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41.
DNA immunization: Effects of vehicle and route of administration on the induction of protective antiviral immunity 总被引:2,自引:0,他引:2
Masayuki Yokoyama Jie Zhang J.Lindsay Whitton 《FEMS immunology and medical microbiology》1996,14(4):221-230
Abstract The effectiveness of DNA immunization has been demonstrated in several model systems, usually following intramuscular injection of DNA in saline, or topical administration to the skin. In this study we have compared DNA delivered by three routes (intramuscular, intravenous, and intraperitoneal) and, for each route, in two vehicles (cationic liposome complex and pH sensitive liposome). These two lipid vehicles were evaluated because they are frequently used in gene therapy studies, but their immunogenicity has not been extensively studied. Each of these six combinations has been evaluated not only by assay of marker gene expression in a variety of tissues, but also by measurement of biologically-relevant parameters of immunity induction of antibodies, cytotoxic T lymphocytes, and protection against viral challenge. By both criteria (marker gene expression and induced immunity), the outcomes vary markedly among the six combinations. The combination leading to maximal marker gene expression (DNA with cationic lipid, administered i.v.) also induces detectable antibodies and CTL, and is the only one of the six combinations to induce immune responses comparable to those seen following i.m. injection of DNA in saline. However, marker gene expression can be detected in other combinations in the absence of induced immunity thus the value of marker gene expression in predicting the protection induced by a microbial antigen is questionable suggesting that, when evaluating various promoter constructs, marker gene expression may not adequately replace the direct measurement of biological outcomes. 相似文献
42.
Photo-induced activation of cytochrome P450/reductase fusion enzyme coupled with spinach chloroplasts 总被引:1,自引:0,他引:1
Young-Sug Kim Masayuki Hara Kazunori Ikebukuro Jun Miyake Hideo Ohkawa Isao Karube 《Biotechnology Techniques》1996,10(10):717-720
Summary Photoactivation of cytochrome P450 monooxygenase was studied using a combination of spinach chloroplasts and yeast microsomes containing rat P4501A1/yeast reductase fusion enzyme. Under illumination, in the reaction mixture, NADP was reduced, transferring electrons to the P450/reductase fusion enzyme to convert 7-ethoxycoumarin to 7-hydroxycoumarin. 相似文献
43.
44.
Eight diatom species (Chaetoceros pseudocurvisetus Mang ., Stephanodiscus hantzschii Grun ., Skeletonema costatum ( Grev.) Cleve , Asterionella formosa Hass ., Thalassiosira nordenskioeldii Cleve , Detonula confervacea ( Cleve) Gran , Chaetoceros sp., and Nitzschia frigida Grun.) were isolated from various temperature environments ranging from temperate to the Arctic, and their growth responses to temperature were determined. Each species grew over a different temperature range. The lower and upper limits of each species varied from −1.8° to 20° C and from 2° to 30° C, respectively. The width of the growth range of each species. also varied from 3.8° to 25° C, and the growth of these species was observed, as a whole, between a wide temperature range from −1.8° to 30° C .
Within the growth temperature ranges, the growth rate of each species increased with temperature until reaching a maximum, which was followed by a steep decrease up to the upper limit of the growth range. As a result, each species showed a maximum rate at the temperature very near to the upper limit, which was generally higher than the isolation temperature. The specific growth rates were compared among the eight species. The interspecific maximum rate at each temperature exhibited an exponential increase with a Q10 = 1.48. The relative growth rates of each species were calculated by normalizing the specific growth rates with the interspecific maximum rate at each respective temperature. The higher relative growth rates tended to occur at the isolation temperature of each species, suggesting that temperature is a significant control on species distributions in nature . 相似文献
Within the growth temperature ranges, the growth rate of each species increased with temperature until reaching a maximum, which was followed by a steep decrease up to the upper limit of the growth range. As a result, each species showed a maximum rate at the temperature very near to the upper limit, which was generally higher than the isolation temperature. The specific growth rates were compared among the eight species. The interspecific maximum rate at each temperature exhibited an exponential increase with a Q
45.
Tobacco Nuclear Genes for Photosystem I Subunits, psaD, psaE and psaH Share an Octamer Motif Bound with Nuclear Proteins 总被引:1,自引:0,他引:1
In Nicotiana sylvestris, nuclear-encoded photosystem I (PSI)genes, psaD, psaE and psaH, share an octamer motif bound withthree phosphoproteins. This motif is not found in the chloroplastgenome. From the view point of endosymbiont hypothesis, theseresults suggest that a set of ancient PSI genes acquired a commoncis-element in the nucleus after they were transferred fromthe ancestral organelle. (Received March 20, 1995; Accepted August 9, 1995) 相似文献
46.
