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11.
Junzou Hiratsuka Hiroaki Shimada Robert Whittier Takashi Ishibashi Masahiro Sakamoto Masao Mori Chihiro Kondo Yasuko Honji Chong-Rong Sun Bing-Yuan Meng Yu-Qing Li Akira Kanno Yoko Nishizawa Atsushi Hirai Kazuo Shinozaki Masahiro Sugiura 《Molecular & general genetics : MGG》1989,217(2-3):185-194
Summary The entire chloroplast genome of the monocot rice (Oryza sativa) has been sequenced and comprises 134525 bp. Predicted genes have been identified along with open reading frames (ORFs) conserved
between rice and the previously sequenced chloroplast genomes, a dicot, tobacco (Nicotiana tabacum), and a liverwort (Marchantia polymorpha). The same complement of 30 tRNA and 4 rRNA genes has been conserved between rice and tobacco. Most ORFs extensively conserved
betweenN. tabacum andM. polymorpha are also conserved intact in rice. However, several such ORFs are entirely absent in rice, or present only in severely truncated
form. Structural changes are also apparent in the genome relative to tobacco. The inverted repeats, characteristic of chloroplast
genome structure, have expanded outward to include several genes present only once per genome in tobacco and liverwort and
the large single copy region has undergone a series of inversions which predate the divergence of the cereals. A chimeric
tRNA pseudogene overlaps an apparent endpoint of the largest inversion, and a model invoking illegitimate recombination between
tRNA genes is proposed which accounts simultaneously for the origin of this pseudogene, the large inversion and the creation
of repeated sequences near the inversion endpoints. 相似文献
12.
Hajime Otani Hitomi Otan Masao Morita Dipak K. Das 《Molecular and cellular biochemistry》1989,90(2):111-120
We investigated the effect of Ca2+ overload on the phospholipase C-catalyzed hydrolysis of phosphoinositides in the rat left ventricular papillary muscle. Ca2+ overload on the papillary muscle was induced by treatment with 0.3 mM ouabain in Ca2+-containing medium following either Ca2+-containing or Ca2+-free superfusion. The phosphoinositide breakdown was evaluated by determining accumulations of [3H]inositol phosphates ([3H]IPs) in the tissues prelabeled with [3H]inositol. Ca2+ repletion following Ca2+-free superfusion resulted in a rapid but small increase in resting tension that was not followed by contracture, nor was it associated with a significant increase in [3H]IPs accumulations. Treatment with ouabain following Ca2+-containing superfusion increased resting tension after a lag period of several minutes and produced contracture associated with an increase in [3H]IPs accumulations. The ouabain induced increases in resting tension, and accumulations of [3H]IPs were significantly potentiated by prior Ca2+-free superfusion instead of Ca2+-containing superfusion. There was a significant positive correlation between increases in resting tension and the phosphoinositide breakdown. The increased resting tension and the accumulations of [3H]IPs were not antagonized by treatments with prazosin plus atropine or indomethacin, but were abolished by superfusion with Ca2+-free buffer solution. Although the enhanced phospholipase C-catalyzed hydrolysis of phosphoinositides appears to be a consequence rather than a cause of increased intracellular Ca2+, such a biochemical change may provoke a positive feedback mechanism to develop the muscle contracture through the putative intracellular messenger action of inositol triphosphate and diacylglycerol.Abbreviations [3H]IPs
[3H]Inositol Phosphates
- IP
Inositol Phosphate
- IP2
Inositol Bisphosphate
- IP3
Inositol Trisphosphate
- PI
Phosphatidylinositol
- PI-4-P
Phosphatidylinositol-4-phosphate
- PI-4,5-P2
Phosphatidylinositol 4,5-bisphosphate
- PRZ
Prazosin
- ATR
Atropine
- INDO
Indomethacin
- min
Minutes 相似文献
13.
We recently reported that primary fetal bovine Kidney (PFBK) cells were consistently more sensitive to the cytotoxic effects of fusarium T-2 toxin than Madin-Darby bovine kidney (MDBK) cells in culture. The present report examined the influence of T-2 on selected biochemical parameters of these two culture types. T-2 toxin inhibited incorporation of labeled thymidine, uridine, and leucine in both culture types; at lower concentrations of the toxin, PFBK cells were affected to a greater extent than MDBK cells. T-2 toxin inhibited both the transport of thymidine as well as thymidine incorporation into macromolecules in MDBK cells during initial periods, but did not affect uridine incorporation. The cellular enzymes, K+- dependent phosphatase and succinic dehydrogenase were inhibited in MDBK but not in PFBK cultures; acid phosphatase was not influenced in either culture types. In a cell-free system none of the above enzymes were affected by T-2 until the toxin concentration exceeded 10?5M. 相似文献
14.
