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21.
22.
Tadao Niijima Takashi Umeda Manabu Kuriyama Hiroyuki Ohmori Yohsuke Matsumura Tomoyasu Tsushima Toyoko Tanahashi Jun Yoshimoto Toshihiko Asahi Norimasa Ike Taiichiro Johsen Noritaka Ishido Naoki Mitsuhata Takeshi Uyama Hiroyoshi Tanaka Hideo Ueda Jisaburo Sakatoku Norio Yamamoto Kazuo Nagata Yukitoshi Fujita Masaaki Morioka Kazuo Kurokawa Susumu Kagawa Tomoyuki Ishibe Yasutoshi Himeno Toyofumi Ueda 《Cancer immunology, immunotherapy : CII》1989,30(2):81-85
Summary In order to examine its clinical efficacy, recombinant human interferon- (rIFN-) was instilled intravesically into 51 patients with superficial bladder cancer. Ten patients, who received intermittent intravesical instillation at a dose of (3–36) × 106 U rIFN- on days 1–3 every week, showed no response. Thirty-two patients received intravesical instillation at a dose of (3–36) × 106 U every day for 10–20 days. Eight patients showed partial response, indicating an efficacy rate of 25%. Nine patients received divided doses of 18 × 106 U twice a day every day for 10–20 days. Six patients showed partial response, indicating an efficacy rate of 67%. This value was significantly higher than that obtained by administering divided doses. The response to intravesical instillation therapy with rIFN- varies with treatment protocol. Frequent and longer exposure to rIFN- may induce better regression of superficial bladder cancer. Six incidences of side-effects were found in five cases (9.8%): pollakiuria in one, pain on micturition in two, fever in two, and eruption in one case. All of these side-effects were slight and reversible after drug withdrawal. Laboratory tests showed only a few changes with low severity. Thus, rIFN- is potentially a new drug for instillation therapy of superficial bladder cancer, in view of the absence of adverse effects. 相似文献
23.
M Hirata Y Watanabe T Ishimatsu T Ikebe Y Kimura K Yamaguchi S Ozaki T Koga 《The Journal of biological chemistry》1989,264(34):20303-20308
A series of inositol 1,4,5-trisphosphate (IP3) analogs and positional isomers was examined to explore the structure-activity relationships among IP3 5-phosphatase, IP3 3-kinase, and the release of Ca2+. All analogs with additional groups on the 2nd position of IP3 inhibited the hydrolysis of [5-32P]IP3 catalyzed by erythrocyte ghosts, with a lower Ki value than seen with IP3. IP3 dehydroxylated at the 2nd position also had a lower Ki, while 2,4,5-IP3 or cyclic(1:2), 4,5-IP3 had higher Ki values. Among these compounds 2-deoxy-IP3 was as potent as IP3 in inhibiting the phosphorylation by [3H] IP3-3-kinase in rat brain cytosol. The other compounds, except for 2,4,5-IP3 inhibited the phosphorylation, however, 2-30 times higher concentrations were required. By lowering free Ca2+, the concentrations required for half-maximal inhibition were low, while those of IP3, 2-deoxy-IP3, and positional isomers remained unchanged. These compounds acted as full agonists in releasing Ca2+ from permeabilized macrophages, although 1.6-50-fold higher concentrations than IP3 were required. These compounds also inhibited the binding of [3H]IP3 to rat cerebellum and bovine adrenal cortex microsomes, but the potencies were 2.9-33 times less than that of IP3. Thus, the 2nd position of IP3 can be modified with only a slight loss of biological activity. 相似文献
24.
Two variants of carrot (Daucus carota L. cv. MS Yonsun) celllines, which had been selected with Al-phosphate as a sole sourceof phosphorous, were characterized on their mechanisms of phosphate-utilizationfrom Al-phosphate. Both cell lines excreted citrate into themedium. The amount of citrate excretion was highly correlatedwith cell growth in the presence of Al-phosphate. There wasabout a 1 to 1 correlation between solublized-Al and excreted-citratein the medium during cell growth. These results suggest that1) the citrate could chelate with Al, at a 1 to 1 ratio, inAl-phosphate, 2) the citrate-chelated Al remains outside thecells, and 3) solublized phosphate from Al-phosphate is utilizedfor the growth of carrot cells. The characteristics of the selectedcells were very stable, since the rate of citrate-excretionshowed no change after subculturing 25 passages without Al-phosphate. (Received August 7, 1989; Accepted October 19, 1989) 相似文献
25.
Using microparticle labeling and counting for attomole-level detection in heterogeneous immunoassay.
A new heterogeneous "sandwich" immunoassay utilizing microparticles as labels to realize high sensitivity is described. In this method, antibody fixed on the microparticles reacts with antigen previously trapped on a microplate surface, which makes the antigen molecules visible and countable with an inverted optical microscope. The method is highly sensitive because the reacted single microparticle, therefore single antigen molecule, can be detected. The sensitivity depends both on the reaction efficiency of the immunoreaction and on nonspecific adsorption of the microparticles on the microplate surface. Therefore, the protocol for preparing microparticle having antibody on the surface and a microplate having capture antibody was investigated to realize high sensitivity. Carboxylated microparticles of 0.76 microns in diameter were conjugated with affinity-purified antibody using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide. It was determined that 1 g microparticles had 880 micrograms antibody (approximately 1100 antibody molecules per 1 microparticle). The immunoreaction efficiency reached 18% at 1 x 10(-13) mol/liter antigen concentration. The lower detection limit was 3.1 x 10(-14) mol/liter (1.6 amol) using human alpha-fetoprotein as a model antigen. 相似文献
26.
