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Being a stable metabolite of hydrogen sulfide, thiosulfate has been utilized as an index for hydrogen sulfide poisoning (HSP). Thiosulfate analysis is mainly performed using gas chromatography/mass spectrometry (GC-MS) due to its high sensitivity and specificity. The GC-MS analysis requires two-step derivatizations of thiosulfate, and the derivative is not stable in solution as it has a disulfide moiety. To resolve this stability issue, we developed a novel analytical method using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for monitoring the pentafluorobenzyl derivative of thiosulfate (the first reaction product of the GC-MS method) in this study. The established method exhibited high reproducibility despite being a more simplified and rapid procedure compare to the GC-MS method. Phenyl 4-hydroxybenzoate was used as an internal standard because 1,3,5-tribromobenzene which had been used in the GC-MS method was not suitable compound for LC-MS/MS with Electrospray ionization (ESI) negative detection. The linear regression of the peak area ratios versus concentrations was fitted over the concentration ranges of 0.5-250μM and 0.25-250μM in blood and urine, respectively. The validation results satisfied the acceptance criteria for intra- and inter-day accuracy and precision. Blood and urine samples from 12 suspected HSP cases were tested using this method. The thiosulfate concentration detected in the sample coincided well with that determined at the scene of each HSP accident., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Blood and tissue samples from a forensic autopsy of a man in his late 60s, who developed dementia and died of multiple head traumas due to a fall from a moving vehicle, contained certain amounts of n-butane and i-butane. The concentration of n-butane was in the range of 0.48-70.5 μL/g, which would be considered as toxic or lethal levels. We had to distinguish whether the cause of his unexplained behavior was due to his pre-existing condition (dementia), or from a confused state induced by butane abuse. No traces of butane use were found at the scene. Police investigation revealed that a propellant used in an anticontagious plugging spray had been administered to him during a postmortem treatment in the emergency hospital. In order to prove the postmortem butane diffusion had resulted from the spray administration and to estimate the diffused concentration, experimental simulation was conducted by using rats. As a result of postmortem treatment with the spray, n-butane at concentrations of 0.54-15.5 μL/mL or g were found in the rat blood and tissues. In this case, we provided further evidence that the postmortem butane diffusion, caused by using the anticontagious plugging spray containing butane gas as a propellant administered to a cadaver during a postmortem procedure prior to forensic autopsy, should be distinguished from cases of actual butane poisoning., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Analysis of oxyhemoglobin (O2-Hb) saturation levels in the left and right heart blood is useful in the assessment of exposure to cold surroundings before death. We quantified conventional subjective visual evaluation of O2-Hb saturation levels and developed useful diagnostic criteria for fatal hypothermia: O2-Hb saturation in the left heart blood (L-O2Hb) was ⩾36%, the O2-Hb saturation gap between the left and right heart blood (L-R gap) was ⩾13%, and the O2-Hb saturation ratio of the left to right heart blood (L/R ratio) was ⩾1.8. When we used L-O2Hb of ⩾36% as a basic criterion and applied a further criterion of an L-R gap of ⩾13% or an L/R ratio of ⩾1.8, these criteria registered a sensitivity level of ⩾86% and specificity level of ⩾93% for the diagnosis of fatal hypothermia. This method can be useful for determining fatal hypothermia in connection with conventional autopsy findings, as well as histological and biochemical markers., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Amplification of fluorescently labeled products is one of the most popular methods for genotyping genetic variations. Two-step amplification using fluorescent universal primers simultaneously produces multiple targeted fragments labeled with fluorescent dyes, and this strategy is applicable to large-scale, cost-effective genotyping. In this study, we developed a fast PCR-based, multiple short tandem repeat (STR) genotyping method using fluorescent universal primers containing locked nucleic acids (LNAs). Four amplification reactions, each assaying six or seven markers and using 0.5-1.0 ng of genomic DNA, produced obvious Fam-labeled peaks in all 26 loci tested (25 autosomal STRs and amelogenin). The overall amplification time was 37 min. Moreover, fluorescent signals for the 25 STRs obtained from LNA-containing primers were 1.5-9.0 fold higher compared to those from non-LNA primers. Using genomic DNA from 120 Japanese individuals, 16 out of the 25 STRs had observed heterozygosity greater than 0.7. Some of these 25 STRs also had high discriminatory power, similar to that of the 13 core STRs in the Combined DNA Index System dataset. The probability of incorrectly assigning a match based on the accumulated matching probability for these 25 STRs is 1.2 × 10(-22), and their combined use can provide robust information for Japanese forensics., (Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.)

