Michael Tamm

Universitätsspital Basel, Bâle, Basel-City, Switzerland

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Publications (306)1580.21 Total impact

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    ABSTRACT: This is the experience with the Stratos system in two surgical centres for the management of two types of rib fractures: flail chest and multiple dislocated rib fractures with significant chest wall deformity.
    European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 09/2014; · 2.40 Impact Factor
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    ABSTRACT: Background: Existing prediction models for mortality in chronic obstructive pulmonary disease (COPD) patients have not yet been validated in primary care, which is where the majority of patients receive care. Objectives: Our aim was to validate the ADO (age, dyspnoea, airflow obstruction) index as a predictor of 2-year mortality in 2 general practice-based COPD cohorts. Methods: Six hundred and forty-six patients with COPD with GOLD (Global Initiative for Chronic Obstructive Lung Disease) stages I-IV were enrolled by their general practitioners and followed for 2 years. The ADO regression equation was used to predict a 2-year risk of all-cause mortality in each patient and this risk was compared with the observed 2-year mortality. Discrimination and calibration were assessed as well as the strength of association between the 15-point ADO score and the observed 2-year all-cause mortality. Results: Fifty-two (8.1%) patients died during the 2-year follow-up period. Discrimination with the ADO index was excellent with an area under the curve of 0.78 [95% confidence interval (CI) 0.71-0.84]. Overall, the predicted and observed risks matched well and visual inspection revealed no important differences between them across 10 risk classes (p = 0.68). The odds ratio for death per point increase according to the ADO index was 1.50 (95% CI 1.31-1.71). Conclusions: The ADO index showed excellent prediction properties in an out-of-population validation carried out in COPD patients from primary care settings. © 2014 S. Karger AG, Basel.
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    ABSTRACT: Long acting β2-agonists (LABA) have been reported to modify the extracellular matrix (ECM) composition in the airway wall. Based on our earlier studies we here investigated the mechanism underlying the control of ECM modification by LABA in primary human airway smooth muscle cells. Cells were treated with formoterol or salmeterol (30minutes) before TGF-β1 stimulation (2-3 days) Using RT-PCT, immuno-blotting and ELISA the de novo synthesis and deposition of collagen type-I, -III, -IV and fibronectin were determined. Matrix metalloproteinases (MMP)-2 and -9 were analyzed by zymography. Both LABA activated cAMP and its corresponding transcription factor CREB within 60minutes and thus partly reduced TGF-β1-induced gene transcription of collagen type-I, -III, fibronectin and connective tissue growth factor (CTGF). The inhibitory effect of both LABA on collagen type-I and -III deposition involved a cAMP dependent mechanism, while the inhibitory effect of the two drugs on TGF-β1-induced fibronectin deposition and on CTGF secretion was independent of cAMP. Interestingly, none of the two LABA reduced CTGF-induced synthesis of collagen type-I or type-III deposition. In addition, none of the two LABA modified collagen type-IV deposition or the expression and activity of MMP-2 or MMP-9. Our results show that LABA can prevent de novo deposition of specific ECM components through cAMP dependent and independent signaling. However, they do not reduce all ECM components by the same mechanism and they do not reduce existing collagen deposits. This might explain some of the controversial reports on the anti-remodeling effect of LABA in chronic inflammatory lung diseases.
    Biochemical pharmacology. 08/2014;
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    ABSTRACT: Chronic obstructive pulmonary disease (COPD) is a complex disease with various phenotypes. The simultaneous determination of multiple biomarkers reflecting different pathobiological pathways could be useful in identifying individuals with an increased risk of death. We derived and validated a combination of three biomarkers (adrenomedullin, arginine vasopressin and atrial natriuretic peptide), assessed in plasma samples of 385 patients, to estimate mortality risk in stable COPD. Biomarkers were analysed in combination and defined as high or low. In the derivation cohort (n = 142), there were 73 deaths during the 5-year follow-up. Crude hazard ratios for mortality were 3.0 (95% CI 1.8-5.1) for one high biomarker, 4.8 (95% CI 2.4-9.5) for two biomarkers and 9.6 (95% CI 3.3-28.3) for three high biomarkers compared with no elevated biomarkers. In the validation cohort (n = 243), 87 individuals died. Corresponding hazard ratios were 1.9 (95% CI 1.1-3.3), 3.1 (95% CI 1.8-5.4) and 5.4 (95% CI 2.5-11.4). Multivariable adjustment for clinical variables as well as the BODE (body mass index, airflow obstruction, dyspnoea, exercise capacity) index and stratification by the Global Initiative for Chronic Obstructive Lung Disease stages provided consistent results. The addition of the panel of three biomarkers to the BODE index generated a net reclassification improvement of 57.9% (95% CI 21.7-92.4%) and 45.9% (95% CI 13.9-75.7%) at 3 and 5 years, respectively. Simultaneously elevated levels of adrenomedullin, arginine vasopressin and atrial natriuretic peptide are associated with increased risk of death in patients with stable COPD.
