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1.
Kazuhisa Toyoda Takuya Sugahara Kunio Inouye Koji Yamada Sanetaka Shirahata Hiroki Murakami 《Cytotechnology》1990,3(2):189-197
An immunoglobulin (Ig) production stimulating factor (IPSF) for hybridomas was found in spent medium of the human B lymphoblastoid cell line, HO-323. The IPSF was purified by serial use of DEAE chromatography, ultrafiltration, gel filtration and HPLC-DEAE chromatography. Purified IPSF was estimated to be a 410 k macro molecule by gel filtration, and contained three types of isomers which were separated from each other by native polyacrylamide gel electrophoresis. All of the isomers were, however, assumed to have the same protein components by SDS polyacrylamide gel electrophoresis.The IPSF was effective for human-human and mouse-mouse hybridomas producing IgM, but not for IgG producers in the experimental condition used here. Human-human hybridoma HF10B4, cultured in IPSF-containing medium, produced 20 times more IgM than in IPSF-free medium under serum-free conditions. The IPSF showed very little proliferation stimulating activity on HF10B4 cells. 相似文献
2.
We have developed a high cell density and high product concentration culture system recycling high molecular weight components. The production of monoclonal antibodies in high concentration was performed by this culture system with mouse human hybridoma H2 and V6 cells in serum-free defined media.The concentration of IgG after 48 days culture of H2 cells in ITES-eRDF reached 2 mg/ml and the purity of IgG in culture fluid was 61%. In addition, high molecular weight components in serum-free media, such as transferrin or BSA, could be reduced to 5% of the original concentration. 相似文献
3.
Tadahiro Fukiage Hiroki Murakami Masao Eura Tsutomu Ikawa Takeru Ishikawa 《Cancer immunology, immunotherapy : CII》1991,33(3):139-145
Summary Peripheral blood lymphocytes were cultured for 5 days with allogeneic tumor cells (allogeneic mixed lymphocyte/tumor cell culture), and subsequently cultured with recombinant interleukin-2 for 12 days. These cultured cells were found to be cytotoxic to autologous tumor cells. Results of two-color analysis using monoclonal antibodies to cell markers showed that more than 80% of their cultured cells were CD3+ cells, and CD4+ cells showed a higher distribution than CD8+ cells. However, CD8+ cells had a much higher killing activity with autologous tumor than did CD4+ cells, when estimated by an elimination study using monoclonal antibodies to T cell phenotypes and complement. The cold-target inhibition test showed that the cytotoxicity of these cells for autologous tumor cells was inhibited by unlabeled autologous tumor cells but not by unlabeled stimulator cells. Furthermore, about 40% of the cytotoxicity was suppressed by blocking of HLA class I antigen with a monoclonal antibody on autologous tumor cells. Thus, cytotoxic activity of lymphocytes to autologous tumor restricted by target cell HLA class I antigen is possibly induced by allogeneic tumor-stimulation. 相似文献
4.
Social changes of Japanese monkey troops in the Takasakiyama 总被引:1,自引:0,他引:1
Hiroki Mizuhara 《Primates; journal of primatology》1964,5(1-2):27-52
5.
6.
Comparison of OspA Serotypes for Borrelia burgdorferi Sensu Lato from Japan,Europe and North America
Toshiyuki Masuzawa Bettina Wilske Tetsuro Komikado Hiroyuki Suzuki Hiroki Kawabata Nanao Sato Koichi Muramatsu Nobutake Sato Emiko Isogai Hiroshi Isogai Russell C. Johnson Yasutake Yanagihara 《Microbiology and immunology》1996,40(8):539-545
Sixty-one Borrelia burgdorferi sensu lato strains from various sources (ticks, human, and wild animals) in Japan and two strains from ticks in Far Eastern Russia were classified on the basis of reactivity with 16 monoclonal antibodies (mAb) to outer surface protein A (OspA) and by DNA-DNA hybridization assay. Eleven OspA serotypes (J1 to J11) were recognized among the Japanese and the Far East Russian isolates (serotypes J1 to J9 were identified as B. garinii, serotype J10 was identified as B. afzelii, and serotype J11 corresponded to B. japonica), whereas 7 OspA serotypes for North American and European isolates previously reported (Bettina Wilske et al, J. Clin. Microbiol. 31:340-350, 1993) were not observed except for OspA serotype 2 which showed identical reactivity with OspA serotype J10. This finding provides helpful information for understanding the geographical distribution of Lyme disease borrelia and the development of vaccine and diagnostic tests. In conclusion: 1. B. burgdorferi sensu stricto has not been observed in Japan, 2. Japanese B. afzelii isolates are closely related to those from Europe, 3. B. garinii isolates from Japan are highly heterogeneous and apparently different from European B. garinii isolates. 相似文献
7.
