The pathological and radiological hallmarks of multiple sclerosis (MS) include multiple demyelinated lesions disseminated throughout the white matter of the central nervous system (CNS). More recently, the cerebral cortex has been shown to be affected in MS, but the elucidation of events causing cortical demyelination has been hampered by the lack of animal models reflecting such human cortical pathology. In this report, we have described the presence of cortical gray matter and callosal white matter demyelinating lesions in the chronic experimental autoimmune encephalomyelitis (EAE) mouse model of MS. Similar to the pathological lesions of MS patients, EAE lesions have been classified as type I-leukocortical, type II-intracortical and type III-subpial. All of these lesions had varying degrees of demyelination, inflammatory cells and reactive astrocytes. Similar to MS, cortical layers during EAE showed demyelination, microglia activation, synaptic protein alterations and apoptotic cells. In addition, the callosal white matter during EAE had many inflammatory demyelinating lesions and axon degeneration. Functional electrophysiological conduction analysis showed deficits in both myelinated and unmyelinated callosal axons during early and late EAE. The chronic EAE mouse model has features that mimic cortical and callosal pathology of MS, and can be potentially used to screen agents to prevent these features of disease.

The legal environment is one factor that influences injection drug users' (IDUs) risk for HIV and other bloodborne pathogens such as hepatitis C virus (HCV). We examined the association between law enforcement encounters (i.e., arrests and citations) and receptive syringe sharing among IDUs in the context of an intensified policing effort. We conducted a mixed methods analysis of 30 qualitative and 187 quantitative interviews with IDUs accessing services at a Los Angeles, CA syringe exchange program from 2008 to 2009. Qualitative findings illustrate concerns related to visibility, drug withdrawal, and previous history of arrest/incarceration. In quantitative analysis, the number of citations received, current homelessness, and perceiving that being arrested would be a “big problem” were independently associated with recent syringe sharing. Findings illustrate some of the unintended public health consequences associated with intensified street-level policing, including risk for HIV and HCV transmission.

Sympatric species of coprophagus dung beetles rely on essentially the same resource for provisioning broods, which raises the question of how local species diversity is maintained. Interspecific competition may be mitigated to some extent by large-scale spatial (e.g., habitat type) and temporal (e.g., seasonal) variation in activity. Niche partitioning also occurs at the scale of individual dung pads. We examined the extent to which inter-and intraspecific variation in adult morphology and behavior contribute to spatial and temporal partitioning above and below the dung pad in the dung beetle community of Kibale Forest, Uganda. Excavations in the vicinity of dung pads revealed significant heterogeneity among species and guilds in the lateral distance between tunnels and dung, and in tunnel depth. Patterns of succession and diel activity demonstrated strong temporal dissociations among guilds. In one species, Onthophagus multicornis, we found a bimodal distribution of male horn sizes and a tunneling pattern consistent with alternative reproductive tactics.