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21.
Establishment and characterization of a human chorionic gonadotropin (hCG) producing cell line (RTSG) from an ovarian epithelial cancer 总被引:3,自引:0,他引:3
Y Udagawa S Nozawa K Chin M Sakayori M Mikami K Ohta K Tsukazaki K Kiguchi R Iizuka 《Human cell》1990,3(1):70-75
A new cell line designated RTSG established in vitro from the pleural effusion of a patient with metastatic ovarian epithelial cancer has been subcultured 46 times for more than 2 years. The cells grew in a monolayered sheet, showing a tendency to pile up, with the population doubling in 48 hrs. Electron-microscopically, desmosomes were characteristically observed, suggesting the cells were of epithelial origin. Chromosomal analysis revealed aneuploidy with a tetraploid mode. The heterotransplanted tumors in nude mice were histopathologically classified as a poorly differentiated adenocarcinoma, whereas the original tumor consisted mainly of mucinous and serous cystadenocarcinoma and only partly of poorly differentiated adenocarcinoma. The cells secreted hCG (38.8 mIU/day/10(6) cells) and beta-hCG (6.1 ng/day/10(6) cells) in spent medium. Immunocytologic +-and-histochemical staining for tumor markers of the original tumor, the cultured cells and the transplanted tumors also revealed the localization of not only hCG and beta-hCG but also CA19-9 and CA-125 whose values had been elevated in the preoperative serum (hCG: 10 mIU/ml, CA19-9: 6,400 U/ml, CA-125: 225 U/ml). Results of PAS, Alcian-blue and Mucicarmine strains indicated that most of the PAS-positive substances in the cultured cells and the transplanted tumors were consistent with glycogen while the original tumor mainly contained mucin except for the lesion of poorly differentiated adenocarcinoma with glycogen. These results suggested that the cultured cells might originate from poorly differentiated adenocarcinoma cells in the original tumor. 相似文献
22.
K. K. Mäkinen C.-Y. Chen P.-L. Mäkinen K. Ohta W. J. Loesche 《Molecular microbiology》1990,4(8):1413-1417
The benzoylarginine peptidase of Treponema denticola (strain ASLM; a human oral spirochaete) was progressively and irreversibly inactivated by 1-(ethoxycarbonyl)-2-ethoxy-1, 2-dihydroquinoline, a carboxyl-group reagent. At acidic pH values, reaction of one mole of the modifier per active site of the enzyme resulted in total inactivation of the enzyme. Assuming that this modifier is a specific carboxyl reagent, the data suggest that the inactivation of the T. denticola benzoylarginine peptidase was caused by the modification of one carboxyl group located close to the active site of the enzyme. Results obtained with Woodward's reagent K (N-ethyl-5-phenylisoxazolium 3'-sulphonate) supported these findings. Carbethoxylation with diethylpyrocarbonate effectively inactivated the enzyme, and addition of hydroxylamine at pH 7.0 restored the activity almost totally, suggesting that the pyrocarbonate had reacted with tyrosyl or histidyl residues. 相似文献
23.
Oka Kotaro; Ikeshima Hiroko; Ishikawa Hideo; Ohta Eiji; Sakata Makoto 《Plant & cell physiology》1988,29(5):771-775
We showed that the surface charge density of protoplasts canbe estimated by the 9-aminoacridine method. The estimated surfacecharge density of the protoplasts isolated from elongating regionsof Vigna mungo root was 39 ? 8 mC/m2. The negative surfacecharge density increased when protoplasts were treated withglutaraldehyde or when EDTA was added to the protoplast suspensionmedium. These results support the validity of our estimationof the surface charge density of protoplasts by the 9-aminoacridinemethod. The concentration of amino groups at the surface ofthe protoplasts was estimated to be 34 mC/m2. (Received June 19, 1987; Accepted April 11, 1988) 相似文献
24.
