Clearance of technetium-99m-DTPA in pulmonary sarcoidosis

Background. The aim of this study was to explore the possible association of the lung clearance of 99mTc- DTPA scan with HRCT lung abnormalities and with the pulmonary function tests [PFTs] in patients with sarcoidosis. Methods. We studied prospectively 15 patients [5 males, 10 females] of median age 46yr [range 27-67] with histologically proved sarcoidosis. HRCT scoring included the sum of the severity and extent of lymph node enlargement and parenchymal involvement. Results. The mean DTPA clearance half-time [Ï„ 1/2 <40 min] was found [mean [SD]] 38.3+4.5min. The lymph node enlargement was found 34% and the parenchymal involvement 12%. DTPA clearance was negatively correlated with the parenchymal involvement [r= -0.651, p=0.009]. The HRCT parenchymal abnormalities were found significantly correlated with PFTs [FVC [r= -0.65, p=0.008] and TLCO [r= -0.76, p=0.02]. Conclusions. Our data suggest a moderate association between 99mTc-DTPA scan and HRCT in pulmonary sarcoidosis. However, further studies in large scale of sarcoid patients are needed to clarify the role of this novel methodology in the evaluation and follow-up of this disorder.

Stability of phenotypes defined by physiological variables and biomarkers in adults with asthma

BACKGROUND

Although asthma is characterized by variable airways obstruction, most studies of asthma phenotypes are cross-sectional. The stability of phenotypes defined either by biomarkers or by physiological variables was assessed by repeated measures over 1 year in the Pan-European BIOAIR cohort of adult asthmatics.

METHODS

A total of 169 patients, 93 with severe asthma (SA) and 76 with mild-to-moderate asthma (MA), were examined at six or more visits during 1 year. Asthma phenotype clusters were defined by physiological variables (lung function, reversibility and age of onset of the disease) or by biomarkers (eosinophils and neutrophils in induced sputum).

RESULTS

After 1 year of follow-up, the allocation to clusters was changed in 23.6% of all asthma patients when defined by physiological phenotypes and, remarkably, in 42.3% of the patients when stratified according to sputum cellularity (P = 0.034). In the SA cohort, 30% and 48.6% of the patients changed allocation according to physiological and biomarker clustering, respectively. Variability of phenotypes was not influenced by change in oral or inhaled corticosteroid dose, nor by the number of exacerbations. Lower stability of single and repeated measure was found for all evaluated biomarkers (eosinophils, neutrophils and FeNO) in contrast to good stability of physiological variables (FEV1 ), quality of life and asthma control.

CONCLUSION

Phenotypes determined by biomarkers are less stable than those defined by physiological variables, especially in severe asthmatics. The data also imply that definition of asthma phenotypes is improved by repeated measures to account for fluctuations in lung function, biomarkers and asthma control.

Differential telomerase expression in idiopathic pulmonary fibrosis and non-small cell lung cancer

Telomerase is a reverse transcriptase ribonucleo-protein (h-TERT) that synthesizes telomeric repeats using its RNA component (h-TERC) as a template. Telomerase dysfunction has been associated with both fibrogenesis and carcinogenesis. In this study, we aimed to evaluate the telomerase mRNA expression levels of both subunits (h-TERT and h-TERC) in lung tissue and bronchoalveolar lavage fluid (BALF) from patients with idiopathic pulmonary fibrosis (IPF) and non-small cell lung cancer (NSCLC), since there are indications of common pathogenetic pathways in these diseases. We prospectively examined lung tissue samples from 29 patients with IPF, 10 patients with NSCLC and 21 controls. Furthermore, we examined BALF samples from 31 patients with NSCLC, 23 patients with IPF and 12 control subjects. The mRNA expression for both h-TERT and h-TERC was measured by real-time RT-PCR. In the lung tissue samples, both h-TERT and h-TERC mRNA expression levels varied among the 3 groups (p=0.036 and p=0.002, respectively). h-TERT mRNA levels in the patients with IPF were lower compared with those in the controls (p=0.009) and patients with NSCLC (p=0.004). h-TERC mRNA levels in the patients with IPF were lower compared with those in the controls (p=0.0005) and patients with NSCLC (p=0.0004). In the BALF samples, h-TERT mRNA expression levels varied among the groups (p=0.012). More specifically, h-TERT mRNA levels in the patients with IPF were higher compared with those in the controls (p=0.03) and patients with NSCLC (p=0.007). The attenuation of telomerase gene expression in IPF in comparison to lung cancer suggests a differential role of this regulatory gene in fibrogenesis and carcinogenesis. Further functional studies are required in order to further elucidate the role of telomerase in these devastating diseases.

An update on idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressively fibrotic disease with a median survival of 3-5 years. Despite recent advances the pathophysiology of the disease remains not fully understood. However, injury of type II alveolar epithelial cells is considered the key event for the initiation of the development of fibrosis. An accurate diagnosis is imperative because commencing treatment at an early stage may reduce disease progression. In this regard, the multidisciplinary disease meeting between pulmonologists, radiologists and pathologists has definitely improved the diagnostic confidence. Importantly, a milestone has been recently reached as the first IPF-specific drug namely pirfenidone has been licensed in Europe, Japan and Asia.

The small airways and distal lung compartment in asthma and COPD: a time for reappraisal

The involvement of small airways in the pathogenesis of asthma and chronic obstructive pulmonary disease (COPD) has been debated for a long time. However, a proper definition of small airway disease is still lacking, and neither a widely accepted biomarker nor a functional parameter to assess small airway abnormalities and to explore the effect of tested compounds on small airways is available. Aiming towards increased knowledge and consensus on this topic, this perspective paper intends to (i) strengthen awareness among the scientific community on the role of small airways in asthma and COPD; (ii) examine the pros and cons of some biological, functional and imaging parameters in the assessment of small airway abnormalities; and (iii) discuss the evidence for distal airway pharmacological targeting in asthma and COPD.