Gene expression and immunohistochemical localization of basic fibroblast growth factor in renal cell carcinoma. 总被引:2,自引:0,他引:2
J Eguchi K Nomata S Kanda T Igawa M Taide S Koga F Matsuya H Kanetake Y Saito 《Biochemical and biophysical research communications》1992,183(3):937-944
Renal cell carcinoma is known as a neoplastic condition of renal tubular cells and usually shows a hypervascular tumor in angiographic examination. We examined the presence of basic fibroblast growth factor (bFGF) in human renal cell carcinoma. To determine if alterations in bFGF gene expression are present in human renal cell carcinoma, paired samples of normal and neoplastic renal tissue from 6 patients were analyzed for bFGF mRNA content by Northern blot hybridization. In 4 out of 6 patients, tumor tissue expressed bFGF mRNA 2 to 4 times greater than corresponding normal tissue. Two patients showed minimal elevation of tumor bFGF mRNA. The localization of bFGF in the renal cell carcinoma tissue was also examined using immunohistochemical staining, and it was found that bFGF was positively stained at the nuclei of tumor cells and the cell surface. These results suggest that increased expression of bFGF may be associated with neoplastic growth in renal tubular epithelial cells and neovascularization. 相似文献
27.
Hiroko Soda Shigenori Yukizane Ichiro Yoshida Yasutoshi Koga Shuichi Aramaki Hirohisa Kato 《Human genetics》1996,97(4):435-437
We have analyzed two unrelated Japanese patients with carbonic anhydrase II deficiency born to consanguineous parents. We
have identified the same mutation as that reported to be homozygous in a Belgian family and compound heterozygous in an American
family. It comprises to C-to-T transition that results in the amino acid substitution of Tyr (TAT) for His (CAT) at position
107. This point mutation creates an AccI site that can be conveniently screened by the polymerase chain reaction/restriction fragment length polymorphism method
using a restriction enzyme for gene tracking. Our patients exhibit severe mental retardation, not seen in the Belgian and
American patients.
Received: 23 November 1994 / Revised: 22 May 1995 相似文献
28.
Minamisawa Kiwamu; Ogawa Ken-Ichiro; Fukuhara Hideyuki; Koga Jinichiro 《Plant & cell physiology》1996,37(4):449-453
Indole-3-acetaldehyde (IAAId) was detected in the culture supernatantof Bradyrhizobium elkanii. Deuteriumlabelled L-tryptophan (Trp)was incorporated into IAAId and indole-3-acetic acid (IAA),suggesting that B. elkanii produces IAA via IAAId from Trp.In B. elkanii cell suspension, indole-3-pyruvic acid (IPyA)was converted to IAAId, and exogenously added IAAId was rapidlyconverted to IAA. Furthermore, the activity of indolepyruvatedecarboxylase (IPDC), which catalyzes the decarboxylation ofIPyA to produce IAAId and is a key enzyme for IPyA pathway,was detected in B. elkanii cell-free extract. The IPDC activitydepended on Mg2+ and thiamine pyrophosphate, cofactors of decarboxylation.This mounting evidence strongly suggests that IAA synthesisoccurs via IPyA pathway (Trp IPyA p IAAId IAA) in B. elkanii. (Received December 11, 1995; Accepted March 4, 1996) 相似文献
29.
Furukawa Toshiko; Koga Jinichiro; Adachi Takashi; Kishi Kunihei; Syono Kunihiko 《Plant & cell physiology》1996,37(7):899-905
In a study of various phytopathogenic fungi, we found that fungithat belong to the genus Rhizoctonia produce IAA efficientlyfrom tryptophan. R. solani Kühn MAFF-305219, in particular,produced large amounts of tryptophol (Tol), which was assumedto be a specific by-product of the indole-3-pyruvate (IPy) pathway,in addition to IAA. Therefore, this fungus seemed suitable foranalysis of the function and the regulation of the biosynthesisof auxin by a fungal pathogen. Under normal aerobic conditions,the ratio of IAA to Tol synthesized by this strain was higherthan that under less aerobic conditions. In metabolic studieswith various indole derivatives, R. solani converted L-tryptophanand indole-3-acetaldehyde to IAA and Tol, but other indole derivativeswere scarcely metabolized. These results suggest that both IAAand Tol are synthesized from tryptophan through the IPy pathwayin Rhizoctonia. (Received May 27, 1996; Accepted July 8, 1996) 相似文献
30.
Expression of NADH-Dependent Glutamate Synthase in Response to the Supply of Nitrogen in Rice Cells in Suspension Culture 总被引:2,自引:0,他引:2
Watanabe Sachiko; Sakai Takahiro; Goto Satoshi; Yaginuma Toshiko; Hayakawa Toshihiko; Yamaya Tomoyuki 《Plant & cell physiology》1996,37(7):1034-1037
The effects of inorganic and organic nitrogen on the levelsof mRNA for NADH-dependent glutamate synthase (GOGAT) and theprotein were examined in rice cells in suspension culture. Asupply of NH+4, NO-3, glutamine, or asparagine induced the accumulationof the protein and mRNA, but levels of mRNA for ferredoxin-GOGATwere hardly affected.
1Present address: P.C. Center Wakuya-cho, Toda-gun, Miyagi,Japan. 相似文献