[Analysis of the whole genome traceability and transmission path simulation experiment of the local cluster COVID-19 epidemic].

Objective: To trace and characterize the whole genome of SARS-CoV-2 of confirmed cases in the outbreak of COVID-19 on July 31, 2021 in Henan Province. Method: Genome-wide sequencing and comparative analysis were performed on positive nucleic acid samples of SARS-CoV-2 from 167 local cases related to the epidemic on July 31, 2021, to analyze the consistency and evolution of the whole genome sequence of virus. Results: Through high-throughput sequencing, a total of 106 cases of SARS-CoV-2 whole genome sequences were obtained. The results of genome analysis showed that the whole genome sequences of 106 cases belonged to the VOC/Delta variant strain (B.1.617.2 clade), and the whole genome sequences of 106 cases were shared with the genomes of 3 imported cases from Myanmar admitted to a hospital in Zhengzhou. On the basis of 45 nucleotide sites, 1-5 nucleotide variation sites were added, and the genome sequence was highly homologous. Conclusion: Combined with the comprehensive analysis of viral genomics, transmission path simulation experiments and epidemiology, it is determined that the local new epidemic in Henan Province is caused by imported cases in the nosocomial area, and the spillover has caused localized infection in the community. At the same time, it spills over to some provincial cities and results in localized clustered epidemics.

RNA Transfection with Hypoxia Inducible Factor-1alpha

Introduction: Ischemic necrosis of dermal flaps is a devastating complication of reconstructive surgery. The increasing prevalence of diabetes, obesity, and an aging population adds to this concern. Hypoxia-inducible factor-1alpha (HIF-1alpha), a master regulator of the adaptive response to hypoxia, controls the expression of angiogenic growth factors. The development of biologically active, gene-specific mRNAs, especially in COVID-19 vaccines, has shown the ability for intracellular protein expression. We sought to express HIF-1alpha through mRNA transfection and determined its biological activity by measuring the upregulation of selected downstream targets. Method(s): 5'-methyl-capped poly-A tailed mRNA was generated using T7 RNA polymerase and verified by gel electrophoresis. Predominant and variant HIF-1alpha mRNA were transfected into primary human dermal fibroblasts via Lipofectamine in triplicate, and RNA levels were assessed using RT-qPCR. All gene expression levels were normalized to beta-actin expression levels Results: At one day after transfection, the levels of HIF-1alpha transcript were significantly higher in the cells transfected with predominant (p = 0.0104) and variant (p = 0.0007) HIF-1alpha transcripts relative to the control. Additionally, the expression of HIF-1alpha transcription product genes VEGF (p = 0.0274) and ANG-1 (p = 0.05) were significantly higher in the cells transfected with the HIF-1alpha transcripts than the control. Conclusion(s): Our approach led to the successful transfection of HIF-1alpha mRNA into human fibroblasts, resulting in upregulation of HIF-1alpha downstream angiogenic targets. Thus, the use of biologically active HIF-1alpha mRNA transfection offers a promising approach to inhibit ischemic necrosis.