Jun Ikebuchi

Distribution of Hp, Tf, Gc and Pi polymorphisms in a Nepalese population

Hp typing and Tf, Gc and Pi subtypings were performed on 144 serum samples from a Nepalese population in the Katmandu Valley, Nepal. The obtained allele frequencies are as follows: Hp1 = 0.1771, Hp2 = 0.8229; TfC1 = 0.7222, TfC2 = 0.2500, TfC3 = 0.0174, TfCnepal (TfC9) = 0.0104; Gc1F = 0.2448, Gc1S = 0.4825, Gc2 = 0.2727; PiM1 = 0.6076, PiM2 = 0.2118, PiM3 = 0.1806. The relationship between this sample population and the Indian population is discussed.

Orosomucoid (ORM) Typing by Isoelectric Focusing: Evidence for Several New Variants Including ORM1 and ORM2 Silent Alleles

Abstract. Human orosomucoid (ORM) is composed of two tightly linked loci, ORM1 and ORM2, located on chromosome 9q. Some haplotypes contain duplicated ORM1 or ORM2. The present study using isoelectric focusing has revealed seven ORM haplotypes including new variants and/or silent alleles detected in eight Japanese families. ORM1*5‐2‐ORM2*15 in combination with common ORM1*1‐ORM2*1 produced a five‐band pattern. ORM1*5‐ORM2*1 was observed in three families. ORM2*9 was coexistent with ORM1*1 or ORM1*2·1. ORM1*Q0 was linked to ORM2*1 or ORM2*14. ORM2*Q0 was suggested to be in association with ORM1*2. The ORM haplotypes with a silent gene must have arisen from unequal crossing‐over between the tandemly duplicated genes of ORM.

Evaluation of paraquat concentrations in paraquat poisoning

The toxicological significance of paraquat concentrations in paraquat poisonings was evaluated by means of multivariate analysis methods. Paraquat could be determined by a newly developed procedure, which involved thin-layer chromatography with flame ionization detector (TLC-FID) and solid-phase extraction with a disposable octadecylsilane cartridge. This new method proved to be simple, rapid and reliable for the analysis of paraquat in our seven cases of suicidal poisoning. The relationship between plasma paraquat concentration (C) and time from ingestion (T) could be best described by the following functions. The regression equation of fatal cases was ln[ln(Cx1000)]=2.5453-0.2114 lnT. The regression equation of survivors was ln[ln(Cx1000)] =2.1041-0.2826 lnT. The discriminant function (D) to separate the fatal and survival cases was D= 1.3114-0.1617 lnT−0.5408 [In(Cx1000)] (fatal cases: D<0, survivors: D>0). The discriminant function was demonstrated to have a high reliability for the toxicological significance in our seven poisoned patients. The significant correlation between plasma paraquat concentration and urine paraquat concentration (C) in our cases was obtained. The regression equation was lnC=0.953 lnC+1.409. This also indicated that urinary concentrations are 3.3–4.5 times greater than plasma concentrations. The multiple regression equation among plasma paraquat concentration, time from ingestion, and the ingested volume (V) of Gramoxone® (trade name of paraquat), was lnC=0.009V−0.232T+3.612.It is suggested that the determination of paraquat is of great value, and that these data are useful in assessing the severity and predicting the outcome of poisoning for forensic and clinical purposes.

Gas chromatographic and gas chromatographic-mass spectrometric determination of gasoline in a case of gasoline vapor and alcohol poisoning.

A case of fatal poisoning due to the combined effect of alcohol and gasoline following an automobile accident is described. Toxicological analyses by means of gas chromatography and gas chromatography-mass spectrometry permitted the identification and quantitation of alcohol and several hydrocarbons in the heart blood and in the gas in the lung. Great variation was found in the estimates of blood gasoline concentration, depending on which of six constituents of gasoline was chosen for quantitation. The cause of this variation is discussed, together with the possible mechanisms leading to death.

Orosomucoid (ORM) Typing by Isoelectric Focusing: An Analysis of ORM Haplotypes

A new separator isoelectric focusing method for typing of orosomucoid (ORM) was developed. This method provided a superior resolution of ORM patterns: two close bands of ORM1*5.2 products were clearly separated. A total of 364 subjects from Okinawa (Japan) were classified into 21 ORM phenotypes determined by 6 ORM1 and 7 ORM2 alleles including a polymorphic silent allele, ORM2*QO, and 2 new rare variants, ORM2*18 and ORM2*19. These phenotypes were also explained by 12 ORM haplotypes, half of which were polymorphic.

Phosphoglucomutase-1 Subtypes: Polymorphic Occurrence of PGM1*7+ and Geographical Variation in Japan

The distribution of gene frequencies in the phosphoglucomutase-1 (PGM1) system was investigated in two Japanese populations from Yamaguchi (Western Japan) and Okinawa (Southern Japan) using an improved isoelectric focusing method permitting the successful detection of the most anodal variant PGM1 3+. PGM1*7+ occurred with a polymorphic frequency of 0.012-0.021. A difference in the gene frequency was observed between the two populations. In comparison with neighboring populations, the Yamaguchi population was similar to Mongolians and Koreans in North China, and Okinawa to Zhuang in South China.

Presence of N-Methylated β-Carbolinium Ions and Potential Neurotoxic Analogs of MPP+ in the Brain and Cerebrospinal Fluid of Parkinsonian and Non-Parkinsonian Patients

The etiology of Parkinson’s disease is unknown. N-Methyl-4-phenyl-tetrahydropyridine (MPTP), a contaminant originally found in synthetic “street heroin”, induces Parkinsonian like symptoms which arise from destruction of nigrostriatal neurons.1 After crossing the blood-brain-barrier, MPTP is oxidized intracerebrally in glia or non-dopaminergic neurons by monoamineoxidase B to an intermediate, N-methyl-4-phenyl-dihydropyridium ion, which disproportionates or is spontaneously oxidized to N-methyl-4-phenyl-tetrahydropyridinium ion (MPP+).2–4 The “MPTP story” led to considerations that environmental and/or endogenously generated substances with similar structures to MPTP may undergo brain bioactivation to mitochondrial toxicants. Recent studies have concentrated on iso-quinolines5–9 and β-carbolines (BCs).