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81.
Monoclonal antibodies specific to a Ca2(+)-bound form of lipocortin I distinguish its Ca2(+)-dependent phospholipid-binding ability from its ability to inhibit phospholipase A2. 总被引:1,自引:0,他引:1
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H Hayashi M K Owada S Sonobe K Domae T Yamanouchi T Kakunaga Y Kitajima H Yaoita 《The Biochemical journal》1990,269(3):709-715
Lipocortin I, a Ca2(+)-and phospholipid-binding protein without EF-hand structures, has many biological effects in vitro. Its actual role in vivo, however is unknown. We obtained and characterized five monoclonal antibodies to lipocortin I. Two of these monoclonal antibodies (L2 and L4-MAbs) reacted with the Ca(+)-bound form of lipocortin I, but not with the Ca2(+)-free form, both in vivo and in vitro. Lipocortin I required greater than or equal to 10 microM-Ca2+ to bind the two antibodies, and this Ca2+ requirement was not affected by phosphatidylserine. L2-MAb abolished the phospholipase A2 inhibitory activity of lipocortin I and inhibited its binding to Escherichia coli membranes and to phosphatidylserine in vitro. L4-MAb abolished the phospholipase A2 inhibitory activity of lipocortin I, but did not affect its binding to E. coli membranes or to phosphatidylserine. These findings indicated that the inhibition of phospholipase A2 by lipocortin I was not simply due to removal or capping of the substrates in E. coli membranes. Furthermore, an immunofluorescence study using L2-MAb showed the actual existence of Ca2(+)-bound form of lipocortin I in vivo. 相似文献
82.
Hakan Cancer Nobuaki Tamamaki Uuji Handa Minoru Hayashi Yoshiaki Nojyo 《Cell and tissue research》1990,262(1):53-57
Summary Injection of wheat-germ agglutinin-horseradish peroxidase conjugate (WGA-HRP) into the superior cervical ganglion (SCG) of the rat results in accumulation of WGA-HRP in sympathetic postganglionic neurons in the contralateral SCG. The sympathetic pathways involved and the mechanism underlying the labeling were investigated. The labeling in neurons in the contralateral SCG was apparent 6 h after injection and increased in intensity with longer survival times. The number of labeled neurons reached 1300 at 72 h after the injection. Transection of the external (ECN) or internal carotid nerves (ICN) resulted in considerable reduction in the number of labeled neurons. Combined transection of both ECN and ICN virtually eliminated labeling in the contralateral SCG. This provides strong evidence that these two nerves are the major pathways for WGA-HRP transport out of the SCG. No labeling was observed in the contralateral SCG following injection of horseradish peroxidase (HRP). Therefore, it seems unlikely that a direct nerve connection exists between the bilateral ganglia. Instead, the labeling of contralateral SCG neurons appears to depend on the transneuronal transport capacity of WGA-HRP, which conveys the marker in an anterograde direction along the postganglionic fibers to terminals in sympathetic target organs, and then delivers it transneuronally to contralateral SCG neurons. We suggest that the sympathetic nerve fibers originating in the bilateral SCGs run intermingled and are in close contact in their peripheral target organs. 相似文献
83.
Hiroto Kobayashi Masako Kawasaki Hiroshi Ishizaki Ryoichi Fukushiro Ryoichi Matsumoto 《Mycopathologia》1990,112(1):19-22
A survey for the natural occurrence of Fusarium mycotoxins, deoxynivalenol (DON), nivalenol (NIV) and zearalenone (ZEN), in Dutch cereals (totaling 29 samples) harvested in 1984/1985, showed that 90%, 79% and 62% of samples were contaminated with DON, NIV and ZEN, respectively. Average contents (ng/g) in the total of positive samples were 221 (DON), 123 (NIV) and 61 (ZEN). Among the cereals examined, the highest concentrations (ng/g) was 3198 (DON), 1875 (NIV) and 677 (ZEN) in a yellow corn sample for animal feed. The results of this survey show that Dutch cereals were relatively significantly contaminated with Fusarium mycotoxins. 相似文献
84.
85.
Kiyoshi Takahashi Tadashi Yoshino Tadaatsu Akagi Katsuya Miyatani Kazuhiko Hayashi Hiroshi Sonobe Yuji Ohtsuki 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,59(1):159-164
In order to clarify the function of human S100β- positive T-cells, S100β-positive T-leukemia cells (S100β TLC) were examined in vitro. S100β TLC were obtained from the peripheral blood of a patient with S100β-positive T-cell leukemia and enriched by an E-rosetting method. Two dimensional flow cytometric analysis indicated that the
vast majority of the E-positive fraction were S100β TLC expressing CD3 and CD8 antigens. Although S100β TLC expressed CD3 antigen, they were negative for the α/β and γ/δ T-cell antigen receptor (TCR) defined by monoclonal antibodies
(mabs) WT-31 and δ TCS-1, respectively. It was speculated that S100β TLC initially expressed α/β TCR but lost it during malignant transformation. When S100β TLC were cultured for 24 h, they acquired cytotoxic activity towards various NK-sensitive cell lines including K-562, Molt-3
and CEM-CCLF, but did not exhibit lysing activity towards NK-resistant cell lines including Raji, Daudi and MT-1. Despite
the NK-activity of cultured S100β TLC, they lacked the morphological features of large granular lymphocytes (LGL). S100β TLC did not exhibit lymphokine-activated killer (LAK) activity. When S100β TLC were cocultivated with NK-sensitive cells or NK-resistant cells, they selectively bound to NK-sensitive cells, indicating
that they lysed target cells by cell-to-cell contact. The finding that S100 β TLC lacked TCR molecules and their NK activity
was not inhibited by mabs reactive with the CD3-TCR complex indicated that the CD3-TCR complex was not involved in their target
recognition. These findings suggest that S100 β-positive T-cells are functionally similar to NK cells. We discuss the roles
of S100 β-positive T-cells in the human immune system. 相似文献
86.