A hypothesis for the initiation of COPD

Chronic obstructive pulmonary disease (COPD) is generally thought to depend on an aberrant immune response to a noxious or infectious agent, which may cause chronic inflammation. However, the initiation of this abnormal response is not fully understood. Here, we propose a new hypothesis for the beginning of COPD, that the immune response to inhaled agents, mainly cigarette smoke, is directed toward the airway epithelium, due to oxidative DNA damage of the lung epithelial barrier cells (LEBCs). The steps of this model are as follows. 1) Cigarette smoke induces oxidative DNA damage of LEBCs. 2) The acquired mutations are expressed at the microsatellite DNA level of LEBCs. 3) The altered LEBCs are recognised by dendritic cells (DCs) as "nonself". DCs travel, with the new information, to the lymph nodes, presenting it to the naïve T-lymphocytes. 4) A predominant CD8+ cytotoxic T-lymphocyte proliferation occurs. The CD8+ cells, by releasing perforin and granzymes, attack the altered LEBCs activating cell death cascades. Obviously, the above scenario needs further experimental exploration. However, it is an attractive model for the initiation of the abnormal inflammation in COPD, comprising oxidative DNA damage of LEBCs and host immune response.

Increased bronchoalveolar lavage fluid CD1c expressing dendritic cells in idiopathic pulmonary fibrosis

BACKGROUND

Chronic inflammation is implicated in idiopathic pulmonary fibrosis (IPF) pathogenesis and is associated with persistent activation of immune responses. These are largely controlled by dendritic cells (DCs). Although large numbers of DCs infiltrate the lungs of patients with IPF, there are no similar reports in bronchoalveolar lavage fluid (BALF).

OBJECTIVES

We aimed to investigate DC populations in BALF of IPF patients.

METHODS

CD1c(+) myeloid DCs, BDCA3(high) myeloid DCs, BDCA2(+) plasmacytoid DCs and CD83(+) mature DCs were identified by flow cytometry in the BALF of 10 IPF patients and 10 controls. DC numbers were expressed as percentages of total BALF leukocytes.

RESULTS

CD1c(+) myeloid DCs were increased in IPF patients versus controls [median (ranges in parentheses) 1.16% (0.25-3.97) vs. 0.61% (0.19-1.10), p = 0.01]. There was also a trend towards increased BDCA3(high) myeloid DCs [0.57% (0.23-0.88) vs. 0.28% (0.07-0.96), p = 0.07]. No differences were reported in BDCA2(+) DCs and CD83(+) DCs between IPF patients and controls.

CONCLUSIONS

IPF is associated with an increase in percentages of BALF myeloid DCs. Considering that such an increase was not observed in CD83(+) mature DCs, most of these DCs should be immature.

Microsatellite DNA analysis does not distinguish malignant from benign pleural effusions

Distinguishing malignant from benign pleural effusions using routine cytology is a common diagnostic problem. Recently, genetic alterations, including microsatellite instability (MSI) and loss of heterozygosity (LOH), have been described in malignant pleural effusions and proposed as methods improving diagnostics. The purpose of this study was to evaluate a panel of molecular markers for the detection of genetic alterations of cells in pleural effusions and to determine their diagnostic value as an additional test to cytologic examination. Pleural fluid and peripheral blood from 48 patients (36 male and 12 female, median age 71 years) were analyzed. Twenty-six patients had malignant pleural effusion, including 23 lung cancer and three metastatic non-pulmonary carcinoma. The control group consisted of 22 patients with benign pleural effusions. Only 14 malignancy-associated pleural effusions were cytology-positive for malignant cells (54%), whereas all benign pleural effusions were negative. DNA was extracted from all the samples and analysed for MSI and/or LOH using the following microsatellite markers: D3S1234, D9S171, D12S363, D17S250, D5S346 and TP53Alu, located at five chromosomal regions: 3p, 9p, 12q, 17q, 5q. Microsatellite analysis of the pleural fluid pellet exhibited genetic alterations in two neoplastic pleural fluid cases and in one inflammatory case. Two out of 26 (7.6%) patients with malignant pleural effusion showed genetic alterations. One exhibited MSI in three different microsatellite markers (D17S250, D9S171, D3S134) and the other showed LOH in marker D3S134. One out of 22 (4.5%) patients with benign pleural effusion showed LOH in marker D3S134. In conclusion, genetic alterations at the level of microsatellite DNA, were detected only in very few cases of malignant pleural effusions, and in one case of benign pleural effusion. Thus, our data suggest that microsatellite DNA analysis does not facilitate the diagnosis of malignant pleural effusion.

Effect of voluntary respiratory efforts on breath-holding time

INTRODUCTION

Near the end of a maximal voluntary breath-hold, re-inhalation of the expired gas allows an additional period of breath-holding, indicating that the breaking point does not depend solely on chemical drive. We hypothesized that afferents from respiratory muscle and/or chest wall are significant in breath-holding.

METHODS

Nineteen normal adults breathed room air through a mouthpiece connected to a pneumotachograph and were instructed to breath-hold with and without voluntary regular respiratory efforts against an occluded airway.

RESULTS

Fifty one trials with and 53 without respiratory efforts were analyzed. The mean number of efforts per minute was 19+/-2.3 and the mean lowest airway pressure (P(aw)) -16.6+/-5.4 cmH(2)O. Breath-holding time (BHT) did not differ without (33.0+/-18.2 s) and with (29.3+/-12.3 s) efforts. In five patients arterial blood gasses were measured before and at the end of breath-holding and they did not differ between trials without and with efforts, indicating similar chemical drive. Our results suggest that afferents from respiratory muscle and/or chest wall are not the major determinants of BHT.

