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101.
Expression of hepatitis B virus surface antigen in adult rat liver. Co-introduction of DNA and nuclear protein by a simplified liposome method. 总被引:7,自引:0,他引:7
K Kato M Nakanishi Y Kaneda T Uchida Y Okada 《The Journal of biological chemistry》1991,266(6):3361-3364
We established a simple and efficient method for gene transfer in vitro (to cultured cells) and in vivo (to an adult organ) using liposomes. Plasmid DNA and proteins were efficiently co-encapsulated in liposomes by agitation and sonication, and were co-introduced into cells by hemagglutinating virus of Japan (HVJ)-mediated membrane fusion. Introduction of the Escherichia coli beta-galactosidase gene with non-histone chromosomal protein high mobility group 1 (HMG1) into LLCMK2 cells resulted in about 3 times higher beta-galactosidase activity than that on introduction of the gene alone. Two days after injection of HVJ-liposomes containing the beta-galactosidase gene and HMG1 under the perisplanchnic membrane of adult rat liver, hepatic cells near the injection site were found by 5-bromo-4-chloro-3-indolyl beta-D-galactoside staining to have beta-galactosidase activity. After similar injection of HVJ-liposomes containing the hepatitis B virus surface antigen (HBsAg) gene and HMG1, HBsAg was detected in the serum for 9 days with a maximum of 25-45 ng/ml on day 2 after the injection. 相似文献
102.
Takuya Sugawara Mariko Chinzei Setsuko Numano Chifumi Kitazaki Munehiko Asayama 《Biotechnology letters》2018,40(5):829-836
Objective
A novel filamentous cyanobacterium, a photosynthesizing microorganism, was isolated from a river, and its unique features of flocculation and pentadecane production were characterized.Results
Microscopic observations and a phylogenetic analysis with 16S rDNA revealed that this strain was a Limnothrix species denoted as the SK1-2-1 strain. Auto cell-flocculation was observed when this strain was exposed to a two-step incubation involving a standing cultivation following a shaking preincubation. Flocculation was enhanced by blue light at a wavelength at 470 nm and irradiation for several hours to 1 day. Moreover, the strain exhibiting exponential cell growth may preferentially accumulate alkanes as pentadecane C15H32 alkane, which may be used as jet fuel, at a range of approximately 1% in the dry cell weight of flocculated cells.Conclusion
This is the first study on biofuel production using flocculated cells in which the specific manner of production may be regulated by cultivation conditions.103.
Akira Sawada Tetsuya Iwasaki Chitose Inoue Kana Nakaoka Takumi Nakanishi Junpei Sawada Narumi Aso Syuya Nagai Haruka Ono Masaoki Takagi 《Population Ecology》2021,63(3):204-218
Top predators are frequently the target of conservation programs. Owls are such predators. However, previous studies of owls are biased to species occurring in temperate regions, whereas most owl species occur in tropical or subtropical regions and are understudied. Furthermore, owls are often endemic to islands and of unknown conservation status. Demographic data for such species are especially scarce although they are essential for initiating and promoting their conservation. As a case study of demographic analysis of owls in a tropical or subtropical area and on islands, we applied an integrated population model to 7-year monitoring data (2012–2018) of the Ryukyu Scops Owl population on Minami-daito Island, Japan. We used survival history data from 903 individuals, reproduction and sex ratio data from 213 broods, and count data of 2,526 individuals in total. Long-term averages of annual survival rates were 0.73 for adult females and 0.74 for adult males, although the sexual difference was not significant. Sex ratio estimates fluctuated annually and long-term averages were slightly skewed to males: 0.51 among fledglings, 0.54 among yearlings, and 0.52 among adults. Long-term averages of population size were estimated to be 273.4 females and 296.8 males. The long-term average of population growth rate was 0.98, suggesting a slightly declining trend. It was fortunate to recognize the declining trend during the early phase. Considering the general lack of fundamental ecological data on owls of tropical or subtropical areas and on islands, it seems likely that many endangered owl populations await conservation efforts. 相似文献
104.
Tetsuro Mimura Mari Mimura Setsuko Washitani-Nemoto Somkid Siripatanadilok 《Journal of plant research》1997,110(1):31-36
Calluses initiated from leaves and seedlings of the mangrove,Bruguiera sexangula, were isolated from the original tissues and subcultured. Effects of NaCl on growth and ion content of each callus were measured.
The growth rate of calluses derived from leaves (leaf callus) gradually decreased as the NaCl concentration in the medium
increased, while that of calluses derived from seedlings (seedling callus) was highest in the medium containing 100 mM NaCl.
Concentrations of Na and Cl in both calluses increased with increasing the NaCl concentration in the culture medium. The concentration
of K of leaf calluses greatly decreased at 300 mM NaCl, while the K concentration of seedling calluses decreased only slightly
and remained relatively high even in the presence of 300 mM NaCl.
Transient treatment of leaf calluses with media containing high concentrations of NaCl frequently induced regeneration of
adventitious tissues. 相似文献
105.