Isogai Akira; Takayama Seiji; Shiozawa Hideyuki; Tsukamoto Chise; Kanbara Takeshi; Hinata Kokichi; Okazaki Keiichi; Suzuki Akinori 《Plant & cell physiology》1988,29(8):1331-1336
S-Glycoproteins (S-locus-specific glycoproteins) in Brassicaspecies are present only in stigmas and thought to play an importantrole in self-incompatibility system. The stigma extract containsalso several other glycoproteins reacting with the antiserumto S-glycoproteins, among which some glycoproteins from S8S8-and S9S9-homozygotes have the same pI value. Both of the glycoproteinswhich were tentatively termed NS8- and NS8S9-glycoproteins,respectively, were isolated and analyzed. Those were revealedto be identical. Its amino acid sequence was homologous withthe S-glycoproteins in Brassica species. The NS-glycoproteinswere expressed at the same time and only in stigma as S-glycoproteins. (Received July 19, 1988; Accepted September 7, 1988) 相似文献
25.
Yazaki Yoshiaki; Maki Kazutoshi; Sato Tetsuya; Ohta Eiji; Sakata Makoto 《Plant & cell physiology》1988,29(8):1417-1422
The intracellular K+ concentration and its change in mung bean[Vigna mungo (L.) Hepper] root tips were investigated non-invasivelywith 39K nuclear magnetic resonance spectroscopy using a membraneimpermeable shift reagent, dysprosium (III) tripolyphosphate[Dy(PPPi)72]. The K+ resonance was shifted to highermagnetic field in proportion to the concentration of the shiftreagent. In addition to a reference capillary peak for measuringthe K+ concentration, two well-resolved peaks (intra- and extracellularK+ resonances) were observed in the 39K NMR spectra of mungbean root tips. The intracellular K+ concentration was determinedto be 41 mM, which was similar to the value obtained by flamephotometry. When 20 mM KCl was added to the external medium,the intensity of the intracellular K+ resonance gradually increasedand the net K+ uptake rate was calculated to be 4.1 micromolesper gram fresh weight per hour. After removal of KCl from theperfusion medium, the intracellular K+ concentration considerablydecreased. With 31P NMR method, 2.5 mM Dy(PPPj)712 and20 mM KCl had little effect on the ATP level in the cells. Wehave indicated that the 39K NMR method can be used to determinethe K+ levels and net fluxes of the K+ transport in perfusedroot tips successively. (Received April 6, 1988; Accepted September 29, 1988) 相似文献
26.
Complete nucleotide sequence of the mitochondrial DNA from a liverwort,Marchantia polymorpha 总被引:1,自引:1,他引:0
Kenji Oda Katsuyuki Yamato Eiji Ohta Yasukazu Nakamura Miho Takemura Naoko Nozato Kinya Akashi Takeshi Kanegae Yutaka Ogura Takayuki Kohchi Kanji Ohyama 《Plant Molecular Biology Reporter》1992,10(2):105-163
Libraries of cosmid and plasmid clones covering the entire region of mtDNA from the liverwortMarchantia polymorpha were constructed. These clones were used for the determination of the complete nucleotide sequence of the liverwort mtDNA
totally 186,608 bp (GenBank no. M68929) and including genes for 3 species of ribosomal RNAs, 29 genes for 27 species of transfer
RNAs, and 30 genes for functionally known proteins (16 ribosomal proteins, 3 subunits of cytochromec oxidase, apocytochromeb protein, 3 subunits of H+-ATPase, and 7 subunits of NADH ubiquinone oxidoreductase). The genome also contains 32 unidentified open reading frames.
Thus the complete nucleotide sequences from both chloroplast and mitochondrial genomes have been determined in the same organism.
Plasmid clones are available upon the request.
Gene names are represented according to Lonsdale and Leaver (1988) with modifications recommended by Lonsdale (personal communication). 相似文献
27.
