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1.
W Nakamura K Komatsu K Kageyama 《Comptes rendus des séances de la Société de biologie et de ses filiales》1985,179(4):558-562
Comparison was made between the effects of local irradiation of gamma rays, s. c. injection of cis-diamminedichloroplatinum (II) (CDDP), systemic hyperthermia and their combinations on the i. m. transplanted murine mastocytoma. Increase of the mean survival time (M. S. T.) by a factor of 1.72 and of 1.68 was achieved by a single irradiation at 20 Gy, given on day 5 after transplantation, and by injections of CDDP at 2 mg/kg, given s. c. on days 5 and 12 after transplantation, respectively. Increase of M. S. T. by a factor of 1.10 which was achieved with systemic hyperthermia of 41.8 degrees C of the core body temperature for 5 min, given twice, on days 5 and 12 after transplantation, was not statistically significant. The most effective one among all possible combinations within the 3 modalities was that of radiation and CDDP. Increase of M. S. T. was by a factor of 4.01. 相似文献
2.
M. Nakamura M. Oda Y. Yonei N. Tsukada H. Komatsu K. Kaneko M. Tsuchiya 《Histochemistry and cell biology》1985,83(6):479-487
Summary The muscarinic cholinergic innervation of the rat gastric mucosa was investigated by localizing the muscarinic receptors using a tritiated muscarinic antagonist, pirenzepine. Radioautography was performed by freeze drying stomach tissue, which was then embedded in Epon and wet sectioned with ethylene glycol, and dry mounting on emulsion film by the wire-loop method to prevent loss of the labelled substance during fixation and the radioautographic procedure. Light and electron microscopy showed that the specific pirenzepine-binding sites were localized predominantly on parietal cells, chief cells and perivascular plexuses. Analysis of the grain distribution on parietal cells revealed that the silver grains corresponding to the pirenzepine-binding sites were mainly on the basolateral plasma membrane. On the other hand, the surface mucous or mucous neck cells had few pirenzepine-binding sites. 相似文献
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The purpose of this paper was to examine the effect of chair restraint on plasma enzyme values in the rhesus monkey. Six monkeys were restrained to the monkey chair for eight hours. Creatine phosphokinase (CK) value increased significantly three hours after the onset of restraint and LDH value did eight hours after the onset of restraint. The increase in CK, GOT and GPT values continued for 1 or 2 days after the release from restraint. On the other hand, these plasma enzyme values in non-restraint monkeys showed almost no changes. These results indicate that it is necessary to establish a proper method for the adjustment to chair restraint in the rhesus monkey. 相似文献
5.
A peptide fragment Fr. 17 (Lys1-Cys-Asn27 Leu129-Cys-Ala122) of hen egg white lysozyme (HL) was previously found to retain at least one antigenic determinant region of the native protein. In this work a highly purified preparation of Fr. 17, contaminated with less than 0.01% HL and less than 1% of other fragments was found to be strongly immunogenic to rabbits. The kinetic patterns of antibody formation against Fr.17, assayed by passive hemagglutination (PHA), were quite different from those of antibody formation against HL. The specificity of the antibody elicited to Fr. 17 was mainly directed to the Fr. 9-10-a region (Ala11-Asn27) while that of the antibody elicited to the Fr. 17 region in native HL was directed to the Fr. 15-b region (Lys1-Cys-Ala10 Leu129-Cys-Trp123). It is concluded that in the process of antibody formation, the recognition of the Fr. 17 region in native HL is different from that of fragment Fr. 17. 相似文献
6.
Sun X Komatsu T Lim J Laslo M Yolitz J Wang C Poirier L Alberico T Zou S 《Aging cell》2012,11(5):783-793
Reactive oxygen species (ROS) modulate aging and aging-related diseases. Dietary composition is critical in modulating lifespan. However, how ROS modulate dietary effects on lifespan remains poorly understood. Superoxide dismutase 1 (SOD1) is a major cytosolic enzyme responsible for scavenging superoxides. Here we investigated the role of SOD1 in lifespan modulation by diet in Drosophila. We found that a high sugar-low protein (HS-LP) diet or low-calorie diet with low-sugar content, representing protein restriction, increased lifespan but not resistance to acute oxidative stress in wild-type flies, relative to a standard base diet. A low sugar-high protein diet had an opposite effect. Our genetic analysis indicated that SOD1 overexpression or dfoxo deletion did not alter lifespan patterns of flies responding to diets. However, sod1 reduction blunted lifespan extension by the HS-LP diet but not the low-calorie diet. HS-LP and low-calorie diets both reduced target of rapamycin (TOR) signaling and only the HS-LP diet increased oxidative damage. sod1 knockdown did not affect phosphorylation of S6 kinase, suggesting that SOD1 acts in parallel with or downstream of TOR signaling. Surprisingly, rapamycin decreased lifespan in sod1 mutant but not wild-type males fed the standard, HS-LP, and low-calorie diets, whereas antioxidant N-acetylcysteine only increased lifespan in sod1 mutant males fed the HS-LP diet, when compared to diet-matched controls. Our findings suggest that SOD1 is required for lifespan extension by protein restriction only when dietary sugar is high and support the context-dependent role of ROS in aging and caution the use of rapamycin and antioxidants in aging interventions. 相似文献
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8.