Yoshihito Shirai Masaaki Yamaguchi Atsuko Kobayashi Akihiro Nishi Hisao Nakamura Hiroki Murakami 《Cytotechnology》1994,14(2):129-146
The growth yields for glucose and glutamine of murine hybridoma cells entrapped in collagen gel particles were examined during the growth phase. The immobilized hybridoma cells were cultivated in a fluidized bed fermenter where the medium was circulating to supply oxygen separately. Procedures to supply an alkaline solution for adjusting the pH level strongly affected the growth yields. A direct supply of the alkaline solution to the cultivation system reduced both the growth yields for glucose and glutamine, probably due to a local increase in pH level. On the other hand, when fresh medium in which the pH was adjusted to around 8.5 was added to the cultivation system, the growth yields were unchanged even at the same pH level as when direct alkaline supply was used. These results suggest that an indirect alkaline supply could be recommended to ajust the pH level when using medium-circulating-fermenters. 相似文献
8.
The anatomical framework of the jawbones is highly conserved among most of the Osteichthyes, including the tetrapods. However, our recent study suggested that the premaxilla, the rostralmost upper jaw bone, was rearranged during the evolution of therian mammals, being replaced by the septomaxilla at least in the lateral part. In the present study, to understand more about the process of evolution from the ancestral upper jaw to the therian face, we re-examined the development of the therian premaxilla (incisive bone). By comparing mouse, bat, goat, and cattle fetuses, we confirmed that the therian premaxilla has dual developmental origins, the lateral body and the palatine process. This dual development is widely conserved among the therian mammals. Cell-lineage-tracing experiments using Dlx1-CreERT2 mice revealed that the palatine process arises in the ventral part of the premandibular domain, where the nasopalatine nerve distributes, whereas the lateral body develops from the maxillary prominence in the domain of the maxillary nerve. Through comparative analysis using various tetrapods, we concluded that the palatine process should not be considered part of the ancestral premaxilla. It rather corresponds to the anterior region of the vomerine bone of nonmammalian tetrapods. Thus, the present findings indicate that the true premaxilla was completely lost during the evolution of the therian mammals, resulting in the establishment of the unique therian face as an evolutionary novelty. Reconsideration of the homological framework of the cranial skeleton based on the topographical relationships of the ossification center during embryonic development is warranted. 相似文献
9.
Yohji Esashi Shinichi Matsuyama Hiroki Ashino Maria Ogasawara Ryo Hasegawa 《Physiologia plantarum》1991,83(1):34-40
In many seed species, the major source of HCN evolved during water imbibition is cyanogenic glycosides. The present investigation was performed to elucidate the role of endogenous cyanogenic glycosides in the control of seed germination and to examine the involvment of β-glucosidase in this process. All seed species used here contained some activities of β-glucosidase already in the dry state before imbibition. in the decreasing order of Malus pumila, Daucus carota, Hordeum vulgare, Chenopodium album and so on. β-Gluosidase activity in upper and lower seeds of cocklebur (Xanthium pennsylvanicum Wallr.) decreased with imbibition, and in lower seeds the activity disappeared when they germinated. On the contrary, in caryopses of rice (Oryza sativa L. cv. Sasanishiki) β-glucosidase increased during imbibition, and this increase continued even after germination. β-Glucosidase in cocklebur seeds was more active in the axial than in the cotyledonary tissue. Amygdalin, prunasin and linamarin could all serve as substrattes for the β-glucosidase(s) from both cocklebur and rice. Amygdalin, prunasin and linamarin as well as KCN, were effective in stimulating the germination of upper cocklebur seeds. The seeds evolved much more free HCN gas when they were exposed to the cyanogenic glycosides than when the glycosides were absent. Moreover, the application of the cyanogenic glycosides or of KCN caused accumulation of bound HCN in the seeds. Carbon monoxide, which stimulated cocklebur seed germination only slightly, did not cause accumulation of bound HCN. We suggest that a balance between the cytochrome and the alternative respiration pathways, which is adequate for germination (Esashi et al. 1987. Plant Cell Physiol. 28: 141–150), may be brought about by the action of endogenous HCN; a large portion of which is liberated from cyanogenic glycosides via the action of β-glucosidase. In addition to the partial suppression of the cytochrome path and unlike carbon monoxide, the HCN thus produced may act to supply cyanide group(s) to unknown compounds necessary for germination. 相似文献
10.
Theoretical results on the geometric and electronic structures of some donor-acceptor polymers based on polythiophene (X=S), polyfuran (X=O) and polypyrrole (X=NH) were obtained, using a one-dimensional tight-binding self-consistent field crystal-orbital (SCF-CO) method at the MNDO-AM1 level of approximation. The repeat unit of these polymers consits of a bithiophene, furan or bipyrrole unit bridged by an electron-accepting group or. The optimized geometries of the polymers show a strong dependence on the nature of the electron donating group X. All the polymers studied are predicted to have band gap values ranging between 1 eV and 2 eV. An analysis of their -bond order data and of the patterns of their frontier orbitals shows they have benzenoid-like electronic structures. 相似文献