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141.
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
142.
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
143.
Photoaffinity cross-linking enables the analysis of interactions between DNA and proteins even under denaturing conditions. We present a photoaffinity electrophoretic mobility shift assay (EMSA) in which two heterogeneous techniques―photoaffinity cross-linking using DNA bearing 3-trifluoromethyl-3-phenyldiazirine and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE) analysis—are combined. To prepare the photoreactive DNA, which is an essential tool for photoaffinity EMSA, we first determined the optimal conditions for the integration of 4-(3-trifluoromethyl-3H-diazirin-3-yl)benzyl bromide to the specific site of oligonucleotide where phosphodiester linkage was replaced with phosphorothioate linkage. The photoaffinity EMSA was developed using the POU (initial letters of three genes: Pit-l, Oct-1,2, and unc-86) domain region of Oct-1 protein, which specifically bound to octamer DNA motif (ATGCAAAT). The affinity-purified recombinant POU domain proteins conjugated with glutathione-S-transferase (GST) contained three distinct proteins with molecular weights of 34, 36, and 45 kDa. The photoaffinity EMSA could clearly distinguish the individual binding abilities of three proteins on a single lane and showed that the whole POU domain protein specifically bound to octamer DNA motif by competition experiments. Using the nuclear extract of HeLa cells, the photoaffinity EMSA revealed that at least five specific proteins could bind to the octamer DNA motif. These results show that photoaffinity EMSA using 3-trifluoromethyl-3-phenyldiazirine can provide high-performance analysis of DNA-binding proteins. 相似文献
144.
Engineered bacterial sensors have potential applications in human health monitoring, environmental chemical detection, and materials biosynthesis. While such bacterial devices have long been engineered to differentiate between combinations of inputs, their potential to process signal timing and duration has been overlooked. In this work, we present a two‐input temporal logic gate that can sense and record the order of the inputs, the timing between inputs, and the duration of input pulses. Our temporal logic gate design relies on unidirectional DNA recombination mediated by bacteriophage integrases to detect and encode sequences of input events. For an E. coli strain engineered to contain our temporal logic gate, we compare predictions of Markov model simulations with laboratory measurements of final population distributions for both step and pulse inputs. Although single cells were engineered to have digital outputs, stochastic noise created heterogeneous single‐cell responses that translated into analog population responses. Furthermore, when single‐cell genetic states were aggregated into population‐level distributions, these distributions contained unique information not encoded in individual cells. Thus, final differentiated sub‐populations could be used to deduce order, timing, and duration of transient chemical events. 相似文献
145.
Indirect reciprocity is one of the major mechanisms of the evolution of cooperation. Because constant monitoring and accurate evaluation in moral assessments tend to be costly, indirect reciprocity can be exploited by cost evaders. A recent study crucially showed that a cooperative state achieved by indirect reciprocators is easily destabilized by cost evaders in the case with no supportive mechanism. Here, we present a simple and widely applicable solution that considers pre-assessment of cost evaders. In the pre-assessment, those who fail to pay for costly assessment systems are assigned a nasty image that leads to them being rejected by discriminators. We demonstrate that considering the pre-assessment can crucially stabilize reciprocal cooperation for a broad range of indirect reciprocity models. In particular for the most leading social norms, we analyse the conditions under which a prosocial state becomes locally stable. 相似文献
146.
Keiko Yasuma Jun-ichirou Yasunaga Keiko Takemoto Kenji Sugata Yuichi Mitobe Norihiro Takenouchi Masanori Nakagawa Yutaka Suzuki Masao Matsuoka 《PLoS pathogens》2016,12(1)
Human T-cell leukemia virus type 1 (HTLV-1) infects CD4+ T cells and induces proliferation of infected cells in vivo, which leads to the onset of adult T-cell leukemia (ATL) in some infected individuals. The HTLV-1 bZIP factor (HBZ) gene, which is encoded in the minus strand of HTLV-1, plays critical roles in pathogenesis. In this study, RNA-seq and ChIP-seq analyses using HBZ transduced T cells revealed that HBZ upregulates the expression and promoter acetylation levels of a co-inhibitory molecule, T cell immunoglobulin and ITIM domain (TIGIT), in addition to those of regulatory T cells related genes, Foxp3 and Ccr4. TIGIT was expressed on CD4+ T cells from HBZ-transgenic (HBZ-Tg) mice, and on ATL cells and HTLV-1 infected CD4+ T cells of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in vivo. Expression of Blimp1 and IL-10 was upregulated in TIGIT+CD4+ cells of HBZ-Tg mice compared with TIGIT-CD4+ T cells, suggesting the correlation between TIGIT expression and IL-10 production. When CD4+ T cells from HBZ-Tg mice were stimulated with TIGIT’s ligand, CD155, their production of the inhibitory cytokine IL-10 was enhanced. Furthermore, dendritic cells from HBZ-Tg mice produced high levels of IL-10 after stimulation. These data suggest that HBZ alters immune system to suppressive state via TIGIT and IL-10. Importantly, TIGIT suppressed T-cell responses to another HTLV-1 virus protein, Tax, in vitro. Blocking of TIGIT and PD-1 slightly increased anti-Tax T-cell activity in some HAM/TSP patients. These results suggest that HBZ-induced TIGIT on HTLV-1 infected cells impairs T-cell responses to viral antigens. This study shows that HBZ-induced TIGIT plays a pivotal role in attenuating host immune responses and shaping a microenvironment favorable to HTLV-1. 相似文献
147.