We report findings from an autopsy of a male in his 40s who died of a brain stem hemorrhage associated with cerebral amyloid angiopathy (CAA), senile plaques (SPs) and neurofibrillary tangles (NFTs), which are histopathological changes associated with Alzheimer's disease (AD). Our immunohistochemical study demonstrated amyloid β (Aβ) deposition in the small cerebral arteries and SPs. Although hypertension (178/132 mmHg) was detected, the subject was not treated accordingly. CAA coupled with hypertension might have caused the intracerebral hemorrhage (ICH)., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Short insertion/deletion (Indel) polymorphisms of approximately 2-6 bp are useful as biallelic markers for forensic analysis, and the application of Indel genotyping as a supplementary tool would improve human identification accuracy. We examined the allele frequencies of 37 autosomal Indels in the Japanese population and developed a novel dual-color genotyping method for human identification on the basis of universal fluorescent PCR, including the sex-typing amelogenin locus. Target genomic fragment sizes for 38 Indels were 49-143 bp. We analyzed these Indels in 100 Japanese individuals using the M13(-47) sequence as a universal primer. For dual-color genotyping, we designed a novel universal primer with high amplification efficiency and specificity. Using FAM-labeled M13(-47) and HEX-labeled modified M13(-47) primers, fluorescent signals at all loci were clearly distinguished in two independent multiplex PCRs. Average minor allele frequency was 0.39, and accumulated matching probability was 2.12 × 10(-15). Complete profiles were successfully amplified with as little as 0.25 ng of DNA. This method provides robust, sensitive, and cost-effective genotyping for human identification., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Paraquat is a commonly used herbicide; however, it is highly toxic to humans and animals. Exposure to paraquat causes severe lung damage, leading to pulmonary fibrosis. However, it has not been well clarified as how paraquat causes cellular damage, and there is no established standard therapy for paraquat poisoning. Meanwhile, endoplasmic reticulum stress (ERS) is reported to be one of the causative factors in many diseases, although mammalian cells have a defense mechanism against ERS-induced apoptosis (unfolded protein response). Here, we demonstrated that paraquat changed the expression levels of unfolded protein response-related molecules, resulting in ERS-related cell death in human lung epithelial A549 cells. Moreover, treatment with sodium tauroursodeoxycholate (TUDCA), a chemical chaperone, crucially rescued cells from death caused by exposure to paraquat. These results indicate that paraquat toxicity may be associated with ERS-related molecules/events. Through chemical chaperone activity, treatment with TUDCA reduced paraquat-induced ERS and mildly suppressed cell death. Our findings also suggest that TUDCA treatment represses the onset of pulmonary fibrosis caused by paraquat, and therefore chemical chaperones may have novel therapeutic potential for the treatment of paraquat poisoning., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Amplification/hybridization-based genetic analyses using primers containing locked nucleic acids (LNAs) present many benefits. Here, we developed a novel design for universal fluorescent PCR using LNAs. Universal fluorescent PCR generates intermediate nonlabeled fragments and final fluorescent fragments in a two-step amplification process that uses locus-specific primers with universal tails and universal fluorescent primers. In this study, a few standard nucleotides were replaced with LNAs only in the fluorescent universal primers. The sequence of the fluorescent universal primer significantly affected the amplification efficiency. For primers with three LNAs, the fluorescent primers with stable M13(-47) sequences provided the most efficient signal (approximately tenfold higher than the primers with M13(-21) sequences at lower Tm values). Moreover, AT-rich LNA substitutions in the fluorescent primers produced much lower amplification efficiencies than GC-rich substitutions. GC-rich LNAs produced greater differences in Tm values among primers, and resulted in the preferential production of fluorescently labeled amplicons. The specificity and sensitivity of LNA-containing fluorescent primers were assessed by genotyping eight STRs in Japanese individuals, and full STR profiles could be generated using as little as 0.25 ng of genomic DNA. The method permitted clear discrimination of alleles and represents sensitive STR genotyping at a reduced cost., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

