The use of the time-to-event index (Tevent) to compare the negative impact of COVID-19 on public health among continents/regions in 2020 and 2021: An observational study.

BACKGROUND: During the COVID-19 pandemic, how to measure the negative impact caused by COVID-19 on public health (ImpactCOV) is an important issue. However, few studies have applied the bibliometric index, taking both infected days (quantity) and impact (damage) into account for evaluating ImpactCOV thus far. This study aims to verify the proposed the time-to-event index (Tevent) that is viable and applicable in comparison with 11 other indicators, apply the Tevent to compare the ImpactCOVs among groups in continents/countries in 2020 and 2021, and develop an online algorithm to compute the Tevent-index and draw the survival analysis. METHODS: We downloaded COVID-19 outbreak data of daily confirmed cases (DCCs) for all countries/regions. The Tevent-index was computed for each country and region. The impactCOVs among continents/countries were compared using the Tevemt indices for groups in 2020 and 2021. Three visualizations (i.e., choropleth maps, forest plot, and time-to-event, a.k.a. survival analysis) were performed. Online algorithms of Tevent as a composite score to denote the ImpactCOV and comparisons of Tevents for groups on Google Maps were programmed. RESULTS: We observed that the top 3 countries affected by COVID-19 in 2020 and 2021 were (India, Brazil, Russia) and (Brazil, India, and the UK), respectively; statistically significant differences in ImpactCOV were found among continents; and an online time-event analysis showed Hubei Province (China) with a Tevent of 100.88 and 6.93, respectively, in 2020 and 2021. CONCLUSION: The Tevent-index is viable and applicable to evaluate ImpactCOV. The time-to-event analysis as a branch of statistics for analyzing the expected duration of time until 1 event occurs is recommended to compare the difference in Tevent between groups in future research, not merely limited to ImpactCOV.

Synthesis, in vitro macrophage response and detoxification of bamboo charcoal beads for purifying blood.

Bamboo charcoal beads (BCBs) were formed by coprecipitating bamboo charcoal particles with chitosan in alkaline solution. The amount of chitosan in the BCBs and their surface properties were measured. When 13-52 mg BCBs were exposed to RAW 264.7 macrophages, the amount of nitric oxide released and the cell viability were close to those of the blank. The amount of cytokine IL-6 secreted by macrophages did not depend on the dose of BCBs but macrophages secreted more TNF-alpha in response to higher doses of BCBs. However, the cytokine levels were relatively low, suggesting the favorable biocompatibility of BCBs. In adsorption experiments, BCBs adsorbed and released bovine serum albumin at particular concentrations, whereas BCBs adsorbed L-phenylalanine without a sign of release. This difference is attributed to the hydrophilicity and the pore size of the BCBs. Finally, the potential of BCBs as biocompatible adsorbents in blood detoxification is considered.