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Background: After the adjustment of COVID-19 epidemic policy, mainland China experienced two consecutive waves of Omicron variants within a seven-month period. In Guangzhou city, as one of the most populous regions, the viral infection characteristics, molecular epidemiology, and the dynamic of population immunity are still elusive. Methods: We launched a prospective cohort study in the Guangdong Provincial CDC from December 2022 to July 2023. Fifty participants who received the same vaccination regimen and had no previous infection were recruited. Results: 90% of individuals were infected with Omicron BA.5* variants within three weeks in the first wave. Thirteen cases (28.26%) experienced infection with XBB.1* variants, occurring from 14 weeks to 21 weeks after the first wave. BA.5* infections exhibited higher viral loads in nasopharyngeal sites compared to oropharyngeal sites. Compared to BA.5* infections, the XBB.1* infections had significantly milder clinical symptoms, lower viral loads, and shorter durations of virus positivity. The infection with the BA.5* variant elicited varying levels of neutralizing antibodies against XBB.1* among different individuals, even with similar levels of BA.5* antibodies. The level of neutralizing antibodies specific to XBB.1* determined the risk of reinfection. Conclusions: The rapid large-scale infections of the Omicron variants have quickly established herd immunity among the population in mainland China. In the future of the COVID-19 epidemic, a lower infection rate but a longer duration can be expected. Given the large population size and ongoing diversified herd immunity, it remains crucial to closely monitor the molecular epidemiology of SARS-CoV-2 for the emergence of new variants of concern in this region. Additionally, the timely evaluation of the immune status across different age groups is essential for informing future vaccination strategies and intervention policies. [ABSTRACT FROM AUTHOR]

We report a ligand‐to‐metal charge‐transfer (LMCT) process that used ferric (III) chloride as efficient chlorination reagent to mediate the vicinal dichlorination of alkenes. Under 420 nm LED light, the easily available and safe ferric (III) chloride could facilitate various alkenes to transform as 1,2‐dichloride compounds with good to excellent yields (19 examples). The strategy showed a more economic protocol than CuCl2, and provided a significant reference for the light‐Induced dichlorination in industrial catalysis. [ABSTRACT FROM AUTHOR]

Green waste is gradually increasing as national forest city construction is promoted. Using green waste compost (GWC) products as seedling substrates is an effective way to achieve ecological sustainability. Nevertheless, some GWC are not always suitable for directly serving as seedling substrates due to their inappropriate physicochemical properties (i.e. undesirable porosity, high pH, high salinity, lower nutrient elements, etc.). This research aimed to evaluate how the addition of rice husk ash (RHA; 0, 2.5, 5%) and coco coir (CC; 0, 10, 20%) affected the physicochemical properties of GWC as well as its usage as a seedling substrate for Cucurbitaceae plants. The GWC was optimized by 2.5% RHA and 10% CC as the seedling substrate had the best physical and chemical properties (i.e. bulk density, porosity, water-holding capacity, pH, conductivity, and nutrient content). And the seedlings of cucumber and watermelon grew best under this seedling substrate in terms of germination energy and total biomass. Compared to GWC without RHA or CC amendments, GWC modified with 2.5% RHA and 10% CC enhanced the germination energy and total biomass of cucumber seedlings by 252% and 60%, respectively, and the germination energy and total biomass of watermelon seedlings increased by 61% and 67%, respectively. In consequence, the GWC that had been modified by 2.5% RHA and 10% CC was an excellent seedling substrate for Cucurbitaceae plants. [ABSTRACT FROM AUTHOR]

