32 research outputs found
Deep Near-Infrared Imaging af an Embedded Cluster in the Extreme Outer Galaxy: Census of Supernovae Triggered Star Formation
While conducting a near-infrared (NIR) survey of ``Digel Clouds'', which are
thought to be located in the extreme outer Galaxy (EOG), Kobayashi & Tokunaga
found star formation activity in ``Cloud 2'', a giant molecular cloud at the
Galactic radius of ~ 20 kpc. Additional infrared imaging showed two embedded
young clusters at the densest regions of the molecular cloud. Because the
molecular cloud is located in the vicinity of a supernova remnant (SNR) HI
shell, GSH 138-01-94, it was suggested that the star formation activity in
Cloud 2 was triggered by this expanding HI shell. We obtained deep J (1.25 um),
H (1.65 um) and K (2.2 um) images of one of the embedded clusters in Cloud 2
with high spatial resolution (FWHM ~0".3) and high sensitivity (K ~ 20 mag, 10
sigma). We identified 52 cluster members. The estimated stellar density (~ 10
pc^{-2}) suggests that the cluster is a T-association. This is the deepest NIR
imaging of an embedded cluster in the EOG. The observed K-band luminosity
function (KLF) suggests that the underlying initial mass function (IMF) of the
cluster down to the detection limit of ~ 0.1 M_sun is not significantly
different from the typical IMFs in the field and in the near-by star clusters.
The overall characteristics of this cluster appears to be similar to those of
other embedded clusters in the far outer Galaxy. The estimated age of the
cluster from the KLF, which is less than 1 Myr, is consistent with the view
that the star formation was triggered by the HI shell whose age was estimated
at 4.3 Myr (Stil & Irwin). The 3-dimensional geometry of SNR shell, molecular
cloud and the embedded cluster, which is inferred from our data, as well as the
cluster age strongly suggest that the star formation in Cloud 2 was triggered
by the SNR shell.Comment: 19pages, 8 figures, 1 table, accepted to ApJ. Full paper (pdf) with
high resolution figures available at
http://www.ioa.s.u-tokyo.ac.jp/~ck_yasui/papers/Cloud2N_1.pd
Amygdala granular fuzzy astrocytes as lesions preceding development of argyrophilic grains: data from 239 autopsy cases
Astrocytic Tau Pathologies in Argyrophilic Grain Disease and Related Four-repeat Tauopathies
Neurodegenerative diseases in which tau accumulation plays a cardinal role in the pathogenic process are called tauopathies, and when tau isoforms having four repeats of the microtubule binding sites, four-repeat tau, are selectively accumulated as pathological hallmarks, the term four-repeat tauopathy is used. The major four-repeat tauopathies are progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), and argyrophilic grain disease (AGD). Historically, neuronal cytopathologies, e.g., neurofibrillary tangles and ballooned neurons, were emphasized as characteristic lesions in PSP and CBD. Now, however, astrocytic tau pathologies, i.e., tufted astrocytes (TAs) and astrocytic plaques (APs), are considered to be highly disease-specific lesions. Although granular/fuzzy astrocytes (GFAs) frequently develop in the limbic system in AGD cases, the specificity is not conclusive yet. Some AGD cases have a few TAs, and to a lesser frequency, a few APs in the frontal cortex and subcortical nuclei. The number of astrocytic tau pathologies including TAs and GFAs increases with the progression of AGD. In this paper, histopathological features of astrocytic tau pathologies in PSP, CBD, and AGD are first reviewed. Then, recent findings regarding the coexistence of these tauopathies are summarized from a viewpoint of astrocytic tau pathologies. Further biochemical and pathological studies focusing tau-positive astrocytic lesions may be useful to increase understanding of the pathological process in four-repeat tauopathies and to develop novel therapeutic strategies for patients with these diseases
Star Formation in the Extreme Outer Galaxy: Digel Cloud 2 Clusters
As a first step for studying star formation in the extreme outer Galaxy
(EOG), we obtained deep near-infrared images of two embedded clusters at the
northern and southern CO peaks of Cloud 2, which is one of the most distant
star forming regions in the outer Galaxy (galactic radius R_g ~ 19 kpc). With
high spatial resolution (FWHM ~ 0".35) and deep imaging (K ~ 21 mag) with the
IRCS imager at the Subaru telescope, we detected cluster members with a mass
detection limit of < 0.1 M_{sun}, which is well into the substellar regime.
