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A virus (designated the Shintoku strain) which was morphologically indistinguishable from group A rotaviruses was detected in the feces of adult cows with diarrhea in Japan. The virus contained 11 segments of double-stranded RNA and had an electrophoretic migration pattern in polyacrylamide gels similar to that of other group C rotaviruses (4-3-2-2). Feces containing the bovine virus reacted with antiserum to porcine group C rotavirus (Cowden strain) but not group A or B rotaviruses in immunoelectron microscopy. The virus was adapted to serial propagation in roller tube cultures of a rhesus monkey kidney cell line (MA104) by using high concentrations of trypsin. Evidence for viral replication in MA104 cell cultures was demonstrated by immunoelectron microscopy and indirect immunofluorescence by using antiserum to porcine group C rotavirus and by electrophoretic analysis of extracted viral double-stranded RNA. A significant antibody response against the isolate was detected in convalescent-phase sera of cows which excreted the virus: no increased antibody response to bovine group A rotavirus was observed. To our knowledge, this is the first isolation of a group C rotavirus from cattle.

Dried apple peels were extracted with n-hexane, chloroform, and methanol successively. The portion of the chloroform extract that showed the strongest cytotoxic activity was purified by silica gel chromatography to isolate ursolic acid (UA). The amount of the isolated UA was 0.71% of the dried peels. Normal mouse embryo cells [serum-free mouse embryo (SFME) cells] and tumorigenic human c-Haras-and mouse c-myc-transformed SFME cells [r/m highly metastatic (HM)-SFME-1 cells] were treated with various concentrations of UA (2.5-20 µM) to investigate its effects on cell growth. UA at 10 µM appeared very effective at suppressing the tumor cell growth, affecting more than 82% of r/m HM-SFME-1 cells, while it inhibited cell growth in only about 7% of SFME cells. Tumorigenic r/m HM-SFME-1 cells were also treated with various concentrations (2.5-10 µM) of epidermal growth factor (EGF) or aminoguanidine (AG) in the presence of UA (2.5-10 µM). Neither EGF nor AG seemed to have any effect on UA-inhibited cell growth. In the present study, it is revealed that UA could be a very effective and promising agent for antitumor treatments, * To whom correspondence should be addressed: Department of Pharmacy, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tenpaku, Nagoya 468-8503, Japan. Tel.: +81-52-839-2721; Fax: +81-52-834-8090; E-mail: hyamagu@ccmfs. meijo-u.ac.jp as it specifically affects tumorigenic cells yet appears to cause very little harm to normal cells.

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Impaired 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2)-dependent cortisol inactivation can lead to electrolyte dysbalance, hypertension and cardiometabolic disease. Furthermore, placental 11β-HSD2 essentially protects the fetus from high maternal glucocorticoid levels, and its impaired function has been associated with altered fetal growth and a higher risk for cardio-metabolic diseases in later life. Despite its important role, 11β-HSD2 is not included in current off-target screening approaches. To identify potential 11β-HSD inhibitors among approved drugs, a pharmacophore model was used for virtual screening, followed by biological assessment of selected hits. This led to the identification of several azole fungicides as 11β-HSD inhibitors, showing a significant structure-activity relationship between azole scaffold size, 11β-HSD enzyme selectivity and inhibitory potency. A hydrophobic linker connecting the azole ring to the other, more polar end of the molecule was observed to be favorable for 11β-HSD2 inhibition and selectivity over 11β-HSD1. The most potent 11β-HSD2 inhibition, using cell lysates expressing recombinant human 11β-HSD2, was obtained for itraconazole (IC 139±14nM), its active metabolite hydroxyitraconazole (IC 223±31nM) and posaconazole (IC 460±98nM). Interestingly, experiments with mouse and rat kidney homogenates showed considerably lower inhibitory activity of these compounds towards 11β-HSD2, indicating important species-specific differences. Thus, 11β-HSD2 inhibition by these compounds is likely to be overlooked in preclinical rodent studies. Inhibition of placental 11β-HSD2 by these compounds, in addition to the known inhibition of cytochrome P450 enzymes and P-glycoprotein efflux transport, might contribute to elevated local cortisol levels, thereby affecting fetal programming.

Finally, using an inducible ROR reporter system, we showed that 11-HSD1 and 11-HSD2 controlled ROR activity. These findings revealed a novel glucocorticoidindependent prereceptor regulation mechanism by 11-HSDs that warrants further investigation.

Seasonal changes in the amounts of the NAD-dependent sorbitol dehydrogenase (NAD-SDH) (enzyme code, 1.1.1.14) protein in developing apple (Malus pumila Mill var. domestica Schneid) fruit were determined by immunoblotting analysis. The amounts of the enzyme protein were very low in young fruit and rose as fruit matured. The weak correlation between enzyme protein and NAD-SDH activity and also the changes in NAD-SDH specific activity suggested that there could be posttranslational modification to the pre-existing enzyme or isoenzyme(s) of NAD-SDH. The changes in the amounts of NAD-SDH protein did not show the same pattern as those in relative growth rate, which is used to express sink activity, especially in young fruit. The role of NAD-SDH on sink activity in apple fruit, therefore, could not be explained simply by the amount and activity of the enzyme. In young fruit, it seems that enzymes other than NAD-SDH would be more directly related with fruit growth.

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