Black phosphorus quantum dots prevent atherosclerosis in high-fat diet-fed apolipoprotein E knockout mice.

Atherosclerosis (AS) is the main pathological basis of cardiovascular diseases such as coronary heart disease. Black phosphorus quantum dots (BPQDs) are a novel nanomaterial with good optical properties and biocompatibility, which was applied in the treatment of AS in mice, with good results shown in our previous study. In this study, BPQDs were injected into high-fat diet-fed apolipoprotein E knockout mice as a preventive drug for 12 weeks. Simvastatin, a classic preventive drug for AS, was used as a control to verify the preventive effect of BPQDs. The results showed that after preventive treatment with BPQDs, the plaque area in mice was significantly reduced, the vascular elasticity was increased, and serum lipid levels were significantly lower than those in the model group. To explore the mechanism, macrophages were induced to become foam cells using oxidized low-density lipoprotein. We found that BPQDs treatment could increase cell autophagy, thereby regulating intracellular lipid metabolism. Taken together, these data revealed that BPQDs may serve as a functional drug in preventing the development of AS.

Molecular level study of hot water extracted green tea buried in soils - a proxy for labile soil organic matter.

Understanding the composition of soil organic matter (SOM) is vital to our understanding of how soils form, evolve and respond to external stimuli. The shear complexity of SOM, an inseparable mixture of thousands of compounds hinders the determination of structure-function relationships required to explore these processes on a molecular level. Litter bags and soil hot water extracts (HWE) have frequently been used to study the transformation of labile SOM, however these are still too complex to examine beyond compound classes. In this work, a much simpler mixture, HWE buried green tea, was investigated by Nuclear Magnetic Resonance (NMR) spectroscopy and Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS), as a proxy for labile SOM. Changes induced by the burial over 90 days in a grassland, woodland and two peatland sites, one damaged by drainage and one undergoing restoration by drain-blocking, were analysed. Major differences between the extracts were observed on the level of compound classes, molecular formulae and specific molecules. The causes of these differences are discussed with reference to abiotic and biotic processes. Despite the vastly different detection limits of NMR and MS, chemometric analysis of the data yielded identical separation of the samples. These findings provide a basis for the molecular level interrogation of labile SOM and C-cycling processes in soils.

Effect of heat treatments and homogenisation pressure on the acid gelation properties of recombined whole milk.

The homogenisation pressure and the order of heating and homogenisation were varied in the preparation of recombined whole milks. The fat globule sizes decreased from ∼2 to 0.2µm as the homogenisation pressure increased from 50 to 850bar for samples heated before (HEHO) or after (HOHE) homogenisation. For acid gels prepared from the milks, small increases in elastic modulus of the set gels were observed with decreasing fat globule size. The yield strain of the acid gels increased linearly with decreasing fat globule size, and HOHE gels had higher yield strains than HEHO gels. The yield stress of the set gels increased with decreasing fat globule size, and the yield stress for HOHE gels were higher than the HEHO gels. Confocal micrographs of the gels revealed an almost continuous protein network structure without pores for gels from milks treated at low homogenisation pressures, and the large fat globules did not actively interact with the strands in the gel network. In contrast, a porous protein network structure with distinct strands was observed for the samples treated at high homogenisation pressures, and the small fat globules were intimately involved in the strands in the network structure. The HOHE gels had a more porous protein network with thicker strands than the HEHO gels. The size of the fat globules and their incorporation in the protein network during acidification is proposed to affect the acid gel structure and properties.