Association between the severity of newly diagnosed obstructive sleep apnea and subclinical carotid atherosclerosis in patients without overt cardiovascular disease

OBJECTIVE

Obstructive Sleep Apnea (OSA) has been associated with both subclinical and accelerated atherosclerosis; however, it still remains unknown whether this association is unique or is mediated by the higher burden of co-existing cardio-metabolic disorders frequently seen in patients with OSA.

PATIENTS AND METHODS

A total of 40 subjects without clinically diagnosed cardiovascular disease (CVD) referred for polysomnography test were included in the study. Subjects with apnea/hypopnea index (AHI > 15/h) were classified as moderate/severe OSA. Subclinical changes in carotid atherosclerosis were assessed using mean carotid intima-media thickness (cIMT) and presence of atheromatic plaques on both carotid arteries. The measurement was performed using B-mode ultrasonogram. Framingham risk score was used in the approximation of cardiovascular risk.

RESULTS

The mean age of our cohort was 56.8 years, 70% (n = 28) of whom were males. Moderate/severe OSA was diagnosed in 21 subjects. Both groups were well matched in terms of clinical and demographic characteristics, and cardiovascular risk profile, as shown in their respective Framingham risk scores (10.4 ± 6.6 vs. 11.8 ± 8.8, p = NS). Patients with moderate/severe OSA had a higher mean AHI, 3% oxygen desaturation index, and lower minimum nocturnal oxygen saturation than controls. No significant differences were detected in terms of C-reactive protein levels. The two groups had similar cIMT (0.66 ± 0.17 vs. 0.75 ± 0.20 p = 0.33) and presence of atheromatic plaque (50% vs. 45%, p = 1.00).

CONCLUSIONS

Our study suggests that among patients with similar cardiovascular risk profile and free of overt CVD, the severity of newly diagnosed OSA was not correlated with increased inflammation or subclinical carotid atherosclerosis.

The impact of obstructive sleep apnea syndrome on renin and aldosterone

OBJECTIVE

Obstructive Sleep Apnoea Syndrome (OSAS) is a respiratory disorder characterized by recurrent airflow obstruction caused by total or partial collapse of the upper airway. OSAS is an established independent factor of cardiovascular risk together with other risk factors such as smoking and increased lipids. The aim of our study was to measure serum levels of aldosterone and renin in OSAS patients that did not suffer from arterial hypertension and compare them to matched healthy subjects in order to reveal the impact of chronic intermittent hypoxia on the renin-angiotensin-aldosterone system.

PATIENTS AND METHODS

The patients that enrolled in this study were 19 OSAS patients who had undergone overnight polysomnography and had an Apnoea Hypopnoea Index (AHI) greater than 10 events/hour. They were compared to 20 healthy non-OSAS closely matched controls. Serum aldosterone and direct renin concentration were measured by radioimmunoassay.

RESULTS

Aldosterone concentration follows a diurnal variation; therefore, all blood samples were obtained at the same time (6 AM). There were no significant differences in serum aldosterone levels between the two studied groups of OSAS patients and the healthy subjects group (140.6 pg/ml ± 25.2 vs. 133.2 pg/ml ± 18.5 with p = 0.223). Similar were the results for the renin levels (25.0 ± 6.9 vs. 24.9 ± 4.4 with p = 0.360).

CONCLUSIONS

Our study suggests that patients with OSAS, but without existing hypertension have aldosterone and renin levels similar to healthy subjects. According to our findings a direct connection between OSAS and the development of arterial hypertension may not be established via sympathetic system activation.

Pleural mesothelioma in a young male patient

We present the case of a 33-year-old male patient suffering from lymphocytic pleural effusion, as a result of pleural mesothelioma. Mesothelioma is a malignant tumor of the pleura that is mainly caused by chronic exposure to asbestos fibers and more than 40 years of exposure are needed to develop the disease. Early studies on the relationship of asbestos and mesothelioma were issued in the 1960s. Fibers migrate from the parenchyma of the lung to the visceral pleura. It is widely known that asbestos is an oncogenic factor which can cause damage to DNA. A chest x-ray may reveal pleural effusion with or without pleural thickening, whereas a chest CT may also reveal pleural thickening, uniform and/or lobular. Specific tests, such as immunohistochemical staining, are used in order to help differential diagnosis. Extrapleural pneumonectomy is used as a therapeutic option which involves removal of the lung as well as both the visceral and parietal pleura, the affected part of the pericardium and diaphragm. Surgery should be followed up by radiotherapy and chemotherapy. The surgery may lead to a mean survival rate of approximately 9-21 months. The case presented underlines that in the event of pleural effusion with a lymphocyte type physicians should consider the possibility of a pleural mesothelioma during differential diagnosis, even in relatively young patients.

The impact of obstructive sleep apnea syndrome severity on physical performance and mental health. The use of SF-36 questionnaire in sleep apnea

OBJECTIVES

Obstructive sleep apnea syndrome (OSAS) is a common disorder defined by repeated episodes of airflow cessation (apneas)leading to arterial hypoxemia and sleep disruption. OSAS has been associated with increased morbidity, mortality and diminished quality of life so far. This cross-sectional study aimed to assess the impact of OSAS on patients' Quality of Life, as measured by the Medical Outcomes Study Short Form-36 (SF-36).

PATIENTS AND METHODS

Two hundred and forty five subjects referred to the sleep laboratory and underwent full polysomnography overnight. Prior to sleep study onset, we registered height and weight, medical history, smoking habit, drug consumption. Afterwards, each patient completed the SF-36. Eighty subjects not diagnosed with sleep apnea [apnea hypopnea index (AHI < 5)] were excluded. Therefore, 165 subjects (121 male and 44 female) remained.

RESULTS AND CONCLUSIONS

Statistical analysis revealed that in patients with respiratory disturbance index (RDI) ≥ 15, (n = 115), RDI was independently associated with lower performance in role limitations due to physical problems (p = 0.005). Additionally, RDI was the only factor associated with decreased vitality (p = 0.014) and mental health scores (p = 0.047). In the same patient subgroup, body mass index (BMI) and age were associated with poorer scores in physical functioning (p < 0.001 and p = 0.003, respectively). BMI was an independent clinical predictor of worse scores in bodily pain (p = 0.006) general health (p = 0.006), social functioning (p = 0.025) and role limitations due to emotional problems (p = 0.004).

An unexpected pulmonary arterial aneurysm in a COPD patient

We present a case of an idiopathic pulmonary artery aneurysm in an asymptomatic patient who was treated for an irrelevant medical condition. Pulmonary artery aneurysms (PAA) are quite rare and can either be congenital or acquired. Congenital aneurysms are usually associated with cardiac malformations leading to pulmonary hypertension. Acquired aneurysms can be idiopathic or associated with infections (tuberculosis, syphilis), trauma, pulmonary valvular stenosis, or collagen diseases. Pulmonary artery aneurysms are not common and an idiopathic pulmonary artery aneurysm is a rare finding that could be diagnosed incidentally.

