Mazaedium evolution in the Ascomycota (Fungi) and the classification of mazaediate groups of formerly unclear relationship

Calicioid or mazaediate fungi constitute a heterogeneous assemblage of fungi sharing the presence of a mazaedium. These fungi were once treated as an order (Caliciales) of the Ascomycota but many are now known to be nested within the Arthoniomycetes, Eurotiomycetes, Lecanoromycetes and Leotiomycetes. In this study we employ multigene phylogenetic analyses of main mazaediate groups (based on nuclear 18S, 28S, 5.8S rDNA, mitochondrial 16S, and the protein coding RPB1 and Mcm7) of 116 taxa corresponding to most major groups of the inoperculate ascomycetes (“Leotiomyceta”) and a selection of Pezizomycetes, to trace the evolution of the mazaedium in the Pezizomycotina (the “Euascomycetes”). In particular, we studied the placement of three calicioid groups of uncertain position, Calycidiaceae, Coniocybaceae and Microcaliciaceae. Here, we show that the Calycidiaceae is closely related to the Sphaerophoraceae in the Lecanoromycetidae (Lecanoromycetes), as supported by overall morphology and the production of sphaerophorin. The Coniocybaceae constitute an early divergent line in the inoperculate ascomycetes and here we propose to recognize this group formally as the new class and order Coniocybomycetes, Coniocybales. The Microcaliciaceae is nested within the Ostropomycetidae (Lecanoromycetes). Both Coniocybaceae and Microcaliciaceae, although highly distinctive, lack morphological similarities to related main fungal groups. Ancestral state reconstruction suggests that the ancestor of all inoperculate ascomycetes and the ancestor of all main inoperculate ascomycete groups, with the exception of the Coniocybomycetes, was non‐mazediate, and thus confirms the large amount of parallel evolution and independent gains of the mazaedium in the history of the Ascomycota.     

A Fourier Transform-Raman Spectroscopic Study of Lichen Strategies on Granite Monuments

The biodeterioration of granite by Lecidea fuscoatra (L.) Ach., Porpidia cinereoatra (Ach.) Hertel & Knoph, and P. macrocarpa (DC.) Hertel & Schwab growing in the same environmental conditions has been studied by using Fourier transform-Raman spectroscopy. Results were significantly different for the three species, with P. cinereoatra being the most active biodeteriorative lichen. This lichen was also the only one in which calcium oxalate and gypsum were identified spectroscopically. Physical disturbances to the substratum were evidenced in all lichens studied by the incoporation of material, such as quartz and feldspar, into their thalli, but this phenomenon varied considerably from species to species. The results indicate that lichen species can adopt different strategies and can have different biodeteriorative effects on granite, independently of environmental conditions and substrate.     

White rot Basidiomycetes isolated from Chiloé National Park in Los Lagos region, Chile

Wood decomposition is an important component in forest ecosystems but information about the diversity of fungi causing decay is lacking. This is especially true for the temperate rain forests in Chile. These investigations show results of a biodiversity study of white-rot fungi in wood obtained from Chiloé National Park in Los Lagos region, Chile. Culturing from white-rotted wood followed by sequencing of the complete internal transcribed spacer region of the ribosomal DNA (rDNA) or partial large subunit region of the rDNA, identified 12 different species in the Basidiomycota. All of these fungi were characterized as white rot fungi and were identified with a BLAST match of 97 % or greater to sequences in the GenBank database. Fungi obtained were species of Phlebia, Mycoacia, Hyphodontia, Bjerkandera, Phanerochaete, Stereum, Trametes, and Ceriporiopsis. This report identifies for the first time in Chile the species Ceriporiopsis subvermispora, Hyphodontia radula, Phlebia radiata, Phanerochaete affinis, Peniophora cinerea, Stereum gausapatum, Phlebia setulosa and Phanerochaete sordida. Scanning electron microscopy was used to characterize the type of decay caused by the fungi that were isolated and a combination of selective lignin degraders and simultaneous white rot fungi were found. Fungi that cause a selective degradation of lignin are of interest for bioprocessing technologies that require modification or degradation of lignin without cellulose removal.     

Interaction of a peptide corresponding to the loop domain of the S2 SARS-CoV virus protein with model membranes

The severe acute respiratory syndrome coronavirus (SARS-CoV) envelope spike (S) glycoprotein is responsible for the fusion between the membranes of the virus and the target cell. In the case of the S2 domain of protein S, it has been found a highly hydrophobic and interfacial domain flanked by the heptad repeat 1 and 2 regions; significantly, different peptides pertaining to this domain have shown a significant leakage effect and an important plaque formation inhibition, which, similarly to HIV-1 gp41, support the role of this region in the fusion process. Therefore, we have carried out a study of the binding and interaction with model membranes of a peptide corresponding to segment 1073–1095 of the SARS-CoV S glycoprotein, peptide SARS_L in the presence of different membrane model systems, as well as the structural changes taking place in both the lipid and the peptide induced by the binding of the peptide to the membrane. Our results show that SARS_L strongly partitions into phospholipid membranes and organizes differently in lipid environments, displaying membrane activity modulated by the lipid composition of the membrane. These data would support its role in SARS-CoV mediated membrane fusion and suggest that the region where this peptide resides could be involved in the merging of the viral and target cell membranes.     

Trypsin inhibitors in xoconostle seeds (Opuntia joconostle Weber.)