Records of exotic turbellarian species found in Japan are reviewed from taxonomic and karyological viewpoints. Temnocephala minor Haswell, 1888, an ectocommensal on a freshwater crayfish of Australia, was found from culture ponds of Cherax tenuimanus (introduced from W. Australia) in Kagoshima Prefecture. T. minor had the chromosome number of 2x = 18 (2sm + 2m + 2m + 2sm + 2m + 2m + 2m + 2sm + 2m). The following 3 species of exotic freshwater triclads were recorded from tanks and ponds used for tropical fish culture: Dugesia austroasiatica Kawakatsu, 1985 (2x = 16), Dugesia tigrina (Girard, 1850) (2x = 16) and Rhodax? sp. (3x = 24; 3x = 24 &; 3x + 1LB + 1SB = 25 + 1SB). The following 3 species of exotic terrestrial triclads were recorded: Bipalium nobile Kawakatsu et Makino, 1982 (2x = 10), Bipalium kewense Moseley, 1878 (2x = 18), and Platydemus manokwari de Beauchamp, 1962 (n = 6, 2x = 12). An extensive occurrence of P. manokwari in the Southwest Islands of Japan may be due to an unexpected introduction of the animal in very recent years. 相似文献
47.
Tadashi II Masayuki Kubota Takashi Hirano Mamoru Ohashi Keiichi Yoshida Sakaru Suzuki 《Glycoconjugate journal》1995,12(3):282-289
The fast atom bombardment (FAB) collision induced dissociation (CID)-mass spectrometry/mass spectrometry (MS/MS) technique was successfully applied to characterize and identify the structures of the immunoreactive trisulfated and tetrasulfated tetrasaccharides that were obtained from the chondroitin sulfate in a shark fin using a treatment with chondroitinase ABC.Abbreviations FABMS
fast atom bombardment mass spectrometry
- CID
collision induced dissociation
- MS/MS
mass spectrometry/mass spectrometry
- UA2S-GalNAc6S
2-acetamido-2-deoxy-3-O-(2-O-sulfo--d-gluco-4-enepyranosyluronic acid)-6-O-sulfo-d-galactose
- UA-GalNAc4S
2-acetamido-2-deoxy-3-O-(-d-gluco-4-enepyranosyluronic acid)-4-O-sulfo-d-galactose
- UA-GalNAcDiS
2-acetamido-2-deoxy-3-O-(-d-gluco-4-enepyranosyluronic acid)-4,6-di-O-sulfo-d-galactose 相似文献
48.
Masayuki Kobayashi Marc Garcia-Elias Ladislav Nagy Marco J. P. F. Ritt Kai-Nan An William P. Cooney Ronald L. Linscheid 《Journal of biomechanics》1997,30(11-12)
The changes in carpal bone alignment secondary to the aplication of an axial compressive load through the major wrist motor tendons while the wrist is kept in neutral position (isometric loading) have been investigated on 13 fresh cadaver specimens using a biplanar radiographic method of kinematic analysis. The scaphoid, lunate and triquetrum rotate an average of 5.1, 4.2 and 3.8°, respectively, around different ‘screw displacement axes’, all implying flexion, radial deviation and supination. Based on these findings, a new interpretation of the mechanism by which the wrist remains stable under physiologic loads is provided. 相似文献
49.
Toda Hideshige; Takahashi Masayuki; Ichimura Shun-ei 《Journal of plankton research》1984,6(4):647-662
The effect of temperature on post-embryonic growth of Neomysisintermedia was investigated under unlimited food conditionsin the laboratory. The effect of temperature on the size ofnewly released animals was negligibly small, but body size wasinversely related to temperature in adults. This was mainlycaused by the difference in the number of molts before maturation.The specific growth rate of N. intermedia increased exponentiallywith a temperature coefficient, Q10 of 4.6 from 0.018 d13C to 0.21 d1 at 20C in juveniles, and with a temperaturecoefficient of 2.7 from 0.006 d1 at 3C to 0.05 d1at 25C in adults. The rate in juveniles levelled off above20C, and dropped at 29C. Brood size and brood interval decreasedwith temperature increase, while the daily specific reproductionrate increased. The specific growth rate of gravid females,including production of egg matter, increased exponentiallywith a temperature coefficient of 3.3 from 0.015 d1 at10C to 0.093 d1 at 25C. The present laboratory experiments confirmed the temperaturecontrol on the growth of N. intermedia suggested in a hyper-eutrophiclake. 相似文献
50.
Effects of Preillumination on Dark Nitrogen Fixation and Respiration by Anabaena Cylindrica 总被引:1,自引:0,他引:1
In whole filaments of Anabaena cylindrica dark nitrogen-fixingactivity (measured as acetylene reduction) and respiration increasedwith the light intensity of a fixed period of preillumination,saturating at ca. 10,000 lux. With saturating light during preillumination,the amount and duration of dark nitrogen-fixing activity increasedwith length of preillumination, but respiration declined rapidlyin the dark. At dark respiration rates below 250 nmol O2 uptake mg protein1?h1(State 1) no significant nitrogen-fixing activity is observed.From 250 to 550 nmol O2 uptake?mg protein1?h1(State 2), nitrogen-fixing activity depends on O2 uptake whileabove 550 nmol O2 uptake?mg protein1?h1 (State3), nitrogen-fixing activity no longer increases with furtherincrease in O2 uptake rate. (Received June 18, 1983; Accepted November 10, 1983) 相似文献