Exosomal miR-17-5p, miR-146a-3p, and miR-223-3p Correlate with Radiologic Sequelae in Survivors of COVID-19-Related Acute Respiratory Distress Syndrome

We investigated the association between circulating microRNAs (miRNAs) potentially involved in the lung inflammatory process and fibrosis development among COVID-19-related acute respiratory distress syndrome (ARDS) survivors. At 4 ± 2 months from clinical recovery, COVID-19-related ARDS survivors matched for age, sex, and clinical characteristics underwent chest high-resolution computerized tomography (HRCT) and were selected based on imaging pattern evolution into fully recovered (N = normal), pulmonary opacities (PO) and fibrosis-like lesions (FL). Based on the previous literature, we performed plasma miRNA profiling of exosomal miRNAs belonging to the NLRP3-inflammasome platform with validated (miR-17-5p, miR-223-3p) and putative targets (miR-146a-5p), miRNAs involved in the post-transcriptional regulation of acute phase cytokines (miR128-3p, miR3168, miR125b-2-3p, miR106a-5p), miRNAs belonging to the NLRP4-inflammasome platform (miR-141-3p) and miRNAs related to post-transcriptional regulation of the fibrosis process (miR-21-5p). miR-17-5p, miR-223-3p, and miR-146a-5p were significantly down-regulated in patients with FL when compared to patients with PO. miR-146a-5p was also down-regulated in patients with FL than in N. The expression of the remaining miRNAs did not differ by group. In patients with long-term pulmonary radiological sequelae following COVID-19-related ARDS, a down-regulation of miR-17-5p, miR-146a-3p, and miR-223-3p correlated to fibrosis development in patients showing persistent hyper-reactivity to inflammatory stimulation. Our results support the hypothesis that NLRP3-Inflammasome could be implicated in the process of fibrotic evolution of COVID-19-associated ARDS.

Ascending aorta dilatation is associated to hard cardiovascular events, follow-up from multicentric ARGO-Perspective project

Aortic root dilatation has been proposed as hypertension-mediated organ damage (HMOD). Nevertheless, the role of the aortic root dilatation as a possible additional HMOD is still unclear since studies conducted so far are quite heterogeneous regarding the type of population analyzed, the aortic tract considered, and the type of outcomes accounted for. The aim of the present study is to assess whether the presence of aortic dilatation is associated with strong cardiovascular (CV) events (MACE: heart failure, CV death, stroke, acute coronary syndrome, myocardial revascularization) in a population of patients affected by essential hypertension. Four hundred forty-five hypertensive patients from six Italian hospitals were recruited as part of ARGO-SIIA study1. For all centers, follow-up was obtained by re-contacting all patients by telephone and through the hospital's computer system. Aortic dilatation (AAD) was defined through absolute sex-specific thresholds as in previous studies (41 mm for males, 36 mm for females). Median follow-up was 60 months. AAD was found to be associated with the occurrence of MACE (HR = 4.07 [1.81-9.17], p < 0.001). This result was confirmed after correction for main demographic characteristics such as age, sex and BSA (HR = 2.91 [1.18-7.17], p = 0.020). At penalized Cox regression, age, left atrial dilatation, left ventricular hypertrophy and AAD were identified as best predictor of MACEs and AAD resulted a significant predictor of MACEs even after correction for these confounders (HR = 2.43 [1.02-5.78], p = 0.045). The presence of AAD was found to be associated with an increased risk of MACE independently of for major confounders, including established HMODs. AAD ascending aorta dilatation, LAe left atrial enlargement, LVH left ventricular hypertrophy, MACEs major adverse cardiovascular events, SIIA Società Italiana dell'Ipertensione Arteriosa (Italian Society for Arterial Hypertension).

Relationship between measures of adiposity, blood pressure and arterial stiffness in adolescents. The MACISTE study

OBJECTIVE

Children and adolescents with adiposity excess are at increased risk of future cardiovascular (CV) disease. Fat accumulation promotes the development of elevated blood pressure (BP) and arterial stiffness, two main determinants of CV risk which are strongly inter-related. We aimed at investigating whether the association between overweight and arterial stiffness, taken at different arterial segments, is mediated by increased BP or is BP-independent.

METHODS

Three hundred and twenty-two Italian healthy adolescents (mean age 16.9±1.4 years, 12% with overweight) attending the "G. Donatelli" High School in Terni, Italy, underwent measurement of arterial stiffness by arterial tonometry (aortic stiffness) and semiautomatical detection of pressure-volume ratio of the common carotid (carotid stiffness). The mediator effect of BP was tested for each anthropometric or biochemical measure of fat excess related to arterial stiffness.

RESULTS

Both carotid and aortic stiffness showed positive correlations with body mass index, waist, hip, and neck circumferences (NC). Only carotid stiffness, but not aortic stiffness, was associated with serum markers of fat accumulation and metabolic impairment such as insulin, homeostatic model of insulin resistance (HOMA-IR), serum gamma-glutamyl transferase (sGGT) and uric acid. The association with NC was stronger for carotid than for aortic stiffness (Fisher z -to- R 2.07, P  = 0.04), and independent from BP.

