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BACKGROUND Polycystic ovary syndrome (PCOS) is associated with insulin resistance and features in common with the metabolic syndrome (MetS)—factors shown to predict cardiovascular risk and type 2 diabetes. We investigated the prevalence and characteristics of the MetS in PCOS by three definitions—World Health Organization (WHO), National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP-III) and International Diabetes Federation (IDF)—and compared that with the background population. METHODS Cross-sectional study of 168 women with PCOS and 883 age-matched controls from the Australian Diabetes, Obesity and Lifestyle (AusDiab) study. RESULTS Prevalence of the MetS in PCOS subjects was 33% by WHO, 37% by NCEP-ATP-III and 40% by IDF criteria, compared with 10% by NCEP-ATP-III and 13% by IDF in controls (P P = 0.027) in obese women (BMI > 30 kg/m2), and higher but not significantly so in overweight (BMI 25–30 kg/m2) women (P = 0.052). Dehydroepiandrosterone sulphate was associated with a lower risk of the MetS—Odds ratio 0.86 (95% confidence interval, 0.77–0.97, P = 0.011). CONCLUSIONS An approximate 4-fold increase in the prevalence of the MetS in women with PCOS compared with the general population, consistent with the proposed major role of insulin and obesity in the syndrome, implies greater risk of cardiometabolic disease in women with PCOS. However, this estimate is likely to vary according to PCOS definition, ethnicity and different aetiological pathways to PCOS. [ABSTRACT FROM AUTHOR]

Three-dimensional reconstructions of imaging data are an increasingly common approach for studying anatomical structure. However, certain aspects of anatomy, including microscopic structure and differentiating tissue types, continue to benefit from traditional histological analyses. We present here a detailed methodology for combining data from microCT and histological imaging to create 3D virtual reconstructions for visualization and further analyses. We used this approach to study the distribution of olfactory mucosa on ethmoturbinal I of an adult pygmy slow loris, Nycticebus pygmaeus. MicroCT imaging of the specimen was followed by processing, embedding, and sectioning for histological analysis. We identified corresponding features in the CT and histological data, and used these to reconstruct the plane of section in the CT volume. The CT volume was then digitally re-sliced, such that orthogonal sections of the CT image corresponded to histological sections. Histological images were annotated for the features of interest (in this case, the contour of soft tissue on ethmoturbinal I and the extent of olfactory mucosa), and annotations were transferred to binary masks in the CT volume. These masks were combined with density-based surface reconstructions of the skull to create an enhanced 3D virtual reconstruction, in which the bony surfaces are coded for mucosal function. We identified a series of issues that may be raised in this approach, for example, deformation related to histological processing, and we make recommendations for addressing these issues. This method provides an evidence-based approach to 3D visualization and analysis of microscopic features in an anatomic context., (© 2014 Wiley Periodicals, Inc.)

Objective: To determine whether premature sagittal craniosynostosis is associated with developmental instability in the skull by analyzing fluctuating asymmetry in skull shape., Design: Cranial shape was quantified by collecting coordinate data from landmarks located on three-dimensional reconstructions of preoperative computed tomography (CT) images of 22 children with sagittal craniosynostosis and 22 age-matched controls. A fluctuating asymmetry application of Euclidean distance matrix analysis (EDMA) was used to quantify and compare asymmetry in cranial shape using these landmark data., Results: In contrast to expectations, the sagittal craniosynostosis group did not show a statistically significant increase in the overall level of fluctuating asymmetry relative to the control group. However, we discerned statistically significant localized increases in fluctuating asymmetry in the sagittal craniosynostosis group at pterion and the anterior clinoid processes (alpha = .05). We also determined a significant correlation of fluctuating asymmetry values between the two groups (r = .71)., Conclusions: We conclude that there is no evidence of a role for system-wide developmental instability in the etiology of nonsyndromic sagittal craniosynostosis. However, the localized evidence of asymmetry at the anterior clinoid processes in the sagittal synostosis group suggests an association with the tracts of dura mater that attach there.