Exacerbations and lung function decline in COPD: New insights in current and ex-smokers

AIM

To investigate whether there is a significant relationship between an increased frequency of exacerbations and the rate of forced expiratory volume in 1s (FEV(1)) decline in COPD patients. METHODS-MEASUREMENTS: About 102 COPD patients (44 smokers, 58 ex-smokers) participated in a 3-year prospective study. Exacerbations were identified as worsening of patient's respiratory symptoms as recorded on diary cards. Spirometry was performed every 6 months. The effect of frequent exacerbations on lung function was investigated using random effects models.

RESULTS

The median (mean(95% CI)) annual exacerbation rate was 2.85 (3.1 (2.7-3.6)). Patients with an annual exacerbation rate over the median rate had significantly lower baseline post-bronchodilation FEV(1)(%pred), higher MRC dyspnoea score and chronic cough compared to patients who had an annual exacerbation rate less than the median. The average annual rate of FEV(1)(%pred), adjusted for smoking decline (DeltaFEV(1)), was found significantly increased in frequent compared to infrequent exacerbators (P=0.017). The highest DeltaFEV(1) was observed in smokers frequent exacerbators and a significant interaction between exacerbation frequency and DeltaFEV(1) was also observed in ex-smokers.

CONCLUSIONS

Our findings suggest that an increased frequency of exacerbations is significantly associated with FEV(1) decline even in ex-smokers. Thus, smoking and frequent exacerbations may have both negative impact on lung function. Smoking cessation and prevention of exacerbations should be a major target in COPD.

Pharmacological approaches to smoking cessation

Smoking, the most prominent nongenetic factor contributing to mortality, remains the major public health problem throughout the world. There are nearly 1.1 billion users of nicotine and tobacco products worldwide while approximately one third to half of them will die from smoking-related disease. The habit of smoking is mainly propelled by nicotine, a strongly addictive substance, to which the vast majority of smokers fall victim. Except for the general and specific support and counseling strategies there are now effective treatments for nicotine addiction. Two types of pharmacological therapies have been approved and are now licensed for smoking cessation. The first therapy consists of nicotine replacement, substituting the nicotine from cigarettes with safer nicotine formulations. The second therapy is bupropion, an antidepressant of the aminoketone class, which has been demonstrated to be effective in smoking cessation. However, although some cigarette smokers are able to quit, many are not, and standard medications to assist smoking cessation are ineffective. Several agents used for other indications (e.g. neurological diseases, depression, alcoholism) might be used to treat this subgroup. In conclusion, new more effective drugs are needed in order to fight the panepidemic of smoking globally.

Near-fatal asthma phenotype in the ENFUMOSA Cohort

BACKGROUND

Near-fatal asthma (NFA) is characterized by severe asthma attacks usually requiring intensive care unit admission. This phenotype of asthma has been studied mainly in acute conditions.

METHODS

The aim of our study was to compare the clinical, functional and inflammatory characteristics of NFA patients with mild to severe asthmatics in stable conditions. We recruited 155 asthmatic patients from five centres of the European Network for Understanding Mechanisms of Severe Asthma: 67 patients with mild-to-moderate asthma controlled by low/medium doses of inhaled corticosteroids; 64 with severe asthma that, despite treatment with high doses of inhaled corticosteroids, long-acting beta2-agonists and for 1/3 also with regular oral corticosteroids, had at least one asthma exacerbation in the previous year; 24 with an NFA episode in the previous 5 years in the absence of inclusion criteria for the previous groups. All the patients were examined in stable conditions.

RESULTS

NFA patients were taking less corticosteroids and were less compliant to prescribed asthma medications than the other two groups of patients. Lung function, blood gases, atopic status, sputum and blood inflammatory cell count of NFA patients were similar to mild-to-moderate, but not severe, asthmatic patients.

CONCLUSIONS

In stable conditions patients with an NFA attack in the previous 5 years cannot be distinguished from patients with mild-to-moderate asthma, while they are different from severe asthmatics both in terms of lung function and of airway inflammation. The risk factor that characterizes this group of patients is reduced usage of prophylactic corticosteroids.

Infliximab therapy in pulmonary fibrosis associated with collagen vascular disease

OBJECTIVE

To study the potential effectiveness of tumor necrosis factor a (TNF-alpha) inhibitor treatment for pulmonary fibrosis associated with a collagen vascular disease, CVD (rheumatoid arthritis, RA and systemic sclerosis, SSc) refractory to conventional treatment.

METHODS

Four patients (three men with RA, one woman with SSc) were treated with infliximab. All patients received 3mg/kgr of infliximab at intervals 0, 2 and 6 weeks, and then maintenance infusions every 8 weeks afterwards for at least a 12-month period. Patients had active disease despite treatment with corticosteroids and other immunomodulatory agents.

RESULTS

Treatment was well-tolerated from all patients. Pulmonary fibrosis remained stable during treatment in terms of symptoms, pulmonary function tests (PFTs) and High resolution computed tomography (HRCT) appearance. As expected, a clinical response was observed in joint symptoms in patients with RA as evaluated by the DAS28 (Disease Activity Score, the 28 joint version).

CONCLUSION

This study suggests that inhibition of TNF-alpha with infliximab may stabilize the progression of pulmonary fibrosis associated with CVD. Prospective, controlled trials are necessary to determine the efficacy of infliximab in pulmonary fibrosis associated CVD.

