Soybean meal fermented by Aspergillus awamori increases the cytochrome P-450 content of the liver microsomes of mice

The effect of soybean meal fermented by Aspergillus awamori on the acute lethality of acetaldehyde, pentobarbital sleeping time, and cytochrome P-450 content of the hepatic microsomes was studied in mice. Most of the daidzin and genistin in soybean meal (SBM) were converted into the respective aglycones, daidzein and genistein, by fermentation. In experiment 1, mice were fed isonitrogenic test diets with one of the following five protein sources for 28 d: casein, SBM, fermented and hot-air-dried SBM (FSBM-HD), fermented and freeze-dried SBM (FSBM-FD), or methanol-extracted FSBM-FD (FSMB-FD-R). The acute lethality of acetaldehyde in mice fed the FSBM-FD diet was significantly lower than that in mice fed the SBM, FSBM-HD, or FSBM-FD-R diet. In experiments 2 and 3, mice were fed isonitrogenic test diets with one of the following four protein sources for 28 d: casein, SBM, FSBM-FD, and FSBM-FD-R. The pentobarbital sleeping time was significantly shorter and the cytochrome P-450 content was significantly higher in the mice fed the FSBM-FD diet than the respective value in mice fed the other test diets. In experiment 4, mice were fed one of eight diets which contained different levels of aglycone obtained by varying the proportion of FSBM-FD and FSBM-FD-R, for 28 d. The cytochrome P-450 content in hepatic microsomes increased as the dietary level of isoflavonoid aglycones increased, but there was a saturation phenomenon. These results suggest that soy isoflavonoid aglycones are more potent inducers of cytochrome P-450 than isoflavonoid glycosides.     

Neutron activation analysis of a particle returned from asteroid Itokawa

A single grain (~3 micrograms) returned by the Hayabusa spacecraft was analyzed by neutron activation analysis. This grain is mainly composed of olivine with minor amounts of plagioclase, troilite, and metal. Our results establish that the Itokawa sample has similar chemical characteristics (iron/scandium and nickel/cobalt ratios) to chondrites, confirming that this grain is extraterrestrial in origin and has primitive chemical compositions. Estimated iridium/nickel and iridium/cobalt ratios for metal in the Itokawa samples are about five times lower than CI carbonaceous chondrite values. A similar depletion of iridium was observed in chondrule metals of ordinary chondrites. These metals must have condensed from the nebular where refractory siderophile elements already condensed and were segregated.     

Oxygen isotopic compositions of asteroidal materials returned from Itokawa by the Hayabusa mission

Meteorite studies suggest that each solar system object has a unique oxygen isotopic composition. Chondrites, the most primitive of meteorites, have been believed to be derived from asteroids, but oxygen isotopic compositions of asteroids themselves have not been established. We measured, using secondary ion mass spectrometry, oxygen isotopic compositions of rock particles from asteroid 25143 Itokawa returned by the Hayabusa spacecraft. Compositions of the particles are depleted in (16)O relative to terrestrial materials and indicate that Itokawa, an S-type asteroid, is one of the sources of the LL or L group of equilibrated ordinary chondrites. This is a direct oxygen-isotope link between chondrites and their parent asteroid.     

Soy isoflavonoid aglycons genistein and daidzein Do not increase the cytochrome P-450 content of the liver microsomes of mice

Mice (4-week-old, male ddy) were fed four isonitrogenic diets for 21 days: purified diet (C diet); fermented soybean (400 mg of soy isoflavonoids/kg; FSB); fermented soybean extract (400 mg of soy isoflavonoid aglycones/kg; FSBE); C with indole-3 carbinol (I3C) (2500 mg of I3C/kg; I3C). The I3C and FSB diets significantly increased the cytochrome P-450 content of hepatic microsomes in comparison with the C diet, while the FSBE diet did not. Other mice were fed seven diets for 21 days: C; C with 100 mg or 200 mg of genistein, 100 mg or 200 mg of daidzein, or 100 mg of genistein + 100 mg of daidzein/kg; I3C diet. Genistein and daidzein did not change the liver cytochrome P-450 content. There was no synergistic effect of the combined feeding of genistein and daidzein. The increase in the cytochrome P-450 content with the FSB diet depends on chemicals other than genistein and daidzein. Genistein and daidzein do not induce cytochrome P-450.     