    The European respiratory journal. 07/2014;
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    ABSTRACT: Rationale: Invasive fungal disease (IFD) is a significant cause of morbidity and mortality in immunocompromised patients. Objectives: We hypothesize that galactomannan, a component of fungal cell wall, as measured in the bronchoalveolar lavage (BAL-GM) might be a diagnostic adjunct in hematological malignancies. Methods: 568 hematological cases undergoing diagnostic bronchoscopy due to respiratory symptoms and/or suspected IFD between 2009 and 2013 at a tertiary care center in Switzerland were included in this prospective, observational cohort study. We compared accuracy of the BAL-GM ELISA determination in predicting IFD as classified by the EORTC/MSG definition. Measurements and Main Results: BAL-GM was positive in 155 cases (29.2%). According to the EORTC/MSG criteria, IFD was classified as possible in 182 (34.3%), probable in 45 (8.5%) and proven 6 (1.1%). BAL-GM provided 50% sensitivity, 73.0% specificity, 16% PPV, and 93% NPV for diagnosing proven+probable IFD. Results were similar when antifungal treatment and radiologic suspicion of IFD were used as the gold standard. The AUC of the ROC curve (AUC) for the diagnosis of proven+probable IFD was 0.716 (95%CI 0.638-0.794, p<0.001). Conclusions: Galactomannan in the BAL had modest agreement with EORTC/MSG criteria for diagnosing invasive fungal disease in immunocompromised patients with a high degree of antifungal exposure.
    American Journal of Respiratory and Critical Care Medicine 07/2014; · 11.04 Impact Factor
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    ABSTRACT: Background: Hypoxemia is a surrogate marker for periprocedural endoscopic complications. There are no data comparing the safety of propofol sedation with another sedative regimen in medical thoracoscopy. Objective: To evaluate whether sedation with propofol is as safe and effective as sedation with midazolam. Methods: Ninety consecutive patients undergoing medical thoracoscopy were randomly allocated to receive either intravenous propofol or midazolam. Predefined periprocedural complications included hypoxemia, hypotension, bleeding, need for airway insertion, mechanical ventilation, intensive care unit transfer and death. The primary endpoint was the mean lowest oxygen saturation during the procedure. Results: Randomized groups had similar demographics (64 ± 16 years, 57% male, 91% American Society of Anesthesiologists class III-IV) and a balanced distribution of procedures. The mean lowest oxygen saturation during the procedure was significantly lower in the propofol group as compared to the midazolam group (93 ± 6 vs. 96 ± 3%, p = 0.007). Patients randomized to propofol showed more episodes of hypoxemia (27 vs. 4%, p = 0.007) and hypotension (82 vs. 40%, p < 0.0001). No procedure had to be aborted. None of the patients required an artificial airway, mechanical ventilation or intensive care unit care, and none died. Conclusions: As assessed by the surrogate marker hypoxemia, propofol should not be considered the first choice for sedation in medical thoracoscopy. © 2014 S. Karger AG, Basel.
