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This study examined paroxysmal abnormalities and epilepsy in EEG for individuals with pervasive developmental disorders (PDD) in two parts: first with a large number of subjects (n=1624); and second with extracted subjects followed from 5 years into adolescence and beyond (n=92). Many paroxysms in PDD patients in their childhood tended to appear at various sites and the same held for paroxysms at the time of epilepsy onset. However, in adolescence and beyond, paroxysms in the frontal region prevailed as those appearing at sites other than the frontal region tended to disappear. The same held for paroxysms at the time of epilepsy onset. These paroxysms in the frontal area characteristic of PDD were named "Paroxysms at F." It was suggested that functional abnormality in the frontal region exists in PDD through paroxysmal EEG abnormalities and epilepsy.

Carbon monoxide (CO) treatment of fish meat of tuna, yellowtail, tilapia etc. is not allowed in Japan, since it can maintain the red color for a longer period than the microbiological shelf life of fish meat. The official method for quantification of CO has a problem, in that a part of the CO is lost during the preparation of the fish sample. To solve this problem, we modified the official method in this study. We also applied this modified method to survey the contents of CO in tuna, yellowtail, young yellowtail, and tilapia. As a result, the modified method was found to be more suitable for CO quantification than the official method. An inter-laboratory study by 4 laboratories confirmed that the CO content of many samples of tilapia exceeded the regulation value, apparently due to the higher recovery of CO, compared to the official method. Therefore, it was suggested that the regulation value in the case of tilapia should be changed if this method is introduced as an official method.

An analytical method for residual sodium chlorite in several kinds of processed herring roe treated with sodium chlorite was studied. Sodium chlorite was extracted with 9 mmol/L sodium carbonate. After centrifugation, the supernatant was filtered through a 0.2 microm nylon filter. The filtrate was deproteinized by ultrafiltration and chloride ion was removed with an On-Guard Ag cartridge column. The eluate was subjected to conductivity detector-ion chromatography. Recoveries of sodium chlorite from herring roe spiked at the level of 5 mg/kg were 88 +/- 3.7% (n = 5, CV 4.2%). The method had a quantitation limit of 5 mg/kg for processed herring roes.

A sensitive method for detecting bromate in bread by ion chromatography with inductively-coupled plasma mass spectrometry (IC/ICP-MS) was developed. Bromate was extracted from bread with water. The clean-up procedure included a 0.2 micron filter, a C18 cartridge for defatting, a silver cartridge to remove halogen anions, a centrifugal ultrafiltration unit to remove proteins, and a cation-exchange cartridge to remove silver ions. A 500 microL sample solution was applied to IC/ICP-MS. The detection limit and the quantitation limit of bromate in the solution were 0.3 ng/mL and 1.0 ng/mL, expressed as HBrO3, respectively, which corresponded to 2 ng/g and 5 ng/g, respectively, in bread. Recovery of bromate was about 90%, and the CV was about 2%. Based on the detection limit in solution and recovery from bread, the detection limit of bromate in bread was estimated to be 2 ng/g.

An unknown red pigment was purified from an apple syrup product imported from Canada, using a DIAION HP-20 column with methanol as the eluent. By spectroscopic means and chemical synthesis, the isolated pigment was identified as 4-aminocarminic acid, which is the major pigment of acid-stable carmine (a red colorant illegal in Japan). In addition, HPLC and TLC methods were proposed to detect this illegal colorant. While the color of carminic acid changed from yellow to red in the pH range of McIlvaine buffer (3.0-7.0), the color of 4-aminocarminic acid was always red, and also the ultraviolet/visible (UV/Vis) spectra did not change. These characteristics are useful to distinguish 4-aminocarminic acid from carminic acid.

