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371.
Imamura Machiko; Tsuzuki Mikio; Shiraiwa Yoshihiro; Miyachi Shigetoh 《Plant & cell physiology》1983,24(3):533-540
The effect of carbonic anhydrase (CA) on time courses of photosynthetic14C incorporation in the presence of 14CO2 or NaH14CO3 was studiedwith cells of Chlamydomonas reinhardtii which had been grownunder ordinary air (low-CO2 cells) or air enriched with 4% CO2(high-CO2 cells). Experimental data obtained at 20°C andpH 8.0 suggested that the major form of inorganic carbon utilizedby high-CO2 cells was CO2, while that utilized by low-CO2 cellswas HCO3. The cell suspension showed CA activity which was comparableto that observed in the sonicate of cells. Both activities werehigher in low-CO2 cells than in high-CO2 cells. The mechanism by which HCO3 is utilized by low-CO2 cellsof C. reinhardtii is discussed.
3Present address: Department of Biology, Faculty of Science,University of Niigata, Niigata 950-21, Japan. (Received August 4, 1982; Accepted January 19, 1983) 相似文献
372.
Eliana Badiale Furlong Lucia Maria Valente Soares Celia Campos Lasca Elizabeth Yoko Kohara 《Mycopathologia》1995,131(3):185-190
Wheat from two cultivars with contrasting characteristics were harvested in ten experimental plots located in wheat producing areas of the State of São Paulo, Brazil. The samples (10 of each cultivar) were analyzed by a gaschromatographic method for deoxynivalenol (DON), nivalenol (NIV), diacetoxyscirpenol (DAS), toxins T-2 (T-2) and HT-2, T-2 tetraol, T-2 triol, and by a thin-layer chromatographic method for zearalenone (ZEN), aflatoxins B1, B2, G1, G2, ochratoxin A and sterigmatocystin. No mycotoxins were detected in 13 samples. DON was found in four samples (0.47–0.59 µg/g), NIV in three samples (0.16–0.40 µg/g), T-2 in two samples (0.40, 0.80 µg/g), DAS in one sample (0.60 µg/g), and ZEN in three samples (0.04–0.21 µg/g). The wheat samples were also examined for the incidence of fungi.Alternaria, Drechslera, Epicoccum andCladosporium were the prevailing genera. Among theFusarium spp.,F. semitectum was present in 19 samples andF. moniliforme in 18 samples. NoF. graminearum was isolated in the samples.Abbreviations DAS
diacetoxyscirpenol
- DON
deoxynivalenol
- NIV
nivalenol
- T-2
T-2 toxin
- ZEN
zearalenone 相似文献
373.
Takakazu Kaneko Yasukazu Nakamura Shigemi Sasamoto Akiko Watanabe Mitsuyo Kohara Midori Matsumoto Sayaka Shimpo Manabu Yamada Satoshi Tabata 《DNA research》2003,10(5):221-228
The genome of the unicellular cyanobacterium Synechocystis sp. PCC 6803 consists of a single chromosome and several plasmids of different sizes, and the nucleotide sequences of the chromosome and three small plasmids (5.2 kb, 2.4 kb, and 2.3 kb) have already been sequenced. We newly determined the nucleotide sequences of four large plasmids, which have been identified in our laboratory (pSYSM:120 kb, pSYSX:106 kb, pSYSA:103 kb, and pSYSG:44 kb). Computer-aided analysis was performed to explore the genetic information carried by these plasmids. A total of 397 potential protein-encoding genes were predicted, but little information was obtained about the functional relationship of plasmids to host cell, as a large portion of the predicted genes (77%) were of unknown function. The occurrence of the potential genes on plasmids was divergent, and parA was the only gene common to all four large plasmids. The distribution data of a Cyanobacterium-specific sequence (HIP1: 5'-GCGATCGC-3') suggested that respective plasmids could have originated from different cyanobacterial strains. 相似文献
374.
375.
376.
Mashiba T Udaka K Hirachi Y Hiasa Y Miyakawa T Satta Y Osoda T Kataoka S Kohara M Onji M 《Immunogenetics》2007,59(3):197-209
Developing a peptide-based vaccine for the highly variable hepatitis C virus (HCV) remains a challenging task. Variant viruses
not only escape antigen presentation but also persist in a patient as quasi-species. Such variants are often antagonistic
to the responding T cell repertoire. To overcome these problems, we herein propose a cocktail vaccine consisting of a few
epitope peptides, which make it possible to outpace the emergence of variant viruses. To design such a vaccine, we developed
a way to identify HLA-A*2402-binding peptides efficiently by means of the computational scanning of the whole genome of the
pathogen. Most of the predicted peptides exhibited strong binding to the HLA-A*2402 molecule, while also inducing CD8 T cell
responses from the patients’ peripheral blood mononuclear cells (PBMCs). Peptide-induced T cells were capable of lysing HCV-expressing
HepG2 cells which process antigens endogenously. The amount of HCV core antigen in the patients’ livers suggested that the
lytic activity of the peptide-induced T cells was clearly in a range suitable for therapeutic use. If T cells were activated
under optimal conditions by high density peptides, then they tended to be relatively tolerant of single amino acid variations
for cytolysis. Finally, an analysis of the viral population isolated in Japan suggested no obvious changes due to immune evasion
in the viral genome even in a host population highly biased toward HLA-A*2402.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
377.
