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Substantial evidence supports the involvement of the renin-angiotensin system in pulmonary hypertension (PH), and the angiotensin II type 2 receptor (AT2R) is known to exert tissue protective actions. The effect of the selective AT2R agonist C21 (also known as Compound 21 or buloxibutid) was evaluated in the rat Sugen-hypoxia PH model. After a single injection of Sugen 5416 and hypoxia for 21 days, C21 (2 or 20 mg/kg) or vehicle was administered perorally twice daily from Day 21 to Day 55. On Day 56, hemodynamic assessments were performed, and lung and heart tissue were prepared for quantification of cardiac and vascular remodeling and fibrosis. Treatment with C21 20 mg/kg improved cardiac output and stroke volume and decreased right ventricular hypertrophy (all p < 0.05). Treatment with C21 2 mg/kg significantly decreased vessel wall and muscular layer thickness and increased the luminal opening in vessels >100 μm (all p < 0.05). There were no significant differences between the two C21 doses on any parameter, and post hoc analyses comparing the merged C21 groups with the vehicle group showed that C21 treatment reduced vascular remodeling (reduced endothelial proliferation and thickening of the vascular wall) in vessels of all sizes; moreover, the diastolic pulmonary artery pressure and right ventricular pressure were reduced along with reduction of right ventricular hypertrophy. Sugen 5416 and hypoxia increased pulmonary collagen deposition, which was counteracted by C21 20 mg/kg. In conclusion, the effects of C21 on vascular remodeling, hemodynamic alterations, and fibrosis suggest that AT2R agonists may have a role in Group 1 and 3 PH treatment. [ABSTRACT FROM AUTHOR]

Objective Our main aim was to investigate the effect of a single oral dose of C21, a selective angiotensin II type 2 receptor agonist, on cold-induced vasoconstriction in SSc-related RP. Methods This was a phase IIa, randomized, double-blind, cross-over, single-dose, placebo-controlled, single-centre study. Twelve female patients with SSc (median age 58.5 years, median duration of RP 19.0 years) attended on four occasions: screening, treatment visits 1 and 2 (separated by 3–7 days) and follow-up. At the first treatment visit, patients were randomized to receive either a single oral dose of C21 (200 mg) or placebo, then the opposite treatment on the second visit. Forty min after each treatment, each patient underwent a standard hand cold challenge. The primary end point was the area under the curve (AUC) for rewarming for each finger (eight fingers) over 15 min. Secondary end points included the maximum finger temperature after rewarming (MAX). Statistical analyses were performed by multiplicative ANCOVA models. Results For all eight fingers combined, mean AUC for rewarming was higher after treatment with C21 than after placebo (geometric mean 20 046°C*s vs 19 558°C*s), but not significantly (P  = 0.380) and MAX (at 15 min) was also higher (geometric mean 23.5°C vs 22.5°C; P  = 0.036). C21 was well tolerated. Conclusion Despite the small trial size, a signal emerged suggesting that even in patients with established SSc, C21 may confer benefit for RP and deserves further investigation. Trial registration ClinicalTrials.gov, https://clinicaltrials.gov , NCT04388176. [ABSTRACT FROM AUTHOR]

Abstract Background Chronic obstructive pulmonary disease (COPD) is characterized by inflammation and remodeling of the lungs. This results in alterations in extracellular matrix (ECM) and structural changes leading to airflow obstruction. We studied the expression of tenascin-C (Tn-C) and alpha smooth muscle actin (α-SMA), which act as a marker of myofibroblasts, in large airways from COPD patients. Our aim was to elucidate whether this expression correlated with smoking or with disease development. Methods Bronchoscopy was performed on 20 COPD patients (mean age 56 years; range 39-61; FEV1/FVC < 70% and FEV1 median 53% (range 33-69) of predicted). Age and smoking matched smokers (S) without COPD (n = 13) and age matched non-smokers (NS) (n = 14) served as controls. Bronchial mucosal biopsies were analyzed by immunohistochemistry. The distribution of Tn-C expression was assessed and graded in three levels, and the number of spindle shaped cells staining positive for α-SMA were counted. Results Biopsies from COPD patients had more (P < 0.001) Tn-C expression than the two control groups. A significantly (P < 0.05) increased number of spindle shaped cells expressing α-SMA was observed in COPD patients compared with the controls. Smokers and nonsmokers did not differ in this respect. The expression of Tn-C correlated positively (P < 0.001) to the number of α-SMA positive cells. Conclusions We demonstrate increased expression of Tn-C and α-SMA positive cells in the large airways in COPD. This was not associated to smoking per se, but to the presence of airway obstruction. Our findings add new information regarding remodeling characteristics and highlight the large airways as a potential site for airways obstruction in COPD.

