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101.
Ikonomou G Kostourou V Shirasawa S Sasazuki T Samiotaki M Panayotou G 《Journal of Proteomics》2012,75(17):5356-5369
Mutation of RAS genes is one of the most common oncogenic alterations in cancer and acquisition of activating RAS mutations has been demonstrated to cause progression of colorectal adenoma to cancer. The aim of this study was to identify changes in the proteome of the intermediate-stage colorectal cancer cell line Caco2, induced by ectopic expression of two distinct RAS proteins, KRAS(V12) and HRAS(V12), in their mutated, constitutively active form. Using 2D-gel electrophoresis, followed by LC-MS/MS we identified almost 200 differentially expressed proteins in pair-wise comparisons of Caco2 vs Caco2-KRAS(V12) and Caco2 vs Caco2-HRAS(V12). Although many of the affected proteins were unique for each pair, there were also substantial similarities. Interestingly, transformation by the mutant KRAS(V12) gene resulted in elevated expression levels and activity of endogenous H-ras protein. Silencing the latter with a specific RNAi reversed several proteomic changes observed in KRAS(V12)-transformed cells, suggesting that oncogenic K-ras partly exerts its effects through endogenous H-ras activation. Alterations in the expression of cytoskeletal and cell adhesion proteins, caused by HRAS siRNA treatment, correlated with a reduction in the invasive properties of Caco2-KRAS(V12) cells. Our data suggest a novel interplay between K-ras and H-ras, with possible implications for colorectal carcinogenesis. 相似文献
102.
Taku Inohara Shun Kohsaka Naoki Sato Katsuya Kajimoto Takehiko Keida Masayuki Mizuno Teruo Takano 《PloS one》2014,9(9)
Background
Renal dysfunction associated with acute decompensated heart failure (ADHF) is associated with impaired outcomes. Its mechanism is attributed to renal arterial hypoperfusion or venous congestion, but its prognostic impact based on each of these clinical profiles requires elucidation.Methods and Results
ADHF syndromes registry subjects were evaluated (N = 4,321). Logistic regression modeling calculated adjusted odds ratios (OR) for in-hospital mortality for patients with and without renal dysfunction. Renal dysfunction risk was calculated for subgroups with hypoperfusion-dominant (eg. cold extremities, a low mean blood pressure or a low proportional pulse pressure) or congestion-dominant clinical profiles (eg. peripheral edema, jugular venous distension, or elevated brain natriuretic peptide) to evaluate renal dysfunction''s prognostic impact in the context of the two underlying mechanisms. On admission, 2,150 (49.8%) patients aged 73.3±13.6 years had renal dysfunction. Compared with patients without renal dysfunction, those with renal dysfunction were older and had dominant ischemic etiology jugular venous distension, more frequent cold extremities, and higher brain natriuretic peptide levels. Renal dysfunction was associated with in-hospital mortality (OR 2.36; 95% confidence interval 1.75–3.18, p<0.001), and the prognostic impact of renal dysfunction was similar in subgroup of patients with hypoperfusion- or congestion-dominant clinical profiles (p-value for the interaction ranged from 0.104–0.924, and was always >0.05).Conclusions
Baseline renal dysfunction was significantly associated with in-hospital mortality in ADHF patients. The prognostic impact of renal dysfunction was the same, regardless of its underlying etiologic mechanism. 相似文献103.
