ABSTRACT
Background: Heme-oxygenase 1 (HO-1) is an intracellular enzyme that is part of a broad anti-inflammatory and antioxidative pathway, in which it metabolizes heme delivered to cells by hemopexin. Although initial suggestions of a direct action of SARS-CoV- 2 on hemoglobin or heme have already been refuted, HO-1 activation is recognized as part of the host response and as a potential therapeutic target in several diseases involving thrombosis and inflammation. Aim(s): To evaluate circulating levels of hemopexin, heme and HO-1 in COVID-19, and their association with clinical and laboratory markers of disease severity. Method(s): Thirty consecutive patients with confirmed COVID-19 admitted due to hypoxemia were enrolled, along with 30 age and sex-matched healthy volunteers. HO-1 and hemopexin were measured by ELISA, and heme was measured by a colorimetric method. Samples were obtained on admission. Coagulation and inflammatory biomarkers were measured using commercional kits. Result(s): HO-1 levels were higher in patients compared to healthy volunteers, and a trend towards higher hemopexin levels was also observed. In contrast heme levels were similar in patients and controls. A significant decrease in HO-1 levels was observed at the 4th day of hospital stay, and the magnitude of this decrease (DELTAHO-1) was correlated with the number of days in intensive care. Moreover, admission HO-1 levels were correlated with several biomarkers of hemostasis and fibrinolysis activation. Conclusion(s): Upregulation of HO-1 is observed in COVID-19. HO-1 levels on admission were associated with markers of coagulation and fibrinolysis activation. Persistance of high HO-1 levels during admssion was associated with longer ICU stay. (Figure Presented).
ABSTRACT
Background: Podoplanin (PDPN) and CLEC-2 have been involved in the pathogenesis of thrombosis in inflammatory and neoplastic diseases. In addition, prior studies suggested that PDPN can be protective animal models of sepsis, as well as in models of acute lung injury. Aim(s): To measure circulating levels of PDPN and CLEC-2 in COVID-19 and explore their relationship with clinical and laboratory markers of disease severity. Method(s): Thirty consecutive patients with COVID-19 admitted due to hypoxemia and 30 age and sex-matched controls were enrolled. PDPN and CLEC-2 levels were measured by commercial ELISA kits on admission, and at day+4 (PDPN). Biomarkers of hemostasis were measured using commercial kits and clinical data were obtained from medical records. Result(s): CLEC-2 levels were similar between patients and controls, while lower PDPN levels were observed in patients when compared to healthy volunteers and these results were confirmed using two different ELISA kits. In addition, patients requiring intensive care presented lower PDPN levels compared to ward patients. PDPN levels were inversely correlated with biomarkers of coagulation and fibrinolysis activation. Conclusion(s): Circulating levels of PDPN were reduced in patients with COVID-19, and negatively correlated with markers of coagulation and fibrinolysis activation, as well as with and ICU need. Co-expression of ACE2 and PDPN in alveolar epithelial cells could underlie these findings. Additional studies are warranted to confirm these observations in independent populations and to explore their potential mechanistic implications. (Figure Presented).
ABSTRACT
The COVID-19 pandemic resulted in stay-at-home policies and other social distancing behaviors in the United States in spring of 2020. This paper examines the impact that these actions had on emissions and expected health effects through reduced personal vehicle travel and electricity consumption. Using daily cell phone mobility data for each U.S. county, we find that vehicle travel dropped about 40% by mid-April across the nation. States that imposed stay-at-home policies before March 28 decreased travel slightly more than other states, but travel in all states decreased significantly. Using data on hourly electricity consumption by electricity region (e.g., balancing authority), we find that electricity consumption fell about 6% on average by mid-April with substantial heterogeneity. Given these decreases in travel and electricity use, we estimate the county-level expected improvements in air quality, and, therefore, expected declines in mortality. Overall, we estimate that, for a month of social distancing, the expected premature deaths due to air pollution from personal vehicle travel and electricity consumption declined by approximately 360 deaths, or about 25% of the baseline 1500 deaths. In addition, we estimate that CO2 emissions from these sources fell by 46 million metric tons (a reduction of approximately 19%) over the same time frame. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.