Neutrophil-Lymphocyte Ratio as a Predictor of the Risk of Death in Severe Cases of COVID-19.

BACKGROUND: Identifying clinical characteristics and risk factors, comorbid conditions, and complications arising from SARS-CoV-2 infection is important to predict the progression to more severe forms of the disease among hospitalized individuals to enable timely intervention and to prevent fatal outcomes. The aim of the study is to assess the possible role of the neutrophil/lymphocyte ratio (NLR) as a biomarker of the risk of death in patients with comorbidities hospitalized with COVID-19 in a tertiary hospital in southern Brazil. METHODS: This is a prospective cohort study on patients with SARS-CoV-2 infection admitted to a hospital in the metropolitan region of Porto Alegre from September 2020 to March 2022. RESULTS: The sample consisted of 185 patients with associated comorbidities, namely, hypertension, diabetes mellitus, obesity, cardiovascular, pulmonary, and renal diseases, hospitalized with COVID-19. Of these, 78 died and 107 were discharged alive. The mean age was 66.5 years for the group that died and 60.1 years for the group discharged. Statistical analysis revealed that a difference greater than or equal to 1.55 in the NLR, from hospitalization to the 5th day, was associated with a relative risk of death greater than 2. CONCLUSIONS: Measuring a simple inflammatory marker such as NLR may improve the risk stratification of comorbid patients with COVID-19 and can be considered a useful biomarker.

Syzygium cumini is more effective in preventing the increase of erythrocytic ADA activity than phenolic compounds under hyperglycemic conditions in vitro

Syzygium cumini (S. cumini) is a plant known for its antidiabetic properties. The aim of this study was to evaluate the effect of Sc aqueous leaf extract (ASc) on adenosine deaminase (ADA) activity in erythrocytes (RBCs) exposed to high glucose concentrations (30 mM) in vitro. We also investigated the effects of the main phenolic compounds found in ASc (gallic acid, rutin, and chlorogenic acid) and the effects of insulin, caffeine, and dipyridamole, which are substances involved in the adenosine metabolism, on ADA activity in vitro. Blood samples were obtained from healthy volunteers and a suspension of RBCs was used for the determination of ADA activity. The results showed that: (1) the effect of ASc on ADA activity was more significant than the combination of phenolic compounds; (2) insulin, caffeine, or dipyridamole prevented high glucose increase of ADA activity at doses as low as 50 μU/mL, 25 μM, and 1 μM, respectively; (3) the inhibitory effect caused by ASc on erythrocyte ADA activity remained practically the same after the combination of the extract with insulin or caffeine; (4) when RBCs were exposed to ASc plus dipyridamole, this chemical attenuated the effect of ASc on ADA activity, suggesting an antagonism or a competition with ASc by the same site of action. Therefore, ASc was more effective in preventing the increase in ADA activity than phenolic compounds, suggesting that ASc may collaborate to improve endothelial dysfunction, antioxidant, anti-inflammatory, and antithrombotic properties of adenosine by affecting its metabolism. The results of this study help to provide evidence of the empirically supported benefits of the use of S. cumini in diabetes