155 research outputs found
Una figura ancora poco decifrabile del Cinquecento religioso italiano. Vecchie e nuove questioni su Pomponio Algieri
No full textThis essay presents the unique and mysterious story of Pomponio Algieri, born in Nola, student of the University of Padua; he was persecuted for heresy and transferred from Venice to Rome, where he was executed in August 1556 under the intransigent Pope Paul IV Carafa. The paper takes its cue from the recent volume written by Umberto Vincenti, who tried to sum up Algieri’s story by exploiting the scientific literature and the available sources. The author reviews old and recent historiography which has focused on Pomponio Algieri and questions the “uniqueness” of his case, also reflecting on the possibilities of historical research to shed light on his religious and cultural background and on his uncommon fortitude in the face of a horrible death
Una figura ancora poco decifrabile del Cinquecento religioso italiano. Vecchie e nuove questioni su Pomponio Algieri
No full textInternational audienceThis essay presents the unique and mysterious story of Pomponio Algieri, born in Nola, student of the University of Padua; he was persecuted for heresy and transferred from Venice to Rome, where he was executed in August 1556 under the intransigent Pope Paul IV Carafa. The paper takes its cue from the recent volume written by Umberto Vincenti, who tried to sum up Algieri's story by exploiting the scientific literature and the available sources. The author reviews old and recent historiography which has focused on Pomponio Algieri and questions the "uniqueness" of his case, also reflecting on the possibilities of historical research to shed light on his religious and cultural background and on his uncommon fortitude in the face of a horrible death
Recruitment maneuvers in acute respiratory distress syndrome and during general anesthesia.
No full textThe use of low tidal volume ventilation and low to moderate PEEP levels is a widespread strategy to ventilate patients with non injured lungs during general anesthesia and in intensive care as well with mild to moderate acute respiratory distress syndrome (ARDS). Higher PEEP levels have been recommended in severe ARDS. Due to the presence of alveolar collapse, recruitment maneuver (RMs) by causing a transient elevation in airway pressure (i.e. transpulmonary pressure) has been suggested to improve the lung inflation in the not and in the poor inflated lung regions. Various type of RMs such as sustained inflation at high pressure, intermittent sighs and stepwise increases of PEEP and/or airway plateau inspiratory pressure have been proposed. The use of RMs has been associated with mixed results in terms of physiological and clinical outcomes. The optimal method for RMs has not yet been identified. The use of RMs is not standardized and left to the individual physician experience. Similarly to ARDS patients, RMs have been proposed to improve lung aeration during general anesthesia. Aim of this clinical review is to present the clinical evidence of RMs in patients during general anesthesia and with ARDS and as well their potential biological effects in experimental models of acute lung injury
The Prone Position in the Treatment of Patients with ARDS: Problems and Real Utility
No full textProne positioning is a life-saving treatment used in ARDS patients in order to improve oxygenation and reduce lung injury due to mechanical ventilation. The beneficial effects of this procedure are the result of complex mechanisms that cooperate in improving gas exchange and in reducing global “stress” and “strain” of the lung. Prone positioning seems to be more effective in extrapulmonary form of ARDS, where the main feature of the disease is represented by compression atelectasis in dependent lung regions caused by the gain in lung weight due to pulmonary edema. To date, it is recommended in ARDS patients that maintain a PaO2/FiO2ratio lower than 150 mmHg even after optimization of mechanical ventilation. However, only the patients who react to prone positioning with a decrease in PaCO2 show a real benefit in terms of survival rate. The relationship between improvement in gas exchange and patient outcome still remains unclear. This is not a maneuver free of complications, and it is important to balance risks and benefits associated with the procedure. An expert team is required to safely prone the patient and to reduce the incidence of adverse effects
Recruitment maneuvers in acute respiratory distress syndrome and during general anesthesia
No full textThe use of low tidal volume ventilation and low to moderate positive end-expiratory pressure (PEEP) levels is a widespread strategy to ventilate patients with non-injured lungs during general anesthesia and in intensive care as well with mild to moderate acute respiratory distress syndrome (ARDS). Higher PEEP levels have been recommended in severe ARDS. Due to the presence of alveolar collapse, recruitment maneuvers (RMs) by causing a transient elevation in airway pressure (i.e.Transpulmonary pressure) have been suggested to improve lung inflation in non-inflated and poorly-inflated lung regions. Various types of RMs such as sustained inflation at high pressure, intermittent sighs and stepwise increases of PEEP and/or airway plateau inspiratory pressure have been proposed. The use of RMs has been associated with mixed results in terms of physiological and clinical outcomes. The optimal method for RMs has not yet been identified. The use of RMs is not standardized and left to the individual physician based on his/her experience. Based on the same grounds, RMs have been proposed to improve lung aeration during general anesthesia. The aim of this review was to present the clinical evidence supporting the use of RMs in patients with ARDS and during general anesthesia and as well their potential biological effects in experimental models of acute lung injury
Experimental Investigation and RSM Modeling of the Effects of Injection Timing on the Performance and NOx Emissions of a Micro-Cogeneration Unit Fueled with Biodiesel Blends
No full textThe (partial or total) substitution of petro-diesel with biodiesel in internal combustion engines (ICEs) could represent a crucial path towards the decarbonization of the energy sector. However, critical aspects are related to the controversial issue of the possible increase in Nitrogen Oxides (NOx) emissions. In such a framework, the proposed study aims at investigating the effects of biodiesel share and injection timing on the performance and NOx emissions of a diesel micro combined heat and power (CHP) system. An experimental campaign has been conducted considering the following operating conditions: (i) a reference standard injection timing (17.2° BTDC), an early injection timing (20.8° BTDC), and a late injection timing (12.2° BTDC); (ii) low (0.90 kW), partial (2.45 kW), and full (3.90 kW) output power load; and (iii) four fuel blends with different biodiesel (B) shares (B0, B15, B30, and B100). Experimental data were also elaborated on thanks to the response surface modelling (RSM) technique, aiming at (i) quantifying the influences of the above-listed variables and their trends on the responses, and (ii) obtaining a set of predictive numerical models that represent the basis for model-based design and optimization procedures. The results show: (i) an overall improvement of the engine performance due to the biodiesel presence in the fuel blend —in particular, B30 and B100 blends have shown peak values in both electrical (29%) and thermal efficiency (42%); (ii) the effective benefits of late SOI strategies on NOx emissions, quantified in an overall average NOx reduction of 27% for the early-to-late injection, and of 16% for the standard-to-late injection strategy. Moreover, it has emerged that the NOx-reduction capabilities of the late injection strategy decrease with higher biodiesel substitution rates; through the discussion of high-prediction-capable, parametric, data-driven models, an extensive RSM analysis has shown how the biodiesel share promotes an increase of NOx whenever it overcomes a calculated threshold that is proportional to the engine load (from about 66.5% to 85.7% of the biodiesel share)
Clinical feasibility of "awake-ECMO” in acute respiratory failure
No full textIntroduction: Veno-venous extracorporeal membrane oxygenation (vv-ECMO) is nowadays safer due
to recent technical improvements and thus is increasingly used as a rescue therapy for acute respiratory
failure. Mechanical ventilation is the standard support for patient with respiratory failure, but can itself
damage the lung.