Differences in microsatellite DNA level between asthma and chronic obstructive pulmonary disease

Previous studies have shown that microsatellite (MS) DNA instability (MSI) is detectable in sputum cells in chronic obstructive pulmonary disease (COPD) and asthma. The aim of the present study was to investigate whether asthma and COPD could be distinguished at the MS DNA level. DNA was extracted from sputum cells and white blood cells from 63 COPD patients, 60 non-COPD smokers, 36 asthmatics and 30 healthy nonsmokers. Ten MS markers located on chromosomes 2p, 5q, 6p, 10q, 13q, 14q and 17q were analysed. No MSI was detected in non-COPD smokers or healthy nonsmokers. A significantly higher proportion of COPD patients exhibited MSI (49.2%) compared to asthmatics (22.2%). MSI was detected even in the mild stages of COPD (33.3%) and asthma (22.2%). No relationship was found between MSI and COPD severity. The most frequently affected marker was D14S588 (17.5% in COPD and 2.7% in asthma). The markers D6S344, G29802 and D13S71 showed alterations only in COPD, and G29802 was associated with a significantly decreased forced expiratory volume in one second FEV1 (% predicted), whereas MSI in D6S344 was associated with a significantly higher FEV1 (% pred). The frequency of microsatellite instability was higher in chronic obstructive pulmonary disease than in asthma, and microsatellite instability in three workers showed chronic obstructive pulmonary disease specificity. However, further studies are needed to verify the differences between chronic obstructive pulmonary disease and asthma at the microsatellite level.

Exhaled markers of oxidative stress in idiopathic pulmonary fibrosis

BACKGROUND

Expired breath condensate (EBC) has never been used to explore the level of oxidative stress in idiopathic pulmonary fibrosis (IPF). Therefore, the aim of this study was to measure the levels of H2O2 and 8-isoprostane, as biomarkers of oxidative stress, in the EBC of patients with IPF.

MATERIALS AND METHODS

We investigated 16 patients with IPF and 15 healthy subjects as the control group. The levels of H2O2 and 8-isoprostane were measured in the EBC of all subjects and were compared between the IPF and control groups. In patients with IPF, H2O2 and 8-isoprostane were further correlated with pulmonary function tests (PFTs), the resting pO2 and the differential cell count from the bronchoalveolar lavage fluid (BALF).

RESULTS

The mean (95%CI) concentration of H2O2 was increased in the patients with IPF compared with the normal subjects (0.36, 0.24-0.47 microM vs. 0.16, 0.10-0.23 microM, P=0.003). The mean (95%CI) concentration of 8-isoprostane was also increased in the patients with IPF compared with the controls (74, 38-110 pg mL-1 vs. 33, 28-39 pg mL-1, P=0.02). In the patients with IPF, the diffusing capacity of the lung for carbon monoxide was negatively correlated with the levels of H2O2 in EBC (P=0.03, r=-0.58). No other correlation was found between the oxidative stress markers in the EBC and PFT values, pO2 or BALF cell count.

CONCLUSIONS

Our data suggest that H2O2 and 8-isoprostane are increased in the EBC of patients with IPF. H2O2 may be correlated with the severity of the disease in IPF.

Angiogenic molecules in Hodgkin's disease: results from sequential serum analysis

Increased angiogenic activity has been demonstrated in lymphoproliferative diseases including Hodgkin's disease. In the current study, the levels of circulating angiogenic molecules in 60 Hodgkin's patients were determined prior to and after treatment and correlated to disease stage and prognostic score. Hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) were increased in Hodgkin's patients in comparison to healthy controls (p<0.001). Angiogenin and angiopoietin-2 levels did not differ from controls. HGF, VEGF, TNF-alpha and angiogenin decreased significantly in Hodgkin's patients after standard treatment (p<0.001 for HGF, p<0.05 for VEGF, TNF-alpha and angiogenin). Furthermore, HGF and TNF-alpha increased with advancing stage of disease (p<0.05). HGF and VEGF correlated significantly with IL-6 (r=0.56, p<0.0005 and r=0.57, p<0.001 respectively). In conclusion, Hodgkin's disease displays an angiogenic activity as depicted by the increased serum levels of a number of angiogenic cytokines. HGF seems to be the prominent molecule in Hodgkin's disease, which may be used to monitor the disease status and the response to treatment.

Effects of pleural effusion on respiratory function

The accumulation of pleural effusion has important effects on respiratory system function. It changes the elastic equilibrium volumes of the lung and chest wall, resulting in a restrictive ventilatory effect, chest wall expansion and reduced efficiency of the inspiratory muscles. The magnitude of these alterations depends on the pleural fluid volume and the underlying disease of the respiratory system. The decrease in lung volume is associated with hypoxemia mainly due to an increase in right to left shunt. The drainage of pleural fluid results in an increase in lung volume that is considerably less than the amount of aspirated fluid, while hypoxemia is not readily reversible upon fluid aspiration.

Inflammatory cell profiles and T-lymphocyte subsets in chronic obstructive pulmonary disease and severe persistent asthma

BACKGROUND

Severe persistent asthma (SPA) and chronic obstructive pulmonary disease (COPD) are both associated with non-reversible airflow limitation and airway neutrophilia.

OBJECTIVE

To compare inflammatory cell profiles and T lymphocyte subsets between SPA and COPD patients with similar severity of airflow limitation.

METHODS

Sputum induction and lung function tests were performed in 15 COPD patients aged (mean+/-SD) 68+/-8 years, ex-smokers, mean forced expiratory volume in 1 s (FEV1) 45% of predicted (% pred) and 13 SPA aged 55+/-10 years, non-smokers, mean FEV(1) 49% pred. All patients were on inhaled steroid treatment. Eight asthmatics exhibited irreversible airflow limitation. Differential cell count, metachromatic cell count and double immunocytochemistry for the analysis of T lymphocyte subsets were performed on sputum slides.

RESULTS

COPD patients had increased sputum neutrophils in comparison with SPA (P<0.03), but similar to SPA with fixed obstruction. In COPD sputum neutrophils negatively correlated with the lung transfer factor for carbon monoxide (KCO) (r=-0.462, P=0.04). SPA showed significantly increased eosinophils and metachromatic cells vs. COPD patients (P<0.04, P<0.007, respectively). Increased CD4/CD8 and decreased CD4-IFN-gamma/CD4-IL4+ cell ratio (P<0.001) were found in SPA vs. COPD. In SPA, CD4/CD8+ cell ratio correlated with sputum eosinophils (r=0.567, P=0.04).

