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1.
Nobumitsu Kawakubo 《Journal of plant research》1990,103(1):57-66
The morphology and function of the flowers of three species of the genusCallicarpa, C. glabra, C. nisnimurae andC. subpubescens, endemic to the Bonin Islands, revealed that all three species were dioecious. Male plants had short-styled flowers with
sterile ovaries, while female plants had long-styled flowers with non-germinating inaperturate pollen grains. Such dioecism
has never been reported from the family Verbenaceae. This curious sexual system with non-germinating pollen grains may have
been maintained as a reward to insect pollinators. 相似文献
2.
Ryozo Oishi Naoto Adachi Keishi Okada Nobuyuki Muroi Kiyomi Saeki 《Journal of neurochemistry》1990,55(6):1899-1904
To clarify the regulation of central histaminergic (HAergic) activity by cholinergic receptors, the effects of drugs that stimulate the cholinergic system on brain histamine (HA) turnover were examined, in vivo, in mice and rats. The HA turnover was estimated from the accumulation of tele-methylhistamine (t-MH) during the 90-min period after administration of pargyline (65 mg/kg, i.p.). In the whole brain of mice, oxotremorine, at doses higher than 0.05 mg/kg, s.c., significantly inhibited the HA turnover, this effect being completely antagonized by atropine but not by methylatropine. A large dose of nicotine (10 mg/kg, s.c.) also significantly inhibited the HA turnover. This inhibitory effect was antagonized by mecamylamine but not by atropine or hexamethonium. A cholinesterase inhibitor, physostigmine, at doses higher than 0.1 mg/kg, s.c., significantly inhibited the HA turnover. This effect was antagonized by atropine but not at all by mecamylamine. None of these cholinergic antagonists used affected the steady-state t-MH level or HA turnover by themselves. In the rat brain, physostigmine (0.1 and 0.3 mg/kg, s.c.) also decreased the HA turnover. This inhibitory effect of physostigmine was especially marked in the striatum and cerebral cortex where muscarinic receptors are present in high density. Oxotremorine (0.2 mg/kg, s.c.) and nicotine (1 mg/kg, s.c.) also decreased the HA turnover in the rat brain. However, these effects showed no marked regional differences. These results suggest that the stimulation of central muscarinic receptors potently inhibits the HAergic activity in the brain and that strong stimulation of central nicotinic receptors can also induce a similar effect. 相似文献
3.
Suzuki Y Murakami T Kawakubo K Haruna Y Takenaka K Goto S Makita Y Ikawa S Gunji A 《Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology》1994,1(1):P57-P58
To this day, many studies have suggested that prolonged bed rest (BR) affects on muscle mass and strength not only in gravity muscles but also in ungravity muscles. However, it is still unclear whether the decrease in regional muscle strength after BR is due to the alterations in the corresponding muscle mass, or not. On the other hand, if BR decreases the mass of antigravity muscles (UGM) as well as muscle strength and then increases tissue compliance of the antigravity muscles, orthostatic tolerance capacity will be decreased by the reduction in cardiac output (CO) in spite of the increase in myocardial contractility because the more decrease in venous return due to the more increase in blood pooling within the compliant tissues of the lower body. However, this is also unclear. To make these questions clear, the present study investigated the regional muscle mass and strength and orthostatic tolerance capacity before and after 20 days of bed rest in young subjects. 相似文献
4.
Bonde-Petersen F Suzuki Y Kawakubo K Gunji A 《Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology》1994,1(1):P27-P28
It has been generally accepted that pooling of the blood in the legs is one reason for the orthostatic intolerance experienced after space flights. This is also the reasoning behind the application of anti-G suits during reentry after space flights. Fighter pilots also use the anti-G suit, the hypothesis being that this prevents the pooling of blood in the legs. In order to investigate if immobilization during bed rest would induce peripheral cardiovascular deconditioning we measured capillary filtration rate, venous compliance, and blood flow in arms and legs during bed rest. 相似文献
5.
Molecular cloning of two tandemly arranged peroxidase genes from Populus kitakamiensis and their differential regulation in the stem 总被引:2,自引:0,他引:2
Keishi Osakabe Hirokazu Koyama Shinya Kawai Yoshihiro Katayama Noriyuki Morohoshi 《Plant molecular biology》1995,28(4):677-689
A genomic library was prepared from Populus kitakamiensis and screened with the cDNA for an anionic peroxidase from P. kitakamiensis. One genomic clone was isolated that contained two tandemly oriented genes for anionic peroxidases, prxA3a and prxA4a. Both genes consisted of four exons and three introns; the introns had consensus nucleotides, namely, GT and AG, at their 5 and 3 ends, respectively. The prxA3a and prxA4a genes encoded 347 and 343 amino acid residues, respectively, including putative signal sequences at the amino-termini. Putative promoters and polyadenylation signals were found in the flanking regions of both genes. The sequence of the coding region of prxA3a was completely identical to that of the cDNA clone pA3, whereas the sequence of the coding region of prxA4a was only 73% identical to that of the cDNA clone pA3. Northern blot analysis showed that the patterns of expression of the mRNAs that corresponded to prxA3a and prxA4a differed in stems of P. kitakamiensis. 相似文献
6.
