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101.
102.
Akira Yamada Masaaki Murakami Kenichi Ijima Hideo Yagita Ko Okumura Sakuzo Komatsu Toshimitsu Uede 《Microbiology and immunology》1996,40(7):513-518
The immunosuppressant FK506 prolongs allograft survival. However, at therapeutic doses it has significant side effects. A fusion protein consisting of the extracellular portion of CTLA4 and the Fc portion of human IgG (CTLA4IgG) also prolongs allograft survival, but large doses of CTLA4IgG are required for the induction of cardiac allograft acceptance. Therefore, we constructed a pentameric form of a new CTLA4 fusion protein, CTLA4IgM. We tested whether low doses of CTLA4IgG or CTLA4IgM in combination with subtherapeutic doses of FK506 can prolong allograft survival in a synergistic fashion. C57BL/6 (H-2b) neonatal hearts were transplanted to CBA/J (H-2k) mice in a heterotopic, nonvascularized cardiac allograft model. The findings demonstrate that a combination of low doses of FK506 plus a pentameric form of CTLA4Ig, CTLA4IgM, leads to significant graft survival, while a combination of FK506 plus CTLA4IgG does not. 相似文献
103.
M. Sunairi N. Iwabuchi K. Murakami F. Watanabe Y. Ogawa H. Murooka M. Nakajima 《Letters in applied microbiology》1996,22(1):66-69
M. SUNAIRI, N. IWABUCHI, K. MURAKAMI, F. WATANABE, Y. OGAWA, H. MUROOKA AND M. NAKAJIMA. 1996. Suitable conditions for the introduction of bacteriophage DNA into cells of Rhodococcus rhodochrous CF222 by electroporation were established, and penicillin G was found to enhance the transfection frequency. When conditions optimal for the parental strain were applied to its colony-morphological mutants, different transfection frequencies were observed. Penicillin G enhanced the transfection frequency of smooth and mucoidal mutants but not of rough mutants. 相似文献
104.
105.
106.
Takeuchi Yuichi; Murakami Mina; Nakajima Nobuyoshi; Kondo Noriaki; Nikaido Osamu 《Plant & cell physiology》1996,37(2):181-187
Photoinduced lesions in DNA, namely, cyclobutane pyrimidinedimers (CPDs) and pyrimidine-(6-4)-pyrimidone photoproducts[(6-4)photoproducts], in cucumber cotyledons that had been irradiatedwith naturally occurring levels of UV-B (290320 nm) werequantitated by enzyme-linked immunosorbent assays with monoclonalantibodies specific to each type of photolesion. Induction ofthese photolesions was dependent on temperature and their extentwas reduced by simultaneous irradiation with white light. Thedark repair of both types of photolesion was undetectable. Light-dependentremoval of (6-4)photoproducts was very slow, with 50% removalin 4 h. By contrast, 50% of initial CPDs were removed within15 min. Both photorepair processes were dependent on the intensityof white light and were sensitive to temperature. These resultsindicate that high photolyase activity is present in cucumbercotyledons and that repair activities in cucumber cotyledonsare different from those reported in Arabidopsis, in which (6-4)photoproductsare photorepaired more rapidly than CPDs. (Received October 13, 1995; Accepted December 28, 1995) 相似文献
107.
For the advancement of Human Genome Project, we have developed an automated DNA sequencing system HUGA-I. It is composed of several automated instruments and transfer robots connecting them. In this paper we describe the results of the performance evaluation test of HUGA-I. Although some of the system units showed good performances, the total performance of the HUGA-I was about 1/6 of the designed value. By revealing principal reasons of this poor performance, we would like to contribute to the automation in genome analysis, particularly in human genome analysis.Since the sequence technology advanced remarkably in these years, the system units of HUGA-I become older than those which are now commercially available and the throughput of it is out of our expectations. Nevertheless, we believe that it is meaningful to introduce the exact performance of HUGA-I and present the bottle neck points in the automating sequencing processes. Because, automation in the gene analysis is ultimately important, in particular for the analysis of large genomes such as the human genome. The aims of this paper are to introduce the results in performance evaluation of HUGA-I and to elucidate the bottle neck points in the automation of sequencing processes.The authors express their sincere thanks to Mr. Morisada Hayakawa and Mrs. Nobuko Kato for their technical asistance. 相似文献
108.
