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101.
Enumeration of transconjugated Ruminococcus albus and its survival in the goat rumen microcosm. 下载免费PDF全文
T Miyagi K Kaneichi R I Aminov Y Kobayashi K Sakka S Hoshino K Ohmiya 《Applied microbiology》1995,61(5):2030-2032
A transconjugant Ruminococcus albus A3 culture was released into a goat rumen, and the extent of its survival in the rumen microcosm was measured by distinguishing this bacterium from indigenous microbes by antibiotic resistance. A3 cells remained roughly constant for 14 days in this goat rumen. 相似文献
102.
Ikuo Takashima Maki Hiyoshi Hiroaki Kariwa Ryusuke Mukaiya Nobuo Hashimoto 《Microbiology and immunology》1996,40(4):265-270
Japanese quail were used for the infection model of avian chlamydiosis. One-day-old Japanese quail were highly susceptible to lethal infection by a Chlamydia psittaci strain of budgerigar origin upon inoculation via the air sac route with 104.1 FFU of the organism, showing an acute and lethal course with chlamydial propagation. In contrast, 7-day-old quail developed resistance to the infection as shown by the lack of lethal effect with the same dose. The resistance of 7-day-old birds was abolished by immunosuppressive treatment with cyclophosphamide. Upon inoculation with a sublethal dose of 102.1 FFU, latent infection was established in 1-day-old birds with a minimum number of the organism. The latent infection in the birds was converted to the lethal form by treatment with cyclophosphamide along with chlamydial propagation and suppression of antibody production. 相似文献
103.
Isamu Murakoshi Masanao Watanabe Tomoyo Okuda Eiji Kidoguchi Joju Haginiwa Shigeru Ohmiya Hirotaka Otomasu 《Phytochemistry》1985,24(11):2707-2708
(?)-Methyl 12-cytisineacetate (2) was isolated from methanol extracts of fresh flowers of Echinosophora koreensis together with seven known lupin alkaloids. Ethyl 12-cytisineacetate (3) was also isolated from ethanol extracts of the same flowers. Compounds 2 and 3 were artifacts and (?)-12-cytisineacetic acid (4) is assumed to be the principal source of 2 and 3. The variations in alkaloid content during growth of the flowers and the seedlings were also examined. 相似文献
104.
We propose a new concept of tumor progression monitoring using dual luciferases in living animals to reduce stress for small animals and the cost of luciferin. The secreted Cypridina luciferase (CLuc) was used as an ex vivo indicator to continuously monitor tumor progression. On the other hand, the non-secreted firefly luciferase was used as an in vivo indicator to analyze the spatial distribution of the tumor at suitable time points indicated by CLuc. Thus, the new monitoring systems that use dual luciferases are available, allowing long-term bioluminescence imaging under minimal stress for the experimental animals. 相似文献
105.
Yusuke Nakagawa Takeshi Muneta Koji Otabe Nobutake Ozeki Mitsuru Mizuno Mio Udo Ryusuke Saito Katsuaki Yanagisawa Shizuko Ichinose Hideyuki Koga Kunikazu Tsuji Ichiro Sekiya 《PloS one》2016,11(2)
Objective
Lubricin expression in the superficial cartilage will be a crucial factor in the success of cartilage regeneration. Mesenchymal stem cells (MSCs) are an attractive cell source and the use of aggregates of MSCs has some advantages in terms of chondrogenic potential and efficiency of cell adhesion. Lubricin expression in transplanted MSCs has not been fully elucidated so far. Our goals were to determine (1) whether cartilage pellets of human MSCs expressed lubricin in vitro chondrogenesis, (2) whether aggregates of human MSCs promoted lubricin expression, and (3) whether aggregates of MSCs expressed lubricin in the superficial cartilage after transplantation into osteochondral defects in rats.Methods
For in vitro analysis, human bone marrow (BM) MSCs were differentiated into cartilage by pellet culture, and also aggregated using the hanging drop technique. For an animal study, aggregates of BM MSCs derived from GFP transgenic rats were transplanted to the osteochondral defect in the trochlear groove of wild type rat knee joints. Lubricin expression was mainly evaluated in differentiated and regenerated cartilages.Results
In in vitro analysis, lubricin was detected in the superficial zone of the pellets and conditioned medium. mRNA expression of Proteoglycan4 (Prg4), which encodes lubricin, in pellets was significantly higher than that of undifferentiated MSCs. Aggregates showed different morphological features between the superficial and deep zone, and the Prg4 mRNA expression increased after aggregate formation. Lubricin was also found in the aggregate. In a rat study, articular cartilage regeneration was significantly better in the MSC group than in the control group as shown by macroscopical and histological analysis. The transmission electron microscope showed that morphology of the superficial cartilage in the MSC group was closer to that of the intact cartilage than in the control group. GFP positive cells remained in the repaired tissue and expressed lubricin in the superficial cartilage.Conclusion
Cartilage derived from MSCs expressed lubricin protein both in vitro and in vivo. Aggregation promoted lubricin expression of MSCs in vitro and transplantation of aggregates of MSCs regenerated cartilage including the superficial zone in a rat osteochondral defect model. Our results indicate that aggregated MSCs could be clinically relevant for therapeutic approaches to articular cartilage regeneration with an appropriate superficial zone in the future. 相似文献106.
