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Cranial Bones (cranial + bone)
Selected AbstractsFirst-trimester sonography: Is the fetus exposed to high levels of acoustic energy?,JOURNAL OF CLINICAL ULTRASOUND, Issue 5 2007Eyal Sheiner MD Abstract Purpose. As a form of energy, diagnostic ultrasound has bioeffects on living tissues. The thermal index (TI), TIS (TI for soft tissue), TIB (TI for bone), TIC (TI for cranial bone) expresses the potential for rise in temperature at the ultrasound beam's focal point. The mechanical index (MI) indicates the potential for the ultrasound beam to induce inertial cavitation in tissues. The goal of this study was to characterize the acoustic output of clinical ultrasound instruments, as expressed by TI and MI, during routine first-trimester sonographic examinations. Methods. A prospective observational study was conducted. First-trimester patients were randomly selected from those scheduled for viability scans. An obstetrician collected data. Sonographers were blinded to the data being sought, which included gestational age, duration of the examination, and every variation in the MI and TI during each sonographic examination. Results. A total of 52 first-trimester examinations were evaluated. The mean gestational age was 8.9 ± 1.9 weeks. The mean duration of the sonographic examinations was 8.1± 1.4 minutes. During the examinations, there were 178 MI variations (mean ± SD, 0.9 ± 0.3) and 167 TI variations (mean ± SD, 0.2 ± 0.1). Conclusion. First-trimester sonographic examinations are associated with a negligible rise in TI. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007 [source] Effect of ketoprofen in topical formulation on vascular endothelial growth factor expression and tumor growth in nude mice with osteosarcomaJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2004Kenshi Sakayama Abstract OST cells, a low metastatic cell line established from human osteosarcoma, were inoculated under the periosteum of the ossa cranii of nude mice. Four weeks later, tumors were percutaneously treated for an additional 4 weeks with a patch containing either placebo or ketoprofen (KP). In the placebo group, OST cells formed osteoid and invaded the cranial bone. Tumor mass weighed 3.54 g. Approximately 85% of cells within the tumor expressed proliferating cell nuclear antigen (PCNA), indicating that they were proliferating with a high mitotic activity. Many feeder vessels were located within the tumor. The majority of tumor cells expressed intensely vascular endothelial growth factor (VEGF). In the KP group, invasion of OST cells into the cranial bone was suppressed and the tumor mass was 47% of that of the placebo group. Approximately 65% of cells within the tumor were PCNA-negative, indicating that their growth was arrested. There were considerably fewer feeder vessels within the tumor in the KP group than in the placebo group. Only a small number of cells expressed VEGF. Based on these findings, we concluded that topical administration of KP to nude mice with osteosarcoma inhibited VEGF expression, reduced the development of feeder vessels for supply of nutrients and oxygen, and suppressed tumor growth. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] Micro-focus X-ray computed tomography images of the 3D structure of the cranium of a fetus with asymmetric double malformationCONGENITAL ANOMALIES, Issue 1 2006Takashi Shibata ABSTRACT,, Reconstructed micro computed tomography (Micro-CT, µ-CT) images have revealed the detailed three-dimensional structure of the cranium of human fetal congenital anomalies for the first time. The objects were a head and a cervix of female autosite and a parasite consisting of only a head conjoined to the scapular region of the autosite of an asymmetric double malformation (asymmetric conjoined twins, heteropagus twinning) at a gestational age of 8 months. The cranium of the autosite was normal, but that of the parasite was characterized by otocephaly (agnathia, synotia, and monorhina) and almost all the cranial bones were of an abnormal shape. It is suggested that a part of occipital bone (the basioccipital and exoccipital bones), the vomer and cribriform plate were absent and this resulted in the fusion and overlapping of bilateral temporal and craniofacial bones that should have been adjacent to them. This resulted in a reformation and relocation of most of the cranial bones. Micro-CT is a useful tool to visualize the detailed bone structure which has not been clarified by the conventional dissection methods and other imaging technologies and is a powerful instrument for studying congenital anomalies. [source] Expression of the dlx gene family during formation of the cranial bones in the zebrafish (Danio rerio): Differential involvement in the visceral skeleton and braincaseDEVELOPMENTAL DYNAMICS, Issue 5 2006L. Verreijdt Abstract We have used dlx genes to test the hypothesis of a separate developmental program for dermal and cartilage bones within the neuro- and splanchnocranium by comparing expression patterns of all eight dlx genes during cranial bone formation in zebrafish from 1 day postfertilization (dPF) to 15 dPF. dlx genes are expressed in the visceral skeleton but not during the formation of dermal or cartilage bones of the braincase. The spatiotemporal expression pattern of all the members of the dlx gene family, support the view that dlx genes impart cellular identity to the different arches, required to make arch-specific dermal bones. Expression patterns seemingly associated with cartilage (perichondral) bones of the arches, in contrast, are probably related to ongoing differentiation of the underlying cartilage rather than with differentiation of perichondral bones themselves. Whether dlx genes originally functioned in the visceral skeleton only, and whether their involvement in the formation of neurocranial bones (as in mammals) is secondary, awaits clarification. Developmental Dynamics 235:1371,1389, 2006. © 2006 Wiley-Liss, Inc. [source] Induction of chondrogenesis in neural crest cells by mutant fibroblast growth factor receptorsDEVELOPMENTAL DYNAMICS, Issue 2 2002Anita Petiot Abstract Activating mutations in human fibroblast growth factor receptors (FGFR) result in a range of skeletal disorders, including craniosynostosis. Because the cranial