Molecular Design, Characterization, and Application of Multiinformation Dyes (MIDs) for Optical Chemical Sensings. 3. Application of MIDs for λ(max)-Tunable Ion-Selective Optodes

By utilizing "multiinformation dyes (MIDs)", which have plural spectral change characteristics such as an absorption maximum wavelength (λ(max)) shift based on a polarity change and an absorbance change due to protonation, novel λ(max)-tunable ion-selective optodes were proposed and prepared by employing MIDs with membrane solvents having different polarities. For controlling the detecting λ(max) of the optode, the novel polar membrane solvent [2-[[6-(2-nitrophenoxy)hexyl]oxy]methyl]isobutane-1,3-diol was designed and synthesized, which was used together with a typical membrane solvent nitrophenyl octyl ether. By mixing these two membrane solvents, the λ(max) position of the optode detection wavelength can be shifted and controlled and was successfully applied to a λ(max)-tunable Li(+)-selective optode based on a highly Li(+)-selective ionophore TTD14C4. The λ(max) tuning technique is useful for preparing an optode system using a low-cost light source such as a light-emitting diode or a popular laser.     

17O Knight shift study in the superconducting state of Sr2RuO4

¹⁷O Knight shift measurements in Sr₂RuO₄ were performed over the wide range of magnetic field 3.2-11.4kOe parallel to the basal RuO₂ planes. The spin susceptibility is totally unchanged through its T_c, evidencing that the spin-triplet superconducting state is realized in Sr₂RuO₄. The result indicates that the Cooper pairs consist of the parallel spin pairs | > and | > with their quantization axis perpendicular to the c-axis direction. The in-plane 2D nearly ferromagnetic spin fluctuations may play a role for the stabilization of this state among various representations of spin-triplet order parameter.     

Supplementation with isoflavonoid phytoestrogens does not alter serum lipid concentrations: a randomized controlled trial in humans

Isoflavonoids are a class of flavonoids that are derived in the human diet mainly from soybean-based foods. The major dietary isoflavonoids, genistein and daidzein, have estrogen-like activity and are classed as phytoestrogens. Because estrogens can lower serum LDL cholesterol and raise HDL cholesterol, the objective of this study was to determine if isoflavonoids could improve serum lipids in healthy subjects. Forty-six men and 13 postmenopausal women not receiving hormone replacement therapy completed a randomized, double-blind, placebo-controlled trial of two-way parallel design and 8 wk duration. One tablet containing 55 mg of isoflavonoids (predominantly in the form of genistein) or one placebo tablet was taken daily with the evening meal. Subjects maintained their usual diet and physical activity, which were unchanged throughout the intervention. Measurement of isoflavonoids and their metabolites in 24-h urine samples provided an assessment of compliance and of isoflavonoid metabolism. Serum total, LDL, HDL and HDL subclass cholesterol, triglycerides and lipoprotein (a) were assessed at baseline and during the last week of intervention. After adjustment for baseline values, no significant differences in postintervention serum lipid and lipoprotein (a) concentrations between groups were identified. Further adjustment for age, gender and weight change did not alter the results. In addition, changes in urinary isoflavonoids were not significantly correlated with changes in serum lipids and lipoprotein (a). Therefore, this study does not support the hypothesis that isoflavonoid phytoestrogens can improve the serum lipids, at least in subjects with average serum cholesterol concentrations.     

Implications of gastric topical bioactive peptides in ammonia-induced acute gastric mucosal lesions in rats

BACKGROUND: Ammonia, one of the pathogenic factors in Helicobacter pylori-induced mucosal injury, induces acute mucosal lesions in the rat glandular stomach. METHODS: The effect of ammonia administered intragastrically on gastric peptides was investigated in urethane-anesthetized rats. RESULTS: Gastric mucosal lesions were observed 5 min after 0.3% ammonia (4 ml/kg, intragastrically). Immunoreactive endothelin-1 (ET-1) and immunoreactive thyrotropin-releasing hormone (TRH) concentrations in the gastric wall decreased significantly 2 min and 5 min after ammonia, respectively. A significant increase in gastric juice immunoreactive ET-1 and TRH levels was reciprocally observed. The severity of gastric mucosal injury and changes in gastric immunoreactive ET-1 and TRH concentrations were shown to be concentration-dependent 30 min after ammonia. Atropine (5 mg/kg, intraperitoneally, -20 min) prevented ammonia-induced injury accompanied by a block of changes in gastric immunoreactive ET-1 and TRH concentrations. BQ-485 (ET(A) receptor antagonist; 2 mg/kg, subcutaneously) also abolished ammonia-induced lesions and gastric immunoreactive TRH changes. CONCLUSIONS: These findings suggested that gastric ET-1 and TRH play a role in ammonia-induced gastric mucosal injury mediated via a muscarine and an ET(A) receptor.     