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    ABSTRACT: The fully human anti-lipopolysaccharide (LPS) immunoglobulin M (IgM) monoclonal antibody panobacumab was developed as an adjunctive immunotherapy for the treatment of O11 serotype Pseudomonas aeruginosa infections. We evaluated the potential clinical efficacy of panobacumab in the treatment of nosocomial pneumonia. We performed a post-hoc analysis of a multicenter phase IIa trial (NCT00851435) designed to prospectively evaluate the safety and pharmacokinetics of panobacumab. Patients treated with panobacumab (n = 17), including 13 patients receiving the full treatment (three doses of 1.2 mg/kg), were compared to 14 patients who did not receive the antibody. Overall, the 17 patients receiving panobacumab were more ill. They were an average of 72 years old [interquartile range (IQR): 64-79] versus an average of 50 years old (IQR: 30-73) (p = 0.024) and had Acute Physiology and Chronic Health Evaluation II (APACHE II) scores of 17 (IQR: 16-22) versus 15 (IQR: 10-19) (p = 0.043). Adjunctive immunotherapy resulted in an improved clinical outcome in the group receiving the full three-course panobacumab treatment, with a resolution rate of 85 % (11/13) versus 64 % (9/14) (p = 0.048). The Kaplan-Meier survival curve showed a statistically significantly shorter time to clinical resolution in this group of patients (8.0 [IQR: 7.0-11.5] versus 18.5 [IQR: 8-30] days in those who did not receive the antibody; p = 0.004). Panobacumab adjunctive immunotherapy may improve clinical outcome in a shorter time if patients receive the full treatment (three doses). These preliminary results suggest that passive immunotherapy targeting LPS may be a complementary strategy for the treatment of nosocomial O11 P. aeruginosa pneumonia.
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    ABSTRACT: The prevalence of exertional hypoxemia in unselected COPD patients is unknown. Intermittent hypoxia leads to adrenomedullin (ADM) up regulation through the HIF-1 pathway. We aimed to assess the prevalence and the annual probability to develop exertional hypoxemia in stable COPD. We also hypothesized that increased ADM might be associated with exertional hypoxemia and envisioned that adding ADM to clinical variables might improve its prediction in COPD. 1233 6-minute walking tests and circulating proadrenomedullin levels from 574 patients with clinically stable, moderate to very severe COPD enrolled in a multinational cohort study and followed-up for 2 years were concomitantly analyzed. The prevalence of exertional hypoxemia was 29.1%. In a matrix derived from a fitted-multi-state model, the annual probability to develop exertional hypoxemia was 21.6%. Exertional hypoxemia was associated with greater deterioration of specific domains of health-related QoL, higher severe exacerbation and death annual rates. In the logistic linear and conditional Cox-regression multivariable analyses, both FEV1% predicted and proADM proved independent predictors of exertional hypoxemia (p<0.001 for both). Adjustment for comorbidities, including cardiovascular disorders, and exacerbation-rate did not influence results. Relative to using FEV1% pred alone, adding proADM resulted in a significant improvement of the predictive properties (p=0.018). Based on the suggested non-linear nomogram, patients with moderate COPD (FEV1 predicted=50%) but high proADM levels (>2nmol/l) presented increased risk (>30%) for exertional desaturation. Exertional desaturation is common and associated with poorer clinical outcomes in COPD. Adrenomedullin improves prediction of exertional desaturation as compared to the use of FEV1%pred alone.
    Chest 04/2014; · 5.85 Impact Factor
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    ABSTRACT: B-cells in airways and lung parenchyma may be involved in COPD evolution. However, whether their pathogenic role is beneficial or harmful remains controversial. The objective of this study was to investigate the maturation of adenovirus-specific immunoglobulins in COPD patients in respect to clinical outcome. The presence of adenovirus-specific immunoglobulins during acutely exacerbated COPD (AECOPD) was analyzed at exacerbation and 2-3 weeks later. Patients with detectable adenovirus-specific IgM and low IgG avidity were grouped into fast and delayed IgG maturation. The clinical outcome of both groups was evaluated. Out of 208 patients, 43 patients (20.7%) had serologic evidence of recent adenovirus infection and were grouped into 26 patients with fast IgG maturation and 17 patients with delayed IgG maturation. Baseline characteristics, AECOPD therapy, and duration of hospitalization were similar in both groups. However, the AECOPD recurrence rate within six months was higher (p = 0.003) and there was a trend for earlier AECOPD related re-hospitalizations (p = 0.061) in patients with delayed IgG maturation. The time to re-hospitalization or death within two years was shorter in patients with delayed IgG maturation (p = 0.003). Adenovirus-specific IgG maturation was an independent predictor of both, the number of recurrent AECOPDs within six months (p = 0.001) and the occurrence of hospitalization or death within two years (p = 0.005). Delayed immunoglobulin avidity maturation, following COPD exacerbation, is associated with worse outcome.
