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21.
Constitutive and interleukin-1 (IL-1)-inducible factors interact with the IL-1-responsive element in the IL-6 gene. 总被引:28,自引:14,他引:14 下载免费PDF全文
H Isshiki S Akira O Tanabe T Nakajima T Shimamoto T Hirano T Kishimoto 《Molecular and cellular biology》1990,10(6):2757-2764
The interleukin-6 (IL-6) promoter is rapidly and transiently activated with other cytokines, including IL-1, tumor necrosis factor, and platelet-derived growth factor, as well as phorbol esters and agents that increase intracellular cyclic AMP. In this study, we have investigated cis-acting regulatory elements and trans-acting factors responsible for IL-1-induced IL-6 gene expression. Studies on the 5' deletion mutants of the human IL-6 gene suggested that the IL-1-responsive element was mapped within the IL-6 promoter region (-180 to -123) which was homologous to the c-fos serum-responsive enhancer element. Gel retardation assay identified two types of nuclear factors that bound to this region, one constitutive and the other inducible. These two factors recognized a 14-base-pair (bp) palindromic sequence, ACATTGCACAATCT. Furthermore, three copies of this 14-bp palindrome conferred IL-1 responsiveness to the basal enhancerless IL-6 promoter, indicating that a 14-bp-dyad symmetry sequence was an IL-1-responsive element in the IL-6 gene. 相似文献
22.
Akira Goto 《Environmental Biology of Fishes》1990,28(1-4):101-112
Synopsis Japanese freshwater sculpins consist of 6Cottus and 1Trachidermus species, with various types of life-cycles, namely, catadromous, amphidromous, lacustrine land-locked and fluvial land-locked. Among them,C. amblystomopsis andC. nozawae have been regarded as sibling species. Because of very similar morphological and ecological adult characteristics they were formerly classified as a single species.C. amblystomopsis mainly inhabits the lower courses of rivers and produces many small eggs from which pelagic larvae are formed. In contrast,C. nozawae lives in the middle or upper courses of rivers and deposits few, large eggs, from which well-developed benthic young emerge, well on the way to the definitive phenotype as fully formed juveniles. These two species have distinctly different life-cycles: amphidromous forC. amblystomopsis and fluvial forC. nozawae. A comparison of the early ontogeny shows that, amongCottus species, the small-egg, amphidromousC. amblystomopsis is altricial, while the large-egg, fluvialC. nozawae is precocial. Assuming thatC. nozawae has been derived phylogenetically fromC. amblystomopsis or its ancestral relatives, it is reasonable to consider that the fluvial land-locked life-history style ofC. nozawae has evolved from the ancestral arnphidromous one through adapting to the upstream habitat by an increase in egg size and consequent truncation of the larval period. 相似文献
23.
The vascular anatomy ofHelminthostachys zeylanica was examined with special reference to anomalous secondary tissue. Primary xylem development gradually takes place centrifugally. In branched rhizomes with destroyed apices, the vascular cylinder apical to the insertion of branch traces is generally composed of primary xylem, accessory xylem, inner parenchyma of radially arranged cells, outer parenchyma of irregularly arranged cells, and partly crushed phloem, listed in order going outwards. The accessory xylem as well as the inner parenchyma ofHelminthostachys zeylanica is probably secondarily produced, partly to contribute to the branch traces, in a position corresponding to that of secondary vascular tissue developed from a normal cambium inBotrychium sensu lato. It is suggested that although a cambium is lacking inHelminthostachys zeylanica, the secondary vascular tissues are comparable between the genera. The phylogenetic implication of this tissue is discussed. 相似文献
24.
