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161.
Shinobu Sato Masanori Kanazawa Kosuke Mukumoto Michinori Waki 《Analytical biochemistry》2008,381(2):233-239
A thiolated oligonucleotide having three ferrocenes was immobilized on a gold electrode through the sulfur-gold linkage. This electrode showed a current response based on the redox reaction of the ferrocene moieties and this response was decreased after treatment with deoxyribonuclease I (DNase I), suggesting the disappearance of the ferrocene moieties on the electrode by the DNase I digestion. A linear correlation between i0 and i, which are current peaks before and after DNase I treatment, respectively, was observed and this slope was decreased with increase in the amount of DNase I. No current decrease was observed in the presence of EDTA or RNase A instead of DNase I. These results suggested that the current decrease responded specifically to the amount of DNase I and this electrode could be used for an electrochemical DNase I assay. Under the optimum conditions of DNase I digestion at 37 °C for 30 min, a quantitative analysis could be achieved in the range of 10−4-10−2 units/μl of DNase I. 相似文献
162.
Oikawa K Yoshida K Takanashi M Tanabe H Kiyuna T Ogura M Saito A Umezawa A Kuroda M 《Biochemical and biophysical research communications》2008,374(2):361-364
Each chromosome occupies its own-specific space called a ‘territory’ within the interphase nucleus, and the arrangement of chromosome territories (CTs) is important in epigenetic mechanisms. The molecular mechanism to determine the positioning of CTs, however, remains unknown. On the other hand, dioxin is known to be the typical environmental pollutant that affects a wide variety of biological events in many species. Here, we show that dioxin enlarges the minimum distance between chromosome 12 and chromosome 16 territories in human preadipocyte cells, and the alteration of chromosome positioning is canceled by an aryl hydrocarbon receptor (AhR) antagonist α-naphthoflavone. Thus, AhR may be a key molecule to regulate chromosome positioning. Our results suggest a novel effect of dioxin toxicity, and demonstrate a clue to reveal the novel molecular mechanism for the arrangement of CTs. 相似文献
163.
The effect of house building design and environment on the fungal movement in the houses of 41 bronchial asthma (BA) patients
has been investigated by examining house dust. The presence and composition of fungi were determined and compared in relation
to building structure, house age, size of living room, main flooring material, presence of a living-room rug or air purifier,
and frequency of vacuum cleaning. Among these elements, fungal CFU apparently varied only between building structure: wooden-board
houses had significantly higher numbers of fungi than reinforced concrete houses (p < 0.01), and wooden mortar or iron-framed
prefabricated houses had significantly higher numbers of fungi than reinforced concrete houses (p < 0.05). Classification
of the types of fungi present in the house dust of BA patients showed that, regardless of the building designs, there were
high levels of osmophilic fungi (group A) and fungi that survive at relatively dry conditions (group B), whereas fungi that
survive in very wet conditions (group D) were present at low frequency.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
164.
Jong-Chul Park Min Sub Lee Dong Hee Lee Bong Joo Park Dong-Wook Han Masakazu Uzawa Kosuke Takatori 《Applied microbiology》2003,69(4):2405-2408
Seawater used in mariculture has been suspected of being a potential source of infection. In this study, the lethal effects of low-amperage electric treatment on microorganisms were examined in natural seawater and in seawater inoculated with Vibrio parahaemolyticus. In both cases, bacteria including V. parahaemolyticus in seawater were completely eliminated in 100 ms by a 0.5-A, 12-V direct current. Electron microscopic investigation of the electrically treated bacteria revealed substantial structural damage at the cellular level. In conclusion, our results indicate that low-amperage electric treatment is effective for rapid inactivation of microorganisms in seawater. 相似文献
165.
Koichi Takahashi Kosuke Homma Valentina P. Vetrova Sergey Florenzev Toshihiko Hara 《植被学杂志》2001,12(5):627-634
Abstract. A 1‐ha plot was established in a Betula platyphylla‐Picea ajanensis mixed boreal forest in the central Kamchatka peninsula in Russia to investigate stand structure and regeneration. This forest was relatively sparse; total density and stand basal area were 1071/ha and 25.8 m2/ha, respectively, for trees > 2.0 cm in trunk diameter at breast height (DBH). 25% of Betula regenerated by sprouting, and its frequency distribution of DBH had a reverse J‐shaped pattern. In contrast, Picea had a bimodal distribution. The growth rates of both species were high, reaching 20 m in ca. 120 yr. The two species had clumped distributions, especially for saplings. Betula saplings were not distributed in canopy gaps. Small Picea saplings were distributed irrespective of the presence/absence of gaps, while larger saplings aggregated in gaps. At the examined spatial scales (6.25–400 m2) the spatial distribution of Betula saplings was positively correlated with living Betula canopy trees and negatively with dead Picea canopy trees. This suggests that Betula saplings regenerated under the crowns of Betula canopy trees and did not invade the gaps created by Picea canopy trees. The spatial distribution of Picea saplings was negatively correlated with living and dead Betula canopy trees and positively with dead Picea canopy trees. Most small Picea seedlings were distributed under the crowns of Picea trees but not under the crowns of Betula trees or in gaps. This suggests that Picea seedlings establish under the crowns of Picea canopy trees and can grow to large sizes after the death of overhead Picea canopy trees. Evidence of competitive exclusion between the two species was not found. At a 20 m × 20 m scale both skewness and the coefficient of variation of DBH frequency distribution of Picea decreased with an increase in total basal area of Picea while those of Betula were unchanged irrespective of the increase in total basal area of Betula. This indicates that the size structure of Picea is more variable with stand development than that of Betula on a small scale. This study suggests that Betula regenerates continuously by sprouting and Picea regenerates discontinuously after gap formation and that the species do not exclude each other. 相似文献
166.