Association of ET-1 gene polymorphisms with COPD phenotypes in a Caucasian population

BACKGROUND AND AIM

The phenotypic expression of COPD consists of pulmonary emphysema and chronic bronchitis. An imprecise phenotypic definition may result in inconsistencies among genetic studies regarding COPD pathogenesis. Endothelin-1 gene polymorphisms have been linked to increased susceptibility of COPD development. The present study examined the involvement of +138 insA/delA and G198T ET-1 polymorphisms with emphysematous and bronchitic COPD phenotypes.

METHODS

In order to narrow down the phenotypic choices to either COPD-associated pulmonary emphysema or chronic bronchitis, a DLCO < 60% predicted threshold was chosen as an indicator of severe emphysema. 116 COPD smokers and 74 non-related, non-COPD smokers were evaluated.

RESULTS

Statistical analysis showed that the 4A allele of the +138insA/delA SNP and the 4A:T haplotype were associated predominantly with a chronic bronchitis phenotype, whereas the TT genotype of the G198T SNP was found to be protective from emphysema development.

CONCLUSIONS

The presence of both the 4A and T allele seems to modify the final expression of COPD towards a chronic bronchitis phenotype, since the G:3A haplotype was associated with a predominantly emphysematous phenotype in our study.

Sex hormone alterations and systemic inflammation in a group of male COPD smokers and their correlation with the +138 insA/delA endothelin-1 gene polymorphism. A case-control study

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by the presence of a low-grade systemic inflammation that is implicated in the pathogenesis of numerous extrapulmonary manifestations, such as hypogonadism. Endothelin-1 (ET-1) is a molecule that demonstrates pro-inflammatory properties and can augment the airway and systemic inflammation. Single nucleotide polymorphisms (SNPs) of the ET-1 gene that increase ET-1 serum levels are an important area of investigation. We examined the alterations in inflammatory markers [C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR)] and in the levels of testosterone, free testosterone, follicle stimulating hormone (FSH) and luteinizing hormone (LH) in a group of male COPD smokers when compared to their age-matched controls and how these alterations relate to the presence of a functional ET-1 SNP, the adenine insertion SNP +138 insA/delA.

MATERIALS AND METHODS

In this case control study, 80 male control smokers and 82 male COPD smokers were recruited for comparison. Among the male COPD smokers, 37 were carriers of the +138 insA/delA SNP. Two COPD subgroups according to genotype were formed: (1) A group of 45 males homozygous for the wild type allele (3A/3A) and (2) a group of 37 males heterozygous for the mutant allele (3A/4A).

RESULTS

Levels of testosterone and free testosterone were lower in the COPD group and even lower in the 3A/4A COPD group. CRP and ESR levels were higher in both COPD groups, but their elevation was statistically significant only for the 3A/4A COPD group. Testosterone and free testosterone levels correlated positively with PaO2 for both COPD groups. An inverse correlation between testosterone and CRP was demonstrated for the 3A/4A COPD subgroup.

CONCLUSIONS

Levels of testosterone correlated to FEV1, hypoxemia and weakly to CRP. The synchronous presence of the +138 insA/delA SNP resulted in even greater sex hormone level decline probably due to the presence of a more intense systemic inflammation.

An unexpected pulmonary infection in a patient with gastric tube interposition, reconstruction of the hypopharynx and gastric-hypopharyngeal anastomosis

Pulmonary infection by Nocardia spp. has been recognized the last decades. Nocardia is an opportunistic pathogen in immunocompromised individuals; nevertheless, it has been recognized as an uncommon pathogen in immunocompetent patients. We report a case of pulmonary infection by Nocardia asteroides in an immunocompetent host who had a history of sulfate acid aspiration, followed by gastric tube interposition, reconstruction of the hypopharynx and gastric-hypopharyngial anastomosis.

Patients with gastroesophageal reflux disease and respiratory manifestations do not present lung function disorders during cardiopulmonary exercise test

Gastroesophageal reflux disease (GERD) has been associated with a variety of pulmonary manifestations, but it is unclear if gastroesophageal reflux causes any abnormality in pulmonary function. Cardiopulmonary exercise test (CPET) is a specialized method that is used to evaluate respiratory function during exercise. The aim of this study was to reveal any abnormality of pulmonary function in patients with GERD and respiratory symptoms. We evaluated 34 patients with GERD (24 men and 10 women, aged 21-63) and extraesophageal respiratory symptoms (wheezing and/or cough) before therapy and after a 12-week treatment with double dose of omeprazole. No patient presented abnormal spirometry. CPET was performed in all the patients at baseline and after completion of the 12-week treatment. CPET parameters including VO(2) rest, VO(2) max, VCO(2) rest, VCO(2) max, O(2)-puls rest, O(2)-puls max, HR (heart rate) rest, HRmax, PETCO(2) rest, PETCO(2) max, and VE/VCO(2) slope were recorded pretreatment and posttreatment. Twenty-four patients (70.6%) had esophagitis (grade A-D), 16 patients had hiatal hernia (47.1%), and 13 patients (38.2%) tested positive for Helicobacter pylori. All of the patients completed the CPET. No one presented shortness of breath or respiratory symptoms. CPET parameters were within normal limits in all of the patients. Twenty-eight patients were reevaluated. No improvement in any CPET parameter posttreatment was observed despite remission of esophageal and extraesophageal respiratory symptoms in all patients. No statistically significant difference was observed pretreatment and posttreatment between the patients older and younger than 40 years, smokers and nonsmokers, Hp(+) and Hp(-) patients, and those with and without hiatal hernia and esophagitis. The patients with GERD and respiratory manifestations and normal spirometry present no pulmonary dysfunction during CPET. No alterations in CPET values posttreatment or differences in CPET values according to age, smoking, Hp status, presence of esophagitis, or hiatal hernia were observed.

Endothelin-1 polymorphisms involved in impaired exercise tolerance in COPD patients. A pilot study

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide that may lead to impaired exercise tolerance. In this study we exhibit the relationship between two endothelin-1 (+134 3A/4A and G198T) SNPs involved in COPD and their association to impaired exercise tolerance.

MATERIALS AND METHODS

The study population consisted of 22 COPD smokers and 32 smoking controls which underwent pulmonary function tests to assess forced expiratory volume for 1 second (FEV1), forced vital capacity (FVC), as well as cardiopulmonary exercise testing. Single nucleotide polymorphism were isolated using Real-Time PCR.

RESULTS

The distribution of both genotypes (3A3A, 3A4A, 4A4A for the +134 3A/4A and GG, GT, TT for the G198T) did not different among patients and non-COPD smoking controls. Multivariate analysis showed that the 3A4A and GG genotypes in the COPD group were independently associated with better V'O2max values (Odd's Ratio (OR) = 12.5, 95% CI = -0.85-25.1, p = 0.049, and OR = 6.1, 95% CI = 0.83-11.4, p = 0.026, respectively). On the contrary analogous analysis in the non-COPD control group, showed that the 3A3A genotype was independently associated with increased V'O2/pulse (OR = 51.5, 95% CI = 17.2-85.7, p = 0.005) and the 3A4A genotype with increased DVE/DVCO2 value (OR = 3.8, 95% CI = -0.27-7.9, p = 0.054).

DISCUSSION

Our results show that endothelin-1 gene is implicated in exercise performance in COPD patients and might play a role in adaptation of the cardiopulmonary system to exercise.