Objective: The link and interplay between different airway exposures and rheumatoid arthritis (RA) risk are unclear. This study was undertaken to determine whether respiratory disease is associated with development of RA, and specifically to examine this relationship by RA serostatus and smoking exposure. Methods: Using data from the Epidemiological Investigation of Rheumatoid Arthritis study, this analysis included 1,631 incident RA cases and 3,283 matched controls recruited from 2006 to 2016. Linking these individuals to the National Patient Register provided information on past acute or chronic, upper or lower respiratory disease diagnoses. For each disease group, we estimated adjusted odds ratios (ORadj) with 95% confidence intervals (95% CI) for RA, using logistic regression models adjusted for age, sex, residential area, body mass index, and education both overall and stratified by anti–citrullinated protein antibody (ACPA)/rheumatoid factor (RF) status and by smoking status. Results: Respiratory disease diagnoses were associated with risk of RA, with an ORadj of 1.2 for acute upper respiratory disease (95% CI 0.8–1.7), 1.4 for chronic upper respiratory disease (95% CI 1.1–1.9), 2.4 for acute lower respiratory disease (95% CI 1.5–3.6), and 1.6 for chronic lower respiratory disease (95% CI 1.5–3.6). These associations were present irrespective of RF or ACPA status, though the association was somewhat stronger for ACPA/RF–positive than ACPA/RF–negative RA. The association between any respiratory disease and RA was stronger for nonsmokers (ORadj 2.1 [95% CI 1.5–2.9]) than for smokers (ORadj 1.2 [95% CI 0.9–1.5]). Conclusion: Respiratory diseases increase the risk for both seropositive and seronegative RA, but only among nonsmokers. These findings raise the hypothesis that smoking and airway disease are associated with RA development through partly different mechanisms. [ABSTRACT FROM AUTHOR]

Background: Smokers have increased cell concentration in the lower respiratory tract indicating a chronic inflammatory state, which in some individuals may lead to development of chronic obstructive pulmonary disease (COPD). Computer tomography (CT) imaging provides means of quantifying pulmonary structure and early signs of disease. We investigated whether lung density on high resolution CT differs between smokers and never-smokers and if this were associated to intensity of inflammation. Methods: Forty smoking volunteers with normal pulmonary function, 40 healthy never-smokers and 40 patients with COPD of GOLD stage I-II, were included. Mean lung attenuation and percentage of pixels in the lung with attenuation between -750 and -900 HU (percentage higher density spectrum (%HDS)) were calculated on inspiratory CT-scans. Markers of systemic inflammation in blood and cell counts in bronchoalveolar lavage (BAL) fluid were recorded. Results: Lung density expressed as %HDS was increased in smokers (44.0 ± 5.8%) compared to both never-smokers (38.3 ± 5.8%) and patients with COPD (39.1 ± 5.8%), (p < 0.001, for both). Females had denser lungs than males, which was dependent on body height. Cell concentration in BAL were correlated to lung density in smokers (r = 0.50, p < 0.001). Conclusions: Lung density on CT is associated with cell concentration in BAL in smokers andmay mirror an inflammatory response in the lung. Gender difference in lung density is dependent on height. In COPD with emphysema, loss of lung tissue may counterbalance the expected increase in density due to inflammation. The findings may help to interpret high resolution CT in the context of smoking and gender and highlight the heterogeneity of structural changes in COPD. [ABSTRACT FROM AUTHOR]

