Increased levels of adhesion molecules or metalloproteinases (MMPs) may indicate endothelial dysfunction. Exercise mobilizes circulating angiogenic cells (CACs) from bone marrow in healthy subjects, improving vascular function. However, it is unclear whether this mechanism is preserved in the early stages of metabolic syndrome (early MetS). We aimed to evaluate the acute effects of exercise on adhesion molecules, angiogenic factors, MMPs, and CACs in early MetS. Fifteen subjects with early MetS and nine healthy controls underwent an exercise session and a nonexercise session, randomly. Adhesion molecules, angiogenic factors, CACs, and MMPs were evaluated before and after exercise or nonexercise sessions. At baseline, levels of sE-selectin, sICAM-1, and MMP-9 were higher in early MetS than in controls (P≤0.03). After exercise, sE-selectin, sICAM-1, and MMP-9 levels were still higher in early MetS (P<0.05). Subjects with early MetS presented less CACs (P=0.02) and higher MMP-9 activity (P≤0.04), while healthy controls presented higher MMP-2 activity after exercise. There was no difference between moments in nonexercise session (P>0.05). In conclusion, subjects with early MetS already presented impaired endothelial function at rest along with a decrease in CACs and an increase in MMP-9 activity in response to exercise.

Knowledge of viral load is essential for formulating strategies for antiviral treatment, vaccination, and epidemiological control of COVID-19. Moreover, patients identification with high viral load could also be useful to understand risk factors such as age, comorbidities, severity of symptoms and hypoxia to decide the need for hospitalization. Several studies are evaluating the importance of analyzing viral load in different types of samples, clinical outcomes and viral transmission pathways. However, in a great number of emerging studies cycle threshold (Ct) values by itself is often used as a viral load indicator, which may be a mistake. In this study, we compared tracheal aspirate with nasopharyngeal samples obtained from critically ill COVID-19 patients and demonstrate how the raw Ct could lead to misinterpretation of results. Further, we analyzed nasopharyngeal swabs positive samples and propose a method to reduce evaluation error that could occur from using raw Ct. Based on these findings, we show the impact that normalization of Ct values has on interpretation of viral load data from different biological samples from patients with COVID-19, transmission and lastly in relations with clinical outcomes. Importance: In a pandemic, prevention of disease transmission is key. Reliable data for profiles of viral load are needed and important to guide antiviral treatment, infection control and vaccination. The differential expression of SARS-CoV-2 viral RNA among patient groups is a current topic of interest and viral load has been associated with a diversity of outcomes. However, in a great number of emerging studies cycle threshold (Ct) values by itself is often used as a viral load indicator, which may be a mistake. In this study, we compared tracheal aspirate with nasopharyngeal samples obtained from critically ill COVID-19 patients and demonstrate how the raw Ct could lead to misinterpretation of results. Based on these findings, we show the impact that normalization of Ct values has on interpretation of viral load data from different biological samples from patients with COVID-19, transmission and lastly in relations with clinical outcomes.