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To evaluate the performance of a two‐step strategy compared with the International Ovarian Tumor Analysis (IOTA) ‐ Assessment of Different NEoplasias in the adneXa (ADNEX) model for preoperative classification of adnexal masses. An ambispective diagnostic accuracy study based on ultrasound data collected at one university hospital between 2012 and 2018. Two ultrasonographers classified the adnexal masses using IOTA Simple Rules (first step). Not classifiable masses were evaluated using the IOTA ADNEX model (second step). Also, all masses were classified using the IOTA ADNEX model. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), positive likelihood ratio (LR+) and negative likelihood ratio (LR−), and receiver operating characteristic (ROC) curve were estimated. A Pvalue of <.05 was used to determine statistical significance. The study included 548 patients and 606 masses. Patients' median age was 41 years with an interquartile range between 32 and 51 years. In the first step, 89 (14%) masses were not classifiable. In the second step, 55 (61.8%) masses were classified as malignant. Furthermore, for the totality of 606 masses, the IOTA ADNEX model estimated the probability that 126 (20.8%) masses were malignant. The two‐step strategy had a sensitivity, specificity, PPV, NPV, LR+, LR−, and ROC curve of 86.8%, 91.01%, 51.9%, 98.4%, 9.7, 0.1, and 0.889, respectively; compared to IOTA ADNEX model that had values of 91.8%, 87.16%, 44.4%, 99%, 7.1, 0.09, and 0.895, respectively. The two‐step strategy shows a similar diagnostic performance when compared to the IOTA ADNEX model. The IOTA ADNEX model involves only one step and can be more practical, and thus would be recommended to use. Access the CME test hereand search by article title.

Remarkably well-preserved soft tissues in Mesozoic fossils have yielded substantial insights into the evolution of feathers1. New evidence of branched feathers in pterosaurs suggests that feathers originated in the avemetatarsalian ancestor of pterosaurs and dinosaurs in the Early Triassic2, but the homology of these pterosaur structures with feathers is controversial3,4. Reports of pterosaur feathers with homogeneous ovoid melanosome geometries2,5suggest that they exhibited limited variation in colour, supporting hypotheses that early feathers functioned primarily in thermoregulation6. Here we report the presence of diverse melanosome geometries in the skin and simple and branched feathers of a tapejarid pterosaur from the Early Cretaceous found in Brazil. The melanosomes form distinct populations in different feather types and the skin, a feature previously known only in theropod dinosaurs, including birds. These tissue-specific melanosome geometries in pterosaurs indicate that manipulation of feather colour—and thus functions of feathers in visual communication—has deep evolutionary origins. These features show that genetic regulation of melanosome chemistry and shape7–9was active early in feather evolution.

Evolutionary biologists have long been interested in understanding the factors that promote diversification in organisms, often focussing on distinct and/or conspicuous phenotypes with direct effects on natural or sexual selection such as body size and plumage coloration. However, multiple traits that potentially influence net diversification are not conspicuous and/or might be concealed. One such trait, the dark, melanin-rich skin concealed beneath the feathers, evolved more than 100 times during avian evolution, frequently in association with white feathers on the crown and UV-rich environments, suggesting that it is a UV-photoprotective adaptation. Furthermore, multiple species are polymorphic, having both light and dark skin potentially aiding occupation in different UV radiation environments. As such these polymorphisms are predicted to occur in species with large latitudinal variation in their distribution. Furthermore, by alleviating evolutionary constraints on feather colour, the evolution of dark skin may promote net diversification. Here, using an expanded dataset on bird skin coloration of 3033 species we found that more than 19% of species had dark skin. In contrast to our prediction, dark skinned birds have smaller distribution ranges. Furthermore, both dark skin and polymorphism in skin coloration promote net diversification. These results suggest that even concealed traits can influence large scale evolutionary events such as diversification in birds.

Colour is often not a static trait but can change over time either through biotic or abiotic factors. Humidity-dependent colour change can occur through either morphological change (e.g. to feather barbules in birds) or by the replacement of air by water causing a shift in refractive index, as seen in arthropod multi-layer cuticles or scales. The scaled springtail Lepidocyrtus cyaneushas scales that produce colour largely via thin film interference from their lamina. We observed a marked colour change from golden to violet/purple coloration in humid conditions. Light microscopy, micro-spectrophotometry, contact angle goniometry and optical modelling indicate that the formation of a thin film of water on top of the hydrophilic scales increases their laminar thin film thickness, causing a shift towards violet/purple colour. Evaporation of the water film causes the metallic golden colour to return. This constitutes a remarkably rapid colour change (in the order of seconds), only limited by the speed of water film condensation and evaporation, that may serve as inspiration for new dynamically coloured materials and sensors.