When the population parameters of drug pharmacokinetics in the human body system are known, the time-course of a certain drug in an individual can generally be estimated by pharmacokinetics. In the present two cases where methamphetamine abusers were suspected to have inflicted mortalities in traffic accidents, the time-elapse or duration immediately after methamphetamine injection to the time when the accidents occurred became points of contention. In each case, we estimated the time-course of blood methamphetamine after the self-administration in the suspects using a 2-compartment pharmacokinetic model with known pharmacokinetic parameters from the literatures. If the injected amount can be determined to a certain extent, it is easy to calculate the average time-elapse after injection by referring to reference values. However, there is considerable individual variability in the elimination rate based on genetic polymorphism and a considerably large error range in the estimated time-elapse results. To minimize estimation errors in such cases, we also analyzed genotype of CYP2D6, which influenced methamphetamine metabolism. Estimation based on two time-point blood samples would usefully benefit legal authorities in passing ruling sentences in cases involving similar personalities and circumstances as those involved in the present study., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Discrimination of Alu insertions is a useful tool for geographic ancestry analysis, and is usually performed by Alu element amplification and agarose gel electrophoresis. Here, we have developed a new fluorescence-based method for multiple Alu genotyping in forensic identification. Allele frequencies were determined in 70 Japanese individuals, and we selected 30 polymorphic Alu insertions. Three primers were designed for each Alu locus to discriminate alleles using the 3-6 bp differences in amplicon sizes. Furthermore, we classified the amplification primers for the 30 loci into three different sets, and PCR using each set of primers provided 10 loci fragments ranging from 50 to 137 bp. Based on population data, the probability of incorrectly assigning a match was 3.7×10(-13). Three independent amplifications and subsequent capillary electrophoresis enabled the sensitive genotyping of small amounts of DNA, indicating that this method is suitable for identifying individuals of Japanese ethnicity., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Zonisamide, which is commonly prescribed at high doses (200-400 mg/day) for the treatment of partial seizures, has recently been used at a low dose (25 mg/day) for improving parkinsonian syndrome. However, the molecular mechanisms that underlie the antiparkinsonian effects of zonisamide have not been clarified. Here we show that low micromolar concentrations of zonisamide prevented cleavage of caspase-3 and cell death in human dopaminergic SH-SY5Y neuroblastoma cells that were subjected to endoplasmic reticulum stress induced by tunicamycin or 6-hydroxydopamine. Hypodense zonisamide increased the expression levels of SEL1L, which is known to stabilize the ubiquitin ligase HRD1. Indeed, upregulation of HRD1 protein was observed. Thus, the results of this study strongly suggest that low concentrations of zonisamide inhibit neuronal cell death by increasing HRD1 protein levels in patients with Parkinson's disease. Consequently, in addition to the treatment of Parkinson's disease, the therapeutic potential of zonisamide should be considered for the treatment of several neurodegenerative disorders with pathophysiological mechanisms involving endoplasmic reticulum stress.

The ligase detection reaction (LDR) is a highly specific genotyping method for single nucleotide variations. Although LDR typically discriminates single nucleotide polymorphism (SNP) alleles at the 3' end of so-called LDR discriminating probes, we designed probes in which the position of nucleotide differences for discrimination was shifted to the second and third nucleotides from the 3' end. Using the 3'-modified probes, we targeted SNPs of the human ABO group and investigated the specificity and efficiency of ligation by a universal LDR assay. We demonstrated that one or two nucleotide shifts of differences in discriminating probes improve the allele balance in detecting both base substitutions and short deletions. In regard to short deletions, moreover, the shifts of nucleotide differences in discriminating probes form the perfect-machted or multiple-mismatched structures (the bulge structures) in the discriminating probe-target DNA duplex and may contribute to enhance ligation efficiency., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

We developed a new method for forensic ABO genotyping based on a universal reporter primer (URP) system. This allows for the simultaneous detection of six single nucleotide polymorphism (SNP) sites in the ABO gene (nucleotide positions 261, 297, 526, 703, 796, and 803). This URP system provides obvious peaks, ranging from 82 to 151 bp in length. ABO genotypes were classified and successfully genotyped by our method, including minor alleles that may cause a discrepancy between the genetic data and serological phenotypes. Full profiles were identified using as little as 0.1 ng (0.05 ng ⁄ reaction) of standard K562 and 9947A DNA. Moreover, the success rate of genotyping from a URP system was much higher than that from a conventional primer extension method in degraded DNA. This method enables simple and rapid detection of multiple SNP sites on human ABO genes and is highly specific and sensitive when using limited and degraded DNA.