Tatsuo Kawarasaki Tetsuya Kohsaka Masaru Sone Mitsutoshi Yoshida Kimio Bamba 《Molecular reproduction and development》1995,40(4):455-459
This study was carried out to determine whether Y-bearing porcine spermatozoa could be detected by in situ hybridization using a digoxigenin (Dig)-labelled DNA probe specific to the Y chromosome produced by polymerase chain reaction (PCR). A conventional PCR (with Dig-dUTP) was performed using a set of oligonucleotide primers (5′-AAGTGGTCAGCGTGTCCATA-3′ and 5′-TTTCTCCTGTATCCTCCTGC-3′) for 236 bp fragment of porcine male-specific DNA sequence and 1.25 × 104 template white blood cells obtained from a boar. When fluorescence in situ hybridization with the Dig-labelled DNA probe was applied to the metaphase chromosome spreads prepared from both boar and gilts, the fluorescein signal was only detected on the long arm of the Y chromosome. In addition, immunocytochemical detection with the Dig-labelled DNA probe and alkaline phosphatase-labeled anti-Dig was applied to both sperm nuclei pretreated with dithiothreitol and white blood cells; 51% of sperm nuclei and 96% of white blood cells obtained from boar were labelled, whereas none of white blood cells obtained from gilts were labelled with the Dig-labelled DNA probe. The results indicated that in situ hybridization with porcine male-specific DNA probe produced by PCR made possible the direct visualization of Y-bearing porcine spermatozoa by in situ hybridization. © 1995 Wiley-Liss, Inc. 相似文献
109.
A Mucor pusillus mutant defective in asparagine-linked glycosylation was found in our stock cultures. This mutant, designated 1116, secreted aspartic proteinase (MPP) in a less-glycosylated form than that secreted by the wild-type strain. Analysis of enzyme susceptibility, lectin binding, and carbohydrate composition indicated that this mutant secreted three glycoforms of MPPs, one of which contained no carbohydrate; the other two had truncated asparagine-linked oligosaccharide chains such as Man0-1GlcNAc2. Further analysis using oligosaccharide processing inhibitors, such as castanospermine, 1-deoxynojirimycin and N-methyldeoxynojirimycin, suggested that MPPs in the mutant were glycosylated through a transfer of the truncated lipid-linked oligosaccharides, Man0-1GlcNAc2, to the MPP protein but not through an aberrant processing. In addition, genetic studies with forced primary heterokaryons indicated that the mutation in strain 1116 was recessive. 相似文献
110.
Shukuro Araki Shigehiro Yi Tatsufumi Murakami Susumu Watanabe Shinichi Ikegawa Kiyoshi Takahashi Ken-ichi Yamarnura 《Molecular neurobiology》1994,8(1):15-23
To analyze the pathologic processes of amyloid deposition in type I familial amyloidotic polyneuropathy (FAP), mice were made
transgenic by introducing the human mutant transthyretin (TTR) gene(MT-hMet 30). An inbred strain of mouse, C57 BL/6, was
chosen. Transgenic mice were killed using ether anesthesia at 3-mo intervals up to 24 mo after birth. In these transgenic
mice, amyloid deposition started in the gastrointestinal tract, cardiovascular system, and kidneys and extended to various
other organs and tissues with advancing age. The pattern of amyloid deposition was similar to that observed in human autopsy
cases of FAP, except for its absence in the choroid plexus and in the peripheral and autonomic nervous systems.
We extracted the amyloid fibrils from kidneys of these mice with a human mutant TTR gene and analyzed them immunochemically
and electronmicroscopically. Deposited amyloid was shown to be composed of human mutant TTR and mouse serum amyloid P component.
Amyloid fibril from transgenic mice was morphologically and immunohistochemically similar to that of human FAP.
The most striking pathologic feature of the transgenic mice was the absence of amyloid deposition in the peripheral and autonomic
nervous tissues. Thus, other intrinsic factors may be involved in amyloid deposition in the nervous tissues of human FAP. 相似文献