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Living birds are unique among vertebrates in the formation of a female-specific bone tissue called medullary bone (MB) that is strictly associated with reproductive activity. MB is a rapidly mobilized source of calcium and phosphorus for the production of eggshell. Among living taxa, its skeletal distribution can be highly extensive such that it even exists in the ribs of some species. Due to its ephemeral nature, MB is rarely fossilized and so little is understood with regard to the origin of MB and its skeletal distribution in early taxa. Here we describe a new Early Cretaceous enantiornithine bird, , gen. et. sp. nov., indicating that skeleton-wide distribution of MB appeared early in avian evolution. We suggest that this represents the plesiomorphic condition for the Aves and that the distribution of MB observed among extant neornithines is a product of increased pneumatization in this lineage and natural selection for more efficient distribution of MB.
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http://dx.doi.org/10.1093/nsr/nwz214 | DOI Listing |
Sci Adv
September 2025
Department of Anthropology, Natural History Museum, Burgring 7, 1010 Vienna, Austria.
Age-related deterioration in bone strength among Western humans has been linked with sedentary lifestyles, but the effect remains debatable. We evaluated aging of diaphyseal strength and cortical bone loss in a European Holocene sample of 1881 adult humeri, femora, and tibiae. Diaphyseal aging did not differ between Early and Late Holocene adults, despite their differences in physical activity.
View Article and Find Full Text PDFMedullary thyroid carcinoma (MTC) is a rare neuroendocrine tumor with variable clinical presentation, posing both diagnostic and therapeutic challenges. Disease recurrence is common and may manifest solely as elevated tumor markers in the absence of clinical findings or positive morphological imaging. We present the case of a 56-year-old woman diagnosed with MTC in 2011, treated with total thyroidectomy and adjuvant therapy.
View Article and Find Full Text PDFBMC Oral Health
September 2025
Faculty of Medicine, University of Salamanca, Salamanca, Spain.
Background: For orthodontists, the position of the incisors is a key factor in setting treatment goals. Achieving maximum stability requires that they be positioned in the medullary portion of the alveolar bone, balanced with the lingual and labial musculature. Incorrect orthodontic movements can result in root resorption, dehiscences, or even fenestrations.
View Article and Find Full Text PDFUnfallchirurgie (Heidelb)
September 2025
Klinik für Orthopädie, Unfallchirurgie, Hand und Plastische Chirurgie, Klinikum Fulda, Pacelliallee 4, 36043, Fulda, Deutschland.
The indications for tibial nailing are increasingly extending into periarticular regions, often under critical and challenging soft tissue conditions. Furthermore, due to the demographic development fractures of compromised osteoporotic bone must increasingly be surgically treated.Suprapatellar and parapatellar approaches have emerged as effective alternatives to the traditional infrapatellar approach, which simplify the operative technique of reduction and nail insertion, reduce the duration of intraoperative fluoroscopy time and yield improved reduction outcomes particularly in complex periarticular fractures.
View Article and Find Full Text PDFCureus
July 2025
Anesthesiology and Perioperative Medicine, University of California, Irvine, Medical Center, Orange, USA.
Photodynamic bone stabilization (PBSS) is a minimally invasive technique used in patients with metastatic bone disease who are poor traditional surgery candidates. Although the procedure has a high success rate, we present a fatal case of cardiopulmonary collapse following balloon insufflation during PBSS. The patient had advanced malignancy and preexisting cardiopulmonary conditions and ultimately experienced pulseless electrical activity and hypoxemia.
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