E-6087 is the most advanced compound among the cyclooxygenase-2 (COX-2) inhibitor drugs developed in our company. Its activity is mainly associated with the S(-)-enantiomer (E-6232), whereas the R(-)-enantiomer (E-6231) becomes an impurity whose content should be determined. Five main impurities and degradation products of E-6232 have been found (E-6144, E-6024, E-6072, E-6397 and E-6132), and some of them co-elute with the distomer when using a chiral high-performance liquid chromatography (HPLC) method. Consequently, we have optimized the separation of all the impurities from the two enantiomers of E-6087 by capillary electrophoresis (CE), in order to use the method for the enantiomeric purity determination of E-6232. The effect of the methanol (MeOH) content in the background electrolyte (BGE), the sulfobutyl ether-beta-cyclodextrin (SBE-beta-CD) and heptakis-(2,6-di-O-methyl)-beta-cyclodextrin (DM-beta-CD) concentration, and the capillary temperature have been studied. Separation of all compounds could be achieved in different systems, either in a single CD-system (with SBE-beta-CD) or in a dual CD-system (with DM-beta-CD as a neutral CD). By using the dual CD system a limit of detection (LOD) and a limit of quantitation (LOQ) of 0.03% and 0.1% of distomer, respectively, were achieved*.

A capillary electrophoresis method was developed for the enantioseparation of three novel cyclooxygenase-2 (COX-2) inhibitor drugs (E-6259, E-6036 and E-6087) with anti-inflammatory and analgesic activities using sulfobutyl ether-beta-cyclodextrin (SBE-beta-CD) as a chiral selector. The use of 50 mM sodium tetraborate at pH 9.2 with 30% v/v methanol, containing 7.1 mM SBE-beta-CD, as a background electrolyte (BGE) allowed the complete enantioseparation of the three neutral racemic mixtures (resolution = 2.4, 3.0 and 8.7, respectively) and their corresponding metabolites (oxidation products) in a single run. Migration times were shortened with some loss of enantioresolution by adding 1.75 mM dimethyl-beta-cyclodextrin (DM-beta-CD) to the previous BGE (dual CD system). The reversal of the migration order of E-6259 enantiomers in the dual CD system was also studied. Furthermore, the addition of DM-beta-CD to the BGE introduced a new chemoselectivity in the system that allowed E-6259 to be separated from the structurally similar compound E-6036.

We developed a head-space method for the determination of blood cyanide by gas chromatography with electron-capture detection. In this technique, a reaction precolumn packed with chloramine-T was used for the conversion of hydrogen cyanide into cyanogen chloride. Since the reaction precolumn eliminated the necessity of trapping hydrogen cyanide from biological samples, blood cyanide could be analyzed quickly by acidification only. Using this method, blood cyanide levels of fire victims were determined at autopsy. The serum values of cyanide ranged from 0.11 micrograms/ml to 18.12 micrograms/ml. However, a significantly higher cyanide content was detected in the left ventricular blood than in the right. This indicates that death was caused by the fire and suggests that the collecting point of the blood sample is an important factor in the determination of inhaled cyanide. There was a positive correlation between blood cyanide and carboxyhemoglobin contents.

We investigated the differences in the levels of carboxyhemoglobin (COHb), cyanide (HCN) and petroleum fuels (gasoline and kerosene) between left and right ventricular bloods from fire victims. COHb was slightly, and HCN and petroleum fuels were markedly higher levels in the left than those in the right. These effects were so called 'first pass phenomena' due to the circulation, diffusion and metabolization before the deaths of fire victims.

Two head-space gas chromatographic methods for the determination of hydrogen cyanide (HCN) in blood were demonstrated using electron capture detector (ECD). One was the double head-space gas sampling technique and the other used the reaction pre-column packed with Chloramine-T for the conversion of HCN into cyanogen chloride (CNC1). In the former method, HCN in blood was firstly released by acidification, and then the HCN gas was replaced into the another vial in which Chloramine-T solution had been placed. The head-space gas in the second vial was analyzed by gas chromatograph (GC). In the latter, HCN gas released was directly injected into the GC pre-connected the reaction column. The conversion of HCN into CNC1 was easily achieved by both methods. The use of dichloromethane as an internal standard and PTFE-faced septum for the sealing of vial greatly improved the precision and reliability of these analytical methods. The calibration curves by these methods gave good linearity and the lower detection limit taken from these plots was ca. 0.05 micrograms/ml. In particular, the reaction pre-column method, by which blood cyanide can be analyzed rapidly and accurately with only simple alteration of apparatus, is superior in the routine analysis of blood cyanide.