Decline in FEV1 related to genetic polymorphisms (+138insA/delA and Lys198Asn) of the endothelin-1 gene in COPD. A pilot study

BACKGROUND

Endothelin-1 (ET-1) is a potent vasoconstrictor and bronchoconstrictor but it has been shown to have also proinflammatory properties. Its ability to attract inflammatory cells in its site of production, upregulates the synthesis of adhesion molecules and stimulates the release of cytokines. The fact that cytokines have the ability to induce its synthesis and release, creates a dynamic loop for self-preservation and augmentation of the airway inflammation in Chronic Obstructive Pulmonary Disease (COPD), even after the ceasing of the noxious stimulus, i.e., cigarette smoke. Therefore, functional polymorphisms that may lead to increased levels of ET-1 may also cause an increased susceptibility to COPD development.

MATERIALS AND METHODS

We analyzed the longitudinal effect on lung function of two ET-1 gene polymorphisms in a population of 190 smokers (95 non-COPD and 95 COPD smokers). The two polymorphisms involved an insertion polymorphism (+138 adenine insertion 3A/4A, 138bp downstream from the transcription start site, exon 1) and a single nucleotide transversion polymorphism on exon 5 (G/T, Lys198Asn). A total of 190 subjects were enrolled in the study for each polymorphism and were followed for 3 years by annual spirometry sessions.

RESULTS

The adjusted annual decline of forced expiratory volume in 1 second (dFEV1) was greater for those having at least one copy of the mutated gene ins/delA compared to those with the wild type allele both in the non-COPD smokers group (mean difference in dFEV, of 19.4 ml/year, p = 0.004) and COPD smokers (mean difference in dFEV1 of 11.15 ml/year, p = 0.003). On the contrary, those heterozygous for the Lys198Asn polymorphism were found to have a slower decline in FEV1 compared to those homozygous for the wild type allele. The non-COPD smokers group had a gain-in-loss of 11,24 ml/year (p < 0.001) while the COPD-smokers group had a slower decline of 11.42 ml/year (p = 0.002). Those homozygous for the polymorphisms examined show an even greater deviation from those with the wild type allele but due to the small number comprising their group, the results don't have enough statistical power. Though, they still show the trend of the effect the polymorphisms have on annual FEV1 decline.

CONCLUSIONS

The present data shows that ET-1 and its functional polymorphisms may be implicated in COPD phenotype and severity.

Miliary pattern due to occupational lung disease in a patient with laryngeal cancer

Inhalation of metal dusts and fumes can induce a wide range of respiratory disorders, including granulomatosis, chemical pneumonitis and pulmonary interstitial disease. Laryngeal cancer is the most common cancer of the upper aerodigestive tract. We present a patient with occupational lung disease whose chest CT showed miliary nodular pattern, with concurrent laryngeal cancer who had been engaged in type printing for 22 years. Histology of the laryngeal lession showed squamous cell laryngeal cancer. Histology of the nodules showed a foreign body granulomatous response with several foreign body cells, most probably due to exposure to numerous inorganic (lanthanides, elements such us La, Ce, Nd, Sm, EU, Tb, Lu) and organic particles (such us acrylates, epoxy- and urethane-acrylates).

Determinants of specific sensitization in flour allergens in workers in bakeries with use of skin prick tests

Baker's asthma, like other forms of occupational asthma is probably the most serious manifestation of occupational allergy among bakery workers. It is caused by immunologic sensitization and subsequent allergic reactions in the airways to occupational specific airborne allergens. Skin Prick Tests (SPTs) play an important role in the diagnosis of baker's asthma and epidemiological field studies on frequencies of sensitization to flour. This paper presents a review of the available literature on prevalence of flours sensitization in bakery workers. Atopy and level of exposure appears to be a very strong determinant for sensitization to flour allergens. Prevention strategies and standard setting are discussed.

Hormonal responses to marathon running in non-elite athletes

BACKGROUND

Exercise is known to be a powerful stimulus for the endocrine system. The hormonal response to exercise is dependent on several factors including the intensity, duration, mode of exercise (endurance versus resistance), and training status of the subject. The aim of the present study was to determine the steroid hormonal response (immediately after a race and 1 week later) to endurance exercise under the real conditions of the classic Athens marathon in a group of well-trained, middle-aged, non-elite athletes.

METHODS

Blood samples were drawn 1 week before the race, directly after completion of the race, and 1 week later.

RESULTS

Serum cortisol and prolactin showed distinct rises 1 h after the race and returned to baseline 1 week later. Androstenedione and dehydroepiandrosterone sulphate did not show any changes. Total testosterone as well as free testosterone dropped significantly 1 h after the race but returned to baseline 1 week later.

CONCLUSION

In this particular group of non-elite, middle-aged marathon runners, the race resulted in an acute increase in serum cortisol and prolactin levels and in a concomitant decline in testosterone level. The aforementioned changes returned to baseline 1 week later.

Indications, results and complications of flexible fiberoptic bronchoscopy: a 5-year experience in a referral population in Greece

The aim of this study was to retrospectively review the indications, results and complications of flexible fiberoptic bronchoscopy (FFB) in an University teaching Hospital. Also, we present the radiological findings for the major causes according to computed tomography of the chest performed within 48 h of fiberoptic bronchoscopy. A total of 4,098 FFBs were performed from January 1, 2003 to December 30, 2007. For diagnostic purposes, 3769 FFBs performed (92%) and for therapeutic purposes 329 FFBs (8%) performed. Haemoptysis was the most common indication for FFB (21%), followed by fever/suspected infection (19%) and chronic cough (18%). The most common results of the diagnostic workup was nonspecific inflammation of the tracheobronchial tree (31% for haemoptysis, 38.7% for fever and 48.5% for chronic cough), with malignancy ranking second (17%, 26.1% and 26% respectively). The cytological results showed adenocarcinoma to be the most common lung cancer in both sexes (37.3% for men and 39.7% for women). The mortality rate was 0.04% and the frequency for major and minor complications was 0.56% and 0.33%, respectively. In conclusion, flexible fiberoptic bronchoscopy is a safe procedure and can play a major role in both diagnosis and treatment, as long as the requisites of preparation and supervision are followed.

Cystic thymoma coexisting with vascular dysplasia

We report the case of a 23-year-old female patient, who was admitted to our hospital because of aggravating pain in the right shoulder, right chest and ear accompanied by cough and dyspnea. Imaging revealed a soft tissue mass in the mediastinum in close relation with an additional large mass extending in the right upper thorax, right axilla and neck. The tissue obtained during surgery showed the former mass to be a cystic thymoma, being in contact with an extensive vascular dysplasia. The characteristic clinical presentation, the contribution of imaging, the results of operation, and the follow-up are rather unique. The review of the literature did not reveal similar cases.

