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Parietal Bones (parietal + bone)

Distribution by Scientific Domains

Medical Sciences	63%
Life Sciences	26%
2 Other Domains	11%

Selected Abstracts

Origin matters: Differences in embryonic tissue origin and Wnt signaling determine the osteogenic potential and healing capacity of frontal and parietal calvarial bones

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 7 2010
Natalina Quarto
Abstract Calvarial bones arise from two embryonic tissues, namely, the neural crest and the mesoderm. In this study we have addressed the important question of whether disparate embryonic tissue origins impart variable osteogenic potential and regenerative capacity to calvarial bones, as well as what the underlying molecular mechanism(s). Thus, by performing in vitro and in vivo studies, we have investigated whether differences exist between neural crest,derived frontal and paraxial mesodermal,derived parietal bone. Of interest, our data indicate that calvarial bone osteoblasts of neural crest origin have superior potential for osteogenic differentiation. Furthermore, neural crest,derived frontal bone displays a superior capacity to undergo osseous healing compared with calvarial bone of paraxial mesoderm origin. Our study identified both in vitro and in vivo enhanced endogenous canonical Wnt signaling in frontal bone compared with parietal bone. In addition, we demonstrate that constitutive activation of canonical Wnt signaling in paraxial mesodermal,derived parietal osteoblasts mimics the osteogenic potential of frontal osteoblasts, whereas knockdown of canonical Wnt signaling dramatically impairs the greater osteogenic potential of neural crest,derived frontal osteoblasts. Moreover, fibroblast growth factor 2 (FGF-2) treatment induces phosphorylation of GSK-3, and increases the nuclear levels of ,-catenin in osteoblasts, suggesting that enhanced activation of Wnt signaling might be mediated by FGF. Taken together, our data provide compelling evidence that indeed embryonic tissue origin makes a difference and that active canonical Wnt signaling plays a major role in contributing to the superior intrinsic osteogenic potential and tissue regeneration observed in neural crest,derived frontal bone. © 2010 American Society for Bone and Mineral Research [source]

Machinery-Related Deaths: Relevance of Workplace Investigation and Antemortem Radiological Data in Reconstructing the Fatality

JOURNAL OF FORENSIC SCIENCES, Issue 3 2010
Giovanni Cecchetto M.D.
Abstract:, Machinery-related fatalities are one of the leading causes of traumatic occupational deaths. In our report, we present the case of a 40-year-old male who suffered a severe head trauma while working in a cut-foam industry and died despite an early craniectomy. The radiological reconstruction of the skull based on preoperative computed tomography scans disclosed a large depressed conical fracture of the left parietal bone. The 3D-reconstruction of the work area, combined with a fit-matching analysis between the machinery and the depressed skull fracture allowed us to conclude that the head was crushed between the sliding bar of the cutting device and the metallic protuberance on the opposite side. The case underlines the importance of a detailed workplace investigation and of a thorough evaluation of all circumstantial, clinical, radiological, and autopsy data in the reconstruction of machinery-related fatalities to identify any possible legal responsibilities of the worker and/or the employer. [source]

Chiari-like malformation in the Griffon Bruxellois

JOURNAL OF SMALL ANIMAL PRACTICE, Issue 8 2009
C. Rusbridge
Objectives: This study describes Chiari-like malformation and syringomyelia in the Griffon Bruxellois and establishes if skull radiographs are useful for disease prediction. Methods: Magnetic resonance imaging from 56 Griffon Bruxellois dogs was assessed for Chiari-like malformation and cerebrospinal fluid pathway abnormalities. Skull radiographs were obtained in 33 dogs. Two rostrocaudal and two ventrodorsal measurements were made, and ratios of one length to another were compared. Results: In this selected sample, 60·7 per cent had Chiari-like malformation. Syringomyelia occurred with and without Chiari-like malformation (37·5 and 8·9 per cent study population, respectively). The radiographic study demonstrated that one measurement ratio could be used to predict Chiari-like malformation (sensitivity of 87 per cent and specificity of 78 per cent) and that there were significant interaction factors between sex and syringomyelia for two measurement ratios. Clinical Significance: The study suggests that Chiari-like malformation is characterised by a shortening of the basicranium and supra-occipital bone with a compensatory lengthening of the cranial vault, especially the parietal bone. We described a simple radiographic technique, which may be useful as a screening test until a more definite genetic test for Chiari-like malformation is available. [source]

