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91.
Takashi Saito Kensuke Futatsugi Daisuke Miki Hiroshi Suzuki Kiyoshi Yasukawa 《Biotechnology Techniques》1992,6(4):365-370
Summary Murine interleukin-6 (mIL-6) was expressed inEscherichia coli as human growth hormone (hGH) fusion protein. The products were cleaved by thrombin to liberate mIL-6. Monoclonal and polyclonal
antibodies specific to mIL-6 were prepared by immunizing rats with mIL-6 thus obtained. ELISA for the quantitation of mIL-6
was also established, which could detect mIL-6 in a quantity as low as 2 ng/ml. 相似文献
92.
Endo S Inada K Inoue Y Otsu T Kasai T Kuwata Y Hoshi S Yoshida M 《Mediators of inflammation》1992,1(1):45-48
Plasma levels of endotoxin and various cytokines were assessed in 70 patients with gastrointestinal tract perforation. Sepsis developed in 29 of them, and eight of these (27.6%) had on admission endotoxin levels higher than 9.8 pg ml(-1). The clinical outcome correlated with the level of tumour necrosis factor alpha (TNFalpha), rather than with the endotoxin level. The high interleukin 6 (IL-6) level was shown in septic patients and no correlation was observed between the IL-6 level and the clinical outcome. Plasma TNFalpha levels tended to change independently from endotoxin levels, suggesting that TNFalpha may have been locally produced in inflammatory lesions. 相似文献
93.
Michiaki Morohashi Keiko Tsuchiya Takashi Mita Masaru Kawamura 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1991,161(1):69-72
Summary An inhibitory activity to (Na,K)ATPase was found in cell extracts of the brine shrimp, Artemia salina, irrespective of its developmental stages. Organic solvent extraction together with gas chromatographic analysis reveals that the inhibitory activity is due to long-chain, non-esterified fatty acids and their derivatives. Unsaturated fatty acids, especially with cis-configuration, are more effective in inhibition than saturated ones.Abbreviations ATPase
adenosine triphosphatase
- EDTA
ethylenediamine-tetraacetate
- TLC
thin-layer chromatography 相似文献
94.
The mutant c-fgr protein (p58c-fgr/F523) containing Phe-523 instead of Tyr-523 exhibited transforming activity in NIH 3T3 cells like other protein-tyrosine kinases of the src family, but normal p58c-fgr (p58c-fgr/wt) did not. The mutant protein showed tyrosine kinase activity threefold higher than that of the normal protein in vitro. Surprisingly, transfection of the normal c-fgr gene into NIH 3T3 cells resulted in induction of sodium fluoride (NaF)-sensitive alpha-naphthyl butyrate esterase (alpha-NBE), a marker enzyme of cells of monocytic origin, which was not induced in v-src-, v-fgr-, or lyn-transfected NIH 3T3 cells. The NaF-sensitive alpha-NBE induced in c-fgr transfectants was shown by isoelectric focusing to have a pI of 5.2 to 5.4, a range which was the same as those for thioglycolate-induced murine peritoneal macrophages and 1 alpha,25-dihydroxyvitamin D3-treated WEHI-3B cells. Immunoblotting studies with antiphosphotyrosine antibodies revealed that 58-, 62-, 75-, 120-, 200-, and 230-kDa proteins were commonly phosphorylated at tyrosine residues in NIH 3T3 cells transfected with normal and mutated c-fgr, while 95-kDa protein was significantly phosphorylated at tyrosine residues in cells transfected with the mutated c-fgr. These findings suggest that tyrosine phosphorylation of specific cellular substrate proteins is important in induction of NaF-sensitive alpha-NBE and cell transformation by p58c-fgr. 相似文献
95.
Primary cultures of neonatal cardiac myocytes were used to determine the effects of tumor-promoting phorbol esters on ribosomal RNA (rRNA) synthesis during myocyte growth. Treatment of myocytes with phorbol-12,13-dibutyrate (PDBu) increased protein accumulation by 25% and RNA content by 20%. Rates of rRNA synthesis were measured to assess the mechanism by which rRNA accumulated during myocyte growth. Rates of rRNA synthesis were determined from the incorporation of [3H]uridine into UMP of purified rRNA and the specific radioactivity of the cellular UTP pool. After 24h of PDBu treatment, cellular rates of 18S and 28S rRNA synthesis were accelerated by 67% and 64%, respectively. The increased rate of rRNA synthesis accounted for the net increase in myocyte rRNA content after PDBu treatment. 相似文献
96.
Summary An immunohistochemical study of the production of the intermediate filaments [vimentin, cytokeratin, and glial filament acidic protein (GFAP)] during development of the pituitary gland was made by use of fetal and adult human pituitary tissue. Among these intermediate filament proteins in the anterior and intermediate lobes of the pituitary, cytokeratin is the first to appear, followed by GFAP and vimentin. However, only cytokeratin is seen during the period of morphogenesis of the pituitary gland, with the type-II subfamily cytokeratin 8 being the earliest to appear. Among the simple-epithelial-type cytokeratins, cytokeratins 8 and 19 were observed within the pituitary primordium during morphogenesis. Cells immunoreactive for cytokeratins 8 and 19 showed a heterogeneous three-dimensional distribution pattern in Rathke's pouch. Both cytokeratins 8 and 19 tended to be strongly positive at sites in the pituitary primordium where cells had become more loosely arranged (i.e., areas far from the diencephalon) but were only weakly positive in areas in which the epithelial cells were densely packed (i.e., areas closely associated with the diencephalon). It is concluded that, during the period of morphogenesis, Rathke's pouch has the intermediate filaments characteristic of simple epithelium and shows different immunoreactivity for simple-epithelial-type cytokeratins from place to place according to the extent of cellular differentiation. 相似文献
97.