Human genes in TB infection: their role in immune response

Tuberculosis (TB) caused by the human pathogen Mycobacterium tuberculosis, is the leading cause of morbidity and mortality caused by infectious agents worldwide. Recently, there has been an ongoing concern about the clarification of the role of specific human genes and their polymorphisms involved in TB infection. In the vast majority of individuals, innate immune pathways and T-helper 1 (Th1) cell mediated immunity are activated resulting in the lysis of the bacterium. Firstly, PTPN22 R620W polymorphism is involved in the response to cases of infection. The Arg753Gln polymorphism in TLR-2 leads to a weaker response against the M. tuberculosis. The gene of the vitamin D receptor (VDR) has a few polymorphisms (BsmI, ApaI, Taq1, FokI) whose mixed genotypes alter the immune response. Solute carrier family 11 member (SLC11A1) is a proton/divalent cation antiporter that is more familiar by its former name NRAMP1 (natural resistance associated macrophage protein 1) and can affect M. tuberculosis growth. Polymorphisms of cytokines such as IL-10, IL-6, IFN-g, TNF-a, TGF-b1 can affect the immune response in various ways. Finally, a major role is played by M. tuberculosis antigens and the Ras-associated small GTP-ase 33A. As far as we know this is the first review that collates all these polymorphisms in order to give a comprehensive image of the field, which is currently evolving.

Pulmonary complications in diabetes mellitus

Clear decrements in lung function have been reported in patients with diabetes over the past two decades, and many reports have suggested plausible pathophysiological mechanisms. However, there are no reports of functional limitations of activities of daily living ascribable to pulmonary disease in patients with diabetes. This review attempts to summarize the available information from the present literature, to describe the nature of the lung dysfunction in diabetes and the emerging clinical implications of such dysfunction.

Urinothorax: an unexpected cause of pleural effusion in a patient with non-Hodgkin lymphoma

Urinothorax is a rather rare cause of pleural effusion and its potential mechanism is urinary tract obstruction or trauma that results in urine leakage and accumulation inside the pleural space. Patients with non-Hodgkin lymphoma could present with pleural effusion due to mediastinal lymphadenopathy or extrathoracic manifestation such as urinary tract obstruction, the latter described in our case report. Physicians must be aware even of the more occult mechanisms of pleural fluid accumulations which could point to extrathoracic manifestations of involvement.

Does CPAP therapy improve erectile dysfunction in patients with obstructive sleep apnea syndrome?

OBJECTIVE

The aim of the study was to examine the quality of the characteristics of Erectile Dysfunction (ED) in men with Obstructive Sleep Apnea Syndrome (OSAS) and to investigate whether there is an improvement with the use of continuous positive airway pressure (CPAP) therapy.

MATERIALS AND METHODS

Fifteen men with OSAS and sexual dysfunction have been investigated in this follow-up study. The treatment period was for 12 weeks and the therapeutic CPAP levels were determined during the full night of the therapeutic titration.

RESULTS

In our 15 treated patients, the International Index Erectile Function (IIEF) total and all domain scores had increased after the CPAP treatment compared to the baseline, except for that of sexual desire domain.

CONCLUSIONS

CPAP therapy can improve the sexual function in ED patients with OSAS.

Sleep Apnea Syndrome in a Referral Population in Greece: Influence of Social Factors

OBJECTIVE

The aim of this work was to study whether social factors are risk factors for obstructive sleep apnea (OSA). A second objective was to investigate gender differences in relation to referral to a sleep laboratory for sleep-related breathing symptoms.

STUDY DESIGN

A retrospective cross-sectional study was conducted in the referral sleep disorders laboratory in the tertiary University Hospital in Patras in southwest Greece. A sample of 362 subjects originated from this geographic region was screened for social characteristics, i.e., marital status, occupation, and education.

RESULTS

The apnea hypopnea index (AHI) was approximately three times as high in men as in women (p < 0.05). Snoring was reported to be a symptom by 76.6% of males and 75% of females. Excessive daytime sleepiness (EDS) was reported by 25.5% of males and 15% of females. Arousals during sleep were reported by 5.7% of men and 10% of women. The ratio of subjects with concomitant disorders or symptoms did not differ between sexes (p > 0.05). The influence of age, body mass index (BMI), gender, smoking, and social characteristics on AHI was examined by multinomial logistic regression. The following factors remained independent risk factors for the presence of moderate to severe OSA (i.e., AHI > 15/h compared with AHI < 5): (1) Gender: the odds ratio (OR) of males to females was 6.23 (CI = 1.89-20.5). (2) Obesity: the OR of subjects with BMI >30.5 kg/m(2) in comparison to those with lower BMI was 3.83 (CI = 1.86-7.86). (3) Marital status: The OR of married subjects to singles was 2.30 (CI = 1.01-5.32). (4) Occupational status: The OR of subjects outside the work force was 3.85 (CI = 1.16-12.74) and that of the self-employed was 1.70 (CI = 0.70-4.10) compared to a reference group of clerks/employees.

CONCLUSION

In our study factors associated with the presence of sleep apnea include gender (men), obesity, marriage, and self-employment or being outside the work force.

Specific sensitization in wheat flour and contributing factors in traditional bakers

Skin prick tests (SPTs) play an important role in the diagnosis of bakers asthma and epidemiological field studies on frequencies of sensitization to wheat or rye flour. In many epidemiological studies the investigators have tried to reveal the determinants of specific sensitization, and atopy appears to be a very strong determinant for sensitization to flour allergens. Age and gender have not reported to be determinants of sensitization. Only one study found that sensitization in wheat flour with skin prick test was significantly associated with cigarette smoking. Few data are available on sensitization to wheat flour in populations without occupational exposure to bakery allergens. The aim of this study was to investigate the sensitization of wheat flour and other baking allergens (oat, barley, and rye flour) in traditional bakers and in cleaners in a big hospital in the same area. In addition the correlation of atopy with specific sensitization and the correlation of specific sensitization with age, sex, working hours, working years, smoking status and pack/years with use of skin prick tests.

The metabolic aspects and hormonal derangements in obstructive sleep apnoea syndrome and the role of CPAP therapy

Obstructive sleep apnea syndrome (OSAS) is part of a metabolic syndrome, whose main aspects are obesity, hypertension and diabetes, already incriminated for cardiovascular events. The evaluation of the effect of OSAS on the hormonal profile of patients shows a number of complex interactions that preclude the exact role of this syndrome among the numerous derangements on hormone levels as well as the effect of continuous positive airway pressure treatment, since many of the changes are known to occur with obesity as well. The clarification of the exact role and the mechanisms underlying these changes will help to stratify the cardiovascular and other health risks of this syndrome as well as the better application of CPAP therapy.

Obstructive sleep apnoea syndrome and genes

Obstructive sleep apnoea (OSA) is a complex disease entity strongly influenced by genetic factors, especially those that affect obesity and fat distribution, upper airway muscle tone, craniofacial morphology, ventilatory control and sleep, giving rise to the OSA phenotype. OSA can also be considered a metabolic syndrome which adversely affects multiple organ systems, especially the cardiovascular system and the brain. The most widely used clinical marker for the diagnosis of OSA is the apnoea-hypopnoea index, calculated by polysomnography. A percentage of 35 to 40% of its variance can be attributed to genetic factors. Therefore, the identification and elucidation of the genes implicated in the pathogenesis of OSA becomes a matter of extensive research and could lead to the development of therapeutic agents that can have a beneficial effect on the natural course of OSA.