Acid-stable carmine has recently been distributed in the U.S. market because of its good acid stability, but it is not permitted in Japan. We analyzed and determined the structure of the major pigment in acid-stable carmine, in order to establish an analytical method for it. Carminic acid was transformed into a different type of pigment, named acid-stable carmine, through amination when heated in ammonia solution. The features of the structure were clarified using a model compound, purpurin, in which the orientation of hydroxyl groups on the A ring of the anthraquinone skeleton is the same as that of carminic acid. By spectroscopic means and the synthesis of acid-stable carmine and purpurin derivatives, the structure of the major pigment in acid-stable carmine was established as 4-aminocarminic acid, a novel compound.

The mean concentrations and daily intake of four antifungal agents were estimated based on the results of an analysis of 7,005 samples of food obtained in official inspections by Japanese local governments in fiscal year 1998. The mean concentration of diphenyl was 0.0004% of the allowable limit, and those of imazalil, o-phenylphenol, and thiabendazole were 14.0%, 3.5%, and 5.7%, respectively. The daily intakes of these antifungal agents per person, estimated from their concentrations and the daily consumption of the foods, were 0.000326, 1.89, 11.5, and 23.3 micrograms, respectively, and assuming a body weight of 50 kg, the amounts of these antifungal agents consumed were 0.000013%, 0.15%, 0.12%, and 0.47% of the acceptable daily intake, respectively. These values are similar to the values obtained on the basis of the results of the official inspection in fiscal years 1994 and 1996, except that the amount of diphenyl is much lower (1/100).

A mutagenic anthraquinone, lucidin (1), occurring in Rubiaceae plants, reacted with nucleic bases under physiological conditions to form adducts. The order of the reactivity is as follows: adenine > guanine >> pyrimidine bases approximately 0. By spectroscopic analyses, the isolated purine base adducts were identified as condensed reactants at the benzylic position of 1 with a nitrogen atom of a purine base. The results indicate a strong possibility of the formation of an exomethylenic compound as an electrophile intermediate.

Twenty compounds were isolated from the roots of Rubia tinctorum which are used as a commercial source of madder color. Among these compounds, mollugin (1), 1-hydroxy-2-methylanthraquinone (2), 2-ethoxymethylanthraquinone(11), rubiadin (13), 1,3-dihydroxyanthraqunone (14), 7-hydroxy-2-methylanthraquinone (16), lucidin (17), 1-methoxymethylanthraquinone (18) and lucidin-3-O-primeveroside (19) showed mutagenicity with Salmonella typhimurium TA 100 and/or TA 98. Since the mutagenic compounds isolated are anthraquinone derivatives with the exception of compound 1, structure-mutagenicity relationships of the anthraquinones were also studied. The results suggested that the greatest activity is exhibited by 1,3-dihydroxyanthraquinones possessing methyl or hydroxylmethyl group on carbon 2.

Mean concentration and daily intake of the inorganic food additives nitrite, nitrate, and sulfur dioxide were estimated based on the analysis of 15, 569 samples of food obtained at official inspections by Japanese local governments in fiscal year 1996. The mean concentration of nitrite was 17.2% of the allowable limit, and those of nitrate and sulfur dioxide were 30.9% and 14.4%, respectively. Daily intakes of these inorganic food additives per person, estimated from the concentrations and daily consumption of the foods, were 1.07, 1.43, and 1.45mg, respectively. These amounts of nitrite, nitrate, and sulfur dioxide were 35.7%, 0.8%, and 4.1% of the acceptable daily intakes (ADIs), respectively, when body weight was assumed to be 50kg. Ratios to ADI were similar to those based on the results of the official inspection in fiscal year 1994 except that nitrite intake in fiscal year 1994 was 10.6% of the ADI. The major reason for the increase of the calculated daily intake of nitrite in fiscal year 1996 was that 0.020g/kg nitrite, corresponding to a daily intake of 0.87mg, was found in confectionery, a food category which was not inspected in fiscal year 1994.