    Chest 04/2014; · 5.85 Impact Factor
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    ABSTRACT: Diffuse alveolar hemorrhage (DAH) is a life-threatening condition requiring urgent treatment. There are many different treatment-relevant causes of DAH, making the diagnostic approach to these patients complex and necessitating a multidisciplinary team. We report the case of a kidney transplant recipient in whom all diagnostic efforts did not reveal the cause of DAH, and only autopsy was able to establish an unexpected diagnosis. © 2014 S. Karger AG, Basel.
    Respiration 04/2014; · 2.62 Impact Factor
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    ABSTRACT: To the Editor:The course of sarcoidosis is heterogeneous, and the assessment of pulmonary and extrathoracic organ involvement is important for clinical treatment decisions (1). Whole-body imaging techniques have been evaluated to assess total disease activity (2, 3). (18)F-fluoro-2-deoxy-d-glucose positron emission tomography ((18)FDG-PET) and (18)FDG-PET/computed tomography (CT) allow a complete picture of active intra- and extrapulmonary sites (4). Whole-body magnetic resonance imaging (WB-MRI) is an established diagnostic tool for multifocal disorders such as multiple myeloma and metastatic diseases (5, 6). The role of WB-MRI in the assessment of extrathoracic organ involvement in patients with sarcoidosis has not yet been studied.We present an institutional review board-approved study including 24 patients with histologically confirmed sarcoidosis. Patients were recruited regardless of treatment, apparent extrapulmonary involvement and symptoms; written informed consent was obtained. To estimate extrapulmonary disease activity, the extrapulmonary physician organ severity tool (ePOST) was employed (7), scoring 17 organs (0: not affected; 6: very severely affected). Pulmonary function tests (PFTs) and serum levels of angiotensin-converting enzyme (ACE) and soluble interleukin-2 receptor (sIL-2R) were assessed. All subjects underwent WB-MRI on a clinical 1.5-T whole-body scanner with an 18-channel coil array system (Magnetom Avanto (Tim); Siemens Medical Solutions, Erlangen, Germany). The acquisition consisted of the following.
    European Respiratory Journal 03/2014; · 6.36 Impact Factor
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    ABSTRACT: Pseudomonas aeruginosa frequently causes nosocomial pneumonia and is associated with poor outcome. The purpose of this study was to assess the prevalence and clinical outcome of nosocomial pneumonia caused by serotype specific Pseudomonas aeruginosa in critically ill patients under appropriate antimicrobial therapy management. A retrospective, non-interventional epidemiological multicenter cohort study involving 143 patients with confirmed nosocomial pneumonia caused by Pseudomonas aeruginosa. Patients were analyzed for a period of 30 days from time of nosocomial pneumonia onset. Fourteen patients fulfilling the same criteria from a Phase IIa study conducted at the same time/centers were included in the prevalence calculations but not in the clinical outcome analysis. The prevalence of serotypes was: O6 (29%), O11 (23%), O10 (10%), O2 (9%) and O1 (8%). Serotypes with a prevalence < 5% were found in 13% of patients, 8% were classified as not typeable. Across all serotypes there was 19% mortality, 70% clinical resolution, 11% clinical continuation and 5% clinical recurrence. Age and higher APACHE II were predictive risk factors associated with probability of death and lower clinical resolution for Pseudomonas aeruginosa nosocomial pneumonia. Mortality tends to be higher with O1 (40%) and lower with O2 (0%); clinical resolution tends to be better with O2 (82%) compared to other serotypes. Persisting pneumonia with O6 and O11 was respectively 8% and 21%; clinical resolution with O6 and O11 was respectively 75% and 57%. In Pseudomonas aeruginosa nosocomial pneumonia, the most prevalent serotypes were O6 and O11. Further studies including larger group sizes are needed to correlate clinical outcome with virulence factors of Pseudomonas aeruginosa in patients with nosocomial pneumonia caused by various serotypes; and to compare O6 and O11, the 2 serotypes most frequently encountered in critically ill patients.
