The effect of tea catechins on the forensic identification of urine: Urine camouflage to evade drug tests.

BACKGROUND: We encountered a urine sample suspected of being mixed with tea, submitted by a suspect attempting to camouflage illegal drugs. Although urine should turn reddish-pink during a urea test with p-Dimethylaminocinnamaldehyde (DAC), this suspect's sample exhibited a blue coloration when tested with DAC. AIM: Our aim was to examine the influence and mechanism of green tea on various urine identification tests. RESULTS: Our examination revealed that DAC forms a compound with the urea in urine, resulting in a reddish pink coloration with a molecular weight of 217. However, it has been reported that DAC binds to polyphenols such as catechin. In the case of catechin, DAC binds to the C8 position, forming a compound that exhibits the highest absorption at 640 nm and appears blue. we investigated the effect of urine from volunteers who had consumed a large amount of catechin on the urea test with DAC. Additionally, we carried out quantitative analysis of catechin in urine by LC-MS/MS after enzymatic treatment with ß-glucuronidase. The concentration of urinary excreted catechin reached its peak approximately 3 to 4 h after ingestion. During the DAC test, urine samples collected 3 to 4 h after catechin ingestion displayed a bluish pink color, but not the blue color observed in the original suspect sample. CONCLUSION: This study investigated the impact of catechin on urine tests, revealing that a blue color in the DAC test indicates a high likelihood of camouflage by the suspect.

Volatile Hydrocarbon Analysis in Blood by Headspace Solid-Phase Microextraction: The Interpretation of VHC Patterns in Fire-Related Incidents.

A headspace solid-phase microextraction (HS-SPME) technique was used to quantitate the concentration of volatile hydrocarbons from the blood of cadavers by cryogenic gas chromatography-mass spectroscopy. A total of 24 compounds including aromatic and aliphatic volatile hydrocarbons were analyzed by this method. The analytes in the headspace of 0.1 g of blood mixed with 1.0 mL of distilled water plus 1 µL of an internal standard solution were adsorbed onto a 100-µm polydimethylsiloxane fiber at 0°C for 15 min, and measured using a GC-MS full scan method. The limit of quantitation for the analytes ranged from 6.8 to 10 ng per 1 g of blood. This method was applied to actual autopsy cases to quantitate the level of volatile hydrocarbons (VHCs) in the blood of cadavers who died in fire-related incidents. The patterns of the VHCs revealed the presence or absence of accelerants. Petroleum-based fuels such as gasoline and kerosene were differentiated. The detection of C8-C13 aliphatic hydrocarbons indicated the presence of kerosene; the detection of C3 alkylbenzenes in the absence of C8-C13 aliphatic hydrocarbons was indicative of gasoline; and elevated levels of styrene or benzene in the absence of C3/C4 alkylbenzenes and aliphatic hydrocarbons indicated a normal construction fire. This sensitive HS-SPME method could help aid the investigation of fire-related deaths by providing a simple pattern to use for the interpretation of VHCs in human blood.

Diagnostic approach to drug-screening tests for fatal diabetic ketoacidosis: forensic autopsy of a methamphetamine abuser.

To diagnose the cause of death in autopsy cases, systematic examinations, such as macroscopic, pathological, biochemical, and toxicological are important. In this case report, drug examinations also gave very useful information to diagnose the cause of death, fatal diabetic ketoacidosis (DKA). A female methamphetamine abuser in her forties was found dead lying on a hotel bed. Diagnosing her cause of death was difficult only from the macroscopic findings because there was no fatal and/or serious injury or disease. On toxicological examination, acetone was detected at a high concentration (682 microg/mL in blood, 887 microg/mL in urine) using gas chromatography (GC). Using gas chromatography-mass spectrometry (GC-MS), methamphetamine was detected in the blood, urine, hair, and visceral organs; however, these concentrations were low. At the same time, GC-MS examination revealed a high glucose peak. From the results of the biochemical examination of urine, acetoacetic acid was 1940 micromol/L, beta-hydroxybutyric acid was 14,720 micromol/L, and glucose was 4620 mg/dL. Histologically, Langerhans' islets in the pancreas were fibrotic and atrophic, and no insulin-immunoreactive cells were observed. The subsequent police investigation also revealed that she had contracted diabetes mellitus type 1; therefore, we concluded that her cause of death was DKA, due to a lack of insulin injection.

Changes in renal function and oxidative damage in methamphetamine-treated rat.

In this study, we observed renal damage and peroxidative injury as the acute or sub-acute effect of methamphetamine (MA) to determine whether MA intoxication can be diagnosed from immunohistochemical changes in the kidney. In addition, renal function was investigated in relation to the immunohistochemical changes. A single administration of MA (group I) (50mg/kg/ (i.p.)) and repeated administration (group II) (10mg/kg/day (i.p.) for 5 days) were designed as an acute model and a sub-acute or chronic model. Immunohistochemically, cell damage markers were observed. Then, renal function markers and minerals in blood were measured. Myoglobin and creatinine phosphokinase (CPK) in blood were also analyzed. In group I, ubiquitin immunoreactivity was enhanced only in the renal tubules. Creatinine increased, while K, Ca, and P decreased (P<0.01). CPK increased significantly (P<0.01). Therefore, it was suspected that MA might induce renal dysfunction with renal tubule damage. This damage might be related to leakage of CPK from muscle. In group II, 8-hydroxy-2'-deoxyguanosine (8-OH-dG) increased immunohistochemically and quantitatively (P<0.01). It was considered that oxidative DNA damage might be induced by repeated administration. It was considered that this study offers basic information for the evaluation of pathological changes in the kidney in MA-related autopsy cases.