Chlorprothixene in bodies after exhumation.

Toxicological analyses on body tissues and interpretation of results after exhumation are a challenging task. We report five cases in which toxicological analyses had to be performed due to suspicion of homicide by chlorprothixene intoxication. Exhumations had to be carried out following post mortem intervals in earth graves between two and five and a half years. Chlorprothixene and in some cases also its metabolites could be detected in liver and brain. For the interpretation of the results, chlorprothixene concentrations determined in brain should be used because of a relative isolation of the brain within the skull. However, a loss of organ weights due to post mortem degradation, which may lead to an increase of drug levels, should be taken into account.

Inhibition of 1,4-butanediol metabolism in human liver in vitro.

The conversion of 1,4-butanediol (1,4-BD) to gamma-hydroxybutyric acid (GHB), a drug of abuse, is most probably catalyzed by alcohol dehydrogenase, and potentially by aldehyde dehydrogenase. The purpose of this study was to investigate the degradation of 1,4-BD in cytosolic supernatant of human liver in vitro, and to verify involvement of the suggested enzymes by means of gas chromatography-mass spectrometry. The coingestion of 1,4-BD and ethanol (EtOH) might cause complex pharmacokinetic interactions in humans. Therefore, the effect of EtOH on 1,4-BD metabolism by human liver was examined in vitro. Additionally, the influence of acetaldehyde (AL), which might inhibit the second step of 1,4-BD degradation, was investigated. In case of a 1,4-BD intoxication, the alcohol dehydrogenase inhibitor fomepizole (4-methylpyrazole, FOM) has been discussed as an antidote preventing the formation of the central nervous system depressing GHB. Besides FOM, we tested pyrazole, disulfiram, and cimetidine as possible inhibitors of the formation of GHB from 1,4-BD catalyzed by human liver enzymes in vitro. The conversion of 1,4-BD to GHB was inhibited competitively by EtOH with an apparent K(i) of 0.56 mM. Therefore, the coingestion of 1,4-BD and EtOH might increase the concentrations and the effects of 1,4-BD itself. By contrast AL accelerated the formation of GHB. All antidotes showed the ability to inhibit the formation of GHB. In comparison FOM showed the highest inhibitory effectiveness. Furthermore, the results confirm strong involvement of ADH in 1,4-BD metabolism by human liver.

Detection of methylphenidate in the hair of children treated with Ritalin.

Hair samples were collected from 17 children (7-16 years of age) who had received methylphenidate therapy on a long-term basis. The dose was 10-60 mg per day. To 20 mg of pulverized hair, phosphate buffer and internal standard (norpethidine) were added. Extraction was performed by ultrasonic treatment, followed by isolation by alkaline extraction with isohexane. Derivatization with N-Methyl-bisheptafluorobutyric amide enabled gas chromatography-mass spectrometry analysis of the perfluorobutyryl derivatives in selected ion monitoring mode. The methylphenidate concentrations lay between 0.073 and 1.1 ng/mg hair. It was noted that at higher daily doses there was a tendency toward increased concentrations in the hair, but for testing of compliance, the incorporation into hair did not occur with the required high correlation between daily dose and concentration in the hair.

Arsenic in the cerebrospinal fluid of a patient receiving arsenic trioxide for relapsed acute promyelocytic leukemia with CNS involvement.

We report on a 42-year-old patient whose relapse of acute promyelocytic leukaemia (APL) included meningeal infiltration. Since he had previously experienced ATRA syndrome, he received arsenic trioxide (ATO) plus intrathecal therapy with cytarabine, prednisone, and methotrexate. We measured the concentration of arsenic in his cerebrospinal fluid (CSF). Arsenic showed a peak CSF concentration of 0.008 mg/l (0.11 micromol/l) and a nadir of 0.002 mg/l (0.027 micromol/l), both representing about 14% of blood levels. ATO thus crosses the blood-CSF-barrier when administered intravenously, but the concentration in CSF is probably not sufficient for treatment of meningeal leukemia.