Immunological responses of hamsters in the acquired immune state to Mycoplasma pneumoniae infection 总被引:1,自引:0,他引:1
E Hayatsu Y Kawakubo M Yayoshi M Araake M Wakai A Yoshida M Yoshioka Y Nishiyama 《Microbiology and immunology》1981,25(12):1255-1263
Protective effects of vaccination of hamsters against Mycoplasma pneumoniae infection, evaluated according to the recovery of mycoplasmas and histopathological changes in the respiratory tract after challenge infection, persisted for at least 6 months after the final vaccination. Serum antibody levels reached a maximum in the second week after the last vaccination and decreased markedly between the first and the third months, but increased again in sera obtained from animals given booster injections. Metabolism-inhibiting antibodies were detected in bronchial washings of animals showing high resistance obtained by vaccinal or passive immunization. Antiserum transfer was also effective for protection but cell-mediated immune responses were not demonstrated in any animals up to 6 months after the vaccination. Even after 10 months, suppression of both mycoplasmal proliferation and lung lesions was apparent, and a single dose of the vaccine induced a significant booster effect. These findings suggest that (1) humoral immunity is more important than cell-mediated immunity in resistance of hamsters to M. pneumoniae pneumonia, and (2) the antibody secreted in the respiratory tract may be involved in the local defense mechanisms. 相似文献
7.
Keishi Abe Minoru Yasujima Satoru Chiba Tetsuo Saito 《Prostaglandins & other lipid mediators》1977,14(3):513-521
Urinary excretion of prostaglandin E was measured radioimmunologically in 19 healthy persons ( 15 men and 4 women ) and in 16 patients ( 10 men and 6 women ) with essential hypertension before and after the administration of furosemide. The excretion rates were increased from 26.3±3.0 to 64.5±11.3 ng/hr in the former and from 11.9±2.7 to 26.9±85 ng/hr in the latter. There was a significant difference between them, healthy subjects showing a greater increase than patients with essential hypertension.There was an obvious sexual difference in urinary excretion of prostaglandin. In men, greater increase in the excretion rates was found than in the women. Greater increases were also obtained in healthy men than in hypertensive men and in healthy women than in hypertensive women. The present results suggest that furosemide enhances urinary excretion of prostaglandin E by mechanisms which entails either an increase in prostaglandin synthesis or a decrease in renal metabolism. 相似文献
8.
Keishi Abe Yoichi Otsuka Minoru Yasujima Satoru Ciba Masahide Seino Nobuo Irokawa Kaoru Yoshinaga Fumio Hirata Shiro Ohki Nobuhiko Nakazawa Toshio Hanyu 《Prostaglandins & other lipid mediators》1976,12(5):843-848
The excretion rates of main urinary metabolite of PG F2α were measured radioimmunologically in 4 healthy persons and in 13 essential hypertensives. The resting values were 9.3±0.73 in the former and 10.4±2.17 ng/min in the latter. There was no significant differences between them. The excretion of the metabolite decresed prominently after the administration of furosemide. The percent decrease was 57% in healthy persons and 70% in essential hypertension. The percent result supports that furosemide inhibit the catabolism of PG F2α. 相似文献
9.
During infection with Schistosoma, serious hepatic disorders are induced in the host. The liver possesses unique immune systems composed of specialized cells that differ from those of other immune competent organs or tissues. Host immune responses change dramatically during Schistosoma mansoni infection; in the early phase, Th1-related responses are induced, whereas during the late phase Th2 reactions dominate. Here, we describe unique T cell populations induced in the liver of mice during the period between Th1- and Th2-phases, which we term the transition phase. During this phase, varieties of immune cells including T lymphocytes increase in the liver. Subsets of CD4+ T cells exhibit unique cytokine production profiles, simultaneously producing both IFN-γ and IL-13 or both IFN-γ and IL-4. Furthermore, cells triply positive for IFN-γ, IL-13 and IL-4 also expand in the S. mansoni-infected liver. The induction of these unique cell populations does not occur in the spleen, indicating it is a phenomenon specific to the liver. In single hepatic CD4+ T cells showing the unique cytokine profiles, both T-bet and GATA-3 are expressed. Thus, our studies show that S. mansoni infection triggers the induction of hepatic T cell subsets with unique cytokine profiles. 相似文献
10.
Keishi Shimokawa Yoshinori Ueda Zenzaburo Kasai 《Bioscience, biotechnology, and biochemistry》2013,77(11):2021-2024
ABSTRACTJapanese apricot, Prunus mume Sieb. et Zucc., biosynthesizes the l-phenylalanine-derived cyanogenic glucosides prunasin and amygdalin. Prunasin has biological properties such as anti-inflammation, but plant extraction and chemical synthesis are impractical. In this study, we identified and characterized UGT85A47 from Japanese apricot. Further, UGT85A47 was utilized for prunasin microbial production. Full-length cDNA encoding UGT85A47 was isolated from Japanese apricot after 5?- and 3?-RACE. Recombinant UGT85A47 stoichiometrically catalyzed UDP-glucose consumption and synthesis of prunasin and UDP from mandelonitrile. Escherichia coli C41(DE3) cells expressing UGT85A47 produced prunasin (0.64 g/L) from racemic mandelonitrile and glucose. In addition, co-expression of genes encoding UDP-glucose biosynthetic enzymes (phosphoglucomutase and UTP-glucose 1-phosphate uridiltransferase) and polyphosphate kinase clearly improved prunasin production up to 2.3 g/L. These results showed that our whole-cell biocatalytic system is significantly more efficient than the existing prunasin production systems, such as chemical synthesis. 相似文献