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241.
Gotoh K Inoue K Ogura A Oishi M 《Biochemical and biophysical research communications》2006,348(1):166-169
In-gel competitive reassociation (IGCR) is a method for differential subtraction of polymorphic (RFLP) DNA fragments between two DNA samples of interest without probes or specific sequence information. Here, we applied the IGCR procedure to two cloned mice derived from an F1 hybrid of the C57BL/6Cr and DBA/2 strains, in order to investigate the possibility of genomic alteration in the cloned mouse genomes. Each of the five of the genomic alterations we detected between the two cloned mice corresponded to the "intra-strain" polymorphisms in the C57BL/6Cr and DBA/2 mouse strains. Our result suggests that no severe aberration of genome sequences occurs due to somatic cell nuclear transfer. 相似文献
242.
Oishi P Azakie A Harmon C Fitzgerald RK Grobe A Xu J Hendricks-Munoz K Black SM Fineman JR 《American journal of physiology. Heart and circulatory physiology》2006,290(5):H1922-H1932
Several congenital heart defects require surgery that acutely increases pulmonary blood flow (PBF). This can lead to dynamic alterations in postoperative pulmonary vascular resistance (PVR) and can contribute to morbidity and mortality. Thus the objective of this study was to determine the role of nitric oxide (NO), endothelin (ET)-1, and their interactions in the alterations of PVR after surgically induced increases in PBF. Twenty lambs underwent placement of an aortopulmonary vascular graft. Lambs were instrumented to measure vascular pressures and PBF and studied for 4 h. Before and after shunt opening, lambs received an infusion of saline (n = 9), tezosentan, an ETA- and ETB -receptor antagonist (n = 6), or Nomega-nitro-L-arginine (L-NNA), a NO synthase (NOS) inhibitor (n = 5). In control lambs, shunt opening increased PBF by 117.8% and decreased PVR by 40.7% (P < 0.05) by 15 min, without further changes thereafter. Plasma ET-1 levels increased 17.6% (P < 0.05), and total NOS activity decreased 61.1% (P < 0.05) at 4 h. ET-receptor blockade (tezosentan) prevented the plateau of PBF and PVR, such that PBF was increased and PVR was decreased compared with controls at 3 and 4 h (P < 0.05). These changes were associated with an increase in total NOS activity (+61.4%; P < 0.05) at 4 h. NOS inhibition (L-NNA) after shunt placement prevented the sustained decrease in PVR seen in control lambs. In these lambs, PVR decreased by 15 min (P < 0.05) but returned to baseline by 2 h. Together, these data suggest that surgically induced increases in PBF are limited by vasoconstriction, at least in part by an ET-receptor-mediated decrease in lung NOS activity. Thus NO appears to be important in maintaining a reduction in PVR after acutely increased PBF. 相似文献
243.
244.
Kenji Tomita H. Akiko Popiel Yoshitaka Nagai Tatsushi Toda Yuji Yoshimitsu Hiroaki Ohno Shinya Oishi Nobutaka Fujii 《Bioorganic & medicinal chemistry》2009,17(3):1259-1263
Aggregation and deposition of expanded polyglutamine proteins in the brain cause neurodegenerative diseases including Huntington disease. This pathogenic process is suppressed and delayed in the presence of polyglutamine binding peptide 1 (QBP1), which we previously identified as an undecapeptide binding to pathogenic polyglutamine proteins from phage display peptide libraries. In this paper, a structure–activity relationship study on QBP1 was conducted to determine the pharmacophores for inhibition of polyglutamine aggregation. Furthermore, a truncation study identified an octapeptide as the minimum structure for suppressing aggregation of polyglutamine proteins, which is equipotent to the parent undecapeptide QBP1. 相似文献
245.