CONCLUSIONS

In healthy adolescents, fat accumulation is associated with arterial stiffness. The degree of this association differs by arterial segments, since carotid stiffness is more strongly associated to adipose tissue excess than aortic stiffness and shows a BP-independent association with NC whereas aortic stiffness does not.

Importance of central BP assessment in ISH of the young. Which devices are best suited for practical use?

Isolated systolic hypertension (ISH), defined as brachial systolic blood pressure (bSBP) ≥140 mmHg and diastolic blood pressure (DBP) <90 mmHg, is highly prevalent among young subjects and in the elderly. The prognostic significance of ISH in young individuals remains the object of large debate which might be solved, at least in part, if considering the prognostic role of central BP. For any given value of pBP, the cardiovascular (CV) risk is better defined by central BP (cBP). Young individuals with ISH have long been considered at low CV risk, given the assumption that a "spurious hypertension" phenotype characterized by elevated peripheral (brachial) BP (pBP), normal cBP, and elevated BP amplification was often found in this population. However, this remains to be proven, because many other studies found no differences in BP amplification between ISH and sisto-diastolic hypertension. Despite numerous attempts, methodologies for cBP assessment by non-invasive devices are currently not standardized. As a result, different devices could provide different cBP values despite using the same biological signals. Devices providing accurate estimates of BP amplification as a dimensionless ratio between amplitudes of central and peripheral arterial waveforms might be well suited for clinical purposes in young individuals with ISH. There is urgent need of well-designed prospective studies aiming at longitudinally evaluating the amount of CV risk associated with elevated cBP in young subjects with ISH and their related incremental prognostic value.

Handgrip strength is associated with adverse outcomes in patients hospitalized for COVID-19-associated pneumonia

Handgrip strength (HGS), a simple tool for the evaluation of muscular strength, is independently associated with negative prognosis in many diseases. It is unknown whether HGS is prognostically relevant in COVID-19. We evaluated the ability of HGS to predict clinical outcomes in people with COVID-19-related pneumonia. 118 patients (66% men, 63 ± 12 years), consecutively hospitalized to the "Santa Maria" Terni University Hospital for COVID-19-related pneumonia and respiratory failure, underwent HGS measurement (Jamar hand-dynamometer) at ward admission. HGS was normalized to weight^2/3 (nHGS) The main end-point was the first occurrence of death and/or endotracheal intubation at 14 days. Twenty-two patients reached the main end-point. In the Kaplan-Meyer analysis, the Log rank test showed significant differences between subjects with lower than mean HGS normalized to weight^2/3 (nHGS) (< 1.32 kg/Kg^2/3) vs subjects with higher than mean nHGS. (p = 0.03). In a Cox-proportional hazard model, nHGS inversely predicted the main end-point (hazard ratio, HR = 1.99 each 0.5 kg/Kg^2/3 decrease, p = 0.03), independently from age, sex, body mass index, ratio of partial pressure arterial oxygen and fraction of inspired oxygen (PaO₂/FiO₂ ratio), hypertension, diabetes, estimated glomerular filtration rate and history of previous cardiovascular cardiovascular disease. These two latter also showed independent association with the main end-point (HR 1.30, p = 0.03 and 3.89, p < 0.01, respectively). In conclusion, nHGS measured at hospital admission, independently and inversely predicts the risk of poor outcomes in people with COVID-19-related pneumonia. The evaluation of HGS may be useful in early stratifying the risk of adverse prognosis in COVID-19.

VACCINE-INDUCED MASSIVE PULMONARY EMBOLISM AND THROMBOCYTOPENIA FOLLOWING A SINGLE DOSE OF JANSSEN AD26.COV2.S VACCINATION

Vaccine-induced immune thrombotic thrombocytopenia (VITT) has emerged as a rare side effect of adenoviral vector-based vaccines against Coronavirus disease 2019 (COVID-19), and it is most frequently reported after Vaxzevria (AstraZeneca) vaccine. We described a case of severe thrombocytopenia associated with massive pulmonary embolism and portal vein thrombosis, occurring 13 days after the administration of the single dose adeno viral vector-based vaccine Ad26.COV2.S (Janssen vaccines, Leiden, Netherlands). Based on an early clinical suspect, the patient quickly received treatment with corticosteroids and intravenous immunoglobulins, followed by a rapid increase in platelet count that allowed full dose anticoagulation to be timely administered. Treatment with intravenous immunoglobulins, however, could mask the ability of anti-PF4-heparin antibodies to bind and activate platelets in the presence of heparin, leading to false negative results at the immunoassay functional test. Therefore, if VITT is suspected, blood samples for diagnostic confirmation should be collected prior to any treatment to improve diagnostic performance.