Monitoring angiogenesis in soft-tissue engineered constructs for calvarium bone regeneration: an in vivo longitudinal DCE-MRI study

NMR IN BIOMEDICINE, Issue 1 2010
Marine Beaumont
Abstract Tissue engineering is a promising technique for bone repair and can overcome the major drawbacks of conventional autogenous bone grafting. In this in vivo longitudinal study, we proposed a new tissue-engineering paradigm: inserting a biological soft-tissue construct within the bone defect to enhance angiogenesis for improved bone regeneration. The construct acts as a resorbable scaffold to support desired angiogenesis and cellular activity and as a vector of vascular endothelial growth factor, known to promote both vessel and bone growth. Dynamic contrast- enhanced magnetic resonance imaging was performed to investigate and characterize angiogenesis necessary for bone formation following the proposed paradigm of inserting a VEGF-impregnated tissue-engineered construct within the critical-sized calvarial defect in the membranous parietal bone of the rabbit. Results show that a model-free quantitative approach, the normalized initial area under the curve metric, provides sensitive and reproducible measures of vascularity that is consistent with known temporal evolution of angiogenesis during bone regeneration. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Inheritance of sutural pattern at the pterion in rhesus monkey skulls

THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 10 2006
Qian Wang
Abstract Five of the bones that characteristically comprise the cranial vault articulate on the lateral aspect of the skull at or near the cephalometric landmark referred to as the pterion. The pattern of articulation in the sutures associated with these bones varies among and within primate species and has been used as a criterion for classification in taxonomic studies, as well as in archeological and forensic studies. Within species, the sutural patterns found within the region of the pterion have remarkable consistency, which lead to the hypothesis that these patterns have a genetic basis. Sutural pattern variations were investigated at the pterion in 422 skulls from 66 rhesus monkey families with known genealogies from the long-standing colony on Cayo Santiago. Four specific types of articulation patterns were recorded. The results demonstrated that the most common suture pattern at the pterion of Cayo Santiago rhesus monkeys (86%; similar to that seen in some other anthropoid species but not humans and some apes) was characterized by an articulation between the temporal bone and parietal bone. Articulation between the sphenoid and parietal bones (type SP) accounted for 14% of the specimens and was concentrated in a dozen families. Mothers with the SP phenotype had a high incidence of offspring with SP phenotypes. Most non-SP mothers having SP offspring had siblings or family members from previous generations with the SP type. This is the first study to examine variation in sutural patterns at the pterion in pedigrees. Variation of sutural patterns shows familial aggregation, suggesting that this variation is heritable. Future work will be focused on defining the inheritance patterns of variation at the pterion, with the ultimate objective of identifying the specific genes involved and their mechanism of action. Anat Rec Part A, 288A:1042,1049, 2006. © 2006 Wiley-Liss, Inc. [source]

EFFECTS OF VITAMIN E AND SESAMIN ON HYPERTENSION AND CEREBRAL THROMBOGENESIS IN STROKE-PRONE SPONTANEOUSLY HYPERTENSIVE RATS

CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 2004
Takanori Noguchi
SUMMARY The preventive effects of sesamin, a lignan from sesame oil and vitamin E on hypertension and thrombosis were examined using stroke-prone spontaneously hypertensive rats (SHRSP). Animals at 5 weeks of age were separated into four groups: (i) control group; (ii) vitamin E group, which was given 1000 mg alpha-tocopherol/kg diet; (iii) sesamin group, given 1000 mg sesamin/kg diet; and (iv) vitamin E plus sesamin group, given 1000 mg alpha-tocopherol plus 1000 mg sesamin/kg diet for 5 weeks from 5 to 10 weeks of age. Resting blood pressure was measured by the tail-cuff method once weekly. A closed cranial window was created in the right parietal bone of the rat and platelet-rich thrombi were induced in vivo using a helium-neon laser technique. The number of laser pulses required for formation of an occlusive thrombus was used as an index of thrombotic tendency. In control rats, systolic blood pressure and the amount of urinary 8-hydroxy-2,-deoxyguanosine (8-OHdG) became significantly elevated with age. However, the elevation in blood pressure and 8-OHdG were significantly suppressed in rats administered vitamin E, sesamin, or vitamin E plus sesamin. At 10 weeks, the number of laser pulses required to induce an occlusive thrombus in arterioles of the control group was significantly lower than in the other groups (P < 0.05). These results indicate that chronic ingestion of vitamin E and sesamin attenuated both elevation in blood pressure, oxidative stress and thrombotic tendency, suggesting that these treatments might be beneficial in the prevention of hypertension and stroke. [source]

Bone morphology and vascularization of untreated and guided bone augmentation-treated rabbit calvaria: evaluation of an augmentation model