CONCLUSION

In spite of treatment with inhaled steroids, SPA and COPD exhibit distinct sputum inflammatory cell patterns, although SPA with fixed airflow limitation and COPD patients have similar numbers of neutrophils.

Microsatellite DNA instability and loss of heterozygosity in bronchial asthma

Genetic alterations, such as loss of heterozygosity (LOH) or microsatellite instability (MI), have been reported in both malignant and benign disorders. In order to identify loci of deoxyribonucleic acid (DNA) mutation in asthma, MI and LOH were studied in sputum cells. DNA was extracted from cells in the sputum and blood cells of 22 patients with moderate asthma. Cells were analysed for MI and LOH using 18 polymorphic markers on chromosome 5q, 6p, 11q, 14q. Microsatellite analysis was also performed in six healthy subjects. None of the healthy individuals exhibited any genetic alteration. Genetic alterations were found in 16 of 22 asthmatic patients (73%). In total, 12 (54.5%) patients exhibited LOH only, one (4.5%) MI only, while three showed both MI and LOH. The highest incidence of LOH and MI was found on chromosome 14q. Mean immunoglobulin E and blood eosinophil levels were significantly higher in asthmatics with three or more genetic alterations. A high incidence of genetic alterations in the deoxyribonucleic acid of the sputum cells was found in asthmatic patients. Further studies are needed to identify the role of loss of heterozygosity and microsatellite instability in the investigation of genetic susceptibility of asthma and thus, in its pathogenesis.

Induced sputum in the investigation of airway inflammation of COPD

During the last decade, the method of sputum induction (SI) has offered the opportunity to study inflammation in patients with chronic obstructive pulmonary disease (COPD). This paper reviews methodological aspects of SI and summarizes its uses in the research of inflammation in COPD, including sputum cellularity and soluble markers. SI is a relatively safe, reliable, and reproducible technique, used to investigate different aspects of airway inflammation. Although various methods of induction and processing have been proved safe and highly reproducible, a generally accepted method is needed. Sputum analysis has given evidence for increased numbers of macrophages and neutrophils in COPD patients compared to normal subjects. In some studies, increased numbers of eosinophils have been also reported. Changes in various mediators have been found in sputum supernatant of COPD patients (IL-8, LTB-4 and TNF-a). The clinical usefulness of the method in the follow-up of the disease has not been explored extensively. A number of observations in patients with different clinical characteristics could be proven useful in identifying patterns of inflammation associated with different prognosis. Finally, SI could also guide treatment; such as, sputum eosinophilia in COPD could predict response to inhaled corticosteroids.

Genomic Instability on hMSH2, hMLH1, CD48 and IRF4 Loci in Pulmonary Sarcoidosis

Pulmonary sarcoidosis shares certain features with immune disease and neoplasia, and microsatellite DNA alterations are detectable in sputum specimens of pulmonary sarcoidosis patients. The biological basis and significance of these findings remain obscure, while information regarding the genetic basis of the disease is limited. Using multiplex PCR-based microsatellite analysis, we investigated 40 markers located on 1p, 1q, 2p, 2q, 3p, 5q, 6p, 7p, 9p, 11q, 14q and 17p in 38 sputum specimens of pulmonary sarcoidosis patients. Loss of heterozygosity (LOH) was found in 13 of 38 (34.2%) patients in at least one locus. These alterations occurred in the subset of markers located in or close to DNA mismatch repair (MMR) genes, hMSH2 (2p22.3–p16.1) and hMLH1 (3p21.32–p21.1), as well as in CD48 (1q21–q23) and IRF4 (6p23–p25), genes associated with lymphocyte activation. Microsatellite instability (MIN) was observed in five cases (13.2%) in at least one locus. Our data suggest that genomic instability in pulmonary sarcoidosis could be due to MMR defects, while alterations of lymphocyte-specific agents could account for granuloma formation.

Few smokers develop COPD. Why?

COPD is a common disease and its major risk factor, cigarette smoking, has been identified. However, only a minority of smokers develop clinically relevant disease. Although, the current understanding of the pathogenesis includes an "abnormal inflammation" as a response to various noxious agents, its various pathways are not clear. Oxidative stress, inflammation, tissue damage and tissue repair (remodeling) are parts of the complex procedure leading to COPD. This is a review of the available literature concerning the "susceptible" smoker. An epidemiological model is discussed, putting emphasis on the timing of the exposure to cigarette smoke. There are evidences that respiratory adenoviral infection in early life could be also an important factor. Differences in nutrition could also play a role in protecting against the oxidative stress. Airway hyperresponsiveness failed to clarify the whole picture and is still open for debate. Genetic differences are the most likely explanations to describe the "susceptible" smoker. However, the only well-established genetic risk factor is the alpha-l-antitrypsin. Other candidate genes were reviewed, alpha-l-antichymotrypsin, blood group antigens, vitamin-D binding protein, a2-macroglobulin, immunoglobulin deficiency, extracellular superoxide dismutase, secretory leukocyte proteinase inhibitor, cathepsin G, tumor necrosis factor-a gene and others. Microsatellite DNA instability in COPD could be a useful tool to identify the locus of genetic alterations leading to COPD. Thus, in addition to exposure to exogenous factors, host factors, most likely several genes, are involved and affect various pathways of the pathogenesis of COPD.

