The flavanones naringenin and hesperetin exhibit estrogenic, anticarcinogenic and antioxidative properties. Orange juice and grapefruit juice contain high amounts of these compounds, and therefore their intake from the diet can be relatively high. No data are available regarding plasma concentrations or plasma kinetics of flavanones. The objectives of this study were to develop methods allowing the analysis of naringenin and hesperetin from plasma and urine and to study their plasma kinetics and urinary excretion. We also wanted to assess whether plasma or urine flavanone concentrations can be used as biomarkers of intake. Healthy volunteers ingested orange juice (five women and three men) or grapefruit juice (two women and three men) once (8 mL/kg). Eleven blood samples and urine were collected between 0 and 24 h after juice administration. Flavanones were analyzed by HPLC with electrochemical detection. Naringenin and hesperetin were bioavailable from the studied juices, but interindividual variation in bioavailability was remarkable. The resulting plasma concentrations were comparatively high, and the peak plasma concentrations (C(max)) were 0.6 +/- 0.4 micromol/L (means +/- SD) for naringenin from orange juice and 6.0 +/- 5.4 micromol/L for naringenin from grapefruit juice. The corresponding value for hesperetin from orange juice was 2.2 +/- 1.6 micromol/L. The elimination half-lives were between 1.3 and 2.2 h, and therefore plasma concentrations reflect short-term intake. The relative urinary excretion varied depending on the flavanone source and dose and was 30.2 +/- 25.5% and 1.1 +/- 0.8% for naringenin from grapefruit juice and orange juice, respectively, and 5.3 +/- 3.1% for hesperetin from orange juice. The considerable difference in the relative urinary excretion of naringenin from the two juices was most likely caused by dose-dependent renal clearance rather than differences in bioavailability (as indicated by the similar C(max)-to-dose ratios). The results indicate that urine flavanone concentrations are not good biomarkers of dietary intake. We conclude that because of the relatively high concentrations of flavanones in plasma after ingestion of orange juice or grapefruit juice, considerable health effects could ensue in individuals consuming them regularly.

Methylphenidate is an effective treatment for reducing intravenous drug use in patients with severe amphetamine dependence.

No abstract

Betaine, i.e., trimethylglycine, is linked to homocysteine metabolism. A 3-mo daily betaine supplementation decreased even normal plasma total homocysteine (tHcy) concentrations in humans. The pharmacokinetic characteristics and metabolism of betaine in humans have not been investigated in detail. The aim of this study was to assess the pharmacokinetics of orally administered betaine and its acute effect on plasma tHcy concentrations. Healthy volunteers (n = 10; 3 men, 7 women) with normal body weight (mean +/- SD, 69.5 +/- 17.0 kg), 40.8 +/- 12.4 y old, participated in the study. The betaine doses were 1, 3, and 6 g. The doses were mixed with 150 mL of orange juice and ingested after a 12-h overnight fast by each volunteer according to a randomized double-blind crossover design. Blood samples were drawn for 24 h and a 24-h urine collection was performed. Orally administered betaine had an immediate and dose-dependent effect on serum betaine concentration. Single doses of 3 and 6 g lowered plasma tHcy concentrations (P = 0.019 and P < 0.001, respectively), unlike the 1-g dose. After the highest dose, the concentrations remained low during the 24 h of monitoring. The change in plasma tHcy concentration was linearly associated with betaine dose (P = 0.006) and serum betaine concentration (R2 = 0.17, P = 0.025). The absorption and elimination of betaine were dose dependent. The urinary excretion of betaine seemed to increase with an increasing betaine dose, although a very small proportion of ingested betaine was excreted via urine. In conclusion, a single dose of orally administered betaine had an acute and dose-dependent effect on serum betaine concentration and resulted in lowered plasma tHcy concentrations within 2 h in healthy subjects.

We assessed the prevalence and associations of symptoms of insomnia in patients with acute ischemic stroke, and evaluated whether mianserin as a sedative antidepressant is beneficial in the treatment of poststroke insomnia. One hundred consecutively hospitalized patients were randomized to receive 60 mg/day of mianserin (n = 51) or placebo for 1 year in a double-blind trial with a 6-month follow-up after the therapy. Symptoms of insomnia were assessed with the three insomnia-related items of the Hamilton Depression Scale; patients were defined as insomniacs if any of these items was positive. Complaints of insomnia occurred in 68% of patients on admission, and in 49% at 18 months, and they were as frequent in all subgroups of patients. From 2 months, symptoms of insomnia were associated independently with depression. Living alone before stroke (at 0 and 2 months) and age (at 12 months) were other independent predictors of insomnia. The rate of recovery as evaluated by the insomnia score was more rapid in patients on mianserin than in those on placebo. At 2 months, the scores were significantly different favoring mianserin treatment (1.3 vs. 0.8, p = 0.02). We conclude that insomnia is a common complaint after ischemic stroke. Mianserin had a beneficial influence on the recovery from symptoms of insomnia, even though the intensity of poststroke depression was low.

These results show that COC- and MAZ-induced reward-related neurochemical and behavioral effects, preferentially those implicated in development of conditioned reward, are modified by the 5-HT(3) blockade. In contrast to COC and MAZ, the changes induced by MP, which has less effect on the serotonergic system, remain unchanged. Thus it appears that involvement of a serotonergic component in the mechanism of action of a drug could be a prerequisite for effective antagonism by 5-HT(3) receptor blockers.

No abstract

On group level, isotretinoin seems not to be typically associated with treatment-emergent depression or suicidal ideation among young men. However, the possibility that individual patients may be susceptible for mood effects of isotretinoin as a rare idiosyncratic reaction can not be excluded.