The mean concentration and daily intake of five preservatives were estimated based on the results of an analysis of 89,927 samples of food obtained in official inspections by Japanese local governments in fiscal year 1998. The mean concentration of benzoic acid was 9.5% of the allowable limit, and those of dehydroacetic acid, p-hydroxybenzoic acid, propionic acid, and sorbic acid were 1.5%, 5.7%, 1.7%, and 23.9%, respectively. Daily intake levels of these preservatives per person estimated from the concentration and daily consumption of foods were 6.23 mg, 0.0303 mg, 1.02 mg, 8.10 mg, and 25.0 mg, respectively, and assuming a body weight of 50 kg, the amounts of benzoic acid, p-hydroxybenzoic acid, and sorbic acid consumed were 2.5%, 0.2%, and 2.0% of their acceptable daily intakes, respectively. These values were similar to those obtained based on the results of the official inspections in fiscal years 1994 and 1996.

The mean concentration and daily intake of antifungal agents were estimated based on the results of the analysis of 6, 369 samples of food obtained at official inspections by Japanese local governments in fiscal year 1996. The mean concentration of diphenyl was 0.007% of the allowable limits, and those of imazalil, o-phenylphenol, and thiabendazole were 8.0%, 3.0% and 3.2%, respectively. Daily intakes of these four antifungal agents per person estimated from the concentrations and daily consumption of the analyzed foods were 0.0395, 11.1, 8.97 and 26.2μg, respectively, and assuming a body weight of 50kg, these amounts of these antifungal agents were 0.0016%, 0.89%, 0.090%, and 0.52%, respectively, of the acceptable daily intakes. These values were similar to those based on the results of the official inspection in fiscal year 1994, except that the amount of diphenyl was much smaller (1/50).

An analytical method for the determination of sodium alginate in various foods was developed. Pectin and protein were removed from foods with 1.5mol/L sulfuric acid and 1mol/L magnesium sulfate-2.2mol/L sodium sulfate solution. Pectic substances in foods were removed as a precipitate with 1% sodium hydrogen carbonate solution. Alginic acid in the extract was precipitated as a copper salt, dissolved in 1mol/L ammonia water, and determined colorimetrically by means of a naphthoresorcinol reaction. The described method was applied to 18 kinds of food. The recovery of sodium alginate spiked at the level of 0.1% was more than 75%, except for soybean flour. The determination limit of the method was 0.002%. Sodium alginate was not detected in 18 kinds of food, but was detected in whipped cream, pudding and noodles at levels of 0.280%, 0.112% and 0.290%, respectively.

Polyvinyl acetate (PVAc) has been used in many countries as a masticatory substance in chewing gum base. A method was developed for the determination of residual vinyl acetate monomer (VAcM) in PVAc for chewing gum base. PVAc (2.5g) was dissolved in toluene and the prepared solution was injected into a gas chromatograph equipped with a capillary column coated with DB-1 (0.32mm i. d.×30m, 5μm film thickness) and an FID. The calibration curve of VAcM showed a good linear correlation (r=0.9998) in the range of 0.19μg/mL-9.6μg/mL. The method was applied to determine VAcM in 12 PVAc samples for chewing gum base. Residual VAcM was found in 6 samples (3-12μg/g). In addition, acetic acid (a raw material) was detected in all samples, and isopropanol and ethyl actate, which are solvents used in the production, were detected in 10 samples.

A survey of the concentration of carbon monoxide (CO) in flesh from a variety of fish was conducted to see whether fish which had been exposed to CO gas could be detected. CO in fish flesh was obtained by head-space gas chromatography and determined after conversion of CO to methane with a methanizer. Concentrations of CO ranged from 3 to 12μg/kg fish flesh, showing a narrow range in each species of fish except tilapia (Tilapia mossambica). CO was high in the red-flesh fish and low in the white-flesh fish. CO in sliced tilapia (a species of white-flesh fish), however, ranged from 7 to 957μg/kg. In tilapia, a high concentration of CO was observed in a sample in which the blood-colored parts of the slice were bright red, whereas the CO concentration was low in a sample in which the blood-colored parts were dark brown.The CO concentration in sliced tilapia containing 8μg CO/kg increased to 234μg/kg when the slice was exposed to CO gas. The blood-colored parts of the slice became bright red after the exposure. CO in the homogenate prepared from the CO-exposed sample decreased to less than 50μg/kg within 4 days on storage in a refrigerator (5°C). The concentration of CO in the control increased slightly during this period. Among 19 commercial samples of tilapia, CO slightly increased in 5 samples containing about 10μg CO/kg and decreased in 14 samples containing more than 50μg CO/kg when the homogenate was kept at 5°C for 2 days. The blood-colored parts of the former group containing lower concentrations of CO were dark brown and those of the latter group containing higher concentrations of CO were bright red. The latter group of tilapia was suspected to have been exposed to CO gas.

