OIM analysis of microstructure and texture of a TRIP assisted steel after static and dynamic deformation

TRIP-assisted steel with a composition of 0.2%C, 1.6%Mn, 1.5%Al was studied in the undeformed state, after the application of 10 and 30 % static tensile strain parallel to rolling the direction of the sheet and after dynamic (Hopkinson) fracture test. Detailed examination of the microstructure and microtexture by means of electron backscattered diffraction (EBSD) was carried out in order to quantify the microstructural constituents and to study the strain distribution. The microtexture evolution and the distribution of the specific texture components between the BCC and FCC phases were studied as a function of the external strain and the strain mode-static or dynamic. The strain localization and strain distribution between the structural constituents were quantified based on local misorientation maps. The full constraint Taylor model was used to predict the texture changes in the material and the results were compared to the experimental findings. Comparing the local misorientation data it was found that at low strains the ferrite accommodates approximately 10 times more deformation than the retained austenite. The strain localizes initially on the BCC-FCC phase boundaries and is then spread in the BCC constituents (ferrite and bainite) creating a deformation skeleton in the BCC phase. It was found that the observed texture changes in the measured retained austenite texture after deformation do not correspond exactly to the model prediction. The austenite texture components which were predicted by the Taylor model were not found in the measured austenite texture after deformation which means that they are first transformed to martensite, which is considered as an indication for the selective transformation of austenite under strain

Phylogenetic and microscopic studies in the genus Lactifluus (Basidiomycota, Russulales) in West Africa, including the description of four new species

Despite the crucial ecological role of lactarioid taxa (Lactifluus, Lactarius) as common ectomycorrhiza formers in tropical African seasonal forests, their current diversity is not yet adequately assessed. During the last few years, numerous lactarioid specimens have been sampled in various ecosystems from Togo (West Africa). We generated 48 ITS sequences and aligned them against lactarioid taxa from other tropical African ecozones (Guineo-Congolean evergreen forests, Zambezian miombo). A Maximum Likelihood phylogenetic tree was inferred from a dataset of 109 sequences. The phylogenetic placement of the specimens, combined with morpho-anatomical data, supported the description of four new species from Togo within the monophyletic genus Lactifluus: within subgen. Lactifluus (L. flavellus), subgen. Russulopsis (L. longibasidius and L. pectinatus), and subgen. Edules (L. melleus). This demonstrates that the current species richness of the genus is considerably higher than hitherto estimated for African species and, in addition, a need to redefine the subgenera and sections within it

The genus Lactarius s. str. (Basidiomycota, Russulales) in Togo (West Africa) : phylogeny and a new species described

Lactarius s. str. represents a monophyletic group of about 40 species in tropical Africa, although the delimitation of the genus from Lactifluus is still in progress. Recent molecular phylogenetic and taxonomic revisions have led to numerous changes in names of tropical species formerly referred to Lactarius. To better circumscribe the genus Lactarius in Togo, we combined morphological data with sequence analyses and phylogeny inference of rDNA ITS sequences. Morphological and molecular data were generated from specimens sampled in various native woodlands and riverside forests; Lactarioid- and Russula sequences from public GenBank NCBI, and UNITE are included for phylogenetic analysis. The Maximum likelihood phylogeny tree inferred from aligned sequences supports the phylogenetic position of the studied samples from Togo within the subgenera Piperites, and Plinthogali. Lactarius s. str. includes about 13 species described from West Africa, of which eight were not previously known from Togo, including one new species: Lactarius subbaliophaeus identifiable by the presence of winged basidiospores, a pallisadic pileipellis with a uprapellis composed of cylindrical cells, inconspicuous pleurocystidia, and fusiform or tortuous, often tapering apex marginal cells. It can also be recognised by a transparent white latex that turns pinkish and then blackish, and a bluish reaction of the flesh context with FeSO4. These features mentioned do not match any of the morpho-anatomically most similar species, notably L. baliophaeus and L. griseogalus

Oxygenated machine perfusion at room temperature as an alternative for static cold storage in porcine donor hearts

Background There is a continued interest in ex situ heart perfusion as an alternative strategy for donor heart preservation. We hypothesize that oxygenated machine perfusion of donor hearts at a temperature that avoids both normothermia and deep hypothermia offers adequate and safe preservation. Methods Cardioplegia-arrested porcine donor hearts were randomly assigned to six hours of preservation using cold storage (CS, n = 5) or machine perfusion using an oxygenated acellular perfusate at 21 degrees C (MP, n = 5). Subsequently, all grafts were evaluated using the Langendorff method for 120 min. Metabolic parameters and histology were analyzed. Systolic function was assessed by contractility and elastance. Diastolic function was assessed by lusitropy and stiffness. Results For both groups, in vivo baseline and post-Langendorff biopsies were comparable, as were lactate difference and myocardial oxygen consumption. Injury markers gradually increased and were comparable. Significant weight gain was seen in MP (p = 0.008). Diastolic function was not impaired in MP, and lusitropy was superior from 30 min up to 90 min of reperfusion. Contractility was superior in MP during the first hour of evaluation. Conclusion We conclude that the initial functional outcome of MP-preserved hearts was transiently superior compared to CS, with no histological injury post-Langendorff. Our machine perfusion strategy could offer feasible and safe storage of hearts prior to transplantation. Future studies are warranted for further optimization

Oxygenated machine perfusion at room temperature as an alternative for static cold storage in porcine donor hearts

