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Hitoshi Kakidani Shinobu Watarai Misao Onuma Ken-ichi Tomochika Tatsuji Yasuda 《Microbiology and immunology》1993,37(9):713-720
A recombinant plasmid which contained a gene for diphtheria toxin A-chain (DT-A) under the control of the long terminal repeat (LTR) of bovine leukemia virus (BLV) (BLV-LTR) was constructed to test a novel application of liposomes as antiviral agents. The promoter activity of BLV-LTR was estimated by the chloramphenicol acetyltransferase (CAT) assay using a plasmid which contains the coding sequence of CAT under the control of BLV-LTR (pBLVCAT). When BLV-infected cells were transfected with pBLVCAT, CAT activity was detected. BLV-uninfected cell lines, however, showed no detectable CAT activity. The plasmid DNA entrapped in liposomes was added to BLV-infected cells in culture. Syncytium formation induced by BLV-infected cells was effectively suppressed by the liposomes containing the gene for DT-A under the control of BLV-LTR. Conversely, liposomes containing the gene for DT-A without a promoter showed no such effect. DT-A gene-containing liposomes with BLV-LTR did not affect formation of syncytium induced by bovine immunodeficiency virus. These observations indicate that BLV-infected cells were readily targeted on the level of gene expression. This strategy could be applied to the treatment of BLV-induced B-cell proliferation of cattle, and further to other viral/neoplastic diseases where specific gene expression is exerted. 相似文献
24.
V. Collura J. Higo J. Garnier 《Protein science : a publication of the Protein Society》1993,2(9):1502-1510
A method is presented to model loops of protein to be used in homology modeling of proteins. This method employs the ESAP program of Higo et al. (Higo, J., Collura, V., & Garnier, J., 1992, Biopolymers 32, 33-43) and is based on a fast Monte Carlo simulation and a simulated annealing algorithm. The method is tested on different loops or peptide segments from immunoglobulin, bovine pancreatic trypsin inhibitor, and bovine trypsin. The predicted structure is obtained from the ensemble average of the coordinates of the Monte Carlo simulation at 300 K, which exhibits the lowest internal energy. The starting conformation of the loop prior to modeling is chosen to be completely extended, and a closing harmonic potential is applied to N, CA, C, and O atoms of the terminal residues. A rigid geometry potential of Robson and Platt (1986, J. Mol. Biol. 188, 259-281) with a united atom representation is used. This we demonstrate to yield a loop structure with good hydrogen bonding and torsion angles in the allowed regions of the Ramachandran map. The average accuracy of the modeling evaluated on the eight modeled loops is 1 A root mean square deviation (rmsd) for the backbone atoms and 2.3 A rmsd for all heavy atoms. 相似文献
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Isolation and Characterization of Hardening-Induced Proteins in Chlorella vulgaris C-27: Identification of Late Embryogenesis Abundant Proteins 总被引:4,自引:0,他引:4
Honjoh Ken-ichi; Yoshimoto Makoto; Joh Toshio; Kajiwara Taishin; Miyamoto Takahisa; Hatano Shoji 《Plant & cell physiology》1995,36(8):1421-1430
Hardening-induced soluble proteins of Chlorella vulgaris BeijerinkIAM C-27 (formerly Chlorella ellipsoidea Gerneck IAM C-27) wereisolated and purified by two-dimensional high-performance liquidchromatography (2D-HPLC) on an anion-exchange column, with subsequentreversed-phase chromatography. Some of the proteins were resolvedby SDS-PAGE, characterized by amino-terminal sequencing andidentified by searching for homologies in databases. Separationof the soluble proteins during the hardening of Chlorella bya combination of 2D-HPLC and SDS-PAGE revealed that at least31 proteins were induced or increased in abundance. Of particularinterest was the induction after 12 h of a 10-kDa protein withthe amino-terminal amino acid sequence AGNKPITEQISDAVGAAGQKVGand the induction after 6 h of a 14-kDa protein with the amino-terminalsequence ALGEESLGDKAKNAFEDAKDAVKDAAGNVKEAV. The amino-terminalsequences of these proteins indicated that they were homologousto late embryogenesis abundant (LEA) proteins. Furthermore,the level of a 22-kDa protein also increased after 12 h. Theamino-terminal sequence of this protein, AAPLVGGPAPDFTAAAVFD,indicated that it was homologous to thioredoxin peroxidase. (Received June 9, 1995; Accepted September 12, 1995) 相似文献
27.
