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S Ameno

Publications and source records attributed to S Ameno.

At least 19 recordsLinked to original sources
PubMed2006

Changes in cholinergic function in the frontal cortex and hippocampus of rat exposed to ethanol and acetaldehyde.

Our previous microdialysis study demonstrated that both ethanol (EtOH) and acetaldehyde (ACe) decrease in vivo acetylcholine (ACh) release in the medial frontal cortex of freely moving rats. To better understand the mechanisms of EtOH and ACe's effects on the cholinergic system in the brain, choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) expression was examined at 40 and 240 min after a dose of EtOH (1 g/kg) in the rat frontal cortex and hippocampus. The control group was treated with 0.9% saline, and other groups received EtOH or cyanamide (CY, 50 mg/kg, a potent aldehyde dehydrogenase inhibitor) and 60 min later by EtOH intraperitoneally. Reverse-transcription polymerase chain reaction (RT-PCR) analysis revealed that ChAT mRNA levels were decreased by 72.8% and 71.6% in the EtOH and CY+EtOH groups, respectively, at 40 min after EtOH injection compared with saline in the frontal cortex. The hippocampal ChAT levels were reduced by 76.5% and 53.0% in the EtOH and CY+EtOH groups, respectively, at this time. CY+EtOH-induced depletion in ChAT mRNA levels was markedly higher than EtOH in the hippocampus. A similar decrease pattern of ChAT was observed at protein levels as determined by Western blot, but the reduced ChAT levels were significantly higher in the CY+EtOH group as compared with the EtOH group both in the frontal cortex and hippocampus. At 240 min after EtOH injection, the EtOH group had no effect on ChAT at mRNA levels, as compared with saline, whereas CY+EtOH group induced a significant decrease in ChAT mRNA expression to 62.0% and 65.5% in the frontal cortex and hippocampus, respectively. These data were consistent with the results of the Western blot analysis. AChE expression at mRNA levels was not changed at either 40 or 240 min after EtOH dosing in either of these groups in the frontal cortex and hippocampus. Within 40 and 240 min, a statistically significant difference in ChAT expression at mRNA and protein levels was found in the EtOH and CY+EtOH groups both in the frontal cortex and hippocampus. The data obtained from this study demonstrate that EtOH and ACe concentrations decreased ChAT expression at 40 and 240 min after EtOH administration in the frontal cortex and hippocampus, and this result suggests that reduced ChAT expression is strongly related to a decrease in ACh release in the rat brain.

Acetaldehyde↗
PubMed2002

Effects of whole deletion of CYP2A6 on nicotine metabolism in humans.

We investigated the effects of CYP2A6 genotypes on nicotine metabolism, focused from nicotine to cotinine and its additional 3'-hydroxylating resulted in trans-3'-hydroxycotinine formation. In the subjects genotyped by PCR-RFLP method, one cigarette smoking experiment was performed and urine samples were collected for 24 h. In all subjects who smoked, we detected nicotine, cotinine and trans-3'-hydroxycotinine in urine by GC-MS analysis. In whole deletion of CYP2A6, urinary excretion amounts of cotinine and trans-3'-hydroxycotinine were significantly smaller than those in the wild-type of CYP2A6*1. A lack of CYP2A6 reduces the formation of cotinine and trans-3'-hydroxycotinine, but not entirely reduces the trans-3'-hydroxycotinine formation. Unknown cotinine 3'-hydroxylating activity except CYP2A6 are suspected in humans.

Aryl Hydrocarbon Hydroxylases↗
PubMed2001

Blood carbofuran concentrations in suicidal ingestion cases.

We describe four fatal cases due to ingestion of carbofuran, a carbamate insecticide. Carbofuran was detected in the gastric contents using thin layer chromatography (TLC) and gas chromatography/mass spectrophotometry (GC/MS), and quantified in the blood using a gas chromatograph equipped with nitrogen-phosphorus detector (NPD). Fatal concentrations of carbofuran in blood ranged from 0.32 to 11.6 microg/ml.

Adult↗
PubMed2001

Lewis and Secretor gene effects on Lewis antigen and postnatal development of Lewis blood type.