An analytical method for madder color in foods by high performance liquid chromatography (HPLC) was developed. As reference/guide compounds for the analysis, ruberythric acid (1), lucidin-3-O-primeveroside (2), and alizarin (3) were selected, since they are the principle coloring constituents in the ethanol-water (1:1) extract of madder. Soft drink colored with madder extract was subjected to HP-20 (Diaion) ion-exchange column chromatography prior to the HPLC procedure. Recoveries of 1, 2, and 3 from the soft drink were 83, 85, and 100%, respectively. In the case of proteinaceous foods (kamaboko and lactic drink) colored with madder extract, the raw material (5g) was homogenized in water and the homogenate was heated at 85°C for 3 hours under an acidic condition (pH 2, adjusted with HCl) to extract the reference/guide compounds. After neutralization with NH4OH solution, the homogenate was purified by HP-20 column chromatography for HPLC. By the acid treatment, 1 and 2 were partially hydrolyzed to compounds 4 and 5. On the basis of the spectroscopic data, 4 and 5 were identified as alizarin-2-O-glucoside and lucidin-3-O-glucoside, respectively. The recoveries of 1, 2, and 3 were 68, 83 and 100% (kamaboko) and 71, 78, and 100% (lactic drink), respectively, taking into account the amounts of the hydrolyzed compounds.

Lymphocytes from four patients with NF and from four normal controls are studied for SCEs and the cell cycle kinetics in the MMC-treated cultures. The result reveals that NF lymphocytes have almost the same proliferative kinetics and SCE frequencies as normal cells both in untreated cultures and when exposed to MMC.

A sensitive and simple method for the separation and determination of secondary amines in foods by high performance liquid chromatography (HPLC) with a fluorescence detector is described.The secondary amines in a food sample were extracted with 0.05N hydrochloric acid. Amines in the extract were readily converted into the corresponding NBD-amines by reaction with 7-chloro-4-nitrobenzo-oxa-1, 3-diazole (NBD-chloride) under alkaline conditions. Eight amines were separated and determined on a Zorbax SIL column with cyclohexane and ethyl acetate (3:2) as the mobile phase.The limit of determination was 0.2ppm (dimethylamine, DMA). The recoveries of DMA added to cod roe, fish sausage and coocked herring were 100, 81 and 85%, respectively. It was observed that coocked food samples contained larger amounts of secondary amines than raw samples. White and black pepper contained large amounts of piperidine (510 and 250ppm, respectively).

A sensitive and simple separation method for methylguanidine (MG) and agmatine (AGM) in various foods by high performance liquid chromatography with a fluorescence detector is described. Food samples were homogenized in 4% trichloroacetic acid solution and filtered. The guanidino compounds were extracted with n-butanol from the filtrate under alkaline conditions and re-extracted with 1N hydrochloric acid. They were converted into fluorescent derivatives by reaction with benzoin under alkaline conditions. Guanidino compounds were separated and determined on a Nucleosil 5C18 column with methanol -0.5M Tris-Hydrochloric acid Buffer (pH 8.6) (8:2) as the mobile phase. The recoveries of MG and AGM added to smoked dried fish and wiener sausage were 85.0% (MG), 82.5% (AGM) and 88.2% (MG), 82.3% (AGM), respectively. The limits of determination were 0.1ppm for MG and 0.5ppm for AGM. Smoked-dried bonito (Katsuo-bushi) contained 12 to 238ppm of MG. The amounts of MG and AGM determined in almost all samples were small or below the detection limits.