Panagiotis Behrakis

Short-term Pulmonary Effects of Using an Electronic Cigarette Impact on Respiratory Flow Resistance, Impedance, and Exhaled Nitric Oxide

BACKGROUND Debate exists over the scientific evidence for claims that electronic cigarettes (e-cigarettes) have no health-related ramifications. This study aimed to assess whether using an e-cigarette for 5 min has an impact on the pulmonary function tests and fraction of exhaled nitric oxide (Feno) of healthy adult smokers. METHODS Thirty healthy smokers (aged 19-56 years, 14 men) participated in this laboratory-based experimental vs control group study. Ab lib use of an e-cigarette for 5 min with the cartridge included (experimental group, n = 30) or removed from the device (control group, n = 10) was assessed. RESULTS Using an e-cigarette for 5 min led to an immediate decrease in Feno within the experimental group by 2.14 ppb (P = .005) but not in the control group (P = .859). Total respiratory impedance at 5 Hz in the experimental group was found to also increase by 0.033 kPa/(L/s) (P < .001), and flow respiratory resistance at 5 Hz, 10 Hz, and 20 Hz also statistically increased. Regression analyses controlling for baseline measurements indicated a statistically significant decrease in Feno and an increase in impedance by 0.04 kPa/(L/s) (P = .003), respiratory resistance at 5 Hz by 0.04 kPa/(L/s) (P = .003), at 10 Hz by 0.034 kPa/(L/s) (P = .008), at 20 Hz by 0.043 kPa/(L/s) (P = .007), and overall peripheral airway resistance (β, 0.042 kPa/[L/s]; P = .024), after using an e-cigarette. CONCLUSIONS e-Cigarettes assessed in the context of this study were found to have immediate adverse physiologic effects after short-term use that are similar to some of the effects seen with tobacco smoking; however, the long-term health effects of e-cigarette use are unknown but potentially adverse and worthy of further investigation.

Original ResearchTobacco Cessation and PreventionShort-term Pulmonary Effects of Using an Electronic Cigarette: Impact on Respiratory Flow Resistance, Impedance, and Exhaled Nitric Oxide

BACKGROUND Debate exists over the scientific evidence for claims that electronic cigarettes (e-cigarettes) have no health-related ramifications. This study aimed to assess whether using an e-cigarette for 5 min has an impact on the pulmonary function tests and fraction of exhaled nitric oxide (Feno) of healthy adult smokers. METHODS Thirty healthy smokers (aged 19-56 years, 14 men) participated in this laboratory-based experimental vs control group study. Ab lib use of an e-cigarette for 5 min with the cartridge included (experimental group, n = 30) or removed from the device (control group, n = 10) was assessed. RESULTS Using an e-cigarette for 5 min led to an immediate decrease in Feno within the experimental group by 2.14 ppb (P = .005) but not in the control group (P = .859). Total respiratory impedance at 5 Hz in the experimental group was found to also increase by 0.033 kPa/(L/s) (P < .001), and flow respiratory resistance at 5 Hz, 10 Hz, and 20 Hz also statistically increased. Regression analyses controlling for baseline measurements indicated a statistically significant decrease in Feno and an increase in impedance by 0.04 kPa/(L/s) (P = .003), respiratory resistance at 5 Hz by 0.04 kPa/(L/s) (P = .003), at 10 Hz by 0.034 kPa/(L/s) (P = .008), at 20 Hz by 0.043 kPa/(L/s) (P = .007), and overall peripheral airway resistance (β, 0.042 kPa/[L/s]; P = .024), after using an e-cigarette. CONCLUSIONS e-Cigarettes assessed in the context of this study were found to have immediate adverse physiologic effects after short-term use that are similar to some of the effects seen with tobacco smoking; however, the long-term health effects of e-cigarette use are unknown but potentially adverse and worthy of further investigation.

Protective effect of L-cysteine and glutathione on rat brain Na+,K+-ATPase inhibition induced by free radicals.

