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Streptococcus pneumoniae is a pathogen that causes community-associated infections in young children Whole-genome sequencing (WGS) has become a powerful tool for bacterial genotyping; costs have been decreasing as accessibility increases. [...]

Objective To analyze the modeling elements and subjects of the animal model of skin photoaging, and to provide a reference for the preparation and improvement of the model and a basis for the scientific evaluation of the subject. Methods By searching and collecting relevant literature on the preparation of animal models of skin photoaging from 2010 to 2022 in the China National Knowledge Infrastructure, Wanfang Database, and PubMed database, the model animal species, gender, modeling method, modeling cycle, radiation source and its distance from the modeling site, cumulative radiation volume, detection indicators, and subjects (drugs or treatments) recorded in the literature were collated and summarized, and a database was established for statistical analysis. Results 257 articles that met the inclusion criteria were selected. Among them, the most common animal model was SKH-1 hairless mice, followed by SD rats and KM mice; the gender of animals was mainly female, medium-wave ultraviolet B (UVB) was often used as the radiation source, the distance between the radiation source and the modelling site was mostly 30 cm, and the modelling period was usually 40-60 days. The cumulative dose of long-wave ultraviolet A (UVA) was between 100-150 J/cm2, and the cumulative dose of UVB was between 5-10 J/cm2. The tests used after model establishment were skin histopathological examination, skin tissue homogenization, fibre staining, immunoblotting, etc. Subjects included Chinese herbal medicines, Chinese herbal extracts, Chinese patent medicines, Chinese herbal compound medicines, chemical drugs, biological agents and other treatments, while the animal model of skin photoaging was also used for clinical efficacy studies of external Chinese medicine, physiotherapy and positive control drugs. Conclusion In skin photoaging animal experiments, female SKH-1 hairless mice are often used, and UVB is used as the radiation source. The modeling period is usually 40-60 days, and the minimum erythema dose (MED) is incremented week by week. The cumulative UVB irradiation dose ranges from 0 to 10 J/cm2, which has the advantages of high success rate, good reproducibility and high similarity with clinical disease.

The effects of different concentrations (0%–20%) of soybean oil or lard added to pomfret surimi gel on its physicochemical properties and protein structure were studied. The addition of 8% lard or soybean oil significantly increased the whiteness, water-holding capacity (WHC), gel strength, storage modulus (G’) and sensory evaluation of surimi. When the addition level was higher than 8%, the strength, WHC, and G’ decreased. Surimi gel with 8% lard was better than that with the same concentration of soybean oil. The results of scanning electron microscopy (SEM) showed that lipids not only filled the void between protein molecules, but also formed an interfacial protein film on the surface, which combined with the protein matrix through protein filaments. It was shown that there was an interaction between lipids, the interfacial protein membrane and proteins in surimi gels. Raman spectra showed that the addition of lipids decreased the relative content of α-helix, and the first increases and then decreases of β-sheet. The addition of soybean oil also significantly increased the relative content of random coils, while the change in random coils of lard was not as significant as that of the soybean oil treatment group. Both soybean oil and lard led to the exposure of hydrophobic groups on the side chain of proteins in surimi gels. These results suggest that the addition of oil changes protein structure and microenvironment in surimi, which in turn affects the physicochemical properties of surimi gels. The surimi gel with 8% lard has better properties.

The aerobic oxidation of C(sp3)–H bonds is an important issue in organic synthesis, and hydrogen atom transfer (HAT) is an effective process to initiate the oxidation reaction. Here, we demonstrate an innovative strategy for the oxidation of C(sp3)–H bonds based on γ-valerolactone, which can be produced from biomass. This reaction system promotes the aerobic oxidation of various benzylic and allylic C(sp3)–H bonds and alcohols. Excellent chemoselectivity for 1-isochromanone was achieved with the assistance of Ni2Al-layered double hydroxide by increasing the difference in bond dissociation energy between the 1- and 4-C–H bonds of isochroman. The excellent application potential of the reaction system has been demonstrated via the synthesis of pharmaceutical molecules, modification of steroidal substrates, scaled-up oxidation experiments, and the ready availability of γ-valerolactone from biomass. This work also reports on a new carbon-centered radical for the activation of C(sp3)–H bonds. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants in the atmosphere that have drawn intense attention due to their carcinogenicity and mutagenicity. In this work, 1424 air samples were collected between January 2016 and December 2021 in three areas of Shenzhen, China to determine the concentrations of PM2.5 and PAHs and their spatiotemporal variation. Human health risks due to the daily intake and uptake of PAHs and the resulting incremental lifetime cancer risk (ILCR) were also evaluated. PAHs were detected frequently in the samples at concentrations between 0.28 and 32.7 ng/m3 (median: 1.04 ng/m3). PM2.5 and PAH concentrations decreased from 2016 to 2021, and the Yantian area had lower median concentrations of PM2.5 (23.0 μg/m3) and PAHs (0.02 ng/m3) than the Longgang and Nanshan areas. The concentrations of PM2.5 and PAHs were significantly higher in winter than in summer. Analysis of diagnostic ratios indicated that petroleum combustion was the dominant source of airborne PAHs in Shenzhen. The estimated daily intake (EDI) and uptake (EDU) of PAHs by local residents decreased gradually with increasing age, indicating that infants are at particular risk of PAH exposure. However, the incremental lifetime cancer risks (ILCRs) were below the threshold value of 10–6, indicating that inhalation exposure to PAHs posed a negligible carcinogenic risk to Shenzhen residents. While promising, these results may underestimate actual PAH exposure levels, so further analysis of health risks due to PAHs in Shenzhen is needed. [ABSTRACT FROM AUTHOR]

BACKGROUND: Nano starch‐lutein (NS‐L) can be used in three‐dimensional (3D) printed functional surimi. However, the lutein release and printing effect are not ideal. The purpose of this study was to facilitate the function and printing properties of surimi by adding the combination of calcium ion (Ca2+) and NS‐L. RESULTS: Printing properties, lutein release and antioxidation of printed Ca2+‐NS‐L‐surimi were determined. The NS‐L‐surimi with 20 mM kg−1 Ca2+ had the best printing effects (fine accuracy, 99 ± 1%). Compared to NS‐L‐surimi, the structure became denser after adding Ca2+, the gel strength, hardness, elasticity, yield stress (τ), water holding capacity of Ca2+‐NS‐L‐surimi increased by about 17 ± 4%, 3 ± 1%, 9 ± 2%, 20 ± 4%, 40 ± 5% respectively. These enhanced mechanical strength and self‐supporting ability to resist binding deformation and improve printing accuracy. Moreover, salt dissolution and increased hydrophobic force by Ca2+ stimulated protein stretching and aggregation, leading to enhancement of gel formation. Decreased printing effects of NS‐L‐surimi with excessive Ca2+ (> 20 mM kg−1) caused by excessive gel strength and τ, leading to strong extrusion force and low extrudability. Additionally, Ca2+‐NS‐L‐surimi had higher digestibility and lutein release rate (increased from 55 ± 2% to 73 ± 3%), because Ca2+ made NS‐L‐surimi structure porous, which promoted contact of enzyme‐protein. Furthermore, weakened ionic bonds reduced electron binding bondage that combined with released lutein to provide more electrons for enhancing antioxidation. CONCLUSION: Collectively, 20 mM kg−1 Ca2+ could better promote printing process and function exertion of NS‐L‐surimi, facilitating the application of 3D printed functional surimi. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]