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The prevalence of asthma has increased worldwide. Asthma exacerbations triggered by upper respiratory tract viral infections remain a major clinical problem and account for hospital admissions and time lost from work. Virus-induced asthma exacerbations cause airway inflammation, resulting in worsening asthma and deterioration in the patients' quality of life, which may require systemic corticosteroid therapy. Despite recent advances in understanding the cellular and molecular mechanisms underlying asthma exacerbations, current therapeutic modalities are inadequate for complete prevention and treatment of these episodes. The pathological role of cellular senescence, especially that involving the silent information regulator 2 homolog sirtuin (SIRT) protein family, has recently been demonstrated in stable and exacerbated chronic respiratory disease states. This review discusses the role of SIRT1 in the pathogenesis of bronchial asthma. It also discusses the role of SIRT1 in inflammatory cells that play an important role in virus-induced asthma exacerbations. Recent studies have hypothesized that SIRT1 is one of major contributors to cellular senescence. SIRT1 levels decrease in Th2 and non-Th2-related airway inflammation, indicating the role of SIRT1 in several endotypes and phenotypes of asthma. Moreover, several models have demonstrated relationships between viral infection and SIRT1. Therefore, targeting SIRT1 is a novel strategy that may be effective for treating virus-induced asthma exacerbations in the future.

No abstract is provided for this article.

<h3>BACKGROUND</h3> Nitric oxide (NO) may be bronchoprotective in asthma, possibly due to a direct action on airway smooth muscle or through mast cell stabilisation. To investigate this the effects of two doses of nebulised N^G-nitro-l-arginine methyl ester (l-NAME), a non-selective NO synthase (NOS) inhibitor, on exhaled NO levels and airway responsiveness to histamine, a direct smooth muscle spasmogen, and adenosine-5′-monophosphate (AMP), an indirect spasmogen which activates mast cells, were evaluated in patients with mild asthma. <h3>METHODS</h3> The study consisted of two phases each with a double blind, randomised, crossover design. In phase 1, 15 subjects inhaled either l-NAME 54 mg or 0.9% saline 30 minutes before histamine challenge. Nine of these subjects were studied in a similar fashion but were also challenged with AMP. In phase 2, 13 subjects (eight from phase 1) performed the same protocol but inhaledl-NAME in a dose of 170 mg or 0.9% saline before being challenged with histamine and AMP. <h3>RESULTS</h3> The mean (95% CI) reduction in exhaled NO levels after l-NAME 54 mg was 78% (66 to 90) but this did not alter airway responsiveness; the geometric mean (SE) concentration provoking a fall of 20% or more in forced expiratory volume in one second (PC₂₀) after l-NAME and saline was 0.59 (1.26) and 0.81 (1.26) mg/ml, respectively, for histamine and 20.2 (1.7) and 17.2 (1.6) mg/ml, respectively, for AMP. In contrast,l-NAME 170 mg reduced NO levels to a similar extent (81% (95% CI 76 to 87)) but increased airway responsiveness by approximately one doubling dose to both spasmogens; the geometric mean (SE) PC₂₀ for histamine after l-NAME 170 mg and saline was 0.82 (1.29) and 1.78 (1.19) mg/ml, respectively (p&lt;0.001), and for AMP was 11.8 (1.5) and 24.3 (1.4) mg/ml, respectively (p&lt;0.001). <h3>CONCLUSIONS</h3> These results suggest thatl-NAME increases airway responsiveness in asthma. This may occur through mechanisms separate from NO inhibition or through pathways independent of those responsible for production of NO measured in exhaled air.

Neutral endopeptidase (NEP) may regulate peptide-induced inflammation in the upper respiratory tract. NEP mRNA was detected by Northern blotting in poly(A)+ mRNA prepared from human turbinates. NEP mRNA bands were detected at 3.9 and 1.8 kb. In situ hybridization identified NEP mRNA in epithelial cells, serous cells of submucosal glands, and vessel walls. The vacuoles of goblet and mucous cells were not stained, but it is likely that the cytoplasm of these cells contained some NEP mRNA. Radioactive in situ hybridization with 35S-UTP appeared to be more sensitive than nonradioactive in situ hybridization with biotin-UTP and immunogold detection. The NEP mRNA-containing cells identified by in situ hybridization were the same as those identified by immunohistochemistry to contain immunoreactive NEP. These NEP-containing cells have been previously shown to possess peptide receptors. This is consistent with the hypothesis that NEP on cells bearing peptide receptors may regulate neuropeptide-induced inflammation in human nasal mucosa.

