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Received: 23 June 1993 / Accepted in revised form: 15 September 1994 相似文献
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K Motojima S Goto T Imanaka 《Biochemical and biophysical research communications》1992,188(2):799-806
The effect of clofibrate, a hypolipidemic drug and a potent peroxisome proliferator, on expression of a nonperoxisomal transthyretin (prealbumin) gene was studied using rats fed clofibrate for various periods. Upon feeding a diet containing clofibrate, the level of transthyretin mRNA was down-regulated, reaching 20% of the control level, in an almost reciprocal time course to that of increases in the levels of peroxisomal mRNAs. Studies on expression of other steroid hormone regulated genes suggest that clofibrate may down-regulate several but not all types of steroid hormone regulated mRNA expression. 相似文献
4.
Kazuhiro Haraguchi Shigeru Saito Hiromichi Tanaka Tadashi Miyasaka 《Nucleosides, nucleotides & nucleic acids》2013,32(2-4):483-493
Abstract Pummerer-type rearrangement of uracil nucleosides having a phenylseleno group in the 2′-, 3′-, and 5′-positions took place upon oxidation with MCPBA in CH2Cl2 followed by treatment with acid anhydrides to yield α-acyloxyselenides. 相似文献
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The subcellular distribution of hydrolases in germinating peacotyledons was investigated by differential and sucrose densitygradient centrifugations. Acid phosphatase was present in atleast two kinds of subcellular components. One was slightlyheavier than mitochondria, and the other was so light that itremained on the upper part of the gradient after sucrose densitygradient centrifugation. Protease was localized in the smooth-surfacedmicrosomal fraction which contained antimycin A-insensitiveNADH2-cytochrome c reductase and no RNA. Aryl esterase existedin a soluble form in the cytoplasm. (Received July 22, 1971; ) 相似文献
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The relationship between surface marker expression and encephalitogenicity of lymphocytes from various lymphoid organs of Lewis rats was studied. The encephalitogenicities after culture with BP were spleen cells greater than lymph node cells much greater than thymus cells, in this descending order. The cells from every lymphoid organ proliferated significantly in response to BP. In spleen and lymph node cells, the expression of W3/25 and OX-3 molecules on T cells increased markedly after culture with BP, but the expression of OX-19 or OX-8 molecules did not change significantly. The up-regulations of W3/25 and OX-3 molecules were more pronounced in spleen cells than in lymph node cells. Thymus cells also showed a significant increase in the W3/25 molecule after the culture with BP. Therefore, T cells from all the lymphoid organs showed a selective up-regulation of the W3/25 molecule after culture with BP, and the degree of the up-regulation seems to correspond to the encephalitogenic potency in vivo. Since the W3/25 molecule apparently plays a direct role in the effector phase of experimental allergic encephalomyelitis (EAE) by enhancing BP-reactive T cell/antigen-presenting cell interaction in the central nervous system, the up-regulation on BP-cultured T cells may strengthen interaction with the class II major histocompatibility complex molecule on antigen-presenting cells, and therefore, contribute to the efficient transfer of EAE. 相似文献
8.
H Furuya M J Saraiva M A Gawinowicz I L Alves P P Costa H Sasaki I Goto Y Sakaki 《Biochemistry》1991,30(9):2415-2421
Transthyretin (TTR) is a plasma protein interacting with thyroxine T4 and retinol binding protein (RBP). Several variants of TTR with single amino acid substitutions have been identified as the major components of the amyloid fibrils of familial amyloidotic polyneuropathy (FAP), a fetal, autosomal dominant genetic disease. The elucidation of the molecular nature of the variants distinct from that of the wild-type TTR is crucial for understanding the amyloidogenesis in FAP, but our understanding is very poor mainly because of the unavailability of pure variant TTRs. In the present study, we used an Escherichia coli OmpA secretion vector (Ghrayeb et al., 1984) and achieved an effective production of the variant TTRs related to FAP including Met-30, Ile-33, Ala-60, Tyr-77, Met-111, and Ile-122 types. The variant TTRs produced in this system were efficiently secreted to the culture media. The chemical analysis showed that the secreted TTR (Met-30 type) has the same N-terminus as the native one. IEF analyses also indicated that the secreted product is properly processed as assessed by its pI. Furthermore, the secreted TTR was shown to have biological activities, namely, the thyroxin binding activity and the ability to associate with retinol binding protein, indicating that the secreted TTR polypeptide is properly folded. The present work also demonstrated that the processing/secretion of the recombinant TTR molecules in E. coli was strongly affected by single amino acid substitutions. 相似文献
9.
Bacteriocin sensitivity typing according to the method of Traub (Appl. Microbiol. 1971. 21: 837-840) was carried out on 226 clinical isolates of Serratia marcescens obtained from inpatients at Nagasaki University Hospital during the period from January 1976 to December 1978. The isolates were divided into 16 different bacteriocin types, mainly 26, 4, and 9. The distribution of the types suggests that Serratia marcescens infections may be caused by cross infection. Reproducibility of bacteriocin typing and the relationship between serotypes (O-antigen) and bacteriocin types are discussed in regard to the application of this method to the study of nosocomial infections. 相似文献
10.
Synthesis of cytochrome c oxidase in the liver of Rana catesbeiana tadpole treated with griseofulvin
The effect of griseofulvin treatment on the synthesis of cytochrome c oxidase was studied with the liver of the tadpole, Rana catesbeiana. (1) In the liver of tadpole treated with griseofulvin, a ferrochelatase inhibitor, the synthesis of heme a, but not cytochrome c oxidase protein, is inhibited. (2) The apocytochrome c oxidase which is formed in the liver of tadpole treated with griseofulvin is converted to the active holoenzyme by exogenously added heme a. 相似文献