Highly diluted urine is among the most commonly observed factors affecting the validity of urine testing for drug abuse. A minimum creatinine concentration of 20 mg/dL urine has been proposed as a marker for dilution of a urine sample. This study investigates the effect of water consumption on creatinine concentration, as well as its effect on specific gravity and osmolality. In this study, 22 subjects (17 women and 5 men) were included to determine the influence of sex and weight on the impact of excessive water consumption on these markers of urine dilution. The subjects consumed 0.5 L, 1.0 L, and 1.5 L of water, respectively, within 15 minutes.The mean minimum creatinine concentrations (Jaffé reaction) for the void 2 hours after fluid intake were 60.4 mg/dL, 15.8 mg/dL, and 10.9 mg/dL for the respective ingested volumes of water. Mean creatinine concentrations excreted by men were significantly higher than those excreted by women. Participants with a weight below 60 kg tended to excrete lower urine creatinine concentrations. 50% of the volunteers with a BMI < 20 kg/m 2 and 20% of the volunteers with a BMI > 20 kg/m 2 exhibited creatinine concentrations below the threshold value of 20 mg/dL. A similar pattern was established for gravity and osmolality. Due to its simple determination, creatinine may be preferred over specific gravity or osmolality. In order to evaluate the internal dilution of a urine sample for legally defensible drug testing, it may be necessary to account for sex and body weight.

Aims. The prognostic role of the proteases uPA and PAI-1, as well as tumor budding, in colon cancer, has been investigated previously. Methods. We provide 6-year follow-up data and results of the validation set. The initial test set and validation set consisted of 55 colon cancers and 68 colorectal cancers, respectively. Tissue samples were analyzed for uPA and PAI-1 using a commercially available Enzyme-Linked Immunosorbent Assay (ELISA). Tumor budding was analyzed on cytokeratin-stained slides. Survival analyses were performed using cut-offs that were determined previously. Results. uPA was not prognostic for outcome. PAI-1 showed a trend towards reduced cancer specific survival in PAI-1 high-grade cases (68 versus 83 months; P = 0.091). The combination of high-grade PAI-1 and tumor budding was associated with significantly reduced cancer specific survival (60 versus 83 months; P = 0.021). After pooling the data from both sets, multivariate analyses revealed that the factors pN-stage, V-stage, and a combination of tumor budding and PAI-1 were independently prognostic for the association with distant metastases. Conclusions. A synergistic adverse effect of PAI-1 and tumor budding in uni- and multivariable analyses was found. PAI-1 could serve as a target for anticancer therapy.

Purpose In forensics, entomological specimens can be used as additional/alternative matrices to detect xenobiotics when human specimens are limited in their application. Despite some advantages over implementing putrefied human remains, most medico-legal laboratories do not include entomotoxicological procedures as routine analytical methods. We thus applied two authentic cases to evaluate necrophagous larvae’s potential as complementary matrices for toxicological analysis after extensive postmortem decomposition. Methods Larvae and postmortem human samples, including hair, stomach contents, pericardial fluid, liver, lung, and skeletal muscle, were collected at autopsy. Samples were analyzed by liquid chromatography–tandem mass spectrometry and liquid chromatography–quadrupole time-of-flight mass spectrometry for pharmaceutical substances, illicit drugs, and new psychoactive substances, including synthetic cannabinoids, benzodiazepines, new synthetic opioids, and stimulants. Results Nearly all substances detected in human specimens, including several benzodiazepines and synthetic cannabinoids, were also detected in larvae. Surprisingly, some drugs, including the new psychoactive substances EAM-2201 and U-47700, were found exclusively in larvae and hair. The benzodiazepine etizolam was detected only in liver, lungs, and stomach contents, possibly resulting from characteristic tissue distribution in humans and/or larvae. Conclusions Antemortem external hair contamination with synthetic cannabinoids from side-stream smoke and postmortem hair contamination with substances in putrefaction fluids can be supposed in these cases. Our findings suggest that supplementary information can indeed be gained from analyzing larvae additional to those human specimens that are typically used for toxicological analysis after extensive postmortem decomposition. Nevertheless, these results represent merely two cases, requiring in-depth studies to determine whether such findings can identify acute intoxications as possible causes of death.

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A high volume of fluid can strongly reduce a drug's concentration in urine. Therefore, to detect diluted samples, the concentration of creatinine in urine is determined during testing drugs of abuse. If the concentration is below 20 mg creatinine/dl urine, the urine sample is usually rejected for drug testing. It should be examined whether creatine or creatinine ingestion can mask urine dilution by increasing the creatinine concentration. A total of 18 subjects drank 1.3 L of water and 0.2 L of orange juice on each of the three testing days: (1) without creatine, (2) with 20 g of creatine, and (3) with 20 g of creatine following incubation for 4 days in orange juice at room temperature; an acidic environment should promote conversion of creatine to creatinine. The lowest creatinine concentrations in urine were observed on average 2 h after fluid intake. At that time, ingestion of fluid without creatine, with creatine, and with creatine(ine)‐orange juice mixture resulted in mean values of 11.6, 22.5, and 28.3 mg creatinine/dl urine, respectively. It can be concluded that ingestion of creatine or creatinine can increase the concentration of creatinine in urine and thus mask dilution of a sample. The conversion of creatine in orange juice further increases availability of creatinine as it is obvious from urine creatinine concentration. Therefore, creatine ingestion during drug testing will give rise to negative results due to matrix adulteration. In a case of suspected creatine supplementation, the creatine content of the sample should be determined in addition to creatinine.