Objectives The aim of this study was to compare ticagrelor monotherapy with dual-antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) with drug-eluting stents. Background The role of abbreviated DAPT followed by an oral P2Y12 inhibitor after PCI remains uncertain. Methods Two randomized trials, including 14,628 patients undergoing PCI, comparing ticagrelor monotherapy with standard DAPT on centrally adjudicated endpoints were identified, and individual patient data were analyzed using 1-step fixed-effect models. The protocol was registered in PROSPERO (CRD42019143120). The primary outcomes were the composite of Bleeding Academic Research Consortium type 3 or 5 bleeding tested for superiority and, if met, the composite of all-cause death, myocardial infarction, or stroke at 1 year, tested for noninferiority against a margin of 1.25 on a hazard ratio (HR) scale. Results Bleeding Academic Research Consortium type 3 or 5 bleeding occurred in fewer patients with ticagrelor than DAPT (0.9% vs. 1.7%, respectively; HR: 0.56; 95% confidence interval [CI]: 0.41 to 0.75; p < 0.001). The composite of all-cause death, myocardial infarction, or stroke occurred in 231 patients (3.2%) with ticagrelor and in 254 patients (3.5%) with DAPT (HR: 0.92; 95% CI: 0.76 to 1.10; p < 0.001 for noninferiority). Ticagrelor was associated with lower risk for all-cause (HR: 0.71; 95% CI: 0.52 to 0.96; p = 0.027) and cardiovascular (HR: 0.68; 95% CI: 0.47 to 0.99; p = 0.044) mortality. Rates of myocardial infarction (2.01% vs. 2.05%; p = 0.88), stent thrombosis (0.29% vs. 0.38%; p = 0.32), and stroke (0.47% vs. 0.36%; p = 0.30) were similar. Conclusions Ticagrelor monotherapy was associated with a lower risk for major bleeding compared with standard DAPT, without a concomitant increase in ischemic events.

Aims To investigate the impact of established cardiovascular disease (CVD) on 10-year all-cause death following coronary revascularization in patients with complex coronary artery disease (CAD). Methods The SYNTAXES study assessed vital status out to 10 years of patients with complex CAD enrolled in the SYNTAX trial. The relative efficacy of PCI versus CABG in terms of 10-year all-cause death was assessed according to co-existing CVD. Results Established CVD status was recorded in 1771 (98.3%) patients, of whom 827 (46.7%) had established CVD. Compared to those without CVD, patients with CVD had a significantly higher risk of 10-year all-cause death (31.4% vs. 21.7%; adjusted HR: 1.40; 95% CI 1.08–1.80, p = 0.010). In patients with CVD, PCI had a non-significant numerically higher risk of 10-year all-cause death compared with CABG (35.9% vs. 27.2%; adjusted HR: 1.14; 95% CI 0.83–1.58, p = 0.412). The relative treatment effects of PCI versus CABG on 10-year all-cause death in patients with complex CAD were similar irrespective of the presence of CVD ( p -interaction = 0.986). Only those patients with CVD in ≥ 2 territories had a higher risk of 10-year all-cause death (adjusted HR: 2.99, 95% CI 2.11–4.23, p &lt; 0.001) compared to those without CVD. Conclusions The presence of CVD involving more than one territory was associated with a significantly increased risk of 10-year all-cause death, which was non-significantly higher in complex CAD patients treated with PCI compared with CABG. Acceptable long-term outcomes were observed, suggesting that patients with established CVD should not be precluded from undergoing invasive angiography or revascularization. Trial registration SYNTAX : ClinicalTrials.gov reference: NCT00114972. SYNTAX Extended Survival : ClinicalTrials.gov reference: NCT03417050. Graphic abstract

