There is increased tongue volume and deposition of fat at the base of tongue in apneics compared to controls. Increased tongue fat may begin to explain the relationship between obesity and obstructive sleep apnea.

We are interested in the controlled assembly of photoelectronic materials using peptides as scaffolds and porphyrins as the conducting material. We describe the integration of a peptide-based polymer strategy with the ability of designed basic peptides to bind anionic porphyrins in order to create regulated photoelectronically active biomaterials. We have described our peptide system in earlier work, which demonstrates the ability of a peptide to form filamentous materials made up of self-assembling coiled-coil structures. We have modified this peptide system to include lysine residues appropriately positioned to specifically bind meso-tetrakis(4-sulfonatophenyl)porphine (TPPS(4)), a porphyrin that contains four negatively charged sulfonate groups at neutral pH. We measure the binding of TPPS(4) to our peptide using UV--visible and fluorescence spectroscopies to follow the porphyrin signature. We determine the concomitant acquisition of helical secondary structure in the peptide upon TPPS(4) binding using circular dichroism spectropolarimetry. This binding fosters polymerization of the peptide, as shown by absorbance extinction effects in the peptide CD spectra. The morphologies of the peptide/porphyrin complexes, as imaged by atomic force microscopy, are consistent with the coiled-coil polymers that we had characterized earlier, except that the heights are slightly higher, consistent with porphyrin binding. Evidence for exciton coupling in the copolymers is shown by red-shifting in the UV--visible data, however, the coupling is weak based on a lack of fluorescence quenching in fluorescence experiments.

Rationale: The metabolic activity of the tongue is unknown in patients with obstructive sleep apnea (OSA). Tongue electromyographic (EMG) activity is increased in patients with OSA. This increase in tongue EMG activity is thought to be related to either increased neuromuscular compensation or denervation with subsequent reinnervation of the muscle fibers. Increased glucose uptake in the tongue would support increased neuromuscular compensation, whereas decreased glucose uptake in the tongue would support denervation with subsequent reinnervation of the muscle fibers.Objectives: To investigate the metabolic activity of the genioglossus and control upper airway muscles in obese patients with sleep apnea compared with obese control subjects.Methods: Obese subjects with and without OSA underwent a standard overnight sleep study to determine an apnea-hypopnea index. Each subject had a positron emission tomography with [ 18 F]-2-fluoro-2-deoxy-D-glucose scan in addition to noncontrast computed tomography or magnetic resonance imaging. Glucose uptake was quantified within upper airway tissues with the standardized uptake value.Measurements and Main Results: We recruited 30 obese control subjects (apnea-hypopnea index, 4.7 6 3.1 events per hour) and 72 obese patients with sleep apnea (apnea-hypopnea index, 43.5 6 28.0 events per hour). Independent of age, body mass index, sex, and race, patients with OSA had significantly reduced glucose uptake in the genioglossus (P = 0.03) in comparison with obese normal subjects. No differences in standardized uptake value were found in the control muscles (masseter [P = 0.38] and pterygoid [P = 0.70]) and subcutaneous fat deposits (neck [P = 0.44] and submental [P = 0.95]) between patients with OSA and control subjects.Conclusions: There was significantly reduced glucose uptake in the genioglossus of patients with sleep apnea in comparison with obese normal subjects with [18 F]-2-fluoro-2-deoxy-D-glucose positron emission tomography imaging. The reduction in glucose uptake was likely secondary to alterations in tongue muscle fiber-type or secondary to chronic denervation. The reduced glucose uptake argues against the neuromuscular compensation hypothesis explaining the increase in tongue EMG activity in obese patients with OSA.

CRTT continues to be a significant contributor to the morbidity and mortality of those injured during OEF and OIF. The distinct injury patterns and atypical imaging manifestations of blunt trauma and blast lung injury are important to recognize early because of the acuity of this patient population and the influence of accurate diagnosis on clinical management.

Combat-related thoracic trauma continues to be a significant contributor to the morbidity and mortality of those injured during OEF and OIF. This review of the imaging manifestations of penetrating thoracic injury during OEF and OIF focuses on key diagnostic findings for clinicians caring for combat casualties. The distinct injury pattern and atypical imaging manifestations of penetrating trauma are important to recognize early due to the acuity of this patient population and the influence of accurate diagnosis on clinical management.

Early identification of congenital heart diseases, specifically those affecting the structural integrity and function of the interventricular septum, in childhood is important toward decreasing the morbidity and mortality of those affected. We review the pertinent clinical and imaging manifestations for those with ventricular septal defects, ventricular septal aneurysms, tetralogy of Fallot, and hypertrophic (obstructive) cardiomyopathy, in addition to discussing first-line imaging studies, including echocardiography, and indications for advanced imaging.

IntroductionEnlarged upper airway soft tissues have been shown to be strong risk factors for the development of obstructive sleep apnea (OSA). Myopathic studies of the genioglossus and soft palate showed that apneics have an increased percentage of type II (fast twitch) muscle fibers and these fibers, in contrast to type I (slow twitch) fibers, have less overall glucose uptake and phosphorylation (Bottinelli et al., 2000). Positron emission tomography (PET) with [18F]-2-fluoro-2-deoxy-D-glucose (FDG) offers the unique ability to map glucose metabolism in region-specific tissues. We hypothesized that glucose metabolism would be decreased in the genioglossus and soft palate of apneics in comparison to controls.

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