Arc-like curvilinear bullet pathways along inner surface of skull - two cases.

To provide example cases within the peer-reviewed literature of a phenomenon related to certain gunshot wounds of the head where the bullet pathway courses along the inner table of the skull. Presentation of two cases discovered at medicolegal autopsy. The two cases provide radiologic and autopsy demonstration of bullet pathways within the head where the projectiles track along the inner aspect of the cranium, in a circumferential manner, such that the bullets are recovered in a location on the opposite side of the brain/head, with no projectile pathway within the intervening deep structures of the brain. The cases provide photographic and radiologic autopsy documentation of the phenomenon, which is described in forensic pathology textbooks and rare peer-reviewed literature sources, but without photographic demonstration. Recognition of this phenomenon in the clinical setting, or when correlating autopsy external and radiologic findings with historical information, may provide an explanation for situations where immediate incapacitation does not occur following a gunshot wound of the head.

Differential regulation of nucleus accumbens glutamate and GABA in obesity-prone and obesity-resistant rats.

Obesity is one of the leading health concerns in the United States. Studies from human and rodent models suggest that inherent differences in the function of brain motivation centers, including the nucleus accumbens (NAc), contribute to overeating and thus obesity. For example, there are basal enhancements in the excitability of NAc GABAergic medium spiny neurons (MSN) and reductions in basal expression of AMPA-type glutamate receptors in obesity-prone vs obesity-resistant rats. However, very little is known about the regulation of extracellular glutamate and GABA within the NAc of these models. Here we gave obesity-prone and obesity-resistant rats stable isotope-labeled glucose (13 C6 -glucose) and used liquid chromatography mass spectrometry (LC-MS) analysis of NAc dialysate to examine the real-time incorporation of 13 C6 -glucose into glutamate, glutamine, and GABA. This novel approach allowed us to identify differences in glucose utilization for neurotransmitter production between these selectively bred lines. We found that voluntarily ingested or gastrically infused 13 C6 -glucose rapidly enters the NAc and is incorporated into 13 C2 -glutamine, 13 C2 -glutamate, and 13 C2 -GABA in both groups within minutes. However, the magnitude of increases in NAc 13 C2 -glutamine and 13 C2 -GABA were lower in obesity-prone than in obesity-resistant rats, while basal levels of glutamate were elevated. This suggested that there may be differences in the astrocytic regulation of these analytes. Thus, we next examined NAc glutamine synthetase, GAD67, and GLT-1 protein expression. Consistent with reduced 13 C2 -glutamine and 13 C2 -GABA, NAc glutamine synthetase and GLT-1 protein expression were reduced in obesity-prone vs obesity-resistant groups. Taken together, these data show that NAc glucose utilization differs dramatically between obesity-prone and obesity-resistant rats, favoring glutamate over GABA production in obesity-prone rats and that reductions in NAc astrocytic recycling of glutamate contribute to these differences. These data are discussed in light of established differences in NAc function between these models and the role of the NAc in feeding behavior.

Myositis ossificans of the breast - A rare case report with radiologic-pathologic correlation.

Myositis ossificans is a pathologic process of ossification in soft tissues. The breast is an exceptionally rare location for myositis ossificans with less than 5 cases documented in the English literature. We present a case of a 66-year-old woman with myositis ossificans of the left breast and no known initiating trauma. The significance of the progression of clinical and radiological findings are discussed in detail. This case shows the importance of radiology for identifying unique pathology as well as close radiological follow up.