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Background: Eosinophilic lung diseases comprise a group of heterogeneous pulmonary disorders linked by increased eosinophils in bronchoalveolar lavage fluid (BALF). There is supporting evidence that natural killer (NK) cells participate in the regulation of eosinophilic inflammation. Objective: Our aim was to investigate the relationship between eosinophils and NK cells in BALF in patients with different interstitial lung diseases (ILDs) focusing on eosinophilic pneumonias. Methods: Of 114 patients who presented with increased BALF eosinophils (>5%), 74 patients were classified into the following groups: 27 had eosinophilic pneumonia (EP), 17 had idiopathic pulmonary fibrosis (IPF), 16 had hypersensitivity pneumonitis (HSP) and 14 had cryptogenic organizing pneumonia (COP/BOOP). Total BALF cells, cell density and cell differential counts were assessed and lymphocyte subsets CD3+, CD4+, CD8+, CD19+, CD3–CD16/56+ (NK) and CD3+CD16/56+ (NKT) were determined by flow cytometry. Results: Significant differences were observed in the percentages of lymphocytes (p < 0.001) and CD3+CD16/56+ cells (p = 0.023) among patient groups. In patients with EP, the percentage of eosinophils correlated positively with the number of CD3–CD16/56+ cells (r = 0.522, p = 0.005), the percentage of CD3–CD16/56+ cells (r = 0.690, p < 0.001), and the absolute count of CD3+CD16/56+ absolute cells (r = 0.609, p = 0.001). However, in patients with IPF, HSP or COP/BOOP, no correlation between the percentage of eosinophils and CD3–CD16/56+ or CD3+CD16/56+ cells was observed. Conclusions: Eosinophil inflammation seems to develop through a different pathway in EP compared to other ILDs.

Background: Asbestos exposure is related to serious adverse health effects. However, there is disagreement about the relationship between chrysotile exposure and mesothelioma or lung cancer. Objectives: Our aim was to investigate the mortality rate among workers exposed to relatively pure chrysotile in an asbestos cement factory. Patients and Methods: In an asbestos cement plant opened in 1968, we prospectively studied all 317 workers. A quantity of 2,000 tons of chrysotile, with minimal amphibole contamination, was used annually until 1 January 2005. Asbestos fiber concentration was measured regularly. Date and cause of death were recorded among active and retired workers. Results: Asbestos fiber concentration was always below permissible levels. Fifty-two workers died during the study. The cause was cancer in 28 subjects; lung cancer was diagnosed in 16 of them. No case of mesothelioma was reported. Death was attributed to cardiovascular diseases in 23 subjects and to liver cirrhosis in 1. Overall mortality rate was significantly lower than that of the Greek general population, standardized mortality ratio (SMR) was 0.71 (95% CI 0.53–0.93). Mortality due to cancer was increased (SMR 1.15, 95% CI 0.77–1.67), mainly due to lung cancer mortality (SMR 1.71, 95% CI 0.98–2.78), but not significantly. Conclusions: Occupational exposure to relatively pure chrysotile within permissible levels was not associated with a significant increase in lung cancer or with mesothelioma. Decreased overall mortality of workers indicates a healthy worker effect, which – together with the relatively small cohort size – could have prevented small risks to be detected.

Background: Expiratory flow limitation (EFL) is one of the main mechanisms contributing to dyspnea in patients with chronic obstructive pulmonary disease but has not been explored in patients with pleural effusion. Objectives: It was the aim of this study to determine whether patients with pleural effusion exhibit EFL and to investigate the effect of therapeutic thoracentesis on EFL. Patients and Methods: The study was performed on 21 patients with pleural effusion who were subjected to thoracentesis and measurement of pleural pressure (PP). Spirometry and estimation of flow limitation by the negative expiratory pressure technique were performed before and after thoracentesis. Results: Statistically significant differences were observed in all spirometric parameters. No correlation between the increase in lung volumes and flows and any of the aspirated fluid parameters was observed. Before thoracentesis, 14 out of 21 patients were flow limited, compared with 7 patients after thoracentesis (χ2 = 6.151, p = 0.013). Mean values of flow limitation before and after thoracentesis differed significantly. The decrease in flow limitation did not correlate with the increase in the spirometric parameters, the aspirated fluid volume or PP decrease. Conclusions: In the majority of patients with pleural effusion, flow limitation improves after thoracentesis. Flow limitation may be a contributing factor to the sensation of dyspnea in these patients.