MYCL1, FHIT, SPARC, p16(INK4) and TP53 genes associated to lung cancer in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a specific form of chronic interstitial pneumonia limited to the lung and characterized by a fibroproliferative response with only minor signs of inflammation, which almost always causes rapid fibrotic destruction of the lung. In this study, we investigated genomic instability in IPF, using microsatellite DNA analysis, aiming to detect any specific genetic alterations for this disease. We used 40 highly polymorphic microsatellite DNA markers, in multiplex PCR assays, to examine 52 sputum specimens from IPF patients versus correspondent venous blood. Loss of heterozygosity (LOH) was found in 20 (38.5%) patients in at least one locus. These alterations were found on markers previously associated with lung cancer located on 1p34.3, 3p21.32-p21.1, 5q32-q33.1, 9p21 and 17p13.1 where MYCL1, FHIT, SPARC, p16(Ink4) and TP53 genes have been mapped respectively. These data provide new insights into IPF pathogenesis and a new perspective for its correlation with lung cancer.

Induced sputum in asthma

This is a short review of the use of induced sputum in bronchial asthma. The clinical applications, the procedure of this method as well as the safety validity and reproducibility of the results are discussed in detail. It is shown that sputum induction is a practical and safe procedure and an important research tool of local inflammation of bronchial asthma.

Extended genetic alterations in a patient with pulmonary sarcoidosis, a benign disease

BACKGROUND

Genetic alterations at the microsatellite level have been detected in various human malignant tissues, but have also been found in chronically inflamed tissues. Sarcoidosis is a benign disease of unknown etiology characterized by chronic inflammation, which may be associated with an increased incidence of developing malignancy.

METHODS

We examined the microsatellite alterations in a sputum cytological specimen of a patient with sarcoidosis. The DNA electrophoretic pattern of sputum was compared with that of the peripheral blood. Thirty-two microsatellite markers located at chromosomes 2p, 3p, 8p, 9p, 9q, 17p, 17q were used to reveal genetic alterations.

RESULTS

Loss of heterozygosity (LOH) was detected in eleven markers in loci 2p, 9p, 9q and 17q. LOH was observed in all four markers spanning the chromosomal arm 17q11.2-q21, suggesting a potential chromosomal deletion.

CONCLUSION

The observation of LOH in all four markers spanning the chromosomal arm 17q11.2-q21 may suggest a potential for malignancy development in this patient, or may be linked to the aetiopathogenesis of sarcoidosis. Further microsatellite fine mapping and clinical follow up of this patient are needed to clarify this.

Short-term effects of wood smoke exposure on the respiratory system among charcoal production workers

STUDY OBJECTIVES

We aimed to investigate the short-term respiratory effects of heavy, occupational wood smoke exposure among traditional charcoal production workers.

PATIENTS AND SETTING

A total of 22 charcoal workers (mean age, 41 years; 9 current smokers, 5 ex-smokers, and 8 nonsmokers) were studied and compared with a control group of 35 farmers residing in Perama, Rethymnon, Crete.

RESULTS

The charcoal workers were exposed to wood smoke for an average of 14 h/d during a mean of 23.7 days required for the burning of kilns. The workers under study were found to have significantly more cough (odds ratio [OR], 4.8; 95% confidence interval [CI], 1.2 to 19.7), sputum production (OR, 6; 95% CI, 1.4 to 26.5), wheezing (OR, 7.7; 95% CI, 1.4 to 41.5), dyspnea (OR, 28.7; 95% CI, 5.4 to 153), and hemoptysis (OR, 2.7; 95% CI, 0.7 to 55) than the control group. The prevalence of respiratory symptoms such as cough, sputum production, wheezing, and dyspnea in the charcoal workers was significantly elevated during the exposure period (OR, 5.4; 95% CI, 1.1 to 17.7; OR, 5.7; 95% CI, 1 to 31; OR, 9.8; 95% CI, 1 to 88; and OR, 36.7; 95% CI, 1 to 327, respectively). The mean +/- SD percent of predicted values of FVC, FEV(1), FEV(1)/FVC ratio, and forced expiratory flow at 25 to 75% of FVC during the exposure period were significantly lower than those before exposure: 106 +/- 10.8 vs 101 +/- 11.9, p < 0.01; 104 +/- 16 vs 97 +/- 15, p < 0.001; 81 +/- 9 vs 78 +/- 8, p < 0.001; and 95 +/- 27 vs 80 +/- 25, p < 0.01, respectively. The mean +/- SD value of peak expiratory flow at midday and in the evening during the exposure were significantly lower than before: 524 +/- 131 L/min vs 548 +/- 108 L/min, p = 0.03; and 521 +/- 135 L/min vs 547 +/- 131 L/min, p = 0.02, respectively.

CONCLUSIONS

Our results suggest that wood smoke exposure in charcoal workers is associated with increased respiratory symptoms and decreased pulmonary function. Longitudinal studies are needed to determine potential long-term adverse respiratory effects.

Diaphragmatic angiogenic growth factor mRNA responses to increased ventilation caused by hypoxia and hypercapnia

This study investigates the effect of increased ventilation on the expression of messenger ribonucleic acid (mRNA) levels of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and transforming growth factor-beta1 (TGF-beta1) in the diaphragm of intact, awake, spontaneously breathing rats, compared with responses in paralysed, mechanically-ventilated animals at similar blood gas and ventilatory levels. Four groups of intact, rats were studied in a body box, each group breathing one of four gases: room air, 12% oxygen (O2), 5% carbon dioxide (CO2), or 12% O2+5% CO2 for 1 h. Another 4 groups of paralysed, mechanically-ventilated animals were matched for arterial blood gas and ventilatory level. The results showed that VEGF mRNA abundance was increased three-fold and that of bFGF 1.5-fold when 12% O2+5% CO2 were breathed, but TGF-beta1 did not change. A significant linear relationship of VEGF and bFGF mRNA to minute ventilation was observed in awake animals (r=0.98, p<0.02 and r=0.87, p<0.03, respectively). The paralysed, mechanically-ventilated animals showed no mRNA increases for any probe. Systemic hypoxia had no additional effect on VEGF or bFGF levels in the diaphragm. It was concluded that messenger ribonucleic acid for vascular endothelial growth factor and basic fibroblast growth factor in the diaphragm rises significantly as a result of active ventilation and not due to blood gas/pH changes or to passive muscle shortening per se.