The settling flux of seston (dry weight, DW), chlorophyll a (Chl a), particulate organic carbon (POC), particulate organic nitrogen (PON), and particulate phosphorus (PP) was measured monthly in 1981–1983 at 10 different depths in Lake Chuzenji, Japan; an oligotrophic lake with a maximum depth of 163 m. The Ti concentration in entrapped matter was used to separate the sedimentation flux into allochthonous and autochthonous components. Inflow loads of dissolved nutrients (DN: 4.5, DP: 0.48 g m-2a-1) were almost sufficient to supply the autochthonous fluxes at 30 m (PON: 2.9, PP: 0.51 g m-2a-1 ), and this flux of POC (26.6 g m-2a -1) was about one-third of primary production (84 g C M-2a-1). Sedimentation of particulate matter was the main path of losing nutrients from lake water, explaining more than 80% removal of inflow loads (TN, TP). Decomposition rates during sedimentation which were calculated from the vertical difference in the autochthonous flux agreed very closely with the results obtained by laboratory experiments of a 100-day incubation (content ratios from field observations were: POC 0.67, PON 0.65, PP 0.85; and from laboratory experiments they were: POC 0.68, PON 0.70, PP 0.94). These decomposition rates and those near the sediment interface were used to explain dissolved oxygen depletion and nitrate increase in the hypolimnion during stratification. The average sinking velocities were 1.82m d-1 for seston and 1.16 m d-1 for Chl a at 30m, they were influenced by Chl a content of seston. 相似文献
104.
105.
Naka T Nakata N Maeda S Yamamoto R Doe M Mizuno S Niki M Kobayashi K Ogura H Makino M Fujiwara N 《Journal of bacteriology》2011,193(20):5766-5774
The Mycobacterium avium-M. intracellulare complex (MAIC) is divided into 28 serotypes by a species-specific glycopeptidolipid (GPL). Previously, we clarified the structures of serotype 7 GPL and two methyltransferase genes (orfA and orfB) in serotype 12 GPL. This study elucidated the chemical structure, biosynthesis gene, and host innate immune response of serotype 13 GPL. The oligosaccharide (OSE) structure of serotype 13 GPL was determined to be 4-2'-hydroxypropanoyl-amido-4,6-dideoxy-β-hexose-(1 → 3)-4-O-methyl-α-L-rhamnose-(1 → 3)-α-L-rhamnose-(1 → 3)-α-L-rhamnose-(1 → 2)-α-L-6-deoxy-talose by using chromatography, mass spectrometry, and nuclear magnetic resonance (NMR) analyses. The structure of the serotype 13 GPL was different from those of serotype 7 and 12 GPLs only in O-methylations. We found a relationship between the structure and biosynthesis gene cluster. M. intracellulare serotypes 12 and 13 have a 1.95-kb orfA-orfB gene responsible for 3-O-methylation at the terminal hexose, orfB, and 4-O-methylation at the rhamnose next to the terminal hexose, orfA. The serotype 13 orfB had a nonfunctional one-base missense mutation that modifies serotype 12 GPL to serotype 13 GPL. Moreover, the native serotype 13 GPL was multiacetylated and recognized via Toll-like receptor 2. The findings presented here imply that serotypes 7, 12, and 13 are phylogenetically related and confirm that acetylation of the GPL is necessary for host recognition. This study will promote better understanding of the structure-function relationships of GPLs and may open a new avenue for the prevention of MAIC infections. 相似文献
106.
Hearing vulnerability after noise exposure in a mouse model of reactive oxygen species overproduction 下载免费PDF全文
Shigefumi Morioka Hirofumi Sakaguchi Taro Yamaguchi Yuzuru Ninoyu Hiroaki Mohri Takashi Nakamura Yasuo Hisa Kiyokazu Ogita Naoaki Saito Takehiko Ueyama 《Journal of neurochemistry》2018,146(4):459-473
107.
Inactivation of kanamycin, neomycin, and streptomycin by enzymes obtained in cells of Pseudomonas aeruginoa 总被引:8,自引:0,他引:8 下载免费PDF全文
Ten strains of Pseudomonas aeruginosa were disrupted and centrifuged. The supernatant fluids from centrifugation at 105,000 x g contained enzymes inactivating kanamycin, neomycin, and streptomycin in the presence of adenosine triphosphate. Kanamycin-inactivating enzyme was precipitated with ammonium sulfate at 66% of saturated concentration, and the inactivated kanamycin was shown to be kanamycin-3'-phosphate in which the C-3 hydroxyl group of 6-amino-6-deoxy-d-glucose moiety was phosphorylated. This is identical with kanamycin inactivated by Escherichia coli carrying R factor. Streptomycin-inactivating enzyme was precipitated with ammonium sulfate at 33% of saturated concentration. 相似文献
108.