Carcinoid tumour behind bronchiectasis

This report describes a female patient with bronchiectasis, presented to our department with recurrent hemoptysis. Bronchoscopy revealed nothing else but blood arising from the upper lobe bronchus. High resolution computing tomography of the lung (HRCT) revealed bronchiectasis of the upper lobe. A right upper lobectomy was performed. Behind bronchiectasis multiple nodular lesions, 5-10 mm were observed. Histological and immunohistochemical examination revealed findings consistent with peripheral typical bronchial carcinoids.

Accuracy of pulmonary function tests in predicted exercise capacity in COPD patients

PURPOSE

The purpose of this study was to examine exercise tolerance in patients with COPD from measurements of resting pulmonary function parameters.

METHODS

A total of 57 COPD patients were administered the pulmonary function test (PFT) and cardiopulmonary exercise test. The results were analyzed and essentially linear relationships emerged when each subject's VO2 peak was plotted against his individual PFT parameters. Those significant contributors were then introduced in a stepwise multiple regression analysis to determine the best predictor of the VO2 peak.

RESULTS

Stepwise multiple regressions in variables revealed that peak oxygen consumption (VO2 peak) was predicted best by the following equation: VO2 peak=(maximum voluntary ventilation x 0.024)+(forced mid-expiratory flow x 0.47)+(body surface area x 0.988)-0.913 (r=0.90; r2=0.81 SE=0.29 L/min).

CONCLUSION

We conclude that exercise capacity was predicted from measurements of resting pulmonary function parameters with excellent accuracy in the COPD patient.

Recurrent catamenial hemothorax

Endometriosis is a common cause of chronic pelvic pain and infertility affecting women of reproductive age, but the disease in rare conditions may be extragenital so may be present with a variety of symptoms. This is a report of an unusual case of pelvic endometriosis that presented with a recurrent hemothorax.

Increased Levels of Albumin in Bronchial Washing Fluid of Patients with Bronchial Carcinoma. Could Albumin be Considered as a Tumor Marker?

Background

The aim of this study was to evaluate the significance of albumin in bronchial washing fluid (BWF) and its relationship to three tumor markers (CEA, CA 19–9 and NSE).

Methods

Serum and BWF samples were collected in a group of 60 patients. Albumin and tumor markers in the BWF and serum of three groups: a control group (CG), a chronic bronchitis group (CBG) and a lung cancer group (CaG), were analyzed in a prospective cross-sectional study. The diagnostic yields of the tests in each environment (serum and BWF) were evaluated by using as cutoff points the values of the corresponding 90th percentile of CG and CBG taken together.

Results

A significant difference in albumin level (p<0.001) was noted in the BWF of patients with cancer compared with the other two groups. In addition, a significant difference in CEA level (p<0.001) was observed in the serum of cancer patients compared with the other two groups. The cutoff values for CEA in serum and albumin in BWF were 2.20 ng/mL and 2.00 g/dL, respectively. The areas under the corresponding ROC curves were 93% and 97%. Combination of CEA-serum and albumin-BWF by logistic regression analysis increased their diagnostic value.

Conclusion

Measurement of albumin levels in BWF could be a useful additional diagnostic tool to differentiate malignant from non-malignant lung diseases. Moreover, the combined measurement of CEA in serum and albumin in BWF could be of aid in the follow-up of lung cancer patients.

Effect of Body Position on PaO2 and PaCO2 during Pregnancy

BACKGROUND

The body position may have an effect on gas exchange though the magnitude of this effect has not been studied thoroughly during the three trimesters of pregnancy.

OBJECTIVES

This study analyzes the effect of body position change on arterial oxygen tension (PaO2) and arterial carbon dioxide tension (PaCO2) in healthy pregnant women.

METHODS

We examined 21 lung healthy pregnant women at the end of the first, second and third trimester of pregnancy. Blood was drawn from the radial artery first in the sitting and subsequently in the supine position. Peak expiratory flow rate was determined as well.

RESULTS

No statistically significant difference was detected between the mean values of PaO2 in the supine and in the sitting position at the end of the first trimester. On the contrary, at the end of the second trimester the mean value of PaO2 in the supine position was 92.39 +/- 1.95 mm Hg, while in the sitting position the mean PaO2 was 96.56 +/- 1.83 mm Hg (p < 0.001). At the end of the third trimester the mean PaO2 in the supine position was 90.48 +/- 2.91 mm Hg while in the sitting position the mean PaO2 was 97.48 +/- 1.46 mm Hg (p < 0.001).

CONCLUSIONS

According to our data we conclude that the statistically significant difference in PaO2 in the sitting and supine positions clearly shows that the position needs to be considered both when attempting to establish reference values and when evaluating gas tensions at the end of pregnancy.

An unusual presentation of tuberculosis

We describe a case of a male with no symptoms and normal chest X ray, diagnosed with TB. The chest computed tomography revealed a cavity formation on the upper left lobe.

Evaluation of arterial endothelin-1 levels, before and during a sleep study, in patients with bronchial asthma and chronic obstructive pulmonary disease

BACKGROUND

Endothelin (ET)-1 has been implicated in the pathogenesis of asthma and chronic obstructive pulmonary disease (COPD). The ET-1 levels are elevated during exacerbations of asthma and COPD in bronchoalveolar lavage, serum, and sputum, falling with treatment of the exacerbations.

OBJECTIVE

The aim of this study was to examine the ET-1 blood levels in stable asthmatic patients and stable COPD patients during alertness and sleep.

MATERIALS AND METHODS

We examined 48 COPD and 20 asthmatic patients. All underwent forced spirometry, measurement of SaO2 and of arterial ET-1 levels and nocturnal polysomnography. ET-1 levels were also determined during nocturnal oxyhaemoglobin desaturation.

RESULTS

The daytime SaO2 level of our asthmatic patients was higher than that of our COPD patients (p < 0.001). Daytime SaO2 level of our non-desaturator COPD patients was higher than that measured in desaturator COPD patients. Nightime SaO2 level in our asthmatic patients was higher than that in our desaturator COPD patients (p < 0.001). Daytime ET-1 levels in desaturator COPD patients were higher than those observed in normal individuals, in non-desaturator COPD patients and in asthmatic patients. The COPD desaturator patients had higher levels of ET-1 during nighttime than during daytime (p < 0.001).

CONCLUSION

Asthmatic patients did not exhibit desaturation of haemoglobin during the night. ET-1 levels are significantly higher in desaturator COPD patients compared with non-desaturator COPD patients, both during the day and during the night. ET-1 levels in stable COPD patients are significantly higher than in patients with stable asthma. These findings are consistent with the hypothesis that ET-1 is implicated in the pathogenesis of COPD and asthma.

Erectile dysfunction in men with obstructive sleep apnea syndrome: a randomized study of the efficacy of sildenafil and continuous positive airway pressure

The aim of this study was to compare the efficacy of sildenafil and continuous positive airway pressure (CPAP) in men with erectile dysfunction (ED) and obstructive sleep apnea syndrome (OSAS). In all, 30 men were randomly treated for 12 weeks either with sildenafil 100 mg before intercourse (15 men) or CPAP during night time sleep (15 men). Under sildenafil, 97/180 (53.9%) of attempted intercourses were successful compared to 33/138 (23.9%) under CPAP. The mean IIEF (erectile function domain score) was 12.9 and 9.3 after sildenafil and CPAP treatment, respectively (P=0.007), compared to 7.9 and 7 at baseline. In all, 53.3% of patients were satisfied with sildenafil and 20% with CPAP for ED treatment (P=0.058). Although sildenafil was superior to CPAP, comorbidities and OSAS per se possibly resulted in a lower effectiveness of sildenafil compared to that in the general population of ED men. While about half of the patients were not satisfied even with the more effective treatment, we conclude that a combination of the two therapeutic tools or a different therapeutic mode should be studied further.

