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Background: Failure of palatal shelf fusion at the precise gestational time point when shelf elevation and migration normally occur results in clefting. The present study defined the mechanism of clefting in the congenital caprine model by evaluating the temporal sequence of palatal shelf fusion. Methods: Six Spanish-type goats pregnant with twins were gavaged for 10 days (gestational days 32 to 41) with anabasine. Goats were examined with ultrasound throughout this period to assess fetal movement and evaluated histologically. Twelve untreated, unclefted fetuses served as controls. Results: After anabasine induction, real-time ultrasound confirmed a dramatic decrease in fetal movement. Hyperflexion of the neck occurred throughout the experimental period compared with control fetuses, in which spontaneous neck movements occurred. Histologic evaluation of the induced fetuses demonstrated the tongue wedged between the palatal shelves throughout the period of fusion. The shelves remained vertically oriented without elevation, ultimately resulting in clefting. The unclefted, control group demonstrated progressive elevation and migration of the palatal shelves between gestational days 38 and 40, with contact and fusion of the medial edge epithelia in the midline. Conclusions: Palatal clefting in the congenital caprine model occurred concomitant with reduced fetal movement. Resultant neck hyperflexion causes the tongue to obstruct medial migration of the palatal shelves and fusion, whereas the shelves themselves are either directly prevented from elevation secondary to anabasine impairment or indirectly secondary to the obstructing tongue. Although the molecular mechanism for the teratogenic effects of anabasine remains elusive, the authors have demonstrated an association between reduced fetal movement and palatal clefting in their congenital caprine model.

The key to achieving an excellent result following rhinoplasty lies in a strong fundamental knowledge of nasal anatomy. The purpose of this study was to analyze the anatomic and histologic relationship of the nose to the alar-facial crease. Fifteen cadaver noses were dissected and a total of thirty lower lateral cartilages were measured. Two fresh cadaver noses were fixed in neutral buffer formalin and embedded in paraffin. They were then sectioned into 6-mu coronal and sagittal sections and stained with hematoxylin and eosin, Eosin von Geison, and safranin to evaluate for collagen, elastin and muscle, respectively. Measurements of the lower lateral cartilages showed the average lateral crural height was 23.5 mm (+/- 2.5 mm), lateral crus width was 11.7 mm (+/- 1.5 mm), lateral domal width was 5.7 mm (+/- 0.9 mm), and intercrural distance was 20.2 mm (+/- 3.2 mm). No statistical differences were noted between male and female cadaver measurements. Histologic sections showed the area of the alar-facial crease to have a greater quantity of elastin fibers compared with muscle, collagen, or cartilage. These elastin fibers were predominantly orientated vertically (anterior-posterior) rather than horizontally (cephalo-caudad). This study demonstrates a higher ratio of elastin to collagen fibers in the region of the alar-facial crease.

Purpose: To assess long-term results and complications of cancellous bone graft taken from the distal radius. Methods: A total of 1,670 cases of bone graft taken from the distal radius for various indications were reviewed retrospectively. The patients were evaluated for success of bone grafting and for the following complications: fracture through donor site, local infection, DeQuervain's tenosynovitis, and neuroma of the superficial radial nerve. Results: The overall complication rate including bone graft failure within a mean follow-up period of 4.5 years was 4%. Bone graft failure required regrafting with iliac bone in 38 patients (2.3%). DeQuervain's tenosynovitis was noted in 21 patients (1.3%), local soft-tissue infection was noted in 3 patients (0.2)%, fracture through donor site was noted in 2 patients (0.1%), and superficial radial nerve neuromas were noted in 2 patients (0.1%). There were no cases of osteomyelitis. Conclusions: Bone grafting from the distal radius is effective with minimal complications and is a practical adjunct to reconstructive hand procedures.

Poly(urethane-imide)s (PUI)s were prepared by the intermolecular Diels-Alder (DA)reaction of 4-methyl-1,3-phenylene-bis(2-furanylmethylthioethylcarbamate) (MPFTC) with various bismaleimides. The DA reaction was carried out in 1,4-dioxane as a solvent as well as in bulk, followed by aromatization of tetrahydrophthalimide intermediates in the presence of acetic anhydride. All the polymers were characterized by elemental analysis, IR spectral studies and thermogravimetry. The PUIs exhibit moderate thermal stability. MPFTC and bismaleimides were polymerized (at 145 - 10°C) by an "in situ" DA intermolecular reaction into moderately thermally stable PUIs glass-fiber composite (i.e., laminates) and were characterized by their chemical resistance and mechanical properties.

The human ear is a defining feature of the face. Its subtle structures convey signs of age and sex that are unmistakable yet not easily defined. With analysis of normative cross-sectional data, this study explored anatomic and aesthetic differences in the ear between men and women, as well as changes in ear morphology with age. A total of 123 volunteers were randomly selected for this study. The cohort consisted of 89 women ages 19 to 65 years (median age, 42 years) and 34 men ages 18 to 61 years (median age, 35 years). The average total ear height across the entire cohort for both left and right ears was 6.30 cm, average lobular height was 1.88 cm, and average lobular width was 1.96 cm. As expected based on head size, significant sex-related differences were noted in the distance from the lateral palpebral commissure to both the helical root and insertion of the lobule. Measured distances in both vectors were approximately 4.6 percent longer in men than in women. Similarly, the height of the pinna was significantly larger in men than in women by approximately 6.5 percent. The average height and width of the lobule, however, were nearly identical in men and women. Analysis of age-related data showed a significant difference in the total ear height between the subpopulations; however, this difference was not significant after the lobular height was subtracted from total ear height, suggesting that the lobule was the only ear structure that changed significantly with age. In addition, lobular width decreased significantly with age. This study establishes normative data for ear morphology and clearly demonstrates the changes in earlobe morphology that occur with advancing age.