Nishijima K Hisatsune T Kato H Kohyama M Kakehi M Hachimura S Kaminogawa S 《Cytotechnology》1997,25(1-3):89-100
Feeding of a whole casein diet, which abolished the αs1-casein-specific proliferation and IFN-γ productivity of CD4+ T cells, did not affect the proliferative response of CD8+ T cells with regard to the antigen dose response, cell dose response, kinetics of the proliferation and epitope specificity,
as well as IFN-γ production. To assess the characteristics of the CD8+ T cells, we established αs1-casein-specific CD8+ T cell clones from both casein-fed and control mice. The established clones produced different amount of IFN-γ and IL-10,
and one clone derived from the casein-fed mice produced a remarkable amount of IL-10. The clones from casein-fed mice produced
considerable amounts of TGF-β, while those from control mice produced only small amounts. The possible role of CD8+ T cells in oral tolerance is discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
28.
N. Ohmiya Shinsuke Saga Masaharu Ohbayashi Ken-ichi Kozaki Osamu Miyaishi Miya Kobayashi Shiro Kasuya Tomiyasu Arisawa Hidemi Goto Tetsuo Hayakawa 《Histochemistry and cell biology》1997,108(1):27-34
An association between eosinophils and tissue damage has been observed in numerous disorders. However, few reports have addressed
the role of infiltrating eosinophils in gastric ulcer healing. The aim of this study was to investigate the kinetics and role
of eosinophils infiltrating experimental chronic gastric ulcers in the rat. We developed a monoclonal antibody against human
matrix metalloproteinase 1 (MMP1) purified from conditioned culture medium of human skin fibroblasts. Acetic acid-induced
gastric ulcers were resected from rats on days 1, 3, 5, 10, 20, 40, and 180 after the days of induction (day 0). Tissue specimens
were immunostained with this antibody and examined with an electron microscope. Few eosinophils were observed in the granulation
tissue until day 20. By days 40 and 180, MMP1-positive eosinophils had increased in the granulation tissue of open ulcers.
Azan staining revealed dispersed collagen fibers around infiltrating eosinophils. In contrast, scars demonstrated few eosinophils
in fibrous tissue on days 40 and 180. Eosinophils which express MMP1 infiltrate granulation tissue at the chronic stage of
gastric ulceration. The results suggest that eosinophils may play a role in tissue remodeling and deterioration of ulceration.
Accepted: 18 March 1997 相似文献
29.
Changes in the pattern of soluble proteins that accumulatedat the growth phase, interphase and late-aggregation phase ofthe cellular slime mold Dictyostelium discoideum were studiedby two-dimensional polyacrylamide gel electrophoresis. Amongthe 300 proteins detected during the early development, themost soluble do not change during the growth and aggregationphases, but about 90 proteins show changes in their relativeintensities on staining. During the transition from growth tothe interphase, the predominant changes were the disappearanceof 16 spots, the decrease in 30 spots, the appearance of 13new spots, and the increase in 14 spots. In contrast, from theinterphase to the late-aggregation phase, there were remarkableprogressive increases in 13 spots, an overall increase in 6spots, a decrease in 16 spots, the appearance of 8 new spotsand the disappearance of 4 spots. (Received July 13, 1979; ) 相似文献
30.
Kohei Kawashima Eiji Watanabe Ken-ichi Isobe Michinori Ogura Ei-ichi Nagura Kazumasa Yamada Itsuro Sobue Kenji Mizoguchi Yasuhiko Ito Yoshiyuki Nagai Izumi Nakashima 《Cellular immunology》1982,67(2):279-286
During the course of immunization of (C3H × DBA/2)F1 mice (genotype H-2k/b) with L cell (H-2k/k)/L1210 leukemia cell (H-2d/d) hybrids and L1210 leukemia cells, some of them produced a good titer of anti-self-H-2 (H-2d) antibodies. Antigens recognized by this anti-self-H-2 antiserum were shown to be controlled by the H-2K-IA-IB-IJ-IE subregions of the H-2d but not H-2k nor H-2b haplotypes of parental as well as F1 origins and to have a tissue distribution identical to that of class 1 H-2 (H-2K/D) antigens. 相似文献