Metal Rich Plasma at the Center Portion of the Cygnus Loop

We observed the center portion of the Cygnus Loop supernova remnant with the ASCA observatory. The X-ray spectrum of the center portion was significantly different from that obtained at the North-East (NE) limb. The emission lines from Si and S were quite strong while those of O and the continuum emission were similar to those obtained at the NE limb. Based on the spectral analysis, Si and S emission lines originated from a high-kTe and low ionization plasma whereas O and most of the continuum emission arose from a low-kTe and high ionization plasma. We suppose that Si and S emitting gas are present at the interior of the Loop while O lines and continuum emission mainly arise from the shell region. Therefore, we subtracted the spectrum of the NE limb from that of the center. Obtained abundances of Si, S, and Fe were 4 $\pm$ 1, 6 $\pm$ 2, and ${1.3}^{+0.6}_{-0.3}$ times higher than those of the cosmic abundances, respectively, and are $\sim$40 times richer than those obtained at the NE limb. These facts strongly support that some of the crude ejecta must be left at the center portion of the Cygnus Loop. The low abundance of Fe relative to Si and S suggests a type II SN with a massive progenitor star as the origin of the Cygnus Loop.Comment: Accepted for Publications of the Astronomical Society of Japan, 40 pages, 12 Postscript figures, uses PASJ95.sty, PASJadd.sty, and psbox.st

キュウキュウ ニオケル ステロイド ゴウセイ コウソ ノ キョクザイ

Neurosteroids are synthesized through mechanism at least partly independent of the peripheral steroidogenic glands, and their neurobiological actions seem to depend on the specific functions of various brain regions. However, little is known about neurosteroids function corresponding to specific structure and functions of the brain regions. Thus the present study analyzed localization of steroid-synthesizing enzymes in the rat and mouse olfactory bulb. RT-PCR and Western-blotting indicated the possible presence of almost all enzymes of steroid synthesis from cholesterol to estradiol, that is, cholesterol side chain cleavage enzyme (P450scc : cholesterol→pregnenolone), 3β-hydroxysteroid dehydrogenase/Δ5 - 4 isomerase (3β-HSD : pregnenolone→progesterone), 17α-hydroxylase/C17-C20lyase (P450c17 : progesterone→ androstenedione), 17β-hydroxysteroid dehydrogenase (17β-HSD : androstenedione→testosterone), 5α-reductase (5αR:testosterone→5α-dihydrotestosterone), and aromatase (testosterone→ estradiol). Immunohistochemistry confirmed that the 5α-reductase was mainly in glial cells with various immunoreactivity and co-localization pattern, but other enzymes were in bulbar neurons, and at least co-localized in mitral/tufted cells. In addition, so far analyzed, enzymatic activities of P450c17 (a key enzyme in sex steroid synthesis) and 17β-HSD were detected biochemically. These enzyme expression and activities were influenced under exposure of 17β-estradiol with various degrees. These findings indicated the presence of steroid-synthesizing activities, and thus of possible neurosteroid metabolism in the olfactory bulb

Variation in the Encoding of Motion Events in Turkish

東京大学東京大学 大学院生東京外国語大学 学部生The University of TokyoGraduate Student, The University of TokyoUndergraduate Student, Tokyo University of Foreign Studies国立国語研究所における移動事象に関する通言語的プロジェクト（Motion Event Descriptions Across Languages，略称：MEDAL）は，移動事象表現の通言語的および個別言語的なバリエーションを研究する共同研究プロジェクトである。このプロジェクトの目的の1つは，ビデオを使った産出実験を行うことで，移動の経路が通言語的にどのようにコード化されているのかを解明することである。本論文では，典型的な経路主要部表示型言語といわれてきたトルコ語を対象にその実験を行った結果を報告する。この論文のもっとも重要な発見のひとつは，トルコ語が経路をコード化するときに経路の種類に応じてコード化のバリエーションを示すことである。経路FROM, TO.OUT, TO.IN, THROUGH, PAST, VIA.UNDER, VIA.BETWEEN, AROUND, ACROSS, UP, DOWNにおいては経路主要部表示型の表現パターンが支配的であるものの，経路ALONG, TO, TOWARDにおいては経路主要部外表示型の表現パターンが優勢である。こうして，本論文は，トルコ語の経路表示のパターンについてより細やかな一般化が必要であると指摘し，経路が違えば経路表示も異なるという事実に注目するべきであると主張する。この論文ではさらにトルコ語と他の言語の対照言語学的な違いについても言及する。The NINJAL project on Motion Event Descriptions Across Languages (MEDAL) is a collaborative research project on crosslinguistic and intralinguistic variations in motion event descriptions. One of the purposes of this project is to investigate how Path of motion is coded across languages by conducting a video-based production experiment. This paper reports the results of Experiment C undertaken on Turkish, an allegedly prime example of a verb-framed language. One of our important findings is that Turkish displays considerable variations in Path coding across different types of Path. A head Path-coding (≈ verb-framing) pattern is found to be dominant for the Path types of FROM, TO.OUT, TO.IN, THROUGH, PAST, VIA.UNDER, VIA.BETWEEN, AROUND, ACROSS, UP, and DOWN. In contrast, a head-external Pathcoding (≈ satellite-framing) pattern is found to be preferred for the Paths ALONG, TO, and TOWARD. Rather than simply assuming a consistent "verb-framed" pattern, we claim that a more nuanced generalization is required for Path-coding patterns in Turkish and that more attention should be paid to variations in Path coding among different types of Path. We further make a crosslinguistic comparison of Turkish with other languages supposedly of the same typological type such as Japanese and Spanish

