The association of serum anticholinergic activity with delirium in elderly medical patients

To investigate the hypothesis that elevated serum anticholinergic activity is independently associated with delirium in ill elderly persons, the authors performed a cross-sectional study of 67 acutely ill older medical inpatients. The presence of delirium was evaluated with the Confusion Assessment Method, and the presence of many delirium symptoms was measured by the Delirium Symptom Interview. Demographic data and clinical characteristics that may be important for the development of delirium were also collected. Logistic regression techniques demonstrated that elevated serum anticholinergic activity was independently associated with delirium. Among the subjects with delirium, a greater number of delirium symptoms was associated with higher serum anticholinergic activity.

Cytokine production in patients with anorexia nervosa, bulimia nervosa, and obesity

OBJECTIVE

We previously reported elevated serum levels of the cytokines interleukin-6 (IL-6) and transforming growth factor-beta (TGF-beta) in patients with anorexia nervosa (AN). We investigated the cellular production of these two cytokines and of interferon-gamma (IFN-gamma), interleukin-1alpha (IL-1alpha), and tumor necrosis factor-alpha (TNF-alpha) in subjects with AN, bulimia nervosa (BN), and obesity as well as in normal-weight control subjects.

METHODS

Supernatant fluids from isolated peripheral blood mononuclear cells (PBMC) incubated with and without concanavalin A (ConA) were assayed for cytokine concentrations by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Significant differences across the four groups were found in the stimulated cellular production of IFN-gamma and IL-6. Stimulated IFN-gamma production was elevated in the AN group compared to controls. IL-6 production was significantly elevated in obese subjects relative to the two normal-weight groups, BN and controls, and tended to be higher in the AN group than in the controls, but not significantly so. IL-1alpha production was greater in obese subjects.

CONCLUSION

The findings of increased IFN-gamma production and a tendency toward increased IL-6 production (both of which suppress food intake in animals) in individuals who severely restrict food intake suggest a potential role for these cytokines in the pathogenesis of AN. Elevated IL-6 and IL-1alpha production by PBMC in obese individuals requires further investigation to determine if these cytokines contribute to the development or perpetuation of obesity.

Serum anticholinergic activity and behavior following atropine sulfate administration in the rat

Anticholinergic agents such as atropine and scopolamine have long been suggested to produce delirium-like states in humans and experimental animals. Evidence for an anticholinergic mechanism in the pathogenesis of human delirium has accumulated, leading to studies of the behavioral effects of the anticholinergic drug atropine in animals. The current study addresses the adequacy of animal models of delirium in terms of sensitivity, specificity and pharmacological relevance. A multiple fixed-ratio fixed-interval reinforcement schedule was used to test the effects of relatively low doses of atropine on behavior in rats. Additionally, total serum anticholinergic activity (SAA) was measured under dose and time course conditions identical to those used in the behavioral study. Atropine reduced high and low rates of responding in a dose-dependent manner, and SAA increased in a dose dependent manner. SAA at atropine doses of 0.1 mg/kg to 1.0 mg/kg was similar to that found in delirious humans. These behavioral and serum level data suggest that relatively low doses of atropine, substantially below those used in previous attempts to model delirium using rats, may be more pharmacologically relevant to delirium and may minimize non-specific peripheral effects of this drug.

Effectiveness of liquid soap vs. chlorhexidine gluconate for the removal of Clostridium difficile from bare hands and gloved hands

OBJECTIVE

To compare liquid soap versus 4% chlorhexidine gluconate in 4% alcohol for the decontamination of bare or gloved hands inoculated with an epidemic strain of Clostridium difficile.

DESIGN

C difficile (6.7 log10 colony-forming units [CFU], 47% spores), was seeded onto bare or latex gloved hands of ten volunteers and allowed to dry. Half the volunteers initially washed with soap and half with chlorhexidine, followed by the other agent 1 week later. Cultures were done with Rodac plates at three sites on the hand: finger/thumbtips, the palmar surfaces of the fingers, and the palm. Statistical comparison was by paired Student's t test.

RESULTS

On bare hands, soap and chlorhexidine did not differ in residual bacterial counts on the finger/thumbtips (log10 CFU, 2.0 and 2.1, P = NS) and fingers (log10 CFU, 2.4 and 2.5, P = NS). Counts were too high on bare palms to quantitate. On gloved hands, soap was more effective than chlorhexidine on fingers (log10 CFU 1.3 and 1.7, P < .01) and palms (log10 CFU 1.5 and 2.0, P < .01), but not finger/thumbtips (log10 CFU 1.6 with each, P = NS). Residual C difficile counts were lower on gloved hands than bare hands (P < 0.01 to < 0.0001).

CONCLUSIONS

The two agents did not differ significantly in residual counts of C difficile on bare hands, but on gloved hands residual counts were lower following soap wash than following chlorhexidine wash. These observations support the use of either soap or chlorhexidine as a handwash for removal of C difficile, but efficacy in the prevention of C difficile transmission must be determined by prospective clinical trials.

Cephalothin clearance of Staphylococcus aureus from two experimental infection sites in the presence and absence of local phagocytic cells

The clearance of Staphylococcus aureus from perforated peritoneal capsules which are accessible to phagocytic cells, and subcutaneous Visking chambers which exclude phagocytes, was studied simultaneously in eight rabbits implanted with both devices. Animals were treated with cephalothin, 100 mg/kg im every 8 h for sixteen doses, beginning 24 h after inoculation of the infection sites with S. aureus (cephalothin MIC 0.125 mg/l, MBC 0.5 mg/l). At the start of cephalothin, subcutaneous chambers contained a higher concentration of S. aureus (8.4 log10 cfu/ml) than peritoneal capsules (6.8 log10 cfu/ml, P less than 0.001). There was a significant bactericidal effect in subcutaneous chambers on both the third and sixth day of treatment (P less than 0.002), whereas in peritoneal capsules this did not occur until day six. The total reduction in bacterial count in subcutaneous chambers (7.0 log10 cfu/ml) was significantly greater than in capsules (4.4 log10 cfu/ml, P less than 0.002). The mean concentration of cephalothin in subcutaneous chambers (10.7 mg/l) was significantly higher than in peritoneal capsules (6.1 mg/l, P less than 0.02), but no difference in in-vitro killing of S. aureus was detected at these concentrations. We conclude that cephalothin clearance of S. aureus from a site accessible to phagocytes was delayed when compared to a phagocyte-inaccessible site.

In-111 Pseudomonas aeruginosa: a simple method of labeling live bacteria with a gamma-emitting radioisotope

We describe a simple and reliable technique for labeling Pseudomonas aeruginosa with a readily available commercial preparation of indium-111 (111In) oxine. Labeling of a heavy bacterial suspension with 500 mu Ci of commercially prepared 111In-oxine resulted in a yield of 0.0004 mu Ci of cell-associated 111In per 10(6) colony-forming units (CFU). The label was 88% bacterially associated and did not effect viability of the organism. Radiolabeling a gram-negative organism with 111In-oxine provides a non-toxic, stable gamma-emitting bacterial tracer.