We report the oldest known record of Lagomorpha, based on distinctive, small ankle bones (calcaneus and talus) from Early Eocene deposits (Middle Ypresian equivalent, ca 53 Myr ago) of Gujarat, west-central India. The fossils predate the oldest previously known crown lagomorphs by several million years and extend the record of lagomorphs on the Indian subcontinent by 35 Myr. The bones show a mosaic of derived cursorial adaptations found in gracile Leporidae (rabbits and hares) and primitive traits characteristic of extant Ochotonidae (pikas) and more robust leporids. Together with gracile and robust calcanei from the Middle Eocene of Shanghuang, China, also reported here, the Indian fossils suggest that diversification within crown Lagomorpha and possibly divergence of the family Leporidae were already underway in the Early Eocene.

Background: The purpose of this study was to quantitate preoperative osseous dysmorphology in a homogeneous group of 3-month-old infants with unilateral complete cleft lip and palate., Methods: High-resolution computed tomography scans of 28 infants with unilateral complete cleft lip and palate were the basis for study. Coordinate data from 43 landmarks on the skull were collected using surface-rendered reconstructions of scan data. Euclidean distance matrix analysis was used to assess the degree of asymmetry between the cleft and noncleft sides of the craniofacial skeleton., Results: Linear distances involving primary and secondary landmarks (those that are located on or within the bony cleft and those that are near the cleft in the adjacent oronasal area, respectively) were highly asymmetric, with significantly greater distances on the cleft side. In addition, small (1 to 5 percent) but statistically significant asymmetries in linear distances were found involving tertiary landmarks (those that are not directly associated with the cleft or adjacent oronasal area). Most linear distances involving the nasion, zygomaxillare superius, and frontozygomatic junction were significantly greater on the cleft side, and certain linear distances in and around the middle cranial fossa were significantly smaller on the cleft side., Conclusions: The extreme asymmetry of primary and secondary landmarks is explained by the cleft itself and the obvious displacement of the premaxilla toward the noncleft side. The subtler, statistically significant asymmetry of the tertiary landmarks supports the idea that the unilateral cleft affects development of the entire face and possibly the cranial base. Euclidean distance matrix analysis of computed tomography landmark data is a useful methodology for the quantitative morphometry of children with untreated unilateral cleft lip and palate.

Nontraditional or geometric morphometric methods have found wide application in the biological sciences, especially in anthropology, a field with a strong history of measurement of biological form. Controversy has arisen over which method is the "best" for quantifying the morphological difference between forms and for making proper statistical statements about the detected differences. This paper explains that many of these arguments are superfluous to the real issues that need to be understood by those wishing to apply morphometric methods to biological data. Validity, the ability of a method to find the correct answer, is rarely discussed and often ignored. We explain why demonstration of validity is a necessary step in the evaluation of methods used in morphometrics. Focusing specifically on landmark data, we discuss the concepts of size and shape, and reiterate that since no unique definition of size exists, shape can only be recognized with reference to a chosen surrogate for size. We explain why only a limited class of information related to the morphology of an object can be known when landmark data are used. This observation has genuine consequences, as certain morphometric methods are based on models that require specific assumptions, some of which exceed what can be known from landmark data. We show that orientation of an object with reference to other objects in a sample can never be known, because this information is not included in landmark data. Consequently, a descriptor of form difference that contains information on orientation is flawed because that information does not arise from evidence within the data, but instead is a product of a chosen orientation scheme. To illustrate these points, we apply superimposition, deformation, and linear distance-based morphometric methods to the analysis of a simulated data set for which the true differences are known. This analysis demonstrates the relative efficacy of various methods to reveal the true difference between forms. Our discussion is intended to be fair, but it will be obvious to the reader that we favor a particular approach. Our bias comes from the realization that morphometric methods should operate with a definition of form and form difference consistent with the limited class of information that can be known from landmark data. Answers based on information that can be known from the data are of more use to biological inquiry than those based on unjustifiable assumptions.