Alkaline phosphatase (ALP) activity was detected in the restricted mesenchymal and epithelial regions in mouse vibrissal follicles. Its localization and strength dramatically changed during the hair cycle. Activity in the dermal papilla (DP) was moderate in very early anagen, reached a maximal level in early anagen, decreased at the proximal region of DP after mid anagen, and was kept at a low level during catagen. The bulbar dermal sheath showed intense ALP activity only in early anagen. Although most bulbar epithelium did not show ALP activity, germinative epidermal cells that were adjacent to the ALP-negative DP cells became ALP-positive in mid anagen and rearranged in a single layer so as to encapsulate the DP in mid catagen. During catagen, the outermost layer of bulbar epithelium became ALP-positive, which could be follicular epithelial precursors migrating from the bulge. Before the initiation of hair formation, ALP activity in the bulbar epithelium rapidly decreased and that in DP increased. These dynamic changes of ALP expression might be related to DP's functions in hair induction and also to reconstruction of the bulbar structure during the hair cycle. 相似文献
378.
Kozue Uchio-Yamada Fumio Kasai Midori Ozawa Arihiro Kohara 《In vitro cellular & developmental biology. Animal》2017,53(3):225-230
Misidentification or cross-contamination of cell lines can cause serious issues. Human cell lines have been authenticated by short tandem repeat profiling; however, mouse cell lines have not been adequately assessed. In this study, mouse cell lines registered with the JCRB cell bank were examined by simple sequence length polymorphism (SSLP) analysis to identify their strains. Based on comparisons with 7 major inbred strains, our results revealed their strains in 80 of 90 cell lines. However, 12 of the 80 cell lines (15%) were found to differ from registered information. Of them, 4 cell lines originated from the same mouse, which had been generated through mating between two different inbred strains. The genotype of the mouse sample had not been examined after the backcross, leading to strain misidentification in those cell lines. Although 8 other cell lines had been established as sublines of a BALB/c cell line, their SSLP profiles are similar to a Swiss cell line. This affects differences in genotypes between inbred and outbred strains. Because the use of inbred samples and interbreeding between strains are not involved in human materials, our results suggest that the cause and influence of misidentification in mouse cell lines are different from those in human. 相似文献
379.
Xestoleberis hanaii Ishizaki, 1968 is one of the most abundant species on the Japanese coast and can be collected in all seasons from intertidal calcareous algae on rocky shores. Several characteristics make this species a suitable `experimental animal' in the laboratory: (1) adaptability to artificial environments (room temperature, petri dish, artificial seawater, single cultured food-type), (2) high fertility (active copulatory behaviour, egg brooding within the carapace, high egg productivity) and (3) rapid growth rate. Females mate after the final moult (when the reach sexual maturity); oviposition of fertilized eggs takes place over a period of four days after the final moult. Eggs (about 40 in total) are laid a few at a time in the postero-dorsal brood space of the carapace; they hatch in about 9 d as A-7 instars which are then discharged from the brood space within a day or two. Seven moults take place within the next approx. 33 (female) or 39 (male) days to reach adulthood. Adult females live for about 18 weeks and may repeat the reproductive cycle three times; adult males live for about 14 weeks. 相似文献
380.
Shigeo Tsujimura Hajime Tsukada Hiroyuki Nakahara Takuo Nakajima Machiko Nishino 《Hydrobiologia》2000,434(1-3):183-192
Seasonal variations of colony numbers of Microcystis aeruginosa(Kütz.) Kütz. and M. wesenbergii(Komárek) Komárek in N. V. Kondrat. in sediments of Lake Biwa were investigated over a period of 1 year. At two stations located in the shallow South Basin of Lake Biwa (ca. 4 m water depth), the colony number of Microcystisfluctuated seasonally. The number had a tendency to gradually decrease from winter to early summer, while it increased through mid-summer and autumn. Since the Microcystispopulation in sediment was rather small, intensive growth and accumulation in the water column should be important for the formation of Microcystisblooms in Lake Biwa. Microcystiscolonies in the sediment samples after June were observed to be floating in a counting chamber under a microscope. The observation suggests that the recruitment of Microcystis colonies into the water column mostly occurs in early summer. The number of Microcystiscolonies in the deep North Basin of Lake Biwa (70 – 90 m water depth) was larger than in the South Basin. Because the seasonal variation of colony numbers was not observed in the North Basin, and Microcystiscells do not have gas vesicles, these colonies will not return into the water column. The colonies isolated from the sediment of the North Basin were able to grow in cultured conditions, in the same way as those from the sediment of the South Basin. Therefore, Microcystiscolonies may survive for a long time under stable conditions of low temperature (ca. 8 °C) and darkness, in the sediment of the deep North Basin, accumulating gradually each year. 相似文献