Objectives: To estimate the effects of smoking, gender and occupational exposure on the risk of developing severe pulmonary fibrosis (PF), including dose-response and interaction effects. Methods: National case--control study of 171 patients (cases) who had started a long-term oxygen therapy for PF in Sweden between February 1997 and April 2000, and 719 random control participants from the general population. Of these cases, 137 had probable idiopathic PF (IPF). The ORs for smoking, gender and occupational exposure were estimated using Mantel- Haenszel analysis and conditional logistic regression, controlling for age and year of diagnosis. Results: The adverse effect of smoking was amplified by male gender and occupational exposure, OR 4.6 (95% CI 2.1 to 10.3) for PF, and OR 3.0 (1.3 to 6.5) for IPF, compared with in non-exposed women. Higher cumulative smoking exposure was linearly associated with increased risks. Compared with smoking less than 10 pack-years, smoking ≥20 pack-years was associated with increased risk of PF and IPF, OR 2.6 (1.4 to 4.9) and OR 2.5 (1.3 to 5.0), respectively. Conclusions: Smoking has a dose-related association with increased risk of severe PF. Men with a history of smoking and occupational exposure is a particular risk group for developing severe PF. [ABSTRACT FROM AUTHOR]

Background: Clinical interpretation of bronchoalveolar lavage fluid results is dependent on the availability of reference values for healthy individuals. Only a few studies have published such reference values and the applicability of results is restricted by small sample sizes and the limited representativeness of the study population. We aim to investigate the influence of age, gender, collection site and season on bronchoalveolar lavage fluid results and to establish reference values for use in clinical practice. Methodology/Principal Findings: Bronchoalveolar lavage fluid data from 295 healthy never-smoking volunteers, investigated during 1990-2009, were analyzed retrospectively. 47 volunteers had 2-5 repeat lavages during the course of several years. Fluid recovery, total number of cells, cell concentration, and differential cell counts on cytospin prepared slides were recorded. Reference values, as represented by the 5th to the 95th percentile, were 72-96% for macrophages, 2-26% for lymphocytes, 0-4% for neutrophils and 0-1% for eosinophils. Basophils and mast cells were rare. When repeat lavages were performed, there was a relatively large intra-individual variability, mainly for macrophages and lymphocytes. An age dependent decrease of lavage fluid return was present, but there was no age dependent correlation with any of the other BALF parameters. The BALF cell parameters were independent of gender, season and site (lingula vs. middle lobe). Conclusions/Significance: Our data show that bronchoalveolar lavage fluid cell differential count is independent of age, gender, season and collection site (RML or lingua). It therefore seems acceptable to use the same reference values for all never-smoking individuals. [ABSTRACT FROM AUTHOR]

Background: Smoking is a risk factor for various lung diseases in which BAL may be used as a part of a clinical investigation. Interpretation of BAL fluid cellularity is however difficult due to high variability, in particular among smokers. In this study we aimed to evaluate the effect of smoking on BAL cellular components in asymptomatic smokers. The effects of smoking cessation, age and gender were also investigated in groups of smokers and exsmokers. Methods: We performed a retrospective review of BAL findings, to our knowledge the largest single center investigation, in our department from 1999 to 2009. One hundred thirty two current smokers (48 males and 84 females) and 44 ex-smokers (16 males and 28 females) were included. A group of 295 (132 males and 163 females) never-smokers served as reference. Result: The median [5-95 pctl] total number of cells and cell concentration in current smokers were 63.4 [28.6-132.1]×106 and 382.1 [189.7-864.3] ]×106/L respectively and correlated positively to the cumulative smoking history. Macrophages were the predominant cell type (96.7% [90.4-99.0]) followed by lymphocytes (2% [0.8-7.7]) and neutrophils (0.6% [0-2.9]). The concentration of all inflammatory cells was increased in smokers compared to never smokers and ex-smokers. BAL fluid recovery was negatively correlated with age (p<0.001). Smoking men had a lower BAL fluid recovery than smoking women. Conclusion: Smoking has a profound effect on BAL fluid cellularity, which is dependent on smoking history. Our results performed on a large group of current smokers and ex-smokers in a well standardized way, can contribute to better interpretation of BAL fluid cellularity in clinical context. [ABSTRACT FROM AUTHOR]