Abstract The aim of this study was to investigate whether the preincubation of brain homogenates with L-phenylalanine (Phe), L-cysteine (Cys) or reduced glutathione (G SH) could reverse the free radical effects on Na+,K+-ATPase activity. Two well established systems were used for the production of free radicals: 1) FeSO4 (84 μᴍ ) plus ascorbic acid (400 μᴍ ) and 2) FeSO4, ascorbic acid and H2O2 (1 mᴍ) for 10 min at 37 °C in homogenates of adult rat whole brain. Changes in brain Na+,K+-ATPase activity and total antioxidant status (TAS) were studied in the presence of each system separately, with or without Phe, Cys or GSH. TAS value reflects the amount of free radicals and the capacity of the antioxidant enzymes to limit the free radicals in the homogenate. Na+,K+-ATPase was inhibited by 35-50% and TAS value was decreased by 50-60% by both systems of free radical production. The enzymatic inhibition was completely reversed and TAS value increased by 150-180% when brain homogenates were preincubated with 0.83 mᴍ Cys or GSH. However, this Na+,K+-ATPase inhibition was not affected by 1.80 mᴍ Phe, which produced a 45-50% increase in TAS value. It is suggested that the antioxidant action of Cys and GSH may be due to the binding of free radicals to sulfhydryl groups of the molecule, so that free radicals cannot induce Na+,K+-ATPase inhibition. Moreover, Cys and GSH could regulate towards normal values the neural excitability and metabolic energy production, which may be disturbed by free radical action on Na+,K+-ATPase.

Exhaled Breath Condensate: Technical and Diagnostic Aspects

Purpose. The aim of this study was to evaluate the 30-year progress of research on exhaled breath condensate in a disease-based approach. Methods. We searched PubMed/Medline, ScienceDirect, and Google Scholar using the following keywords: exhaled breath condensate (EBC), biomarkers, pH, asthma, gastroesophageal reflux (GERD), smoking, COPD, lung cancer, NSCLC, mechanical ventilation, cystic fibrosis, pulmonary arterial hypertension (PAH), idiopathic pulmonary fibrosis, interstitial lung diseases, obstructive sleep apnea (OSA), and drugs. Results. We found 12600 related articles in total in Google Scholar, 1807 in ScienceDirect, and 1081 in PubMed/Medline, published from 1980 to October 2014. 228 original investigation and review articles were eligible. Conclusions. There is rapidly increasing number of innovative articles, covering all the areas of modern respiratory medicine and expanding EBC potential clinical applications to other fields of internal medicine. However, the majority of published papers represent the results of small-scale studies and thus current knowledge must be further evaluated in large cohorts. In regard to the potential clinical use of EBC-analysis, several limitations must be pointed out, including poor reproducibility of biomarkers and absence of large surveys towards determination of reference-normal values. In conclusion, contemporary EBC-analysis is an intriguing achievement, but still in early stage when it comes to its application in clinical practice.

The immediate effect of a Boston brace on lung volumes and pulmonary compliance in mild adolescent idiopathic scoliosis

Abstract Idiopathic scoliosis (IS) is known to result in lung volume and pulmonary compliance reduction. Boston brace treatment of IS is an additional factor causing restrictive respiratory syndrome due to external chest wall compression. Nevertheless, the immediate effect of Boston bracing on the pulmonary compliance of scoliotic patients has not been studied systematically. Spirometric and plethysmographic lung volumes, static lung compliance (CST(L)) and specific lung compliance (CST(L)/functional residual capacity) of 15 scoliotic adolescents (14 females and 1 male, of mean age 14.1 ± 1.67 years, with mean Cobb angle 24.1°± 7.88°) were recorded twice, in a random sequence: once without the Boston brace (nBB) and once immediately after wearing the brace (BB). Our findings showed that bracing reduced vital capacity, residual volume, functional residual capacity (FRC), total lung capacity, and forced expiratory volume in 1 s in a proportional and significant way (P < 0.001). CST(L) was also significantly reduced (P < 0.001), but CST(L)/FRC remained unaltered. All BB and nBB indices were highly correlated. We concluded that Boston bracing in IS patients results in an immediate, predictable, and uniform reduction of lung volumes and pulmonary compliance. The reduction of CST(L) under bracing conditions was related to the decrease of lung volume; the CST(L)/FRC remained unaltered.