107.
Purification and Properties of Intracellular Proteinase from Streptococcus cremoris 总被引:4,自引:4,他引:0 下载免费PDF全文
Proteolytic activity in the extract from the cells of Streptococcus cremoris increased in the presence of casein, lactose, glucose, and CaCl2 in the media but was negligibly detectable in the extract of the cells harvested from the culture containing succinate or citrate. The intracellular proteinase from S. cremoris harvested from tomato medium was purified 150-fold in this experiment. The enzyme had a molecular weight of 140,000, optimum pH at 6.5 to 7.0, and maximum activity at 30 C. The proteinase was activated by Ca2+ and inhibited by Zn2+, Cu2+, Hg2+, Fe2+, ethylenediaminetetraacetate, and sodium lauryl sulfate. The Km value of the enzyme towards each casein fraction was almost the same, and the Vmax of the enzyme towards αs-casein was smaller than those towards the other casein fractions. 相似文献
108.
Yamaguchi Isomaro; Nakagawa Ryusuke; Kurogochi Shin; Murofushi Noboru; Takahashi Nobutaka; Weiler Elmar W. 《Plant & cell physiology》1987,28(5):815-824
Polyclonal anti-GA5-antiseruin and anti-GA20-antiserum wereprepared by immunizing rabbits with conjugates of N-GA5-ß-alanylBSA and N-GA20-ß-alanyl BSA. By radioimmunoassay usingthese antisera, GA5 and GA20 in developing fruits of Pharbitisnil Chois were analyzed after several purification steps andthe results were compared with those obtained by GC-MS to examinethe reliability of the analysis by radioimmunoassay. The analyticalresults by radioimmunoassay did not agree with those by GC-MSuntil two-step purifications by HPLC, indicating that samplesmust be suitably purified prior to radioimmunoassay to obtainreliable results. (Received November 13, 1986; Accepted April 17, 1987) 相似文献
109.
Pumpkin seed globulin is composed of heterogeneous polypeptidechains, acidic and chains and basic 1 and 2 chains (12). This study showed that the basicchains had similar N-terminal sequences, Gly-Leu-Asp-Glu-Thr-Ile-for the 1 chain and Gly-Leu-Glu-Glu-Thr-Ile- for 2. On the contrary,the N-terminal sequences of the acidic and chains were dissimilar, Ile-Gln-Gly-Tyr- for the chain and no N-terminal residue for the chain, according to routine terminal analysis. Pyrrolidonylpeptidase digestion of the chain and its thermolysin digestion followed by Edman degradationsrevealed that the N-terminal sequence of the chain was < Glu-Ile-Glu-Gln-Gln-Glu-Pro(Trp,Ser)-. The N-terminal sequences and the C-terminal residuesindicated that the acidic and chains were more heterogeneous than the basic 1 and 2 chains.A preliminary study on the degradation of storage globulin isalso presented. (Received November 9, 1979; ) 相似文献
110.
Ishihara Ryo Matsumura Kentarou Jones Jordan Elouise Yuhao Ji Fujisawa Ryusuke Nagaya Naohisa Miyatake Takahisa 《Journal of Ethology》2021,39(1):107-113
Journal of Ethology - Death feigning (or tonic immobility) is an effective antipredator strategy. However, prolonged immobility on the ground increases the risk of being parasitized or eaten by... 相似文献