A method of gas chromatography-chemical ionization selected ion monitoring (GC-CI-SIM) is described for the determination of cocaine, benzoylecgonine and ecgonine methyl ester in biological materials using an Extrelut extraction technique. Recoveries of cocaine, benzoylecgonine and ecgonine methyl ester by this technique were 95, 81 and 97%, respectively. The method uses cocaine-d5, benzoylecgonine-d5 and lidocaine as internal standards, and isobutane as reagent gas for chemical ionization. Sensitivity of the method proved to be 1 ng/ml for cocaine and benzoylecgonine, and 10 ng/ml for ecgonine methyl ester when used in a 10-ml urine sample. With animal experiments, ecgonine methyl ester as well as benzoylecgonine was confirmed as a major metabolite of cocaine.

Changes of plasma lipids (triglyceride, TG: total cholesterol, Cho; and phospholipids, PL), free fatty acid (FFA), and blood glucose (BG) were studied in male rabbits after toluene administration (0.5 g/kg per os). Hypertriglyceridemia was observed at and after 2 h. Plasma FFA and BG were elevated temporarily during the early stage and lowered gradually thereafter. Initially, plasma Cho and PL were virtually unchanged, but the Cho level increased slowly after 6 h. The hypertriglyceridemia observed may have some adverse effects on heart function.

A method is described for the determination of delta 9-tetrahydrocannabinol (delta 9-THC) in the saliva by the use of a combination of moving-precolumn injector and glass capillary gas chromatograph with electron capture detector (GC/ECD). There were no interfering peaks due to impurities around the peak of pentafluoropropyl derivative of delta 9-THC (delta 9-THC-PFP). This GC/ECD method was linear over the range of 5-200 ng/ml of delta 9-THC-PFP. The lower detection limit was approximately 1 ng/ml. delta 9-THC content in the saliva after experimental marihuana smoking was measured by this method. It was demonstrated that for at least 4 h after smoking the level of delta 9-THC was sufficient for detection.

We developed a head-space method for the determination of blood cyanide by gas chromatography with electron-capture detection. In this technique, a reaction pre-column, packed with chloramine-T, was used for the conversion of hydrogen cyanide into cyanogen chloride. Since the reaction pre-column eliminated the necessity for trapping hydrogen cyanide from the biological samples, blood cyanide was quickly analysed by acidification only. The reaction pre-column was durable for at least several months. The calibration curve gave good linearity when dichloromethane was used as the internal standard, and the lower detection limit taken from this plot was ca. 0.05 micrograms/ml. The relative standard deviation of spiked blood samples was in the range 0.6-3.9%. We determined blood cyanide levels at autopsy in victims who had died from fire using this method. A significantly higher cyanide content was detected in the left ventricular blood than in the right. There was a positive correlation between blood cyanide and carboxylhaemoglobin contents. This simple and sensitive technique could be very useful for the determination of cyanide in various samples.

Characteristics of cytochrome oxidase prepared from hearts of Sprague-Dawley male rats were studied with the use of the fourth derivative spectrophotometry in respect to the cytotoxic effects of carbon monoxide (CO). CO-exposed rats tended to show lower specific activities of cytochrome oxidase than control and recovered rats. Moreover, there was a significant difference in the fourth derivative spectral features of the enzyme: CO-exposed groups indicated peaks at 412 nm in the spectra while controls at 408 nm. This spectral difference seemed to reflect specific effect of CO on cytochrome oxidase, though such trace remained for not more than a day after death.

Urine samples were collected before breakfast from 94 normal volunteers (41 males and 53 females) aged 25-70 years. Salsolinol (SA) was analyzed by gas chromatography-mass spectrometry (GC/MS), and dopamine, norepinephrine and epinephrine were determined using high performance liquid chromatography (HPLC). SA levels were significantly higher in the urine of male moderate drinkers (MDs) than in male seldom or non drinkers (SNDs). In females, however, a significant difference of urinary SA levels was not observed between MDs and SNDs. There was a sex difference of urinary SA levels among SND subjects, i.e., females showed a higher SA than males. Urinary catecholamines were not significantly altered by long-term moderate alcohol drinking in either sex. There was no correlation between urinary levels of dopamine and SA. These results indicate that urinary SA can be increased by long-term drinking even in normal, not alcoholic subjects.