30 research outputs found
Quantitative assessment of interstitial lung disease in Sjögren’s syndrome
Interstitial lung disease (ILD) is a frequent manifestation of Sjögren's syndrome (SS), an autoimmune disease of salivary and lacrimal glands, and affects approximately 20% of patients. No clinical or serological features appear to be useful to predict its presence, severity or progression, and chest high-resolution computed tomography (CT) remains the gold standard for diagnosis. Semiquantitative CT (SQCT) based on visual assessment (Goh and Taouli scoring) can estimate ILD extent, although it is burdened by relevant intra- and interobserver variability. Quantitative chest CT (QCT) is a promising alternative modality to assess ILD severity
Anaerobic methane oxidation coupled to manganese reduction by members of the Methanoperedenaceae
The diploid nature of the Chilean Epipetrum and a new base number in the Dioscoreaceae
13 páginas.Chromosomal analyses were conducted for the first time in all three species of the Chilean endemic Epipetrum Phil. (Dioscoreaceae; the yam family). Mitotic chromosome counts showed that all studied individuals of the rare Epipetrum bilobum and E. polyanthes, and most studied individuals of the more widespread E. humile, had 2n = 14 chromosomes. However, two populations of E. humile had 2n = 28 chromosomes. The ideograms shared a similar karyotype constitution for the three species but with a duplicated chromosome number in some populations of E. humile. Our results suggest that the Epipetrum taxa are mainly diploids, with a base number of x = 7, and the tetraploid cytotypes have arisen only in few cases. After that of Borderea (x = 6), this chromosome base number is the second lowest one found in the Dioscoreaceae. Epipetrum and Borderea are two small, relict, satellite genera of the Dioscoreaceae, endemic to Chile (South America) and the Pyrenees (Southwestern Europe), respectively. The two taxa share several morphological attributes and are adapted to rocky and mountain habitats. However, whereas Borderea is an allotetra-ploid genus of relatively recent hybrid origin, Epipetrum is diploid in common with the species found in the early branching clades of Dioscorea.Peer reviewe
A methanotrophic archaeon couples anaerobic oxidation of methane to Fe(III) reduction
Microbially mediated anaerobic oxidation of methane (AOM) is a key process in the regulation of methane emissions to the atmosphere. Iron can serve as an electron acceptor for AOM, and it has been suggested that Fe(III)-dependent AOM potentially comprises a major global methane sink. Although it has been proposed that anaerobic methanotrophic (ANME) archaea can facilitate this process, their active metabolic pathways have not been confirmed. Here we report the enrichment and characterisation of a novel archaeon in a laboratory-scale bioreactor fed with Fe(III) oxide (ferrihydrite) and methane. Long-term performance data, in conjunction with the C- and Fe-labelling batch experiments, demonstrated that AOM was coupled to Fe(III) reduction to Fe(II) in this bioreactor. Metagenomic analysis showed that this archaeon belongs to a novel genus within family Candidatus Methanoperedenaceae, and possesses genes encoding the "reverse methanogenesis" pathway, as well as multi-heme c-type cytochromes which are hypothesised to facilitate dissimilatory Fe(III) reduction. Metatranscriptomic analysis revealed upregulation of these genes, supporting that this archaeon can independently mediate AOM using Fe(III) as the terminal electron acceptor. We propose the name Candidatus "Methanoperedens ferrireducens" for this microorganism. The potential role of "M. ferrireducens" in linking the carbon and iron cycles in environments rich in methane and iron should be investigated in future research