How to improve reward sensitivity - Predictors of long-term effects of a randomized controlled online intervention trial.

Background: Reward sensitivity is a central maintaining factor of depression. Current treatments fail at sufficiently and reliably modifying reward processing. Therefore, we employed interventions targeting reward sensitivity and evaluated the long-term efficacy of different online interventions, additionally exploring predictors of changes in reward sensitivity.

Effectiveness of behavioral activation and mindfulness in increasing reward sensitivity and reducing depressive symptoms - A randomized controlled trial.

Reward insensitivity is a potential key mechanism regarding the maintenance of depression. However, there is a lack of research examining and comparing the effectiveness of different psychological interventions in modifying reward insensitivity. This four-arm randomized controlled trial (RCT) investigated a two-week online intervention.

Transdiagnostic considerations of the relationship between reward sensitivity and psychopathological symptoms - a cross-lagged panel analysis.

Background: Reward sensitivity constitutes a potential key mechanism regarding the etiology and maintenance of mental disorders, especially depression. However, due to a lack of longitudinal studies, the temporal dynamics are not clear yet. Although some evidence indicates that reward processing could be a transdiagnostic mechanism of disorders, these observations could be also a product of comorbidity with depression.

Cannabinoid concentrations in spot serum samples 24-48 hours after discontinuation of cannabis smoking.

A blood concentration of tetrahydrocannabinol (THC) in the low nanograms-per-milliliter range is often claimed to result from drug use more than 24-48 h previously. The present investigation determined concentrations of cannabinoids in blood collected at least 24 h from smoking in an in-patient setting. During sampling, distinctive effects due to drug use could not be observed.

[Accidental death of disoriented persons in long term care facilities].

Five cases of accidental death occurring in connection with physical restraints in long-term care facilities are reported. The position in which the deceased were found, autopsy findings, police investigations as well as the evaluation of each case under criminal law are described. The investigations by the prosecution as well as the attention of the public media have meanwhile contributed to an improvement of the technical standards and a reduction of the risk in applying such restraints under the Law on Medical Devices.

[Comparative investigations on the uptake of basic substances into the human keratinocyte cell line HaCaT--a model for the uptake of xenobiotics into the keratinocytes of the hair follicle].

The human cell line HaCaT was used to study drug uptake by keratinocytes as an in-vitro model to elucidate drug incorporation into anagen hair follicle. The basic drugs under investigation were taken up very rapidly resulting in a concentration plateau in the keratinocytes which was dependent on the drug concentration in the cell culture medium. The results obtained for HaCaT clearly demonstrated the existence of a partition-equilibrium between the extracellular and intracellular drug concentrations.

An investigation of the stability of free and glucuronidated 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid in authentic urine samples.

Preanalytical stability of a drug and its major metabolites is an important consideration in pharmacokinetic studies or whenever the analyte pattern is used to estimate drug habits. Firstly, the stability of free and glucuronidated 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid (THCCOOH, THCCOOglu) in authentic urine samples was investigated. Random urine samples of cannabis users (n = 38) were stored at -20, 4, and 20 degrees C up to 15 days and up to 5 days at 40 degrees C, and alterations of the analyte pattern during storage were followed by liquid chromatography-tandem mass spectrometry.

In vitro contamination of hair by marijuana smoke.

Background: The deposition of cannabinoids on/into hair from environmental smoke can be considered as a potential source of drug findings in hair. We studied external uptake of cannabinoids from marijuana smoke, investigating possible influencing factors on drug uptake and the efficiency of decontamination procedures.

Methods: Strands of a natural hair sample were moistened with water, greased with sebum or sebum/sweat, or bleached or permed.

[Report on a methemoglobin-associated fatality].

An autoerotic fatality due to mechanical compression of the neck by a sophisticated construction used for breath control games is reported. The presence of signs of methemoglobinemia as well as an empty "poppers" flask found beside the passed indicated the use of volatile nitrites to enhance sexual pleasure. It was assumed that vasodilatation had caused a sudden unconsciousness with consecutive hanging.

[Serum cannabinoid levels 24 to 48 hours after cannabis smoking].

Low concentrations of THC and 11-hydroxy-THC in serum samples are often claimed not to result from recent cannabis use. Prediction of time of exposure is difficult, especially if distinctive features of drug use could not be observed. Therefore, the aim of the study was to investigate the presence of THC and 11-hydroxy-THC in serum samples as well as to obtain preliminary data on the analyte profile for a time window of 24-48 hours after discontinuation of cannabis smoking.

[Serum norharman and harman analysis using high pressure liquid chromatography/mass spectrometry and value of beta-carbolines as blood alcohol markers].

Firstly, a method for LC-MS/MS-analysis of the beta-carbolines norharman and harman in serum was established and validated. Secondly, serum samples from persons during ethanol loading conditions were investigated (n = 26). Norharman was regularly found positive only in persons with BAC > 1.

Partition coefficient, blood to plasma ratio, protein binding and short-term stability of 11-nor-Delta(9)-carboxy tetrahydrocannabinol glucuronide.