Edoardo Daly Sari Palmroth Paul Stoy Mario Siqueira A. Christopher Oishi Jehn-Yih Juang Ram Oren Amilcare Porporato Gabriel G. Katul 《Biogeochemistry》2009,94(3):271-287
Profiles of subsurface soil CO2 concentration, soil temperature, and soil moisture, and throughfall were measured continuously during the years 2005 and
2006 in 16 locations at the free air CO2 enrichment facility situated within a temperate loblolly pine (Pinus taeda L.) stand. Sampling at these locations followed a 4 by 4 replicated experimental design comprised of two atmospheric CO2 concentration levels (ambient [CO2]a, ambient + 200 ppmv, [CO2]e) and two soil nitrogen (N) deposition levels (ambient, ambient + fertilization at 11.2 gN m−2 year−1). The combination of these measurements permitted indirect estimation of belowground CO2 production and flux profiles in the mineral soil. Adjacent to the soil CO2 profiles, direct (chamber-based) measurements of CO2 fluxes from the soil–litter complex were simultaneously conducted using the automated carbon efflux system. Based on the
measured soil CO2 profiles, neither [CO2]e nor N fertilization had a statistically significant effect on seasonal soil CO2, CO2 production, and effluxes from the mineral soil over the study period. Soil moisture and temperature had different effects
on CO2 concentration depending on the depth. Variations in CO2 were mostly explained by soil temperature at deeper soil layers, while water content was an important driver at the surface
(within the first 10 cm), where CO2 pulses were induced by rainfall events. The soil effluxes were equal to the CO2 production for most of the time, suggesting that the site reached near steady-state conditions. The fluxes estimated from
the CO2 profiles were highly correlated to the direct measurements when the soil was neither very dry nor very wet. This suggests
that a better parameterization of the soil CO2 diffusivity is required for these soil moisture extremes. 相似文献
246.
Takayoshi Matsumura Toru Suzuki Kenichi Aizawa Daigo Sawaki Yoshiko Munemasa Junichi Ishida Ryozo Nagai 《The Journal of biological chemistry》2009,284(51):35861-35871
Abnormal transforming growth factor-β (TGF-β) signaling is a critical contributor to the pathogenesis of various human diseases ranging from tissue fibrosis to tumor formation. Excessive TGF-β signaling stimulates fibrotic responses. Recent research has focused in the main on the antiproliferative effects of TGF-β in fibroblasts, and it is presently understood that TGF-β-stimulated cyclooxygenase-2 (COX-2) induction in fibroblasts is essential for antifibroproliferative effects of TGF-β. Both TGF-β and COX-2 have been implicated in tumor growth, invasion, and metastasis, and therefore tumor-associated fibroblasts are a recent topic of interest. Here we report the identification of positive and negative regulatory factors of COX-2 expression induced by TGF-β as determined using proteomic approaches. We show that TGF-β coordinately up-regulates three factors, heterogeneous nuclear ribonucleoprotein A/B (HNRPAB), nucleotide diphosphate kinase A (NDPK A), and nucleotide diphosphate kinase A (NDPK B). Functional pathway analysis showed that HNRPAB augments mRNA and protein levels of COX-2 and subsequent prostaglandin E2 (PGE2) production by suppressing degradation of COX-2 mRNA. In contrast, NDPK A and NDPK B attenuated mRNA and protein levels of COX-2 by affecting TGF-β-Smad2/3/4 signaling at the receptor level. Collectively, we report on a new regulatory pathway of TGF-β in controlling expression of COX-2 in fibroblasts, which advances our understanding of pathophysiological mechanisms of TGF-β. 相似文献
247.
Oishi I 《Bioscience, biotechnology, and biochemistry》2010,74(12):2426-2430
Chicken primordial germ cells (PGCs) differentiate into germ cells in gonads. Because PGCs can be cloned and cultured maintaining germline competency, they are a good means of modifying the chicken genome, but the efficiency of plasmid transfection into PGCs is very low. In this study, I attempted to improve the efficiency of PGC transfection. Cultured PGCs were purified by Percoll density gradient centrifugation, and were then transfected with plasmid DNA. For transient transfection, the transfection efficiency increased more than 7-fold by the Percoll method. The efficiency of stable transfection of PGCs also increased significantly. The stable transfectants that were isolated by this method accumulated in the developing gonads after microinjection into bloodstream of chick embryos, indicating that gene transfection by Percoll purification did not alter the function of PGCs in vivo. 相似文献
248.