Teruo Okasora Mitsumasa Nagase Hiroshi Kawachi Katsuyuki Matsui Michiaki Orikasa Tetsuo Morioka Ichiroh Yamazaki Takashi Oite Fujio Shimizu 《Virchows Archiv. B, Cell pathology including molecular pathology》1991,60(1):41-46
Change in the localization of the antigen recognized by the proteinuria-inducing monoclonal antibody (MA) 5-1-6 in experimental nephrosis was studied by indirect and biotin-avidin immunofluorescence, and immunoperoxidase at light and electron microscopical levels. The proteinuric state was induced by the administration of the aminonucleoside of puromycin (PAN) or adriamycin. The antigen decreased in quantity and/or its distribution changed with an increase in the amount of protein excreted in both experimental models. Recovery from the alterations observed during the development and proteinuria appeared to occur when PAN-induced proteinuria subsided. This antigenic molecule may thus be essential for maintaining the normal permselectivity of glomerular capillary walls. 相似文献
98.
Michael I. Lerman Farida Latif Gladys M. Glenn Lambert N. Daniel Hiltrud Brauch Shigeto Hosoe Krista Hampsch John Delisio Mary Lou Orcutt O. Wesley McBride Karl-Heinz Grzeschik Takashi Takahashi John Minna Patrick Anglard W. Marston Linehan Berton Zbar 《Human genetics》1991,86(6):567-577
Summary A collection of 2,000 lambda phage-carrying human single-copy inserts (> 700 bp) were isolated from two chromosome-3 flow-sorted libraries. The single-copy DNA fragments were first sorted into 3p and 3q locations and about 700 3p fragments were regionally mapped using a deletion mapping panel comprised of two humanhamster and two-human-mouse cell hybrids, each containing a chromosome 3 with different deletions in the short arm. The hybrids were extensively mapped with a set of standard 3p markers physically localized or ordered by linkage. The deletion mapping panel divided the short arm into five distinct subregions (A-E). The 3p fragments were distributed on 3p regions as follows: region A, 26%; B, 31%; C, 4%; D, 4% and E, 35%. We screened 300 single-copy DNA fragments from the distal part of 3p (regions A and B) with ten restriction endonucleases for their ability to detect restriction fragment length polymorphisms (RFLPs). Of these fragments 110 (36%) were found to detect useful RFLPs: 35% detected polymorphisms with frequency of heterozygosity of 40% or higher, and 25% with frequency of 30% or higher. All polymorphisms originated from single loci and most of them were of the base pair substitution type. These RFLP markers make it possible to construct a fine linkage map that will span the distal part of chromosome 3p and encompasses the von Hippel-Lindau disease locus. The large number of single-copy fragments (2,000) spaced every 100–150 kb on chromosome 3 will make a significant contribution to mapping and sequencing the entire chromosome 3. The 300 conserved chromosome 3 probes will increase the existing knowledge of man-mouse homologies. 相似文献
99.
Shin'ichi Saito Tamotsu Inoue Ichiro Kawase Hideki Hara Yoshiro Tanio Isao Tachibana Seiji Hayashi Masatoshi Watanabe Machiko Matsunashi Tadashi Osaki Tomiya Masuno Susumu Kishimoto 《Cancer immunology, immunotherapy : CII》1991,33(3):165-170
Summary Murine IgG1 monoclonal antibodies (mAbs), ITK-2 and ITK-3, were generated against a small-cell lung cancer (SCLC) cell line. Enzyme-linked immunosorbent assay using a variety of established cell lines as substrates, immunoperoxidase staining of freshly frozen tissue sections, and fluorescence-activated cell sorter analysis of peripheral blood leukocytes showed that these mAbs recognize a part of the SCLC-associated cluster 1 antigen. In immunoprecipitation studies, both ITK-2 and ITK-3 bound to a 145-kDa glycoprotein of SCLC cell membrane extracts, as did MOC-1 and NKH-1, which both recognize the cluster 1 antigen. However, because the binding of125I-labeled ITK-2 to SCLC cells was not inhibited by MOC-1 or NKH-1, the binding site of ITK-2 on SCLC cells appeared to be different from that of either MOC-1 or NKH-1. Unexpectedly, binding of125I-labeled ITK-2 to SCLC cells increased in the presence of ITK-3. This ITK-3-induced increase in ITK-2 binding was due partly to an increase in the number of binding sites for ITK-2 on SCLC cells. Addition of ITK-3 may, therefore, improve the effectiveness of ITK-2-based tumor detection or therapy. 相似文献
100.
Dr. Tomonobu Kusano Kazuyuki Sugawara Chihiro Inoue Nobuhiro Suzuki 《Current microbiology》1991,22(1):35-41
The genes coding ford-ribulose-1,5-bisphosphate carboxylase (RuBPCase) from an iron-oxidizing bacterium,Thiobacillus ferrooxidans, were cloned into anEscherichia coli plasmid, pUC18. The recombinant plasmid, termed pTR11, contained a 4.0-kb PstI fragment including the entire coding regions for both large and small subunits of RuBPCase.Escherichia coli carrying pTR11 did not show any CO2-fixing activity. However, a derivative plasmid with an appropriate deletion, which was placed under the control of atac promoter, conferred ribulose bisphosphate-dependent CO2-fixing activity on the host cell. Analysis of gel-filtration chromatography of the RuBPCase synthesized inE. coli revealed that it had a hexadecameric form like the native enzyme ofT. ferrooxidans. 相似文献