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Volume 115, Issue 5
Displaying 1-5 of 5 articles from this issue
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Shinichiro SAKAI1995 Volume 115 Issue 5 Pages 351-369
Published: May 25, 1995
Released on J-STAGE: May 30, 2008
JOURNAL FREE ACCESSUp to now, more than two thousands indole alkaloids having structural variety have been found from the three families of Gentianales : Loganiaceae, Apocynaceae, and Rubiaceae plants. These compounds generally possess characteristic biological activities and many of them are utilized for the medicinal purpose and for the lead-compounds to develop new synthetic drugs. The author of this review has been investigated the alkaloidal constituents of the above mentioned plants native to Japan and overseas countries. Especially, a cooperative work with Thai researchers concerning the plants in Thailand was developed. On the basis of biogenetic consideration of the structures of monoterpenoid indole alkaloids, chemical bond cleavage between the C3-N4 linkage in the C/D ring of indole alkaloids was discovered. It was speculated that, either in biogenesis, the flexibility of the ring-opening compounds having ten membered ring enabled the construction of indole alkaloids having highly strained polycyclic structures. Along with this conception, the syntheses of structurally complex indole alkaloids utilizing a biomimetic procedure have been investigated. In this review, recent results on the chemical synthesis of many skeletally varied Gelsemium alkaloids (Loganiaceae plant) are mainly described.View full abstractDownload PDF (1232K) -
Tetsuya KAMATAKI1995 Volume 115 Issue 5 Pages 370-377
Published: May 25, 1995
Released on J-STAGE: May 30, 2008
JOURNAL FREE ACCESSIt is theoretically impossible to extraporate the toxicity of drugs in humans from data obtained with experimental animals. In fact, accumulated data on species differences in the drug metabolism can provide only a little information for the estimation of the metabolism and the related toxicity of drugs under development in humans. The recent development in the molecular biology has realized the quantitative estimation of genetic distance between humans and experimental animals. Thus, this study was undertaken to estimate the distance between humans and experimental animals to propose the use of monkeys in an initial phase of the development of a new drug. Cell lines carrying human drug metabolizing enzymes are also expected to be a good tool for the estimation of the drug metabolism and the toxicity of drugs in humans. To show an example of the usefullness of such cell lines, we established new cell lines expressing CYP3A7, a form of cytochrome P450 specifically present in human fetal livers.View full abstractDownload PDF (743K) -
Tamotsu YASHIRO1995 Volume 115 Issue 5 Pages 378-389
Published: May 25, 1995
Released on J-STAGE: May 30, 2008
JOURNAL FREE ACCESSIn clinical practice, the importance of analyses for biological materials has increased remarkably. The circumstances of the determination methods, i. e. using oxidative or reductative reactions as their bases, are reviewed. Then, I present the methods we developed. The objective substances include metal containing proteins, such as ceruloplasmin, diamine oxidase, and hemoglobin, and organic carbonic acids, such as xanthurenic acid, uric acid, and lactic acid. Since these substances are hardly related to some conditions of diseases, they are usually measured on routine clinical analysis either oxidatively or reductatively, and are afford interest in the reactivity, reacting processes, etc., emphatically.View full abstractDownload PDF (1051K) -
Kenji SUGIYAMA, Tilman VOSS, Horst AHORN, Ingrid MAURER FOGY, Edward L ...1995 Volume 115 Issue 5 Pages 390-393
Published: May 25, 1995
Released on J-STAGE: May 30, 2008
JOURNAL FREE ACCESSThe interferons (IFN) were discovered in 1957 as biological agents interfering with viral replication. IFNs were initially classified according to their sources as leukocyte, fibroblast and immune IFNs. Both leukocyte and fibroblast IFNs are designated as Type I IFNs and immune IFN as a Type II IFN. There are almost twenty related IFNs which belong to the group of Type I IFN. IFN-α2 and IFN-ω1 are described as members of the large group of Type I IFN. Both natural IFN-α2 and IFN-ω1 are isolated from human leukocytes. IFN-α2 carries an O-linked carbohydrate moiety, whereas IFN-ω1 has an N-linked complex oligosaccharide. Recombinant IFN-α2 expressed in E coli. and Sf-9 cells have been characterized. Moreover, recombinant IFN-ω1 expressed in CHO cells and Sf-9 cells have also been characterized. In the present study, the recombinant human IFN-α2 and IFN-ω1 were analyzed for their anti-viral activity compared with native products.View full abstractDownload PDF (485K) -
Masako ODA, Masafumi SASAYA, Takeshi HIRANO, Yuko NAKAJIMA, Katsuki IW ...1995 Volume 115 Issue 5 Pages 394-399
Published: May 25, 1995
Released on J-STAGE: May 30, 2008
JOURNAL FREE ACCESSThe mechanisms involved in the renal excretion of quinolone and new quinolone antibacterial drugs are still incompletely understood. The purpose of this study was to examine the renal handling of nalidixic acid (NA) and enoxacin (ENX), using the renal cortical slices uptake techniques in rats. It was demonstrated that both NA and ENX were taken against a concentration gradient by a saturable processes resulting from the ratio of slice to medium (ratio of S/M) being dependent on the time and the concentration. It was indicated that the inhibition of uptake by 2, 4-dinitrophenol, ouabain and sodium cyanate was shown to be an energy dependence. Probenecid and cimetidine exhibited that they might inhibit NA uptake slightly. ENX uptake was inhibited by probenecid, cimetidine, guanidine and disopyramide, suggesting that ENX might possess an affinity for both anionic and cationic transport mechanisms.View full abstractDownload PDF (555K)
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