    Critical care (London, England) 01/2014; 18(1):R17. · 4.72 Impact Factor
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    ABSTRACT: Background. Bronchial smooth muscle cells (BSMC) are a major source of proinflammatory and proangiogenic cytokines and chemokines, including VEGF and CXC-chemokines. CXC-chemokines act primarily on neutrophils, mediating their recruitment to and activation at the site of inflammation. In humans, house-dust mite (HDM) allergens can cause asthmatic exacerbations and trigger an inflammatory response through protease-dependent mechanisms. Objective. We investigated the effect HDM extract on the release of pro-angiogenic and proinflammatory cytokines from BSMC. Methods. Human primary BSMC were stimulated with HDM extract in the absence or presence of fetal calf serum (FCS). Twenty angiogenic cytokines were detected by a specific antibody array and modified protein levels were confirmed by ELISA. Neutrophil migration was measured using a 96-well Boyden chamber. Results. ENA-78/CXCL5 protein levels in conditioned medium of BSMC stimulated with HDM extract were significantly reduced (n = 10, P < 0.05) but restored in the presence of 5% FCS. HDM extracts did not affect ENA-78/CXCL5 mRNA levels. Recombinant ENA-78/CXCL5 was degraded after incubation with HDM extracts (n = 7, P < 0.05) but restored after the addition of the serine protease AEBSF. Neutrophil migration towards recombinant ENA-78/CXCL5 was also reduced in the presence of HDM extract. Conclusion. HDM proteases degrade ENA-78/CXCL5. Thus exposure to HDM allergens may alter ENA-78/CXCL5 levels in the lungs and may affect angiogenesis and the inflammatory response in the airways of asthma patients.
    Journal of allergy. 01/2014; 2014:673673.
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    ABSTRACT: Rapid and accurate risk stratification in patients with community-acquiredpneumonia (CAP) is an unmet clinical need. Cortisol to dehydroepiandrosterone (DHEA)ratio was put forward as a prognostic marker in sepsis. We herein validatedthe prognostic value of the adrenal hormones DHEA, DHEA-Sulfate (DHEAS),cortisol/DHEA-, cortisol/DHEAS- and DHEA/DHEAS -ratios in patients with CAP.
    PLoS ONE 01/2014; 9(6):e99518. · 3.53 Impact Factor
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    ABSTRACT: For oxygen supply, airway wall cells depend on diffusion though the basement membrane, as well as on delivery by micro-vessels. In the asthmatic lung, local hypoxic conditions may occur due to increased thickness and altered composition of the basement membrane, as well as due to edema of the inflamed airway wall. In our study we investigated the effect of hypoxia on proliferation and pro-inflammatory and pro-angiogenic parameter production by human bronchial smooth muscle cells (BSMC). Furthermore, conditioned media of hypoxia-exposed BSMC was tested for its ability to induce sprout outgrowth from endothelial cells spheroids. BSMC were cultured in RPMI1640 (5% FCS) under normoxic (21% O2) and hypoxic (1% and 5% O2) conditions. Proliferation was determined by cell count and Western blot analysis for cyclin E and Proliferating Cell Nuclear Antigen (PCNA). Secretion of IL-6, IL-8, ENA-78 and VEGF-A was analyzed by ELISA. BSMC conditioned medium was tested for its angiogenic capacity by endothelial cell (EC)-spheroid in vitro angiogenesis assay. Proliferation of BSMC obtained from asthmatic and non-asthmatic patients was significantly reduced in the presence of 1% O2, whereas 5% O2 reduced proliferation of asthmatic BSMC only. Hypoxia induced HIF-1α expression in asthmatic and non-asthmatic BSMC, which coincided with significantly increased release of IL-6, IL-8 and VEGF-A, but not ENA-78. Finally, endothelial sprout outgrowth from EC spheroids was increased when exposed to hypoxia conditioned BSMC medium. Hypoxia had dualistic effects on proliferative and inflammatory responses of asthmatic and non-asthmatic BSMC. First, hypoxia reduced BSMC proliferation. Second, hypoxia induced a pro-inflammatory, pro-angiogenic response. BSMC and EC may thus be promising new targets to counteract and/or alleviate airway wall remodeling.