Glucuronidation of aliphatic alcohols in human liver microsomes in vitro.

The glucuronidation of several short-chained aliphatic alcohols in vitro, with the use of human liver microsomes (HLM) as catalyst, was performed, and the kinetics were studied. The concentrations of the glucuronides were determined by gas chromatography-mass spectrometry after derivatization to the trimethylsilyl compounds. Alcohols from ethanol to pentanols were found to couple with activated glucuronic acid in HLM to a widely varying amount. For analytic reasons the glucuronide of methanol, which is formed after methanol consumption in human beings in vivo, could not be determined. The length of the alkyl chain played the decisive role in the maximum turnover rate of the glucuronidation. The affinity of the alcohols to UDP-glucuronosyltransferase (UDPGT), which catalyzes the glucuronidation reaction, was shown to depend strongly on their structure. Alcohols with a very short alkyl chain and secondary alcohols were glucuronidated much more slowly in comparison with findings for the longer chain primary alcohols and showed less affinity to UDPGT. The alcohols mutually inhibited glucuronidation. However, ethanol inhibited the glucuronidation of isopentanol or n-pentanol only in high concentrations, whereas the two pentanols inhibited each other to a high degree. The glucuronidation of aliphatic alcohols is probably catalyzed by only one of several very similar enzymes of the UDPGT. This finding was indicated by the fact that the Michaelis-Menten constants of the alcohols--with the use of different lots of the HLM from different liver donors--had nearly the same values.

Cyclooxygenase-2 inhibitors suppress the growth of human hepatocellular carcinoma implants in nude mice.

Cyclooxygenase (COX)-2 is expressed in hepatocellular carcinomas (HCCs) and HCC cell lines. COX-2 inhibition strongly suppresses growth of HCC cells in vitro by inducing apoptosis and reducing proliferation. Here, we evaluate the in vivo effects and mechanism of COX-2 inhibition of human HCC cell line derived xenotransplanted tumors in nude mice. Firstly, nude mice were treated with a COX-2 specific inhibitor (meloxicam) or a non-specific inhibitor (sulindac) starting 5 days prior to tumor cell injection. After 35 days mice were killed and tumors were analyzed morphologically and assayed for proliferation (Ki67), apoptosis (M30) and COX-2 expression. Secondly, mice were treated with meloxicam or sulindac after tumors had reached a diameter of at least 0.2 cm. COX-2 expression was maintained in implant tumors at levels comparable with parental cells. Selective COX-2 inhibition led to a significant reduction of tumor growth and weight. COX-2 inhibition had a significant anti-proliferative and pro-apoptotic effect on tumor cells. These results demonstrate that under experimental conditions selective COX-2 inhibition suppresses solid HCC growth in vivo and, therefore may have preventive and therapeutic potential for human HCCs.

[Fatal outcome of Ecstasy overdose]. / Todesfall nach Ecstasy-Uberdosierung.

Consumption of amphetamine derivatives has considerably increased in Germany since the early nineties. Again and again intoxications with lethal outcome have also been reported, especially after physical activities such as intensive dancing. The authors present a case of an obviously suicidal intoxication of a 21-year-old man who was found dead with marked cuts on the right forearm. Toxicological tests showed in particular 3, 4-methylene-dioxymethamphetamine (MDMA). The results of the hair analysis revealed chronic consumption, but no cellular liver damage could be demonstrated. When examining the body fluids and organs, the highest concentrations by far were measured in the lungs (36.6 mg/kg), the liver (29.7 mg/kg) and the brain (29.1 mg/kg). The concentration in heart blood amounted to 10.8 mg/kg and was thus markedly higher than in peripheral blood (7.2 mg/kg). In the muscles concentrations ranged between 14.3 mg/kg and 20.2 mg/kg. On the basis of these concentrations and the available pharmacokinetic data the amount of MDMA probably consumed is assessed. It is demonstrated that for this assessment the concentrations in the muscular system are of special importance, as redistribution of highly lipophilic substances from the surrounding tissue is possible also in peripheral blood.