bones are largely neural crest derived, the possibility arises that increased FGF signalling may predispose to premature/excessive skeletogenic differentiation in neural crest cells. To test this hypothesis, we expressed wild-type and mutant FGFRs in quail embryonic neural crest cells. Chondrogenesis was consistently induced when mutant FGFR1-K656E or FGFR2-C278F were electroporated in ovo into stage 8 quail premigratory neural crest, followed by in vitro culture without FGF2. Neural crest cells electroporated with wild-type FGFR1 or FGFR2 cDNAs exhibited no chondrogenic differentiation in culture. Cartilage differentiation was accompanied by expression of Sox9, Col2a1, and osteopontin. This closely resembled the response of nonelectroporated neural crest cells to FGF2 in vitro: 10 ng/ml induces chondrogenesis, Sox9, Col2a1, and osteopontin expression, whereas 1 ng/ml FGF2 enhances cell survival and Sox9 and Col2a1 expression, but never induces chondrogenesis or osteopontin expression. Transfection of neural crest cells with mutant FGFRs in vitro, after their emergence from the neural tube, in contrast, produced chondrogenesis at a very low frequency. Hence, mutant FGFRs can induce cartilage differentiation when electroporated into premigratory neural crest cells but this effect is drastically reduced if transfection is carried out after the onset of neural crest migration. © 2002 Wiley-Liss, Inc. [source] Examining criteria for identifying and differentiating fossil faunal assemblages accumulated by hyenas and hominins using extant hyenid accumulationsINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 1 2010B. F. Kuhn Abstract Numerous authors have put forth criteria for distinguishing between assemblages collected by hyenas and hominins. Of the seven most recognised criteria used to distinguish hyenid from hominin assemblages, it has recently been suggested that four be rejected and three retained. The four rejected criteria are: an excessive proportion of horns and horn cores in hyena accumulated assemblages; the absence of small, hard, compact bones; mortality profiles; and the ratio of cranial bones to postcranial bones. The three criteria previous researchers suggested be retained are: a carnivore MNI ratio of ,20%; an abundance of cylinder fragments; and hyena-inflicted damage upon the bones. In this examination of over 27,000 faunal remains associated with all three species of extant bone-collecting hyenids from four countries and two continents, six of the seven previously established criteria and reconsiderations of criteria have been evaluated. The results of the present study indicate that of the six criteria examined, none, as written, are indicative of hyenid activity on bone assemblages of unknown origin. Copyright © 2008 John Wiley & Sons, Ltd. [source] Congruence of individual cranial bone morphology and neutral molecular affinity patterns in modern humansAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2009Noreen 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] The type specimen (LB1) of Homo floresiensis did not have Laron SyndromeAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2009Dean Falk Abstract The type specimen (LB1) of Homo floresiensis has been hypothesized to be a pathological human afflicted with Laron Syndrome (LS), a type of primary growth hormone insensitivity (Hershkovitz et al.: Am J Phys Anthropol 134 [2007] 198,208). Comparing measurements, photographs and three-dimensional, computed-tomography reconstructions of LB1 with data and diagnoses from the literature on LS, we critically evaluate numerous skull and postcranial traits that Hershkovitz etal. identified as being shared by LB1 and patients with LS. The statements regarding most of these traits are new to the clinical literature and lack quantitative support. LB1 and patients with LS differ markedly in the size and shape of the cranium; thickness and pneumatization of cranial bones; morphology of the face, mandible, teeth, and chin; form of the shoulder, wrist, and pelvis; and general body proportions including relative foot size. Claims that patients with LS are similar to LB1 in displaying protracted scapulae, short clavicles, low degrees of humeral torsion, flaring ilia, and curved tibiae are not supported by data or corroborating images. Some points of similarity (e.g., femoral neck-shaft angle, femoral bicondylar angle, and estimated stature) can be found in other hominins, and cannot be considered diagnostic. From our review and analysis, we conclude that LB1 did not suffer from LS. Am J Phys Anthropol, 2009. © 2009 Wiley-Liss, Inc. [source] Primate remains from African crowned eagle (Stephanoaetus coronatus) nests in Ivory Coast's Tai Forest: Implications for primate predation and early hominid taphonomy in South AfricaAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2006W. Scott McGraw Abstract Understanding the initial processes of deposition can help with interpretations of fossil assemblages. Here we discuss the taphonomy of primate remains collected under 16 nests of African crowned eagles (Stephanoaetus coronatus) in the Tai Forest, Ivory Coast. From 1,200 bones collected, including 669 primate bones, we calculated minimum number of individuals (MNI), survivability profiles, and damage profiles using methods identical to those employed by Sanders et al. (2003 J. Hum. Evol. 44:87,105) in their analysis of bones from eagle nests in Uganda. Crowned eagles leave a consistent taphonomic signature on their prey remains; hence, results from our analysis of the Tai assemblage are similar to those from the Ugandan sample. Hindlimb and cranial bones are relatively abundant in the sample, while ribs, vertebrae, carpals, and tarsals do not survive well. Primate crania typically display puncture marks around the eye, long bones remain largely intact, and scapulae exhibit raked breakage. These data have implications for understanding the dynamic between extant primates and one of their principle predators, as well as the taphonomy of hominid-bearing caves in South Africa. We concur with Berger and Clarke (1995 J. Hum. Evol. 29:275,299) that a large raptor could have been responsible for the death of the Taung child, Australopithecus africanus. Am J Phys Anthropol 131:151,165, 2006. © 2006 Wiley-Liss, Inc. [source] | ||||||||||