Ligand-sensitive binding of actin-binding protein to immunoglobulin G Fc receptor I (Fc gamma RI). 总被引:7,自引:0,他引:7
The high affinity receptor that binds the Fc domain of immunoglobulin G (IgG) subclasses 1 and 3 (Fc gamma RI) mediates important immune defense functions by inducing cell surface changes on human leukocytes. In this article, we document direct high affinity binding of Fc gamma RI to the actin filament cross-linking protein, actin-binding protein (ABP). In the absence of IgG, all Fc gamma RI molecules in undifferentiated cells of myeloid line U937 bound to ABP over a 9-fold range of Fc gamma RI expression induced by human IFN-gamma. Binding of IgG to U937 cells constitutively expressing Fc gamma RI or to COS cells genetically transfected to express Fc gamma RI rapidly decreased the avidity of Fc gamma RI for ABP. This finding suggests the existence of a pathway communicating a signal between a functional IgG receptor and intracellular components involved in the effector responses to Fc gamma RI-ligand interaction. 相似文献
28.
M Ohta K Ohta H Hara N Itoh Y Itagaki H Nishitani K Hayashi 《Biochemistry international》1991,25(6):1087-1093
We synthesized a peptide designated R8 (amino acid residues 1157-1201) based on the primary structure presumed from the nucleotide sequence of the cDNA clone from the gene for Duchenne muscular dystrophy. Antibody to the synthetic R8 generated by immunization of rabbits was tested on human and mouse skeletal muscle by Western blotting analysis. The antibody reacted with a component of the 400K dystrophin of normal human and mouse skeletal muscles, but not with components of the muscles of Duchenne muscular dystrophy patients and mdx mice. Thus we established that this peptide sequence is in fact missing in the protein product 'dystrophin' encoded by the DMD gene. The antibody may prove useful for the diagnosis of the Duchenne types of muscular dystrophy. 相似文献
29.
Masahiko Sakaguchi Kazumitsu Hanai Kunimasa Ohta Masaaki Kitajima Sachiko Matsuhashi Katsuji Hori Hiromichi Morita 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,168(4):409-416
Summary Reduced glutathione evokes a feeding response, the tentacle-ball formation inHydra japonica. This response consists of at least 5 components (R1–R5). We raised 6 monoclonal antibodies (mAbs), each of which depressed a specific subset of these components, and we also examined the immunocytochemical localization of antigens with these mAbs at light microscopic level. The 2 mAbs that depressed R2 and R4 bound to the cnidocils of the desmoneme and the stenotele nematocytes; the 3 mAbs that depressed R5 bound to the apical surface adjacent to the cnidocils of the nematocytes; and the 2 mAbs that depressed R1 and R3 bound to the apical spot structures of unidentified cells in the ectoderm.Together with the specificity of the action of the mAbs on the behavioral response, the correspondence between the effects on the response and the structures visualized with these mAbs suggests that these structures include components of the receptor-effector system relevant to chemoreception. 相似文献
30.
Aqualysin I is an alkaline serine protease which is secreted into the culture medium by Thermus aquaticus YT-1, an extreme thermophile [Matsuzawa, H., Hamaoki, M. & Ohta, T. (1983) Agric. Biol. Chem. 47, 25-28]. The gene encoding aqualysin I was cloned into Escherichia coli using synthetic oligodeoxyribonucleotides as hybridization probes. The nucleotide sequence of the cloned DNA was determined. The primary structure of aqualysin I, deduced from the nucleotide sequence, agreed with the NH2-terminal sequence previously reported and the determined amino acid sequences, including the COOH-terminal sequence, of the tryptic peptides derived from aqualysin I. Aqualysin I comprised 281 amino acid residues and its molecular mass was determined to be 28,350. On alignment of the whole amino acid sequence, aqualysin I showed high sequence homology with the subtilisin-type serine proteases, and 43% identity with proteinase K, 37-39% with subtilisins and 34% with thermitase. Extremely high sequence identity was observed in the regions containing the active-site residues, corresponding to Asp32, His64 and Ser221 of subtilisin BPN'. The nucleotide sequence of the cloned DNA (1105 nucleotides) revealed that it contains the entire gene encoding aqualysin I and one open reading frame without a translational stop codon. Therefore, aqualysin I was considered to be produced as a large precursor, which contains a NH2-terminal portion, the protease and a COOH-terminal portion. The G + C content of the coding region for aqualysin I was 64.6%, which is lower than those of other Thermus genes (68-74%). The codon usage in the aqualysin I gene was rather random in comparison with that in other Thermus genes. 相似文献