Lessons from a Large Scale Demonstrator of the Smart and Sustainable City

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Diversity and Enzymatic Profiling of Halotolerant Micromycetes from Sebkha El Melah, a Saharan Salt Flat in Southern Tunisia

Twenty-one moderately halotolerant fungi have been isolated from sample ashes collected from Sebkha El Melah, a Saharan salt flat located in southern Tunisia. Based on morphology and sequence inference from the internal transcribed spacer regions, 28S rRNA gene and other specific genes such as β-tubulin, actin, calmodulin, and glyceraldehyde-3-phosphate dehydrogenase, the isolates were found to be distributed over 15 taxa belonging to 6 genera of Ascomycetes: Cladosporium (n=3), Alternaria (n=4), Aspergillus (n=3), Penicillium (n=5), Ulocladium (n=2), and Engyodontium (n=2). Their tolerance to different concentrations of salt in solid and liquid media was examined. Excepting Cladosporium cladosporioides JA18, all isolates were considered as alkali-halotolerant since they were able to grow in media containing 10% of salt with an initial pH 10. All isolates were resistant to oxidative stresses and low temperature whereas 5 strains belonging to Alternaria, Ulocladium, and Aspergillus genera were able to grow at 45°C. The screening of fungal strains for sets of enzyme production, namely, cellulase (CMCase), amylase, protease, lipase, and laccase, in presence of 10% NaCl, showed a variety of extracellular hydrolytic and oxidative profiles. Protease was the most abundant enzyme produced whereas laccase producers were members of the genus Cladosporium

Cultivating the uncultured: growing the recalcitrant cluster-2 Frankia strains

The repeated failures reported in cultivating some microbial lineages are a major challenge in microbial ecology and probably linked, in the case of Frankia microsymbionts to atypical patterns of auxotrophy. Comparative genomics of the so far uncultured cluster-2 Candidatus Frankia datiscae Dg1, with cultivated Frankiae has revealed genome reduction, but no obvious physiological impairments. A direct physiological assay on nodule tissues from Coriaria myrtifolia infected with a closely-related strain permitted the identification of a requirement for alkaline conditions. A high pH growth medium permitted the recovery of a slow-growing actinobacterium. The strain obtained, called BMG5.1, has short hyphae, produced diazovesicles in nitrogen-free media, and fulfilled Koch's postulates by inducing effective nodules on axenically grown Coriaria spp. and Datisca glomerata. Analysis of the draft genome confirmed its close proximity to the Candidatus Frankia datiscae Dg1 genome with the absence of 38 genes (trehalose synthase, fumarylacetoacetase, etc) in BMG5.1 and the presence of 77 other genes (CRISPR, lanthionine synthase, glutathione synthetase, catalase, Na+/H+ antiporter, etc) not found in Dg1. A multi-gene phylogeny placed the two cluster-2 strains together at the root of the Frankia radiation

Epidemiology of heart failure and long-term follow-up outcomes in a north-African population: Results from the NAtional TUnisian REgistry of Heart Failure (NATURE-HF)

International audienceThe NATURE-HF registry was aimed to describe clinical epidemiology and 1-year outcomes of outpatients and inpatients with heart failure (HF). This is a prospective, multicenter, observational survey conducted in Tunisian Cardiology centers. A total of 2040 patients were included in the study. Of these, 1632 (80%) were outpatients with chronic HF (CHF). The mean hospital stay was 8.7 ± 8.2 days. The mortality rate during the initial hospitalization event for AHF was 7.4%. The all-cause 1-year mortality rate was 22.8% among AHF patients and 10.6% among CHF patients. Among CHF patients, the older age, diabetes, anemia, reduced EF, ischemic etiology, residual congestion and the absence of ACEI/ ARBs treatment were independent predictors of 1-year cumulative rates of rehospitalization and mortality. The female sex and the functional status were independent predictors of 1-year all-cause mortality and rehospitalization in AHF patients. This study confirmed that acute HF is still associated with a poor prognosis, while the mid-term outcomes in patients with chronic HF seems to be improved. Some differences across countries may be due to different clinical characteristics and differences in healthcare systems