Background There is a continued interest in ex situ heart perfusion as an alternative strategy for donor heart preservation. We hypothesize that oxygenated machine perfusion of donor hearts at a temperature that avoids both normothermia and deep hypothermia offers adequate and safe preservation. Methods Cardioplegia-arrested porcine donor hearts were randomly assigned to six hours of preservation using cold storage (CS, n = 5) or machine perfusion using an oxygenated acellular perfusate at 21 degrees C (MP, n = 5). Subsequently, all grafts were evaluated using the Langendorff method for 120 min. Metabolic parameters and histology were analyzed. Systolic function was assessed by contractility and elastance. Diastolic function was assessed by lusitropy and stiffness. Results For both groups, in vivo baseline and post-Langendorff biopsies were comparable, as were lactate difference and myocardial oxygen consumption. Injury markers gradually increased and were comparable. Significant weight gain was seen in MP (p = 0.008). Diastolic function was not impaired in MP, and lusitropy was superior from 30 min up to 90 min of reperfusion. Contractility was superior in MP during the first hour of evaluation. Conclusion We conclude that the initial functional outcome of MP-preserved hearts was transiently superior compared to CS, with no histological injury post-Langendorff. Our machine perfusion strategy could offer feasible and safe storage of hearts prior to transplantation. Future studies are warranted for further optimization.</p

The pleural mesothelium and TGF-β1 pathways in restrictive allograft syndrome : a pre-clinical investigation

BACKGROUND: Chronic lung allograft dysfunction (CLAD) hampers long-term survival after lung transplantation. Common fibrosis-related mechanisms in idiopathic pulmonary fibrosis and CLAD instigated the consideration of investigating the differential regulation of pleural mesothelium and transforming growth factor-beta(1) (TGF-beta(1)) in restrictive allograft syndrome (RAS). METHODS: TGF-beta(1) was assessed in bronchoalveolar lavage (BAL) fluid using enzyme-linked immunoassay and via immune staining of explant biopsies. To assess the role of the pleura, explanted bronchiolitis obliterans syndrome (BOS) and RAS lungs were compared using computed tomography scans, calretinin stainings, Western blot, and quantititative real-time PCR. Last, a pleural mesothelial cell line was used to assess mesothelial-to-mesenchymal transition and its inhibition. RESULTS: TGF-beta(1) was increased in BAL of RAS patients (p = 0.035), and was present in the (sub) pleural area of biopsies. Explanted RAS lungs demonstrated an increased volume fraction of pleura (p = 0.0004), a higher proportion of calretinin-positive stainings (p = 0.0032), and decreased E-cadherin (p = 0.019) and increased alpha-smooth muscle actin (p = 0.0089) mRNA expression and protein levels in isolated pleural tissue. Moreover, TGF-beta(1) stimulation of pleural mesothelial cells led to a phenotypical switch to mesenchymal cells, accompanied with an increased migratory capacity. Interleukin-1 alpha was able to accentuate TGF-beta(1). induced mesothelial-to-mesenchymal transition. None of the tested drugs could inhibit mesothelial-to-mesenchymal transition at the used concentrations. CONCLUSIONS: Our results support an interplay between TGF-beta(1) and the pleural mesothelium in the pathophysiology of RAS. (C) 2019 International Society for Heart and Lung Transplantation. All rights reserved

The prognostic value of the hypoxia markers CA IX and GLUT 1 and the cytokines VEGF and IL 6 in head and neck squamous cell carcinoma treated by radiotherapy ± chemotherapy

BACKGROUND: Several parameters of the tumor microenvironment, such as hypoxia, inflammation and angiogenesis, play a critical role in tumor aggressiveness and treatment response. A major question remains if these markers can be used to stratify patients to certain treatment protocols. The purpose of this study was to investigate the inter-relationship and the prognostic significance of several biological and clinicopathological parameters in patients with head and neck squamous cell carcinoma (HNSCC) treated by radiotherapy ± chemotherapy. METHODS: We used two subgroups of a retrospective series for which CT-determined tumoral perfusion correlated with local control. In the first subgroup (n = 67), immunohistochemistry for carbonic anhydrase IX (CA IX) and glucose transporter-1 (GLUT-1) was performed on the pretreatment tumor biopsy. In the second subgroup (n = 34), enzyme linked immunosorbent assay (ELISA) was used to determine pretreatment levels of the cytokines vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) in serum. Correlation was investigated between tumoral perfusion and each of these biological markers, as well as between the markers mutually. The prognostic value of these microenvironmental parameters was also evaluated. RESULTS: For CA IX and GLUT-1, the combined assessment of patients with both markers expressed above the median showed an independent correlation with local control (p = 0.02) and disease-free survival (p = 0.04) with a trend for regional control (p = 0.06). In the second subgroup, IL-6 pretreatment serum level above the median was the only independent predictor of local control (p = 0.009), disease-free survival (p = 0.02) and overall survival (p = 0.005). CONCLUSION: To our knowledge, we are the first to report a link in HNSCC between IL-6 pretreatment serum levels and radioresistance in vivo. This link is supported by the strong prognostic association of pretreatment IL-6 with local control, known to be the most important parameter to judge radiotherapy responses. Furthermore, the combined assessment of CA IX and GLUT-1 correlated independently with prognosis. This is a valuable indication that a combined approach is important in the investigation of prognostic markers