RESUMEN
BACKGROUND: Selenium is a mineral that showed both pro- and anti-oxidant activities in various disease models. In this study, we evaluated the anti-tumor effect of selenium against 1,2-dimethylhydrazine (DMH)-induced colorectal cancer in BALB/C mice and its effect on apoptosis and angiogenesis. METHODS: Colorectal cancer was induced by subcutaneous injection of DMH (20 mg/kg body weight) in BALB/C mice once weekly for 20 weeks. Selenium (200 mg/L) was given to DMH plus selenium-treated group in the drinking water for the next 3 months. RESULTS: The DMH plus selenium-treated group exhibited significantly lower expression of cloned caudal-type homebox gene -2 (CDX-2) and vascular endothelial growth factor (VEGF) but higher caspase-3 expression level at p < 0.001 compared to the DMH-treated group. Moreover, a decrease in the reduced glutathione content and glutathione peroxidase activity but an increase in the malondialdehyde content were observed at p < 0.001. Both macroscopic and microscopic examination of the colorectal tissues confirmed the results. CONCLUSION: The anti-tumor effect of selenium against an induced colorectal cancer in mice is attributed to its pro-oxidant, anti-angiogenic and apoptotic effects.
RESUMEN
Investment in Africa over the past year with regards to SARS-CoV-2 genotyping has led to a massive increase in the number of sequences, exceeding 100,000 genomes generated to track the pandemic on the continent. Our results show an increase in the number of African countries able to sequence within their own borders, coupled with a decrease in sequencing turnaround time. Findings from this genomic surveillance underscores the heterogeneous nature of the pandemic but we observe repeated dissemination of SARS-CoV-2 variants within the continent. Sustained investment for genomic surveillance in Africa is needed as the virus continues to evolve, particularly in the low vaccination landscape. These investments are very crucial for preparedness and response for future pathogen outbreaks. One-Sentence SummaryExpanding Africa SARS-CoV-2 sequencing capacity in a fast evolving pandemic.