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Purpose: Recently, the SARS-CoV-2 Omicron variant was identified as responsible for a novel wave of COVID-19 worldwide. We perform a retrospective study to identify potential risk factors contributing to radiological progression in the COVID-19 patients due to the Omicron variant infection. These findings would provide guiding information for making clinical decisions that could improve the Omicron infection prognosis and reduce disease-related death. Methods: This is a retrospective cohort study from a single center in China. According to the radiological change within admissive one week, enrolled cases were divided into two groups: the progressive (1w-PD) and the stable or improved disease (1w-non-PD). Separate analyses were performed on patients stratified into subgroups using the Mann–Whitney U-test, the Fisher exact test, or the Chi-squared test and a multivariable logistic regression analysis. Results: Both the 1w-non-PD and 1w-PD cohorts displayed comparable asymptomatic infection, have similar underlying disease, impairment in respiratory function, coagulation dysfunction, tissue injury, SARS-CoV-2 viral load, and disease severity. However, the 1w-PD cohort was more inclined to cluster in populations presented with age between 41 and 65, higher CURB-65 scores, undetectable SARS-CoV-2 IgG, and lung affection. Based on the multiple logistic regression analysis, complicated bilateral and ground-glass opacities (GGOs) like pneumonia at admission were independent risk factors to radiological progression within admissive one week. Conclusion: This study provided preliminary data regarding disease progression in Omicron-infected patients that indicated the development of pneumonia in the context of Omicron infection was worthy of potential risk factors. [ABSTRACT FROM AUTHOR]

Teramethylpyrazine (TMP) is a pyrazine alkaloid with a variety of pharmacological effects and widely used in clinical practice. In this study,Monascusstrain M-3 with high TMP and low citrinin productions was screened from red yeast rice collected from different areas of Fujian province in China.Monascusstrain M-3 was further identified through molecular biological methods based on the sequencing of different gene regions. Results showed that primer set of β-tubulin-F/β-tubulin-R targeting the β-tubulin gene was more suitable for the identification ofMonascusstrain M-3. Based on comparative analysis of the results obtained by different primer sets,Monacusstrain M-3 was finally identified asMonascus purpureus. Then, the composition of culture medium and liquid state fermentation conditions ofMonacusstrain M-3 were optimized by single-factor experiment and central composite design of response surface methodology, with the purpose of optimizing the TMP productions. The optimum composition of culture medium and liquid state fermentation conditions are as follows: starch 5.1%, peptone 3.51%, Mg2SO40.1%, NaNO30.2%, KH2PO40.25%, fermentation temperature of 28.23 °C, fermentation time of 9 d, shaker speed of 180 r/min, inoculum size of 7.21% and loading volume of 100 mL/250 mL triangular flask. Under the optimum composition of culture medium and liquid state fermentation conditions, the TMP production ofMonacusstrain M-3 can reach 13.49 µg/mL. This study is expected to provide a new approach of TMP production through biosynthesis byMonascusstrain, and promote the further development of functional foods or medicines fromMonascusfermentation products. [ABSTRACT FROM AUTHOR]

Following the first experimental realization of graphene, other ultrathin materials with unprecedented electronic properties have been explored, with particular attention given to the heavy group-IV elements Si, Ge and Sn. Two-dimensional buckled Si-based silicene has been recently realized by molecular beam epitaxy growth, whereas Ge-based germanene was obtained by molecular beam epitaxy and mechanical exfoliation. However, the synthesis of Sn-based stanene has proved challenging so far. Here, we report the successful fabrication of 2D stanene by molecular beam epitaxy, confirmed by atomic and electronic characterization using scanning tunnelling microscopy and angle-resolved photoemission spectroscopy, in combination with first-principles calculations. The synthesis of stanene and its derivatives will stimulate further experimental investigation of their theoretically predicted properties, such as a 2D topological insulating behaviour with a very large bandgap, and the capability to support enhanced thermoelectric performance, topological superconductivity and the near-room-temperature quantum anomalous Hall effect. [ABSTRACT FROM AUTHOR]