Background: Chronic obstructive pulmonary disease (COPD) is characterized by inflammation and remodeling of the lungs. This results in alterations in extracellular matrix (ECM) and structural changes leading to airflow obstruction. We studied the expression of tenascin-C (Tn-C) and alpha smooth muscle actin (α-SMA), which act as a marker of myofibroblasts, in large airways from COPD patients. Our aim was to elucidate whether this expression correlated with smoking or with disease development. Methods: Bronchoscopy was performed on 20 COPD patients (mean age 56 years; range 39-61; FEV1/FVC < 70% and FEV1 median 53% (range 33-69) of predicted). Age and smoking matched smokers (S) without COPD (n = 13) and age matched non-smokers (NS) (n = 14) served as controls. Bronchial mucosal biopsies were analyzed by immunohistochemistry. The distribution of Tn-C expression was assessed and graded in three levels, and the number of spindle shaped cells staining positive for α-SMA were counted. Results: Biopsies from COPD patients had more (P < 0.001) Tn-C expression than the two control groups. A significantly (P < 0.05) increased number of spindle shaped cells expressing α-SMA was observed in COPD patients compared with the controls. Smokers and nonsmokers did not differ in this respect. The expression of Tn-C correlated positively (P < 0.001) to the number of α-SMA positive cells. Conclusions: We demonstrate increased expression of Tn-C and α-SMA positive cells in the large airways in COPD. This was not associated to smoking per se, but to the presence of airway obstruction. Our findings add new information regarding remodeling characteristics and highlight the large airways as a potential site for airways obstruction in COPD. [ABSTRACT FROM AUTHOR]

The article discusses a prospective study in which newly diagnosed polymyositis/dermatomyositis (PM/DM) patients, regardless of pulmonary disease symptoms, were examined with repeated chest radiography, high-resolution computed tomography (HRCT) of the lungs, and pulmonary function test (PFT). Results found that patients with interstitial lung disease (ILD) had lower lung function, higher radiologic scores, and higher creatine kinase values than those without ILD.

Summary: Background: External agents, especially metal and wood dust, are believed to be risk factors for development of idiopathic pulmonary fibrosis (IPF). The aim of this case–control study was to investigate which occupational exposure types are associated with development of severe pulmonary fibrosis (PF), and especially IPF. Methods: An extensive postal questionnaire including 30 specific items regarding occupational exposure was completed by 181 patients with severe PF and respiratory failure reported to the Swedish Oxygen Register, among whom 140 were judged as having IPF. The questionnaire was also completed by 757 control subjects. We stratified data for age, sex and smoking and calculated odds ratios (ORs). Results: We found increased risk for IPF in men with exposure to birch dust (OR 2.7, 95% confidence interval (95% CI) 1.30–5.65) and hardwood dust (OR 2.7, 95% CI 1.14–6.52). Men also had slightly increased ORs associated with birds. We did not find any increased risk in association with metal dust exposure. Conclusion: Exposure for birch and hardwood dust may contribute to the risk for IPF in men. [Copyright &y& Elsevier]

Summary: Formoterol is a long-acting β 2-agonist with a rapid onset of effect in patients with chronic obstructive pulmonary disease (COPD), making it potentially suitable for both maintenance and as-needed bronchodilator treatment. To evaluate the efficacy and tolerability of maintenance formoterol in patients with COPD and to compare the effects of additional formoterol as needed with terbutaline. In this 6-month, double-blind study, 657 patients with COPD (⩾40 years, forced expiratory volume in 1s [FEV1] 40–70% predicted normal) were randomized to formoterol 9μg twice daily (bid) plus terbutaline 0.5mg as needed (FORM bid), formoterol 9μg bid plus formoterol 4.5μg as needed (FORM bid+prn), or placebo bid plus terbutaline 0.5mg as needed (placebo), all administered via Turbuhaler®. Primary efficacy variables were FEV1 and the sum of breathlessness and chest tightness scores combined symptom score. Formoterol significantly () increased FEV1 compared with placebo: FORM bid 6.5% (95% CI: 2.5, 10.7%); FORM bid+prn 11.8% (95% CI: 7.7, 16.2%). Combined symptom score decreased significantly in both formoterol groups compared with placebo: FORM bid −0.27 (95% CI: −0.49, −0.06; ); FORM bid+prn −0.32 (95% CI: −0.53, −0.11; ). Similar significant () improvements were seen in both formoterol groups for morning peak expiratory flow, cough and sleep scores, and reliever use. In this study, formoterol 9μg bid via Turbuhaler® as maintenance therapy, with either formoterol or terbutaline as rescue medication, provided sustained improvements in lung function and COPD symptoms. Both formoterol regimens were well tolerated with no differences in adverse events or electrocardiogram profiles. [Copyright &y& Elsevier]