Summary Lambda virC mutant, presumably an operator mutant for the operon including x, y, CII and O genes (Fig. 1), produce clearish plaque on a sensitive bacteria.Four revertants producing turbid plaques were isolated from virC and the mutational sites of which were studied. One (tw
1) is located very close to and on the left side of virC34, and another (tw
32) is at the almost same site of virC34. The others (tx
6 and tx
53) are located on the right side of virC34. tx recombinants have been isolated and characterized. These recombinants produce very turbid plaques and the rate of the repressor formation in the presence of CIts repressor is somewhat higher than that of wild type. tx develops very poorly after infection to sensitive cells but CItx develops normally. tx lysogens synthesize two to three times more exonuclease than the wild type lysogen. On a function of x region for the repressor formation and on a presence of a possible anti-repressor were discussed. The mutant tw
1 might be a promotor mutation of the CI-rex operon.This material has been published as an abstract in Jap. J. Genetics 45, 474 (1970). 相似文献
106.
107.
Yuka Tanaka Tomoko Inoue-Yokoo Kasem Kulkeaw Chiyo Yanagi-Mizuochi Senji Shirasawa Yoichi Nakanishi Daisuke Sugiyama 《PloS one》2015,10(9)
In mice, hematopoietic cells home to bone marrow from fetal liver prenatally. To elucidate mechanisms underlying homing, we performed immunohistochemistry with the hematopoietic cell marker c-Kit, and observed c-Kit(+) cells localized inside muscle surrounding bone after 14.5 days post coitum. Flow cytometric analysis showed that CD45(+) c-Kit(+) hematopoietic cells were more abundant in muscle than in bone marrow between 14.5 and 17.5 days post coitum, peaking at 16.5 days post coitum. CD45(+) c-Kit(+) cells in muscle at 16.5 days post coitum exhibited higher expression of Gata2, among several hematopoietic genes, than did fetal liver or bone marrow cells. Colony formation assays revealed that muscle hematopoietic cells possess hematopoietic progenitor activity. Furthermore, exo utero transplantation revealed that fetal liver hematopoietic progenitor cells home to muscle and then to BM. Our findings demonstrate that hematopoietic progenitor cell homing occurs earlier than previously reported and that hematopoietic progenitor cells reside in muscle tissue before bone marrow hematopoiesis occurs during mouse embryogenesis. 相似文献
108.
Nakanishi K Hoshino M Nakai M Kunimi Y 《Proceedings. Biological sciences / The Royal Society》2008,275(1640):1249-1254
Maternally inherited female-biased sex ratios have been documented in many invertebrate species. One cause of such biased sex ratios is male killing, i.e. only males die. In most species, male killing occurs during embryonic stages (early male killing) and is associated with cytoplasmic bacteria, including Wolbachia, Spiroplasma, Rickettsia, Flavobacteria and gamma proteobacteria. However, the oriental tea tortrix, Homona magnanima, is one of the few species in which male death occurs in the larval or pupal stage, and is thus an example of late male killing. We partially purified the agent causing late male killing in H. magnanima and showed that it consists of two RNA sequences. This represents an entirely novel agent causing late male killing. 相似文献
109.
Kishikawa M Sass JO Sakura N Nakanishi T Shimizu A Yoshioka M 《Biochimica et biophysica acta》2002,1588(2):135-138
Molybdenum cofactor deficiency is a fatal neurological disorder, which follows an autosomal-recessive trait and is characterized by combined deficiency of the enzyme, sulfite oxidase, xanthine dehydrogenase and aldehyde oxidase. Early detection of molybdenum cofactor-deficient patients is essential for their proper care and genetic counseling of families at risk. We demonstrate the use of S-sulfonated transthyretin (TTR) as a marker for molybdenum cofactor deficiency. Plasma or sera obtained from 4 patients with molybdenum cofactor deficiency and 57 controls were studied by electrospray ionization mass spectrometry (ESIMS) following selective enrichment of TTR by immunoprecipitation using protein G/A agarose. The data obtained from molybdenum cofactor deficiency samples indicated a strong increase in the peak height of S-sulfonated TTR. A more significant difference was revealed if the peak height ratio of S-sulfonated TTR and the sum of the other oxidized TTR were determined. By accurate determination of the ratio, the samples of molybdenum cofactor deficiency patients could clearly be distinguished from controls without molybdenum cofactor deficiency. 相似文献
110.
Yukio Kitade Masaharu Wakana Shin-ichi Terai Takayuki Tsuboi Masayuki Nakanishi Chizuko Yatome 《Nucleosides, nucleotides & nucleic acids》2013,32(12):2323-2333
Abstract 2-Bromoadenosine-substituted analogues of 2–5A, p5′A2′p-5′A2′p5′(br2A), p5′(br2A)2′p5′A2′p5′A, and p5′(br2A)2′p5′(br2A)2′p-S′(br2A), were prepared via a modification of a lead ion-catalyzed ligation reaction and were subsequently converted into the corresponding 5′-triphosphates. Both binding and activation of human recombinant RNase L by various 2-bromoadenosine-substituted 2–5A analogues were examined. Among the 2-bromoadenosine-substituted 2–5A analogues, the analogue with 2-bromoadenosine residing in the 2′-terminal position, p5′A2′p5′A2′p-5′(br2A), showed the strongest binding affinity and was as effective as 2–5A itself as an activator of RNase L. The CD spectrum of p5′A2′p-5′A2′p5′(br2A) was superimposable on that of p5′A2′p5′A2′p5′A, indicative of an anti orientation about the base-glycoside bonds as in naturally occurring 2–5A. 相似文献