Alan Altraja
University of Tartu
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Featured researches published by Alan Altraja.
The Lancet Respiratory Medicine | 2017
Noel G. McElvaney; Jonathan Burdon; Mark Holmes; Allan R. Glanville; Peter Wark; Philip J. Thompson; Paul Hernandez; Jan Chlumsky; Helmut Teschler; Joachim H. Ficker; Niels Seersholm; Alan Altraja; Riitta Mäkitaro; Joanna Chorostowska-Wynimko; Marek Sanak; Paul I Stoicescu; Eeva Piitulainen; Oliver Vit; Marion Wencker; Michael A. Tortorici; Michael Fries; Jonathan Edelman; Kenneth R. Chapman
BACKGROUND Purified α1 proteinase inhibitor (A1PI) slowed emphysema progression in patients with severe α1 antitrypsin deficiency in a randomised controlled trial (RAPID-RCT), which was followed by an open-label extension trial (RAPID-OLE). The aim was to investigate the prolonged treatment effect of A1PI on the progression of emphysema as assessed by the loss of lung density in relation to RAPID-RCT. METHODS Patients who had received either A1PI treatment (Zemaira or Respreeza; early-start group) or placebo (delayed-start group) in the RAPID-RCT trial were included in this 2-year open-label extension trial (RAPID-OLE). Patients from 22 hospitals in 11 countries outside of the USA received 60 mg/kg per week A1PI. The primary endpoint was annual rate of adjusted 15th percentile lung density loss measured using CT in the intention-to-treat population with a mixed-effects regression model. This trial is registered with ClinicalTrials.gov, number NCT00670007. FINDINGS Between March 1, 2006, and Oct 13, 2010, 140 patients from RAPID-RCT entered RAPID-OLE: 76 from the early-start group and 64 from the delayed-start group. Between day 1 and month 24 (RAPID-RCT), the rate of lung density loss in RAPID-OLE patients was lower in the early-start group (-1·51 g/L per year [SE 0·25] at total lung capacity [TLC]; -1·55 g/L per year [0·24] at TLC plus functional residual capacity [FRC]; and -1·60 g/L per year [0·26] at FRC) than in the delayed-start group (-2·26 g/L per year [0·27] at TLC; -2·16 g/L per year [0·26] at TLC plus FRC, and -2·05 g/L per year [0·28] at FRC). Between months 24 and 48, the rate of lung density loss was reduced in delayed-start patients (from -2·26 g/L per year to -1·26 g/L per year), but no significant difference was seen in the rate in early-start patients during this time period (-1·51 g/L per year to -1·63 g/L per year), thus in early-start patients the efficacy was sustained to month 48. INTERPRETATION RAPID-OLE supports the continued efficacy of A1PI in slowing disease progression during 4 years of treatment. Lost lung density was never recovered, highlighting the importance of early intervention with A1PI treatment. FUNDING CSL Behring.
Chest | 2005
Lea Pehme; Vahur Hollo; Mati Rahu; Alan Altraja
STUDY OBJECTIVES To characterize the incidence of extrapulmonary tuberculosis (EPTB) in Estonia, by site and age, in conditions of marked pulmonary tuberculosis (TB) increase, ie, during the period of fundamental societal changes, but where TB incidence has not been influenced by HIV infection. DESIGN AND SETTING A retrospective study. PATIENTS All new cases of EPTB (n = 622) detected in Estonia from 1991 to 2000. RESULTS The incidence of pulmonary TB in Estonia increased from 21.5 in 1991 to 44.6/100,000 in 2000. In contrast, the incidence of EPTB did not increase at the same pace, changing only from 3.6 in 1991 to 4.7/100,000 in 2000. The increase in the incidence of EPTB was significantly lower than that of pulmonary TB (p < 0.05), and the relative frequency of EPTB among overall TB steadily decreased from 17.0% in 1991 to 10.1% in 2000. The incidence of EPTB forms with a long latency period (eg, osteoarticular and urogenital TB) remained unchanged, while that of EPTB forms with a short latency period (eg, intrathoracic lymph node TB) increased (p < 0.05). The number of cases of urogenital, pleural, and osteoarticular TB increased with age; the number of cases of intrathoracic lymph node TB decreased with age. The bacteriologic confirmation rate was lower in EPTB than in pulmonary TB and varied according to site. CONCLUSION There was no increase in the incidence of EPTB during 10 years despite the dramatic increase in overall TB. The proportion of EPTB among all TB tended to decrease with increasing age, and different EPTB sites prevailed in different age groups.
