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951.
Koyama S Arawaka S Chang-Hong R Wada M Kawanami T Kurita K Kato M Nagai M Aoki M Itoyama Y Sobue G Chan PH Kato T 《Biochemical and biophysical research communications》2006,343(3):719-730
Accumulation of misfolded Cu/Zn superoxide dismutase (SOD1) occurs in patients with a subgroup of familial amyotrophic lateral sclerosis (fALS). To identify the conversion of SOD1 from a normally soluble form to insoluble aggregates, we investigated the change of SOD1 solubility with aging in fALS-linked H46R SOD1 transgenic mice. Mutant SOD1 specifically altered to insoluble forms, which were sequentially separated into Triton X-100-insoluble/sodium dodecyl sulfate (SDS)-soluble and SDS-insoluble/formic acid-soluble species. In spinal cords, the levels of SDS-dissociable soluble SOD1 monomers and SDS-stable soluble dimers were significantly elevated before motor dysfunction onset. In COS-7 cells expressing H46R SOD1, treatment with proteasome inhibitors recapitulated the alteration of SOD1 solubility in transgenic mice. In contrast, overexpression of Hsp70 reduced accumulation of mutant-specific insoluble SOD1. SDS-soluble low molecular weight species of H46R SOD1 may appear as early misfolded intermediates when their concentration exceeds the capacity of the proteasome and molecular chaperones. 相似文献
952.
Matsumura T Suzuki T Kada N Aizawa K Munemasa Y Nagai R 《Biochemical and biophysical research communications》2006,351(4):965-971
Protein profiling would aid in better understanding the pathophysiology of metabolic disease. Here, we report on differential proteomic analysis using an animal model of diabetes mellitus and associated metabolic disorders (Otsuka Long-Evans Tokushima Fatty rat). Serum was analyzed by a new two-dimensional liquid chromatography system which separated proteins by chromatofocusing and subsequent reversed-phase chromatography. This is the first application of this approach to differential serum proteomics. Differentially expressed proteins, identified with MALDI-TOF mass spectrometry, included apolipoproteins and alpha2-HS-glycoprotein. These findings add to our understanding of the underlying pathophysiology. This new proteomic analysis is a promising tool to elucidate disease mechanisms. 相似文献
953.
Arimitsu J Hirano T Higa S Kawai M Naka T Ogata A Shima Y Fujimoto M Yamadori T Hagiwara K Ohgawara T Kuwabara Y Kawase I Tanaka T 《Biochemical and biophysical research communications》2006,342(4):1413-1416
We previously demonstrated a significant association between IL-18 gene polymorphism 105A/C and asthma. In this study, we investigated the relationship of IL-18 gene polymorphism to IL-18 production capability by monocytes. The frequency of gene polymorphisms including IL-18-105A/C and IL-18--137G/C was determined by PCR analyses. The IL-18 production by monocytes stimulated without or with LPS or A23187+PMA for 1day was measured by ELISA. The produced IL-18 spontaneously or in response to A23187+PMA by monocytes was significantly higher for volunteers with 105A/A genotype than with 105A/C genotype. Similarly, the production capability of IL-18 by monocytes from volunteers with -137G/G genotype was significantly higher than that with -137G/C genotype and significant linkage disequilibrium was observed between 105A/C and -137G/C polymorphism. Thus, the genetic capacity to produce more IL-18 in response to stimuli may affect the onset of asthma. 相似文献
954.
955.
Michikami D Kamiya A Kawada T Inagaki M Shishido T Yamamoto K Ariumi H Iwase S Sugenoya J Sunagawa K Sugimachi M 《American journal of physiology. Heart and circulatory physiology》2006,291(1):H318-H326
Although electroacupuncture reduces sympathetic nerve activity (SNA) and arterial pressure (AP), the effects of electroacupuncture on the arterial baroreflex remain to be systematically analyzed. We investigated the effects of electroacupuncture of Zusanli on the arterial baroreflex using an equilibrium diagram comprised of neural and peripheral arcs. In anesthetized, vagotomized, and aortic-denervated rabbits, we isolated carotid sinuses and changed intra-carotid sinus pressure (CSP) from 40 to 160 mmHg in increments of 20 mmHg/min while recording cardiac SNA and AP. Electroacupuncture of Zusanli was applied with a pulse duration of 5 ms and a frequency of 1 Hz. An electric current 10 times the minimal threshold current required for visible muscle twitches was used and was determined to be 4.8 +/- 0.3 mA. Electroacupuncture for 8 min decreased SNA and AP (n = 6). It shifted the neural arc (i.e., CSP-SNA relationship) to lower SNA but did not affect the peripheral arc (i.e., SNA-AP relationship) (n = 8). SNA and AP at the closed-loop operating point, determined by the intersection of the neural and peripheral arcs, decreased from 100 +/- 4 to 80 +/- 9 arbitrary units and from 108 +/- 9 to 99 +/- 8 mmHg (each P < 0.005), respectively. Peroneal denervation eliminated the shift of neural arc by electroacupuncture (n = 6). Decreasing the pulse duration to <2.5 ms eliminated the effects of SNA and AP reduction. In conclusion, short-term electroacupuncture resets the neural arc to lower SNA, which moves the operating point toward lower AP and SNA under baroreflex closed-loop conditions. 相似文献
956.
Nucleolar protein B23 interacts with Japanese encephalitis virus core protein and participates in viral replication 总被引:1,自引:0,他引:1
Tsuda Y Mori Y Abe T Yamashita T Okamoto T Ichimura T Moriishi K Matsuura Y 《Microbiology and immunology》2006,50(3):225-234
Japanese encephalitis virus (JEV) core protein is detected not only in the cytoplasm but also in the nucleoli of infected cells. We previously showed that a mutant JEV lacking the nucleolar localization of the core protein impaired viral replication in mammalian cells. In this study, we identified a nucleolar phosphoprotein B23 as a protein binding with the core protein of JEV but not with that of dengue virus. The region binding with JEV core protein was mapped to amino acid residues 38 to 77 of B23. Upon JEV infection, some fraction of B23 was translocated from the nucleoli to the cytoplasm, and cytoplasmic B23 was colocalized with the core protein of wild-type JEV but not with that of the mutant JEV. Furthermore, overexpression of dominant negatives of B23 reduced JEV replication. These results suggest that B23 plays an important role in the intracellular localization of the core protein and replication of JEV. 相似文献
957.
Signaling axis in schwann cell proliferation and differentiation 总被引:3,自引:0,他引:3
958.
959.
A novel method for calculating the wood fiber length using a single cross section was devised and verified in Acacia mangium. This method is based on the ratio of cell tips to total cell number in a cross section related to the wood fiber. The fiber length was calculated using the single cross-section method and was compared with the measurements obtained using the conventional maceration method and the serial cross-section method. There was no significant difference among the three methods. 相似文献
960.
The structure and expression of SEPALLATA-like genes in Asparagus species (Asparagaceae) 总被引:2,自引:0,他引:2