ABSTRACT
Background: to date, more than 243 million COVID-19 cases have been diagnosed globally, with 4.94 million deaths, 489.000 new cases and 8.474 deaths per day. In Italy there are currently 4.73 million cases and 132.000 deaths. It is well known that the entry of the SARS- CoV-2 virus into cells is mediated by the binding between the virus Spike-glycoprotein (S) and the membrane ACE2-receptor (ACE2-R). When SARS-CoV-2 binds to ACE2-R, with subsequent membrane fusion and virus entry into the cell, a down-regulation of these receptors occurs. ACE2 -R downregulation plays a crucial role in the pulmonary and systemic inflammatory response. A serious clinical course appears to be associated with some factors such as age, previous pathologies and comorbidities. However, also a dysregulation of the RAA system linked to a different expression of ACE-2 R and TMPRSS2 gene polymorphisms and different serum levels of soluble ACE2 (sACE2), could be associated with abnormal inflammatory and immune response to SARS-CoV-2 infection. Aim of the Study: we aimed to verify whether there is an association between the clinical course of COVID-19 patients (pts) and the presence of more frequent ACE2 and TMPRSS2 single-nucleotide polymorphisms (SNPs) and if sACE2 levels are related to specific ACE2 and TMPRSS2 polymorphic variants. Method(s): we consecutively enrolled subjects with previous documented SARS-CoV-2 infection and divided our sample into three groups: pts with asymptomatic course;pts with symptomatic course but without the need for hospitalization for COVID-19;pts with severe symptomatic course requiring hospitalization in intensive care unit. Data about age, clinical course, comorbidities, and therapies were collected. Blood samples were taken for the genetic analysis of the most frequent SNPs of the ACE2-R and TMPRSS2 detected in Italian population, in particular genotypic variants TTand CC of ACE2 SNPs 1 and 5 (rate of 5% and 14% respectively) and genotypic variants TTand CC of TMPRSS2 SNPs 2 and 3 (rate of 50% and 30% respective). Result(s): among 178 pts enrolled up to March 2022, we have so far analyzed the genetic polymorphisms of 74 pts.;21 (28%) were hospitalized for COVID-19, 38 (51%) had symptomatic course without hospitalization and 15 (21%) were completely pauci-asymptomatics. Serum concentrations of sACE2 and distribution of polymorphic variants in the three groups are summarized in Table 1. We found that sACE2 levels were higher in genotypic variant CC of SNP 1 of TMPRSS2 gene (Table 2). Considering that a high concentration of sACE2 outlines a proinflammatory condition, it could be hypothesized that the CC genotype may be a predisposing condition to the cytokine storm of COVID-19. Perspective(s): Genetic analysis of ACE2 and TMPRSS2 SNPs will help to clarify the relationship between these polymorphic variant, sACE2 levels, risk of SARS-CoV2 infection and severity of clinical presentation of COVID-19 in patients with or without CV diseases.
ABSTRACT
Background: It is well known that the entry of the SARS- CoV-2 virus into cells is mediated by the binding between the virus Spike-glycoprotein (S) and the membrane ACE2-receptor (ACE2R). When SARS-CoV-2 binds to ACE2R, with subsequent membrane fusion and virus entry into the cell, a down-regulation of these receptors occurs. ACE2R downregulation plays a crucial role in the pulmonary and systemic inflammatory response. Also ACE2 deficiency is thought to play an important role in the pathogenesis of SARS-CoV-2 infection. The down-regulation of ACE2 induced by viral infection could be particularly harmful in subjects with pre-existing ACE2 deficiency, for example due to advanced age, the presence of DM, arterial hypertension or pre-existing heart disease, including HF. Literature data suggest an association between the patient's age and comorbidities and a greater risk of severe clinical course and with a worse prognosis. However, serious clinical pictures requiring hospitalization or leading to death have also been observed in young subjects or subjects without comorbidities. Aim of the Study: we aimed to identify predicting factors of a higher risk in terms of severity of the clinical course and worse prognosis in the population of the Brescia area, affected by a large number of cases in the first period of COVID-19 outbreak. In particular, we aimed to verify whether there is correlation between levels of serum ACE2 (sACE2) and the risk of SARS-CoV-2 infection, as well as between sACE2 and the different severity of the clinical manifestations of COVID-19 in patients with and without CV diseases. Method(s): we consecutively enrolled subjects with previous documented SARS-CoV-2 infection and divided our sample into three groups: pts with asymptomatic course;pts with symptomatic course but without the need for hospitalization for COVID-19;pts with severe symptomatic course requiring hospitalization in intensive care unit. Blood samples were taken for sACE2 dosage. We compared the concentrations of sACE2 in these groups in relation to the age, clinical course, comorbidities, and ongoing therapies. Result(s): at March 2022, we enrolled 178 pts, 51 (28%) were hospitalized for COVID-19, whereas 78 (44%) had symptomatic course without hospitalization and 49 (28%) were completely pauci-asymptomatic. Only 6 pts (4%) had myocarditis or pericarditis SARS-CoV-2-related. Between hospitalized pts, male sex (67%), older age and higher BMI were most frequent. Moreover, chronic heart failure (20%), a diagnosis of cardiopathy (29%) and AF or atrial flutter (22%) were most frequent (Table 1). Plasma concentrations of sACE2 will be dosed and analyzed in relation to the clinical characteristics of each patient. Perspective(s): ACCEPTstudy will help to clarify the relationship between ACE2 molecule, the risk of SARS-CoV2 infection and the severity of clinical presentation of COVID-19 in pts with or without CV diseases.
ABSTRACT
The outbreak of SARS-CoV-2 pandemic highlighted the worldwide lack of surgical masks and personal protective equipment, which represent the main defense available against respiratory diseases as COVID-19. At the time, masks shortage was dramatic in Italy, the first European country seriously hit by the pandemic: aiming to address the emergency and to support the Italian industrial reconversion to the production of surgical masks, a multidisciplinary team of the University of Bologna organized a laboratory to test surgical masks according to European regulations. The group, driven by the expertise of chemical engineers, microbiologists, and occupational physicians, set-up the test lines to perform all the functional tests required. The laboratory started its activity on late March 2020, and as of the end of December of the same year 435 surgical mask prototypes were tested, with only 42 masks compliant to the European standard. From the analysis of the materials used, as well as of the production methods, it was found that a compliant surgical mask is most likely composed of three layers, a central meltblown filtration layer and two external spunbond comfort layers. An increase in the material thickness (grammage), or in the number of layers, does not improve the filtration efficiency, but leads to poor breathability, indicating that filtration depends not only on pure size exclusion, but other mechanisms are taking place (driven by electrostatic charge). The study critically reviewed the European standard procedures, identifying the weak aspects; among the others, the control of aerosol droplet size during the bacterial filtration test results to be crucial, since it can change the classification of a mask when its performance lies near to the limiting values of 95 or 98%.