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The regioselective intramolecular 1,3-dipolar cycloaddition of the phenylsulfonylallene-nitrone derivatives has been developed. This reaction showed that the distal double bond of the allene exclusively reacted with the nitrone group to produce the bicyclic isoxazolidine derivatives regardless of the substitution pattern on the allenyl moiety.

To assess the effects of light from an integrated optical microscope and evaluate the safety of time-lapse observations using a built-in microscope incubator.We prospectively compared the fertilization rate and embryonic morphology after intracytoplasmic sperm injection between embryos cultured with time-lapse observations every 15 min in an incubator with an integrated optical microscope and embryos with intermittent observations (once a day) in conventional incubators.No significant differences were observed in the fertilization rate (57.5% vs. 57.5%) or the rate of excellent-good cleavage embryos (36.0% vs. 36.0%).These results suggest that time-lapse observations using an incubator with an integrated optical microscope may therefore be safely utilized in clinical practice.

Intramolecular cycloaddition of a variety of in situ generated phenylsulfonyl-substituted allene-nitrones proceeds exclusively at the distal double bond to afford fused isoxazoles, irrespective of the substitution pattern at the allene.

Two-stage two-stream continuous ethanol fermentation using flocculating yeast was studied to produce high ethanol concentration from blackstrap cane-molasses. Optimizing pH, RQ, cell concentration, and medium molasses concentration of the first stage to give a good cell yield without a significant decrease in ethanol yield, the final ethanol concentration of as high as 92.0–93.5 g/l at an overall dilution rate of 0.10 l/h was obtained. This process could work stably as long as 3 weeks without any decreases in the efficiency.

The effects of pCO2 were investigated by changing the aeration rate, the purging gas and the total pressure in a chemostat cultivatioa Under glucose supply limitation, an increase in pCO2 from 44 kPa to 195 kPa resulted in 25 % decrease in cell concentration, 8 % increase in ethanol concentration, and 50 % decrease in glycerol concentration. Under oxygen supply limitation, similar dependency of ethanol and glycerol on pCO2 was observed, however, no influence of pCO2 on the cell yield was observed. The change in ethanol yield by pCO2 appeared to be caused by the equilibrium shift of pyruvate dehydrogenase system.

Fluorine substitution on the methyl group of acetylferrocene and acetophenone strengthened anti-Prelog-type stereoselectivity in the microbial reduction with 6 strains of yeast ( e.g. , Rhodotorula rubra IFO 889) and one strain of bacterium. The cell-free extract of R. rubra was fractionated by polyacrylamide gel electrophoresis. Two fractions had prominent activity for NAD(P)H-dependent reduction of (trifluoroacetyl)ferrocene (1). One of the two fractions produced preferentially ( S )-2.2.2-trifluoro-1-hydroxyethylferrocene (2) as following Prelog's rule, while the other produced preferentially ( R )-2 with the anti-Prelog-type stereoselectivity.

We previously reported the isolation of the yeast suppressor gene for flocculation, SFL2 (TUP1). SFL2 gene disruption results in pleiotropic phenotypes; the sfl2 null mutation also causes a morphological change similar to shmoo in both the MAT alpha and MATa/alpha cells. The MAT alpha and MATa/alpha sfl2 null mutant cells incorporate chitin into the new growth zone in the same way as the alpha-factor-treated MATa cells. In order to clarify the molecular basis of this morphological change, we examined the effect of the sfl2 null mutation on the mRNA production of various genes involved in mating-type control. The transcripts of both the STE2 (an a-specific gene) and STE3 (an alpha specific gene) genes are detected in the MAT alpha and MATa/alpha cells carrying the sfl2 null mutation. In addition, mRNA of the GPA1 gene (haploid-cell-specific gene) is also detected in the MATa/alpha sfl2 cells. However, there is no significant difference in the levels of the MAT alpha 2 and MATa1 transcripts. These results suggest that the SFL2 gene product may be necessary for alpha 2 and a1-alpha 2 repression.

