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Optically active trans-2-(arylthio or alkylthio)cyclohexanols are prepared by the asymmetric ring-opening of cyclohexene oxide with various arylthiols or alkylthiols in 52–85% ee by the use of zinc Lq-tartrate as a heterogeneous chiral Lewis acid catalyst.

Optically active bicyclic lactones are synthesized from ircides, derived from (R)-(−)-2-amino-2-phenylethanol and meso-cyclic-1,2-cis-dicarboxylic acids, by successive treatment with sodium bis(2-m...

In a recent publication, we reported that deoxycholic acid is 7 alpha-hydroxylated to yield glycocholate or taurocholate in vivo in the hamster (1987. Kuroki et al. Hepatology. 7: 229-234). In order to explore the possibility that amidation of free deoxycholic acid precedes the 7 alpha-hydroxylation, we assayed 7 alpha-hydroxylase activities of free and conjugated deoxycholates in vitro. 7 alpha-Hydroxylase activities of glycodeoxycholate and taurodeoxycholate were 720 +/- 132 and 640 +/- 160 pmol/mg.min-1, respectively. Activity of 7 alpha-hydroxylation of free deoxycholate was very low (60 +/- 20 pmol/mg.min-1). After treatment with phenobarbital in a dose of 100 mg/kg per day for 6 days, 7 alpha-hydroxylase activities of conjugated deoxycholates were decreased significantly (40%, P less than 0.01, n = 8), whereas that of free deoxycholate was not significantly changed. In the rat, 7 alpha-hydroxylase activities of conjugated deoxycholates were induced significantly (45% increase, P less than 0.05, n = 5) by phenobarbital treatment in sharp contrast to the hamster. There were significant correlations between the 7 alpha-hydroxylase activity of taurodeoxycholate and that of glycodeoxycholate both in the hamster and in the rat (hamsters: n = 16, r = 0.98, P less than 0.01; rats: n = 10, r = 0.82, P less than 0.01). These studies suggested that deoxycholic acid is 7 alpha-hydroxylated after amidation with glycine or taurine in vivo and that the same enzyme may well catalyze the 7 alpha-hydroxylation of glycodeoxycholate and taurodeoxycholate in the hamster.(ABSTRACT TRUNCATED AT 250 WORDS)

The asymmetric ring-opening of symmetrical oxiranes with aniline or trimethylsilyl azide is effectively catalyzed by zinc (2R,3R)-tartrate or cupric (2R,3R)-tartrate to give trans N-phenyl (β-amino alcohol or trans O-trimethylsilyl 2-azido alcohols in 17–52% ee. The latter azido products can be easily converted into optically active trans β-amino alcohols by two-step procedure.

A simplified and accurate assay of cholesterol 7α-hydroxylase activity using 5α-cholestane-3β,7β-diol as an internal standard is described. Endogenous microsomal cholesterol was used as the substrate. Following incubation and addition of the internal standard, lipids extracted from the incubation mixture were applied to Bond-Elut silica cartridge columns. 7α-Hydroxycholesterol, 7β-hydroxycholesterol, 7-ketocholesterol and the internal standard were quantitatively recovered by eluting the column with 6 ml of benzene—ethyl acetate (2:3, v/v) after removal of cholesterol with 6 ml of benzene—ethyl acetate (9:1, v/v). After trimethylsilylation, the mass of 7α-hydroxycholesterol was determined by capillary gas chromatography with selected-ion monitoring. The method permits a faster, easier and more sensitive determination of the activity of cholesterol 7α-hydroxylase in small samples.

(S)-(−)-Diisopropyl phenylthiosuccinate (81% optical purity) is prepared in 95% yield by the asymmetric Michael addition of thiophenol to diisopropyl maleate in the presence of a catalytic amount of cinchonine. The succinate thus prepared is transformed into (R)-(+)-3,4-epoxy-1-butanol without racemization.

The asymmetric ring opening of meso-2,3-disubstituted oxiranes with thiols, aniline, and trimethylsilyl azide was studied by the use of metal(II) d-tartrates as heterogeneous chiral Lewis acid catalysts. The enantioselectivity varied widely with the combination of oxirane, nucleophile, and metal(II) d-tartrate, and Zn(II) d-tartrate gave the best enantioselectivity in the respective reactions of 1,2-epoxycyclohexane with 1-butanethiol, aniline, and trimethylsilyl azide to afford the corresponding adducts in 85, 58, and 42% ee, respectively. Furthermore, the kinetic resolution of racemic oxiranes with thiols catalyzed by Zn(II) d-tartrate was studied.

The influence of heater material on free-convective heat transfer from wires to carbon dioxide in the supercritical region was investigated. Three types of flow configuration were observed for nichrome and alumel wires: (a) conventional laminar-flow free convection, (b) an oscillating flow in which (a) and a bubble-like flow alternated, (c) a bubble-like flow in which masses of fluid similar to bubbles appeared successively near the heating surface. Neither (b) nor (c) was observed with a platinum wire. The heat-transfer rate increased suddenly when the flow configuration changed from (a) to (b). The transition in flow structure occurred when the temperature difference between the heater and fluid exceeded about 200 deg C.

The so-called “Secondary Shirasu (lacustrine or marine sediments of pyroclastics)” is distributed in separate forms and in small scale, and occurs in association with the socalled “Shirasu or Primary Shirasu (pyroclastic flow deposits)” which is widely distributed over southern Kyushu. Mineral and chemical compositions, and optics of constitutent minerals of the Secondary Shirasu, which was derived from the Aira Shirasu, have been studied, and are compared with those of the Primary Shirasu, i. e. the Aira Shirasu which came from the Aira volcanic caldera. Mineral and chemical compositions show that the Secondary Shirasu is characterized by lower content of mafic minerals and by higher silica and lower ferrous iron oxide and magnesia contents than the Primary Shirasu. The differences in chemical composition are consistent with those in mineral composition between the Secondary and Primary Shirasu. The nature of the Secondary Shirasu is reffected in these differences.

