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Elevated blood lactate levels are associated with poor outcome in several critical conditions. Patients with SARS-CoV-2 rarely develop hyperlactatemia. The purpose of this study is to evaluate the trend of lactatemia in patients affected by mild/moderate SARS-Co V-2-ARDS and if it affected prognosis. We analyzed blood lactate levels in thirty-eight patients with severe SARS-CoV-2 infection admitted to COVID Care Unit of Santa Maria delle Grazie Hospital, Pozzuoli. Twenty patients survived and were discharged at home and 18 patients died. Despite severe hypoxia that affected all patients enrolled, T0 lactate was within normal values. All survivors showed a significant increase in lactate concentration the day prior to clinical improvement. In not-survivors levels of lactate did not increase significantly. In our study, patients who survive SARS CoV-2 ARDS have a fleeting increase in lactate, which precedes clinical improvement by one day. [ABSTRACT FROM AUTHOR]

Abstract Objective To determine the thermal expansion of a porcelain (VM9) and tetragonal zirconia (Y-TZP) as well as the deflection upon re-heating and cooling of a bilayer fabricated from these two materials after slow and rapid cooling during initial fabrication. Methods The coefficient of thermal expansion (CTE) of bulk porcelain and Y-TZP as well as bilayer beam deflection was measured with a novel non-contact optical dilatometer. The influence of cooling rate during initial fabrication of the porcelain–zirconia bilayer and the bulk porcelain during subsequent heating and cooling is investigated. Specimens were heated to 900 °C in the dilatometer, well in excess of the glass transition temperature (T g) and softening temperature (T s) of the porcelain. Results The thermal expansion of the porcelain above T g exhibits a threefold increase in CTE over that observed below T g. Observations of the bilayer deflection reflect the difference in the CTE of the component materials and enable T g and T s temperatures for the porcelain to be estimated. Initial cooling rate of the porcelain and porcelain-YTZP bilayer was found to have a profound influence on the subsequent response to slow reheating and cooling as well as the resultant residual deflection. Significance The estimation of the residual stress and potential for chipping of porcelain–zirconia dental restorative systems should not be based solely on thermal expansion data measured below T g. [ABSTRACT FROM AUTHOR]

Pulmonary arterial hypertension (PAH) is a heart failure syndrome characterized by right ventricular (RV) to pulmonary circulation uncoupling, counteracted by the sympathetic nervous system activation leading to β 1 -receptors and α-myosin heavy chain downregulation, downregulation of the sarcoplasmic reticulum Ca2+ATPase, and β-myosin heavy chain upregulation. Increased ventilation (VE) associated with VE inefficiency further characterizes PAH, as shown by an elevated VE versus carbon dioxide relationship slope during exercise, reflecting a specific behavior with progressive increase of dead space (VD) VE. The sympathetic system interacts with chemoreceptor-mediated VE control with increased VD leading to VE/perfusion mismatch. Growing evidence in the experimental models shows beneficial effects of different adrenoreceptor blockers on both right heart and pulmonary artery morphology and function. These effects can significantly change among β-blockers according to their different pharmacokinetic and pharmacodynamic profiles. Since the first observation in the clinical setting, showing improvement associated with β-blocker withdraw in PAH patients, recent studies suggest that the effects of β-blockers in PAH might be related to the β 1 -adrenergic receptors selectivity and α 1 – and β 3 -related ancillary properties. While in the advanced stages of PAH β-blockers may result deleterious as counteract the compensatory adrenergic-mediated effects of low cardiac output, in the early stages the modulation of the adrenergic system could ultimately improve VE efficiency and promote beneficial effects on heart failure gene expression and RV remodeling, particularly β 1 -selective blockers and those associated with α- or β 3 -activities. At present, all the above are physiologically sound but clinically unproven suggestions, and need to be tested in future randomized controlled trials. [Display omitted] [ABSTRACT FROM AUTHOR]

Right ventricular function adaptation to afterload as assessed by the ratio of tricuspid annular plane excursion (TAPSE) to systolic pulmonary artery pressure (PASP) has been shown to be of prognostic relevance in pulmonary arterial hypertension (PAH).To test the hypothesis that improvement in TAPSE/PASP under targeted therapies is associated with the likelihood to achieve a better prognostic low-risk status in PAH. The study retrospectively enrolled 677 PAH patients (55 % idiopathic) with follow-up clinical, right heart catheterization and echocardiographic evaluations within 12 months (IQR 180-344 days) after initiation of targeted therapies from 2005 to 2017 in 11 Italian centers. European guidelines-derived and United States Registry to Evaluate Early and Long-Term PAH Disease Management registry REVEAL 2.0 risk scores were assessed at baseline and follow-up. The patients improved their functional class and 6-min walk distance, but a minority of them achieved or mainteined the low risk status as assessed either with the European or the REVEAL score (30% and 27%, respectively). The TAPSE/PASP ratio increased curvilinearly in proportion to decreased pulmonary vascular resistance (PVR) by more than 50 %. Patients at low risk were respectively, 4.93 and 3.37 times more likely to have TAPSE/PASP ≥ 0.35 mm/mmHg than those at intermediate or high risk, according to the ESC/ERS (OR 4.93, C.I. 3.40-7.14; p= 0.0001) and the REVEAL 2.0 score (OR 3.37, C.I. 2.32-4.90; p= 0.0001). Improvement of TAPSE/PASP under targeted therapies in PAH is associated with a low risk status and marked reduction in PVR. [ABSTRACT FROM AUTHOR]