Masafumi Abe Naoya Nakamura Shirou Fukuhara Takamasa Hayashi Keiki Kawakami Kenkichi Kita Toshifumi Kinoshita Toyoro Ohsato Haruki Wakasa 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,59(1):107-113
A new human acute lymphoblastic leukemia (ALL) cell line, designated HBL-3, was established from the bone marrow of a patient
with non-T-ALL. The HBL-3 cell line expressed B4 (CD 19), BA-1 (CD 24) and HLA-DR antigens, but not surface immunoglobulin
(SIg) or cytoplasmic immunoglobulin (CIg). The cell line lacked the common acute lymphoblastic leukemia antigen (CALLA) and
antigenic markers characteristic of T-cell and myeloid cell lineages. The HBL-3 cells had structural rearrangements of both
the homologous chromosome 9s, including a translocation with chromosome 1 which has been reported in a patient with common
ALL. The cell line had rearranged immunoglobulin heavy chain genes but retained germ-line κ light chain genes and germ-line
T-cell receptorβ- and γ-chain genes. The HBL-3 cell line was strongly positive for terminal deoxynucleotidyl transferase (TdT). These findings
indicate that the HBL-3 cell line is derived from the earliest B-cell committed to B-cell lineage. 相似文献
87.
Hiroshi Yao Hiroaki Ooboshi Seizo Sadoshima Kentaro Takano Setsuro Ibayashi Masatoshi Fujishima 《Neurochemical research》1990,15(5):547-549
To determine the level of cerebral blood flow reduction which causes striatal dopamine release, extracellular dopamine and cerebral blood flow was simultaneously determined using in vivo brain dialysis and a hydrogen clearance method, respectively, in the striatum of spontaneously hypertensive rats, before and during experimental cerebral ischemia. The ischemic flow threshold for neurotransmitter dopamine release was found to be 20% of the resting value or 8–10 ml/100g/min of cerebral blood flow, being similar to those for energy and membrane failures. 相似文献
88.
Tatsuo Nakahara Makoto Hirano Takashi Matsumoto Toshihide Kuroki Yoshinori Tatebayashi Tetsuyuki Tsutsumi Kouji Nishiyama Hiroaki Ooboshi Kaoru Nakamura Hiroshi Yao Akio Shiraishi Michinori Waki Hideyuki Uchimura 《Neurochemical research》1990,15(6):609-611
DNA and RNA contents in 20 brain regions or nuclei of the rat were determined by a highly sensitive method using high-performance liquid chromatography with electrochemical detection. The high DNA and RNA contents were found in the hypothalamic nuclei, especially the median eminence-arcuate nucleus. These results may be available for the preparation of nucleic acids as the regional control. 相似文献
89.
Protection of mice against Sendai virus pneumonia by non-neutralizing anti-F monoclonal antibodies 总被引:1,自引:0,他引:1
Y Mochizuki T de Ming T Hayashi M Itoh H Hotta M Homma 《Microbiology and immunology》1990,34(2):171-183
Nine monoclonal antibodies (MAbs) directed to F protein of Sendai virus were obtained and characterized for their protective ability against Sendai virus infection in mice. None of the MAbs showed hemagglutination-inhibition (HI), hemolysis-inhibition (HLI), or neutralization (NT) activities in vitro when assayed by standard methods. Some of the MAbs, however, showed complement-requiring NT (C-NT) and complement-requiring hemolysis (C-HL) activities when assayed in the presence of complement. Passive immunization experiments revealed that the MAbs with higher C-NT and C-HL activities showed protective activity against Sendai virus pneumonia in mice, and that some MAbs with IgG1 isotype having neither C-NT nor C-HL activity also showed the protective activity. Digestion of the MAbs with pepsin which split immunoglobulin molecules into F(ab')2 and Fc fragments greatly suppressed the protective activity. These results suggest that not only complement-mediated immunological responses such as immune virolysis but also antibody-dependent cellular cytotoxicity (ADCC) and/or immune phagocytosis, in which complement system is not necessarily involved, play an important role in the protection of mice from Sendai virus infection. 相似文献
90.
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