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1.
Shigeki Takeura Hiizu Aoki Tatsuya Tsurumi Yukihiro Nishiyama Hisashi Fujioka Saiji Yoshii Koichiro Maeno 《Microbiology and immunology》1984,28(4):427-437
Host-dependent restriction of influenza B virus replication in L cells was analysed in comparison with productive infection in MDCK or 1–5C-4 cells. The synthesis and intracellular distribution of virus-specific proteins and the production of cytoplasmic ribonucleoproteins in nonpermissive L cells were similar to those in permissive MDCK cells. However, an electron microscopic study of infected L cells showed neither extracellular virions nor budding virus particles on the cell surface, in contrast to MDCK cells which produced numerous virus particles. PAGE analysis of the plasma membrane isolated from the cells demonstrated no significant difference in the composition of viral polypeptides between permissive 1-5C-4 and nonpermissive L cells. It was noted that the abortiveness of influenza B virus infection in L cells may be due to a defect in host cell function involved in the initiation of virus budding. 相似文献
2.
3.
M Hiramatsu M Kashimata N Minami A Sato M Murayama N Minami 《Biochemistry international》1988,17(2):311-317
Castration of adult male mice caused a marked reduction in the amount of immunoreactive epidermal growth factor (EGF) in the ventral prostate, and the treatment of such castrated mice with testosterone increased the EGF level significantly. Gel filtration of prostate extract showed that the immunoreactive EGF in the prostate had the same molecular weight (6,045) as the submandibular gland EGF. Moreover, its isoelectric point (pH 4.5) was almost similar to that (pH 4.55) of the submandibular gland peptide. These results suggest that under the control of androgens, mouse ventral prostate synthesizes EGF structurally and functionally identical to the submandibular gland EGF. 相似文献
4.
Indu S. Ambudkar Timothy Lockwich Yukiharu Hiramatsu Bruce J. Baum 《Molecular and cellular biochemistry》1992,114(1-2):73-77
Conclusions While it is generally accepted that Ca2+ plays an important regulatory role in the physiology of a number of non-excitable cells, the mechanisms which regulate intracellular [Ca2+ are far from well established. Ca2+ transporting mechanisms which distribute Ca2+ intracellularly as well as those which allow influx of extracellular Ca2+ are involved in mediating intracellular Ca2+ homestasis. In this paper we have described recent studies on the regulation of the Ca2+ influx system in the data, it appears that the process of Ca2+ entry is extremely complex and may involve several levels of regulation. Understanding the molecular basis of these regulatory mechanisms presents a challeging problem for future studies. 相似文献
5.
Ayumi Ohsaki Yoshihisa Kasetani Yukihiro Asaka Kozo Shibata Takashi Tokoroyama Takashi Kubota 《Phytochemistry》1991,30(12):4075-4077
Three trans-clerodane diterpenoids, pilosanol A, B and C, the last compound being a glucoside, have been isolated from the roots of Portulaca pilosa. They show a marked contrast in skeletal type with the constituents of aerial part. Evolutionary changes in the biosynthetic abilities of Portulaca species is discussed. 相似文献
6.
Effects of cytokines on in vitro growth of tumor-infiltrating lymphocytes obtained from human primary and metastatic liver tumors 总被引:4,自引:0,他引:4
Yukihiro Shimizu Shunzaburo Iwatsuki Ronald B. Herberman Theresa L. Whiteside 《Cancer immunology, immunotherapy : CII》1991,32(5):280-288
Summary Tumor-infiltrating lymphocytes (TIL) were isolated from 22 human primary and metastatic liver tumors, and expanded in vitro in the presence of either interleukin-2 (IL-2, 100 U/ml) plus tumor necrosis factor (TNF, 1000 U/ml), IL-2 (1000 U/ml) plus IL-4 (1000 U/ml) or IL-2 (1000 U/ml) alone. TIL proliferated in culture in 20/22 cases. Among different cytokine combinations, TNF and IL-2 were most effective in promoting the outgrowth of CD3+ CD8+ T lymphocytes (mean ± SEM: 90%±5) in the cultures of TIL from primary liver tumors. Cytotoxicity against autologous tumor cells was demonstrated in all early cultures of TIL from primary liver cancers in the presence of IL-2 plus TNF. In contrast, cultures of TIL derived from colon cancer metastatic to liver had significantly lower levels of autotumor cytotoxicity and proportions of CD3+ CD8+ cells (40%±13) than those of TIL from primary liver tumors. The addition on day 0 of interferons ( or ) to TIL cultured in the presence of TNF and IL-2, significantly augmented cytotoxicity against autologous tumor. In contrast, incubation of TIL in the presence of IL-4 and IL-2 did not result in increased autotumor responses in the cultures of TIL from primary liver tumors. The expansion (-fold) of TIL (day 30) cultured in the presence of IL-2 alone compared to that in the presence of TNF and IL-2 was significantly greater for hepatocellular carcinoma (median, 280 vs 260) than for autologous peripheral blood lymphocytes (36 vs 27), cholangiocarcinoma (42 vs 51) or TIL from metastatic colon cancer (39 vs 30). Outgrowth of TIL in IL-2 plus TNF offers an opportunity for in vitro enrichment in cells with autotumor cytotoxicity in primary liver tumors. However, this cytokine combination was unable to promote and sustain growth of autotumor effectors from TIL in metastatic liver cancer.Supported by ACS grants IM27 077 and IM588 A (TLW) and Organ Transplant Program Project 1P01-CA-4744501 AZ 相似文献
7.