Mid-term impact of mild-moderate COVID-19 on cardiorespiratory fitness in élite athletes

BACKGROUND

Mid- and long-term sequelae of COVID-19 on cardiorespiratory fitness are unknown. Aim of the study was to assess the mid-term impact of mild-moderate COVID-19 on cardiorespiratory fitness evaluated by cardiopulmonary exercise testing (CPET) in élite athletes.

METHODS

13 elite cross-country skiers with previous mild-moderate COVID-19 symptoms underwent CPET before resuming seasonal training (COVID athletes). 13 élite detrained cross-country skiers, matched for principal confounding factors, were taken as controls (control group). Resting peripheral oxygen saturation, pulmonary function test, echocardiography, bioelectrical impedance analysis and CPET (modified XELG2, Woodway, USA) were performed in all participants.

RESULTS

Median recovery time in COVID athletes was 34 days (IQR 33-38 days). COVID athletes reached earlier the onset of the aerobic threshold (4'48" vs 6'28", R2=0.15, F=4.37, p<0.05)than controls, whereas the time to anaerobic threshold and maximal efforts did not significantly differ between groups. Oxygen consumption was lower at the aerobic threshold in COVID athletes than controls (VO2/kg 28.6 mL/min vs. 38.9 mL/min, R2=0.39, F=15.34, p<0.01), whereas no significant difference between groups was found both at the aerobic threshold and at peak exercise (all p<0.05). Findings from resting echocardiography and pulmonary function test were similar between the two groups.

CONCLUSIONS

Élite cross-country athletes, previously affected by mild-moderate COVID-19, reached earlier the aerobic threshold than controls, whereas the remaining CPET parameters did not differ between groups. Such changes were not associated with any detectable difference in resting pulmonary and cardiac examination. Subjects affected by mild-moderate COVID-19 may require a longer time course of re-adaptation to aerobic exercise.

Efficacy of convalescent plasma therapy in immunocompromised patients with COVID-19: A case report

BACKGROUND

Management of immunocompromised COVID-19 patients is the object of current debate. Accumulating evidence suggest that treatment with high-titer COVID-19 convalescent plasma (CCP) may be effective in this characteristic clinical scenario.

CASE REPORT

A 52-years old immunocompromised female patient, previously treated with rituximab for low grade B-cell lymphoma, showed prolonged SARS-CoV-2 shedding and a long-term course of signs of severe COVID-19. A first cycle of treatment with remdesivir, a nucleotide analogue prodrug effective in inhibiting SARS-CoV-2 replication, did not provide fully and sustained clinical remission. A second hospitalization was deemed necessary after 10 days from the first hospital discharge due to recrudescence of symptoms of severe COVID-19 and the evidence of bilateral interstitial pneumonia at the chest-CT scan. Clinical and radiological findings completely disappeared after CCP administration. The viral culture confirmed the absence of SARS-CoV-2-related cytopathic effect. The clinical evaluation, performed two months after hospital discharge, was unremarkable.

RESULTS

Findings from our case report suggest that the host T-cell specific response to SARS-CoV-2 is not sufficient to reduce viral load in the absence of neutralizing antibodies. Acquired immune antibodies and/or related components passively infused with CCP might help in boosting the plasma recipient response to the virus and promoting complete viral clearance.

CONCLUSIONS

Independently from negative results in immunocompetent individuals, the potential effectiveness of CCP infusion in selected cohorts of patients with primary or secondary impaired immune response should be tested. Further research about mechanisms of host response in immunocompromised patients with SARS-CoV-2 infection is required.

A molecular dynamics approach to the structural characterization of amyloid aggregation

A novel computational approach to the structural analysis of ordered beta-aggregation is presented and validated on three known amyloidogenic polypeptides. The strategy is based on the decomposition of the sequence into overlapping stretches and equilibrium implicit solvent molecular dynamics (MD) simulations of an oligomeric system for each stretch. The structural stability of the in-register parallel aggregates sampled in the implicit solvent runs is further evaluated using explicit water simulations for a subset of the stretches. The beta-aggregation propensity along the sequence of the Alzheimer's amyloid-beta peptide (Abeta(42)) is found to be highly heterogeneous with a maximum in the segment V(12)HHQKLVFFAE(22) and minima at S(8)G(9), G(25)S(26), G(29)A(30), and G(38)V(39), which are turn-like segments. The simulation results suggest that these sites may play a crucial role in determining the aggregation tendency and the fibrillar structure of Abeta(42). Similar findings are obtained for the human amylin, a 37-residue peptide that displays a maximal beta-aggregation propensity at Q(10)RLANFLVHSSNN(22) and two turn-like sites at G(24)A(25) and G(33)S(34). In the third application, the MD approach is used to identify beta-aggregation "hot-spots" within the N-terminal domain of the yeast prion Ure2p (Ure2p(1-94)) and to design a double-point mutant (Ure2p-N4748S(1-94)) with lower beta-aggregation propensity. The change in the aggregation propensity of Ure2p-N4748S(1-94) is verified in vitro using the thioflavin T binding assay.