Novel bio-imaging techniques such as micro-Computed Tomography provide an opportunity to investigate animal anatomy and morphology by overcoming limitations imposed by traditional anatomical drawings. The primate genital bones are complex anatomical structures whose occurrence in both male penis (baculum) and female clitoris (baubellum) may be difficult to assess in individual cadavers. We tested a 3-step methodological protocol, including different techniques ranging from inexpensive/simple to more expensive/sophisticated ones, by applying it to a sample of primate species, and resulting in different levels of data complexity: (1) presence/absence manual palpation method; (2) 2D X-ray plates; 3) 3D micro-CT scans. Manual palpation failed on 2 out of 23 specimens by detecting 1 false negative and 1 false positive; radiography failed once confirming the false positive, however firmly disproved by micro-CT; micro-CT analysis reported the presence of 9 bacula out of 11 male specimens and 1 baubellum out of 12 female specimens. A different baculum position was identified between strepsirrhine and haplorrhine species. We also aim to assess micro-CT as a non-invasive technique providing updated anatomical descriptions of primate ossa genitalia. Micro-CT 3D volumes showed the surface of some bones as rough, with a jagged appearance, whereas in others the surface appeared very smooth and coherent. In addition, four main types of bone internal structure were identified: 1) totally hollow; 2) hollow epiphyses and solid diaphysis with few or several channels inside; 3) totally solid with intricate Haversian channels; 4) totally solid with some channels (structure of single baubellum scanned). Ossa genitalia appeared as a living tissue having its own Haversian-like channels. The high resolution of micro-CT 3D-images of primate genital bones disclosed additional form variability to that available from genital bone 2D images of previous studies, and showed for the first time new internal and external morphological characters. Moreover, micro-CT non-invasive approach proved appropriate to recover much of scientific knowledge still hidden and often neglected in both museum specimens and primate cadavers only destined to necropsy.Novel radiological techniques have greatly advanced our knowledge in animal morphology, allowing to quantify internal anatomy with higher degree of accuracy, also using non-invasive approaches. In the past, anatomical studies were based on bi-dimensional drawings and/or photographs that allow to obtain limited information about size and shape. To date, bio-imaging techniques overcome these methodological limits since they produce virtual 3D models which, in addition, provide the access to more detailed descriptors of morphological variation. The availability of micro-CT imaging has increased over the last decade and has shown its utility in many biological [1-3] and medical applications [4][5][6]. In comparison with other imaging techniques, the strengths of micro-CT lie in its high-resolution imaging, s...

Investigations on asymmetries showed that deviations from perfect bilateral symmetry are interpreted as environmental changes inducing developmental instability. Since morphological abnormalities increase with pollution, deformations may be considered indicators of the organism exposition to pollution. Therefore, the onset of asymmetry in otherwise normally symmetrical traits has been used as a measure of some stresses as well. In this context, we studied how marine pollution affects the valve morphological alterations in the mussel Mytilus galloprovincialis. We used 180 specimens (30 per site) from the aquaculture area of Goro (River Po delta, northern Adriatic Sea), translocated, and released within 50 × 50 × 50 cm cages in five sites: two disturbed and one undisturbed near Naples (eastern Tyrrhenian Sea), and one disturbed and one undisturbed near Siracusa (western Ionian Sea). Disturbed sites were stressed by heavy industrialization and heavy tankers traffic of crude and refined oil, and were defined basing on sediment contamination. In particular, by the cone-beam computed tomography we obtained 3D virtual valve surfaces to be analyzed by the geometric morphometric techniques. Specifically, we focused the levels of the shell shape fluctuating asymmetry in relation to the degrees of marine pollution in different sites of the Tyrrhenian Sea. The Mahalanobis distances (interpreted as proxy of the individual shape asymmetry deviation from the mean asymmetry) significantly regressed with the sediment contamination gradient. Indeed, although the left-right differences were normally distributed in each studied site, the individual asymmetry scores (IAS) significantly varied amongst the investigated sites. IAS showed higher values in disturbed areas than those of undisturbed ones in both Tyrrhenian and Ionian Sea. Our results are consistent with past studies on molluscans and other taxa, demonstrating some detrimental effects of chemicals on organisms, although the investigated morphological marker did not discriminate the real disturbance source. Our findings indicate that the mussels act as a prognostic tool for sea pollution levels driving detrimental effects on benthic community.

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Crabs are considered exceptional examples of antisymmetry resulting from the phenomenon of heterochely. Here we investigate morphometrically both the size and the shape of heterochely in 28 crab species, distributed unequally along a brachyuran phylogeny. We address the importance of investigating claw size and shape for interspecific comparisons by linking geometric morphometric outputs to phylogenetic data for 134 brachyuran species. New indices introduced as new sexual dimorphic characters of size and shape, namely heterometry (right chela size/left chela size) and heteromorphy (Procrustes distance between right and left chelae shape), revealed sexually dimorphic differences in diverse crab species. We demonstrate that both size and shape heterochely occur amongst the examined species, but there are no ecological correlations. Our study demonstrates that claw similarity between two or more species was due mainly to phylogenetic relatedness rather than ecological convergence, suggesting that claw morphological features could be useful morphological markers in phylogenetic studies. Although further investigation is needed, this study represents one of the first to thoroughly analyse the origin and evolution of heterochely within the Brachyura clade.

The aim of this study was to assess the presence of detectable changes of skin thickness on clinical brain magnetic resonance imaging (MRI) scans in patients with MS, history of multiple gadolinium-based contrast agents (GBCAs) administrations, and evidence of gadolinium deposition in the brain. Materials and Methods: In this observational cross-sectional study, 71 patients with MS who underwent conventional brain MRI with an imaging protocol including enhanced 3D volumetric interpolated breath-hold examination (VIBE) T1-weighted with fat saturation were assessed. Patients with bilateral isointense dentate nucleus on unenhanced T1-weighted images were assigned to group A (controls without MRI evidence of gadolinium deposition), and patients with visually hyperintense dentate nuclei were assigned to group B. Qualitative and quantitative assessment of the skin thickness were performed. Results: Group A included 27 patients (median age, 33 years [IQR,[27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46]; 20 women), and group B included 44 patients (median age, 42 years [IQR,[35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53]; 29 women). Qualitative and quantitative assessment of the skin revealed significant differences between group A and group B. The average skin-to-scalp thickness ratios was significantly higher in group B than in group A (mean ± standard deviation = 0.52 ± 0.02 in group B vs 0.41 ± 0.02 in group A, P < 0.0001) and showed a positive correlation with the total number of enhanced MRI scans (r = 0.39; 95% confidence interval, 0.17-0.57, P < 0.01). Conclusions: Brain MRI detects increased skin thickness of the scalp in patients with MS and dentate nucleus high signal intensity on unenhanced T1-weighted images and shows positive association with previous exposures to linear GBCAs rather than macrocyclic GBCAs.