139 research outputs found
Hierarchical Clustering of Ensemble Prediction Using LOOCV Predictable Horizon for Chaotic Time Series
Recently, we have presented a method of ensemble prediction of chaotic time series. The method employs strong learners capable of making predictions with small error, where usual ensemble mean does not work well owing to the long term unpredictability of chaotic time series. Thus, we have developed a method to select a representative prediction from a set of plausible predictions by means of using LOOCV (leave-one-out cross-validation) measure to estimate predictable horizon. Although we have shown the effectiveness of the method, it sometimes fails to select the representative prediction with long predictable horizon. In order to cope with this problem, this paper presents a method to select multiple candidates of representative prediction by means of employing hierarchical K-means clustering with K = 2. From numerical experiments, we show the effectiveness of the method and an analysis of the property of LOOCV predictable horizon.The 2017 IEEE Symposium Series on Computational Intelligence (IEEE SSCI 2017), November 27 to December 1, 2017, Honolulu, Hawaii, US
High temperature mechanical properties of BN particle dispersion SiC composites
Silicon carbide composites basically require weak fiber/matrix interphase like carbon or boron nitride (BN). The interphase material and its thickness are keys to determine mechanical properties. However precise control is the critical issue in terms of large scale production and material cost. The interphase is the weakest link for the environmental effects. The SiC composites were developed by applying BN particle dispersion in SiC matrix without the interphase. The objective is to understand the high temperature mechanical properties of the SiC composites.
Please click Additional Files below to see the full abstract
Black ginger extract increases physical fitness performance and muscular endurance by improving inflammation and energy metabolism
AbstractWe previously reported that polymethoxyflavones (PMFs) in black ginger (Kaempferia parviflora) extract (KPE) increased energy production by activating AMP-activated protein kinase (AMPK) in C2C12 myoblasts. We herein evaluated the effects of KPE on physical fitness performance and muscular endurance in mice. Male mice were orally administered KPE for 4 weeks, and then forced swimming test, open-field test, inclined plane test, and wire hanging test were performed. KPE significantly increased the swimming time, motility after swimming, and grip strength. IL-6 and TNF-α mRNA expression levels were decreased in the soleus muscle, whereas peroxisome proliferator-activated receptor γ coactivator (PGC)-1α and glycogen synthase mRNA expression levels, mitochondrial number, and glycogen content were increased. These results were in agreement with those obtained for KPE and PMFs in C2C12. Therefore, the activation of AMPK by PMFs may be one of the mechanisms by which KPE improves physical fitness performance and muscular endurance
Selective activation of STAT5 unveils its role in stem cell self-renewal in normal and leukemic hematopoiesis
Although the concept of a leukemic stem cell system has recently been well accepted, its nature and the underlying molecular mechanisms remain obscure. Constitutive activation of signal transducers and activators of transcription 3 (STAT3) and STAT5 is frequently detected in various hematopoietic tumors. To evaluate their role in normal and leukemic stem cells, we took advantage of constitutively active STAT mutants to activate STAT signaling selectively in hematopoietic stem cells (HSCs). Activation of STAT5 in CD34–c-Kit+Sca-1+ lineage marker– (CD34–KSL) HSCs led to a drastic expansion of multipotential progenitors and promoted HSC self-renewal ex vivo. In sharp contrast, STAT3 was demonstrated to be dispensable for the HSC maintenance in vivo, and its activation facilitated lineage commitment of HSCs in vitro. In a mouse model of myeloproliferative disease (MPD), sustained STAT5 activation in CD34–KSL HSCs but not in CD34+KSL multipotential progenitors induced fatal MPD, indicating that the capacity of STAT5 to promote self-renewal of hematopoietic stem cells is crucial to MPD development. Our findings collectively establish a specific role for STAT5 in self-renewal of normal as well as leukemic stem cells
頭皮皮膚血管肉腫に対する根治的な寡分割高線量放射線治療の実行可能性と有効性の検討
Cutaneous angiosarcoma is a rare but highly aggressive vascular tumor resistant to all treatment modalities available. The aim of this study was to analyze the treatment outcomes of patients who received definitive hypofractionated high-dose radiotherapy (RT) for angiosarcoma of the scalp. Between April 2008 and December 2014, 11 patients with histologically proven cutaneous angiosarcoma of the scalp visited our Department of Radiation Oncology, because dermatologists suggested that there was no indication for surgery in those cases. One patient rejected all radical treatments and the other 10 patients were treated by RT with curative intent along with chemotherapy or immunotherapy. Eight patients were treated with 6 - 12 MeV electron beams and the other 2 patients were treated with 4 MV X-ray Intensity Modulated Radiation Therapy (IMRT) and electron beams. The total irradiated dose was 63 - 75 Gy (median: 72.5 Gy) in 26 - 30 fractions, and the fraction size was 2.5 Gy in principle. The