CLINICAL ORAL IMPLANTS RESEARCH, Issue 2 2005
Christer Slotte
Abstract Objectives: Cranial vault is widely used in experimental models on membranous bone healing in general, guided bone augmentation (GBA) studies being one example. To our knowledge, however, few studies on the characteristics of the untreated calvaria regarding bone density, vessel topography, and their intra/interindividual variations and associations are available. The aims of this investigation were to (1) map the large vessel topography of the skull vault, (2) describe the parietal bones of the adult rabbit histologically and morphometrically, and (3) histologically compare untreated parietal bone with parietal bone that had been treated with a GBA device. Material and methods: Ten adult untreated rabbits were microangiographed. General anesthesia was induced and the mediastinum was opened. Heparin and lidocaine were injected in the aorta followed by perfusion with India ink. After death, en bloc biopsies of the skull vault including the overlying soft tissues and dura mater were taken. The specimens were cleared with the Spalteholtz technique, microscopically examined, and digitally imaged. Thereafter, circular biopsies were harvested to obtain decalcified sections. In addition, sections from 14 GBA-treated rabbit skulls (of the same race, sex and age as the untreated animals) served as reference specimens for comparison. Histomorphometric examinations were carried out. Results: In the cleared specimens, all parietal bones were found to be supplied by one major branch of the meningeal artery. From each of these, separate branches supplied the dura wherein a fine vessel network covered the bone. No major vessels were found in the supracalvarial soft tissue. Numerous fine vessels were found within the periosteum and dura entering the cortical plates. The decalcified sections of the parietal bones revealed an outer and inner cortical plate enveloping a diploic space containing bone trabeculae, marrow tissue and larger sinusoids. Hollow connections were frequently found in both the outer and inner cortical plates in both the untreated and the GBA-treated specimens. These connections contained marrow tissue that extended to the periosteum and the dura. The morphometric measurements revealed similar proportions of cortical, trabecular, and marrow areas in the right and left untreated bones. The area of the outer cortical plate was significantly larger than the area of the inner cortical plate. Bone density was similar in the right and left untreated and GBA-treated specimens, as was the frequency and width of hollow connections through the cortical bone plates. Conclusions: The symmetry between the left and right parietal bones concerning the large vessel topography and the histomorphometric parameters assessed was high. Hollow connections in the cortical plates were frequently found. The bilateral use of the parietal bones is suggested to be reliable in experimental GBA models regarding the blood supply and bone quality. Résumé La voûte crânienne est souvent utilisée dans les modèles expérimentaux de guérison osseuse membranaire en général, l'augmentation osseuse guidée (GBA) étant un exemple. Peu d'études sur les crânes non-traités sont disponibles en ce qui concerne la densité osseuse, la topographie des vaisseaux et leurs variations intra/interindividuelles et leurs associations. Les buts de cette étude ont été 1) de cartographier la topographie des vaisseaux larges sur la voute crânienne, 2) de décrire les os pariétaux du lapin adulte histologiquement et morphométriquement et 3) de comparer histologiquement l'os pariétal non-traité avec celui traité par GBA. Dix lapins adultes non-traités ont subi une micro-angiographie. L'anesthésie générale a été effectuée et la partie médiane a été ouverte. De l'héparine et de la lidocaïne ont été injectées dans l'aorte suivies d'une perfusion avec de l'encre noire. Après la mort, des biopsies en blocs de la voûte crânienne comportant la dura mater et les tissus mous la recouvrant ont été prélevées. Les spécimens ont été estimés par la technique de Spalteholtz, examinés microscopiquement et des images digitales ont été réalisées. Des biopsies circulaires ont été prélevées pour obtenir des sections décalcifiées. Des sections de 14 crânes de lapins traités GBA (de même race, sexe et âge que les non-traités) ont servi de spécimens de référence pour comparaison. Des examens histomorphométriques ont été effectués. Dans les spécimens non-traités, tous les os pariétaux étaient irrigués par une branche majeure de l'artère méningée. De chacune de ces dernières, différentes branches abreuvaient la dura dans laquelle un réseau de vaisseau fins recouvrait l'os. Aucun vaisseau majeur n'a été trouvé dans le tissu mou ou sus-voûte. De nombreux vaisseaux fins ont été trouvés à l'intérieur du périoste et de la dura pénétrant qu'entre les bords corticaux. Les sections décalcifiées des os pariétaux ont révélé des bords corticaux interne et externe enveloppant un espace diploïque contenant de l'os trabéculaire, de la moelle osseuse et de larges sinusoïdes. Des connexions creuses étaient fréquemment trouvées tant dans les plaques corticales interne qu'externe et tant dans les spécimens non-traités que traités GBA. Ces connexions contenaient de la moelle qui allait jusqu'au périoste et la dura. Les mesures morphométriques ont révélé des proportions semblables de cortical, trabécules et moelle dans les les os non-traités. L'aire du bord cortical externe était significativement plus importante que l'aire du bord cortical interne. La densité osseuse était semblable dans les spécimens non-traités et traités GBA gauches et droits ainsi que la fréquence et la largeur des connexions creuses à travers les bords osseux corticaux. La symétrie entre les os pariétaux gauches et droits concernant la topographie des vaisseux larges et des paramètres histomorphométriques étaient importante. Les connexions creuses dans les bords corticaux était souvent trouvées. L'utilisation bilatérale des os pariétaux est proposée pour sa fiabilité dans les modèles GBA expérimentaux concernant l'apport sanguin et la qualité osseuse. Zusammenfassung Ziele:,Die Schädeldecke wird oft bei experimentellen Modellen zur bindegewebigen Knochenheilung verwendet. Ein Beispiel dafür sind Studien zur gesteuerten Knochenaugmentation (GBA). Soviel wir wissen, existieren jedoch nur wenige Studien über die Charakteristiken der unbehandelten