Until recently, and when compared with diurnal birds that use contrasting plumage patches and complex feather structures to convey visual information, communication in nocturnal and crepuscular species was considered to follow acoustic and chemical channels. However, many birds that are active in low-light environments have evolved intensely white plumage patches within otherwise inconspicuous plumages. We used spectrophotometry, electron microscopy, and optical modelling to explain the mechanisms producing bright white tail feather tips of the Eurasian woodcock Scolopax rusticola. Their diffuse reflectance was approximately 30% higher than any previously measured feather. This intense reflectance is the result of incoherent light scattering from a disordered nanostructure composed of keratin and air within the barb rami. In addition, the flattening, thickening and arrangement of those barbs create a Venetian-blind-like macrostructure that enhances the surface area for light reflection. We suggest that the woodcocks have evolved these bright white feather patches for long-range visual communication in dimly lit environments.

The aim of the current study was to search for the presence of genetic variants in the CYP21A2 Zpromoter regulatory region in patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency. Screening of the 10 most frequent pseudogene-derived mutations was followed by direct sequencing of the entire coding sequence, the proximal promoter, and a distal regulatory region in DNA samples from patients with at least one non-determined allele. We report three non-classical patients that presented a novel genetic variant—g.15626A>G—within the Z promoter regulatory region. In all the patients, the novel variant was found in ciswith the mild, less frequent, p.P482S mutation located in the exon 10 of the CYP21A2gene. The putative pathogenic implication of the novel variant was assessed by in silico analyses and in vitro assays. Topological analyses showed differences in the curvature and bendability of the DNA region bearing the novel variant. By performing functional studies, a significantly decreased activity of a reporter gene placed downstream from the regulatory region was found by the G transition. Our results may suggest that the activity of an allele bearing the p.P482S mutation may be influenced by the misregulated CYP21A2transcriptional activity exerted by the Z promoter A>G variation.

Relative to other metazoans, the mammalian integument is thought to be limited in colour. In particular, while iridescence is widespread among birds and arthropods, it has only rarely been reported in mammals. Here, we examine the colour, morphology and optical mechanisms in hairs from four species of golden mole (Mammalia: Chrysochloridae) that are characterized by sheens ranging from purple to green. Microspectrophotometry reveals that this colour is weak and variable. Iridescent hairs are flattened and have highly reduced cuticular scales, providing a broad and smooth surface for light reflection. These scales form multiple layers of light and dark materials of consistent thickness, strikingly similar to those in the elytra of iridescent beetles. Optical modelling suggests that the multi-layers produce colour through thin-film interference, and that the sensitivity of this mechanism to slight changes in layer thickness and number explains colour variability. While coloured integumentary structures are typically thought to evolve as sexual ornaments, the blindness of golden moles suggests that the colour may be an epiphenomenon resulting from evolution via other selective factors, including the ability to move and keep clean in dirt and sand.

Abstract: Avian incubation dramatically reduces the abundance and diversity of microbial assemblages on eggshells, and this effect has been hypothesized as an adaptive explanation for partial incubation, the bouts of incubation that some birds perform during the egg-laying period. However, the mechanisms for these antimicrobial effects are largely unknown. In this study, we hypothesized that microbial inhibition is partly achieved through removal of liquid water, which generally enhances microbial growth, from eggshells, and experimentally tested this hypothesis in two ways. First, we placed the first- and second-laid eggs of tree swallow (Tachycineta bicolor) clutches in unincubated holding nests with either ambient or increased water on eggshells. Second, we added water to eggshells in naturally partially incubated nests. We compared microbial growth on shells during a 5-day experimental period and found that, as predicted, both unincubated groups had higher microbial growth than naturally partially incubated controls, and that only in the absence of incubation did wetted eggs have higher microbial growth than unwetted eggs. Thus, we have shown that water increases microbial growth on eggshells and that incubation nullifies these effects, suggesting that removal of water from egg surfaces is one proximate mechanism for the antimicrobial effects of incubation.

The diverse colours of bird feathers are produced by both pigments and nanostructures, and can have substantial thermal consequences. This is because reflectance, transmittance and absorption of differently coloured tissues affect the heat loads acquired from solar radiation. Using reflectance measurements and heating experiments on sunbird museum specimens, we tested the hypothesis that colour and their colour producing mechanisms affect feather surface heating and the heat transferred to skin level. As predicted, we found that surface temperatures were strongly correlated with plumage reflectivity when exposed to a radiative heat source and, likewise, temperatures reached at skin level decreased with increasing reflectivity. Indeed, nanostructured melanin-based iridescent feathers (green, purple, blue) reflected less light and heated more than unstructured melanin-based colours (grey, brown, black), as well as olives, carotenoid-based colours (yellow, orange, red) and non-pigmented whites. We used optical and heat modelling to test if differences in nanostructuring of melanin, or the bulk melanin content itself, better explains the differences between melanin-based feathers. These models showed that the greater melanin content and, to a lesser extent, the shape of the melanosomes explain the greater photothermal absorption in iridescent feathers. Our results suggest that iridescence can increase heat loads, and potentially alter birds' thermal balance.