Background: It has been suggested that the Hering-Breuer reflex (HBR) is unimportant in adults during normal tidal breathing and that it is elicited only if tidal volume is increased above a certain critical threshold. Objective: The aim of this study was (1) to study the occurrence of the HBR in adults with normal pulmonary function and (2) to examine if changes in lung mechanics have any effect on the HBR. Methods: We examined 11 adults with normal pulmonary function, 8 patients with chronic destructive pulmonary disease (COPD) and 3 with interstitial fibrosis (IF). All subjects were lightly sedated with fentanyl, intubated and ventilated with a Servo-900 ventilator. Inspiratory and expiratory flow (and after integration, volume) and mouth pressure were recorded from the endotracheal tube with a pneumotachograph and a pressure transducer. Pressure support ventilation was applied in all patients and functional residual capacity (FRC) was measured with the N2 washout method. Mean (Temean) and maximal expiratory time (Temax) were determined for each individual for 20 breaths. Following several breaths to establish a stable baseline the airway was occluded at end inspiration by a shutter. A positive HBR was interpreted as longer Teocc than Temax (Teocc/Temax, %). Occlusion was maintained until negative airway pressure occurred and the occlusion time (Teocc) was measured. We attempted occlusions after the addition of 5 cm H2O positive end-expiratory pressure (PEEP) and subsequently with 10, 15 and 20 cm H2O PEEP. Teocc was measured of progressively larger lung volumes. To examine the HBR sensitivity in the three groups, we plotted the lung volumes of occlusion against the corresponding Teocc/Temax. Results: The ratio Teocc/Temax increased from 167.5 ± 82.5 at normal FRC to 474 ± 200.2 s (PEEP20). On the contrary, in patients with COPD, Teocc/Temax increased from 125.2 ± 34 to 193.7 ± 74.2 (p < 0.05). Conclusions: The HBR was positive in all subjects. COPD patients were found to be less sensitive to volume changes when compared with normal controls and with IF patients.

Buspirone is an anxiolytic agent that appears to have no sedative effects. The aim of this study was to assess the effects of buspirone on breathlessness and exercise tolerance in patients with chronic airway obstruction. Sixteen patients, age 56.9 +/- 17.0; forced expiratory volume in 1 s (FEV1) 1.15 +/- 0.42 l; FEV1/forced vital capacity (FVC) 50.7 +/- 15.0%; PaCO2 42.2 +/- 5.5 mm Hg; and PaO2 57.6 +/- 10 mm Hg, underwent a 6-min walking test, an incremental cycle ergometer test, an incremental treadmill walking test with self-assessment of dyspnea on Borg's scale during exercise and an assessment of respiratory drive (P 0.1), timing [inspiration time (TI)/total breathing time (Ttot)], PaO2, PaCO2, FVC, FEV1, following oral administration for 14 days of placebo or buspirone (20 mg daily) in a double-blind, cross-over randomized way. We also used the symptom check list-90-R for the assessment of subjective complaints and symptomatic behavior. A significant improvement in anxiety, depression and obsessive symptoms and complaints was noted after buspirone treatment. The P 0.1, TI/Ttot, arterial blood gases and respiratory mechanics did not change after drug treatment. There was an improvement in exercise tolerance and in the sensation of dyspnea during the buspirone period. Thus, as given in this study, oral buspirone has therapeutic potential in the treatment of dyspnea in patients with chronic lung disease.

Respiratory drive in a patient with central alveolar hypoventilation was assessed by mouth occlusion pressure method. Respiratory drive was almost abolished in this patient.