Respiratory Research | 2008
Siiri Altraja; Martin Kadai; Erki Rekker; Alan Altraja
BackgroundCysteinyl leukotrienes (CysLTs) are key mediators of asthma, but their role in the genesis of airway remodeling is insufficiently understood. Recent evidence suggests that increased expression of tenascin (Tn) and laminin (Ln) β2 chain is indicative of the remodeling activity in asthma, but represents also an example of deposition of extracellular matrix, which affects the airway wall compliance. We tested the hypothesis that CysLTs affect production of Tn and Ln β2 chain by human bronchial epithelial cells and elucidated, which of the CysLT receptors, CysLT1 or CysLT2, mediate this effect.MethodsCultured BEAS-2B human bronchial epithelial cells were stimulated with leukotriene D4 (LTD4) and E4 (LTE4) and evaluated by immunocytochemistry, Western blotting, flow cytometry, and RT-PCR. CysLT receptors were differentially blocked with use of montelukast or BAY u9773.ResultsLTD4 and LTE4 significantly augmented the expression of Tn, whereas LTD4, distinctly from LTE4, was able to increase also the Ln β2 chain. Although the expression of CysLT2 prevailed over that of CysLT1, the up-regulation of Tn and Ln β2 chain by CysLTs was completely blocked by the CysLT1-selective antagonist montelukast with no difference between montelukast and the dual antagonist BAY u9773 for the inhibitory capacity.ConclusionThese findings suggest that the CysLT-induced up-regulation of Tn and Ln β2 chain, an important epithelium-linked aspect of airway remodeling, is mediated predominantly by the CysLT1 receptor. The results provide a novel aspect to support the use of CysLT1 receptor antagonists in the anti-remodeling treatment of asthma.
PLOS ONE | 2015
Argo Aug; Siiri Altraja; Kalle Kilk; Rando Porosk; Ursel Soomets; Alan Altraja
E-cigarettes are widely believed to be safer than conventional cigarettes and have been even suggested as aids for smoking cessation. However, while reasonable with some regards, this judgment is not yet supported by adequate biomedical research data. Since bronchial epithelial cells are the immediate target of inhaled toxicants, we hypothesized that exposure to e-cigarettes may affect the metabolome of human bronchial epithelial cells (HBEC) and that the changes are, at least in part, induced by oxidant-driven mechanisms. Therefore, we evaluated the effect of e-cigarette liquid (ECL) on the metabolome of HBEC and examined the potency of antioxidants to protect the cells. We assessed the changes of the intracellular metabolome upon treatment with ECL in comparison of the effect of cigarette smoke condensate (CSC) with mass spectrometry and principal component analysis on air-liquid interface model of normal HBEC. Thereafter, we evaluated the capability of the novel antioxidant tetrapeptide O-methyl-l-tyrosinyl-γ-l-glutamyl-l-cysteinylglycine (UPF1) to attenuate the effect of ECL. ECL caused a significant shift in the metabolome that gradually gained its maximum by the 5th hour and receded by the 7th hour. A second alteration followed at the 13th hour. Treatment with CSC caused a significant initial shift already by the 1st hour. ECL, but not CSC, significantly increased the concentrations of arginine, histidine, and xanthine. ECL, in parallel with CSC, increased the content of adenosine diphosphate and decreased that of three lipid species from the phosphatidylcholine family. UPF1 partially counteracted the ECL-induced deviations, UPF1’s maximum effect occurred at the 5th hour. The data support our hypothesis that ECL profoundly alters the metabolome of HBEC in a manner, which is comparable and partially overlapping with the effect of CSC. Hence, our results do not support the concept of harmlessness of e-cigarettes.
Respirology | 2009
Siiri Altraja; Juta Jaama; Ervin Valk; Alan Altraja
Background and objective: Activated bronchial epithelial cells exert considerable potential to maintain a microenvironment in the airway wall that promotes airway inflammation and remodelling. Cysteinyl leucotrienes (CysLT) and transforming growth factor‐β1 (TGF‐β1) are both increased in asthmatic airways and may influence the pathophysiology of disease. However, the consequences of activation of bronchial epithelial cells by these mediators are not fully understood. A proteomic‐based approach was used to characterize the inflammatory pathways in bronchial epithelial cells after stimulation with CysLT and TGF‐β1.
Scandinavian Journal of Infectious Diseases | 2006
Lea Pehme; Kaja Rahu; Mati Rahu; Alan Altraja
The resurgence of tuberculosis (TB) in Estonia, a post-socialist Eastern European country, has coincided with delayed case detection suggested by increase in advanced forms of pulmonary tuberculosis among newly detected cases. We estimated the determinants of patient delay in conditions of negligible HIV infection, insignificant immigration and free access to medical care with TB. All newly-detected symptomatic culture-positive patients aged ≥16y with pulmonary TB from southern Estonia during 2002–2003 (n=185) were interviewed. Intervals greater than the median (79d) and the 75th percentile (140d) between onset of the first symptom and the first medical visit were defined as prolonged and extreme patient delay, respectively. Male gender was associated with both prolonged and extreme patient delay (OR 2.12; 95% CI 1.06–4.23 and OR 3.28; 95% CI 1.30–8.26, respectively), whereas rural residence was associated with prolonged patient delay (OR 2.08; 95% CI 1.06–4.08). Median patient delay was shortest when the first symptom was fever (22d) and greatest when it was cough with haemoptysis (196d). The study shows that even in absence of barriers in accessing health care, the median patient delay can be longer than in most former studies, whereas males and rural residents are at greater risk.
