RESUMO
Using morphological, histological, and TEM analyses of the cranium, we provide a detailed description of bone and suture growth in zebrafish. Based on expression patterns and localization, we identified osteoblasts at different degrees of maturation. Our data confirm that, unlike in humans, zebrafish cranial sutures maintain lifelong patency to sustain skull growth. The cranial vault develops in a coordinated manner resulting in a structure that protects the brain. The zebrafish cranial roof parallels that of higher vertebrates and contains five major bones: one pair of frontal bones, one pair of parietal bones, and the supraoccipital bone. Parietal and frontal bones are formed by intramembranous ossification within a layer of mesenchyme positioned between the dermal mesenchyme and meninges surrounding the brain. The supraoccipital bone has an endochondral origin. Cranial bones are separated by connective tissue with a distinctive architecture of osteogenic cells and collagen fibrils. Here we show RNA in situ hybridization for col1a1a, col2a1a, col10a1, bglap/osteocalcin, fgfr1a, fgfr1b, fgfr2, fgfr3, foxq1, twist2, twist3, runx2a, runx2b, sp7/osterix, and spp1/ osteopontin, indicating that the expression of genes involved in suture development in mammals is preserved in zebrafish. We also present methods for examining the cranium and its sutures, which permit the study of the mechanisms involved in suture patency as well as their pathological obliteration. The model we develop has implications for the study of human disorders, including craniosynostosis, which affects 1 in 2,500 live births.
Assuntos
Suturas Cranianas/citologia , Osso Frontal/citologia , Regulação da Expressão Gênica no Desenvolvimento , Osso Occipital/citologia , Osteogênese/genética , Osso Parietal/citologia , Animais , Colágeno/genética , Colágeno/metabolismo , Subunidades alfa de Fatores de Ligação ao Core/genética , Subunidades alfa de Fatores de Ligação ao Core/metabolismo , Suturas Cranianas/crescimento & desenvolvimento , Suturas Cranianas/metabolismo , Osso Frontal/crescimento & desenvolvimento , Osso Frontal/metabolismo , Humanos , Osso Occipital/crescimento & desenvolvimento , Osso Occipital/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteocalcina/genética , Osteocalcina/metabolismo , Osteopontina/genética , Osteopontina/metabolismo , Osso Parietal/crescimento & desenvolvimento , Osso Parietal/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Fator de Transcrição Sp7 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição Twist/genética , Fatores de Transcrição Twist/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismoRESUMO
The purpose of this study was to evaluate the safety, technical success rate, and diagnostic efficacy of drill-assisted axial and appendicular bone biopsies. During a 3-y period, 703 drill-assisted biopsies were performed. The cohort included 54.2% men, with a mean age of 57.6 y ± 17.1. Median lesion volume was 10.9 mL (interquartile range, 3.4-30.2 mL). Lesions were lytic (31.7%), sclerotic (21.2%), mixed lytic and sclerotic (27.7%), or normal radiographic bone quality (19.3%). No complications were reported. The technical biopsy success rate was 99.9%. Crush artifact was present in 5.8% of specimens submitted for surgical pathologic examination, and 2.1% of specimens were inadequate for histologic evaluation.