RESUMO
BackgroundAngiotensin converting enzyme (ACE) type 2 is the receptor of SARS-CoV-2 for entry into lungs cells. Because ACE-2 may be modulated by ACE inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs), there is concern that patients treated with ACEIs and ARBs are at higher risk for COVID-19 infection. AimThis study sought to analyze the association of COVID-19 with previous treatment with ACEI and ARB. MethodsWe retrospectively reviewed 684 consecutive patients hospitalized for suspected COVID-19 pneumonia and tested by PCR. Patients were split into 2 groups, whether (group 1, n=484) or not (group 2, n=250) COVID-19 was confirmed. Multivariate adjusted comparisons included a propensity score analysis. ResultsAge was 63.6{+/-}18.7 years, and 302(44%) were female. Hypertension was present in 42.6% and 38.4% patients of group 1 and 2, respectively (P=0.28). A treatment with ARBs (20.7% versus 12.0%, respectively, OR 1.92, 95% confidence interval [1.23-2.98], p=0.004) was more frequent in patients of group 1 than in group 2. No difference was found for treatment with ACEIs (12.7% vs 15.7%, respectively, OR 0.81 [0.52-1.26], p=0.35). Propensity score matched multivariate logistic regression confirmed a significant association between COVID-19 and a previous treatment with ARBs (adjusted OR 2.18 [1.29-3.67], p=0.004). Significant interaction between ARBs and ACEIs for the risk of COVID-19 was observed in patients aged>60, women, and hypertensive patients. ConclusionThis study suggests that ACEIs and ARBs are not similarly associated with the COVID-19. In this retrospective series, patients with COVID-19 pneumonia received more frequently a previous treatment with ARBs, than patients without COVID-19.
RESUMO
Synthesis of functionalized magnetic nanoparticles (NPs) for biomedical applications represents a current challenge. In this paper we present the synthesis and characterization of water-dispersible sugar-coated iron oxide NPs specifically designed as magnetic fluid hyperthermia heat mediators and negative contrast agents for magnetic resonance imaging. In particular, the influence of the inorganic core size was investigated. To this end, iron oxide NPs with average size in the range of 4-35 nm were prepared by thermal decomposition of molecular precursors and then coated with organic ligands bearing a phosphonate group on one side and rhamnose, mannose, or ribose moieties on the other side. In this way a strong anchorage of the organic ligand on the inorganic surface was simply realized by ligand exchange, due to covalent bonding between the Fe(3+) atom and the phosphonate group. These synthesized nanoobjects can be fully dispersed in water forming colloids that are stable over very long periods. Mannose, ribose, and rhamnose were chosen to test the versatility of the method and also because these carbohydrates, in particular rhamnose, which is a substrate of skin lectin, confer targeting properties to the nanosystems. The magnetic, hyperthermal, and relaxometric properties of all the synthesized samples were investigated. Iron oxide NPs of ca. 16-18 nm were found to represent an efficient bifunctional targeting system for theranostic applications, as they have very good transverse relaxivity (three times larger than the best currently available commercial products) and large heat release upon application of radio frequency (RF) electromagnetic radiation with amplitude and frequency close to the human tolerance limit. The results have been rationalized on the basis of the magnetic properties of the investigated samples.