To validate a new two dimensional (2-D) bifurcation quantitative coronary angiography (QCA) software.In the latest edition of the Cardiovascular Angiography Analysis System (CAAS 5.9; Pie Medical Imaging, Maastricht, The Netherlands) video-densitometric information is dynamically integrated into the edge-detection algorithm of 11- and 6-segment models to reduce overestimation of small diameters. Furthermore, automatic reference obstruction analysis was optimised. Values of the minimal lumen diameter (MLD), reference vessel diameter (RVD), percent diameter stenosis (DS) and bifurcation angle (BA) for the different bifurcation segment models were validated against precision manufactured plexiglass phantoms. In anteroposterior views, accuracy and precision (mean difference±SD) of 11- and 6-segment models for MLD were 0.013±0.082 mm vs. 0.003±0.100 mm, for RVD -0.030±0.047 mm vs. -0.029±0.045 mm and for DS -0.48±3.66% vs. -0.11±3.97%. In smaller vessel segments (true MLD <0.7 mm), MLD overestimation was reduced. Inter-observer variability for MLD, RVD and DS for either model was ≤0.052 mm, ≤0.043 mm and ≤2.24%, respectively. Agreement between models for MLD, RVD and DS was ±0.076 mm, ±0.021 mm and ±2.53%, respectively. Accuracy and precision for BA were -2.6±3.5°, and variability was ≤1.2°. Accuracy and precision for diameter-derived parameters were slightly decreased in projections with 30° rotation; BA precision dropped to 6.2°.MLD quantification is improved for true MLD <0.7 mm, resulting in highly accurate and precise diameter measurements over the entire range of phantom diameters. Automatic reference obstruction analysis provides highly accurate, precise and reproducible RVD and DS measurements.

No abstract is provided for this article.

We have studied the effect of intravenous epinephrine, albuterol, verapamil, and aminophylline on airway microvascular leakage in guinea pigs. Microvascular leakage was induced by platelet-activating factor (PAF; 50 ng/kg intravenously), which acts directly on venular endothelial cells, and measured by quantifying extravasation of Evans blue (EB) dye. Epinephrine (20 µg/kg) inhibited PAF-induced changes in dye leakage in larynx and main bronchi; at 80 and 160 µg/kg, significant inhibition was observed in all airways studied. This effect was reversed by phentolamine (2.5 mg/kg) or prazosin (100 µg/kg). By contrast, albuterol (20 to 320 µg/kg) and aminophylline (12.5 to 50 mg/kg) failed to inhibit dye leakage at any dose studied. Verapamil inhibited PAF-increased leakage in larynx, main bronchi, and intrapulmonary airways at the lowest dose tested (125 µg/kg), although inhibition was not dose dependent. These results suggest that the antiedema effect of epinephrine may be due to vasoconstriction rather than to a direct effect on endothelial cell contractility and that neither β-agonists nor theophylline have an inhibitory effect. The inhibitory effect of epinephrine on airway microvascular leakage may have therapeutic implications for asthma.

We hypothesized that platelet-activating factor (PAF), a potent inflammatory mediator, could induce gas exchange abnormalities in normal humans. To this end, the effect of aerosolized PAF (2 mg/ml solution; 24 micrograms) on ventilation-perfusion (VA/Q) relationships, hemodynamics, and resistance of the respiratory system was studied in 14 healthy, nonatopic, and nonsmoking individuals (23 +/- 1 [SEM]yr) before and at 2, 4, 6, 8, 15, and 45 min after inhalation, and compared to that of inhaled lyso-PAF in 10 other healthy individuals (24 +/- 2 yr). PAF induced, compared to lyso-PAF, immediate leukopenia (P < 0.001) followed by a rebound leukocytosis (P < 0.002), increased minute ventilation (P < 0.05) and resistance of the respiratory system (P < 0.01), and decreased systemic arterial pressure (P < 0.05). Similarly, compared to lyso-PAF, PaO2 showed a trend to fall (by 12.2 +/- 4.3 mmHg, mean +/- SEM maximum change from baseline), and arterial-alveolar O2 gradient increased (by 16.7 +/- 4.3 mmHg) (P < 0.02) after PAF, because of VA/Q mismatch: the dispersion of pulmonary blood flow and that of ventilation increased by 0.45 +/- 0.1 (P < 0.01) and 0.29 +/- 0.1 (P < 0.04), respectively. We conclude that in normal subjects, inhaled PAF results in considerable immediate VA/Q inequality and gas exchange impairment. These results reinforce the notion that PAF may play a major role as a mediator of inflammation in the human lung.