Yuki Sakamoto Jun Yamazaki Takayuki Yamada Jun Yokoyama Yuki Ogura‐Tsujita Masayuki Maki 《Plant Species Biology》2017,32(1):81-86
The diversity of mycorrhizal fungi among four Japanese Cephalanthera (Orchidaceae) species was examined at a total of seven sites, based on sequence variation in nuclear ribosomal DNA. This is the first report to detect mycorrhizal fungi in C. subaphylla. Two patterns of mycorrhizal associations were confirmed from our results. C. falcata has lower fungal specificity, associating with Russulaceae, Sebacinales and Thelephoraceae. By contrast, the three Cephalanthera species C. erecta, C. subaphylla, and C. longifolia were associated mainly with Thelephoraceae fungi. There is no large difference found in mycobionts between green and albino individuals of C. falcata and no distinct preference of Japanese Cephalanthera species for a specific fungal group of Thelephoraceae. 相似文献
109.
Shotaro Sasaki Masaki Kobayashi Yuya Futagi Jiro Ogura Hiroaki Yamaguchi Natsuko Takahashi Ken Iseki 《PloS one》2013,8(7)
Background
Monocarboxylate transporters (MCTs) transport monocarboxylates such as lactate, pyruvate and ketone bodies. These transporters are very attractive therapeutic targets in cancer. Elucidations of the functions and structures of MCTs is necessary for the development of effective medicine which targeting these proteins. However, in comparison with MCT1, there is little information on location of the function moiety of MCT4 and which constituent amino acids govern the transport function of MCT4. The aim of the present work was to determine the molecular mechanism of L-lactate transport via hMCT4.Experimental approach
Transport of L-lactate via hMCT4 was determined by using hMCT4 cRNA-injected Xenopus laevis oocytes. hMCT4 mediated L-lactate uptake in oocytes was measured in the absence and presence of chemical modification agents and 4,4′-diisothiocyanostilbene-2,2′-disulphonate (DIDS). In addition, L-lactate uptake was measured by hMCT4 arginine mutants. Immunohistochemistry studies revealed the localization of hMCT4.Results
In hMCT4-expressing oocytes, treatment with phenylglyoxal (PGO), a compound specific for arginine residues, completely abolished the transport activity of hMCT4, although this abolishment was prevented by the presence of L-lactate. On the other hand, chemical modifications except for PGO treatment had no effect on the transport activity of hMCT4. The transporter has six conserved arginine residues, two in the transmembrane-spanning domains (TMDs) and four in the intracellular loops. In hMCT4-R278 mutants, the uptake of L-lactate is void of any transport activity without the alteration of hMCT4 localization.Conclusions
Our results suggest that Arg-278 in TMD8 is a critical residue involved in substrate, L-lactate recognition by hMCT4. 相似文献110.
Junko Morimoto Kento Hirabayashi Emu Mizumoto Takehiko Katsuno Yukihiro Morimoto 《Landscape and Ecological Engineering》2011,7(2):185-193
To develop an appropriate method of conservation for native Rhododendron sections Brachycalyx and Tsutsusi, the symbol of Satoyama, field experiments were performed in the dry granite region of Japan. When carpet-type landscape
of native rhododendrons was desired, all plants were cut at 20 cm above the ground level of all trees and shrubs, and herbs
and ferns were weeded (once and three times, respectively). When shrubby-type landscape of native rhododendrons was desired,
all plants, excluding native rhododendrons, were cut at 20 cm above the ground level of all trees and shrubs, herbs and ferns
were weeded, and litter was swept. After 3 years of monitoring of the percentage and depth of crowns with flower buds, the
following major results were obtained: Cutting all plants excluding native rhododendrons was effective to maintain the depth
of crowns with flower buds. However, weeding and sweeping of litter on the ground caused desiccation of surface soil, which
induced a transitory decrease in the percentage of crowns with flower buds. One weeding was effective in maintaining the depth
of crowns with flower buds; however, the second and third weedings had no distinct effect. In dry granite regions, considerable
attention to desiccation of surface soil is critical, as opposed to limiting attention to maintenance of sunlight as is common
practice. 相似文献