40 research outputs found
ABDERITID MARSUPIALS FROM THE MIOCENE OF PATAGONIA: AN ASSESSMENT OF FORM, FUNCTION, AND EVOLUTION
Comparative Study of Human and Automated Screening for Antinuclear Antibodies by Immunofluorescence on HEp-2 Cells
Background: Several automated systems had been developed in order to reduce inter-observer variability in
indirect immunofluorescence (IIF) interpretation. We aimed to evaluate the performance of a processing system in
antinuclear antibodies (ANA) screening on HEp-2 cells.
Patients and Methods: This study included 64 ANA-positive sera and 107 ANA-negative sera that underwent IIF on two
commercial kits of HEp-2 cells (BioSystems® and Euroimmun®). IIF results were compared with a novel automated
interpretation system, the “CyclopusCADImmuno®” (CAD).
Results: All ANA-positive sera images were recognized as positive by CAD (sensitivity = 100%), while 17 (15.9%) of the
ANA-negative sera images were interpreted as positive (specificity = 84.1%), =0.799 (SD=0.045). Comparison of IIF
pattern determination between human and CAD system revealed on HEp-2 (BioSystems®), a complete concordance in
6 (9.37%) sera, a partial concordance (sharing of at least 1 pattern) in 42 (65.6%) cases and in 16 (25%) sera the
pattern interpretation was discordant. Similarly, on HEp-2 (Euroimmun®) the concordance in pattern interpretation was
total in 5 (7.8%) sera, partial in 39 (60.9%) and absent in 20 (31.25%). For both tested HEp-2 cells kits agreement was
enhanced for the most common patterns, homogenous, fine speckled and coarse speckled. While there was an issue in
identification of nucleolar, dots and nuclear membranous patterns by CAD.
Conclusion: Assessment of ANA by IIF on HEp-2 cells using the automated interpretation system, the
“CyclopusCADImmuno®” is a reliable method for positive/negative differentiation. Continuous integration of IIF images
would improve the pattern identification by the CAD
Preliminary results of the project A.I.D.A. (Auto Immunity: Diagnosis Assisted by computer)
In this paper, are presented the preliminary results of the A.I.D.A. (Auto Immunity: Diagnosis
Assisted by computer) project which is developed in the frame of the cross-border cooperation Italy-Tunisia.
According to the main objectives of this project, a database of interpreted Indirect ImmunoFluorescence (IIF)
images on HEp 2 cells is being collected thanks to the contribution of Italian and Tunisian experts involved in
routine diagnosis of autoimmune diseases. Through exchanging images and double reporting; a Gold Standard
database, containing around 1000 double reported IIF images with different patterns including negative tests,
has been settled. This Gold Standard database has been used for optimization of a computing solution (CADComputer
Aided Detection) and for assessment of its added value in order to be used along with an
immunologist as a second reader in detection of auto antibodies for autoimmune disease diagnosis. From the
preliminary results obtained, the CAD appeared more powerful than junior immunologists used as second
readers and may significantly improve their efficacy
Computer-Assisted Classification Patterns in Autoimmune Diagnostics: The AIDA Project
Antinuclear antibodies (ANAs) are significant biomarkers in the diagnosis of autoimmune diseases in humans, done by mean of
Indirect ImmunoFluorescence (IIF)method, and performed by analyzing patterns and fluorescence intensity. This paper introduces
the AIDA Project (autoimmunity: diagnosis assisted by computer) developed in the framework of an Italy-Tunisia cross-border
cooperation and its preliminary results. A database of interpreted IIF images is being collected through the exchange of images
and double reporting and a Gold Standard database, containing around 1000 double reported images, has been settled. The Gold
Standard database is used for optimization of aCAD(Computer AidedDetection) solution and for the assessment of its added value,
in order to be applied along with an Immunologist as a second Reader in detection of autoantibodies. This CAD system is able to
identify on IIF images the fluorescence intensity and the fluorescence pattern. Preliminary results show that CAD, used as second
Reader, appeared to perform better than Junior Immunologists and hence may significantly improve their efficacy; compared with
two Junior Immunologists, the CAD system showed higher Intensity Accuracy (85,5% versus 66,0% and 66,0%), higher Patterns
Accuracy (79,3% versus 48,0% and 66,2%), and higher Mean Class Accuracy (79,4% versus 56,7% and 64.2%)
Splendid oddness: revisiting the curious trophic relationships of South American Pleistocene mammals and their abundance
Multigene phylogeny of the Mustelidae: Resolving relationships, tempo and biogeographic history of a mammalian adaptive radiation
