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391.
Hiroyuki Fujimori Masako Kiyono Kazunori Nobuhara Hidemitsu Pan-Hou 《FEMS microbiology letters》1996,135(2-3):317-321
Abstract To study the physiological role of the red pigments in soil strain Pseudomonas K-62, we isolated a red pigment-deficient white mutant from the soil strain by treatment with mitomycin C and compared the phenotypic properties of the mutant and parent strain. The red pigments, which were classified as one of carotenoids based on their physicochemical properties, were separated into two groups, designated pigment A and B respectively on NH-Chromatorex HPLC.The crude pigments and pigment B which could react with Hg2+ in the wild-type Pseudomonas K-62 and its mercury-resistant plasmid-deficient strain were enhanced by the addition of Hg2+ . The white mutant thus obtained showed a greater sensitivity to Hg2+ than the wild-type reddish strain despite containing the resistant plasmids. The major component in pigment B was identified by mass spectrometric analysis as 1-hydroxy-1-methoxy-1,2, 1',2',7',8'-hexahydro-ψ,ψ-caroten-4-one, a carotenoid monoketone. These results suggested that red pigments, especially pigment B, may account, at least partially, for defense against Hg2+ in the bacterial environments. 相似文献
392.
S Namiki F Kaneda M Ikegami T Arai K Fujimori S Asada H Hama Y Kasuya K Goto 《Bioorganic & medicinal chemistry》1999,7(8):1695-1702
Three new caged nitric oxides (NOs)-BNN3, BNN5Na, and BNN5M were tested for biological use. BNNs have a strong ultraviolet (UV) absorption band (lambda(max): 300 nm, epsilon: 13.5 mM(-1) cm (-1)) extended to 420 nm and produce NO upon irradiation with 300-360 nm light in quantum yields about 2. A photoexcited BNN molecule yields two NOs with time constants of less than 10 ns for phase 1 and less than 20 micros for phase 2 at 37 degrees C, suggesting usefulness of BNNs for measuring in vivo and in vitro fast NO reactions. Upon irradiating with UV light, caged nitric oxides-loaded rat aortic strips maintained in a state of active tonic contraction effectively relaxed ( < 3 microM BNN5M loading solution concentration). BNN3 is incorporated in the lipid membrane. BNN5Na, insoluble in organic solvents but water soluble, localizes in the water phase. BNN5M, is muscle-cell-permeable and hydrolysed to BNN5Na to remain in cytosol. BNNs were thermally stable and demonstrated no observable toxicity. 相似文献
393.
Urata H Fujimori M Aono C Yamakawa T Harada E Akagi M 《Nucleosides, nucleotides & nucleic acids》2008,27(4):421-430
Clay is a possible candidate for an effective catalyst in prebiotic chemical evolution of biomolecules. Montmorillonite was reported to effectively catalyze oligomerization of racemic adenosine 5'-phosphorimidazolide (DL-ImpA). In the oligomerization reaction, considerable amounts of cyclic dimers as well as linear dimers were produced in the oligomerization reactions. To assess the regio- and diastereo-selectivities of the oligomerization reaction, the dimer products including cyclic dimers were completely identified by means of enzymatic degradation reactions of the products. 相似文献
394.
Isolation and expression profiling of genes upregulated in bone marrow-derived mononuclear cells of rheumatoid arthritis patients. 总被引:1,自引:0,他引:1
395.
In this study, we found that Krüppel-like factor (KLF) 9 activate the progression of the early phase of adipocyte differentiation in mouse adipocytic 3T3-L1 cells. KLF9 mRNA was detected in preadipocytes; and its level increased after the initiation of adipocyte differentiation, reached its maximum at 1 h, and gradually decreased thereafter. Functional suppression of KLF9 mRNA by its siRNAs repressed the accumulation of the intracellular lipids with a reduction in the expression of CCAAT/enhancer-binding protein (C/EBP) β, but not in that of C/EBPδ. In contrast, C/EBPβ and C/EBPδ did not affect the expression of KLF9 in 3T3-L1 cells. A chromatin immunoprecipitation assay revealed that KLF9 bound the KLF binding element at position − 874 of the mouse C/EBPβ promoter. Moreover, the ability of KLF9 to bind to this element was enhanced, with a peak at 1–2 h after the initiation of adipogenesis, whose profile well resembled that of the expression of the C/EBPβ gene in 3T3-L1 cells. These results indicate that KLF9 activated the early phase of adipogenesis by enhancing the expression of the C/EBPβ gene in 3T3-L1 cells. 相似文献
396.