Arterial oxygen tension during sleep in the third trimester of pregnancy

BACKGROUND

Changes during pregnancy include reduced functional residual capacity (FRC) and residual volume (RV), increased alveolar difference for oxygen and, in the supine position, reduced cardiac output. In conjunction with sleep-related disturbances, these changes could lead to maternal oxygen desaturation during sleep.

OBJECTIVES

Because of conflicting data from respiratory sleep studies in pregnancy, we performed complete polysomnography on 21 pregnant women at the 36th week of gestation and again postpartum. We also measured the partial pressure of oxygen in the arterial blood (PaO2) in the supine and sitting positions.

METHODS

We tested 21 healthy pregnant women at the 36th week of gestation. Arterial samples were taken in the sitting position. Complete polysomnography was performed in all of the pregnant women. Before the polysomnography arterial samples were taken in the supine and sitting positions and then every 2 h until termination of the study.

RESULTS

We did not find any correlation between SaO2/PaO2 levels and apnea, hypopnea or percent of rapid eye movement (REM) sleep. The frequency of apnea and hypopnea was significantly lower during pregnancy (5.81 +/- 2.1 apneas or hypopneas per hour of sleep) than postpartum (12.1 +/- 2.7 apneas or hypopneas per hour of sleep) (p < 0.001), which may be due to the raised level of progesterone. The PaO2 levels in the supine position were significantly lower than in the sitting position at 36 weeks of gestation (p < 0.001). No differences were found between PaO2 levels in the sitting and supine positions postpartum (p < 0.5).

CONCLUSIONS

According to our results we conclude that 1) the frequency of apnea and hypopnea in pregnancy was significantly lower than postpartum, and 2) a significant difference in PaO2 levels in the sitting and supine positions was observed at 36 weeks of gestation.

Drug-resistance of Mycobacterium tuberculosis in Patras, Greece

BACKGROUND

The global distribution of drug resistant tuberculosis reflects the quality of tuberculosis control worldwide and is still a major public health-problem. To our knowledge, no data exists in literature about resistance to anti-tuberculosis drugs in Greece.

METHODS

The aim of this study was to determine the prevalence of resistance to the main anti-tuberculosis drugs in newly and previously treated tuberculosis patients, in the region of Patras, in Greece and to evaluate the contribution of foreign-born and human immunodeficiency virus (HIV) positive cases to drug resistance.

RESULTS

A total of 207 initial isolates of Mycobacterium tuberculosis were analysed. All clinical specimens submitted for cultural diagnosis were collected before chemotherapy commenced. The age of the patients varied from 16 to 78 years old. Sex distribution was 144 males (69.56%) and 63 females (30.43%). Nineteen patients (9.17%) were recent immigrants in Greece. All the patients were HIV-negative. One hundred-one initial isolates of Mycobacterium tuberculosis (48.79%) were susceptible to all first-line anti-tuberculosis drugs, isoniazid, streptomycin, ethambutol and rifampicin. The prevalence of primary mono- and poly-drug resistance was lower (isoniazid 5.79%, streptomycin 4.34%, ethambutol 1.93%, isoniazid + streptomycin 3.38%, isoniazid + ethambutol 0.9%, isoniazid + streptomycin + ethambutol 1.44%) when compared with the prevalence of secondary (acquired) mono- and poly-drug resistance (isoniazid 8.69%, streptomycin 10.14%, ethambutol 3.86%, isoniazid + streptomycin 3.86%, isoniazid + rifampicin 1.44%, isoniazid + streptomycin + ethambutol 4.83%, isoniazid + streptomycin + rifampicin 1.44%). No primary mono - resistance to rifampicin, or primary multi - drug resistance (defined here as Mycobacterium tuberculosis resistant to at least isoniazid and rifampicin) were observed.

CONCLUSIONS

According to our data, overall drug resistance was high. Fortunately, multi-drug resistance tuberculosis was not common but special efforts are needed to monitor the prevalence of drug resistance and to ensure adequate treatment in all the population.

Hematologic and biochemical laboratory parameters before and after a marathon race

Marathon racing is a strenuous exercise that has a profound effect on many laboratory parameters. Participants in marathon races may require abstinence of exercise and the performance of laboratory assays several days after the event. The aim of this study was to evaluate the possible changes in blood cell count and biochemical parameters observed in participants in a marathon 3 days before and 3 days after and before and immediately after a cardiopulmonary exercise test. Incremental cycle ergometry up to maximal capacity was performed in 7 marathon runners, 3 days before and 3 days after the race. The % peak oxygen consumption (peak %VO(2)) achieved was statistically significantly lower after than before the race ( p = 0.02). No statistically significant differences were observed in cardiac frequency ( p = 0.148) or blood cell count ( p = 0.501). Also, the concentration of sodium, potassium, calcium, magnesium, lactate dehydrogenase (LDH), phosphocreatine kinase (CPK) and glucose, measured before and immediately after the pulmonary exercise test, did not differ significantly ( p < 0.5). A significant percentage of the laboratory results were outside the standard reference rates. According to our data, exercise performance, as expressed by peak %VO(2), continued to be decreased in marathon runners 3 days after the race. The blood cell count and biochemical parameters did not differ significantly but many marathon runners were outside the standard reference rates. Unfortunately, only 7 subjects were available for this study. Further studies with larger samples and with samples obtained at multiple times during and after exercise are needed to clarify the effects of long-distance running.

Can High Resolution Computed Tomography Predict Lung Function in Patients with Chronic Obstructive Pulmonary Disease?