Lewis (Le) and Secretor (Se) gene effects on postnatal change in Lewis antigens are described based on the quantitative analysis of Lewis antigens in blood. Genuine Lewis blood types were determined by Le and Se genotyping in DNA samples obtained from umbilical cord blood and infant blood. Lewis(a) (Le(a)) and Lewis(b) (Le(b)) antigen levels were measured by a time-resolved fluoroimmunoassay. We found that Lewis phenotypes in infants over 9 months of age agreed with the genuine types. In cord blood, the dosage effect of the Se gene on antigen levels was observed, but the Le gene effect was not observed. Both Se and Le gene effects were observed in newborn babies' blood 3-6 days after birth.

Aging↗
PubMed2001

Lack of association between smoking and CYP2A6 gene polymorphisms in A Japanese population.

This study determined the genotypes of the CYP2A6 gene in 96 smokers and 141 non-smokers in a Japanese population. The frequencies of wild-type of the CYP2A6* 1 and those with a whole deletion of the CYP2A6 gene were 93 (96.9%) and 3 (3.1%) in 96 smokers, and 134 (95.0%) and 7 (5.0%) in non-smokers, respectively. In addition, neither the CYP2A6* 2 nor CYP2A6* 3 alleles were observed in the population studied. There were no significant differences in the CYP2A6 genotype frequencies between smokers and non-smokers, as well as in the number of cigarettes smoked and the nicotine amounts inhaled per day between the CYP2A6* 1 and the deletion of CYP2A6. These results suggest that either the deletion or non-deletion of the CYP2A6 gene shows no significant effect on smoking behavior for the Japanese population examined.

Adult↗
PubMed2000

Hypothalamo-pituitary-adrenal axis activation by administration of cyanamide: a potent inhibitor of aldehyde dehydrogenase.

In this report, we investigated the effects of cyanamide (a potent inhibitor of aldehyde dehydrogenase (ALDH: EC 1.2.1.3)) on hypothalamo-pituitary adrenal (HPA)-axis using in situ hybridization histochemistry and radioimmunoassay. Cyanamide administration resulted in a dose-dependent increase in plasma corticosterone concentrations, significant increases in not only corticotrophin releasing factor (CRF) mRNA, but also arginine vasopressin (AVP) mRNA in the paraventricular nucleus (PVN) and proopiomelanocortin (POMC) mRNA in the anterior pituitary. These results suggest that cyanamide is able to activate the HPA axis at all levels of the axis.

Aldehyde Dehydrogenase↗
PubMed2000

Different phenotypes of multiple endocrine neoplasia type 1 (MEN1) in monozygotic twins found in a Japanese MEN1 family with MEN1 gene mutation.

We report monozygotic twins who showed different MEN1 phenotypes. The proband (28 y.o., female) had both primary hyperparathyroidism (PHP) and insulinoma, and genetic analysis revealed a point mutation (569del1, exon 3) of the MEN1 gene. This mutation causes a frameshift and produces a stop codon at codon 184. Restriction digestion (HinfI) analysis confirmed the same mutation of the MEN1 gene in six of the affected members including her two sisters, the monozygotic twins, and no such mutation in two unaffected members. In two generations of this family, eight of eleven family members had PHP and four of them were found to have other MEN1-related lesions. Both of the monozygotic twins had PHP. Interestingly, one had pancreatic tumor but the other had no evidence of it. Pituitary MRI showed no pituitary lesion in either of them. This is the first Japanese case of monozygotic twins with different MEN1 phenotypes.

Adult↗
PubMed1999

Acute fatal poisoning cases due to furathiocarb ingestion.

Seven cases involving acute fatalities due to ingestion of furathiocarb, a carbamate insecticide, are presented. Furathiocarb was detected in the gastric contents using thin layer chromatography (TLC) and gas chromatography/mass spectrophotometry (GC/MS), and quantified in the blood using a gas chromatograph equipped with a nitrogen-phosphorus detector (NPD). The fatal levels of furathiocarb in the blood ranged from 0.1 to 21.6 micrograms/ml.

Acute Disease↗
PubMed1999

Levels of paraquat in fatal intoxications.