Smoking cessation can improve quality of life among COPD patients: Validation of the clinical COPD questionnaire into Greek

BackgroundChronic obstructive pulmonary disease (COPD) remains a major public health problem that affects the quality of life of patients, however smoking cessation may emeliorate the functional effects of COPD and alter patient quality of life.Objective-designThe aim of this study was to validate the Clinical COPD Questionnaire (CCQ) into Greek and with such to evaluate the quality of life in patients with different stages of COPD, as also assess their quality of life before and after smoking cessation.ResultsThe internal validity of questionnaire was high (Cronbachs a = 0.92). The reliability of equivalent types in 16 stabilized patients also was high (ICC = 0.99). In general the domains within the CCQ were strongly correlated with each other, while each domain in separate was strongly correlated with the overall CCQ score (r2 = 0.953, r2 = 0.915 and r2 = 0.842 in regards to the functional, symptomatic and mental domain, respectively). The CCQ scores were also correlated with FEV1, (r2 = -0.252, p < 0.001), FEV1/FVC, (r2 = -0.135, p < 0.001) as also with the quality of life questionnaire SF-12 (r2 = -0.384, p < 0.001). Smoking cessation also lead to a significant reduction in CCQ score and increase in the SF-12 score.ConclusionsThe self administered CCQ indicates satisfactory validity, reliability and responsiveness and may be used in clinical practice to assess patient quality of life. Moreover the CCQ indicated the health related quality of life gains attributable to smoking cessation among COPD patients, projecting smoking cessation as a key target in COPD patient management.

Linear and nonlinear analysis of pressure and flow during mechanical ventilation

Objective: Linear modeling as a method of exploring respiratory mechanics during mechanical ventilation, was compared to nonlinear modeling for flow dependence of resistance in three distinct groups of patients, those with: (a) normal respiratory function (NRF), (b) chronic obstructive pulmonary disease (COPD), or (c) adult respiratory distress syndrome (ARDS). Design and patients: Airways opening pressure (Pao), flow (V′), and volume (V) signals were recorded in 32 ICU mechanically ventilated patients, under sedation and muscle relaxation (10 NRF, 11 COPD, 11 ARDS). All patients were ventilated with controlled mandatory ventilation mode at three levels of end-expiratory pressure (PEEPe): 0, 5, and 10 hPa. Data were analyzed according to: (a) Pao = PE + Ers V + Rrs V′ and (b) Pao = PE + Ers V + k1V′ + k2|V′|V′, where Ers and Rrs represent the intubated respiratory system (RS) elastance and resistance, k1 and k2 the linear and the nonlinear RS resistive coefficients, and PE the end-expiratory pressure. The models goodness of fit to the data was evaluated by the root mean square difference of predicted minus measured Pao values. Results: NRF data fit both models well at all PEEPe levels. ARDS and particularly COPD data fit the nonlinear model better. Values of k2 were often negative in COPD and ARDS groups, and they increased in parallel with PEEPe. A gradual increase in PEEPe resulted in better fit of ARDS and COPD data to both models. Conclusions: The model of V′ dependence of resistance is more suitable for the ARDS and particularly the COPD groups. PEEP tends to diminish the V′ dependence of respiratory resistance during the respiratory cycle, particularly in the COPD group, probably through an indirect effect of the increased lung volume.

