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1.
Masaru Kubota Ying-Wei Lin Keigo Hamahata Machiko Sawada Seiji Koishi Haruyo Hirota Yoshihiro Wakazono 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2000,470(2):21
The occurrence of a second neoplasm is one of the major obstacles in cancer chemotherapy. The elucidation of the genotoxic effects induced by anti-cancer drugs is considered to be helpful in identifying the degree of cancer risk. Numerous investigations on cancer patients after chemotherapy have demonstrated: (i) an increase in the in vivo somatic cell mutant frequency (Mf) at three genetic loci, including hypoxanthine–guanine phosphoribosyl-transferase (hprt), glycophorin A (GPA), and the T-cell receptor (TCR), and (ii) alterations in the mutational spectra of hprt mutants. However, the time required for and the degree of such changes are quite variable among patients even if they have received the same chemotherapy, suggesting the existence of underlying genetic factor(s). Accordingly, some cancer patients prior to chemotherapy as well as patients with cancer-prone syndrome have been found to show an elevated Mf. Based on the information obtained from somatic cell mutation assays, an individualized chemotherapy should be considered in order to minimize the risk of a second neoplasm. 相似文献
2.
Phagocytosis of microspheres in V79 Chinese hamster lung cells was investigated by flow cytometry. Fluorescent microspheres (1.8 micron diameter) were used as the ingesta. Change in the number of V79 cells containing fluorescent microspheres was measured as an index of phagocytic activity. With time there was a sigmoidal increase in cells containing microspheres. The phagocytosis of microspheres is partially explained by two parameters introduced to describe the sigmoidal curves. 相似文献
3.
4.
Saki Itonori Kazuya Hidari Yutaka Sanai Masaru Taniguchi Yoshitaka Nagai 《Glycoconjugate journal》1989,6(4):551-560
The effect of the chain length of the fatty acid residue of the ceramide moiety of ganglioside GM3 on the binding ability of monoclonal antibody M2590, which is specific for the carbohydrate structure of GM3-ganglioside, was examined by means of a direct binding assay on thin layer chromatography plates (TLC immunostaining) and a quantitative enzyme-linked immunosorbent assay (ELISA). Derivatives of GM3 with a long fatty acid chain reacted with the M2590 antibody, but those with a short fatty acid chain showed no reaction in either assay system. These results suggested that the acyl fatty acid moiety of the ganglioside played an important role in the formation or maintenance of the antigenic structure of the carbohydrate moiety of the ganglioside. 相似文献
5.
Regeneration of bovine and octopus opsins in situ with natural and artificial retinals 总被引:4,自引:0,他引:4
Y Koutalos T G Ebrey M Tsuda K Odashima T Lien M H Park N Shimizu F Derguini K Nakanishi H R Gilson 《Biochemistry》1989,28(6):2732-2739
We consider the problem of color regulation in visual pigments for both bovine rhodopsin (lambda max = 500 nm) and octopus rhodopsin (lambda max = 475 nm). Both pigments have 11-cis-retinal (lambda max = 379 nm, in ethanol) as their chromophore. These rhodopsins were bleached in their native membranes, and the opsins were regenerated with natural and artificial chromophores. Both bovine and octopus opsins were regenerated with the 9-cis- and 11-cis-retinal isomers, but the octopus opsin was additionally regenerated with the 13-cis and all-trans isomers. Titration of the octopus opsin with 11-cis-retinal gave an extinction coefficient for octopus rhodopsin of 27,000 +/- 3000 M-1 cm-1 at 475 nm. The absorption maxima of bovine artificial pigments formed by regenerating opsin with the 11-cis dihydro series of chromophores support a color regulation model for bovine rhodopsin in which the chromophore-binding site of the protein has two negative charges: one directly hydrogen bonded to the Schiff base nitrogen and another near carbon-13. Formation of octopus artificial pigments with both all-trans and 11-cis dihydro chromophores leads to a similar model for octopus rhodopsin and metarhodopsin: there are two negative charges in the chromophore-binding site, one directly hydrogen bonded to the Schiff base nitrogen and a second near carbon-13. The interaction of this second charge with the chromophore in octopus rhodopsin is weaker than in bovine, while in metarhodopsin it is as strong as in bovine. 相似文献
6.