Kalvaria bezüglich Knochendichte, Gefässtopographie und deren intra-/interindividuelle Variationen und Assoziationen. Die Ziele dieser Untersuchung waren (1) die Topographie der grossen Gefässe der Schädeldecke aufzuzeichnen, (2) die parietalen Knochen des ausgewachsenen Kaninchens histologisch und histomorphometrisch zu beschreiben, und (3) histologisch den unbehandelten parietalen Knochen mit parietalem Knochen, der mit einer GBA Einrichtung behandelt worden war, zu vergleichen. Material und Methoden:,Zehn ausgewachsene Kaninchen wurden mikroangiographisch untersucht. In Narkose wurde das Mediastinum eröffnet. Es wurde Heparin und Lidocain in die Aorta injiziert, darauf folgte die Perfusion mit India Tinte. Nach dem Tod wurden Blockbiopsien der Schädeldecke inklusive bedeckende Weichgewebe und Dura mater entnommen. Die Präparate wurden mittels der Spaltenholztechink gereinigt, mikroskopisch untersucht und digital aufgezeichnet. Danach wurden zirkuläre Biopsien gewonnen, um entkalkte Schnitte herzustellen. Zusätzlich dienten Schnitte von 14 GBA-behandelten Kaninchenschädeln (gleiche Rasse, Geschlecht und Alter wie die unbehandelten Tiere) als Referenzpräparate zum Vergleich. Es wurden histomorphometrische Untersuchungen durchgeführt. Resultate:,In den gereinigten Präparaten konnte gesehen werden, dass alle parietalen Knochen durch einen grossen Ast der Meningalarterie versorgt wurden. Separate Aeste dieser Arterie versorgten die Dura, wobei ein feines Gefässnetz den Knochen bedeckte. In den Weichgeweben auf der Kalvaria konnten keine grossen Gefässe gefunden werden. Im Periost und in der Dura waren zahlreiche feine Gefässe zu sehen, welche in die kortikalen Platten eintraten. Die entkalkten Schnitte der parietalen Knochen zeigten eine äussere und innere kortikale Platte, welche einen abgeschlossenen Raum mit Knochentrabekeln, Markgewebe und grossen Hohlräumen umschlossen. In der inneren und in der äusseren kortikalen Platte konnten oft sowohl bei den unbehandelten als auch bei den GBA-behandelten Präparaten hohle Verbindungen gefunden werden. Diese Verbindungen enthielten Markgewebe, dass sich bis zum Periost und der Dura erstreckte. Die morphometrischen Messungen zeigten sowohl in den rechten als auch in den linken unbehandelten Knochen ähnliche Proportionen zwischen kortikalem Knochen, trabekulärem Knochen und den Markarealen. Die Fläche der äusseren kortikalen Platte war signifikant grösser als die Fläche der inneren kortikalen Platte. Die Knochendichte war in den rechten und linken unbehandelten und in den GBA-behandelten Präparaten ähnlich, ebenso die Häufigkeit und die Breite der hohlen Verbindungen durch die kortikalen Platten. Schlussfolgerungen:,Die Symmetrie zwischen den rechten und linken parietalen Knochen bezüglich Topographie der grossen Gefässe und der untersuchten histomorphometrischen Parameter war gross. In den kortikalen Platten konnten häufig hohle Verbindungen gefunden werden. Es wird vorgeschlagen, dass die bilaterale Verwendung von parietalen Knochen bei experimentellen GBA-Modellen zuverlässig ist bezüglich Blutversorgung und Knochenqualität. Resumen Objetivos:,La bóveda craneal es ampliamente usada en modelos experimentales en cicatrización de hueso membranoso en general, siendo un ejemplo los estudios de regeneración ósea guiada (GBA). Que sepamos, sin embargo, se dispone de pocos estudios sobre las características del calvario no tratado con respecto a la densidad ósea, la topografía vascular, y sus variaciones intra/interindividuo y sus asociaciones. Las intenciones de esta investigación fueron (1) cartografiar la topografía de grandes vasos de la bóveda craneal, (2) describir histológica y morfométricamente los huesos parietales del conejo adulto, y (3) comparar histológicamente el hueso parietal no tratado con el hueso parietal tratado con un dispositivo de GBA. Material y Métodos:,Se llevaron a cabo microangiografías a diez conejos adultos sin tratar. Se indujo anestesia general y se abrió el mediastino Se inyectaron heparina y lidocaina en la aorta seguida por infusión de tinta de India. Tras la muerte, se tomaron biopsias en bloque de la bóveda craneal incluyendo los tejidos blandos superpuestos y de la duramadre. Los especimenes se aclararon con la técnica de Spalteholtz, se examinaron microscópicamente, y se tomaron imágenes digitales. Más adelante, se recogieron biopsias circulares para obtener secciones descalcificadas. Además, secciones de los cráneos de los conejos tratados con 14secciones descalcificadas. Además, secciones de los cráneos de los conejos tratados con 14 GBA (de la misma raza, sexo y edad que los animales no tratados) sirvieron como especimenes de referencia para la comparación. Se llevaron a cabo exámenes histomorfométricos. Resultados:,En los especimenes aclarados, todos los huesos parietales se encontró que estaban irrigados por una rama principal de la arteria meníngea. De cada una de estas, ramas separadas irrigaron la dura en donde una fina red de vasos cubrió el hueso. No se encontraron vasos mayores en el tejido blando supracalvario. Se encontraron numerosos vasos dentro del periostio y la dura entrando en las placas corticales. Las secciones descalcificadas de los huesos parietales revelaron una placa cortical interna y externa envolviendo un espacio diploico conteniendo trabéculas óseas, tejido medular y grandes sinusoides. Frecuentemente se encontraron conexiones huecas en las placas corticales internas y externas tanto en los especimenes sin tratar como en los tratados con GBA. Estas conexiones contenían tejido medular que se extendió hasta el periostio y la dura. Las medidas morfogenéticas revelaron proporciones similares de áreas corticales trabeculares y medulares en los huesos derecho e izquierdo no tratados. El área de la placa cortical externa fue significativamente mayor que el área de placa cortical interna. La densidad ósea fue similar en el lado derecho e izquierdo no tratados y en los especimenes tratados con GBA, así como la frecuencia y la anchura de las conexiones huecas a lo largo de las placas óseas corticales. Conclusiones:,La simetría entre los huesos parietales izquierdos y derechos concernientes a la topografía vascular y los parámetros histomorfométricos valorados fue alta. Las conexiones huecas en las placas corticales se encontraron con frecuencia. Se sugiere que el uso bilateral de huesos parietales es fiable como modelo experimental GBA respecto al suministro de sangre y calidad ósea. [source]