Toshiho Nishita Hidetoshi Oshige Hiroharu Matsushita Yutaka Kano Masao Asari 《The Histochemical journal》1989,21(1):8-14
Summary Carbonic anhydrase III has been localized using the avidin-biotin-glucose oxidase complex (ABC) method in the submandibular gland of the rat and hamster. This isozyme, which is predominant in skeletal muscle, was observed in intercalated duct, striated duct and excretory duct cells in the rat submandibular glands. In contrast, only some striated duct cells in hamster submandibular glands were stained. 相似文献
15.
16.
Mitoshi Yokota Yutaka Tagawa Daikichi Okada Tooru Yasutake Yoshikazu Mine Hiroshi Ishikawa Kousei Miyashita Masao Tomita Sumihiro Tabuchi 《Biotherapy》1990,2(3):207-212
Pre- and postoperative intradermal administration of OK-432 enhanced the SU-PS skin reaction in patients with gastric cancer, but failed to prevent a fall in the NK activity induced by the operation.The change in NK activity was not associated with a change in the proportion of Leu 7-positive cells, but was related to Leu 11a-positive cells. Intradermal injection of OK-432 increased the proportion of Leu 7-positive cells in the patients in whom they accounted for less than 20% of lymphocyte population. The case was the same with Leu 11a-positive cells.Intravenous injection of OK-432 tended to increase suppressor-inducer T cells (CD4+2HA+ cells), B cells and Leu 7-positive cells. Particularly, the proportions of OK-M1-positive cells and MHC class II antigen-positive cells increased in all patients. Immunotherapy with OK-432 given intravenously at a dose of 0.1 KE appeared to be safe because no side effects were essentially observed. 相似文献
17.
Effect of exogenous fatty acids on zygote formation in Saccharomyces cerevisiae was studied. Arachidonic and oleic acids considerably stimulated zygote formation, but other fatty acids tested, linoleic, linolenic, stearic and palmitic acids, did not. Pretreatment experiments with arachidonic acid showed that the stimulation of zygote formation by the fatty acid required the presence of mating pheromone.Abbreviations YPD
yeast-peptone-dextrose medium
- A530
absorbance at 530 nm 相似文献
18.
19.
Masao Eura Tatsuhiko Maehara Tsutomu Ikawa Takeru Ishikawa 《Cancer immunology, immunotherapy : CII》1988,27(2):147-153
Summary Cytotoxicity was induced in lymphocytes (CL) from 10 out of 15 patients by autologous mixed lymphocyte tumor cell culture and further cultivation with recombinant interleukin-2. In cells from 3 of the 10 patients, cytotoxicity was suppressed by more than 50% when autologous peripheral blood mononuclear cells (PBMC) from the patients with large tumors were added to the autologous killing system. The cells responsible for suppressing the cytotoxicity in the effector phase were adherent or nonadherent to plastic depending on the patient examined. The T cell fraction from 1 patient significantly suppressed the cytotoxic activity, and this suppression was seen only in the autologous system. On the other hand, plastic adherent cells but not T cells from PBMC of 2 subjects suppressed the cytotoxic activity of CL. The reason why the main cell population suppressing the CL activity differed among the patients is unclear. However, the findings that the suppression was mostly abrogated following resection of the tumor mass suggested that suppressor cells, either of macrophage lineage or T cells, are induced in patients with a large tumor mass. This speculation is supported by the finding that the PBMC from a patient with tumor recurrence regained the suppressive activity. 相似文献
20.
Masao Ohkuchi Masami Tsukamoto Toru Yokoyama Masami Shiratsuchi Yasumi Uchida 《Prostaglandins & other lipid mediators》1988,36(6)
To isolate and identify the plasma factor which stimulates prostaglandin I 2 production by rat aortic ring, a human plasma fraction which showed a major stimulating activity on prostaglandin I 2 production was purified by ultrafiltrate, Sephadex G-10 gel filtration and QAE-Sephadex column chromatography. The purified plasma factor was identified as acid by its ultraviolet and infrared absorption spectroscopy, and 1H nmr and 13C nmr spectroscopy. The stimulating activity of the purified plasma factor and that of authentic uric acid coincided with each other. The stimulating potency of uric acid at its physiological concentration in human plasma (about 50 μg/ml) was half of the deproteinized human plasma, and was about 30 fold stronger than that of L-tryptophan, a cofactor of prostaglandin hyperoxidase. 相似文献