Abstract: BACKGROUND: Smoking and smoking cessation are considered to be associated with weight changes. We have recently shown that smoking acutely increases plasma levels of ghrelin, a known orexigenic hormone. Obestatin is a peptide encoded by the ghrelin gene, which opposes ghrelin effects on food intake. We conducted a study in adult volunteers measuring plasma levels of obestatin immediately after initiation of smoking. METHODS: 31 volunteers (mean age 32.2 +/- 9.2 years and mean BMI 25.7 +/- 4.1), 17 smokers and 14 non-smokers, were enrolled in our study. The 2 groups were matched in age and BMI. Plasma obestatin concentrations were determined at baseline (T0), 2 (T2), 5 (T5), 15 (T15), and 60 (T60) minutes after the initiation of smoking. RESULTS: In all 31 subjects, no significant difference in the mean values of plasma obestatin levels was observed from baseline at T2, T5, T15 and T60 after initiation of smoking (overall p = 0.15). However, a trend for higher obestatin levels was noted in smokers vs non-smokers (overall p = 0.069), which was not related to the pack-years. CONCLUSION: On the contrary with ghrelin's response after smoking initiation, there is no such an acute response of plasma obestatin levels.
Abstract: OBJECTIVE: To evaluate the diagnostic accuracy of 2 threshold values (105 breaths per minute [bpm]/L and 130 bpm/L) of the rapid shallow breathing index (RSBI) to predict a successful weaning trial outcome in a homogenous group of patients with chronic obstructive pulmonary disease (COPD). METHODS: A consecutive population of patients with COPD who were intubated for hypercapnic respiratory failure during a 2-year period were studied prospectively. RSBI was measured by 2 investigators at minute 5 of the T-piece trial, whereas 2 other physicians evaluated the 30 minute T-piece trial as successful or unsuccessful, according to clinical criteria. RESULTS: Of 64 patients with COPD (53 male, 11 female) who constituted the study population, 42 patients (35 male, 7 female; aged 70 +/- 9.2 years) completed the spontaneous breathing trial (SBT) and remained clinically stable (group 1). The remaining 22 patients (18 male, 4 female; aged 71.9 +/- 4.7 years) had to return to ventilatory support by the end of the SBT because of clinical deterioration (group 2). The 2 threshold values that were evaluated had low specificity (38.1% for < 105 bpm/L and 66.7% for < 130 bpm/L), low sensitivity (63.6% for < 105 bpm/L and 54.5% for < 130 bpm/L), and low diagnostic accuracy (46.8% for < 105 bpm/L and 65.6% for < 130 bpm/L) in predicting a successful T-piece trial outcome. CONCLUSION: RSBI measured early during an SBT cannot accurately predict the successful outcome of a T-piece trial in a homogenous population of patients with COPD.
Abstract: BACKGROUND AND AIM: The frequency of obstructive sleep apnea-hypopnea syndrome (OSAHS) in patients with idiopathic pulmonary fibrosis (IPF) remains controversial. The aim of this study was to assess the frequency of OSAHS in newly diagnosed IPF patients and to identify possible correlations with body mass index and pulmonary function testing parameters. MATERIALS AND METHODS: Thirty-four newly diagnosed IPF patients were included. All subjects underwent attended overnight PSG. None of the included subjects was under any of the currently available IPF treatments or nocturnal supplemental oxygen therapy. RESULTS: Total apnea-hypopnea index (AHI) was <5, 5-15, and >/=15/h of sleep in 14 (41%), 15 (44%), and five patients (15%), respectively. REM AHI was statistically significant correlated with TLC [Total lung capacity] (p = 0.03, r = -0.38). Diffusing capacity of the lung for carbon monoxide was correlated with mean oxygen saturation during sleep (p = 0.02, r = 0.39). CONCLUSIONS: Sleep-disordered breathing seems frequent, although remains usually under diagnosed in IPF patients. A decrease in TLC, reflecting the severity of pulmonary restriction, might predispose IPF patients in SDB, especially during the vulnerable REM sleep period.