Different ways to describe historic fibre exposure from asbestos-containing friction materials were studied and compared for a group of 103 car and bus mechanics with more than 20 years employment and 15 years of asbestos exposure. A model was constructed to calculate cumulative asbestos exposure from friction materials including duration, intensity and exposure last year. The model is a combination of an additive and a multiplicative model, where an asbestos index was constructed that takes both near field and far field exposure into consideration. The model was based upon data from the international literature and quantitative asbestos measurements performed 1976–1988 in Swedish car repair workshops. The fibres were counted by phase-contrast microscopy with fibre criteria of length <5 μm and aspect ratio ≥3:1. The mechanics' fibre exposure at 398 repair workshops during a period of 48 years were calculated using the model. The mean cumulative exposure was estimated to be 2.6 f ml * year. The annual cumulative exposure was highest for truck mechanics in the early 1960s. The car mechanics had a time-weighted average fibre exposure range of 0.11–041 f ml (mean 0.21 f ml) in 1965 compared to 0.003–0.08 f ml (mean 0.021 f ml) in 1985. In order to validate the model, the mechanics' fibre exposure estimated using the model were compared with representative asbestos exposure measurements for car mechanics during the 1960s and the 1970s (correlation coefficient =0.69). Five lung physiological variables (FVC, TLC, FEV TL and CV%) were used to study exposure-response relationships. None of the exposure parameters suggested any significant relationship between exposure and decrease in lung function. [ABSTRACT FROM PUBLISHER]

Background: Active smoking is the most important risk factor for pulmonary emphysema in subjects with severe alpha 1-antitrypsin (AAT) deficiency. The aim of this study was to analyse the effects of environmental risk factors other than active smoking on lung function and on respiratory symptoms in non-smoking PiZZ individuals.Methods: Lifetime exposure to passive smoking, domiciliary use of a kerosene (paraffin) heater or gas cooker, and all occupations since leaving school were reported by 205 non-smoking PiZZ individuals (95 men and 110 women) included in the Swedish AAT deficiency register. Lung function test results and histories of respiratory symptoms (chronic bronchitis, recurrent wheezing, and exertional dyspnoea) were elicited from the AAT register records.Results: After adjustment for age, agricultural employment and domiciliary kerosene heater usage, but not gas cooker usage or passive smoking, were both associated with significantly decreased lung function. Multiple linear regression analysis showed age, sex, kerosene heater usage, and agricultural employment to be independent determinants of lung function impairment. Age and passive smoking for 10 years or more, both at home and at the work place, were associated with the presence of chronic bronchitis. Age and agricultural employment for > or = 10 years were associated with recurrent wheezing and exertional dyspnoea.Conclusions: Domiciliary kerosene heater usage and an agricultural occupation therefore appear to be environmental factors associated with decreased lung function in non-smoking PiZZ individuals, and passive smoking is associated with an increased frequency of chronic bronchitis, but not with impaired lung function. [ABSTRACT FROM AUTHOR]

Background: Severe alpha 1-antitrypsin (AAT) deficiency (PiZZ) is associated with an increased risk of lung emphysema, especially in smokers. The aim of this study was to identify risk factors other than smoking for declining lung function.Methods: Lung function was studied in 225 self-reported never-smoking PiZZ individuals included in the Swedish AAT deficiency register.Results: Lung function was poorer in men than in women (mean (SD) forced expiratory volume in one second (FEV1) 80 (30) versus 88 (17)% predicted) despite the fact that the men were younger (mean (SD) age 45 (18) versus 51 (17) years), and poorer in those aged 50 or older than in those aged under 50 (mean (SD) FEV1 70 (30) versus 98 (16)% predicted). Self-reported occupational exposure to gas, fumes, or dust occurred more frequently in men than in women. In those aged 50 or older lung function was lower in individuals exposed to airway irritants than those who were not exposed (mean (SD) FEV1 63 (29) versus 76 (31)% predicted). Male sex, increasing age, and previous symptoms of wheezing were independent risk factors for lung function impairment, and male sex, wheeziness, and occupational exposure to airway irritants were independent risk factors in the subjects aged 50 years or more.Conclusions: In non-smoking PiZZ individuals lung function declines with increasing age, especially after 50. Men are at greater risk of lung function deterioration than women. Asthmatic symptoms and occupational exposure to airway irritants appear to constitute additional risk factors. [ABSTRACT FROM AUTHOR]

Contrasts rat alveolar and interstitial macrophages weeks after quartz exposure. Role of macrophages in pulmonary host defense; Interstitial macrophages as immunocompetent cells; Absence of effect on the addition of surfactant; Association of quartz exposure with inflammatory cell response.