<p>Abstract</p> <p>Background</p> <p>Adaptive radiation, the evolution of ecological and phenotypic diversity from a common ancestor, is a central concept in evolutionary biology and characterizes the evolutionary histories of many groups of organisms. One such group is the Mustelidae, the most species-rich family within the mammalian order Carnivora, encompassing 59 species classified into 22 genera. Extant mustelids display extensive ecomorphological diversity, with different lineages having evolved into an array of adaptive zones, from fossorial badgers to semi-aquatic otters. Mustelids are also widely distributed, with multiple genera found on different continents. As with other groups that have undergone adaptive radiation, resolving the phylogenetic history of mustelids presents a number of challenges because ecomorphological convergence may potentially confound morphologically based phylogenetic inferences, and because adaptive radiations often include one or more periods of rapid cladogenesis that require a large amount of data to resolve.</p> <p>Results</p> <p>We constructed a nearly complete generic-level phylogeny of the Mustelidae using a data matrix comprising 22 gene segments (~12,000 base pairs) analyzed with maximum parsimony, maximum likelihood and Bayesian inference methods. We show that mustelids are consistently resolved with high nodal support into four major clades and three monotypic lineages. Using Bayesian dating techniques, we provide evidence that mustelids underwent two bursts of diversification that coincide with major paleoenvironmental and biotic changes that occurred during the Neogene and correspond with similar bursts of cladogenesis in other vertebrate groups. Biogeographical analyses indicate that most of the extant diversity of mustelids originated in Eurasia and mustelids have colonized Africa, North America and South America on multiple occasions.</p> <p>Conclusion</p> <p>Combined with information from the fossil record, our phylogenetic and dating analyses suggest that mustelid diversification may have been spurred by a combination of faunal turnover events and diversification at lower trophic levels, ultimately caused by climatically driven environmental changes. Our biogeographic analyses show Eurasia as the center of origin of mustelid diversity and that mustelids in Africa, North America and South America have been assembled over time largely via dispersal, which has important implications for understanding the ecology of mustelid communities.</p
Data from: Adaptive evolution of a derived radius morphology in manakins (Aves, Pipridae) to support acrobatic display behavior
The morphology of the avian skeleton is often studied in the context of adaptations for powered flight. The effects of other evolutionary forces, such as sexual selection, on avian skeletal design are unclear, even though birds produce diverse behaviors that undoubtedly require a variety of osteological modifications. Here, we investigate this issue in a family of passerine birds called manakins (Pipridae), which have evolved physically unusual and elaborate courtship displays. We report that, in species within the genus Manacus, the shaft of the radius is heavily flattened and shows substantial solidification. Past work anecdotally notes this morphology and attributes it to the species' ability to hit their wings together above their heads to produce loud mechanical sonations. Our results show that this feature is unique to Manacus compared to the other species in our study, including a variety of taxa that produce other sonations through alternate wing mechanisms. At the same time, our data reveal striking similarities across species in total radius volume and solidification. Together, this suggests that supposedly adaptive alterations in radial morphology occur within a conserved framework of a set radius volume and solidness, which in turn is likely determined by natural selection. Further allometric analyses imply that the radius is less constrained by body size and the structural demands that underlie powered flight, compared to other forelimb bones that are mostly unmodified across taxa. These results are consistent with the idea that the radius is more susceptible to selective modification by sexual selection. Overall, this study provides some of the first insight into the osteological evolution of passerine birds, as well as the way in which opposing selective forces can shape skeletal design in these species
Determination of the wingsnap sonation mechanism of the goldencollared manakin (Manacus vitellinus)
Male golden-collared manakins (Manacus vitellinus), small suboscine passeriform birds of Panamanian forests, communicate acoustically using a variety of non-vocal sonations. The most prominent sonations are single or multiple intense 'wingsnaps' with a dominant acoustic frequency around 5 kHz. Several hypotheses have been proposed addressing the source of the sound, ranging from purely aerodynamic origins (due to a rapid jet of air formed by the wings or by a 'whiplike' motion) to purely structural origins (such as physical contact of the wings), but without definitive assessment. Using anatomical analysis as well as high-speed video and synchronized audio recordings, we show that compared with related species, M. vitellinus radii are morphologically unique and confirm that they collide over the back of the bird at the moment (±1 ms) the wingsnap is produced. Using aeroacoustic theory, we quantitatively estimate the acoustic signatures from several sonation mechanisms.We conclude that only the physical contact hypothesis, wherein the wing collisions create the sound, is consistent with the measured sonation