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In this paper, the characteristics of a squall line that occurred in central and northern Zhejiang on 21 July 2022 are analyzed by using S-band dual-polarization radar, X-band phased array radar data, wind retrieval, lightning location and ERA5 reanalysis data. The results show that: The squall line affected the area for up to 6 hours, causing large-scale winds of 8-10 levels along the way. The pressure surge ahead of the strong winds and precipitation at the extremely strong wind station served as a precursor to extreme winds. The squall line occurred under the control of the subtropical high. The dry and cold air at the bottom of the high-level cold vortex invaded, with the high-energy and high humidity in the low-level forming an unstable layer structure, which provided favourable environmental conditions for the generation and maintenance of the squall line. The observation of the S-band dual polarisation radar showed that the evolution of squall lines went through processes such as initiation, merging, growth, maturity, and disappearance. The initial convection was formed in the mesoscale convergence lines in the northwest and east of Hangzhou. Strong storms in the northwest of Hangzhou moved faster than those in the east, leading to the rapid merging and development of the two into squall lines. After the squall line entered the south bank of the Hangzhou Bay, the storm outflow overlapped with the mesoscale convergence centre on the south bank of the Hangzhou Bay, leading to the rapid development of the squall line to its mature stage. In addition, the growth of vertical wind shear was also conducive to the rapid development of the squall line. Strong winds often occurred in areas with dense cloud flashes. The X-band phased array radar could finely detect the vertical structure of strong cells before and after extreme winds occurred. The development of ZDR and KDP columns in mature strong cells represented storm intensification, and the rapid decline of the echo centroid could indicate surface winds. The falling and dragging of precipitation particles intensified the sinking motion, which further enhanced the strong winds. The configuration of inclined upward and downward airflow in strong squall lines ensured that the falling of precipitation particles did not affect the upward airflow, which was beneficial for the development and maintenance of storms. The oblique sinking airflow met the near-surface environmental wind, triggering the development of frontal convection, which was conducive to the propagation of squall lines downstream.

Background: Ischemic stroke (IS) is a highly prevalent type of stroke with very high rates of disability and death. As the regulatory role of circular RNAs (circRNAs) in various diseases has been revealed, we constructed a stroke cell model to analyze the action mechanism of hsa_circ_0005548 in IS. Methods: The abundance of hsa_circ_0005548, microRNA-362-3p (miR-362-3p) and E26 transformation specific-1 (ETS-1) were measured by real-time quantitative polymerase chain reaction (RT-qPCR) or western blot. We constructed an IS cell model in vitro by oxygen-glucose deprivation/reperfusion (OGD/R) treatment and analyzed cell proliferation, apoptosis and inflammatory response through the use of Cell Counting Kit-8 (CCK8), 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry and Enzyme-linked immunosorbent assay (ELISA), respectively. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were employed for the analysis of the relationship between miR-362-3p and hsa_circ_0005548 or ETS1. Results: The higher abundance of hsa_circ_0005548 and ETS-1 and lower level of miR-362-3p were observed in human brain microvascular endothelial immortalized (HBMEC-IM) cells under OGD/R. Hsa_circ_0005548 downregulation mitigated OGD/R-induced HBMEC-IM cell injury. Mechanistically, hsa_circ_0005548 targeted miR-362-3p. MiR-362-3p knockdown reversed the effect of hsa_circ_0005548 silencing on OGD/R-induced HBMEC-IM cell injury. ETS1 was validated as a direct target of miR-362-3p, and miR-362-3p attenuated OGD/R-induced HBMEC-IM cell injury by ETS1. Moreover, hsa_circ_0005548 modulated ETS1 via miR-362-3p. Conclusion: Hsa_circ_0005548 knockdown repairs OGD/R-induced HBMEC-IM cell damage via miR-362-3p/ETS1 axis. [ABSTRACT FROM AUTHOR]

A number of long non-coding RNAs (lncRNAs) have been identified to play an important role in the initiation and progression of glioma, including the stemness, survival, apoptosis, invasion, and drug resistance. However, the complex regulatory mechanisms of lncRNAs have not been well understood in glioma. Emerging evidence has confirmed that lncRNAs may act as a competing endogenous RNA (ceRNA) or a molecular sponge in modulating microRNAs (miRNAs), and the miRNAs negatively regulate target mRNA expression through complementarity binding to the 3'-untranslated region (3'UTR) of their target mRNAs. These interactions constitute complex signaling pathways in glioma, such as the lncRNAs/miRNAs/Wnt/β-catenin pathway, the lncRNAs/miRNAs/PI3K/AKT/mTOR pathway, the lncRNAs/miRNAs/Notch pathway, the lncRNAs-miRNAs/MAPK kinase pathway, and the lncRNAs/miRNAs/NF-κB pathway. In this review, the underlying roles and molecular mechanisms of the lncRNAs and miRNAs pathway regulation network in glioma were summarized for a better understanding of tumorigenesis and pathogenesis of glioma.