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981.
T Kusakabe Y Sugimoto T Maeda Y Nakajima M Miyano J Nishikawa S Tone Y Kawaguchi K Koga T Ohyama 《Gene》2001,274(1-2):271-281
A bent DNA library was constructed from human genomic DNA, from which a new clone belonging to the human LINE-1 sequence family was isolated and characterized. This clone, with a length of 378 base pairs and termed HBC-1 (human bent clone-1), contained an intrinsically occurring curved DNA structure. By permutation analysis, the center of curvature of this fragment was mapped onto the nucleotide position 886 from the 5' terminus of the complete LINE-1 sequence. Reporter plasmids, which contain HBC-1, were effectively integrated into human chromosome, indicating that the bent DNA structure provides a preferential donor site for the integration of human LINE-1 sequences. The present finding may provide an explanation as to why some inactivated LINE-1 sequences on human chromosomes carry the deletion at their 5' termini. 相似文献
982.
Functional Significance of the Preconditioning-induced
Down-regulation of Glutamate Transporter GLT-1 in Neuron/astrocyte Co-cultures 总被引:2,自引:0,他引:2
In the brain, prior sublethal ischemia (preconditioning, PC) is known to produce tolerance of neurons to subsequent lethal
ischemia. This study aims at elucidating what alterations were induced in neurons and/or astrocytes by PC treatment. The rise
in the extracellular concentration of glutamate during ischemia was markedly suppressed by the prior PC treatment. Immunocytochemical
and Western blot analyses demonstrated that the expression of the astrocytic glutamate transporter GLT-1 was transiently down-regulated
after the PC insult. The PC insult possibly suppressed the neuron-derived factors up-regulating GLT-1. Here we show that PC-induced
down-regulation of GLT-1 is crucial for the increased neuronal resistance to subsequent severe ischemic insult. 相似文献
983.
984.
Emergence of nuclear heparanase induces differentiation of human mammary cancer cells 总被引:3,自引:0,他引:3
Nobuhisa T Naomoto Y Takaoka M Tabuchi Y Ookawa K Kitamoto D Gunduz E Gunduz M Nagatsuka H Haisa M Matsuoka J Nakajima M Tanaka N 《Biochemical and biophysical research communications》2005,331(1):175-180
The study of epithelial differentiation touches upon many modern aspects of biology. The epithelium is in constant dialogue with the underlying mesenchyme to control stem cell activity, proliferation in transit-amplifying compartments, lineage commitment, terminal differentiation and, ultimately, cell death. There are spatially distinct compartments dedicated to each of these events. Recently we reported that heparanase is expressed in nucleus as well as in the cytoplasm and that nuclear heparanase seems to be related to cell differentiation. In this study, we investigated the role of nuclear heparanase in differentiation by transducing human mammary epithelial cancer cells with heparanase which was delivered specifically into nucleus. We observed that expression of nuclear heparanase allowed the cells to differentiate with the appearance of lipid droplets. This finding supports the idea that heparanase plays a novel role in epithelial cell differentiation apart from its known enzymatic function. 相似文献
985.
Nakajima K Nonaka K Yamamoto K Yamaguchi N Tani K Nasu M 《Letters in applied microbiology》2005,40(2):128-132
AIMS: To apply fluorescent staining method for fast assessment of microbial quality of herbal medicines. METHODS AND RESULTS: The number of total bacteria and esterase-active bacteria on powdered traditional Chinese medicines were enumerated by fluorescent staining method using 6-carboxyfluorescein diacetate (6CFDA) and 4',6-diamidino-2-phenylindole (DAPI), and they were compared with colony-forming units (CFU). The CFU was approximately 10(3) per gram in ginseng radix, and no bacterial colonies were detected from others. However, the total bacterial number (TDC) was more than 10(7) per gram, and number of bacteria possessing esterase activity ranged from 1 to 3% of TDC. CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY: Many bacteria in each Chinese medicine had enzyme activity and most of them could not be detected by conventional plate counting technique. Enumeration of bacterial cells on traditional Chinese medicines by fluorescent staining method requires less than 1 h. The double staining method with 6CFDA and DAPI could be applicable to rapid microbial monitoring of crude drugs. 相似文献
986.
Infertility with defective spermiogenesis in mice lacking AF5q31, the target of chromosomal translocation in human infant leukemia 下载免费PDF全文
987.
Ueda K Nakajima Y Akahane-Yamada R 《Journal of PHYSIOLOGICAL ANTHROPOLOGY and Applied Human Science》2005,24(1):129-133
Our auditory system has to organize and to pick up a target sound with many components, sometimes rejecting irrelevant sound components, but sometimes forming multiple streams including the target stream. This situation is well described with the concept of auditory scene analysis. Research on speech perception in noise is closely related to auditory scene analysis. This paper briefly reviews the concept of auditory scene analysis and previous and ongoing research on speech perception in noise, and discusses the future direction of research. Further experimental investigations are needed to understand our perceptual mechanisms better. 相似文献
988.
Nanatani K Ohonishi F Yoneyama H Nakajima T Abe K 《Biochemical and biophysical research communications》2005,328(1):20-26
AspT is an electrogenic aspartate:alanine exchange protein that represents the vectorial component of a proton-motive metabolic cycle found in some strains of Tetragenococcus halophilus. AspT is the sole member of a new family, the Aspartate: Alanine Exchanger (AAE) family, in secondary transporters, according to the computational classification proposed by Saier et al. (http://www.biology.ucsd.edu/~msaier/transport/). We analyzed the topology of AspT biochemically, by using fusion methods in combination with alkaline phosphatase or beta-lactamase. These results suggested that AspT has a unique topology; 8 TMS, a large cytoplasmic loop (183 amino acids) between TMS5 and TMS6, and N- and C-termini that both face the periplasm. These results demonstrated a unique 2D-structure of AspT as the novel AAE family. 相似文献
989.
This paper reports a preparation method for silk sericin hydrogel using the Sericin-hope silkworm, whose cocoons consist almost exclusively of sericin. Sericin solution, prepared from Sericin-hope cocoons, contains intact sericin and forms elastic hydrogels with the addition of ethanol. The sericin hydrogel can be prepared without crosslinking by chemicals or irradiation and might be usable as a naturally occurring biomaterial. 相似文献
990.
Ishi K Maruyama J Juvvadi PR Nakajima H Kitamoto K 《Bioscience, biotechnology, and biochemistry》2005,69(4):747-754
Nuclear migration is indispensable for normal growth, differentiation, and development, and has been studied in several fungi including Aspergillus nidulans and Neurospora crassa. To better characterize nuclear movement and its consequences during conidiophore development, conidiation, and conidial germination, we performed confocal microscopy and time-lapse imaging on A. nidulans and Aspergillus oryzae strains expressing the histone H2B-EGFP fusion protein. Active trafficking of nuclei from a vesicle to a phialide and subsequently into a conidium provided the mechanistic basis for the formation of multinucleate conidia in A. oryzae. In particular, the first direct visual evidence on multinucleate conidium formation by the migration of nuclei from a phialide into the conidium, rather than by mitotic division in a newly formed conidium, was obtained. Interestingly, a statistical analysis on conidial germination revealed that conidia with more nuclei germinated earlier than those with fewer nuclei. Moreover, multinucleation of conidia conferred greater viability and resistance to UV-irradiation and freeze-thaw treatment. 相似文献