Time to return for second donation was associated with total number of donations made and with return rate for subsequent returns. Age was the strongest predictor of high donation frequency and early-return rate. Relationships between interdonation interval and the number of future donations may prove useful in understanding return behavior and developing donor recruitment and retention strategies.

The traditional Japanese medicine rikkunshito ameliorates the nitric oxide-associated delay in gastric emptying. Whether rikkunshito affects gastric motility associated with 5-hydroxytryptamine (serotonin: 5-HT) receptors or dopamine receptors is unknown. We examined the effects of rikkunshito on the delay in gastric emptying induced by 5-HT or dopamine using the phenol red method in male Wistar rats. 5-HT (0.01–1.0 mg kg−1, i.p.) dose dependently delayed gastric emptying, similar to the effect of the 5-HT3 receptor agonist 1-(3-chlorophenyl) biguanide (0.01–1.0 mg kg−1, i.p.). Dopamine also dose dependently delayed gastric emptying. The 5-HT3 receptor antagonist ondansetron (0.04–4.0 mg kg−1) and rikkunshito (125–500 mg kg−1) significantly suppressed the delay in gastric emptying caused by 5-HT or 1-(3-chlorophenyl) biguanide. Hesperidin (the most active ingredient in rikkunshito) suppressed the 5-HT-induced delayed gastric emptying in a dose-dependent manner, the maximum effect of which was similar to that of ondansetron (0.4 mg kg−1). The improvement obtained by rikkunshito or ondansetron in delaying gastric emptying was completely blocked by pretreatment with atropine. Rikkunshito appears to improve delay in gastric emptying via the antagonistic action of the 5-HT3 receptor pathway.

Intra- and postoperative infusion of low-dose ketamine reduced cumulative morphine consumption and antiemetic requirement for 48 h after surgery.

The demographic and geographic determinants of human T lymphotropic virus types I and II (HTLV-I and -II) are not well defined in the United States. Antibodies to HTLV-I and -II were measured in 1.7 million donors at five US blood centers during 1991-1995. Among those tested, 156 (9.1/10(5)) were HTLV-I seropositive and 384 (22.3/10(5)) were HTLV-II seropositive. In contrast to monotonously increasing age-specific HTLV-I seroprevalence, HTLV-II prevalence rose until age 40-49 years and declined thereafter, suggesting a birth cohort effect. HTLV-II infection was independently associated with an age of 40-49 years (odds ratio [OR], 12.4; 95% confidence interval [CI], 8.8-18.9), female sex (OR, 3.3; 95% CI, 2.6-4.1), high school or lower education (OR, 1.7; 95% CI, 1.3-2.1), hepatitis C seropositivity (OR, 25.0; 95% CI, 17.5-35.8), and first-time blood donation (OR, 3.6; 95% CI, 2.8-4.7). HTLV-II seroprevalence was highest at the two West Coast blood centers. These data are consistent with a 30-year-old epidemic of HTLV-II in the United States due to injection drug use and secondary sexual transmission and with an apparent West Coast focus.

The mortality experience of 33,833 US Army and Marine Corps Vietnam veterans who died during 1965-1988 was compared with that of 36,797 deceased non-Vietnam veterans using proportionate mortality ratios (PMRs). Military service information was abstracted from military personnel records and cause of death information recorded from death certificates. Army Vietnam veterans had statistically significant excesses of deaths from laryngeal cancer (PMR = 1.38) and lung cancer (PMR = 1.08). There was an excess of external causes (PMR = 1.03), including motor vehicle accidents (PMR = 1.03) and accidental poisonings (PMR = 1.17). In contrast to Army Vietnam veterans, the results for Marine Vietnam veterans varied according to the referent population used. When compared with non-Vietnam veterans, Marine Vietnam veterans had significantly elevated PMRs for lung cancer (PMR = 1.17) and skin cancer (PMR = 1.33). There was also a significant excess of external causes of death (PMR = 1.06), accidental poisonings (PMR = 1.19), and homicides (PMR = 1.16) compared with all non-Vietnam veterans.