Dr. Kazuo Tamura Masanori Takeuchi Nobuyuki Hirakawa Kiyokazu Toyoda Masaru Minoda 《Biotherapy》1990,2(3):223-226
The 35-year-old man with myelodysplastic syndrome (MDS) and granulocytopenia with dry cough and high fever was eventually found to have a left perinephric abscess ofStaphylococcus aureus. He underwent left nephrectomy and drainage of perinephric space in conjunction with appropriate antibiotics. However, because of persistent granulocytopenia,Staph. aureus never cleared up with formation of only poor granulation. Recombinant human granulocyte colony-stimulating factor (G-CSF) was added to the above treatment leading to prompt improvement in granulocytopenia and emergence of the good granulation tissue. G-CSF will probably become one of the important agents in treating MDS with granulocytopenia. 相似文献
7.
Summary Seventeen cultivars belonging to the genus Dianthus were examined for protoplast isolation, culture and shoot regeneration under the same conditions. These included D. caryophyllus, D. chinensis, D. barbatus, D. plumarius, D. superbus and D. japonicus as well as interspecific hybrid cultivars (D. caryophyllus x D. chinensis and D. chinensis x D. barbatus). In all cultivars, viable protoplasts were isolated at high yields from leaves of axenic shoot cultures and some of these protoplasts divided and formed colonies. However, shoot regeneration frequencies were markedly different among the species. High frequency shoot regeneration was obtained from D. chinensis and interspecific hybrid cultivars, while only low frequency or no shoot regeneration was obtained from other species.Abbreviations MS
Murashige and Skoog (1962)
- FW
fresh weight
- MES
2-N-morpholinoethane sulfonic acid
- FDA
fluoroscein diacetate
- NAA
1-naphthaleneacetic acid 相似文献
8.
Keiko Mori Kazuho Hirata Masaru Kawabuchi Manabu Nakashima Takeshi Watanabe 《Immunogenetics》1991,33(2):101-107
A monoclonal antibody (mAb) TP-3 has been established by immunizing rats with the BALB/c mouse thymic epithelial cell line TEL-2. The TP-3 antigen is expressed on stroma cells of thymus, spleen, and lymph node in syngeneic BALB/c mice (H-2
d
). This antigen is also expressed at a low level on the cell surface of immature thymocytes, and at a high level on mature T and B cells. In allogeneic mice such as C57BL/6 (H-2
b
) or C3H (H-2
k
), no cells expressed the TP-3 antigen. Using H-2 congenic mice, reactivity with mAb TP-3 was found to map to a region of H-2D
d
L
d
or between D
d
and Qa, suggesting that TP-3 is a major histocompatibility complex (MHC) class I antigen. However, immunoprecipitation analysis indicated that this antigen is not identical to the classical mouse class I molecules in terms of molecular size, antigenicity, and tissue distribution. 相似文献
9.
Gene structure and expression of a tobacco endochitinase gene in suspension-cultured tobacco cells 总被引:8,自引:0,他引:8
We have isolated and characterized the genomic clone CHN50 corresponding to tobacco basic endochitinase (E.C.3.2.1.14). DNA sequence and blotting analysis reveal that the coding sequence of the gene present on CHN50 is identical to that of the cDNA clone pCHN50 and, moreover, the CHN50 gene has its origin in the progenitor of tobacco, Nicotiana sylvestris. Tobacco basic chitinases are encoded by a small gene family that consists of at least two members, the CHN50 gene and a closely related CHN17 gene which was characterized previously. By northern blot analysis, it is shown that the CHN50 gene is highly expressed in suspension-cultured tobacco cells and the mRNA accumulates at late logarithmic growth phase. To identify cis-DNA elements involved in the expression of the CHN50 gene in suspensioncultured cells, the chimeric gene consisting of 1.1 kb CHN50 5 upstream region fused to the coding sequence of -glucuronidase (GUS) was introduced by electroporation into protoplasts isolated from suspension-cultured tobacco cells. Transient GUS activity was found to be dependent on the growth phase of the cultured cells, from which protoplasts had been prepared. Functional analysis of 5 deletions suggests that the distal region between -788 and -345 contains sequences that potentiate the high-level expression in tobacco protoplasts and the region (-68 to -47) proximal to the TATA box functions as a putative silencer. 相似文献
10.
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