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61.
Katsuyuki Haranaka Nobuko Satomi Akiko Sakurai Ruriko Haranaka Naoko Okada Mosaburo Kobayashi 《Cancer immunology, immunotherapy : CII》1985,20(1):1-5
Summary The antitumor activities and capacity for tumor necrosis factor (TNF) production of traditional Chinese herbal preparations (Zhu-ling-tang, Xiao-chai-hu-tang), crude drugs (Polyporus, Hoelen, Bupleuri radix, Angelica radix, Cnidii rhizoma, Cinnamomum cortex), and Krestin (PSK) were investigated. These drugs were given to DDY mice in the drinking water before and after transplantation of Ehrlich tumors, and the development of the intradermally transplanted Ehrlich tumors and survival rate were observed. A good survival rate and sometimes a complete cure were found in the groups administered Bupleuri radix, Xiao-chai-hu-tang, Angelica radix, or Cinnamomum cortex, while the group given Hoelen showed poor results. To examine the capacity for TNF production these drugs were given to DDY mice PO as initial stimulating agents, to stimulate the reticuloendothelial system (RES) prior to lipopolysaccharide injection. The TNF activity was tested from the cytotoxicity against L cells. Significant differences in capacity for TNF production were observed among the drugs. Relatively high levels of TNF activity were noted in the groups given Angelica radix, Bupleuri radix, Cnidii rhizoma, or Cinnamomum cortex, very low activities in the groups given Xiao-chai-hu-tang, Zhu-ling-tang, or Krestin, and no TNF activities in the groups given Polyporus or Hoelen. The TNF capacity for production broadly paralleled the survival rate of the mice transplanted to Ehrlich tumors. Our findings suggest that one mechanism underlying the antitumor activities of these drugs is based on stimulation of the RES and is closely related of TNF production.This work was supported in part by a grant-in-aid from the Ministry of Education, Japan 相似文献
62.
DNA-DNA hybridization analysis of nylon oligomer-degradative plasmid pOAD2: identification of the DNA region analogous to the nylon oligomer degradation gene. 总被引:4,自引:3,他引:1 下载免费PDF全文
Fine structure of the gene of 6-aminohexanoic acid cyclic dimer hydrolase, one of the enzymes responsible for the degradation of the nylon oligomer (6-aminohexanoic acid cyclic dimer), on the plasmid pOAD2 harbored in Flavobacterium sp. KI72 was determined by constructing miniplasmids from plasmid pNDH5 (a hybrid plasmid consisting of pBR322 and a 9.1-kilobase-pair HindIII fragment of pOAD2 ). The 6-aminohexanoic acid cyclic dimer hydrolase produced by cells of Escherichia coli C600 harboring pNDH5 or its miniplasmid was examined immunologically and electrophoretically and was found to be identical to that of Flavobacterium sp. KI72 . A fragment of pOAD2 (17.2- to 19.1-kilobase-pair region on pOAD2 ) was detected as hybridized fragment by Southern blotting experiments, indicating the presence of the DNA region analogous to the 6-aminohexanoic acid cyclic dimer hydrolase gene on the plasmid. 相似文献
63.
Production of transgenic fish: introduction and expression of chicken delta-crystallin gene in medaka embryos 总被引:3,自引:0,他引:3
K Ozato H Kondoh H Inohara T Iwamatsu Y Wakamatsu T S Okada 《Cell differentiation》1986,19(4):237-244
To produce a model of transgenic fish, recombinant plasmids containing chicken delta-crystallin gene were microinjected into the oocyte nucleus of a small teleost, medaka (Oryzias latipes). About 50% of the microinjected oocytes developed to 7-day-old embryos. By Southern blotting delta-crystallin gene was detected in 4 of 8 embryos, and, by Western blotting, delta-crystallin polypeptides in 5 of 16. In 1 of 6 examined histologically, delta-crystallin DNA was detected in all the tissues, and delta-crystallin polypeptides, in many of the tissues including the lens. Thus, the exogenous gene and/or its products were detected in 10 of 30 embryos examined. This is the first report of successful production of transgenic fish. 相似文献
64.
Summary Normal skeletal and cardiac striated muscle from adult rats was incubated for the cytochemical detection of acid phosphatase activity with cerium as the capture metal. Results from these experiments show that normal striated muscle has a greater number of acid phosphatase-positive structures, which are presumed to be lysosomes, than has been indicated by several previous cytochemical studies.Supported in part by grants AI 17945 and HL 17747 from the United States Public Health Service, National Institutes of Health 相似文献
65.