Hiroshi Yonemitsu Koichiro Shimomura Motoyoshi Satake Shunji Mochida Masahiko Tanaka Thoru Endo Akira Kaji 《Plant cell reports》1990,9(6):307-310
Hairy roots were obtained following inoculation of the stems of Lobelia inflata L. with Agrobacterium rhizogenes strain ATCC 15834. These hairy roots contained agropine and mannopine. In addition, lobeline was detected by HPLC and confirmed by mass spectrometry. Various media were tested for the growth of hairy roots as well as for the content of lobeline in hairy roots. The growth rate of hairy roots cultured in Nitsch and Nitsch's medium was approximately one third of those cultured in other media. The lobeline content of hairy roots (18–54 g/g dry weight) cultured in these media was the same order of magnitude compared with that of roots of L. inflata (24 g/g dry weight) cultivated in pots. The hairy roots cultured in Nitsch and Nitsch's medium were morphologically different from those cultured in other media.Abbreviations MS medium
Murashige and Skoog's medium
- 1/2 MS medium
one-half strength of the standard Murashige and Skoog's medium
- B5 medium
Gamborg's B5 medium
- NN medium
Nitsch and Nitsch's medium
- FW
fresh weight
- DW
dry weight 相似文献
25.
Alterations of human erythrocyte membrane fluidity by oxygen-derived free radicals and calcium 总被引:9,自引:0,他引:9
Hiroshi Watanabe Akira Kobayashi Takahashi Yamamoto Shingo Suzuki Hideharu Hayashi Noboru Yamazaki 《Free radical biology & medicine》1990,8(6):507-514
Two possible reasons for the structural alterations of cell membranes caused by free radicals are lipid peroxidation and an increase in the intracellular calcium ion concentration. To characterize the alterations in membrane molecular dynamics caused by oxygen-derived free radicals and calcium, human erythrocytes were spin-labeled with 5-doxyl stearic acid, and alterations in membrane fluidity were quantified by electron spin resonance oxidase (0.07 U/mL) decreased membrane fluidity, and the addition of superoxide dismutase and catalase inhibited the effect on membrane fluidity of the hypoxanthine-xanthine oxidase system. Hydrogen peroxide (0.1 and 1 nM) also decreased membrane fluidity and caused alterations to erythrocyte morphology. In addition, a decrease in membrane fluidity was observed in erythrocytes incubated with 2.8 mM CaCl2. On the other hand, incubation of erythrocytes with calcium-free solution decreased the changes in membrane fluidity caused by hydrogen peroxide.
These results suggest that changes in membrane fluidity are directly due to lipid peroxidation and are indirectly the result of increased intracellular calcium concentration. We support the hypothesis that alterations of the biophysical properties of membranes caused by free radicals play an important role in cell injury, and that the accumulation of calcium amplifies the damge to membranes weakened by free radicals. 相似文献
26.
Nobutaka Fujii Akira Otaka Susumu Funakoshi Toshihiro Watanabe Hiromitsu Arai Kiyoshi Bessho Haruaki Yajima 《Journal of Protein Chemistry》1988,7(2):151-156
Treatment of a mixture of Cys(R)(O) and Cys(R) with an acid was found to generate cystine in fairly good yields, when suitable R, R, and an acid were selected. An unsymmetrical cystine peptide was prepared by treatment of a mixture of Z(OMe)-Cys(R) (0)-Ala-NH2 (R=Acm or MBzl) and Z(OMe)-Cys(MBzl)-Gly-OBzl with TFA or 1 M TFMSA/TFA.3 Oxytocin was obtained in an excellent yield by TFA treatment of the protected peptide containing Cys(Acm)(0) and Cys(MBzl). Thus, formation of the disulfide bond was found feasible at the position of Cys(R) (0).The following abbreviations are used Boc
t-butyloxycarbonyl
- Z(OMe)
p-methoxybenzyloxycarbonyl
- MBzl
p-methoxybenzyl
- Acm
acetamidomethyl
- Bzl
benzyl
- Ad
l-adamantyl
- tBu
t-butyl
- TFA
trifluoroacetic acid
- TFMSA
trifluoromethanesulfonic acid
- TMSOTf
trimethylsilyl trifluoromethane sulfonate 相似文献
27.