High-resolution computed tomography (HRCT) is a useful method for quantifying the extent of emphysema. Few reports have mentioned the relationships between HRCT scans and pulmonary function tests in chronic obstructive pulmonary disease (COPD). For diagnosis, COPD requires chronic airflow limitation and emphysema and/or chronic bronchitis. We examined 20 who were previous smokers with middle to moderate COPD. All were normocapnic with mean arterial oxygen pressure (PaO2) 77,52 +/- 16,789 mmHg. Forced spirometry, somatic plethysmography and cardiopulmonary exercise test were performed in each patient. HRCT was performed in both full inspiration and full expiration at three levels through the upper (at the aortic arch), lower (2 cm above the diaphragm), and middle lung (midpoint between upper and lower) levels. During expiration all pulmonary function parameters correlated with the HRCT grade in the middle right and left part of the lungs. The middle right part of the lung during expiration correlated statistically significant with MVV (r = -0.681, p = 0.001), forced vital capacity (FVC) (r = -0.477, p = 0.027), forced expiratory volumein 1 sec (FEV1) (r = -0.632, p = 0.002), resistance (r = 0.674, p = 0.001), residual volume (RV) (r = 0.733, p = 0.001), total lung capacity (TLC) (r = 0.696, p = 0.001), functional residual capacity (FRC) (r = 0.752, p = 0.001) and peak oxygen consumption during exercise (VO2) (r = -0.493, p = 0.023). The middle left part of the lung during expiration correlated statistically significant with MVV (r = -0.673, p = 0.001), FVC (r = -0.493, p = 0.027), FEV1 (r = -0.629, p = 0.003), resistance (r = 0.593,p = 0.005), RV (r = 0.601, p = 0.005), TLC (r = 0.546, p = 0.012), FRC (r = 0.594, p = 0.006) and peak VO2 (r = -0.525, p = 0.015). Forced expiratory volume in 1 sec (FEV1), which is a well-established measure of airflow obstruction, correlated with the HRCT grade (1) in the middle left part of the lung during inspiration (r = -0.468, p = 0.035) and during expiration (r = - 0.629, p = 0.003) (2) in the lower right lung during inspiration (r = -0.567, p = 0.007) and during expiration (r = -0.558, p = 0.008) (3) in the lower left lung during inspiration (r = -0.542, p = 0.011) and during expiration (r = -0.558, p = 0.008) (4) in the upper right lung during expiration (r = -0.469, p = 0.037) (5) in the upper left lung during expiration (r = -0.463, p = 0.035) and (6) in the middle right lung during expiration (r = -0.632, p = 0.002). According to our results HRCT was a valuable tool for evaluating the severity of COPD--especially the middle right and left part of the lungs, during expiration--and correlated well with pulmonary function tests.

Normal pregnancy and oxygenation during sleep

Pregnancy is associated with significant alterations in respiratory function. Changes during pregnancy include reduced functional residual capacity (FRC) and residual volume (RV), increased alveolar-arterial difference for oxygen (A-alphaPO2) and in the supine position, reduced cardiac output. In conjunction with sleep-related apneas or hypopneas, these could lead to maternal oxygen desaturation during sleep. Because of the conflicting data from sleep studies in late pregnancy, we performed complete polysomnography on 11 pregnant women at 36 weeks of gestation and again postpartum. We also measured the PaO2, every 2h. The frequency of apneas and hypopneas was significantly lower during pregnancy compared with that on the postpartum control night. PaO2 levels in the supine position, during sleep, were also significantly lower during pregnancy compared to the postpartum period. No correlation was observed between PaO2 levels and apneas or hypopneas or percent of REM sleep.

Endothelin-1 levels in the pathophysiology of chronic obstructive pulmonary disease and bronchial asthma

BACKGROUND

Endothelin-1 (ET-1) has been implicated in the pathogenesis of asthma and chronic obstructive pulmonary disease (COPD). The ET-1 levels are elevated during exacerbations of asthma and COPD in bronchoalveolar lavage, serum, and sputum and fails with treatment of the exacerbations. Hypoxemia stimulates ET-1 secretion.

OBJECTIVE

The aim of this study was to examine the serum ET-1 levels in stable asthmatic and COPD patients.

MATERIALS AND METHODS

We examined 48 COPD and 26 asthmatic patients and 34 normal subjects. We collected arterial samples to measure baseline ET-1 levels in all patients and in the control group, during the day. All the patients underwent formal polysomnography (EEG, ECG, airflow, respiratory muscle movement, oximeter) to detect the presence of nocturnal, nonapneic, and oxyhemoglobin desaturation. Twelve of the COPD patients and six of the asthmatic patients were disqualified because of inadequate sleep or sleep apnea syndrome. Nineteen of the COPD patients desaturated below a baseline sleep saturation of 90% for 5 min or more, reaching a nadir saturation of at least 85%. We collected arterial samples to measure ET-1 levels, 5 min after the first period of desaturation in each of the 19 desaturators COPD patients. None of the 20 asthmatic patients exhibited oxyhemoglobin desaturation during sleep.

RESULTS

Baseline arterial ET-1 levels during the day were significantly higher in "desaturators" COPD patients (2.08+/-0.28 pg/ml) compared to "non-desaturators" COPD patients (1.38+/-0.16 pg/ml) (P<0.001) and to asthmatics (0.7+/-0.85 pg/ml) (P<0.001). ET-1 Levels in normal subjects were 1.221+/-0.02 pg/ml. In "desaturators" COPD patients ET-1 levels during the night, 5 min after the first oxyhemoglobin desaturation, were significantly higher (4.28+/-1.10 pg/ml) compared to those during the day (2.08+/-0.28 pg/ml) (P<0.001). A significant negative correlation was observed between ET-1 levels and degree of desaturation during the day (P=0.005, r=0.632) and during the night (P<0.001, r=0.930) in "desaturators" COPD patients.

CONCLUSION

According to our results: (1) ET-1 levels were significantly higher in "desaturators" COPD patients than in "non-desaturators" COPD and in asthmatics; (2) ET-1 levels were significantly higher during the night than during the day in "desaturators" COPD patients; (3) the degree of desaturation correlated negatively with the ET-1 levels in "desaturators" COPD patients, both during daytime and nighttime. These findings are consistent with the hypothesis that ET-1 is implicated in the pathophysiology of asthma and COPD, especially if nocturnal, nonapneic, oxyhemoglobin desaturation exists.

Arterial endothelin-1 in interstitial lung disease patients with pulmonary hypertension

The aim of this study was to evaluate the plasma arterial levels of Endothelin-1 (ET-1) and their relationship with hypoxia and pulmonary hypertension (PH) in patients with interstitial lung disease (ILD). Incremental cycle ergometry was performed in all patients up to maximal capacity. ET-1 levels during exercise (2.2 +/- 0.36 pgr/ml) were significantly higher than at rest (1.73 +/- 0.37 pgr/ml) (p < 0.001). ET-1 levels were also significantly correlated with arterial oxygen (PaO2) (r = -0.935, p < 0.001) and mean pulmonary arterial pressure (Ppa) (r = 0.657, p < 0.001). Increased pulmonary and peripheral blood levels of ET-1 have been described in, and postulated to contribute to, the pathophysiology of several lung diseases. In agreement with this, in the current study, the plasma arterial levels of ET-1 were also found to be significantly elevated in patients with various interstitial lung disorders during exercise, especially in those with severe hypoxia and pulmonary hypertension.

Mechanisms of endothelin-1 elevation in chronic obstructive pulmonary disease patients with nocturnal oxyhemoglobin desaturation

BACKGROUND

Nonapneic, oxyhemoglobin desaturation associated with sleep has been described in patients with chronic obstructive pulmonary disease (COPD). Hypoxemia stimulates endothelin-1 (ET-1) secretion. Once released, ET-1 can act locally to elicit sustained pulmonary artery vasoconstriction, bronchoconstriction and activation of alveolar macrophages.

OBJECTIVE

The aim of this study was to examine a possible correlation between ET-1 levels and nocturnal, nonapneic, oxyhemoglobin desaturation during sleep, in patients with COPD.