Genetically based differences in metabolism, related to I restriction site and Ile-Val polymorphisms of the cytochrome P450 (CYP) 1A1 gene and the null genotype of glutathione transferase class mu (GSTM1), have been reported to be associated with lung cancer susceptibility. The present study was set up to establish the frequencies of the polymorphic genotypes of CYP1A1 and GSTM1 in Sweden, to evaluate a possible increased incidence of the genotypes associated with higher lung cancer risks among Swedish lung cancer patients and to try to make a combined risk estimate for carriers of multiple risk alleles. In a healthy control group, all under 66 years of age, 53% (174/329) of the subjects were of the GSTM1(−) genotype, while in a hospital control group 49% (39/79) carried the GSTM1(−) genotype. In the investigated lung cancer patients this genotype was found in 56% (165/296) and among those patients diagnosed before 66 years of age the deficient genotype was found in 60% (78/131). The highest proportion of the GSTM1(−) genotype was found in patients diagnosed with adenocarcinoma (63%, 29/46) and small cell carcinoma (72%, 21/29) before 66 years of age and among female squamous cell carcinoma patients (79%, 15/19). The allelic variants in CYP1A1 were equally distributed in lung cancer patients and controls. The m1/m2 and m2/m2 genotypes of the I site and the Ile/Val genotype were, however, slightly over-represented in squamous cell carcinoma patients. Among patients with squamous cell carcinoma diagnosed before 66 years of age the m1/m2 genotype was found in 28% (10/36), whereas the same genotype was observed in 16% (52/329) of healthy control subjects. A combined risk of squamous cell carcinoma was indicated for patients, diagnosed before 66 years of age, carrying both GSTM1(−) and m2 alleles (OR = 3.0, 95% CI = 1.2–7.2). [ABSTRACT FROM PUBLISHER]

The hearts of rats treated with dipyridamole were studied by light microscope autoradiography and measurement of tissue radioactivity after intravenous injection of 3H-thymidine. Total tissue radioactivity was significantly increased in the hearts of the dipyridamole-treated animals.Only capillary wall cells were labelled in the autoradiograms. The observations indicate a proliferation of capillary wall cells, suggesting a neoformation of myocardial capillaries during dipyridamole treatment. [ABSTRACT FROM PUBLISHER]

Interstitial lung disease (ILD) encompasses a heterogeneous group of more than 200 conditions, of which primarily idiopathic pulmonary fibrosis (IPF), idiopathic nonspecific interstitial pneumonia, hypersensitivity pneumonitis, ILD associated with autoimmune diseases and sarcoidosis may present a progressive fibrosing (PF) phenotype. Despite different aetiology and histopathological patterns, the PF-ILDs have similarities regarding disease mechanisms with self-sustaining fibrosis, which suggests that the diseases may share common pathogenetic pathways. Previous studies show an enhanced activation of serotonergic signaling in pulmonary fibrosis, and the serotonin (5-HT)2 receptors have been implicated to have important roles in observed profibrotic actions. Our research findings in support by others, demonstrate antifibrotic effects with 5-HT2B receptor antagonists, alleviating several key events common for the fibrotic diseases such as myofibroblast differentiation and connective tissue deposition. In this review, we will address the potential role of 5-HT and in particular the 5-HT2B receptors in three PF-ILDs: ILD associated with systemic sclerosis (SSc-ILD), ILD associated with rheumatoid arthritis (RA-ILD) and IPF. Highlighting the converging pathways in these diseases discloses the 5-HT2B receptor as a potential disease target for PF-ILDs, which today have an urgent unmet need for therapeutic strategies. [ABSTRACT FROM AUTHOR]