Katsumi Ajisaka Yutaka Oyanagi Tatsuo Miyazaki Yasuhiro Suzuki 《Bioscience, biotechnology, and biochemistry》2016,80(6):1179-1185
The antioxidant potencies of chondroitin sulfates (CSs) from shark cartilage, salmon cartilage, bovine trachea, and porcine intestinal mucosa were compared by three representative methods for the measurement of the antioxidant activity; DPPH radical scavenging activity, superoxide radical scavenging activity, and hydroxyl radical scavenging activity. CSs from salmon cartilage and bovine trachea showed higher potency in comparison with CSs from shark cartilage and porcine intestinal mucosa. Next, CS from salmon cartilage chelating with Ca2+, Mg2+, Mn2+, or Zn2+ were prepared, and their antioxidant potencies were compared. CS chelating with Ca2+ or Mg2+ ions showed rather decreased DPPH radical scavenging activity in comparison with CS of H+ form. In contrast, CS chelating with Ca2+ or Mg2+ ion showed remarkably enhanced superoxide radical scavenging activity than CS of H+ or Na+ form. Moreover, CS chelating with divalent metal ions, Ca2+, Mg2+, Mn2+, or Zn2+, showed noticeably higher hydroxyl radical scavenging activity than CS of H+ or Na+ form. The present results revealed that the scavenging activities of, at least, superoxide radical and hydroxyl radical were enhanced by the chelation with divalent metal ions. 相似文献
148.
Emerging solar cells, namely, organic solar cells and perovskite solar cells, are the thin‐film photovoltaics that have light to electricity conversion efficiencies close to that of silicon solar cells while possessing advantages in having additional functionalities, facile‐processability, and low fabrication cost. To maximize these advantages, the electrode components must be replaced by materials that are more flexible and cost‐effective. Researchers around the globe have been looking for the new electrodes that meet these requirements. Among many candidates, single‐walled carbon nanotubes have demonstrated their feasibility as the new alternative to conventional electrodes, such as indium tin oxide and metals. This review discusses various growth methods of single‐walled carbon nanotubes and their electrode applications in thin‐film photovoltaics. 相似文献
149.
150.
Yukie Sato Yoshiaki Tsuda Hironori Sakamoto Martijn Egas Tetsuo Gotoh Yutaka Saito Yan‐Xuan Zhang Jian‐Zhen Lin Jung‐Tai Chao Atsushi Mochizuki 《Ecology and evolution》2019,9(4):1590-1602
When males fight for access to females, such conflict rarely escalates into lethal fight because the risks and costs involved, that is, severe injury or death, are too high. The social spider mite, Stigmaeopsis miscanthi, does exhibit lethal male fights, and this male–male aggressiveness varies among populations. To understand the evolution of lethal fighting, we investigated aggressiveness in 42 populations and phylogenetic relationships in 47 populations along the Japanese archipelago. By analysis of the male weapon morph, a proxy for aggressiveness, we confirmed the existence of a mildly aggressive (ML) form, besides the low aggression (LW) and high aggression (HG) forms reported earlier. To evaluate demographic history of these three forms, we employed the approximate Bayesian computation approach using mtCOI sequences and taking into consideration the postlast glacial expansion history of the host plant, Miscanthus sinensis. As results, hierarchical split models are more likely to explain the observed genetic pattern than admixture models, and the ML form in the subtropical region was considered the ancestral group. The inferred demographic history was consistent with the one reconstructed for the host plant in a previous study. The LW form was split from the ML form during the last glacial period (20,000–40,000 years BP), and subsequently, the HG form was split from the ML form at the end of or after the last glacial period (5,494–10,988 years BP). The results also suggest that the mite invaded Japan more than once, resulting in the present parapatric distribution of LW and HG forms in eastern Japan. 相似文献