Hiroshi Suzuki Hideaki Taguchi Kazuko Nishimura Makoto Miyaji Akira Nakamura Hironori Nakajima 《Mycopathologia》1988,104(1):7-17
Summary The authors succeeded in establishing a murine model of systemic candidiasis being disseminated from the primary gastrointestinal lesions caused by oral inoculation of Candida albicans. Using this model, an attempt was made for detecting the Candida antigen by enzyme-linked immunosorbent assay using avidin-biotin (AB-ELISA) from the serum of infected mice.Gastrointestinal candidiasis was formed in all of the 20 mice treated with the drugs (antibiotics, antineoplastic agents, hydrocortisone, etc.) and inoculated orally with C. albicans. Fourteen of these mice suffered from submucosal candidiasis, and C. albicans was cultured from the visceral organs in 12 of them. The assay by AB-ELISA was able to detect 1.0 ng/ml Candida mannan in the mouse serum. The Candida antigen was detected in the sera of 11 of the 14 mice with submucosal candidiasis. However, the antigen could not be detected in the sera of the 6 mice with intramucosal candidiasis.The assay by AB-ELISA is more sensitive and specific for the diagnosis of systemic candidiasis than other serological assays. 相似文献
28.
Akira Hiraishi 《Archives of microbiology》1988,150(1):56-60
Nineteen established and one undesignated species of the Rhodospirillaceae were examined for fumarate reduction in connection with their quinone systems. The fumarate reductase activity with reduced methyl viologen (MVH) or FMNH2 as electron donor was found in membrane (chromatophore) preparations from phototrophically grown cells of all species containing menaquinone (MK) and/or rhodoquinone. The species having ubiquinone as the sole quinone contained no fumarate reductase activity, except some Rhodobacter species showing the FMNH2-dependent activity. The MVH-fumarate reductase activity of the MK-type species was not inhibited by Triton X-100 or acetone treatment, suggesting the presence of a fumarate reductase reacting directly with MVH, while such an enzyme was absent in the MK-lacking strains, with few exceptions. The FMNH2-fumarate reduction system was abolished by a detergent or acetone extraction in all bacteria but differed much among species with different quinone types as to the response to respiratory inhibitors. These differences in fumarate-reducing properties and quinone systems among the phototrophic bacteria are discussed from evolutionary and taxonomic viewpoints.Non-standard abbreviations RQ
rhodoquinone
- MK
menaquinone
- MVH
reduced methyl viologen
- HOQNO
2-n-heptyl-4-hydroxyquinoline-N-oxide
- TTFA
2-thenoyltrifluoroacetone 相似文献
29.
Yoshiaki Fukuda Kohzoh Imai Kenju Miura Masashi Matsui Toshihiro Nakanishi Hiroshi Nakazato Johji Masukawa Toshiyuki Higashide Yuji Hinoda Teruhisa Noguchi Akira Yachi 《Cancer immunology, immunotherapy : CII》1988,27(1):26-32
Summary There have been few reports stating that monoclonal antibody alone inhibits human solid tumor growth in vivo. The present study demonstrated that monoclonal antibody S1 (IgG2a), which recognized the antigenic determinant of the carbohydrate moiety, showed antibody-dependent cell (or macrophage)-mediated cytotoxicity (ADCC or ADMC) in conjunction with murine splenocytes of both BALB/c and athymic mice. In vivo experiments demonstrated that the antibody S1 clearly prolonged the survival of athymic mice which had been inoculated with a human liver carcinoma cell line. In addition, the antibody S1 significantly suppressed the human hepatoma line transplanted s.c. into nude mice. 125I-Labeled monoclonal antibody S1 revealed that the antibody accumulated significantly in the tumor mass. Many mononuclear cells were observed surrounding tumor cells when the antibody was given. This model system might be useful for analyzing the ADCC (or ADMC) mechanism in vivo. 相似文献
30.
Yasuhiko Asada Yoshio Kimura Masaaki Kuwahara Akira Tsukamoto Kazuo Koide Atsuhiro Oka Mitsuru Takanami 《Applied microbiology and biotechnology》1988,29(5):469-473
Summary A ligninase gene has been cloned from a Phanerochaete chrysosporium genomic DNA library. Nucleotide sequencing of the gene has revealed that the ligninase structural gene contains 1116 bp of the protein-encoding sequence, of which 84 bp encode the signal peptide. The protein-encoding sequence is interrupted by eight introns which conform to the universal G-T/A-G splicing rule observed for the 3 and 5 intron boundaries. The putative eukaryotic regulatory sequences, i.e. CAAT and TATA box-like sequences, are present in the 5 flanking region. 相似文献