Michito Shimozuru Mina Jimbo Keisuke Adachi Kei Kawamura Yuri Shirane Yoshihiro Umemura Tsuyoshi Ishinazaka Masanao Nakanishi Mayu Kiyonari Masami Yamanaka Yukihiro Amagai Ayaho Ijuin Tomoki Sakiyama Shinsuke Kasai Takane Nose Masataka Shirayanagi Hifumi Tsuruga Tsutomu Mano Toshio Tsubota Keita Fukasawa Hiroyuki Uno 《Ecology and evolution》2022,12(9)
Robust estimates of demographic parameters are critical for effective wildlife conservation and management but are difficult to obtain for elusive species. We estimated the breeding and adult population sizes, as well as the minimum population size, in a high‐density brown bear population on the Shiretoko Peninsula, in Hokkaido, Japan, using DNA‐based pedigree reconstruction. A total of 1288 individuals, collected in and around the Shiretoko Peninsula between 1998 and 2020, were genotyped at 21 microsatellite loci. Among them, 499 individuals were identified by intensive genetic sampling conducted in two consecutive years (2019 and 2020) mainly by noninvasive methods (e.g., hair and fecal DNA). Among them, both parents were assigned for 330 bears, and either maternity or paternity was assigned to 47 and 76 individuals, respectively. The subsequent pedigree reconstruction indicated a range of breeding and adult (≥4 years old) population sizes: 128–173 for female breeders and 66–91 male breeders, and 155–200 for female adults and 84–109 male adults. The minimum population size was estimated to be 449 (252 females and 197 males) in 2019. Long‐term continuous genetic sampling prior to a short‐term intensive survey would enable parentage to be identified in a population with a high probability, thus enabling reliable estimates of breeding population size for elusive species. 相似文献
397.
Yoshikazu Takagi Takane Fujimori Hajime Kaneko Kunio Kato 《Bioscience, biotechnology, and biochemistry》2013,77(3):769-770
Optical isomers of methyl jasmonate were resolved from a commercial mixture via the formation of bornyl jasmonate diastereoisomers. The symmetry and magnitude of the optical rotation spectra, and the observation that only one isomer, (+)-methyl epijasmonate had the characteristic methyl jasmonate odor indicated that these preparations were optically pure. 相似文献
398.
N. Ogata S. Fujimori Y. Oka K. Kaneko 《Nucleosides, nucleotides & nucleic acids》2013,32(4-6):321-324
We have retrospectively investigated the effects of three strong statins, atorvastatin, pitavastatin, and rosuvastatin, on serum uric acid (SUA) levels. SUA levels after a few months of statin treatment were compared with those before treatment in 150 outpatients with dyslipidemia. In the atorvastatin (n = 62) and rosuvastatin (n = 45) groups, the SUA levels were reduced by 6.5% (p < 0.0001) and 3.6% (p = 0.03) respectively, but in the pitavastatin group (n = 43), the SUA level increased by 3.7% (p = 0.38). Because uric acid is considered a risk factor for cardiovascular disorders, atorvastatin or rosuvastatin treatment may be recommended when statins are used in patients at high risk for cardiovascular disorders complicated with hyperuricemia. 相似文献
399.
400.
Production of Pacific oyster Crassostrea gigas in Miyagi and Hiroshima (Japan) has gradually increased, with a marked increase in imported oysters from Goseong (Korea),
and then cultured oysters of the Miyagi, Hiroshima, and Goseong populations accounting for most oyster consumption in Japan.
In this study, we developed a simple PCR-RFLP analysis of a mitochondrial DNA noncoding region (mtDNA-NCR) for differentiating
cultured oysters of these populations. PCR amplification yielded a 818 bp fragment comprising the entire mtDNA-NCR and parts
of adjacent tRNACys and tRNAAsn genes from all the specimens. By use of a wide restriction test using 30 different restriction enzymes, only a single enzyme
only, AluI, produced a unique RFLP pattern enabling us to discriminate Miyagi and Hiroshima oysters from Goseong oysters. This difference
is probably because of nucleotide alteration at the presumptive AluI recognizing site on position 439 of the mtDNA-NCR. Our simple, robust and cost-effective PCR-RFLP analysis is potentially
useful for population genetic investigation of cultured Pacific oyster, particularly when large numbers of specimens must
be analyzed. 相似文献