The chondrocranium provides the key initial support for the fetal brain, jaws and cranial sensory organs in all vertebrates. The patterns of shaping and growth of the chondrocranium set up species-specific development of the entire craniofacial complex. The 3D development of chondrocranium have been studied primarily in animal model organisms, such as mice or zebrafish. In comparison, very little is known about the full 3D human chondrocranium, except from drawings made by anatomists many decades ago. The knowledge of human-specific aspects of chondrocranial development are essential for understanding congenital craniofacial defects and human evolution. Here advanced microCT scanning was used that includes contrast enhancement to generate the first 3D atlas of the human fetal chondrocranium during the middle trimester (13 to 19 weeks). In addition, since cartilage and bone are both visible with the techniques used, the endochondral ossification of cranial base was mapped since this region is so critical for brain and jaw growth. The human 3D models are published as a scientific resource for human development.

• MeSH
• Cartilage diagnostic imaging   embryology   MeSH
• Skull diagnostic imaging   embryology   MeSH
• Humans MeSH
• Fetus diagnostic imaging   MeSH
• X-Ray Microtomography MeSH
• Pregnancy MeSH
• Imaging, Three-Dimensional * MeSH
• Check Tag
• Humans MeSH
• Pregnancy MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Dataset MeSH

The complex shape of embryonic cartilage represents a true challenge for phenotyping and basic understanding of skeletal development. X-ray computed microtomography (μCT) enables inspecting relevant tissues in all three dimensions; however, most 3D models are still created by manual segmentation, which is a time-consuming and tedious task. In this work, we utilised a convolutional neural network (CNN) to automatically segment the most complex cartilaginous system represented by the developing nasal capsule. The main challenges of this task stem from the large size of the image data (over a thousand pixels in each dimension) and a relatively small training database, including genetically modified mouse embryos, where the phenotype of the analysed structures differs from the norm. We propose a CNN-based segmentation model optimised for the large image size that we trained using a unique manually annotated database. The segmentation model was able to segment the cartilaginous nasal capsule with a median accuracy of 84.44% (Dice coefficient). The time necessary for segmentation of new samples shortened from approximately 8 h needed for manual segmentation to mere 130 s per sample. This will greatly accelerate the throughput of μCT analysis of cartilaginous skeletal elements in animal models of developmental diseases.

• MeSH
• Cartilage diagnostic imaging   MeSH
• Deep Learning * MeSH
• Mice MeSH
• Neural Networks, Computer MeSH
• Image Processing, Computer-Assisted methods   MeSH
• X-Rays MeSH
• Developmental Biology MeSH
• Animals MeSH
• Check Tag
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

Squamate reptiles are considered to exhibit indeterminate growth. Nevertheless, current literature disputes the available definitions of this growth type, presents new theoretical models, and questions its universality in cold-blooded vertebrates. We have followed up on our previous research employing micro-CT to explore growth plate cartilage (GPC) in the epiphysis of long bones, which is responsible for longitudinal skeletal growth by the endochondral ossification process. We focused on numerous and highly diversified group of the Iguania clade comprising Acrodonta (agamas and chameleons) and Pleurodonta ("iguanas"). We recorded the absence of GPC in most of the examined adult Pleurodonta specimens and interpret it as an irreversible arrest of skeletal growth. This finding clearly rejects the universality of indeterminate growth in lizards. On the other hand, we found apparent GPC preservation in most of the adult specimens belonging to Acrodonta. This suggests a preserved ability to continue body growth throughout most of their life. We discuss the uncovered disparity between Acrodonta and Pleurodonta and emphasize the importance of GPC degradation timing.

• MeSH
• Cartilage * diagnostic imaging   growth & development   MeSH
• Phylogeny * MeSH
• Lizards metabolism   MeSH
• X-Ray Microtomography * MeSH
• Growth Plate * diagnostic imaging   growth & development   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

BACKGROUND: Specific attention on the musculoskeletal impact of wearing high-heeled shoes (HHS) has mainly focused on knee osteoarthritis and the literature is limited to biomechanical changes. The distal femoral cartilage has not been morphologically studied. Additionally, although heel elevation is coupled with a shear stress at the heel and overloaded calf muscles, Achilles tendon (AT) and plantar fascia (PF) thicknesses have not been assessed either. OBJECTIVE: To investigate whether the distal femoral cartilage, AT, and PF were different in women wearing HHS and flat-heeled shoes (FHS) and specifically, different in terms of AT/PF and distal femoral cartilage thicknesses. DESIGN: Cross-sectional observational study. SETTING: Tertiary care center. PARTICIPANTS: There were 34 women (mean age; 31.1 ± 6.4, body mass index [BMI]; 21.6 ± 2.4 kg/m2 ) in the HHS group and 54 women (mean age; 29.5 ± 7.2 years, BMI 22.5 ± 2.9 kg/m2 ) in the FHS group (P = .271, P = .102, respectively). Women wearing shoes with a heel height of >5 cm were enrolled in the HHS group, and those wearing shoes with a heel height of <1.4 cm were included in the FHS group. MAIN OUTCOME MEASUREMENTS: Distal femoral cartilage from the lateral condyle, intercondylar area and medial condyle (MFC), AT and PF thicknesses, and any abnormalities were evaluated bilaterally by ultrasound. RESULTS: Within-group comparisons yielded thicker right MFC (P = .022) and left AT (P = .028) only in the HHS group. Between-group comparisons yielded thicker left AT in the HHS group (P = .040). PF thicknesses were similar both within and between group comparisons (all P > .05). Right AT thickness was positively correlated with right (r = .469, P = .005) and left (r = .402, P = .018) PF thicknesses only within the HHS group. Only calcaneal irregularity/spur was found to be common in the HHS group (P = .038). CONCLUSIONS: We found thickening of the right MFC and left AT in those wearing HHS, whereas PF thickness was not significantly different between those wearing HHS and those wearing FHS. LEVEL OF EVIDENCE: III.

• MeSH
• Achilles Tendon diagnostic imaging   MeSH
• Aponeurosis diagnostic imaging   MeSH
• Cartilage diagnostic imaging   MeSH
• Adult MeSH
• Humans MeSH
• Foot diagnostic imaging   MeSH
• Shoes adverse effects   MeSH
• Cross-Sectional Studies MeSH
• Ultrasonography MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Observational Study MeSH
• Comparative Study MeSH