Asexual yeast flocculation was studied using strong flocculents of Saccharomyces cerevisiae. The inhibitory effect of cations on flocculation is considered to be caused by competition between those cations and Ca2+ at the binding site of the Ca2+-requiring protein that is involved in flocculation. Inhibition of flocculation by various cations occurred in the following order: La3+, Sr2+, Ba2+, Mn2+, Al3+, and Na+. Cations such as Mg2+, Co2+, and K+ promoted flocculation. This promoting effect may be based on the reduction of electrostatic repulsive force between cells caused by binding of these cations anionic groups present on the cell surface. In flocculation induced by these cations, trace amounts of Ca2+ excreted on the cell surface may activate the corresponding protein. The ratio of Sr2+/Ca2+ below which cells flocculated varied among strains: for strains having the FLO5 gene, it was 400 to 500; for strains having the FLO1 gene, about 150; and for two alcohol yeast strains, 40 to 50. This suggests that there are several different types of cell surface proteins involved in flocculation in different yeast strains. Key words: yeast, flocculation, protein, cation, calcium.

A simple and rapid screening method using bioassay for the simultaneous analysis of antibacterials (penicillins, cephalosporins, macrolides, tetracyclines, quinolones, etc.) in meat has been developed. A 5 g sample was homogenized with 5 mL of methanol, and the homogenate was centrifuged for 10 min with 3,000 rpm. The pulp disk method with Bacillus subtilis BGA (Antibiotic Medium 5 (pH 8) and 8 (pH 6)), Micrococcus luteus ATCC 9341 and Geobacillus stearothermophilus as test organisms was employed for the assay of the antibacterials. Typical antibacterials (penicillin G, ampicillin, cefapirin, cefalexin, erythromycin, spiramycin, oxytetracycline, chlortetracycline, streptomycin, dihydrostreptomycin, enrofloxacin and oxolinic acid) were detected at levels of ca. 0.005-2.5 microg/g in meat. Therefore, we recommend this proposed screening method for routine analysis of residual antibacterials in livestock products.

We have identified a yeast gene, SFL2 (suppressor gene for flocculation), which complemented a newly isolated sfl2 mutant. This mutation causes asexual cell aggregation. The strain bearing the SFL2 gene disruption exhibited pleiotropic phenotypes characteristic for tup1 mutants. Physical mapping and complementation analysis suggested that the cloned SFL2 gene is identical to the TUP1 gene. The SFL2 gene encodes a 669-amino acid protein which has domains rich in glutamine, as does the SSN6 protein.

We identified a yeast suppressor gene for flocculation ( SFL1 ), which complemented a newly isolated sfl1 mutant. This mutation causes asexual cell aggregation. SFL 1 encodes a 767-amino acid protein which has two domains significantly homologous to Myc oncoproteins and the yeast heat shock transcription factor (HSTF). The Myc homologous region in SFL 1 overlaps with the conserved region m a series of interesting proteins: MyoD1, Drosophila achaete-scute, twist, daughterless gene products and immunoglobulin enhancer-binding proteins. In addition, the N-terminal region of the SFL1 gene product shows extensive homology to the DNA-binding domain of HSTF. Mutational analysis of SFL1 demonstrates that it is required for normal cell-surface assembly in vegetative growth. We propose that the SFL 1 gene product may be a transcription factor which is involved in regulation of the gene(s) related to yeast flocculation.

Five hundred and forty-two abdominal computed tomography (CT) scans, including the kidneys, were reviewed to investigate the incidence of simple renal cysts. Increasing frequency with age was clearly demonstrated. The incidence in patients 50 years of age and over was at least 27%. Two thirds of simple renal cysts were 2 cm or less in diameter. Cysts were usually observed as exo-endoparenchymal or endoparenchymal lesions on CT.