Shibao H Kutsukake M Fukatsu T 《Proceedings. Biological sciences / The Royal Society》2004,271(Z3):S71-S74
For evolution and maintenance of the social system of insect colonies, investment in the sterile caste should be adequately controlled in response to environmental cues. Recent developments using artificial diet rearing techniques have revealed an underlying mechanism of caste control in a gall-forming aphid, Tuberaphis styraci, which has a soldier caste in the second instar. Statistical analyses of field-collected galls detected a significant positive correlation between aphid density and soldier proportion in the natural colonies of T. styraci. Artificial diet experiments showed that soldiers are produced under crowded conditions. Detailed experiments demonstrated that soldiers are produced in a density-dependent manner rather than in a colony size-dependent manner. From these results, it was concluded that aphid density is the crucial cue that triggers soldier production in T. styraci. This study provides, to our knowledge, the first experimental demonstration of an environmental factor involved in aphid soldier differentiation. 相似文献
9.
Epidermal growth factor stimulates proliferation of mouse uterine epithelial cells in primary culture 总被引:1,自引:0,他引:1
Shiraga M Komatsu N Teshigawara K Okada A Takeuchi S Fukamachi H Takahashi S 《Zoological science》2000,17(5):661-666
Epidermal growth factor (EGF) is one of growth factors that are thought to mediate the stimulatory effects of estrogen on the proliferation of uterine epithelial cells. The present study was attempted to obtain direct evidence for the mitogenic effects of EGF on uterine epithelial cells, and to prove that EGF and EGF receptors are expressed in these cells. Mouse uterine epithelial cells were isolated from immature female mice and cultured with or without EGF for 5 days. EGF (1 to 100 ng/ml) significantly increased the number of uterine epithelial cells, and the maximal growth (141.9+/- 8.3% of controls) was obtained at a dose of 10 ng/ml. In addition, EGF (0.1 to 100 ng/ml) increased the number of DNA-synthesizing cells immunocytochemically detected by bromodeoxyuridine uptake to the nucleus. Northern blot analysis revealed that the uterine epithelial cells expressed both EGF mRNA (4.7 kb) and EGF receptor mRNAs (10.5, 6.6, and 2.7 kb) These results suggest that the proliferation of uterine epithelial cells is regulated by the paracrine and/or autocrine action of EGF. Our previous study demonstrated the mitogenic effect of IGF-I on uterine epithelial cells. To examine whether the EGF- and IGF-I signaling act at the same level in the regulation of the proliferation of uterine epithelial cells, the cultured cells were simultaneously treated with IGF-I and EGF. IGF-I was found to additively stimulate the mitogenic effects of EGF, suggesting that the EGF-induced growth of uterine epithelial cells is distinct from IGF-I-induced growth. 相似文献
10.
Toshio Yoshida Shigeru Muraki Hiroshi Kawamura Akira Komatsu 《Bioscience, biotechnology, and biochemistry》2013,77(3):343-352
The main component of Japanese Ho-leaf oil has been shown to be (?)-linalool (80~90%), and the following twenty minor constituents newly have been identified; methyl vinyl ketone, methyl isobutyl ketone, mesityl oxide, β-pinene, myrcene, (+)-limonene, cis- and trans-ocimene, n-hexanol, cis-3-hexenol, cis- and trans-linalool oxide, (?)-1-terpinen-4-ol, (+)-cis and (+)-trans-2,6,6-trimethyl-2-vinyl-5-hydroxytetrahydropyran, citronellol, nerol, (+)-β-selinene, (+)-tagetonol and (?)-trans-hotrienol. (+)-Tagetonol and (?)-trans-hotrienol have been demonstrated to be (+)-3,7-dimethyl-3-hydroxy-1-octen-5-one (III) and (3R)-(?)-trans-3,7-dimethyl-3-hydroxy-1,5,7-octatriene (IX), respectively. 相似文献