Interleukin-6 and its relationships to acute phase proteins in serous effusion differentiation

The aim of the study was to assess the discriminative power of cytokine interleukin 6 (IL-6) between transudative and exudative pleural and peritoneal effusions, and to compare IL-6 with common acute phase proteins in serous effusion differentiation. One hundred and forty-five consecutive patients with pleural or peritoneal effusion underwent diagnostic parecentesis. Patients were categorized in three groups. Malignant effusion (group A) 56 patients, non-malignant effusion (group B) 46 patients and transudate (group C) 43 patients. Serum and effusion levels of IL-6, C-reactive protein (CRP), alpha2-macroglobuline (alpha2-MG), alpha1-antitrypsin (alpha1-AT) and alpha1-acid glycoprotein (alpha1-AG) were determined. Serum IL-6 levels were significantly higher in groups A and B in comparison to group C (p<0.001 and 0.001, respectively). In addition, serum IL-6 levels were higher in group A compared to group B (p<0.001), while the studied acute phase proteins were not significantly different. All the studied parameters were higher in the effusions of groups A and B compared to group C. At a cut-off value of 72.1 fmol/ml IL-6 had a sensitivity of 82.6-89.3%, specificity of 88.4-90.7% and positive predictive value of 90.7-94.6% among the three groups. Our results suggest that IL-6 at levels > or =72.1 fmol/ml, alpha1-AT at > or =170 mg/dl and alpha1-AG at > or =52.3 mg/ml give strong evidences for malignancy in exudates.

Sucralfate alleviating post-laser-assisted uvulopalatoplasty pain

Laser-assisted uvulopalatoplasty (LAUP) is an outpatient mode of treatment for snoring and perhaps for some mild cases of obstructive sleep apnea syndrome. LAUP results in severe throat pain that usually lasts for 8 to 14 days. Sucralfate adheres to proteins at the duodenal ulcer site, forming a protective coating against gastric acid, pepsin, and bile salts, that promotes healing. If a similar protective coating could be created at the area of LAUP trauma, morbidity may be diminished. Twenty-eight patients have undergone LAUP treatment-2 with mild obstructive sleep apnea syndrome and 26 with simple snoring. A block-randomized, single blind clinical study was performed. Sucralfate was administered in 14 patients (group A) every 6 hours for 15 days as a swish and swallow, whereas the other 14 patients (group B) received water for injection with a strawberry flavor as placebo with the same dosing. As a conclusion, sucralfate significantly lowered postoperative pain and the need for analgesic drug use as well as the total number of the days the patients needed to almost reach their normal diet quantity (> or = 80% of normal quantity).

Frequent genetic alterations at the microsatellite level in cytologic sputum samples of patients with idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a disease of unknown etiology associated with DNA damage and malignancy. Bronchogenic carcinoma is the cause of death in 10% to 13% of IPF patients. Microsatellite instability (MSI) and loss of heterozygosity (LOH) are frequently detected in cancers. If these genetic alterations could be observed in IPF, they might explain the higher relative risk of lung cancer in this disease. We investigated the incidence of MSI and LOH in sputum cytologic specimens from 26 IPF patients and 26 healthy, matched subjects, using 10 highly polymorphic microsatellite markers. The electrophoretic pattern of each specimen was compared with that of corresponding peripheral blood. Thirteen (50%) patients showed genetic alterations, consisting either of MSI or LOH. Five (19%) patients exhibited MSI and 10 (39%) exhibited LOH in at least one microsatellite marker. Three (12%) patients showed LOH in more than one marker. None of the healthy subjects exhibited genetic alterations in the studied markers. No correlation was found between the detected genetic alterations and age, disease duration, blood gases, or spirometric parameters of the patients. Our findings suggest that the genetic alterations that we studied are frequent in IPF, are apparently unrelated to the severity of the disease, and may be related to tumorigenesis.

Miliary sarcoidosis following miliary tuberculosis

A patient who presented with a miliary radiographic pattern due to tuberculosis and later with a similar miliary pattern due to sarcoidosis is described. The patient, a 47-year-old man, was admitted to the hospital due to coughing, weakness, weight loss and an abnormal chest radiograph with a miliary pattern. A gastric fluid culture was positive for Mycobacterium tuberculosis and he was treated appropriately. He showed complete clinical and radiological remission. One year later he presented with a dry cough and a similar miliary pattern on the chest roentgenogram. Lung biopsy taken by thoracoscopy revealed sarcoidosis. The patient had a complete remission with corticosteroids. To our knowledge, this is the first report describing a miliary pattern as presenting radiological sign in a patient with tuberculosis who subsequently developed a new miliary pattern due to sarcoidosis.

Effect of digoxin on global respiratory muscle strength after cholecystectomy: a double blind study

BACKGROUND

Upper abdominal surgery has been shown to impair the function of the respiratory muscles. In addition, controversial results have been reported concerning the effect of digoxin on the diaphragm. The aim of this study was to investigate further the mechanism(s) of respiratory muscle dysfunction after cholecystectomy and the effect of digoxin on the impaired respiratory muscle function.

METHODS

Twenty three patients (four men) were studied before and 48 hours after surgery. Eleven received digoxin and 12 placebo. Respiratory muscle strength was assessed 48 hours after surgery by measuring mouth pressure during maximum static inspiratory (PImax) and expiratory (PEmax) efforts before and after 90 minutes of intravenous administration of 0.25 mg digoxin in a double blind, placebo controlled fashion. In addition, spirometric and pain measurements were performed.

