Using metabolomics to dissect host-parasite interactions.

Protozoan parasites have evolved diverse growth and metabolic strategies for surviving and proliferating within different extracellular and intracellular niches in their mammalian hosts. Metabolomic approaches, including high coverage metabolite profiling and (13)C/(2)H-stable isotope labeling, are increasingly being used to identify parasite metabolic pathways that are important for survival and replication in vivo. These approaches are highlighting new links between parasite carbon metabolism and the ability of different parasite stages to colonize specific niches or host cell types. They have also revealed novel metabolic regulatory mechanisms that are important for homeostasis and survival in potentially nutrient variable environments. These studies highlight the importance of parasite and host metabolism as determinants of host-parasite interactions.

Firearm-related assaults on Los Angeles roadways.

During the summer of 1987, we investigated a series of firearm assaults occurring on Los Angeles County (California) roadways. Using law enforcement records, we identified 137 incidents of roadway assaults with firearms. Of these 137 incidents, 39% were brandishings and 61% were shootings. Of the shootings, 20% resulted in injuries; two were fatal. We compared the findings for June through August 1987 with findings for earlier years and found that the incidence rate of freeway firearm assault had increased each year from 1985 through 1987 for both freeway shootings and brandishings. We also found a positive association between freeway congestion and freeway firearm assaults in 1987.