Rapid uranium preconcentration and separation method from fresh water samples for total U and 235U/238U isotope ratio measurements by ICP-MS.

A simple and rapid method using TRU resin cartridges (Eichrom Technologies, Inc., USA) and quadrupole ICP-MS for total uranium (U) and 235U/238U isotope ratio measurements in fresh water samples was investigated. After U extraction on the resin by sample solution loading, three alkaline reagents, tetramethyl ammonium hydroxide (TMAH), NaOH and NH4OH were studied for U elution behavior from the resin cartridges and applicability of these eluates was evaluated with respect to direct introduction to ICP-MS. Among the studied eluants, TMAH showed the best results with high U recovery and no counting interferences with internal standard elements such as thallium and bismuth. Moreover, U in water samples was separated from many major and minor elements with the TRU cartridges. Almost all U was concentrated in 10 mL of 0.014 M TMAH in 2 h using 200 mL of water sample.

Soybean isoflavones inhibit estrogen-stimulated gene expression in mouse uteri.

This study was performed to examine the inhibitory effects of soybean isoflavones on estrogen-stimulated gene expression of the uteri in ovarectomized mice. Especially when compared with the inhibitory effect of genistein and daidzein as aglycosides described in our previous report, subcutaneous administration of the glycoside genistin significantly decreased the levels of estradiol-17beta (E2)-induced expressions of c-jun, interleukin (IL)-1alpha and tumor necrosis factor (TNF)-alpha mRNAs (p < 0.005, p < 0.05 and p < 0.05, respectively) and seemingly proteins in the mice uteri, whereas the glycoside daidzin weakly inhibited E2-stimulated expressions of c-fos and IL-1alpha. Both genistin and daidzin seemed to have a weaker inhibitory effect than that of genistein and daidzein on the expression of estrogen-stimulated genes. It is suggested that those glycosides are naturally derived and generally absorbed from plant foods and might prevent E2-related endometrial carcinogenesis.

Use of TEVA resin for the determination of U isotopes in water samples by Q-ICP-MS.

In order to measure uranium isotopic mass ratio in natural water samples by Q-ICP-MS, an application of TEVA resin (Eichrom) was studied to separate and concentrate U. After being evaporated to dryness, the sample residue was dissolved in 6 M HCl, then, TEVA extraction was carried out. U extracted on the resin could be removed with 20 ml of 1 M HCl (U fraction) when Fe content was lower than 2 mg. U recovery in U fraction showed a negative correlation with Fe content in the samples.

Preventive effects of Juzen-taiho-to on N-methyl-N-nitrosourea and estradiol-17beta-induced endometrial carcinogenesis in mice.

Two experiments were conducted to determine effects of Juzen-taiho-to on endometrial carcinogenesis in mice. In the first experiment, Juzen-taiho-to treatment (2 weeks) decreased the levels of estradiol-17beta (E(2))-stimulated expression of c-fos/jun mRNA and their oncoproteins, determined by reverse transcription-polymerase chain reaction and Southern blot analysis, and the immunohistochemical method, in the uteri of ovarectomized mice. For the second experiment, 93 female ICR mice were given N-methyl-N-nitrosourea (MNU) solution (1 mg/100 g body weight) and normal saline (as controls) into their left and right uterine corpora, respectively, and were divided into four groups. Group 1 was given a diet containing 0.2% Juzen-taiho-to and 5 p.p.m. E(2). Group 2 was given a diet containing 5 p.p.m. E(2) alone. Group 3 was given a diet containing 0.2% Juzen-taiho-to alone. Group 4 was kept on the basal diet alone and treated as a control. Juzen-taiho-to treatment significantly decreased incidences of the uterine endometrial atypical (P<0.01), complex (P<0.05) and simple hyperplasias (P<0.01), under estrogenic stimulation. It is suggested that Juzen-taiho-to has an inhibitory effect on E2-related endometrial carcinogenesis in mice, relevantly through suppression of estrogen-induced c-fos/jun-expression.

Contributions of 18 food categories to intakes of 232Th and 238U in Japan.

Daily intakes of 232Th and 238U and contributions of food categories to those nuclide intakes in Japanese were estimated using a market basket study for 18 food categories. Food categories having higher 238U contents (per g-fresh) were found to be as follows: seaweeds 1,140 microBq; fishes and shellfishes 37 microBq; nuts and seeds 11 microBq; bean products 8.6 microBq; and cooked meals 7.3 microBq. Big contributors to the daily 238U intake in Japan were as follows: seaweeds (50%); fishes and shellfishes (26%); and bean products (4.3%). For 232Th, higher contents (per g-fresh) were found as follows: seaweeds 28 microBq; fishes and shellfishes 13 microBq; nuts and seeds 8.2 microBq; green vegetables 3.9 microBq; cooked meals 3.5 microBq; and bean products 2.9 microBq. Big contributors to the daily 232Th intake were as follows: fishes and shellfishes (44%); green vegetables (11%); bean products (7.4%); and seaweeds (6.0%). For both nuclides, marine food products were big contributors, while minor contributors were oil and fats, eggs, and cooked meals. Daily intakes of 232Th and 238U in Japan were estimated to be 2.7 mBq and 14 mBq per person from the intakes of the 18 categories, respectively. Annual effective doses were estimated to be 232Th, 2.2 x 10(-7) Sv, and 238U, 2.2 x 10(-7) Sv.

Daily intakes of 134Cs, 137Cs, 40K, 232Th, and 238U in Ukrainian adult males.

Total diet samples were collected to estimate dietary intakes of several radionuclides for Ukrainian males by duplicate portion studies. The samples were collected in the Kiev, Rovno and Volynsky regions in autumn of 1994. Some foodstuffs, including milk and potato, were also collected in the same regions. Daily intakes of 232Th and 238U were estimated to be 2.0 mBq and 7.5 mBq per person, respectively. The estimated daily intake of 40K, 85 Bq per person, was equivalent to that of Reference Man (the intake of a West European and a North American). Daily intakes of 137Cs were found to be quite different between some regions. Daily intakes were 1.8 Bq per person in the Kiev region and 12 Bq per person in the Rovno and Volynsky regions. Daily intake of 134Cs was below 1 Bq per person.