The Journal of Allergy and Clinical Immunology | 1996
Alan Altraja; Annika Laitinen; Sulev Meriste; Sirje Marran; Tiiu Märtson; Heinart Sillastu; Lauri A. Laitinen
Nedocromil sodium is recommended for daily treatment of mild persistent asthma but its effect on cellular changes in asthmatic airways is poorly understood. We compared the antiinflammatory effects of nedocromil sodium and albuterol in 32 patients with asthma who received either nedocromil sodium 4 mg or albuterol 0.2 mg four times daily for 12 weeks according to a double-blind protocol. Patients underwent fiberoptic bronchoscopy, and lung function and bronchial responsiveness to histamine were measured. Numbers of inflammatory cells were studied by immunohistochemistry and image analysis. We were unable to identify any statistical differences between treatment groups for any of the variables measured. We conclude that our immunohistochemical study does not support the concept of nedocromil sodium as a potent/antiinflammatory drug.
Clinical Respiratory Journal | 2016
Hille Lill; Kai Kliiman; Alan Altraja
Sarcoidosis is endemically prevalent in Northern Europe, but gender differences among the sarcoidosis population have not yet been compositely addressed.
American Journal of Respiratory Cell and Molecular Biology | 2014
Argo Aug; Alan Altraja; Siiri Altraja; Liisi Laaniste; Riina Mahlapuu; Ursel Soomets; Kalle Kilk
Human bronchial epithelial cells (HBECs) have first-line contact with harmful substances during smoking, and changes in their metabolism most likely represent a defining factor in coping with the stress and development of airway diseases. This study was designed to determine the dynamics of metabolome changes in HBECs treated with cigarette smoke condensate (CSC), and to test whether normal metabolism can be restored by synthetic antioxidants. Principal component analysis, based on untargeted mass spectra, indicated that treatment of CSC-exposed HBECs with O-methyl-L-tyrosinyl-γ-L-glutamyl-L-cysteinylglycine (UPF1) acted faster than did N-acetylcysteine to revert the effect of CSC. The maximum effect of 10 μg/ml CSC itself on HBEC cell line, BEAS-2B, metabolism was seen at 2 hours after treatment, with return to the baseline level by 7 hours. In primary HBECs, the initial maximum effect was seen at 1 hour after CSC exposure. Certain metabolites associated with redox pathways and energy production were affected by CSC. Subsequent restoration of their content by UPF1 supports the hypothetical protective capacity of UPF1 against the oxidative stress and increased energy demand, respectively. Furthermore, UPF1 up-regulated the contents of phospholipid species identified as phosphatidylcholines and phosphatidylethanolamines in the CSC-exposed HBECs, indicating possible suppression of inflammatory processes along with an increase in spermidine as an endogenous cytoprotector. In conclusion, with this dynamic metabolomics study, we characterize the durability of the CSC-induced metabolic changes in BEAS-2B line cells and primary HBECs, and demonstrate the ability of UPF1 to significantly accelerate the recovery of HBECs from CSC insult.
PLOS ONE | 2013
Ingrid Oit-Wiscombe; László Virág; Ursel Soomets; Alan Altraja
Chronic oxidative stress (OS), a major mechanism of chronic obstructive pulmonary disease (COPD), may cause significant damage to DNA. Poly(ADP-ribose) polymerase (PARP)-1 is rapidly activated by OS-induced DNA lesions. However, the degree of DNA damage along with the evolution of COPD is unclear. In peripheral blood mononuclear cells of non-smoking individuals, non-obstructive smokers, patients with COPD of all stages and those with COPD exacerbation, we evaluated DNA damage, PARP activity and PARP-1 mRNA expression using Comet Assay IV, biotinylated-NAD incorporation assay and qRT-PCR, respectively and subjected results to ordinal logistic regression modelling. Adjusted for demographics, smoking-related parameters and lung function, novel comet parameters, tail length/cell length ratio and tail migration/cell length ratio, showed the greatest increase along the study groups corresponding to the evolution of COPD [odds ratio (OR) 7.88, 95% CI 4.26–14.57; p<0.001 and OR 3.91, 95% CI 2.69–5.66; p<0.001, respectively]. Analogously, PARP activity increased significantly over the groups (OR = 1.01; 95%; p<0.001). An antioxidant tetrapeptide UPF17 significantly reduced the PARP-1 mRNA expression in COPD, compared to that in non-obstructive individuals (p = 0.040). Tail length/cell length and tail migration/cell length ratios provide novel progression-sensitive tools for assessment of DNA damage. However, it remains to be elucidated whether inhibition of an elevated PARP-1 activity has a safe enough potential to break the vicious cycle of the development and progression of COPD.