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11.
Yohei Miyanoiri Mitsuhiro Takeda Kosuke Okuma Akira M. Ono Tsutomu Terauchi Masatsune Kainosho 《Journal of biomolecular NMR》2013,57(3):237-249
The 1H–13C HMQC signals of the 13CH3 moieties of Ile, Leu, and Val residues, in an otherwise deuterated background, exhibit narrow line-widths, and thus are useful for investigating the structures and dynamics of larger proteins. This approach, named methyl TROSY, is economical as compared to laborious methods using chemically synthesized site- and stereo-specifically isotope-labeled amino acids, such as stereo-array isotope labeling amino acids, since moderately priced, commercially available isotope-labeled α-keto acid precursors can be used to prepare the necessary protein samples. The Ile δ1-methyls can be selectively labeled, using isotope-labeled α-ketobutyrates as precursors. However, it is still difficult to prepare a residue-selectively Leu and Val labeled protein, since these residues share a common biosynthetic intermediate, α-ketoisovalerate. Another hindering drawback in using the α-ketoisovalerate precursor is the lack of stereo-selectivity for Leu and Val methyls. Here we present a differential labeling method for Leu and Val residues, using four kinds of stereo-specifically 13CH3-labeled [U–2H;15N]-leucine and -valine, which can be efficiently incorporated into a protein using Escherichia coli cellular expression. The method allows the differential labeling of Leu and Val residues with any combination of stereo-specifically isotope-labeled prochiral methyls. Since relatively small amounts of labeled leucine and valine are required to prepare the NMR samples; i.e., 2 and 10 mg/100 mL of culture for leucine and valine, respectively, with sufficient isotope incorporation efficiency, this approach will be a good alternative to the precursor methods. The feasibility of the method is demonstrated for 82 kDa malate synthase G. 相似文献
12.
Yohei Takai Megumi Ohta Ryota Akagi Emika Kato Taku Wakahara Yasuo Kawakami Tetsuo Fukunaga Hiroaki Kanehisa 《Journal of physiological anthropology》2013,32(1):12
Background
The skeletal muscle mass of the lower limb plays a role in its mobility during daily life. From the perspective of physical resources, leg muscle mass dominantly decreases after the end of the fifth decade. Therefore, an accurate estimate of the muscle mass is important for the middle-aged and older population. The present study aimed to clarify the validity of ultrasound muscle thickness (MT) measurements for predicting leg skeletal muscle mass (SM) in the healthy Japanese middle-aged and older population.Findings
MTs at four sites of the lower limb and the bone-free lean tissue mass (LTM) of the right leg were determined using brightness-mode ultrasonography and dual-energy X-ray absorptiometry (DXA), respectively, in 44 women and 33 men, 52- to 78-years old. LTM was used as a representative variable of leg skeletal muscle mass. In the model-development group (30 women and 22 men), regression analysis produced an equation with R2 and standard error of the estimate (SEE) of 0.958 and 0.3 kg, respectively: LTM (kg) = 0.01464 × (MTSUM×L) (cm2) - 2.767, where MTSUM is the sum of the product of MTs at four sites, and L is length of segment where MT is determined. The estimated LTM (7.0 ± 1.7 kg) did not significantly differ from the measured LTM (7.0 ± 1.7 kg), without a significant systematic error on a Bland-Altman plot. The application of this equation for the cross-validation group (14 women and 11 men) did not yield a significant difference between the measured (7.2 ± 1.6 kg) or estimated (7.2 ± 1.6 kg) LTM and systematic error.Conclusion
The developed prediction equation may be useful for estimating the lean tissue mass of the lower extremity for the healthy Japanese middle-aged and older population. 相似文献13.