11-Nor-Delta(9)-carboxy tetrahydrocannabinol glucuronide (THCCOOglu) is a major metabolite of tetrahydrocannabinol in blood. Despite its mass spectrometric identification already in 1980, further physicochemical data of THCCOOglu have not been established. Therefore, the octanol/buffer partition coefficient P and the blood to plasma ratio b/p for THCCOOglu concentrations of 100 and 500ng/ml were investigated.

Preliminary approach to elucidate the role of pigment as a binding site for drugs and chemicals in anagen hair: differential uptake of 3H-haloperidol by pigment-producing compared to non-pigment-producing cell lines.

A striking difference was observed for cellular-bound drug in HaCaT and Sk-Mel-1 cells for a fixed drug exposure time of 72 h and varying 3H-haloperidol concentrations in the culture media. Drug uptake was dependent on drug concentration and linearly correlated for both the non-pigment- and the pigment-producing cells which however was different in magnitude. In an additional investigation the time course of drug uptake during 3H-haloperidol exposure (400 pmol/ml; 28 days) revealed increasing drug concentrations in the Sk-Mel-1 population, whereas drug concentrations in the keratinocytes reached a plateau within a short time period.

Preliminary approach to elucidate the role of pigment as a binding site for drugs and chemicals in anagen hairs: pigments as carriers for 3H-haloperidol in HaCaT/Sk-Mel-1 co-cultures.

In view of the melanin-binding characteristics of haloperidol and its differential uptake by pigment- and non-pigment-producing cells, a co-culture of HaCaT with Sk-Mel-1 cell lines was performed to investigate whether melanosomes act as carriers for drug molecules associated with the pigments. Initially, HaCaT and Sk-Mel-1 cells were separately cultivated in the presence of 3H-haloperidol (400 pmol/ml medium ) for 28 days followed by subsequent co-cultivation in the absence of 3H-haloperidol for 5 days. The transfer of pigments into the keratinocytes during co-culture was confirmed by transmission electron microscopy.

Stability of 11-nor-delta(9)-carboxy-tetrahydrocannabinol glucuronide in plasma and urine assessed by liquid chromatography-tandem mass spectrometry.

Background: Unconjugated 11-nor-Delta(9)-carboxy-tetrahydrocannabinol (THCCOOH) in blood and urine has been proposed as a valuable marker, but the glucuronide (THCCOOglu) is present in considerably higher concentrations than the parent drug. Acyl glucuronides have been shown to be potentially reactive conjugates, which may affect the in vitro metabolite pattern.

Methods: Extraction procedures and a liquid chromatography-tandem mass spectrometry assay were developed and validated to investigate the stability of THCCOOglu in urine and plasma.

[Serum beta-glucuronidase activity in polytrauma patients and in centrifuged autopsy blood samples].

The serum activity of beta-glucuronidase was investigated in 58 patients after severe trauma as well as in 43 autopsy cases. In 10 cases the enzyme activities in postmortem blood samples from the femoral vein were compared to those present in the correspondent heart blood samples. An elevated activity of beta-glucuronidase was observed in 14% of the patients within the first 36 h after severe trauma increasing to 62% in blood samples collected later on.

[Passive exposure in detection of low blood and urine cannabinoid concentrations].

Whenever small amounts of drugs are present in blood or urine samples, especially of substances that are preferentially smoked such as cannabinoids, the discrimination between active and passive inhalation may cause severe problems. The statement of a passive exposure by marijuana smoke has been scrutinized reviewing the literature. The pharmacokinetics of smoked marijuana as well as experimental data on cannabinoid concentrations in plasma and urine samples following passive exposure are summarized.

[Detection of cocaine in blood stains].

Cocaine is rapidly degraded in blood samples, and its degradation was found to be highly dynamic in nature. The analysis of blood spots dried on filter paper may provide a method to minimize the break-down of cocaine and to largely preserve the analytical profile of the parent drug and its hydrolysis products at the time of sampling. The short term stability of cocaine in 100 microL blood spots prepared from unpreserved and preserved (sodium fluoride, 0.

Saliva testing after single and chronic administration of dihydrocodeine.

In the present study, concentrations of dihydrocodeine and its metabolites in saliva and serum were compared after single low-dose and chronic high-dosage administration of the drug. In the first investigation, blood and saliva were collected periodically from six subjects after oral administration of 60 mg dihydrocodeine. In the second study, 20 subjects on oral dihydrocodeine maintenance provided single samples of blood and saliva simultaneously.

In vitro stability of cocaine in whole blood and plasma including ecgonine as a target analyte.

The in vitro stability of cocaine (COC) was monitored in fresh whole blood and plasma stabilized with potassium fluoride (0.25%) for as long as 15 days. The samples were stored at 4 degreesC, 20 degreesC and 40 degreesC.

Stability of morphine, morphine-3-glucuronide, and morphine-6-glucuronide in fresh blood and plasma and postmortem blood samples.

The present study was designed to determine the stability of morphine and its glucuronides in spiked fresh blood and plasma from live individuals as well as in four authentic postmortem blood specimens for a time interval of up to six months. The samples were stored in glass vials at -20 degrees C, 4 degrees C, and 20 degrees C. Additionally, spiked samples were exposed to light through window glass and subjected to a forced-degradation study at 40 degrees C.