Minori Nishiguchi

An autopsy case of combined drug intoxication involving verapamil, metoprolol and digoxin

We present here a fatal poisoning case involving verapamil, metoprolol and digoxin. A 39-year-old male was found dead in his room, and a lot of empty packets of prescribed drugs were found near the corpse. The blood concentrations of verapamil, metoprolol and digoxin were 9.2 microg/ml, 3.6 microg/ml and 3.2 ng/ml, respectively. The cause of death was given as cardiac failure, hypotension and bradycardia due to a mixed drug overdose of verapamil, metoprolol and digoxin, based on the results of the autopsy and toxicological examination. We speculate that the toxicity of verapamil is potentiated by drug interaction with metoprolol and digoxin.

Bromide detection in blood using energy dispersive X-ray fluorescence; a chemical marker supportive of drowning in seawater

Energy dispersive X-ray fluorescence spectrometry (EDX) enables rapid, non-destructive, multi-elemental analysis. Using EDX, bromide was detected in seawater but not in freshwater. We applied EDX to the detection of bromide in cardiac blood from medico-legal autopsy cases to obtain additional evidence supportive of seawater drowning. Bromide was detected in the blood of 4 out of 10 victims drowned in seawater. In contrast, bromide concentrations were below the quantification limit in both victims from freshwater drowning and non-drowning controls. No postmortem invasion of bromide was observed in animal experiments of postmortem immersion in seawater. These results indicate that the detection of bromide in blood by EDX could be a chemical marker supportive of drowning in seawater.

Simultaneous analysis of acephate and methamidophos in human serum by improved extraction and GC-MS

A detailed procedure for simple and rapid analysis of acephate, an organophosphorous pesticide, and its metabolite methamidophos in human serum by gas chromatography-mass spectrometry was established. The method included solid-phase extraction with activated charcoal, which gave high recoveries of both analytes. After validation of the method, it was successfully applied to a serum sample obtained from an actual poisoning case. The present method seems very useful, especially in forensic and environmental toxicology.

Application of energy dispersive X-ray fluorescent spectrometry (EDXRF) in drug-related cases.

We applied here energy dispersive X-ray fluorescent spectrometry (EDXRF) to two medico-legal autopsy cases of bromvalerylurea ingestion. Rapid elemental analysis using EDXRF identified bromide in blood, urine and stomach contents of victims during autopsy. The present cases indicate that screening with EDXRF, an instrument suitable for non-destructive, rapid elemental analysis, provides useful information for identification of drugs.

Detection of metallic elements from paraffin-embedded tissue blocks by energy dispersive X-ray fluorescence spectrometry

Energy dispersive X-ray fluorescence spectrometry (EDX) enables rapid, non-destructive, multi-elemental analysis. Using EDX, lead and some other metallic elements were detected in paraffin-blocks in which skin samples from a gunshot wound were embedded. Lead was not identified in control samples from non-injured cases. These findings indicate that EDX is a useful method for rapid non-destructive analysis of paraffin-embedded blocks. This technique can provide scientific evidence for identification of a firearm even after storing the sample for a long time.

Decreased histamine-stimulated phosphoinositide hydrolysis in the cerebral cortex of a rat line selectively bred for high alcohol preference.

This study sheds light on the comparative analysis of agonist-stimulated phosphoinositide (PI) hydrolysis in the cerebral cortex of alcohol-naïve rats from established lines selectively bred for low alcohol preference (LAP) and high alcohol preference (HAP). The effect of histamine (1.0 mM), but neither norepinephrine (0.1 mM) nor carbachol (0.5 mM), on PI hydrolysis was significantly reduced in HAP rats (0.4 ± 5.0 fmol/mg protein [3H]inositol phosphates formed over basal) compared with LAP rats (25.5 ± 10.0 fmol/mg protein). The contents of monoamines (dopamine, norepinephrine, and serotonin) and histamine in the cerebral cortex did not significantly differ between LAP and HAP rats, nor did the contents of their metabolites, except 3-methoxy-4-hydroxyphenylglycol (one of the metabolites of norepinephrine) and Nτ-methylhistamine, which was not detected in our system. The histamine stimulatory effect was unchanged in the cerebral cortex of an intact Wistar rat that was treated with intraperitoneal injection of alcohol (1.0 g/kg once per day for 14 days). The results of the current study indicate that the decrease in the histamine effect on PI hydrolysis in HAP rats might be attributed to that particular rat line.

An Autopsy Case of Fatal Methemoglobinemia due to Ingestion of Sodium Nitrite

We herein present an autopsy case of fatal methemoglobinemia due to suicidal ingestion of sodium nitrite. A man in his 30s who had exhibited mild depression was found dead in his house. A glass containing a white turbid solution and a suicide note were found on the table near the decedent. At autopsy, the lividity of the face and back was greenish gray, and the blood was tinted a chocolate brown color. Toxicological analysis of nitrite and nitrate using a colorimetric method showed that the nitrite concentrations were <0.05 and 0.09 μg/mL and that the nitrate concentrations were 71.69 and 83.48 μg/mL in the heart and femoral blood, respectively. Biochemical analysis after death showed that the level of methemoglobin was 83.4% by spectrophotometry. We conclude that the cause of death was severe methemoglobinemia following acute poisoning induced by sodium nitrite ingestion, although the blood nitrite concentration did not reach the fatal level.

An Autopsy Case of a Nonprescription Aspirin Overdose and Chlorine GasExposure

We report an autopsy case of a man whose death was caused by a combination of aspirin (acetylsalicylic acid) poisoning and chlorine gas inhalation. Toxicological analysis of aspirin and salicylic acid using high performance liquid chromatography with photodiode array detection showed that the concentration of salicylic acid was 444.7 μg/ mL in the heart blood and 68.3 μg/g in the brain. Existence of chlorine gas was proven, in the form of chloride ions, in a plastic bag near the body using energy dispersive X-ray fluorescence spectrometry. It was thought that damage to the mucosa, respiratory tract and skin had been caused by hydrochloric and hypochlorous acid associated with chlorine gas inhalation that rapidly aggravated the respiratory distress and pulmonary edema caused by aspirin and salicylic acid. This case report shows that the risk of death is increased when two substances, aspirin and chlorine gas, are taken through different routes, even if the concentration of one of them does not reach the lethal dose.

Determination of acephate and methamidophos in tissues: appearance of matrix effect in gas chromatography–mass spectrometry

A simple and reliable method to determine acephate and methamidophos in mammalian tissues is presented. The method includes solid-phase extraction of tissue extracts with active carbon cartridges followed by gas chromatography–mass spectrometry analysis. During the study, a matrix effect was observed especially at low concentrations of acephate and methamidophos in serum and in brain. To minimize the effect, we prepared calibration curves with relatively short ranges. The validation data, such as the linearity of calibration curves, limits of detection, and coefficients of variation for recovery rates, were generally satisfactory. The present method is useful for determination of acephate and methamidophos in mammalian tissues because of its simplicity and speed, keeping in mind the presence of the matrix effect.

An autopsy case of imipramine poisoning.

We present a fatal imipramine poisoning. Quantitative analysis of imipramine and its metabolite, desipramine, was performed by high-performance liquid chromatography. The concentrations of imipramine and desipramine were 18.67 μg/mL and 6.21 μg/mL in heart blood and 6.90 μg/mL and 1.77 μg/mL in the femoral venous blood, respectively. We concluded that the cause of death was due to imipramine poisoning.