Seed proteins recovered after heating a seed extract from Opuntia joconostle Weber (xoconostle, an acid cactus pear) were screened for different biochemical activities, detecting only trypsin-like inhibitory activity. Two trypsin-like inhibitor forms from seeds were separated by RP-HPLC and partially sequenced and characterized as an enriched mixture. They were evaluated for inhibition on several serine proteinases, but only trypsin-like inhibition was detected by the inhibitor extract. The two isolated forms, OjTI 1 and OjTI 2 showed low molecular weights of 4.26 and 4.17 kDa as determined by mass spectrometry. An enriched inhibitory fraction showed a high thermal stability by retaining the activity after heating the sample for 1 h at 90 °C, as well as after heating for at 120 °C under 1 kg/cm² for 15 min at different pH values. Partial sequence of the two forms was determined by mass spectrometry indicating that they were similar and after alignments analysis they showed the highest similarity with the trypsin inhibitor from O. streptacantha and to a lesser extent to other trypsin inhibitors of the MEROPS database families. The inhibitory spectrum was evaluated against several digestive enzymes from pests and beneficial insects from several taxonomic orders.     

Why and how to objectively evaluate medical gestures?

Junior physicians mainly learn during their observation in the operative room. The senior physicians evaluate them based on the same kind of observation. Knowledge transfer evaluation is thus done without quantitative methods and it mainly lies on a subjective assessment. In this paper, we present some recent techniques used to objectively evaluate medical gestures. The classical techniques used are Hidden Markov Models (HMM) or Dynamic Time Warping (DTW). Both techniques lies on the temporal analysis of the gestures. We proposed here a technique based on the arc length parametrization in order to analyze the gestures in space which is more appropriate because it gives information about the shape of the gestures independently of the chosen coordinate system.     

From the root to the stem: interaction between the biocontrol root endophyte Pseudomonas fluorescens PICF7 and the pathogen Pseudomonas savastanoi NCPPB 3335 in olive knots

Olive knot disease, caused by Pseudomonas savastanoi pv. savastanoi, is one of the most important biotic constraints for olive cultivation. Pseudomonas fluorescens PICF7, a natural colonizer of olive roots and effective biological control agent (BCA) against Verticillium wilt of olive, was examined as potential BCA against olive knot disease. Bioassays using in vitro-propagated olive plants were carried out to assess whether strain PICF7 controlled knot development either when co-inoculated with the pathogen in stems or when the BCA (in roots) and the pathogen (in stems) were spatially separated. Results showed that PICF7 was able to establish and persist in stem tissues upon artificial inoculation. While PICF7 was not able to suppress disease development, its presence transiently decreased pathogen population size, produced less necrotic tumours, and sharply altered the localization of the pathogen in the hyperplasic tissue, which may pose epidemiological consequences. Confocal laser scanning microscopy combined with fluorescent tagging of bacteria revealed that when PICF7 was absent the pathogen tended to be localized at the knot surface. However, presence of the BCA seemed to confine P. savastanoi at inner regions of the tumours. This approach has also enabled to prove that the pathogen can moved systemically beyond the hypertrophied tissue.     

The Phosphate Source Influences Gene Expression and Quality of Mineralization during In Vitro Osteogenic Differentiation of Human Mesenchymal Stem Cells

For in vitro differentiation of bone marrow-derived mesenchymal stem cells/mesenchymal stromal cells into osteoblasts by 2-dimensional cell culture a variety of protocols have been used and evaluated in the past. Especially the external phosphate source used to induce mineralization varies considerably both in respect to chemical composition and concentration. In light of the recent findings that inorganic phosphate directs gene expression of genes crucial for bone development, the need for a standardized phosphate source in in vitro differentiation becomes apparent. We show that chemical composition (inorganic versus organic phosphate origin) and concentration of phosphate supplementation exert a severe impact on the results of gene expression for the genes commonly used as markers for osteoblast formation as well as on the composition of the mineral formed. Specifically, the intensity of gene expression does not necessarily correlate with a high quality mineralized matrix. Our study demonstrates advantages of using inorganic phosphate instead of β-glycerophosphate and propose colorimetric quantification methods for calcium and phosphate ions as cost- and time-effective alternatives to X-ray diffraction and Fourier-transform infrared spectroscopy for determination of the calcium phosphate ratio and concentration of mineral matrix formed under in vitro-conditions. We critically discuss the different assays used to assess in vitro bone formation in respect to specificity and provide a detailed in vitro protocol that could help to avoid contradictory results due to variances in experimental design.     

Type 2 Endoleaks: The Diagnostic Performance of Non-Specialized Readers on Arterial and Venous Phase Multi-Slice CT Angiography

PurposeTo define the diagnostic precision of non-specialized readers in the detection of type 2 endoleaks (T2EL) in arterial versus venous phase acquisitions, and to evaluate an approach for radiation dose reduction.MethodsThe pre-discharge and final follow-up multi-slice CT angiographies of 167 patients were retrospectively analyzed. Image data were separated into an arterial and a venous phase reading set. Two radiology residents assessed the reading sets for the presence of a T2EL, feeding vessels, and aneurysm sac size. Findings were compared with a standard of reference established by two experts in interventional radiology. The effective dose was calculated.ResultsOverall, experts detected 131 T2ELs, and 331 feeding vessels in 334 examinations. Persistent T2ELs causing aneurysm sac growth > 5 mm were detected in 20 patients. Radiation in arterial and venous phases contributed to a mean of 58.6% and 39.0% of the total effective dose. Findings of reader 1 and 2 showed comparable sensitivities in arterial sets of 80.9 versus 85.5 (p = 0.09), and in venous sets of 73.3 versus 79.4 (p = 0.15), respectively. Reader 1 and 2 achieved a significant higher detection rate of feeding vessels with arterial compared to venous set (p = 0.04, p < 0.01). Both readers correctly identified T2ELs with growing aneurysm sac in all cases, independent of the acquisition phase.ConclusionArterial acquisitions enable non-specialized readers an accurate detection of T2ELs, and a significant better identification of feeding vessels. Based on our results, it seems reasonable to eliminate venous phase acquisitions.