Hyperostosis cranii in the elderly with various clinical symptoms

GERIATRICS & GERONTOLOGY INTERNATIONAL, Issue 1 2004
Makoto Sohmiya
We report three elderly patients with hyperostosis cranii. Patient 1 had two episodes of unconsciousness; Patient 2, headache; and Patient 3, dementia. On the basis of Moore's classification using skull films, Patients 1 and 2 showed hyperostosis frontoparietalis and Patient 3 had hyperostosis frontalis interna. Electroencephalography showed transient generalized spike and slow wave complexes over the frontal lobes in Patient 1. Magnetic resonance images showed frontal lobes compressed by the thickness of the frontal bones in all patients and the thickness of the parietal bones in Patients 1 and 2. Since the findings in the present cases and those in the literature suggest that hyperostosis cranii could show unexpected neuropsychiatric symptoms, hyperostosis cranii should be checked in elderly patients whose presenting symptoms include epilepsy, dementia, psychiatric disease, headache and so on. Magnetic resonance images should be helpful in examining the relationship between clinical symptoms and the deformation of the brain by the skull. [source]

A probable case of gigantism in a fifth Dynasty skeleton from the Western Cemetery at Giza, Egypt

INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 4 2005
D. M. MulhernArticle first published online: 31 DEC 200
Abstract Pituitary gigantism is a rare endocrine disorder caused by excess secretion of growth hormone during childhood. Individuals with this condition exhibit unusually tall stature due to prolonged growth as well as associated degenerative changes. Continued secretion of excess growth hormone during adulthood results in acromegaly, a related condition that results in bony overgrowth of the skull, hands and feet. The remains of a large adult male, probably in his late 20s or early 30s, from a Fifth Dynasty tomb (2494,2345 BC) were excavated in 2001 from Cemetery 2500 in the Western Cemetery at Giza, Egypt, as part of the Howard University Giza Cemetery Project. This individual exhibits characteristics of pituitary gigantism, including tall but normally-proportioned stature, delayed epiphyseal union, a large sella turcica, advanced arthritis and a transepiphyseal fracture of the left femoral head. Additional pathological features, including osteopenia and thinness of the parietal bones, suggest that this individual may also have been hypogonadal. Craniometric comparisons with other ancient Egyptian groups as well as modern normal and acromegalic patients show some tendency toward acromegalic skull morphology. Differential diagnosis includes eunuchoid gigantism, Sotos syndrome, Beckwith-Wiedemann syndrome, Marfan syndrome, homocystinuria, Weaver syndrome and Klinefelter syndrome. In conclusion, the pathological features associated with this skeleton are more consistent with pituitary gigantism than any of the other syndromes that result in skeletal overgrowth. Copyright © 2004 John Wiley & Sons, Ltd. [source]

