Malignant brain tumors are among the most lethal of human tumors, with limited treatment options currently available. A complex array of recurrent genetic and epigenetic changes has been observed in gliomas that collectively result in derangements of common cell signaling pathways controlling cell survival, proliferation, and invasion. One important determinant of gene expression is DNA methylation status, and emerging studies have revealed the importance of a recently identified demethylation pathway involving 5-hydroxymethylcytosine (5hmC). Diminished levels of the modified base 5hmC is a uniform finding in glioma cell lines and patient samples, suggesting a common defect in epigenetic reprogramming. Within the tumor microenvironment, infiltrating immune cells increase oxidative DNA damage, likely promoting both genetic and epigenetic changes that occur during glioma evolution. In this environment, glioma cells are selected that utilize multiple metabolic changes, including changes in the metabolism of the amino acids glutamate, tryptophan, and arginine. Whereas altered metabolism can promote the destruction of normal tissues, glioma cells exploit these changes to promote tumor cell survival and to suppress adaptive immune responses. Further understanding of these metabolic changes could reveal new strategies that would selectively disadvantage tumor cells and redirect host antitumor responses toward eradication of these lethal tumors.

Dissection of a human cadaver is a time-honored tradition for teaching anatomy in medical education. However, in recent years, for a variety of reasons, including costs and ethical concerns, some medical programs have ceased cadaver dissection in exchange for virtual dissection of cadavers in cyberspace. Past research suggests that students find work on a cadaver to be distressing, but also rewarding. This study analyzed journal entries from 21 undergraduate students working with a cadaver in a gross anatomy course. An empirical, phenomenological analysis of the data identified 19 common themes among the participant's journal entries. In addition, the analysis disclosed how participants usually felt a need to justify the act of dissection. Finally, the analysis identified how students differed in the varied ways they coped with the ambiguous status of the cadaver, which was sometimes viewed as a deceased person while at other times experienced as a fascinating machine. Based on the findings, the researchers offer recommendations for helping students to better cope with the experience of cadaver dissection and to use the experience pedagogically to better prepare students for the stress of the medical world, especially issues surrounding death and dying.

The systematic implementation of a simulation curriculum in a neurosurgery training program is feasible, is favorably regarded, and has a positive impact on trainees of all levels, particularly in junior years. All simulation forms, cadaver, physical, and haptic/computerized, have a role in different stages of learning and should be considered in the development of an educational simulation program.

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The primary purpose of the present study is to obtain evidence as to the destination of the recently discovered unmyelinated primary afferent fibers in the mammalian dorsal funiculus. To do this rat dorsal roots were transected unilaterally from segments T8 or T9 caudally, and the numbers of axons were determined in the C3 fasciculus gracilis in normal animals and from both sides of the rhizotomied animals. In addition, C3 fasciculus gracilis counts were done in animals that had complete T6 or T10 spinal transections. The data indicate that there is an 80% loss of unmyelinated axons ipsilaterally and a 60% loss contralaterally in the fasciculus gracilis of the rhizotomied animals. These findings are interpreted as indicating that a significant fraction of the unmyelinated fibers in the fasciculus gracilis ascend, presumably to the nucleus gracilis in the brain stem, and also that a significant number of these fibers branch. We also provide evidence for contralateral myelinated primary afferent fiber projection in the fasciculus gracilis and show that the myelinated primary afferent fibers seem to be a more diverse population than the unmyelinated primary afferent fibers in the C3 fasciculus gracilis.