Objective: To explore vv-ECMO as an alternative to conventional mechanical ventilation in acute
respiratory failure, we tested feasibility of vv-ECMO in spontaneous breathing patients (“awake-
ECMO”).
Methods: We retrospectively analyzed all consecutive patients who underwent vv-ECMO support
from June 2012 to January 2015.
Results: A total of 48 patients with acute respiratory failure (30 acute respiratory distress syndrome -
ARDS, 7 acute exacerbation of chronic obstructive pulmonary disease - AECOPD, 11 end-stage
pulmonary disease bridged to lung transplantation - ESPD) were analyzed. Figure shows the number of
days on ECMO and on “awake-ECMO” for different patients’ categories. All ESPD and all out of one
AECOPD patients were successfully treated while spontaneous breathing, whereas only 26% of ARDS
patients could remove invasive ventilation and only during shorter time of ECMO support (p<0,001).
Patients who could not undergo “awake-ECMO” were sicker than “awake” patients (SOFA 9.1±3.4 vs
4.5±1.3, p<0,001). Reasons underlying the impossibility of weaning from ventilator ARDS patients
were pulmonary plasma-leakage (n=7), hemodynamic derangements (n=10), neurologic impairments
(n=4), bleeding (n=7), severe respiratory distress and hypoxemia (n=8).
Conclusion: vv-ECMO in awake spontaneous breathing patients is feasible as a bridge to lung
transplantation and in AECOPD patients, while in sick ARDS patients we were not able to use vv-
ECMO as an alternative to mechanical ventilation
Protective effect of melatonin on hypoxia/reoxygenation-impaired cellular respiration in aortic endothelial cells (pAECs): action on mitochondrial bioenergetics by targeting the F1FO ATPase
No full textThis dataset contains data from the evaluation of the effect of melatonin on isolated mitochondria from porcine heart and on a hypoxia/reoxygenation (H/R) model of porcine aortic endothelial cells (pAECs). The aim of the research was to verify the effect of melatonin on mitochondrial bioenergetics by performing structure/activity correlation studies, on its antioxidant effect towards anion superoxide (SOX) production, on the phenomenon of mitochondrial permeability transition pore (mPTP) opening involved in regulated cell death processes and the protective effect on H/R-induced damage towards bioenergetic parameters in an in vitro model on pAECs. The results, reported in “Melatonin_mitochondria_pAECs_Dataset.xlsx”, showed that melatonin has an inhibitory effect on Mg2+-activated F1FO-ATPase at low temperatures (“Different T_Arrhenius_Mg” sheet) and not at 37°C, the physiological temperature. However, in this latter condition melatonin exerts an inhibitory effect on the enzymatic activity of Ca2+-activated F1FO-ATPase (as reported in “Titration curves” sheet), a molecular condition related to mPTP opening. Uncompetitive inhibition (“Inhibition kinetics_Ca” sheet) is exerted by binding to a site in the hydrophilic F1 portion of the enzyme (“F1-ATPase” and “Mutual exclusion_NBD_Ca” sheets). Consistently, mPTP opening was also desensitized by melatonin (“CRC” sheet). Its inhibitory effect was confirmed on the oxidative phosphorylation (“OXPHOS Site I” and “OXPHOS Site II” sheets) process when mitochondria were energized from the first phosphorylation site (Complex I). Its antioxidant effect was confirmed on SOX production (“ROS_Site I” and “ROS_Site II” sheets), in isolated mitochondria, induced from phosphorylation site I (Complex I) and site II (Complex II). pAEC viability was impaired by melatonin starting at a dose of 5 mM. After hypoxia/reoxygenation (H/R) treatment, cells appeared detached and phenotypically modified and the presence of 1 mM melatonin during H/R restored the adherent monolayer and cell viability was not different from normoxia control cells (“pAEC viability” sheet). The damage induced by the H/R process is reflected in mitochondrial bioenergetic parameters and increased SOX production; melatonin exerts a protective effect, improving bioenergetic parameters and reducing SOX levels (“Metab_ROS pAEC_H_R” sheet)
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