Masaki Igarashi Jun-ichi Osuga Masashi Isshiki Motohiro Sekiya Hiroaki Okazaki Satoru Takase Mikio Takanashi Keisuke Ohta Masayoshi Kumagai Makiko Nishi Toshiro Fujita Ryozo Nagai Takashi Kadowaki Shun Ishibashi 《Journal of lipid research》2010,51(2):274-285
Neutral cholesterol ester hydrolase (NCEH) accounts for a large part of the nCEH activity in macrophage foam cells, a hallmark of atherosclerosis, but its subcellular localization and structure-function relationship are unknown. Here, we determined subcellular localization, glycosylation, and nCEH activity of a series of NCEH mutants expressed in macrophages. NCEH is a single-membrane-spanning type II membrane protein comprising three domains: N-terminal, catalytic, and lipid-binding domains. The N-terminal domain serves as a type II signal anchor sequence to recruit NCEH to the endoplasmic reticulum (ER) with its catalytic domain within the lumen. All of the putative N-linked glycosylation sites (Asn270, Asn367, and Asn389) of NCEH are glycosylated. Glycosylation at Asn270, which is located closest to the catalytic serine motif, is important for the enzymatic activity. Cholesterol loading by incubation with acetyl-LDL does not change the ER localization of NCEH. In conclusion, NCEH is targeted to the ER of macrophages, where it hydrolyzes CE to deliver cholesterol for efflux out of the cells. 相似文献
249.
Respati T. Swasono Ryota Mouri Nagy Morsy Nobuaki Matsumori Tohru Oishi Michio Murata 《Bioorganic & medicinal chemistry letters》2010,20(7):2215-2218
The affinity of amphidinol 3 (AM3) to phospholipid membranes in the presence and absence of sterol was examined by surface plasmon resonance (SPR) experiments. The results showed that AM3 has 1000 and 5300 times higher affinity for cholesterol- and ergosterol-containing liposomes, respectively, than those without sterol. The two-state reaction model well reproduced the sensor grams, which indicated that the interaction is composed of two steps, which correspond to binding to the membrane and internalization to form stable complexes. 相似文献
250.
Comparative Gene Expression Analysis of Susceptible and Resistant Near-Isogenic Lines in Common Wheat Infected by Puccinia triticina 总被引:1,自引:0,他引:1
Alagu Manickavelu Kanako Kawaura Kazuko Oishi Tadasu Shin-I Yuji Kohara Nabila Yahiaoui Beat Keller Ayako Suzuki Kentaro Yano Yasunari Ogihara 《DNA research》2010,17(4):211-222
Gene expression after leaf rust infection was compared in near-isogenic wheat lines differing in the Lr10 leaf rust resistance gene. RNA from susceptible and resistant plants was used for cDNA library construction. In total, 55 008 ESTs were sequenced from the two libraries, then combined and assembled into 14 268 unigenes for further analysis. Of these ESTs, 89% encoded proteins similar to (E value of ≤10−5) characterized or annotated proteins from the NCBI non-redundant database representing diverse molecular functions, cellular localization and biological processes based on gene ontology classification. Further, the unigenes were classified into susceptible and resistant classes based on the EST members assembled from the respective libraries. Several genes from the resistant sample (14-3-3 protein, wali5 protein, actin-depolymerization factor and ADP-ribosylation factor) and the susceptible sample (brown plant hopper resistance protein, caffeic acid O-methyltransferase, pathogenesis-related protein and senescence-associated protein) were selected and their differential expression in the resistant and susceptible samples collected at different time points after leaf rust infection was confirmed by RT–PCR analysis. The molecular pathogenicity of leaf rust in wheat was studied and the EST data generated made a foundation for future studies. 相似文献