METHODS

We examined 48 COPD patients with formal polysomnography (EEG, ECG, airflow, respiratory muscle movement, oximeter) to detect the presence of nocturnal, nonapneic, oxyhemoglobin desaturation. Twelve of them were disqualified because of inadequate sleep or sleep apnea syndrome. Nineteen of them desaturated below a baseline sleep saturation of 90% for 5 min or more, reaching a nadir saturation of at least 85%. We collected arterial samples to measure ET-1 levels, after 5 min of the first period of desaturation, in each of the 19 patients. We also collected arterial samples in the morning, before the study, to measure baseline ET-1 levels in all patients.

RESULTS

Baseline arterial ET-1 levels during the day were very significantly higher in 'desaturator' COPD patients (2.058 +/- 0.252 pg/ml) compared to 'non-desaturator' COPD patients (1.382 +/- 0.159 pg/ml; p < 0.001). Also in 'desaturator' COPD patients ET-1, levels during the night were significantly higher (4.297 +/- 1.107 pg/ml) compared to those during the day (p < or = 0.001) and a significant negative correlation was observed between ET-1 levels and degree of desaturation (p < 0.0001, r = 0.9305).

CONCLUSIONS

According to our study we can conclude that (1) ET-1 levels are significantly higher in 'desaturator' COPD patients both during the day and during the night, and (2) ET-1 levels correlate negatively significant with the degree of the oxyhemoglobin desaturation. These findings are consistent with the hypothesis that ET-1 plays a very important role in the pathophysiological manifestations of COPD patients.

Arterial and bronchoalveolar lavage fluid endothelin-1 concentration in asthma

Endothelins are a family of peptide mediators that have a number of biological properties, including the ability to act as bronchoconstrictors and vasoconstrictors of isolated airways and vessels. Endothelin-1 (ET-1) is the more potent peptide compared with the other two peptides of the family. To examine a possible involvement of ET- 1 in the pathogenesis of asthma, we measured arterial ET-1 levels in 11 patients with atopic asthma during attack and during remission, and in 11 healthy control subjects. We also performed fiberoptic bonchoscopy and bronchoalveolar lavage (BAL) to measure ET-1 levels in the 11 asthmatic patients during remission, and in the 11 healthy control subjects. ET-1 concentrations in arterial blood and in BAL were measured by a radioimmunoassay method. Arterial ET-1 levels were very significantly higher in asthma attack (3.67 +/- 0.51 pg ml(-1)) and in asthma remission (2.65 +/- 10.62 pg ml(-1)) compared with those of the healthy controls (1.37 +/- 0.14 pg ml(-1)) (P < 0.001). Arterial ET-1 levels were also very significantly higher during asthma attack compared with those in asthma remission (P < 0.001). BAL ET-1 levels were significantly higher in asthma remission (0.73 +/- 0.53 pmol g(-1)) compared with those of the healthy controls (0.16 +/- 0.02 pmol g(-1)) (P < 0.05). No correlation was observed between arterial and BAL ET-1 levels, PaO2 and peak expiratory flow rate (PEFR). These data are consistent with the hypothesis that ET-1 contributes to the pathophysiology of asthma. However, it is likely that the true importance of this vasoconstrictor peptide will only be revealed by pharmacological studies with specific receptor antagonists.

Chronic obstructive pulmonary disease management among primary healthcare physicians

The aim of this study was to evaluate the dissemination of chronic obstructive pulmonary disease (COPD) management guidelines among primary healthcare physicians in Greece. One hundred and five of 120 (87.5% response rate) completed a questionnaire about COPD morbidity and management. One in eight patients examined by a primary care physician suffered from COPD. Forty-eight physicians treated their COPD patients according to the pulmonologist's recommendations and 69 according to COPD management guidelines. All the physicians encouraged and supported their COPD patients in stopping smoking, but continuous abstinence was low. The most commonly prescribed drugs were beta 2-agonist inhalers (14.8%), corticosteroid inhalers (13.47%), antibiotics (12.6%) and influenza vaccines (12.6%). The most commonly prescribed antibiotics were cephalosporins (33.72%), macrolides (27.71%) and amoxycillin plus clavulanic acid (25.3%). According to the present study, chronic obstructive pulmonary disease management among primary healthcare physicians was not in total accordance with current guidelines. Better dissemination of chronic obstructive pulmonary disease guidelines among specialists and primary healthcare physicians will hopefully make chronic obstructive pulmonary disease management in outpatients optimal.

A new perspective in learning pattern generation for teaching neural networks

This article deals with the Learning Patterns (LPs)' generation, a major aspect of Feed-Forward Artificial Neural Networks (FANNs)' learning process. Currently, more work is done to understand the mechanisms and improve the speed, learning accuracy, and implementation features of FANNs' teaching algorithms, though little is done towards the development of enhanced techniques that would extract experts' knowledge (from examples, rules, etc.) and obtain standardised LPs that would improve this learning process. A new approach in generating LPs is thereby introduced, that is used to train a new Medical Decision Support System (MDSS) based on FANNs, and its performance is analysed and compared with previous methods. It can handle incomplete data archives, individually boost any particular dataum special characteristics, and its application induces the FANNs to show better convergent facets. The efficiency of the resulting MDSS was thoroughly tested by pulmonologists and haematologists using medical data archives of a regional hospital.

Non-invasive estimation of pulmonary arterial hypertension in chronic obstructive pulmonary disease

The feasibility and reliability of the combination of several noninvasive methods using a multivariate method of analysis to predict pulmonary artery hypertension (PAH) is evaluated in 20 patients with chronic obstructive pulmonary disease. These methods comprised arterial blood gases (Pao2, Paco2), pulmonary functional parameters (FEV1), echo-Doppler parameters (tricuspid regurgitation jets, acceleration time on pulmonary valve), computed tomography measurements (transhilar distance, hilar thoracic index, and measurement of the descending branch of the right pulmonary artery to the lower lobe). A multiple stepwise regression analysis (including one Doppler parameter, two parameters of arterial blood gases, and one functional parameter) revealed a coefficient of determination (R2) equal to 0.954 for mean pulmonary artery pressure (MPAP) with a standard error of estimate (S.E.E.) of 5.25 mmHg. A stepwise regression analysis including computed tomography and radiographic parameters revealed an R2 equal to 0.970 for PAP with a S.E.E. of 4.26 mmHg. Logistical regression analysis classified correctly 80% of patients with PAH using noninvasive methods such as the diameter of the main pulmonary artery and the diameter of the left pulmonary arterial branch calculated by computed tomography. Not only the presence of PAH but also the level of MPAP can be estimated by the combination of multiple stepwise and logistical regression analyses.

Sequential chemo-immunotherapy treatment of metastatic malignant melanoma

Twelve patients with recurring metastatic inoperable malignant melanoma (performance status ECOG 0-1), received the following chemotherapy: tamoxifen p.o., carmustine i.v., dacarbazine i.v., and cisplatin i.v., followed by immunotherapy: interleukin-2 s.c. and interferon-alpha s.c. The treatment cycle was repeated every 6 weeks. Total response rate was 66.6%, with 25% (3 patients) achieving complete cure that has persisted for a period of 17.75 months (mean). In addition, different responses to treatment were observed between the local recurrence lesions and the metastatic lesions. Medium to severe side effects were observed, all but one of them being reversible (neurotoxicity), such as fever, anemia, leukopenia: nephrotoxicity, neurotoxicity, and dyspnea.