The mechanisms and evolution of metallic structural colours are of both fundamental and applied interest, yet most work in arthropods has focused on derived butterflies and beetles with distinct hues. In particular, basal hexapods—groups with many scaled, metallic representatives—are currently poorly studied and controversial, with some recent studies suggesting either that thin-film (lamina thickness) or diffraction grating (longitudinal ridges, cross-ribs) elements produce these colours in early Lepidoptera and one springtail (Collembola) species. Especially the collembolan basal scale design, consisting of a single lamina and longitudinal ridges with smooth valleys lacking cross-ribs, makes them an interesting group to explore the mechanisms of metallic coloration. Using microspectroscopy, Raman spectroscopy, electron microscopy and finite-difference time-domain optical modelling, we investigated scale colour in seven springtail species that show clear metallic coloration. Reflectance spectra are largely uniform and exhibit a broadband metallic/golden coloration with peaks in the violet/blue region. Our simulations confirm the role of the longitudinal ridges, working in conjunction with thin-film effects to produce a broadband metallic coloration. Broadband coloration occurs through spatial colour mixing, which probably results from nanoscale variation in scale thickness and ridge height and distance. These results provide crucial insights into the colour production mechanisms in a basal scale design and highlight the need for further investigation of scaled, basal arthropods.

Seabirds have evolved numerous adaptations that allow them to thrive under hostile conditions. Many seabirds share similar colour patterns, often with dark wings, suggesting that their coloration might be adaptive. Interestingly, these darker wings become hotter when birds fly under high solar irradiance, and previous studies on aerofoils have provided evidence that aerofoil surface heating can affect the ratio between lift and drag, i.e. flight efficiency. However, whether this effect benefits birds remains unknown. Here, we first used phylogenetic analyses to show that strictly oceanic seabirds with a higher glide performance (optimized by reduced sink rates, i.e. the altitude lost over time) have evolved darker wings, potentially as an additional adaptation to improve flight. Using wind tunnel experiments, we then showed that radiative heating of bird wings indeed improves their flight efficiency. These results illustrate that seabirds may have evolved wing pigmentation in part through selection for flight performance under extreme ocean conditions. We suggest that other bird clades, particularly long-distance migrants, might also benefit from this effect and therefore might show similar evolutionary trajectories. These findings may also serve as a guide for bioinspired innovations in aerospace and aviation, especially in low-speed regimes.

Acitretin is an aromatic retinoid analog of vitamin A. Drugs of this group are well‐known teratogenic agents. Nevertheless, acitretin embryopathy has been described only in fetuses.An infant was exposed to 10 mg/day of acitretin from the beginning of pregnancy until the 10th gestational week. At term, the newborn showed the following abnormalities: microcephaly, epicanthal folds, low nasal bridge, high palate, cup‐shaped ears, anteverted nostrils, atrial septal defect, and bilateral sensorineural deafness. At 18 months of age, the patient showed microcephaly and neurodevelopmental delay.Our patient shows a pattern of anomalies resembling that observed in isotretinoin‐ and etretinate‐exposed children. After ingestion, acitretin is partially converted into etretinate, and etretinate is partially metabolized into acitretin. A similar phenotype would therefore be expected after prenatal exposure to either drug. Moreover, in the present case, teratogenic effects were observed even though the dose was lower than in the previously reported acitretin embryopathy cases. Therefore, we propose that different retinoids, acitretin included, produce only one malformation pattern with variable phenotypic expression. Birth Defects Research (Part A), 2004. © 2004 Wiley‐Liss, Inc.

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Objective. To describe the medical genetics services in Argentina, in order to help organize a network to coordinate those services, decrease inequity in access to them, and promote the comprehensive development of medical genetics in the country. Methods. In April-August 2004 a survey was conducted of centers providing medical genetics services in Argentina, looking at their human resources, diagnostic procedures, the services that patients use, and funding. The survey covered service centers that conduct genetic assessment, cytogenetic diagnostic testing, molecular biology testing, and biochemical testing to detect birth defects or genetic disorders. Centers that were devoted exclusively to research were not surveyed. Results. A total of 134 centers fulfilled the selection criteria for the survey; 84 of them were private services, and the other 50 were publicly managed services, at universities and hospitals. The 50 public facilities had a total of 67 physicians who had studied clinical genetics, plus 133 non-medical laboratory professionals. A majority of the 50 centers performed clinical and cytogenetic diagnoses, with a smaller number performing molecular, biochemical, and prenatal diagnoses. More than 70% of the centers and human resources were located in an area that includes the city of Buenos Aires, the province of Buenos Aires, and the nearby north-central provinces of Córdoba and Santa Fe. The 50 public centers were found mainly in large cities; 10 of the country's 23 provinces had no public services. Conclusions. There is a great geographic disparity in the availability of resources as well as wide variability in the diagnostic procedures that are provided in the different service centers. The unequal distribution of the facilities is an organizational problem that will require the application of policies to guarantee minimum services for people in all regions of the country, as well as access to more complex diagnostic procedures. [ABSTRACT FROM AUTHOR]