K Hiramatsu A Chait E L Bierman 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1985,180(1):9-16
Secretory products of freshly isolated human circulating blood cells such as platelets, monocytes, and B lymphocytes, but not T lymphocytes, have previously been shown to enhance low density lipoprotein (LDL) metabolism by arterial wall cells. This study was undertaken to evaluate how secretory factor(s) from mononuclear cells that had been stimulated by concanavalin A (Con A) alters LDL receptor activity by cultured human skin fibroblasts. Conditioned medium from Con A-stimulated mononuclear cells produced an increase of 125I-LDL degradation accompanied by increased thymidine incorporation into DNA. The effect of conditioned medium from the Con A-stimulated mononuclear cells was mediated by the LDL receptor pathway. Degradation of HDL and methylated LDL, neither of which is taken up by the classical LDL receptor pathway, was not affected. The conditioned medium from these Con A-stimulated cells also failed to stimulate fluid pinocytosis, as measured by the uptake of [14C]sucrose. Some strains of fibroblasts, deficient in LDL receptors, responded to the conditioned medium from the Con A-stimulated mononuclear cells by increasing the very small amounts of LDL degraded by these cells. Fibroblasts from other homozygous familial hypercholesterolemic cell strains were unresponsive, however. The effect on LDL receptors was characterized by an increase in LDL receptor number without a change in the affinity of LDL for its receptor. Thus stimulated mononuclear cells secrete mitogens that also stimulate LDL receptor activity in human skin fibroblasts. 相似文献
8.
Molecular cloning of cDNA coding for human preprourokinase 总被引:2,自引:0,他引:2
A cDNA library was constructed in pBR322 from 18S to 20S mRNA that was extracted from human kidney cells, fractionated on oligo(dT)-cellulose column and sucrose-density gradient, and confirmed for urokinase production in Xenopus laevis oocytes. The Escherichia coli RR1 transformants were hybridized to synthetic oligonucleotide probe prepared according to the known amino acid sequence, Glu 73 to Glu 77 of human urinary urokinase chain B. The entire cloned cDNA covers a 2250-bp region, wherein the 1293-bp sequence codes for preprourokinase consisting of 431 amino acids, with the first 20 residues being a signal peptide. The 5'-untranslated region is at least 80 bp long and the 3'-untranslated region is longer than 850 bp. 相似文献
9.
Sumitomo Shinichiro Tatemoto Yukihiro Fukui Shin Nakamura Taka-aki Fukushima Shoji Ito Nobuyuki Mori Masahiko 《Virchows Archiv. B, Cell pathology including molecular pathology》1985,49(1):395-399
Virchows Archiv B Cell Pathology - Paget cells from cases of mammary and extramammary Paget’s disease were examined for carcinoembryonic antigen (CEA) and CEA-related antigens by the... 相似文献
10.
Masami Matsumoto Yukihiro Shoyama Itsuo Nishioka Hisashi Iwai Satoshi Wakimoto 《Plant cell reports》1989,7(8):636-638
Virus free plants of Rehmannia glutinosa Libosch. var. purpurea Makino were obtained through meristem tip tissue cultures from plants infected with a mixture of tabocco mosaic virus(TMV), a member of the carlavirus group, and an unknown spherical virus. The re-infection rate of the virus free plants by TMV in the field was determined by enzyme linked immunosorbent assay(ELISA). Twenty seven percent of the plants were re-infected during the first year, 31 % by the end of second year, and 63 % by the end of the third year. The yield of root and iridoid glycoside contents gradually decreased each year. These results led to the conclusion that virus infection causes marked decrease of the yield of roots and productivity of secondary metabolites. 相似文献