Abstract: There were no data about the extent of azithromycin penetration into the empyemic pleural fluid in humans and in experimental animals. An empyema was created via the intrapleural injection of an Escherichia coli solution into the pleural space of New Zealand white rabbits. After an empyema was verified by thoracocentesis, 24h post inoculation, azithromycin (15 mg/kg) was administered intravenously. Antibiotic levels were determined in samples of pleural fluid and blood serum, collected serially at 2, 8, 24, 48 and 72 h, after administration. Azithromycin levels were estimated using an HPLC analytical method with fluorimetric detection. Azithromycin penetrated well into the empyemic pleural fluid, exhibiting a slower onset and decline compared to the corresponding blood serum levels. Equilibration between pleural fluid and blood serum compartments seemed to occur at 2h, with peak pleural fluid levels (C(maxpf) of 0.48 microg/ml) occurring 24h post administration and decreasing thereafter. Azithromycin peak serum concentration (C(maxserum) of 0.24 microg/ml) was observed 2h after administration and, thereafter, serum antibiotic levels remained lower than the corresponding pleural fluid ones. The area under the concentration versus time curve (AUC) and terminal half-life (T(1/2)) of azithromycin was three- to six fold and twofold higher, respectively, in the pleural fluid compared to the blood serum compartment. After intravenous administration, azithromycin penetrated well into the empyemic pleural fluid, exhibiting pleural fluid levels that are inhibitory for most erythromycin-sensitive pathogens causing empyema.
Abstract: We present a patient with Lady Windermere syndrome after coronary bypass operation. To avoid the sternal pain that occurred after every cough episode, this patient used to receive large doses of antitussive drugs. In a poorly drained lung, this usage leads to the development of regions of colonization with Mycobacterium avium complex. It is concerning that the lack of diagnosis for 18 months in this patient occurred because of the insidious symptoms that mimic bronchitis. This case emphasizes how important it is for patients after a median sternotomy to receive adequate analgesic and physiotherapeutic support in order to avoid chronic inflammation and infection of the lungs.
Abstract: ABSTRACT: OBJECTIVE: To determine the extent of linezolid and ertapenem penetration into the empyemic fluid using a rabbit model of empyema. METHODS: An empyema was created via the intrapleural injection of Escherichia coli bacteria (ATCC 35218) into the pleural space of New Zealand white rabbits. After an empyema was verified by thoracocentesis, 24 hours post inoculation, linezolid (10 mg/kg) and ertapenem (60 mg/kg) were administered intravenously into 10 and 8 infected empyemic rabbits, respectively. Antibiotic levels were determined in samples of pleural fluid and blood serum, collected serially at 1, 2, 4, 6 and 8 hours, after administration each of the two antibiotics. RESULTS: Linezolid as well as ertapenem penetrate well into the empyemic pleural fluid, exhibiting a slower onset and decline compared to the corresponding blood serum levels. Equilibration between blood serum and pleural fluid compartments seems to occur at 1.5 hours for both linezolid and ertapenem, with peak pleural fluid levels (Cmaxpf of 2.02 +/- 0.73 <<mu>>g/ml and Cmaxpf of 3.74 +/- 1.39 <<mu>>g/ml, correspondingly) occurring 2 hours post antibiotics administration and decreasing very slowly thereafter. The serum concentrations for both antibiotics were significantly lower from the corresponding pleural fluid ones during the 8 hours collecting data, with the exception of samples collected at the 1st hour (Cmaxserum of 2.1 +/- 1.2 <<mu>>g/ml for linezolid and Cmaxserum of 6.26 +/- 2.98 <<mu>>g/ml for ertapenem). CONCLUSION: Pleural fluid levels of both antibiotics are inhibitory for common specified pathogens causing empyema.
Abstract: ABSTRACT: INTRODUCTION: There are few reported cases of neutrophilic pleural effusions associated with valproic acid therapy. Most of them are of eosinophilic exudates with or without blood eosinophilia. CASE PRESENTATION: This case study describes a 70-year-old man with recurrent episodes of eosinophilic transudative pleural effusions associated with sodium valproate treatment. The recurrence of effusion after re-administration of the drug is strongly suggestive of an association between them. To the best of our knowledge, this is the first reported case with a pleural effusion with these characteristics caused by sodium valproate. CONCLUSION: This is the first report in the literature, with a full understanding of the etiology but with an unknown drug mechanism. This case report is of interest to different medical specialists (such as pulmonologists, neurologists, cardiologists) and pharmacologists.