Structure of human holocarboxylase synthetase gene and mutation spectrum of holocarboxylase synthetase deficiency 总被引:4,自引:0,他引:4
Xue Yang Yoko Aoki Xue Li Osamu Sakamoto Masahiro Hiratsuka Shigeo Kure Sepidh Taheri Ernst Christensen Koji Inui Mitsuru Kubota Miki Ohira Misao Ohki Jun Kudoh Kazuhiko Kawasaki Kazunori Shibuya Ai Shintani Shuichi Asakawa Shinsei Minoshima Nobuyoshi Shimizu Kuniaki Narisawa Yoichi Matsubara Yoichi Suzuki 《Human genetics》2001,109(5):526-534
Holocarboxylase synthetase (HLCS) is an enzyme that catalyzes the incorporation of biotin into apo-carboxylases, and its deficiency causes biotin-responsive multiple carboxylase deficiency. The reported sequences of cDNA for human HLCS from liver, lymphocyte, and KG-1 myeloid cell lines differ at their 5' regions. To elucidate variations of the human HLCS mRNA and longer 5' cDNA ends, we performed screening of the human liver cDNA library and rapid amplification of the cDNA ends (RACE). Our results suggest the existence of three types of HLCS mRNA that start at different exons. The first type starts at exon 1, and the second type starts at exon 3, and both are found in various human tissues. The third type, corresponding to the cDNA from the KG-1 cell, starts at exon 2 of the HLCS gene. Various splicing patterns from exons 3-6 were also observed. None of the variations of cDNA found created a new initiation codon. Mutation screening from exons 6-14, therefore, was sufficient to detect amino acid changes in HLCS in patients. Our direct sequencing strategy for screening mutations in the HLCS gene revealed mutations in five Japanese patients and seven non-Japanese patients. Our analyses involving 12 Japanese and 13 non-Japanese patients and studies by others indicate that (1) there is no panethnically prevalent mutation; (2) the Arg508Trp, Gly581Ser, and Val550Met mutations are found in both Japanese and non-Japanese populations; (3) the IVS10+5G-->A mutation is predominant and probably a founder mutation in European patients; (4) the 655-656insA, Leu237Pro, and 780delG mutations are unique in Japanese patients; (5) the spectrum of the mutations in the HLCS gene may vary substantially among different ethnic groups. 相似文献
167.
Koya Yamashiro Daisuke Sato Hideaki Onishi Kazuhiro Sugawara Sho Nakazawa Hirofumi Shimojo Kosuke Akatsuka Hiroki Nakata Atsuo Maruyama 《PloS one》2015,10(11)
Athletic training is known to induce neuroplastic alterations in specific somatosensory circuits, which are reflected by changes in somatosensory evoked potentials and event-related potentials. The aim of this study was to clarify whether specific athletic training also affects somatosensory Nogo potentials related to the inhibition of movements. The Nogo potentials were recorded at nine cortical electrode positions (Fz, Cz, Pz, F3, F4, C3, C4, P3 and P4) in 12 baseball players (baseball group) and in 12 athletes in sports, such as track and field events and swimming, that do not require response inhibition, such as batting for training or performance (sports group). The Nogo potentials and Go/Nogo reaction times (Go/Nogo RTs) were measured under a somatosensory Go/Nogo paradigm in which subjects were instructed to rapidly push a button in response to stimulus presentation. The Nogo potentials were obtained by subtracting the Go trial from the Nogo trial. The peak Nogo-N2 was significantly shorter in the baseball group than that in the sports group. In addition, the amplitude of Nogo-N2 in the frontal area was significantly larger in the baseball group than that in the sports group. There was a significant positive correlation between the latency of Nogo-N2 and Go/Nogo RT. Moreover, there were significant correlations between the Go/Nogo RT and both the amplitude of Nogo-N2 and Nogo-P3 (i.e., amplitude of the Nogo-potentials increases with shorter RT). Specific athletic training regimens may induce neuroplastic alterations in sensorimotor inhibitory processes. 相似文献
168.
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170.
It was demonstrated that a 67 kilodalton (kDa) protein of Mycoplasma pneumoniae is a main cross-reactive antigen with similar molecular weight protein of Mycoplasma genitalium by Western blot analysis using monoclonal antibody to 67 kDa protein of M. pneumoniae and hyperimmune rabbit sera directed against each mycoplasma strain. 相似文献