    PLoS ONE 01/2014; 9(2):e89875. · 3.53 Impact Factor
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    ABSTRACT: Reactive oxygen species (ROS) have been implemented in the etiology of pulmonary fibrosis (PF) in systemic sclerosis. In the bleomycin model, we evaluated the role of acquired mutations in mitochondrial DNA (mtDNA) and respiratory chain defects as a trigger of ROS formation and fibrogenesis. Adult male Wistar rats received a single intratracheal instillation of bleomycin and their lungs were examined at different time points. Ashcroft scores, collagen and TGFβ1 levels documented a delayed onset of PF by day 14. In contrast, increased malon dialdehyde as a marker of ROS formation was detectable as early as 24 hours after bleomycin instillation and continued to increase. At day 7, lung tissue acquired significant amounts of mtDNA deletions, translating into a significant dysfunction of mtDNA-encoded, but not nucleus-encoded respiratory chain subunits. mtDNA deletions and markers of mtDNA-encoded respiratory chain dysfunction significantly correlated with pulmonary TGFβ1 concentrations and predicted PF in a multivariate model.
    Scientific reports. 01/2014; 4:5336.
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    ABSTRACT: Mesenchymal cells (fibroblasts) of the airway wall respond to cholinergic stimulation by releasing pro-inflammatory and chemotactic cytokines and may thus contribute to chronic inflammation of the lung. Here, we studied the anti-inflammatory potential of olodaterol, a long acting β2-adrenergic receptor agonist, and tiotropium, a long-acting muscarinic receptor antagonist, and whether they interact at the level of the cyclic AMP dependent signaling pathway. Pulmonary fibroblasts of asthmatic (n=9) and non-asthmatic (n=8) subjects were stimulated with the muscarinic receptor agonist carbachol and interleukin-1β (IL-1 beta) in presence or absence of tiotropium or olodaterol alone, or their combination.. We also measured cAMP levels and phosphorylation of the cAMP response element binding protein (CREB). As single components, carbachol, olodaterol and tiotropium did not affect IL-6 and IL-8 release. Carbachol concentration-dependently enhanced the production of IL-1β-induced IL-6 and IL-8, which was blocked by the simultaneous addition of tiotropium. The combination of olodaterol plus tiotropium further reduced IL-6 and IL-8 release. Olodaterol induced cAMP and the phosphorylation of CREB, an effect counteracted by carbachol, but rescued by tiotropium. We conclude that olodaterol plus tiotropium cooperate to decrease the inflamamtory response in pulmonary fibroblasts in vitro.
    Pulmonary Pharmacology &amp Therapeutics 11/2013; · 2.54 Impact Factor
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Publication Stats

6k Citations
1,580.21 Total Impact Points


  • 1995–2014
    • Universitätsspital Basel
      • Klinik für Infektiologie & Spitalhygiene
      Bâle, Basel-City, Switzerland
    • University of Vienna
      • Department of Internal Medicine III
      Vienna, Vienna, Austria
  • 2009–2013
    • Kantonsspital St. Gallen
      San Gallo, Saint Gallen, Switzerland
  • 1999–2013
    • Universität Basel
      • Department of Biomedicine
      Bâle, Basel-City, Switzerland
  • 2000–2012
    • Aristotle University of Thessaloniki
      • Β' Εργαστήριο Φαρμακολογίας
      Thessaloníki, Kentriki Makedonia, Greece
  • 2007
    • University of Massachusetts Medical School
      Worcester, Massachusetts, United States
  • 2006
    • University of Groningen
      • Department of Pathology and Medical Biology
      Groningen, Province of Groningen, Netherlands
  • 2004–2006
    • Woolcock Institute of Medical Research
      Sydney, New South Wales, Australia
    • Inselspital, Universitätsspital Bern
      Berna, Bern, Switzerland
    • University of Sydney
      • Respiratory Research Group
      Sydney, New South Wales, Australia
    • Singapore General Hospital
      • Department of Respiratory and Critical Care Medicine
      Tumasik, Singapore
  • 2001–2005
    • St. Vincent's Hospital Sydney
      Sydney, New South Wales, Australia
    • University of Helsinki
      • Department of Virology
      Helsinki, Province of Southern Finland, Finland
    • Yale University
      New Haven, Connecticut, United States
    • Yale-New Haven Hospital
      • Department of Pathology
      New Haven, Connecticut, United States
  • 2003
    • St. Vincent Hospital
      Green Bay, Wisconsin, United States
    • Saint Vincent Hospital
      Worcester, Massachusetts, United States
  • 2002
    • University of Leipzig
      Leipzig, Saxony, Germany
    • St Vincent’s Private Hospital (Australia)
      Sydney, New South Wales, Australia
  • 1997
    • Universitätsklinikum Freiburg
      Freiburg an der Elbe, Lower Saxony, Germany