Murine macrophage activation by staphylococcal exotoxins.

We investigated the ability of staphylococcal enterotoxins A and B, exfoliative toxins A and B, and toxic shock syndrome toxin 1 to activate macrophages. All of the toxins tested had the potential to stimulate tumoricidal activity in peritoneal macrophages from lipopolysaccharide-responsive C3HeB/FeJ mice. In contrast, none of the toxins activated cytotoxicity in lipopolysaccharide-unresponsive macrophages from C3H/HeJ mice. We also studied toxin stimulation of monokine secretion. Staphylococcal enterotoxin A, toxic shock syndrome toxin 1, and both exfoliative toxins triggered C3HeB/FeJ macrophages to secrete tumor necrosis factor alpha, but enterotoxin B induced only marginal amounts of tumor necrosis factor. All of the toxins used stimulated interleukin-6 production by macrophages from both strains of mice. Nitric oxide is produced in response to the exfoliative toxins only by the lipopolysaccharide-responsive macrophages. These results suggest that macrophages respond differently to several staphylococcal exotoxins.     

The impact of the Texas 1989 motorcycle helmet law on total and head-related fatalities, severe injuries, and overall injuries.

The State of Texas implemented a mandatory total motorcycle helmet law for all operators and passengers, effective September 1, 1989. In this study the impact of this intervention on frequency of both total and head-related fatalities, severe injuries, and overall injuries for operators during the subsequent year was quantified. This quantification is important because 26 states in the United States fail to have strict, mandatory helmet laws. The Box-Tiao time-series intervention methodology is used to estimate secular trends before and changes after the implementation of the law, analyzing Department of Public Safety monthly injury accident data for a period of 6 years collected from traffic accident reports filed for each motorcycle injury accident. Trends in fatalities and injuries (except for head-related deaths) estimated before implementation of the law approximated the 9.4% average annual decline in motorcycle registrations. Additional declines of 12.6% and 57.0%, respectively, were estimated for total and head-related fatalities during the year after the law was implemented. Declines of 13.1% and 54.6% were estimated for severe injuries for total and head-related accidents. Declines of 12.3% and 52.9% were found for total and head-related injuries overall.     

Enhancing psychotherapy outcomes via providing feedback on client progress: a replication

Several systems have been developed to monitor and feedback information about a client's responses to psychotherapy as a method of enhancing client outcome. The current study divided 1020 clients into four groups (two experimental and two control) to determine if feedback regarding client progress, when provided to a therapist, affected client outcome and number of sessions attended. Results showed that feedback increased the duration of treatment and improved outcome for clients identified as potential treatment failures thereby replicating an earlier study using nearly identical methodology. Nearly twice as many clients in the feedback group achieved clinically significant or reliable change and fewer were classified as deteriorated by the time treatment ended. For those clients who were predicted to have a positive response to treatment, feedback to therapists resulted in an equal number of treatment sessions and equivalent outcomes compared to the no feedback controls. The results are discussed in terms of quality management in routine clinical practice and the need to base treatment decisions on clients' response to treatment rather than arbitrary session limits. Suggestions for additional research aimed at enhancing the effects of feedback on client outcome are made. Copyright © 2002 John Wiley & Sons, Ltd.     

Propyl gallate delays senescence in Drosophila melanogaster

The effect of propyl gallate (PGL) on life span in Drosophila was investigated. Four groups of flies were supplemented as follows: group 1, no PGL; group 2, no PGL supplement until 28 days followed by 0.3% PGL for remaining life span; group 3, 0.3% PGL from 7 days to 28 days, then none for remaining life span; and group 4, 0.3% PGL from 7 days until death. In all cases, PGL significantly increased mean life span. The largest increase in mean life span (34.2%) was in the group receiving PGL for the entire life span (group 4). Increases of 14.6% and 14.7% were measured in groups 2 and 3, respectively.     

Slow degeneration of zebrafish Rohon-Beard neurons during programmed cell death.

Rohon-Beard cells are large, mechanosensory neurons located in the dorsal spinal cord of anamniote vertebrates. In most species studied to date, these cells die during development. We followed labeled Rohon-Beard cells in living zebrafish embryos and found that they degenerate slowly, over many days. During degeneration, the soma shrinks and finally disappears, and the processes become beady in appearance and finally break apart, but they do not retract. Zebrafish Rohon-Beard cells apparently fragment their DNA, as revealed by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) labeling, before undergoing degenerative morphologic changes. We also followed the development of labeled dorsal root ganglion neurons, as they are developing at the same stages that Rohon-Beard cells are degenerating. We found that, although axons of both cell types extend into similar regions, Rohon-Beard cells degenerate normally in mutants lacking dorsal root ganglia, providing evidence that interactions between the two cell types are not responsible for Rohon-Beard cell degeneration. Developmental Dynamics 229:30-41,2004.     

Copper deficiency during parenteral nutrition: a report of four pediatric cases.

The standard of care for patients with cholestasis (direct bilirubin >or=2 mg/dL) while receiving parenteral nutrition (PN) solutions is to reduce or discontinue the copper and manganese. The repercussions of this action have not been studied. Two adult case reports document low serum copper levels associated with clinical symptoms of copper deficiency after the removal of copper from their PN solutions. We now describe the first known series of pediatric patients to develop copper deficiency after copper was removed from their PN solutions.     

Muscarinic M3 receptors are coupled to two signal transduction pathways in rat submandibular cells

The receptor subtypes involved in muscarinic-induced phosphoinositide hydrolysis and adenylate cyclase inhibition in rat submandibular acinar cells were characterized by comparing the inhibitory potencies of four muscarinic antagonists on the two signal transduction responses. Carbachol-induced phosphatidylinositol 4,5-bisphosphate (PIP2) hydrolysis was inhibited by all antagonists with a potency rank order of 4-diphenylacetoxy-N-methyl piperidine methobromide (4-DAMP) = atropine much greater than pirenzepine much greater than AF-DX 116 (P less than 0.01). The same rank order was observed in antagonist-reversal of the reduction of cAMP caused by carbachol in the model. These findings suggest that muscarinic effects are mediated by M3 receptors in both the phosphoinositide and adenylate cyclase pathways in the submandibular gland.