemophotochromic behaviours are ascribed to spontaneous/photoinduced guest-to-host electron transfer within the unique confined space furnished with electron-deficient sites.

Selenium (Se) is an essential trace element for living organisms and plays diverse biological roles. Endometritis is a common reproductive disorder in dairy cows, causing huge economic losses. In this study, we explored the effects of Se on lipopolysaccharide (LPS)-induced endometritis in mice and expounded its underlying mechanism of action. We validated the anti-inflammatory effects of Se in vivo by establishing a mouse model of endometriosis induced by LPS. Se significantly reversed the LPS-induced uterine histopathological changes, MPO activity and inflammatory cytokine levels in vivo. Simultaneously, TLR4 and its downstream signaling pathways, lipid rafts and cholesterol levels in the tissues were also attenuated by Se under LPS stimulation. In addition, the molecular mechanism of the Se anti-inflammatory effect was clarified in mouse endometrial epithelial cells. Se inhibited TLR4-mediated NF-κB and IRF3 signal transduction pathways to reduce the production of inflammatory factors. We found that Se promoted the consumption of cholesterol to suppress the lipid rafts coming into being and inhibited the TLR4 positioning to the lipid raft to prevent the inflammatory response caused by LPS. Meanwhile, Se activated the LxRα-ABCA1 pathway to cause the outflow of cholesterol in cells. The anti-inflammatory effect of Se was disrupted by silencing LxRα. In conclusion, Se exerted anti-inflammatory effects most likely by the LxRα-ABCA1 pathway activation, which inhibited lipid rafts by depleting cholesterol and ultimately impeded the migration of TLR4 to lipid rafts.

Mastitis, a major disease affecting dairy cows, is most commonly caused by Staphylococcus aureus (S. aureus). Selenium (Se) can activate pivotal proteins in immune responses and regulate the immune system, and microRNA-155 (miR-155) is a key transcriptional regulator for inflammation-related diseases. We constructed the model of mouse mastitis in vivo and primary mouse mammary epithelial cells (MMECs) in vitro, which were induced by S. aureus. Se content of the mammary was estimated using an atomic fluorescence spectrophotometer. Histopathological analysis was performed via hematoxylin and eosin (H&E) staining. The mmu-miR-155-5p mimic was transfected in MMECs, and viability was determined through the MTT assay. Transfected efficiency was evaluated by qPCR and fluorescence staining. Cytokines including TNF-α, IL-1β, IL-10 and TLRs were detected with qPCR. In addition, western blotting was used to evaluate the expression of the NF-κB and MAPKs signaling pathways. The results demonstrated that a Se-supplemented diet improved the content of Se in mammary tissues. Histopathological studies indicated that the mammary glands were protected in the Se-supplemented group after S. aureus infection. Se-supplementation suppressed the production of MPO, mmu-miR-155, TNF-α, IL-1β, and TLR2 and significantly inhibited the phosphorylation of NF-κB and MAPKs in vivo and in vitro. All the data indicated that mmu-miR-155 played a pro-inflammatory role in our study, and Se-supplementation could suppress the expression of mmu-miR-155 to inhibit inflammation in S. aureus-induced mastitis in mice.

Nine novel heterometallic coordination polymers [Ln(2)Ni(Hbidc)(2)(SO(4))(2)(H(2)O)(8)](n) (Ln = Pr (1), Sm (2), Eu (3), Gd (4), Tb (5), Dy (6), Ho (7), Er (8), Yb (9), H(3)bidc = 1H-benzimidazole-5,6-dicarboxylic acid) have been synthesized under hydrothermal conditions and characterized by elemental analysis, FT-IR, TG analysis and single crystal X-ray diffraction. X-ray analysis revealed that all complexes present almost identical three-dimensional (3D) structures with PtS-type topology. Complexes 1-7 are all isomorphous, and the structure variation of polymers 8 and 9 is induced by the lanthanide contraction effect. In additional, the luminescence properties of complexes 2, 3 and 5-7, and the magnetic properties of complexes 4 and 6-8 were investigated.

Mesoporous TiO(2) spheres with a large surface area and rich surface hydroxyl groups have been prepared through a light-driven synthetic strategy, and the as-prepared mesoporous material is able to convert urea to carbon nitride efficiently under a mild condition.

Seven novel heterometallic coordination polymers [CeAg(Hbidc)(2)(H(2)O)(2)] (1) and [LnAg(Hbidc)(2)]·3(H(2)O)[Ln = Sm (2), Gd (3), Tb (4), Dy (5), Ho (6), Er (7), H(3)bidc = 1H-benzimidazole-5,6-dicarboxylic acid] have been synthesized under hydrothermal conditions and characterized by elemental analysis, FT-IR, TG analysis, and single crystal X-ray diffraction. X-Ray analysis revealed that the seven complexes present two different types of three-dimensional (3D) structures. Complex 1 crystallized in an orthorhombic manner having a Pna2(1) space group, consisting of a 3D framework with a 1D heterometallic chain. Polymers 2-7 are isostructural and crystallized in an orthorhombic fashion having a Pccn space group existing of a two-fold interpenetrating 3D framework. The luminescence properties and the magnetic properties of all polymers were investigated.