Knockdown of E2F2 Inhibits Tumorigenicity, but\ud Preserves Stemness of Human Embryonic Stem Cells

Tumorigenicity of human pluripotent stem cells is a major threat limiting their application in cell therapy protocols. It remains unclear, however, whether suppression of tumorigenic potential can be achieved without critically affecting pluripotency. A previous study has identified hyperexpressed genes in cancer stem cells, among which is E2F2, a gene involved in malignant transformation and stem cell self-renewal. Here we tested whether E2F2 knockdown would affect proliferative capacity and tumorigenicity of human embryonic stem cells (hESC). Transient E2F2 silencing in hESC significantly inhibited expression of the proto-oncogenes BMI1 and HMGA1, in addition to proliferation of hESC, indicated by a higher proportion of cells in G1, fewer cells in G2/M phase, and a reduced capacity to generate hESC colonies in vitro. Nonetheless, E2F2-silenced cells kept expression of typical pluripotency markers and displayed differentiation capacity in vitro. More importantly, E2F2 knockdown in hESC significantly inhibited tumor growth in vivo, which were considerably smaller than tumors generated from control hESC, albeit displaying typical teratoma traits, a major indicator of pluripotency retention in E2F2- silenced cells. These results suggest that E2F2 knockdown can inhibit hESC proliferation and tumorigenicity without significantly harming stemness, providing a rationale to future protocols aiming at minimizing risks related to therapeutic application of cells and/or products derived from human pluripotent cells

Effects of sex and joint action on voluntary activation

The current study tested the hypothesis that voluntary activation during maximal voluntary contraction (MVC) conditionally depends on sex and joint action. Twenty-eight healthy adults (14 of each sex) performed knee extensor MVC and plantar flexor MVC at extended and flexed knee positions. Voluntary activation during MVC was assessed using a twitch interpolation technique. The voluntary activation during plantar flexor MVC at the extended knee position was significantly lower (P = 0.020, 95% confidence interval 1.4 to 14.6, Cohen’s d for between-subject design = 0.94) in women (88.3% ± 10.0%) than in men (96.2% ± 6.6%). In contrast, no significant sex differences were shown in the voluntary activation during knee extensor MVC (93.7% ± 5.9% (women) vs. 95.0%  ± 3.9% (men)) and during plantar flexor MVC at the flexed knee position (90.4% ± 12.2% (women) vs. 96.8% ± 5.6% (men)). The voluntary activation during knee extensor MVC was significantly higher (P = 0.001, 95% confidence interval 2.1 to 8.8, Cohen’s d for within-subject design = 0.69) than that during plantar flexor MVC at the extended knee position in women, whereas the corresponding difference was not observed in men. The results revealed that the existence of sex difference in the voluntary activation during MVC depends on joint action and joint angle

Scaling the stimulated emission of polarization-entangled photons using passive optical components

Bright sources of polarization-entangled photon pairs are essential components for quantum information technologies. In general, it is necessary to introduce a resonator that combines active optical components such as an electric optical modulator to enhance the stimulated emission of polarization-entangled photons. It is technically difficult to perform the time series operation to output the stimulated entangled photons in the resonator by synchronizing laser pulses. In this paper, we propose a scheme to scale up the stimulated emission of polarization-entangled photon pairs using a resonator with only passive optical components. We show the theoretical aspects of the scheme and also perform a proof-of-principle experimental demonstration of the scheme in a double-pass configuration.Comment: 8 pages, 6 figures, Physical Review A to be publishe

Key role for transforming growth factor-β in melanocyte stem cell immaturity and quiescence