IMP dehydrogenase. II. Purification and properties of the enzyme from Yoshida sarcoma ascites tumor cells 总被引:1,自引:0,他引:1
The preceding paper showed that IMP dehydrogenase [IMP:NAD+ oxidoreductase, EC 1.2.1.14] tended to form a precipitable complex(es) through ionic and hydrophobic interactions. On the basis of these observations, a method was developed for purification of IMP dehydrogenase from Yoshida sarcoma ascites cells. On SDS-polyacrylamide gel electrophoresis, the purified preparation (1.19 U/mg protein) appeared homogeneous and its minimum molecular weight was estimated to be 68K daltons. Amino acid analyses indicated a subunit molecular weight of 68,042. Molecular sieve chromatography in the presence of 10% (NH4)2SO4 showed that the molecular weight of the native enzyme was 127K daltons. These values indicate that the native enzyme is composed of two identical subunits. However, the purified enzyme gave 4 protein bands on polyacrylamide gel electrophoresis under non-denaturing conditions, and appeared as a single fraction in the vicinity of the void volume on Ultrogel AcA 34 column chromatography at low salt concentration, indicating that its molecular weight exceeded 200K daltons. These findings indicate that the enzyme tends to aggregate owing to its own physicochemical characteristics. The Km values for IMP and NAD were calculated to be 12 and 25 microM, respectively, and the Ki values for XMP, GMP, and AMP to be 109, 130, and 854 microM, respectively. The purified enzyme showed full activity in the presence of K+, and K+ could be partially replaced by Na+. PCMB inactivated the enzyme, but the activity was completely restored by the addition of DTT. Cl-IMP also inactivated the enzyme and IMP prevented this inactivation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
66.
A biosensor consisting of immobilized nitrite oxidizing bacteria and an oxygen electrode has been developed for the amperometric determination of NO(2) (nitrogen dioxide) gas. The response time for the determination of NO(2) was within 3 min. A linear relationship was observed between the current decrease and the NO(2) concentration below 255 ppm. The minimum concentration for the determination of NO(2) was 0.51 ppm. The current decrease was reproducible within +/-4% of the relative error. The selectivity of the microbial sensor for NO(2) was satisfactory. The current output of the sensor was almost constant for more than 24 days and 400 assays. 相似文献
67.
68.
Mutations induced by repeated EMS treatments were investigated by using mouse L5178Y cells. The frequency of TGr mutations increased linearly with the number of EMS treatments whereas the yield of BrdUrdr mutations showed a curvilinear dose-response curve. The BrdUrdr frequency was roughly proportional to the square of the TGr frequency and the results were compatible with the hypothesis that BrdUrdr cells were induced by two mutational events within a cell. Most of the BrdUrdr colonies isolated after 6 EMS treatments, however, were unstable. When BrdUrdr colonies that had arisen in BrdUrd medium after 2 weeks' incubation were isolated in normal medium, the descendant cells showed a nearly normal level of thymidine incorporation and low plating efficiencies of about 1% in BrdUrd medium. In contrast, after isolation of the same colonies in BrdUrd medium, a low level of thymidine incorporation and high plating efficiencies in BrdUrd medium were observed in the descendant cells.
Reverse selection from BrdUrdr to HATr was accomplished with frequencies of 10−6−10−3 for the descendants grown in BrdUrd medium, and AzaCyd treatment drastically increased the reversion frequency to nearly 10−1. Further re-revertants from HATr to BrdUrdr were also found with frequencies of 10−3−10−2 without treatment. These results indicate that the initial BrdUrdr cells did not result from inactivation of the thymidine-kinase gene but that the mode of gene expression was altered in some way. 相似文献
69.
Masaji Koshioka Alan Jones Mayumi N. Koshioka Richard P. Pharis 《Phytochemistry》1983,22(7):1585-1590
The native gibberellin A4 (GA4), in radioactive form ([1,2-3H]GA4, 1.06 Ci/mmol), was fed to carrot somatic cell cultures (suspension and immobilized cell systems) and its metabolism over a 48 hr period was investigated. It was found that the [3H]GA4 was metabolized to at least two GAs, [3H]GA1 and [3H]GA8, six GA glucosyl conjugates, [3H]GA1-0(3)-glucoside, [3H]GA1-0(13)-glucoside, [3H]GA1-glucosyl ester, [3H]GA4-glucoside, [3H]GA4-glucosyl ester, a [3H]GA8 glucosyl conjugate(s) and a previously unknown [3H]GA1 glucosyl conjugate ([3H]GA1-0(3,13)-diglucoside-like compound). The GA1-diglucoside-like compound was found only in extracts of cells and was present in significant amounts (33 % of total extractable radioactivity). All other metabolites were present in both cells and medium. For extracts of the medium, no differences between the suspension and immobilized cultures existed in types of [3H]GA4 metabolites although quantitative differences were apparent. 相似文献
70.
The effect of Cr(III) administration on hepatic RNA synthesis in mice was studied. It was found that Cr accumulated in mouse liver. Forty-eight hours after intraperitoneal injection of CrCl3 (0.005-5 mg Cr/kg body weight) approximately 10% of the administered dose per g of tissue remained. The accumulated Cr was still retained 64 days after administration (5 mg Cr/kg) with only a slight decrease. Approximately 20% of the hepatic Cr was detected in the nuclei. By administering CrCl3. RNA synthesis in mouse liver was markedly enhanced without altering the pool size of nucleotides. This enhancement was dose-dependent and statistically significant at doses of 0.05 (p less than 0.05), 0.5 (p less than 0.01), and 5 mg Cr/kg (p less than 0.01), and remained so for at least 16 days after administration of 5 mg Cr/kg. The synthesis of DNA and protein in mouse liver were not significantly changed by CrCl3 administration. On the other hand, Cr(VI) administration did not enhance but rather inhibited RNA synthesis in mouse liver. These results suggest that Cr(III) specifically enhances RNA synthesis in mouse liver. 相似文献