median age of the patients treated with RT was 80 years old (range: 73 - 91) and the median follow-up time was 16.5 months (range: 5.6 - 86.3). Four patients are still alive. A complete response (CR) was achieved in 10 patients (100%) and only one patient suffered local relapse 20 months after RT. Medians of overall survival (OS), progression-free survival (PFS), and local relapse-free survival (LRFS) were 38.7, 13.4, and 19.8 months, respectively. Local control rates were 100 and 75% at 1 and 2 years, respectively. Skin ulceration was CTCAE grade 2 in 5 patients (50%) and grade 3 in 5 (50%), alopecia was grade 2 in all patients (100%), but no patient developed grade 4 or more severe adverse events after RT. Hypofractionated high-dose RT was feasible and achieved excellent local control of cutaneous angiosarcoma in the elderly patients.博士(医学)・甲第646号・平成28年3月15日Copyright: © 2015 Shimoda E. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.The definitive version is available at " http://clinmedjournals.org/articles/ijccr/international-journal-of-cancer-and-clinical-research-ijccr-2-032.php?jid=ijccr
Gene expression profiling of loss of TET2 and/or JAK2V617F mutant hematopoietic stem cells from mouse models of myeloproliferative neoplasms
AbstractMyeloproliferative neoplasms (MPNs) are clinically characterized by the chronic overproduction of differentiated peripheral blood cells and the gradual expansion of malignant intramedullary/extramedullary hematopoiesis. In MPNs mutations in JAK2 MPL or CALR are detected mutually exclusive in more than 90% of cases [1,2]. Mutations in them lead to the abnormal activation of JAK/STAT signaling and the autonomous growth of differentiated cells therefore they are considered as “driver” gene mutations. In addition to the above driver gene mutations mutations in epigenetic regulators such as TET2 DNMT3A ASXL1 EZH2 or IDH1/2 are detected in about 5%–30% of cases respectively [3]. Mutations in TET2 DNMT3A EZH2 or IDH1/2 commonly confer the increased self-renewal capacity on normal hematopoietic stem cells (HSCs) but they do not lead to the autonomous growth of differentiated cells and only exhibit subtle clinical phenotypes [4,6–8,5]. It was unclear how mutations in such epigenetic regulators influenced abnormal HSCs with driver gene mutations how they influenced the disease phenotype or whether a single driver gene mutation was sufficient for the initiation of human MPNs. Therefore we focused on JAK2V617F and loss of TET2—the former as a representative of driver gene mutations and the latter as a representative of mutations in epigenetic regulators—and examined the influence of single or double mutations on HSCs (Lineage−Sca-1+c-Kit+ cells (LSKs)) by functional analyses and microarray whole-genome expression analyses [9]. Gene expression profiling showed that the HSC fingerprint genes [10] was statistically equally enriched in TET2-knockdown-LSKs but negatively enriched in JAK2V617F–LSKs compared to that in wild-type-LSKs. Double-mutant-LSKs showed the same tendency as JAK2V617F–LSKs in terms of their HSC fingerprint genes but the expression of individual genes differed between the two groups. Among 245 HSC fingerprint genes 100 were more highly expressed in double-mutant-LSKs than in JAK2V617F–LSKs. These altered gene expressions might partly explain the mechanisms of initiation and progression of MPNs which was observed in the functional analyses [9]. Here we describe gene expression profiles deposited at the Gene Expression Omnibus (GEO) under the accession number GSE62302 including experimental methods and quality control analyses
Surrounding Gastric Mucosa Findings Facilitate Diagnosis of Gastric Neoplasm as Gastric Adenoma or Early Gastric Cancer
Background and Aim. It is difficult to master the skill of discriminating gastric adenoma from early gastric cancer by conventional endoscopy or magnifying endoscopy combined with narrow-band imaging, because the colors and morphologies of these neoplasms are occasionally similar. We focused on the surrounding gastric mucosa findings in order to determine how to discriminate between early gastric cancer and gastric adenoma by analyzing the characteristics of the gastric background mucosa. Methods. We retrospectively examined 146 patients who underwent endoscopic submucosal dissection for gastric neoplasm between October 2009 and January 2015. The boundary of atrophic gastritis was classified endoscopically according to the Kimura-Takemoto classification system. Of 146 lesions, 63 early gastric cancers and 21 gastric adenomas were ultimately evaluated and assessed. Results. Almost all gastric adenomas were accompanied by open-type gastritis, whereas 47 and 16 early gastric cancers were accompanied by open-type and closed-type gastritis, respectively (p = 0.037). Conclusions. The evaluation of the boundary of atrophic gastritis associated with gastric neoplasms appears to be useful for discrimination between early gastric cancer and gastric adenoma. When gastric neoplasm is present in the context of surrounding localized gastric atrophy, gastric cancer is probable but not certain
Mice with Calr mutations homologous to human CALR mutations only exhibit mild thrombocytosis
Shide, K., Kameda, T., Kamiunten, A. et al. Mice with Calr mutations homologous to human CALR mutations only exhibit mild thrombocytosis. Blood Cancer J. 9, 42 (2019). https://doi.org/10.1038/s41408-019-0202-
- …