A fibrous mordenite was found in cavities in a rhyolite. The mordenite was formed probably by a result of hydrothermal mineralization.

In this study we used volcanic glass from Kagoshima. In the system of glass+NaOH, initial crystallization of the sodium form of chabazite occurs, followed by a gradual conversion to zeolite X, and finally Na-P zeolite begins to crystallize. In the system of glass+KOH, the potassium form of chabazite was formed after boiling for 14 hours. High structure form of albite was formed from the _??_odium form of chabazite upon heating at 530°C and the potassium form of chabazite was borken upon heating at 1000°C. There is replacement of the type Ca_??_Na2_??_K2 in chabazitc.

Objective Wegener’s granulomatosis (WG) is a relatively rare disease characterized by granulomatous necrotizing vasculitis that primarily involves small- and medium-sized vessels. Systemic findings observed on 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) have not been well reported. The purpose of this study was to evaluate the FDG PET/CT imaging in the diagnosis and follow-up of patients with WG. Materials and methods Thirteen FDG PET/CT images obtained for 8 patients (2 men and 6 women) with WG were retrospectively analyzed. Of these, 6 were performed for diagnosis, 2 for restaging and follow-up, and 5 for assessment of treatment efficacy. Maximum standardized uptake values (max SUVs) and visual analyses were used to interpret the FDG PET/CT images. In addition, nonenhanced CT findings obtained during FDG PET/CT were described. Results WG lesions of the upper respiratory tract and lung were more clearly detected by FDG PET/CT fusion imaging than by nonenhanced CT alone, and all of the active lesions showed decreased FDG uptake after treatment. In addition, FDG PET/CT can provide complementary information to indicate biopsy site based on FDG uptakes. Conclusions FDG PET/CT is a feasible modality for evaluating lesion activities, therapeutic monitoring, and follow-up of WG. Furthermore, biopsy sites of WG lesions may be determined by FDG PET/CT.

Die Thiole (I) addieren sich selektiv an Cyclohexenoxid (II) unter Katalyse durch das Zn-Tartrat (III) in guten optischen Ausbeuten zu den ′ β-Hydroxycyclohexylsul?den (IV).

Optically active bicyclic lactones are synthesized from ircides, derived from (R)-(−)-2-amino-2-phenylethanol and meso-cyclic-1,2-cis-dicarboxylic acids, by successive treatment with sodium bis(2-m...

The asymmetric ring-opening of symmetrical oxiranes with aniline or trimethylsilyl azide is effectively catalyzed by zinc (2R,3R)-tartrate or cupric (2R,3R)-tartrate to give trans N-phenyl (β-amino alcohol or trans O-trimethylsilyl 2-azido alcohols in 17–52% ee. The latter azido products can be easily converted into optically active trans β-amino alcohols by two-step procedure.

(S)-(−)-Diisopropyl phenylthiosuccinate (81% optical purity) is prepared in 95% yield by the asymmetric Michael addition of thiophenol to diisopropyl maleate in the presence of a catalytic amount of cinchonine. The succinate thus prepared is transformed into (R)-(+)-3,4-epoxy-1-butanol without racemization.

Advanced imaging techniques may enable early diagnosis and monitoring of therapy in various rheumatic diseases. To prevent irreversible tissue damage, inflammatory rheumatic disease must be diagnosed and treated in pre-clinical stages, requiring highly sensitive detection techniques. Positron emission tomography (PET) provides highly sensitive, quantitative imaging at a molecular level, revealing the important pathophysiological processes underlying inflammation. This review provides an overview of the current utility of 18 F-fluorodeoxyglucose (FDG)-PET/computed tomography (CT) in patients with active rheumatic diseases such as rheumatoid arthritis, spondyloarthritis, polymyalgia rheumatica, adult-onset Still's disease, relapsing polychondritis, immunoglobulin G4-related disease, large-vessel vasculitis, Wegener's granulomatosis, polymyositis, and dermatomyositis. We also discuss the role of FDG-PET/CT in the diagnosis and monitoring of these diseases.

GLUTAMIC acid strongly excites almost all central neurones examined, and it has been considered to be a main excitatory transmitter in the mammalian brain1,2. Although some neurones in the olfactory bulb have been inhibited by glutamic acid3, this has been explained by the assumption that glutamate primarily activated γ-aminobutyrate (GABA)-releasing inhibitory interneurones, which in turn inhibited the neurones in question1. In the experiments reported here, glutamate inhibited neurones in the granular layer of the cerebellum: this action does not seem to be mediated by inhibitory interneurones.

Rheumatoid arthritis (RA) is a systemic autoimmune inflammatory disorder that primarily affects the synovial joints. Rheumatoid vasculitis (RV) is an extra-articular manifestation of RA, and its association with aortitis is rare and not widely recognised. Here, we report the case of a 69-year-old woman with RA-associated aortitis and review the literature on rheumatoid aortitis. The mean oral steroid dose administered to RA-associated aortitis patients was 46.3 mg/day prednisolone (PSL). In our patient, the aortitis was also thought to be due to RV because she had findings of RV, such as cutaneous ulceration and a high rheumatoid factor titre, and because a moderate PSL dose dramatically improved the clinical findings. RA-associated aortitis, if left untreated, can be fatal; therefore, early detection and treatment initiation is very important.