Abstract: BACKGROUND: Several studies assessing the role of obstructive sleep apnea syndrome (OSAS) as an independent risk factor for hypertension have produced conflicting results. Although the sleep apnea syndrome is associated with hypertension, there are no references regarding the blood pressure response of normotensive OSAS patients during exercise. STUDY OBJECTIVES: The aim of this study was to investigate the relationship between diastolic blood pressure (DBP) response during exercise and the severity of OSAS. METHODS: We performed exercise testing a day after polysomnography in 17 normotensive males who were admitted for the first time because of OSAS and in 10 normal subjects who were members of the same families. During maximal incremental exercise test (bicycle ergometry) oxygen consumption (VO(2)) and the DBP were estimated at rest and at peak exercise. VO(2) was also measured when DBP were 100 and 110 mm Hg. RESULTS: At peak exercise DBP was significantly higher in OSAS patients (115.3 +/- 9.2 mm Hg) than in normal subjects (101 +/- 8.4 mm Hg, p < 0.01). OSAS patients reached a DBP of 110 mm Hg with a significantly lower VO(2) than normal subjects (1,881.5 +/- 703.4 vs. 1,972.3 +/- 108.6 ml/min, p = 0.045). VO(2) was not different between the two groups at a DBP of 100 mm Hg (1,211.2 +/- 371.7 vs. 1,536.6 +/- 267.2 ml/min, p = 0.089) but OSAS patients had a significantly lower heart rate than normals (111.2 +/- 13 vs. 118.6 +/- 27.6, p = 0.009). None of the aspects of quality of life, according to the Nottingham Health Profile Questionnaire, Part 1, were significantly different between patients and normal subjects. CONCLUSIONS: Normotensive OSAS patients develop DBP elevation at an earlier stage during exercise compared to normal subjects. This hypertensive response was not correlated with the severity (apnea-hypopnea index, oxygen desaturation parameters) of OSAS. DBP elevation could be a limiting factor of physical performance in this group of patients.
Abstract: PURPOSE: To investigate possible effects of sildenafil on the cardiopulmonary responses during sexual intercourse we evaluated cardiopulmonary responses during exercise in a group of impotent patients. MATERIALS AND METHODS: The study sample included patients with erectile dysfunction who underwent a cardiopulmonary exercise test before and after the administration of 100 mg. sildenafil citrate. Cardiopulmonary exercise test parameters at rest, at the anaerobic threshold, at peak exercise and at 1-minute recovery were recorded, including systolic and diastolic blood pressure, the heart rate, O2 consumption, CO2 production, ventilation and the respiratory rate. Furthermore, O2 consumption per kg. body weight, the ventilatory equivalent for O2 consumption (ventilation/O2 consumption) and CO2 production (ventilation/CO2 production), the respiratory quotient, metabolic equivalents metabolic equivalents, oxygen pulse (O2 consumption/heart rate) and the change in O2 consumption/change in heart rate were calculated. RESULTS: In 2 of the 43 patients enrolled in the study myocardial ischemia and high blood pressure were detected at rest in 2, respectively, who were excluded from analysis. In the remaining 41 patients with a mean age +/- SD of 52.3 +/- 8.6 years a statistically significant decrease in systolic and diastolic blood pressure was noted after sildenafil use at all stages tested (p <0.002 to 0.001). The heart rate mildly increased after sildenafil use at rest and at peak exercise (p = 0.018). The O2 pulse decreased at the anaerobic threshold (p = 0.003), peak exercise (p = 0.001) and recovery (p = 0.047). In the 11 patients with a mean age of 40.8 +/- 10.12 years who had psychogenic erectile dysfunction the only 2 parameters affected were an increased heart rate and decreased systolic blood pressure at rest, while O2 consumption/heart rate decreased at the anaerobic threshold. In the 18 patients with a mean age of 61.1 +/- 8.9 years who had organic erectile dysfunction and an unremarkable medical history a decrease was noted in systolic and diastolic blood pressure at rest and at peak exercise, and diastolic blood pressure also at recovery, while the heart rate increased at recovery. In the 12 patients with a mean age of 60.16 +/- 9.12 years who had treated cardiovascular disease systolic and diastolic blood pressure decreased at all states and O2 consumption/heart rate at the anaerobic threshold and at peak exercise, while increased values were noted for the respiratory rate at the anaerobic threshold and ventilation/CO2 production at recovery. CONCLUSIONS: Hemodynamic changes after sildenafil administration should be considered minimal in concert with patient health status. Younger patients without signs of systemic atherosclerosis compensate the vasodilatory effect of sildenafil during exercise, while in older patients with vasculogenic erectile dysfunction moderate changes may be noted regardless of cardiovascular disease in the medical history.
Abstract: 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 N(2) washout method. Mean (Te(mean)) and maximal expiratory time (Te(max)) 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 Te(occ) than Te(max) (Te(occ)/Te(max), %). Occlusion was maintained until negative airway pressure occurred and the occlusion time (Te(occ)) 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 H(2)O PEEP. Te(occ) 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 Te(occ)/Te(max). RESULTS: The ratio Te(occ)/Te(max) increased from 167.5 +/- 82.5 at normal FRC to 474 +/- 200.2 s (PEEP(20)). On the contrary, in patients with COPD, Te(occ)/Te(max) 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.
