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Research reveals heat shock induced heat shock regulons, including those controlled by the sigma (sup)B regulon, along with many operons not reported to be heat inducible in Bacillus subtilis. Among the new operons those of arginine biosynthesis and transport and some additional members of the sigma (sup)B regulon are prominent.

Research has been conducted on Bacillus subtilis transcriptional responses to peroxide stress. The study of these responses has been carried out via gene expression monitoring in stressed cells using DNA microarrays is presented.

Drug seeking and the vulnerability to relapse occur when individuals are exposed to an environment with sensory cues in which drug taking has occurred. Memory formation is thought to require plasticity in synaptic circuits, and so we examined whether the memory for a drug-paired environment correlates with changes in the synaptic circuits of the basolateral amygdala (BLA), in which emotional learning is a recognized phenomenon. We used amphetamine(AMPH)as the unconditioned stimulus in the conditioned place preference (CPP) paradigm. Rats were conditioned with 1.0 mg/kg AMPH and tested, drug free, 72 h after the last conditioning session. Controls included a saline-conditioned group and a home cage AMPH injection group, whose exposure to the CPP apparatus was delayed by 4 h, long enough to clear the AMPH from the brain. We counted excitatory synapses in the BLA using the electron microscope and the physical disector design (stereology). Rats that expressed AMPH CPP had an increase in excitatory synapses compared with controls. Excitatory synaptic activity was measured using in vivo intracellular recordings from the BLA in anesthetized rats. We found that AMPH CPP, but not drug alone, increased measures of synaptic drive, including the frequency of synaptic events, and the paired-pulse ratio of synaptic inputs to BLA pyramidal neurons. The in vivo findings suggest that the increase in BLA neuronal excitatory drive reflects the change in excitatory synapse number. Thus, context- drug associations are accompanied by structural and functional plasticity in the BLA, findings that have important implications for drug-seeking behavior. [ABSTRACT FROM AUTHOR]

Psychostimulant drug experience leads not only to long-lasting changes in behavior but also modifications in the activity and morphology of pyramidal neurons in the medial prefrontal cortex (mPFC). The objective of this study was to establish whether repeated treatment of rats with amphetamine (AMPH) is accompanied by changes in the pattern or types of synapses in the mPFC and, specifically, onto neurons that project to the lateral hypothalamus, where our earlier work has shown increased markers of neuronal activity after repeated AMPH treatment (Morshedi and Meredith [] Psychopharmacology (Berl) 197:179-189). Rats were treated with a behaviorally sensitizing regimen of AMPH, following which synapses in the infralimbic and prelimbic cortices of the mPFC, were analyzed with unbiased stereology (physical disector and electron microscopy). All synapses were counted and their targets were identified by standard methodological criteria. Repeated AMPH administration was associated with a significant increase in the number of asymmetric axospinous synapses, no change in axodendritic or axosomatic contacts, and no change in the total number of synapses on corticolateral hypothalamic pyramidal neurons compared to vehicle-treated rats. Therefore, behavioral sensitization as a result of repeated exposure to AMPH is accompanied by the increased formation of spine, but not dendritic, synapses onto pyramidal neurons in the mPFC. Synapse 63:126-135, 2009. ©2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to describe the technique for evaluating hepatic arterial blood pressure changes during lobar chemoembolization using antireflux devices. Intraprocedural femoral and hepatic arterial blood pressures were measured and chemoembolization terminated when significant reduction in the difference occurred. Liver toxicity was evaluated. Eleven patients underwent 24 lobar chemoembolization procedures. Early termination of delivery occurred in 11 of 24 (46%) procedures in which the mean relative reduction in systemic-hepatic arterial pressure differential was 48%. The mean liver toxicity score was 1.2. This compares to delivery of the entire dose in 13 of 24 (54%) procedures in which the mean relative reduction in systemic-hepatic arterial pressure differential was 12% with a mean liver toxicity score of 1.2., Conclusion: When antireflux devices are used, intraprocedural assessment of hepatic artery blood pressure changes may be a useful embolization safety endpoint.