Distinct patterns of ΔFosB induction in brain by drugs of abuse

The transcription factor ΔFosB accumulates and persists in brain in response to chronic stimulation. This accumulation after chronic exposure to drugs of abuse has been demonstrated previously by Western blot most dramatically in striatal regions, including dorsal striatum (caudate/putamen) and nucleus accumbens. In the present study, we used immunohistochemistry to define with greater anatomical precision the induction of ΔFosB throughout the rodent brain after chronic drug treatment. We also extended previous research involving cocaine, morphine, and nicotine to two additional drugs of abuse, ethanol and Δ9-tetrahydrocannabinol (Δ9-THC, the active ingredient in marijuana). We show here that chronic, but not acute, administration of each of four drugs of abuse, cocaine, morphine, ethanol, and Δ9-THC, robustly induces ΔFosB in nucleus accumbens, although different patterns in the core vs. shell subregions of this nucleus were apparent for the different drugs. The drugs also differed in their degree of ΔFosB induction in dorsal striatum. In addition, all four drugs induced ΔFosB in prefrontal cortex, with the greatest effects observed with cocaine and ethanol, and all of the drugs induced ΔFosB to a small extent in amygdala. Furthermore, all drugs induced ΔFosB in the hippocampus, and, with the exception of ethanol, most of this induction was seen in the dentate. Lower levels of ΔFosB induction were seen in other brain areas in response to a particular drug treatment. These findings provide further evidence that induction of ΔFosB in nucleus accumbens is a common action of virtually all drugs of abuse and that, beyond nucleus accumbens, each drug induces ΔFosB in a region-specific manner in brain

Recent trends in the use of radical prostatectomy in England: the epidemiology of diffusion

OBJECTIVE To describe recent trends in the use of radical prostatectomy (RP) in England, as there is currently no consensus on the most effective treatment for localized prostate cancer, although RP is the treatment of choice among urological surgeons for men aged < 70 years. METHODS Routine data were assessed to establish the number of RPs performed in England in 1991–99. Age-standardized operation rates were compared by region and socio-economic group, and the geographical spread of use mapped. RESULTS The number of RPs performed annually increased nearly 20-fold between 1991 and 1999. Rates of surgery were greatest in the London National Health Service (NHS) regions and lowest in the Trent region. Outside London, the risk of surgery in a NHS hospital was significantly greater for men living in the least deprived areas; in London this trend was reversed. CONCLUSION Rapid increases in the use of RP showed marked regional variations, most likely related to access to prostate-specific antigen testing and the location of surgeons able to carry out radical surgery. By 1999, a third of procedures were still being undertaken in 'low-volume' hospitals, with implications for the quality of care and outcomes. Crucially, these developments occurred in the absence of robust information about the effectiveness of RP. Recent funding of a randomized trial of treatment options in this area is welcome, but wider questions remain about the timing of the evaluation of surgical technologies