145,891 research outputs found
Effects of propidium monoazide (PMA) treatment on mycobiome and bacteriome analysis of cystic fibrosis airways during exacerbation
Introduction and Purpose : Propidium monoazide (PMA)-pretreatment has increasingly been applied to remove the bias from dead or damaged cell artefacts, which could impact the microbiota analysis by high-throughput sequencing. Our study aimed to determine whether a PMA-pretreatment coupled with high-throughput sequencing analysis provides a different picture of the airway mycobiome and bacteriome.
Results and Discussion : We compared deep-sequencing data of mycobiota and microbiota of 15 sputum samples from 5 cystic fibrosis (CF) patients with and without prior PMA-treatment of the DNA-extracts. PMA-pretreatment had no significant effect on the entire and abundant bacterial community (genera expressed as operational taxonomic units (OTUs) with a relative abundance greater than or equal to 1%), but caused a significant difference in the intermediate community (less than 1%) when analyzing the alpha biodiversity Simpson index (p = 0.03). Regarding PMA impact on the airway mycobiota evaluated for the first time here; no significant differences in alpha diversity indexes between PMA-treated and untreated samples were observed. Regarding beta diversity analysis, the intermediate communities also differed more dramatically than the total and abundant ones when studying both mycobiome and bacteriome. Our results showed that only the intermediate (or low abundance) population diversity is impacted by PMA-treatment, and therefore that abundant taxa are mostly viable during acute exacerbation in CF. Given such a cumbersome protocol (PMA-pretreatment coupled with high-throughput sequencing), we discuss its potential interest within the follow-up of CF patients. Further studies using PMA-pretreatment are warranted to improve our "omic" knowledge of the CF airways
Large perpendicular magnetic anisotropy in magnetostrictive FeGa thin films
In this work we report the appearence of a large perpendicular magnetic
anisotropy (PMA) in FeGa thin films grown onto ZnSe/GaAs(100). This
arising anisotropy is related to the tetragonal metastable phase in as-grown
samples recently reported [M. Eddrief {\it et al.}, Phys. Rev. B {\bf 84},
161410 (2011)]. By means of ferromagnetic resonance studies we measured PMA
values up to 510 J/m. PMA vanishes when the cubic
structure is recovered upon annealing at 300C. Despite the important
values of the magnetoelastic constants measured via the cantilever method, the
consequent magnetoelastic contribution to PMA is not enough to explain the
observed anisotropy values in the distorted state. {\it Ab initio} calculations
show that the chemical ordering plays a crucial role in the appearance of PMA.
Through a phenomenological model we are able to explain that an excess of next
nearest neighbour Ga pairs (B-like ordering) along the perpendicular
direction arises as the source of PMA in FeGa thin films.Comment: 6 pages, 4 figure
Perceived motor ability and selection, optimization, and compensation: Effects of age and institutionalization
The authors examined the mediation effect of the perceived motor ability (PMA) on the
direct “effects” of age (third vs. fourth age) and residential status (institutionalized vs.
communitarians) on selection, optimization, and compensation (SOC) strategies. With a
non-probabilistic sample of 107 elders (Mdn = 80 years) from urban areas, and
controlled for cognitive impairment and depression, the authors analysed the structural
component of the path model with latent constructs that represents those relationships.
This was made only after the structural validity of the constructs had been assured.