Shinichiro Tomitaka Yohei Kawasaki Kazuki Ide Maiko Akutagawa Hiroshi Yamada Toshiaki A. Furukawa Yutaka Ono 《PloS one》2016,11(11)
BackgroundSeveral studies have shown that total depressive symptom scores in the general population approximate an exponential pattern, except for the lower end of the distribution. The Center for Epidemiologic Studies Depression Scale (CES-D) consists of 20 items, each of which may take on four scores: “rarely,” “some,” “occasionally,” and “most of the time.” Recently, we reported that the item responses for 16 negative affect items commonly exhibit exponential patterns, except for the level of “rarely,” leading us to hypothesize that the item responses at the level of “rarely” may be related to the non-exponential pattern typical of the lower end of the distribution. To verify this hypothesis, we investigated how the item responses contribute to the distribution of the sum of the item scores.MethodsData collected from 21,040 subjects who had completed the CES-D questionnaire as part of a Japanese national survey were analyzed. To assess the item responses of negative affect items, we used a parameter r, which denotes the ratio of “rarely” to “some” in each item response. The distributions of the sum of negative affect items in various combinations were analyzed using log-normal scales and curve fitting.ResultsThe sum of the item scores approximated an exponential pattern regardless of the combination of items, whereas, at the lower end of the distributions, there was a clear divergence between the actual data and the predicted exponential pattern. At the lower end of the distributions, the sum of the item scores with high values of r exhibited higher scores compared to those predicted from the exponential pattern, whereas the sum of the item scores with low values of r exhibited lower scores compared to those predicted.ConclusionsThe distributional pattern of the sum of the item scores could be predicted from the item responses of such items. 相似文献
14.
Maiko Matsushita Yohei Otsuka Naoya Tsutsumida Chiaki Tanaka Akane Uchiumi Koji Ozawa Takuma Suzuki Daiju Ichikawa Hiroyuki Aburatani Shinichiro Okamoto Yutaka Kawakami Yutaka Hattori 《PloS one》2016,11(1)
The homeobox protein, PEPP2 (RHOXF2), has been suggested as a cancer/testis (CT) antigen based on its expression pattern. However, the peptide epitope of PEPP2 that is recognized by cytotoxic T cells (CTLs) is unknown. In this study, we revealed that PEPP2 gene was highly expressed in myeloid leukemia cells and some other hematological malignancies. This gene was also expressed in leukemic stem-like cells. We next identified the first reported epitope peptide (PEPP2271-279). The CTLs induced by PEPP2271-279 recognized PEPP2-positive target cells in an HLA-A*24:02-restricted manner. We also found that a demethylating agent, 5-aza-2’-deoxycytidine, could enhance PEPP2 expression in leukemia cells but not in blood mononuclear cells from healthy donors. The cytotoxic activity of anti-PEPP2 CTL against leukemic cells treated with 5-aza-2’-deoxycytidine was higher than that directed against untreated cells. These results suggest a clinical rationale that combined treatment with this novel antigen-specific immunotherapy together with demethylating agents might be effective in therapy-resistant myeloid leukemia patients. 相似文献
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Limnology - Microorganisms such as bacteria are considered to be control agents against toxic cyanobacterial blooms such as Microcystis aeruginosa. We investigated cyanobactericidal bacteria and... 相似文献
18.
Cul5-based complex is a member of ECS (Elongin B/C-Cul2/Cul5-SOCS-box protein) ubiquitin ligase family. The cellular function of the Cul5-based complex is poorly understood. In this study, we found that oocyte septum formation and egg production did not occur in either cul-5- or rbx-2-depleted cul-2 homozygotes, although control cul-2 homozygotes laid approximately 50 eggs. These phenotypes are reminiscent of those caused by the MAP kinase mpk-1 depletion. In fact, activation of MPK-1 was significantly inhibited in cul-5-depleted cul-2 mutant and cul-2-depleted cul-5 mutant. Yeast two-hybrid analysis and RNAi-knockdown experiments suggest that oocyte maturation from pachytene exit and MPK-1 activation are redundantly controlled by the RBX-2-CUL-5- and RBX-1-CUL-2-based complexes. 相似文献
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A simple chiral analysis of amino acid esters by fluorine‐19 nuclear magnetic resonance (19F NMR) through the modified James–Bull method is described. Thus, amino acid ester acid salt was treated with 5‐fluoro‐2‐formylphenylboronic acid and (S)‐BINOL in the presence of triethylamine (TEA) and MS4A for 10 minutes. The reaction mixture was analysed by 19F NMR directly to afford good quantifications. 相似文献