Calmodulin antagonists increase the expression of membrane-type-1 matrix metalloproteinase in human uterine cervical fibroblasts

The treatment of human uterine cervical fibroblasts with concanavalin A (ConA), or a specific calmodulin antagonist, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) or trifluoperazine resulted in accumulation of an active form of matrix metalloproteinase 2 (MMP-2, gelatinase A). In contrast, N-(6-aminohexyl)-1-naphthalenesulfonamide (W-5), a weaker antagonist of calmodulin, did not modulate the activation of proMMP-2. The activation of proMMP-2 was confirmed by the enhanced activity on gelatin and the conversion of proMMP-2 to a 62-kDa form by zymography and western blotting. The plasma membrane, but not the conditioned medium, of the W-7- or trifluoperazine-treated cells activated proMMP-2; this activation was blocked by membrane-type-1 MMP (MT1-MMP) antibody and EDTA. The plasma membrane from trifluoperazine- or ConA-treated cells contained MT1-MMP and tissue inhibitor of metalloproteinases 2. Both trifluoperazine treatment and ConA treatment increased the steady-state levels of MT1-MMP mRNA and proMMP-2 mRNA. These results, together with our previous observations on the production of proMMP-1 (interstitial procollagenase) and proMMP-3 (prostromelysin 1) [Ito, A., Sato, T., Ojima, Y., Chen, L.-C., Nagase, H. & Mori, Y. (1991) J. Biol. Chem. 266, 13598-13601], suggest that calmodulin negatively regulates the matrix turnover by suppressing the production of a number of proMMPs including proMMP-1, proMMP-3 and MT1-MMP, and the activation of proMMP-2 in human uterine cervical fibroblasts.     

Heterogeneous pattern of gene expression in cloned cell lines established from a rat transplantable osteosarcoma lung metastatic nodule

We have established three cloned cell lines (COS1NR, COS2NR and COS4NR) from the lung metastatic nodule of a highly metastatic variant of rat transplantable osteosarcoma, C-SLM. All three clones shared the same morphological characteristics and tumorigenicity, but their growth rates in vitro and metastatic ability in vivo differed from each other. Single-strand conformation polymorphism (SSCP) analysis revealed all three clones to have the same p53 gene mutation and parent C-SLM tumor. On the other hand, Northern blot analysis showed a different pattern of expression for the genes, c-fos, c-jun, c-Ha-ras, transin (rat stromelysin), bone Gla protein (osteocalsin) and nm23/NDP kinase. These results indicate the presence of a heterogeneous cell population in terms of the different pattern of gene expression in a lung metastatic nodule of rat osteosarcoma and the present newly established cell lines will be useful for further investigation of the biological behavior of osteosarcomas.     

Chondroitin sulfate proteoglycans protect cultured rat's cortical and hippocampal neurons from delayed cell death induced by excitatory amino acids

Protective effects of chondroitin sulfate proteoglycans (CSPGs) from rat's brain against delayed cell death induced by excitatory amino acids were examined in cultured neurons of the rat. CSPGs reduced delayed neuronal death induced by 10 min exposure to glutamate at a concentration between 100 microM and 1 mM when lactate dehydrogenase activity of culture medium was assayed 24 h after the exposure. CSPGs also protected neuronal death induced by 200 microM N-methyl-D-aspartate (NMDA), kainate or 100 microM alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA). CSPGs reduced death of cortical and hippocampal neurons even when they were administered at 2 h, but not 6 and 12 h, after the exposure to glutamate. These results indicate that CSPGs may have a neuroprotective action against acute noxious conditions in the brain.     

Preovulatory changes of steroidogenesis in isolated rabbit follicles (author's transl)

In an attempt to investigate the effect of ovulating hormone on the steroidogenesis of mature follicles in the course of ovulation, transitory changes of steroidogenesis in isolated rabbit follicles have been studied at several intervals after injection of an ovulatory dose of human chorionic gonadotropin (hCG). Five to ten follicles of approximately 1-2 mm in diameter were isolated from ovaries of a mature rabbit (2.5-3.0 kg) under streomicroscope, before and at the 3rd, 6th, 9th and 12th hours after intravenous injection of of 100 IU/kg of hCG. Follicles were incubated with 100 muCi of acetate-1-14C in 2 ml of Krebs-Ringer bicarbonate buffer (pH 7.4) at 37 degrees C for 3 hours under 95% oxygen plus 5% carbon dioxide. Each incubation was terminated by quick freezing and stored forzen at -20 degrees C until eighty follicles had been collected for each time period before commencement of analysis. Incorporation of radioactive acetate into pregnenolone, 17-hydroxypregnenolone, progesterone, 17-hydroxyprogesterone., 20 alpha-dihydroxyprogesterone, dehydroepiandrosterone, androstenedione, testosterone, estrone and estradiol-17beta were analysed by the reverse dilution technique and identified in radiochemically pure form by recrystallization to constant specific activities. The steroidogenic activity of the follicles was evaluated by overall as well as fractionated incorporations. A peak in the overall incorporation of 14C- acetate into the ten steroids at the 3rd hour after hCG injection, followed by gradual decrease up to the 9th hour was observed. The incorporation decreased markedly to a minimum level at the 12th hour after hCG injection, which was below the level of preinjection control. Comparable quantitative fluctuations were found with the fractionated incorporation of 14C-acetate into the C21 and C18 steroids in the time sequence following hCG injection. However, the fractionated incorporation into C19 steroids reached to a maximum at the 6th hour after hCG injection. 5istribution patterns of incorporation among the individual steroids were varied at each interval of time. In the non-injected control, mature follicles synthesized predominantly estradiol-17beta, testosterone and androstenedione. Divergent steroids were formed from radioactive acetate at the 3rd hour after hCG injection. These included porgestogen, androgen and estrogen, but pregnenolone and 17hydroxyprogesterone were the two principal steroids produced. There was no essential difference in the steroidogenic patterns between the 6th and 9th hour, the major products being C21 and C19 steroids such as pregnenolone, 17hydroxyprogesterone, dehydroipiandrosterone and testosterone. The three androgens were the major steroids formed at the 12th hour after hCG injection. Thus the chages in the steroidogenic profile of the follicle was obvious in the course of ovulation. The basis of qualitative changes in follicular steroidogenesis during the process of ovulation have been discussed in connection with an accompanying effect of an ovulatory dose of hCG.