Constructs were operationalized through the PMA questionnaire and a 16-item version
of the SOC questionnaire. Only age had direct effects on the constructs: lower PMA and
lower SOC of the elders in the fourth age. Authors also verified that the PMA mediation
effect was partial
Large perpendicular magnetic anisotropy in epitaxial Fe/MgAl2O4(001) heterostructures
We investigated perpendicular magnetic anisotropy (PMA) and related
properties of epitaxial Fe (0.7 nm)/MgAl2O4(001) heterostructures prepared by
electron-beam evaporation. Using an optimized structure, we obtained a large
PMA energy ~1 MJ/m3 at room temperature, comparable to that in
ultrathin-Fe/MgO(001) heterostructures. Both the PMA energy and saturation
magnetization show weak temperature dependence, ensuring wide working
temperature in application. The effective magnetic damping constant of the 0.7
nm Fe layer was ~0.02 using time-resolved magneto-optical Kerr effect. This
study demonstrates capability of the Fe/MgAl2O4 heterostructure for
perpendicular magnetic tunnel junctions, as well as a good agreement with
theoretical predictions.Comment: E-mail: XIANG. [email protected]
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Dedication of Robert Lee Moore Hall
Robert Lee Moore Hall, located in the northeast section of the campus, at the southeast corner of the intersection of 26th Street and Speedway, is named for Professor Emeritus Robert Lee Moore, distinguished University of Texas mathematician. The building, which was first occupied in the Fall Semester of 1972-1973, is constructed of warm tan brick and contains classrooms, laboratories, and general offices for the Departments of Astronomy, Mathematics, and Physics.Friday, October 5th, 1973, 5:40pm. Dedication Program -- Presiding: President Stephen H. Spurr -- Welcome and Recognitions: President Spurr -- Introduction of the Guest Speakers: Dr. Leonard Gillman -- Addresses: Dr. Raymond L. Wilder, Mrs. Gordon T. Whyburn, Dr. R.H. Bing, and Dr. Ralph Krause -- Dedication of Robert Lee Moore Hall: The Honorable Frank C. Erwin, Jr. -- Response: Dr. Robert Lee Moore.AstronomyMathematicsPhysicsUT Librarie
Cell migration on material-driven fibronectin microenvironments
Cell migration is a fundamental process involved in a wide range of biological phenomena. However, how the underlying mechanisms that control migration are orchestrated is not fully understood. In this work, we explore the migratory characteristics of human fibroblasts using different organisations of fibronectin (FN) triggered by two chemically similar surfaces, poly(ethyl acrylate) (PEA) and poly(methyl acrylate) (PMA); cell migration is mediated via an intermediate layer of fibronectin (FN). FN is organised into nanonetworks upon simple adsorption on PEA whereas a globular conformation is observed on PMA. We studied cell speed over the course of 24 h and the morphology of focal adhesions in terms of area and length. Additionally, we analysed the amount of cell-secreted FN as well as FN remodelling. Velocity of human fibroblasts was found to exhibit a biphasic behaviour on PEA, whereas it remained fairly constant on PMA. FA analysis revealed more mature focal adhesions on PEA over time contrary to smaller FAs found on PMA. Finally, human fibroblasts seemed to remodel adsorbed FN more on PMA than on PEA. Overall, these results indicate that the cell–protein–material interface affects cell migratory behaviour. Analysis of FAs together with FN secretion and remodelling were associated with differences in cell velocity providing insights into the factors that can modulate cell motility
The identification of markers of macrophage differentiation in PMA-stimulated THP-1 Cells and monocyte-derived macrophages
Differentiated macrophages are the resident tissue phagocytes and sentinel cells of the innate immune response. The phenotype of mature tissue macrophages represents the composite of environmental and differentiation-dependent imprinting. Phorbol-12-myristate-13-acetate (PMA) and 1,25-dihydroxyvitamin D3 (VD3) are stimuli commonly used to induce macrophage differentiation in monocytic cell lines but the extent of differentiation in comparison to primary tissue macrophages is unclear. We have compared the phenotype of the promonocytic THP-1 cell line after various protocols of differentiation utilising VD3 and PMA in comparison to primary human monocytes or monocyte-derived macrophages (MDM). Both stimuli induced changes in cell morphology indicative of differentiation but neither showed differentiation comparable to MDM. In contrast, PMA treatment followed by 5 days resting in culture without PMA (PMAr) increased cytoplasmic to nuclear ratio, increased mitochondrial and lysosomal numbers and altered differentiation-dependent cell surface markers in a pattern similar to MDM. Moreover, PMAr cells showed relative resistance to apoptotic stimuli and maintained levels of the differentiation-dependent anti-apoptotic protein Mcl-1 similar to MDM. PMAr cells retained a high phagocytic capacity for latex beads, and expressed a cytokine profile that resembled MDM in response to TLR ligands, in particular with marked TLR2 responses. Moreover, both MDM and PMAr retained marked plasticity to stimulus-directed polarization. These findings suggest a modified PMA differentiation protocol can enhance macrophage differentiation of THP-1 cells and identify increased numbers of mitochondria and lysosomes, resistance to apoptosis and the potency of TLR2 responses as important discriminators of the level of macrophage differentiation for transformed cells
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