Division of Stem Cell Medicin

Screening for yeast mutants defective in recipient ability for transkingdom conjugation with Escherichia coli revealed importance of vacuolar ATPase activity in the horizontal DNA transfer phenomenon

Proteobacterium Escherichia coli strains harboring wide-transfer-range conjugative plasmids are able to transfer these plasmids to several yeast species. Whole plasmid DNA is mobilizable in the transkingdom conjugation phenomenon. Owing to the availability of various conjugative plasmids in bacteria, the horizontal DNA transfer has potential to occur between various bacteria and eukaryotes. In order to know host factor genes involved in such conjugation, we systematically tested the conjugability of strains among a yeast library comprising single-gene-knockout mutants in this study. This genome-wide screen identified 26 host chromosomal genes whose absence reduced the efficiency of the transkingdom conjugation. Among the 26 genes, 20 are responsible for vacuolar ATPase activity, while 5 genes (SHP1, CSG2, CCR4, NOT5, and HOF1) seem to play a role in maintaining the cell surface. Lack of either ZUO1 gene or SSZ1 gene, each of which encodes a component of the ribosome-associated cytoplasmic molecular chaperone, also strongly affected transkingdom conjugation.This work was supported in part by Japanese Ministry of Education, Science, Sports and Culture, Grant-in-Aid for Scientific Research (#20570221)

Diagnosis, Pathological Findings, and Clinical Management of Gangliocytic Paraganglioma: A Systematic Review

Background: Although gangliocytic paraganglioma (GP) is considered a rare benign neuroendocrine tumor, cases of mortality have been reported. Occasionally, GP is misdiagnosed as neuroendocrine tumor G1, which is associated with a poorer prognosis than GP. To avoid such misdiagnoses, it is important to understand the clinicopathological characteristics of GP. Thus, herein, we discuss the current literature on the clinicopathological characteristics of GP.Methods: We conducted a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. PubMed and Japana Centra Revuo Medicina searches were used to identify papers describing GP. Inclusion criteria included confirmation of epithelioid, spindle-shaped, and ganglion-like cells in the main article and/or figures and whether the paper was cited in other studies of GP. Data were collected on age, sex, site of the primary lesion, tumor size, treatment, prognosis, lymph node metastasis (LNM), depth of tumor invasion, rate of preoperative diagnosis, and clinical symptoms.Results: In total, 162 papers containing 263 cases of GP met the criteria. The mean age at diagnosis was 53.5 years. The male-to-female ratio was 157:104. The mean tumor size was 25.7 mm. The predominant site of the primary tumor was the duodenum (89.7%). The most common clinical sign of GP was gastrointestinal bleeding (47.9%). Other signs and symptoms of GP included abdominal pain (44.7%), anemia (20.3%), incidental findings (12.9%), nausea (6.9%), weight loss (5.5%), general fatigue (5.1%), jaundice (4.6%), and incidental autopsy findings (5.1%). LNM was observed in 11.4% of patients. Liver metastasis was observed in 1.1% of patients. Depth of tumor invasion (penetrating beyond the submucosal layer or sphincter of Oddi) was by far the most significant risk factor for LNM in patients with GP. This suggests, along with histological heterogeneity, that GP may have hamartomatous characteristics. Furthermore, immunohistochemical expression of progesterone receptor and pancreatic polypeptide were useful in distinguishing between GP and neuroendocrine tumor G1, even in small biopsy specimens.Conclusions: We reveal the clinicopathological characteristics of GP, including risk factors for LNM, differential diagnostic approaches, and improvements in the clinical management of this tumor.In addition, GP may have hamartomatous characteristics

Zinc is a novel intracellular second messenger

Zinc is an essential trace element required for enzymatic activity and for maintaining the conformation of many transcription factors; thus, zinc homeostasis is tightly regulated. Although zinc affects several signaling molecules and may act as a neurotransmitter, it remains unknown whether zinc acts as an intracellular second messenger capable of transducing extracellular stimuli into intracellular signaling events. In this study, we report that the cross-linking of the high affinity immunoglobin E receptor (Fcɛ receptor I [FcɛRI]) induced a release of free zinc from the perinuclear area, including the endoplasmic reticulum in mast cells, a phenomenon we call the zinc wave. The zinc wave was dependent on calcium influx and mitogen-activated protein kinase/extracellular signal-regulated kinase kinase activation. The results suggest that the zinc wave is involved in intracellular signaling events, at least in part by modulating the duration and strength of FcɛRI-mediated signaling. Collectively, our findings indicate that zinc is a novel intracellular second messenger