Abstract Background Brassinosteroids (BRs) play a crucial role in plant vegetative growth and reproductive development. The transcription factors BZR1 and BES1/BZR2 are well characterized as downstream regulators of the BR signaling pathway in Arabidopsis and rice. Soybean contains four BZR1-like proteins (GmBZLs), and it was reported that GmBZL2 plays a conserved role in BR signaling regulation. However, the roles of other GmBZLs have not been thoroughly studied, and the targets of GmBZLs in soybean remain unclear. Results In this study, we first characterized GmBZL3 in soybean from gene expression patterns, conserved domains in coding sequences, and genomic replication times of four GmBZL orthologous. The results indicated that GmBZL3 might play conserved roles during soybean development. The overexpression of GmBZL3 P219L in the Arabidopsis BR-insensitive mutant bri1–5 partially rescued the phenotypic defects including BR-insensitivity, which provides further evidence that GmBZL3 functions are conserved between soybean and the homologous Arabidopsis genes. In addition, the identification of the GmBZL3 target genes through ChIP-seq technology revealed that BR has broad roles in soybean and regulates multiple pathways, including other hormone signaling, disease-related, and immunity response pathways. Moreover, the BR-regulated GmBZL3 target genes were further identified, and the results demonstrate that GmBZL3 is a major transcription factor responsible for BR-regulated gene expression and soybean growth. A comparison of GmBZL3 and AtBZR1/BES1 targets demonstrated that GmBZL3 might play conserved as well as specific roles in the soybean BR signaling network. Finally, the identification of two natural soybean varieties of the GmBZL3 mutantion by SNP analysis could facilitate the understanding of gene function during soybean development in the future. Conclusions We illustrate here that GmBZL3 orchestrates a genome-wide transcriptional response that underlies BR-mediated soybean early vegetative growth, and our results support that BRs play crucial regulatory roles in soybean morphology and gene expression levels.

Objective: Endometriosis is a common gynecological disease with an enigmatic pathogenesis. Recent studies suggest that the behavior of normal endometrial stromal cells can dramatically change under hypoxic conditions, which effectively turns them into endometriotic stromal cells. Because menstrual debris is not only hypoxic but may also contain platelet aggregates, at present, we aimed to approve that activated platelets could induce hypoxia-inducible factor-1α (HIF-1α) expression in endometrial stromal cells, signaling the presence of hypoxia. Methods: We evaluated the gene and protein expression levels of HIF-1α and its target gene erythropoietin (EPO) in both human endometriotic stromal cells (HESCs) and a human endometrial stromal cell line (ESCL) cocultured with or without activated platelets for 48 h. Results: We found that the gene and protein expression levels of HIF-1α and EPO in both HESC and ESCL were significantly increased after coculture with activated platelets. We also found that neutralization of transforming growth factor-β1 completely abolishes this induction. Conclusions: Platelets can induce a hypoxic state in endometrial and endometriotic stromal cells, resulting in increased angiogenesis, as well as enhanced survival and proliferation. In conjunction with other roles that platelets play in the development of endometriosis, our findings further highlight the important roles of platelets in the development and initiation of endometriosis, shedding new light into the etiology of endometriosis.

As an important enzyme involved in the marine carbon cycle, alginate lyase has received extensive attention because of its excellent degradation ability on brown algae, which is widely utilized for alginate oligosaccharide preparation or bioethanol production. In comparison with endo-type alginate lyases (PL-5, PL-7, and PL-18 families), limited studies have focused on PL-17 family alginate lyases, especially for those with special characteristics. In this study, a novel PL-17 family alginate lyase, Aly23, was identified and cloned from the marine bacterium Pseudoalteromonas carrageenovora ASY5. Aly23 exhibited maximum activity at 35 °C and retained 48.93% of its highest activity at 4 °C, representing an excellent cold-adaptation property. Comparative molecular dynamics analysis was implemented to explore the structural basis for the cold-adaptation property of Aly23. Aly23 had a high substrate preference for poly β-D-mannuronate and exhibited both endolytic and exolytic activities; its hydrolysis reaction mainly produced monosaccharides, disaccharides, and trisaccharides. Furthermore, the enzymatic hydrolyzed oligosaccharides displayed good antioxidant activities to reduce ferric and scavenge radicals, such as hydroxyl, ABTS+, and DPPH. Our work demonstrated that Aly23 is a promising cold-adapted biocatalyst for the preparation of natural antioxidants from brown algae.