Earliest Mineral and Matrix Changes in Force-Induced Musculoskeletal Disease as Revealed by Raman Microspectroscopic Imaging,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 1 2004
Catherine P Tarnowski
Abstract Craniosynostosis, premature fusion of the skull bones at the sutures, is the second most common human birth defect in the skull. Raman microspectroscopy was used to examine the composition, relative amounts, and locations of the mineral and matrix produced in mouse skulls undergoing force-induced craniosynostosis. Raman imaging revealed decreased relative mineral content in skulls undergoing craniosynostosis compared with unloaded specimens. Introduction: Raman microspectroscopy, a nondestructive vibrational spectroscopic technique, was used to examine the composition, relative amounts, and locations of the mineral and matrix produced in mouse skulls undergoing force-induced craniosynostosis. Craniosynostosis, premature fusion of the skull bones at the sutures, is the second most common birth defect in the face and skull. The calvaria, or flat bones that comprise the top of the skull, are most often affected, and craniosynostosis is a feature of over 100 human syndromes and conditions. Materials and Methods: Raman images of the suture, the tips immediately adjacent to the suture (osteogenic fronts), and mature parietal bones of loaded and unloaded calvaria were acquired. Images were acquired at 2.6 × 2.6 ,m spatial resolution and ranged in a field of view from 180 × 210 ,m to 180 × 325 ,m. Results and Conclusions: This study found that osteogenic fronts subjected to uniaxial compression had decreased relative mineral content compared with unloaded osteogenic fronts, presumably because of new and incomplete mineral deposition. Increased matrix production in osteogenic fronts undergoing craniosynostosis was observed. Understanding how force affects the composition, relative amounts, and location of the mineral and matrix provides insight into musculoskeletal disease in general and craniosynostosis in particular. This is the first report in which Raman microspectroscopy was used to study musculoskeletal disease. These data show how Raman microspectroscopy can be used to study subtle changes that occur in disease. [source]

Differential Expression Patterns of Runx2 Isoforms in Cranial Suture Morphogenesis

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 5 2001
Mi-Hyun Park
Abstract Runx2 (previously known as Cbfa1/Pebp2,A/AML3), a key transcription factor in osteoblast differentiation, has at least two different isoforms using alternative promoters, which suggests that the isoforms might be expressed differentially. Haploinsufficiency of the Runx2 gene is associated with cleidocranial dysplasia (CCD), the main phenotype of which is inadequate development of calvaria. In spite of the biological relevance, Runx2 gene expression patterns in developing calvaria has not been explored previously, and toward this aim we developed three probes: pRunx2, which comprises the common coding sequence of Runx2 and hybridizes with all isoforms; pPebp2,A, which specifically hybridizes with the isoform transcribed with the proximal promoter; and pOsf2, which hybridizes with the isoform transcribed with the distal promoter. These probes were hybridized with tissue sections of mouse calvaria taken at various time points in development. Runx2 expression was localized to the critical area of cranial suture closure, being found in parietal bones, osteogenic fronts, and sutural mesenchyme. Pebp2,A and Osf2 showed tissue-specific expression patterns. The sites of Pebp2,A expression were almost identical to that of pRunx2 hybridization but expression was most intense in the sutural mesenchyme, where undifferentiated mesenchymal cells reside. The Osf2 isoform was strongly expressed in the osteogenic fronts, as well as in developing parietal bones, where osteopontin (OP) and osteocalcin (OC) also were expressed. However, in contrast to Pebp2,A, Osf2 expression did not occur in sutural mesenchyme. Pebp2,A also was expressed prominently in primordial cartilage that is found under the sutural mesenchyme and is not destined to be mineralized. Thus, Osf2 isoforms contribute to events later in osteoblast differentiation whereas the Pebp2,A isoform participates in a wide variety of cellular activities ranging from early stages of osteoblast differentiation to the final differentiation of osteoblasts. [source]

Congruence of individual cranial bone morphology and neutral molecular affinity patterns in modern humans

