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This study aimed to establish the mode of binding between Quercetin (QEN) and an essential protein called ClfB in forming biofilm in Staphylococcus aureus (S. aureus). In this study, the raw data of GSE163153 were analyzed for quality control, alignment, and gene counts, and the differential analysis detected the key differentially expressed genes (DEGs) assisting in the formation of the S. aureus biofilm. Then, the protein-protein interaction (PPI) and gene function enrichment analyses of the target genes, identified a gene called clfB to be closely related to biofilm formation. ClfB was structurally characterized, molecularly docked, and kinetically simulated to unravel the mode of binding of QEN to ClfB. Meanwhile, the growth curve and transmission electron microscopy methods examined the effect of QEN on the S. aureus growth. Results indicated that the clfB gene was increasingly expressed during biofilm formation and was involved in cell adhesion, pathogenicity, and infection. We identified 5 amino acid sites of ClfB (D272, R331, I379, K391, E490) as potential sites for binding QEN, which would indirectly influence the changes in the functional sites N234, D270, Y273, F328, inhibiting the formation of biofilm. Meanwhile, 128 μg/ml of QEN could significantly inhibit the S. aureus biofilm formation. This manuscript serves as a molecular foundation for QEN as an antibacterial drug providing a new perspective for developing antibacterial drugs.

The inflammatory response to chronic injury affects tissue regeneration and has become an important factor influencing the prognosis of patients. In previous stem cell treatments, it was revealed that stem cells not only have the ability for direct differentiation or regeneration in chronic tissue damage but also have a regulatory effect on the immune microenvironment. Stem cells can regulate the immune microenvironment during tissue repair and provide a good “soil” for tissue regeneration. In the current study, the regulation of immune cells by mesenchymal stem cells (MSCs) in the local tissue microenvironment and the tissue damage repair mechanisms are revealed. The application of the concepts of “seed” and “soil” has opened up new research avenues for regenerative medicine. Tissue engineering (TE) technology has been used in multiple tissues and organs using its biomimetic and cellular cell abilities, and scaffolds are now seen as an important part of building seed cell microenvironments. The effect of tissue engineering techniques on stem cell immune regulation is related to the shape and structure of the scaffold, the preinflammatory microenvironment constructed by the implanted scaffold, and the material selection of the scaffold. In the application of scaffold, stem cell technology has important applications in cartilage, bone, heart, and liver and other research fields. In this review, we separately explore the mechanism of MSCs in different tissue and organs through immunoregulation for tissue regeneration and MSC combined with 3D scaffolds to promote MSC immunoregulation to repair damaged tissues.

The effect of replacing fish meal with raw and various processed soybeans meal on growth and protein metabolism of common carp Cyprinus carpio was evaluated in an 8-week trial. The common carp fingerlings[initial body weight(5.89±0.36) g] were fed five isonitrogenous and isocaloric feeds(30% digestible protein and 15 MJ/kg digestible energy) containing SBM replacing 50% of the fish meal protein,such as raw soybean(RSB),processed soybean by chemical inactivator,processed soybean by heating,processed soybean by heat alcohol,respectively. Results showed that weight gain of control were significantly different(P0.05),but those fed RSB were significantly lower than control(P0.05),those fed processed soybeans by chemical inactivator and by heating and by heat alcohol had no significant difference,but all significantly higher than control. Protease specific activity of control in the intestine and hepatopancreas was significantly higher than those fed RSB and processed soybeans by heat alcohol,but both had no significant difference with those fed processed soybeans by chemical inactivator and by heating(P0.05). RNA of 100% fish meal and 50% processed soybean by heating in white muscle were no significant difference(P0.05),but both were significantly higher than those fed RSB and processed soybeans by heat alcohol and by chemical inactivator and by heating,RNA/DNA of 100% fish meal and 50% processed soybean by heating and by chemical inactivator in white muscle had no significant difference(P0.05),but all were higher than those fed raw soybean(RSB) and processed soybean by heat alcohol(P0.05). RNA in white muscle and serum IGF-I had a positive correlation with growth(P0.05).The degree of negative effect of soybean anti-nutritional factors on fish is anti-trypsin inhibitoragglutininsoybean antigen protein under the experimental conditions,and proper control could reduce the negative impact of soybean anti-nutritional factors on fish.

Reported in this paper are the petrology and mineral chemistry of GRV 020090, the second Martian meteorite collected from the Grove Mountains, Antarctica. This meteorite, with a mass of 7.54 g, is completely covered by a black and glazy fusion crust. It has two distinct textural regions. The interstitial region is composed of euhedral grains of olivine, pigeonite, and anhedral interstitial maskelynite, with minor chromite, augite, phosphates and troilite. The poikilitic region consists of three clasts of pyroxenes, each of which has a pigeonite core and an augite rim. A few grains of subhedral to rounded olivine and euhedral chromite are enclosed in the pyroxene oikocrysts. GRV 020090 is classified as a new member of lherzolitic shergottites based on the modal composition and mineral chemistry. This work will shed light on the composition of Martian crust and magmatism on the Mars.

A one-dimensional time-dependent photochemical model is used to simulate the influence of ion-produced NOx and HOx radicals on the Antaratic ozone depletion in polar night and polar spring at a latitude of 73 degrees south.

Raman spectra of YBa 2 Cu 3-x Sn x O 7-y have been obtained for x from 0 to 3. The critical dopant concentration x c for Sn, at which superconductivity disappears, is found to be approximately 1.0. This is in agreement with a metal-insulator transition model in which x c = 1.27. Above x = 1.0, the system is semiconducting up to x = 3.0 (pure Sn), at which it is an insulator. The 506 cm −1 Cu-0 vibration is present for all superconducting samples (x ≤ 1.0) but broadens anomalously as x→1 and is absent for all semiconducting samples.

Onset of superconductivity of the new high Tc superconductor Eu-Ba-Cu-O was found to be 92K. The valence of Eu ion and the Debye temperature of this superconductor were determined using Mossbauer spectroscopy. The experimental results show abnormal changes of isomer shift and lattice-softening nearby the transition temperature Tc. It seems that high Debye temperature is not a necessary condition for this high Tc superconducting system.

The effect of entering of Fe-atoms and Sn-atoms into crystal lattice of permanent magnet SmCo5 on the X-ray diffraction relative intensities is studied. It is observed that the Fe-atoms can replace the Co-atoms on any site, but they replace Co2c more readily.However, the Sn-atoms replace the Co-atoms or 3 g sites more easily. The replacement of Co-atoms by the Sn-atoms can increases the ratio of X-ray diffraction relative intensity I200/I111, but the striking changes of this ratio is largely due to the alignment, the order of Fe, Sn atoms, the improvement of internal stress conditions, and the controlling of the ～750℃ phase transformation.