RESULTS

Postoperatively (+48 h) PImax and PEmax decreased significantly (p<0.01) from their preoperative values in both groups by a similar degree. After administration of digoxin or placebo only the digoxin group showed a significant increase in both PImax (p<0.02) and PEmax (p<0.05) with a mean increase of 15% for PImax and 12.3% for PEmax. The mean difference in PImax (DeltaPImax) and PEmax (DeltaPEmax) between the digoxin and placebo groups was 1.01 (95% CI 0.28 to 2.2) and 1.05 (95% CI 0.04 to 2.4), respectively. Estimates of postoperative pain did not differ between the two groups. Spirometric indices showed a similar restrictive defect postoperatively in both groups but did not change after digoxin or placebo.

CONCLUSION

Digoxin improves the impaired global strength of the inspiratory and expiratory muscles after cholecystectomy and this may be clinically relevant. Muscle contractility could play a part in this impairment.

Effects of surgery on the function of the respiratory muscles

The function of the respiratory muscles (RM) is affected positively or negatively by a variety of surgical procedures. Cardiac, thoracic and upper abdominal surgery impair the RM function and lead to postoperative complications such as hypoxia, atelectasis, aspiration and infections. Preoperative assessment of RM function is cardinal to avoid or attenuate these complications. Three types of surgical procedures, lung transplantation, lung volume reduction surgery and surgery for obesity have been shown to improve RM function. A mechanism by which these types of operation have shown beneficial effects on RM function is multifactorial, depending on geometrical factors, from the reduction of hyperinflation and those depending on changes on the control of breathing. Physicians dealing with postoperative care of patients should be aware of the pathophysiological mechanisms that impair or improve respiratory muscle function as a result of a surgery as well as of the therapeutic modalities.

Microsatellite DNA instability and loss of heterozygosity in pulmonary sarcoidosis

In the present study we investigated the incidence of microsatellite instability (MI) and loss of heterozygosity (LOH) in sarcoidosis, a multisystem disease of unknown origin. We examined sputum cytological specimens from 30 patients with sarcoidosis and 30 healthy, matched subjects, using 10 highly polymorphic microsatellite markers located at several chromosomal arms. The electrophoretic pattern of each specimen was compared with the corresponding pattern of peripheral blood and any difference in the mobility of the microsatellite alleles was interpreted as MI-positive. LOH was scored as decrease in intensity of one allele relative to the other as determined from comparison of sputum and normal (blood) DNA. We found that 14 (47%) sarcoidosis patients showed genetic alterations, either MI or LOH. Six (20%) patients exhibited MI and nine (30%) exhibited LOH in at least one microsatellite marker. One of the patients exhibited MI in two microsatellite markers and three (10%) showed LOH in more than one marker. One patient showed complete deletion of the chromosomal arm 17q11.2-q21. None of the healthy subjects exhibited any genetic alteration in the studied markers. No correlation was found between the genetic alterations detected and age, disease duration, blood gases, or spirometric parameters of the patients. Our findings suggest that MI is a detectable phenomenon in sarcoidosis and seems not to be related with the severity of the disease. The detection of LOH indicates the presence of putative tumor suppressor genes at loci examined, which may play an important role in the etiopathogenesis of sarcoidosis.

Pneumoconiosis among Cretan dental technicians

Pneumoconiosis among dental technicians has recently emerged as an area of research in interstitial lung disease. This study was carried out to estimate the prevalence of pneumoconiosis in Greek dental technicians on the island of Crete. Fifty-one of the 58 dental technicians of the Heraklion Dental Technicians' Association completed an exposure history questionnaire and underwent a clinical examination, including chest radiographs, and spirometric assessment of lung volume and diffusing capacity. Values were compared with 51 control subjects. Five dental technicians showed radiological evidence of pneumoconiosis. Mean lung function values of the dental technicians, even in those with pneumoconiosis, were not significantly different from controls. No significant changes in lung function parameters were associated with smoking, exposure to metals and other contaminants. Dental technicians, however, reported more respiratory symptoms than controls (p = 0.008). Symptoms were associated to the absence of a ventilation system. We concluded that occupational exposure in dental technicians in Crete did not affect lung function. The prevalence of pneumoconiosis in this study was 9. 8%.

Microsatellite DNA instability in COPD

STUDY OBJECTIVES

Cigarette smoking is the prime cause of COPD; however, only a few smokers develop the disease. In a previous study, we demonstrated that microsatellite DNA instability (MSI) is a detectable phenomenon in sputum cells of COPD patients. Therefore, we hypothesize that this genetic alteration may indicate susceptibility to COPD.

DESIGN

In order to investigate this hypothesis, we compared smokers who developed COPD with smokers who did not develop COPD (referred to as non-COPD smokers).

SETTING

Seven highly polymorphic microsatellite markers were targeted on the DNA of sputum cells and of WBCs.

PATIENTS AND PARTICIPANTS

We studied 60 non-COPD smokers and 59 severe COPD patients with a similar smoking history (mean +/- SD) of 48+/-25 and 54+/-33 pack-years, respectively (p = 0.77). Non-COPD smokers were tested once; COPD smokers were tested twice, with an interval of 24 months between tests.

RESULTS

MSI was detected in 14 COPD patients (24%) but in none of the non-COPD smokers. In 10 COPD patients, MSI was exhibited by one microsatellite marker; in the remaining 4 COPD patients, MSI was exhibited by two different alleles. The most commonly affected marker was THRA1 on chromosome 17 (43%). No significant differences were found between MSI-positive and MSI-negative COPD patients for clinical or laboratory parameters, survival, and development of lung cancer. No change in the microsatellite alleles was found between the tests performed with a 24-month interval.

CONCLUSIONS

This study demonstrated that MSI was found exclusively in the sputum cells of smokers with COPD. The results support the hypothesis that MSI could be part of the complex genetic basis of COPD, and it could be a marker of the genetic alteration caused by smoking that allows COPD to develop.