Intraoperative ketamine reduces opiate consumption in the 48-h postoperative period in opiate-dependent patients with chronic pain. Ketamine may also reduce opioid consumption and pain intensity throughout the postoperative period in this patient population. This benefit is without an increase in side effects.

No abstract

Use of an EHR-based CTA led to significant increases in physicians' participation in and recruitment rates to an ongoing clinical trial. Given the trend toward the EHR implementation in health care centers engaged in clinical research, this approach may represent a much-needed solution to the common problem of inadequate trial recruitment.

Addition of putrescine of spermidine prevents the increase in ornithine decarboxylase activity in cultures of 3T3 cells brought about by pituitary growth factors and results in a rapid, specific, and reversible reduction of enzyme activity in cultures previously stimulated by the growth factors. These effects are not due to polyamine toxicity and do not require other organic medium components. The amines apparently share a single carrier-mediated transport system in 3T3 cells. Methylglyoxal bis(guanylhydrazone), an inhibitor of spermidine synthesis from putrescine was found to also inhibit uptake of each amine. Studies with this drug indicate that each amine is effective without further metabolism. Since ornithine decarboxylase activity decays more rapidly in the presence of each polyamine after addition of camptothecin, the major locus of amine action appears to be in the cytoplasm. However, direct inhibition of the enzyme in vivo by assimilated amines appears to account for at most a small part of the reduction in activity, a conclusion supported by the inability to recover activity in vitro. Also, neither amine seems to act by accelerating enzyme inactivation. When amines are removed from the medium, the subsequent recovery of enzyme activity is totally prevented by trichodermin, an inhibitor of protein synthesis, but is only slightly reduced by camptothecin. It is suggested that both putrescine and spermidine reduce ornithine decarboxylase activity by selectively inhibiting translation.

We conducted field and stream microcosm experiments to assess population-level (density, size distribution) and community-level (species richness metrics, multivariate analysis of community composition) responses of macroinvertebrates to heavy metals in the Arkansas River, a mining-polluted stream in Colorado, USA. Experiments were conducted in spring and summer to coincide with early and late developmental stages (i.e., instars) of the mayfly Rhithrogena hageni. Results of field experiments showed significant mortality at metal-contaminated sites during summer when mayfly populations were dominated by small, early instars (mean dry wt = 0.13 mg). In contrast, no significant mortality was observed in spring when organisms were larger (mean dry wt = 1.78 mg). Multivariate analyses based on abundance of dominant taxa clearly separated reference and metal-impacted stations in summer experiments but showed little separation in spring. We observed no significant effects of metals on species richness, number of mayfly species, or EPT (species richness of Ephemeroptera, Plecoptera, and Trichoptera) in.either field experiment. Using stream microcosms, we established concentration-response relationships between heavy metals and R. hageni density, species richness, mayfly richness, and EPT. Density of R. hageni was generally more sensitive to metals than measures of species richness, and summer populations of R. hageni were more sensitive to metals than spring populations. Because the presence of large, relatively tolerant individuals in spring coincided with periods of higher metal concentrations, R. hageni was protected from toxic effects in this system. We conclude that phenology and developmental stage are important factors influencing responses of some aquatic macroinvertebrates to metals. Thus, timing bioassessments to coincide with the presence of these sensitive life stages can improve our ability to detect subtle contaminant effects.