Paired box 7 inhibits differentiation in 3T3‐L1 preadipocytes

Myogenesis is precisely proceeded by myogenic regulatory factors. Myogenic stem cells are activated, proliferated and fused into a multinuclear myofiber. Pax7, paired box 7, one of the earliest markers during myogenesis. It has been reported that Pax7 regulates the muscle marker genes, Myf5 and MyoD toward differentiation. The possible roles of Pax7 in myogenic cells have been well researched. However, it has not yet been clarified if Pax7 itself is able to induce myogenic fate in nonmyogenic lineage cells. In this study, we performed experiments using stably expressed Pax7 in 3T3‐L1 preadipocytes to elucidate if Pax7 inhibits adipogenesis. We found that Pax7 represses adipogenic markers and prevents differentiation. These cells showed decreased expression of PDGFRα, PPARγ and Fabp4 and inhibited forming lipid droplets.     

The discovery of dinotefuran: a novel neonicotinoid

Dinotefuran (MTI-446: (RS)-1-methyl-2-nitro-3-(tetrahydro-3-furylmethyl)guanidine) is a new neonicotinoid commercialized by Mitsui Chemicals. Research led to this novel neonicotinoid by the removal of the chloropyridine or chlorothiazole ring that had been considered as indispensable for neonicotinoides. The research advanced as follows; (1) selection of acetylcholine for the lead compound, (2) recognition of the insecticidal advantages of 3-methoxypropyl compounds, (3) synthesis of (+/-)-tetrahydro-3-furylmethyl compounds by cyclization of the 3-methoxypropyl moiety. It resulted in dinotefuran which has a (+/-)-tetrahydro-3-furylmethyl moiety instead of a halogenated aromatic heterocyclic ring, and belongs to the third-generation neonicotinoids (sub-class: furanicotinyl compounds).     

Race distribution of Phytophthora sojae on soybean in Hyogo, Japan

Since 1987, Phytophthora root and stem rot of soybean [Glycine max (L.) Merr. cv. Tanbakuro], caused by Phytophthora sojae Kaufman and Gerdemann, has been increasing in the Sasayama, Nishiwaki, and Kasai regions in Hyogo, the most famous soybean (cv. Tanbakuro)-producing areas in Japan. In 2002 to 2004, 51 isolates (one from each field) of P. sojae were recovered from 51 fields in Hyogo. These isolates were tested for virulence on six Japanese differential soybean cultivars used for race determination in Japan, and three additional ones containing four Rps genes used in Indiana, USA. Race E was the most prevalent from 2002 to 2004, followed by races A, C, D, and four new races (proposed as races K, L, M, and N). Interestingly, none of the new races had high virulence on the Japanese differential cultivars, compared with other races in each area. One (race N) was avirulent on all six soybean differentials. There was a difference in race distribution on each of three individual areas; race E seemed to be a major component of the P. sojae population in Sasayama, whereas race A and the new race M were the most prevalent in Nishiwaki and Kasai, respectively. Rps6 (cv. Altona) and Rps1a + Rps7 (cv. Harosoy 63) were infected by 90.2% and 33.3% of all isolates, respectively. However, Rps1d (cv. PI103091) was not susceptible to any of the 51 isolates, nor was cv. Gedenshirazu-1. These two soybean cultivars were considered to be potential sources of resistance to breed new resistant cultivars with the desirable characteristics of cv. Tanbakuro for this region.     

Retrotransposon-like elements in the genome of Verticillium dahliae may be used as DNA markers for fungal species and pathotypes

Using differential hybridization, two DNA fragments, VDf35 and VDf90, specific to Verticillium dahliae, were isolated. These fragments contained truncated open reading frames (ORFs) homologous to the gypsy-type retrotransposon. The ORFs of VDf35 and VDf90 were pol and gag homologs, respectively. In addition, VDf90 had a pol homolog without an ORF sequence. The pol homologs in VDf35 and VDf90 were similar to each other, and these two DNA fragments had completely identical sequences. Genomic Southern analysis revealed that numerous copies of these homologs existed in V. dahliae, suggesting that V. dahliae carries a gypsy-like retroelement. Genomic Southern and polymerase chain reaction (PCR) analysis also indicated that a large number of these homologs exist in V. longisporum as well as in V. dahliae, but only a few were present in V. albo-atrum. No homolog was found in either V. nigrescens or V. tricorpus. The uneven distribution of these homologs of the retroposon-like elements among Verticillium species suggested a close genetic kinship between V. dahliae and V. longisporum. PCR primers designed from VDf35 showed species- or pathotype-specific amplification. Therefore, this sequence may be useful as a DNA marker to identify species and pathotypes of V. dahliae. This is the first report on a retrotransposon-like sequence in the genome of phytopathogenic Verticillium species.The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession numbers AB095264 (VDf90) and AB095265 (VDf35)