Ashtrays and Signage as Determinants of a Smoke-Free Legislation’s Success

Introduction Successful smoke-free legislation is dependent on political will, enforcement and societal support. We report the success and pitfalls of a non-enforced nationwide smoke-free legislation in Greece, as well as ways in which compliance and enforcement-related factors, including ashtrays and signage, may impact indoor secondhand smoke (SHS) concentrations. Methods A follow-up study of venues (n = 150, at baseline, n = 75 at 2-year follow-up) in Greece assessed indoor particulate matter with a diameter less than 2.5 micrometers (PM2.5) concentrations attributable to SHS smoke every six months for two years (n = 455 venue/measurements). Results Following the implementation of the 2010 smoke-free legislation, mean PM2.5 concentrations attributable to SHS fell from 175.3 µg/m3 pre-ban to 84.52 µg/m3 immediately post-ban, increasing over subsequent waves (103.8 µg/m3 and 158.2 µg/m3 respectively). Controlling for potential influential factors such as ventilation, time of day, day of week, city and venue type, all post-ban measurements were still lower than during the pre-ban period (Wave 2 beta: −118.7, Wave 3 beta: −87.6, and Wave 4 beta: −69.9). Outdoor or indoor signage banning smoking was not found to affect SHS concentrations (beta: −10.9, p = 0.667 and beta: −18.1, p = 0.464 respectively). However, ashtray or ashtray equivalents were strong determinants of the existence of indoor SHS (beta: +67 µg/m3, p = 0.017). Conclusions While the public may be supportive of smoke-free legislation, adherence may decline rapidly if enforcement is limited or nonexistent. Moreover, enforcement agencies should also focus on the comprehensive removal of ashtray equivalents that could act as cues for smoking within a venue.

Suckling Rat Brain Regional Distribution of Acetylcholinesterase Activity in Galactosaemia In Vitro

We aimed to evaluate the effect of in vitro galactosaemia on acetylcholinesterase (AChE) activity in different suckling rat brain regions. Various concentrations of galactose (Gal), galactose-1-phosphate (Gal-1-P) and/or galactitol (Galtol) were preincubated for 1 h with homogenates from frontal cortex, hippocampus and for 1–3 h with hypothalamus homogenates at 37∘C. AChE activity was determined spectrophotometrically. Mixture A {Gal-1-P (2 mM), Galtol (2 mM), and Gal (4 mM) (=brain concentrations in classical galactosaemia)} or mixture B {Galtol (2 mM) and Gal (1 mM) (=brain concentrations in galactokinase deficiency galactosaemia)} inhibited by 18–20% (P < 0.01) AChE activity in frontal cortex or hippocampus homogenates. Gal-1-P (2–8 mM) reduced AChE activity by 20% (P < 0.01) on frontal cortex and hippocampus homogenates. Galtol (2–8 mM) resulted in an AChE inhibition {20–22% (P < 0.01)} in hippocampus, 2 mM of the substance had the same effect (20%, P < 0.01) on frontal cortex, whereas higher concentrations (4–8 mM) failed to decrease the enzyme activity anymore. Gal (1–8 mM) did not change AChE activity in the studied areas. Additionally, the hypothalamus enzyme activity was measured considerably high and remained unaltered in the presence of the above compounds. In conclusion, AChE activity was significantly higher in hypothalamus compared with those in frontal cortex and hippocampus. Frontal cortex and hippocampus AChE was significantly inhibited by Gal derivatives, whereas hypothalamus AChE activity remained unaltered possibly due to the histologically different innervation of this area.

The recent and projected public health and economic benefits of cigarette taxation in Greece

Objectives Greece is in an economic crisis compounded by the costs caused by smoking. The present investigation estimates the economic and public health benefits ensuing from the recent cigarette excise tax increase in 2011 and projects the potential benefits from an additional €2.00 per pack cigarette tax increase. Methods The effects of the recent cigarette excise tax increase were calculated on outcome measures: total price per pack, including specific excise, ad valorem tax, and value-added tax consumption; tax revenue; and per capita consumption of cigarettes. Additionally, smoking-attributable mortality, years of potential life lost, and productivity losses were estimated. Projected effects of an additional €2.00 per pack tax increase on consumption and tax revenue were also assessed. Results The cigarette excise tax increase in 2011 created €558 million in new tax revenue. Cigarette consumption reached a recent low of 24.9 billion sticks sold or 2197 sticks per person in 2011, indicating a 16% decrease in per capita cigarette consumption from the previous year. An additional €2.00 per pack increase in Greek cigarette taxes is projected to result in reduced cigarette sales by an additional 20% and lead to an increase in total cigarette tax revenues by nearly €1.2 billion and the prevention of 192 000 premature deaths. Conclusions Nations such as Greece, should employ taxation as a crucial measure to promote public health and economic development in such dire times. International economic organisations should aggressively pursue programmes and policies that champion the economic benefits of tobacco taxation.