Differential radiological features of patients infected or colonised with slow-growing non-tuberculous mycobacteria.

Non-tuberculous mycobacterial pulmonary disease (NTM-PD) is considered a growing health concern. The majority of NTM-PD cases in Europe are caused by slow-growing mycobacteria (SGM). However, distinct radiological features of different SGM remain largely uninvestigated. We applied a previously described radiological score to a patient cohort consisting of individuals with isolation of different SGM. Correlations between clinical data, species and computed tomography (CT) features were examined by logistic and linear regression analyses, as well as over the course of time. Overall, 135 pulmonary CT scans from 84 patients were included. The isolated NTM-species were mainly Mycobacterium avium complex (MAC, n = 49), as well as 35 patients with non-MAC-species. Patients with isolation of M. intracellulare had more extensive CT findings compared to all other SGM species (coefficient 3.53, 95% Cl - 0.37 to 7.52, p = 0.075) while patients meeting the ATS criteria and not undergoing therapy exhibited an increase in CT scores over time. This study provides insights into differential radiological features of slow-growing NTM. While M. intracellulare exhibited a tendency towards higher overall CT scores, the radiological features were similar across different SGM. The applied CT score might be a useful instrument for monitoring patients and could help to guide antimycobacterial therapy.

Endothelin-1 enhances ß2-adrenoceptor gene transcription in human lung fibroblasts.

AIMS: The present study aimed to explore possible effects of endothelin-1 (ET-1) on ß(2)-adrenoceptor gene transcription in human lung fibroblasts. MAIN METHODS: MRC-5 human lung fibroblasts were cultured in absence or presence of test substances, followed by ß(2)-adrenoceptor mRNA determination by quantitative real time PCR. KEY FINDINGS: ET-1 caused a marked and rapid in onset (1 hr) increase in ß(2)-adrenoceptor mRNA, an effect additive to that of short time (1 hr) exposure to the ß(2)-adrenoceptor agonist olodaterol. The stimulatory effect of ET-1 on ß(2)-adrenoceptor mRNA was prevented by the non-selective ET-A/ET-B receptor antagonist bosentan, indicating that it was mediated via specific ET receptors. In the presence of actinomycin D the effect of ET-1 was prevented indicating that ET-1 acts via increased transcription of the ß(2)-adrenoceptor gene. ET-1-induced up-regulation of ß(2)-adrenoceptor mRNA was also seen in the presence of cycloheximide excluding indirect effects via up-regulation of other regulatory proteins. CONCLUSIONS: ET-1 can up-regulate ß-adrenoceptor gene transcription in human lung fibroblasts.