We describe here fatal levels of paraquat in plasma of victims due to the ingestion of the herbicide, paraquat, and the relationship between those levels and survival times after ingestion. We determined paraquat levels in plasma of 106 paraquat poisoning cases in Korea between June 1992 and December 1996 using a visible spectrophotometric method based on the alkali-dithionite reaction. Among 55 cases with known survival times, plasma paraquat levels of victims who died within one day of ingestion ranged from 2.3 to 636.6 microg/ml (average 127.6 microg/ml) while those of the victims who died between 1 approximately 4 days ranged from 0.9 to 25.1 microg/ml (average 7.0 microg/ml). Since preparations containing 24.5% paraquat dichloride are still used in Korea, our data for Korean victims who died within one day were 8.5 times higher than those in Baselt and Cravey's report for the same survival times. Our data also suggest that victims in whom a plasma paraquat concentration of more than 30 microg/ml was detected are likely to have died within 24 h after ingestion.

Adolescent↗
PubMed1999

Forensic toxicological implication of acute fatal poisoning cases due to benfuracarb ingestion.

We describe here three cases involving acute fatalities due to benfuracarb ingestion and the forensic toxicological implications. Benfuracarb, a carbamate insecticide and its main metabolite carbofuran, were detected using thin layer chromatography (TLC) and gas chromatography/mass spectrophotometry (GC/MS) after extraction with ethyl acetate and then quantified using gas chromatography (GC) equipped with NPD. The blood levels of benfuracarb and carbofuran were in the range of 0.30-2.32 microg/ml and 1.45-1.47 microg/ml, respectively. Benfuracarb was not detected in urine, but carbofuran was detected in the range of 0.53-2.66 microg/ml.

Adult↗
PubMed1998

Combined toxicity of methanol and formic acid: two cases of methanol poisoning.

Two fatalities caused by methanol ingestion are presented. Quantitative analysis of methanol and formic acid using head-space gas chromatography showed concentrations of methanol and formic acid in the femoral blood of each subject of 2.19 mg/ml and 0.41 mg/ml, and 1.96 mg/ml and 0.38 mg/ml, respectively. We concluded that death was due to methanol ingestion and the mechanism causing death involved the combined effects of the anesthetic action of methanol itself and metabolic acidosis by formic acid. Forensic toxicokinetic analysis indicated that both victims had ingested about 100 g of methanol or more.

Adult↗
PubMed1998

Relationship between alcoholism and CYP2E1 C/D polymorphism.

The genotypes of the CYP2E1 loci of 35 alcoholic and 130 nonalcoholic (healthy controls) Japanese were investigated to determine the relationship between CYP2E1 (C/D) polymorphism and susceptibility to alcohol dependence. There was a significant (d.f. = 1, chi2 = 11.0, p < 0.001) difference in the CYP2E1 C gene frequency between alcohol dependents (0.41) and controls (0.28), suggesting that the C gene of CYP2E1 may be related to the risk of developing alcoholism in Japanese, whereas the frequency of the D gene was higher among controls than alcoholics. Healthy Japanese controls showed a significantly (d.f. = 1, chi2 = 30.1, p < 0.001) higher frequency of the C allele than Swedish healthy controls (0. 10) did.

Adult↗
PubMed1997

Lewis genotyping by the PCR-RFLP method in a Japanese population and its evaluation in forensic analysis.

Lewis phenotyping of red blood cells has many problems such as the influence of many biological conditions, the change during the period from newborn to early childhood and mistyping by non-specific anti-Lewis antibodies. Therefore, it would be useful to determine the Lewis genotype. Recently a method of Le-genotyping by PCR-RFLP was established. We determined the frequencies of Lewis genotypes in a Japanese population and discuss the applicability to paternity tests and other forensic applications. The gene frequencies of Le, le1 and le2 in the Japanese population studied were 0.7032, 0.2358 and 0.0610 respectively. Out of 12 paternity cases where paternity was excluded by other markers, 3 alleged fathers could also be excluded by Lewis genotyping. The genotype from organs of a fetus from a 3-month pregnancy was Le/Le. The determination of Lewis genotypes could play a useful role as a genetic marker in paternity tests and forensic analyses.

Asian People↗
PubMed1997

[Relationship between alcoholism and CYP2E1 genotypes].

