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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2009.11.021 Byline: Heather L. Szabo-Rogers, Lucy E. Smithers, Wardati Yakob, Karen J. Liu Keywords: Craniofacial; Morphogenesis; Frontonasal; Neural crest; Endoderm; Cilia; Cranial base; Shh; Proliferation Abstract: The vertebrate head is an extremely complicated structure: development of the head requires tissue-tissue interactions between derivates of all the germ layers and coordinated morphogenetic movements in three dimensions. In this review, we highlight a number of recent embryological studies, using chicken, frog, zebrafish and mouse, which have identified crucial signaling centers in the embryonic face. These studies demonstrate how small variations in growth factor signaling can lead to a diversity of phenotypic outcomes. We also discuss novel genetic studies, in human, mouse and zebrafish, which describe cell biological mechanisms fundamental to the growth and morphogenesis of the craniofacial skeleton. Together, these findings underscore the complex interactions leading to species-specific morphology. These and future studies will improve our understanding of the genetic and environmental influences underlying human craniofacial anomalies. Author Affiliation: Department of Craniofacial Development, King's College London, UK SE1 9RT Article History: Received 14 August 2009; Revised 29 October 2009; Accepted 17 November 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2008.03.027 Byline: Heather L. Szabo-Rogers, Poongodi Geetha-Loganathan, Suresh Nimmagadda, Kathy K. Fu, Joy M. Richman Keywords: Chicken embryo; FGF receptor; Cleft lip; Frontonasal mass; Craniofacial; SU5402; FGF2; Foil; SPROUTY; MSX; PYST1; BMP4 Abstract: Fibroblast growth factors (FGFs) are required for brain, pharyngeal arch, suture and neural crest cell development and mutations in the FGF receptors have been linked to human craniofacial malformations. To study the functions of FGF during facial morphogenesis we locally perturb FGF signalling in the avian facial prominences with FGFR antagonists, foil barriers and FGF2 protein. We tested 4 positions with antagonist-soaked beads but only one of these induced a facial defect. Embryos treated in the lateral frontonasal mass, adjacent to the nasal slit developed cleft beaks. The main mechanisms were a block in proliferation and an increase in apoptosis in those areas that were most dependent on FGF signaling. We inserted foil barriers with the goal of blocking diffusion of FGF ligands out of the lateral edge of the frontonasal mass. The barriers induced an upregulation of the FGF target gene, SPRY2 compared to the control side. Moreover, these changes in expression were associated with deletions of the lateral edge of the premaxillary bone. To determine whether we could replicate the effects of the foil by increasing FGF levels, beads soaked in FGF2 were placed into the lateral edge of the frontonasal mass. There was a significant increase in proliferation and an expansion of the frontonasal mass but the skeletal defects were minor and not the same as those produced by the foil. Instead it is more likely that the foil repressed FGF signaling perhaps mediated by the increase in SPRY2 expression. In summary, we have found that the nasal slit is a source of FGF signals and the function of FGF is to stimulate proliferation in the cranial frontonasal mass. The FGF independent regions correlate with those previously determined to be dependent on BMP signaling. We propose a new model whereby, FGF-dependent microenvironments exist in the cranial frontonasal mass and caudal maxillary prominence and these flank BMP-dependent regions. Coordination of the proliferation in these regions leads ultimately to normal facial morphogenesis. Author Affiliation: Department of Oral Health Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver BC, Canada V6T 1Z3 Article History: Received 14 November 2007; Revised 22 February 2008; Accepted 17 March 2008

In practice the secondary prevention of work-related upper extremity (WRUE) symptoms generally targets biomechanical risk factors. Psychosocial risk factors have also been shown to play an important role in the development of WRUE symptom severity and future disability. The addition of a stress management component to biomechanically focused interventions may result in greater improvements in WRUE symptoms and functional limitations than intervening in the biomechanical risk factors alone. Seventy office workers with WRUE symptoms were randomly assigned to an ergonomics intervention group (assessment and modification of work station and stretching exercises) or a combined ergonomic and job stress intervention group (ergonomic intervention plus two 1-h workshops on the identification and management of workplace stress). Baseline, 3- and 12-month follow-up measures of observed ergonomic risks and self-reported ergonomic risks, job stress, pain, symptoms, functional limitation, and general physical and mental health were obtained from all participants. While both groups experienced significant decreases in pain, symptoms, and functional limitation from baseline to three months with improvements continuing to 12 months post baseline, no significant differences between groups were observed for any outcome measures. Findings indicate that the additional two-session job stress management component did not significantly enhance the short- or long-term improvements brought about by the ergonomic intervention alone. Keywords: Ergonomic intervention; Stress management; Upper extremity symptoms; Function

Technical writers have clear steps to follow when creating a video on a technical subject. The first step is cost consideration. Management steps follow for choosing group members and making a production schedule. The script writing uses established principles of screenwriting. Casting and location selection complete the pre-production steps. Production involves the actual shooting on location. Post-production steps include editing, distribution and packaging. Other considerations involve live presentations and use of in-house resources.