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2009
Noreen von Cramon-Taubadel
Abstract Recent studies have demonstrated that the shape of the human temporal bone is particularly strongly correlated with neutral genetic expectation, when compared against other cranial regions, such as the vault, face, and basicranium. In turn, this has led to suggestions that the temporal bone is particularly reliable in analyses of primate phylogeny and human population history. While several reasons have been suggested to explain the temporal bone's strong fit with neutral expectation, the temporal bone has never systematically been compared against other individual cranial bones defined using the same biological criteria. Therefore, it is currently unknown whether the shapes of all cranial bones possess reliable information regarding neutral genetic evolution, or whether the temporal bone is unique in this respect. This study tests the hypothesis that the human temporal bone is more congruent with neutral expectation than six other individual cranial bones by correlating population affinity matrices generated using neutral genetic and 3D craniometric data. The results demonstrate that while the temporal bone shows the absolute strongest correlation with neutral genetic data compared with all other bones, it is not statistically differentiated from the sphenoid, frontal, and parietal bones in this regard. Potential reasons for the temporal bone's consistently strong fit with neutral expectation, such as its overall anatomical complexity and/or its contribution to the architecture of the basicranium, are examined. The results suggest that future phylogenetic and taxonomic studies would benefit from considering the shape of the entire cranium minus those regions that deviate most from neutrality. Am J Phys Anthropol, 2009. © 2009 Wiley-Liss, Inc. [source]

Button osteoma: Its etiology and pathophysiology

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2002
Vered Eshed
Abstract The present study investigates a circumscribed bony overgrowth on the cranial vault, known as button osteoma (BtO) and referred to here as button lesion (BtL). We discuss its anthropological implications. Data on its histology, location, and population distribution (by age, race, and gender) are provided. Microscopically, BtL is composed of well-organized dense lamellated bone which is poorly vascularized and with very few osteocytes. It forms a dome-shaped roof over an underlying diploeized area which includes the ectocranial table. The frequency of BtL is similar in modern (37.6%) and archaeological (41.1%) populations, in blacks, whites, males, and females, and correlates with age. It is rare in nonhuman primates. Fifty-five percent of the human skulls studied by us had BtL only on the parietal, 23.6% on the frontal, and 3.6% on the occipital bones. Fifteen percent had BtL on both the frontal and parietal bones. No lateral preference was found. Most skulls with BtL (64.1%) had only one lesion, 20.4% had two BtL, and 15.4% demonstrated multiple BtL. The average number of button osteomas on an affected skull was 1.97. The frequency of large osteomas (0.5,1.0 cm) was similar in young and old age groups. The demographic characteristics of BtL, mainly its high frequency among ancient and modern populations, its independence of sex and race, its scarcity in other primates, and the fact that its macro- and microstruture are indicative of an hamartoma (and not an osteoma or exostosis) suggest an evolutionary background to the phenomenon. Am J Phys Anthropol 118:217,230, 2002. © 2002 Wiley-Liss, Inc. [source]

New Insight on the Anatomy and Architecture of the Avian Neurocranium

THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 3 2009
Jesús Marugán-Lobón
Abstract This study aims to disentangle the main features of the avian neurocranium at high taxonomic scales using geometric morphometric tools. When surveying the variation across 60% of avian orders (sampled among 72 individuals), our results verify that the central nervous system has an important influence upon the architecture of the avian neurocranium, as in other very encephalized vertebrates such as mammals. When the avian brain expands relative to the cranial base it causes more "reptilian-like" neurocranial configurations to shape into rounder ones. This rounder appearance is achieved because the cranial base becomes relatively shorter and turns its flexure from concave to convex, at the same time forcing the foramen magnum to reorient ventrally instead of caudally. However, our analyses have also revealed that an important morphological difference between birds resides between the occiput and the cranial roof. This variation was unexpected since it had not been reported thus far, and entertains two plausible interpretations. Although it could be due to a trade-off between the relative sizes of the supraoccipital and the parietal bones, the presence of an additional bone (the intra- or post-parietal) between the latter two bones could also explain the variation congruently. This descriptive insight stresses the need for further developmental studies focused in understanding the evolutionary disparity of the avian neurocranium. Anat Rec, 292:364,370, 2009. © 2009 Wiley-Liss, Inc. [source]