The genotype of the CYP2E1 loci in 36 alcoholic and 42 non-alcoholic (healthy) Japanese were investigated to examine the relationship between the polymorphisms of CYP2E1 (C/D) and the susceptibility to alcohol dependence. There was a significant (df = 1, chi 2 = 4.39, p < 0.05) difference in CYP2E1 CD (heterozygote) genotype frequency between alcohol dependents (56%) and controls (33%), suggesting that the CD (heterozygote) genotype of CYP2E1 may have something to the risk of developing alcoholism in Japanese, whereas DD (homozygote) genotype was high among controls.

Adult↗
PubMed1997

Forced double suicide by fire revealed by autopsy and toxicological examination: a case report.

We report here a forced double suicide by fire. Two burned bodies discovered in the debris of a house fire were identified as a father and his son by odontological findings. In the father, the concentration of carboxyhemoglobin (CO-Hb) in the left ventricle was over 90% and endrin, an organochlorine pesticide, was also detected in the stomach contents. However, 30.5% of CO-Hb in left ventricular blood and gasoline traces from an intratracheal puncture were detected in the son who had been undergoing treatment at a neuropsychiatric clinic. From these results, we determined this case to be a double suicide forced by the father in which the father set a fire with gasoline, thus burning his son to death, and then died in the fire himself after ingestion of Endrin. This case suggests the importance of integration of the results from the detailed forensic pathological and toxicological examinations and the scene investigation.

Adult↗
PubMed1996

Application of capillary gel electrophoresis to the diagnosis of the aldehyde dehydrogenase 2 genotype.

This study dealt with the application of capillary gel electrophoresis (CGE) to diagnosis of the aldehyde dehydrogenase 2 (ALDH-2) genotype. Electrophoresis was performed on a low cross-linked polyacrylamide gel ¿3% T [g acrylamide+g Bis (N,N'-methylenebisacrylamide)], 0.5% C (g Bis/% T)¿ in 100 mM Tris-borate buffer (pH 8.3) at -10 kV with on-column UV detection (260 nm). During the PCR reaction, DNA from the wild-type allele generated a MboII restriction site, which is an amplification created restriction site. This did not occur, however, with DNA fragments from the mutant allele. Therefore, determination of the heterozygous genotype, the coexistence of wild-type and mutant alleles, was easily possible. Analysis of the MboII restriction digests of the PCR products was completed in less than 20 min, showing two peaks corresponding to fragments of 125 (cleaved) and 135 (uncleaved) base pairs (bp), respectively. On the other hand, determination of the homozygous genotype, wild-type or mutant, was difficult in one electrophoresis run. The CGE of the MboII restriction digests gave a single peak and the identification, cleaved or uncleaved, was difficult under our experimental conditions. However, the addition of aliquots of the PCR reaction mixture to the restriction digests, followed by re-electrophoresis, allowed successful diagnosis, yielding two peaks (cleaved and uncleaved) for the wild-type and one peak (uncleaved) for the mutant allele. This study demonstrated that CGE offers a high-speed, high-resolution analytical tool for determining genetic types, as compared with the conventional slab gel methodologies.

Aldehyde Dehydrogenase↗
PubMed1996

Detection of two metabolites of diquat in urine and serum of poisoned patients after ingestion of a combined herbicide of paraquat and diquat.

This report describes the identification of diquat-dipyridone and diquat-monopyridone as metabolites of diquat, and time course changes of these metabolites plus diquat and paraquat in urine and serum of three poisoned patients who ingested the combination herbicide Preeglox L (containing 5% paraquat dichloride and 7% diquat dibromide) in a suicide attempt. Diquat-dipyridone was isolated from urine and identified by electron impact mass spectrometry, thin layer chromatography and high performance liquid chromatography (HPLC). Diquat-monopyridone, diquat-dipyridone, diquat and paraquat in serum and urine were assayed by HPLC with fluorescence and UV detection. Paraquat-monopyridone as a metabolite of paraquat was not detected in any samples. These results indicate that diquat is metabolized to diquat-monopyridone and diquat-dipyridone and also that the metabolism of diquat is easier than that of paraquat in humans. The concentrations of each metabolite were always lower than that of diquat in each specimen. However, the ratios of the concentration of each metabolite against the concentration of diquat increased with the decrease of diquat concentration. The metabolism of diquat seems to lower slightly the diquat concentration.

Chromatography, High Pressure Liquid↗