These high quality data enables a comparison of EOG to those in the solar
neighborhood on the same basis for the first time. Before interpreting the
photometric result, we have first constructed the NIR color-color diagram
(dwarf star track, classical T Tauri star (CTTS) locus, reddening law) in the
Mauna Kea Observatory filter system and also for the low metallicity
environment since the metallicity in EOG is much lower than those in the solar
neighborhood. The estimated stellar density suggests that an ``isolated type''
star formation is ongoing in Cloud 2-N, while a ``cluster type'' star formation
is ongoing in Cloud 2-S. Despite the difference of the star formation mode,
other characteristics of the two clusters are found to be almost identical: (1)
K-band luminosity function (KLF) of the two clusters are quite similar, as is
the estimated IMF and ages (~ 0.5--1 Myr) from the KLF fitting, (2) the
estimated star formation efficiencies (SFEs) for both clusters are typical
compared to those of embedded clusters in the solar neighborhood (~ 10 %). The
similarity of two independent clusters with a large separation (~ 25 pc)
strongly suggest that their star formation activities were triggered by the
same mechanism, probably the supernova remnant (GSH 138-01-94).Comment: 14pages, 11 figures; Accepted for publication in Ap
ユリ根中トリプシンインヒビター(LTI-II-4)の精製とその性質
Several proteins from lily bulb for foodstuffs showed strong inhibitory activity toward bovine trypsin. A trypsin inhibitor (LTI-II-4) was purified from lily bulb by a method including column chromatographies on CM-Sepharose CL-6B and DEAE-Sepharose GL-6B and high-pressure liquid chromatography. Purified LTI-II-4 had a molecular weight of 21,000. The amino acid composition was characterized by high contents of glycine, aspartic acid and serine. The inhibitor contained 4 halfcystines in its constituent amino acids. The N-terminal 25 and the C-terminal 3 residues of LTI-II-4 were sequenced. The Inhibitor was stable in a wide pH range under 50℃ and was unstable at the higher temperatures than 80℃. The reactivesite amino acid of LTI-II-4 was assumed to be lysine. The inhibitor didn\u27t inhibit elastase and subtilisin. From these results, the inhibitor LTI-II-4 is assumed to belong to the Kunitz soybean trypsin inhibitor family
卵アレルギー患者血清によるIgE結合卵白抗原の検索 : ニワトリ,ウズラ,アヒル卵の主要タンパク質について
IgE binding antigen of the major proteins in egg white, which is hen (H), quail (Q) and duck (D) was determined using the sera of patients with egg allergy. The major proteins of egg white were ovotransferrin (OT), ovoinhibitor (OI), ovalbumin (OA), ovomucoid (OM) and lysozyme (LY). The age of egg allergy patients is used this present studey were 3 years 4 months-old to 4 months-old (RAST 2~6). After SDS-PAGE analysis of egg whites, Western-blotting and enzyme-immunoassay was examined using the serum of 33 patoents with egg allergy. The positive blots of IgE binding proteins were ranked score 1~5 by positive color. The blots from score 2 to score 5 were positive of IgE binding. The positive percent of IgE blotting to hen OM was shown to have higher positive percent relatively to the other major proteins with the serum of 33 patients. And, on the sera of RAST 3 and RAST 4~6, ratio of IgE binding to hen OM indicated high positive percent. Therefore, from this study, these findings suppose that hen OM is the most important allergen of egg white proteins
The development of HISPEC for Keck and MODHIS for TMT: science cases and predicted sensitivities
HISPEC is a new, high-resolution near-infrared spectrograph being designed
for the W.M. Keck II telescope. By offering single-shot, R=100,000 between 0.98
- 2.5 um, HISPEC will enable spectroscopy of transiting and non-transiting
exoplanets in close orbits, direct high-contrast detection and spectroscopy of
spatially separated substellar companions, and exoplanet dynamical mass and
orbit measurements using precision radial velocity monitoring calibrated with a
suite of state-of-the-art absolute and relative wavelength references. MODHIS
is the counterpart to HISPEC for the Thirty Meter Telescope and is being
developed in parallel with similar scientific goals. In this proceeding, we
provide a brief overview of the current design of both instruments, and the
requirements for the two spectrographs as guided by the scientific goals for
each. We then outline the current science case for HISPEC and MODHIS, with
focuses on the science enabled for exoplanet discovery and characterization. We
also provide updated sensitivity curves for both instruments, in terms of both
signal-to-noise ratio and predicted radial velocity precision.Comment: 25 pages, 9 figures. To appear in the Proceedings of SPIE: Techniques
and Instrumentation for Detection of Exoplanets XI, vol. 12680 (2023
Base-Resolution Methylome of Retinal Pigment Epithelial Cells Used in the First Trial of Human Induced Pluripotent Stem Cell-Based Autologous Transplantation
The first-in-human trial of induced pluripotent stem cell (iPSC)-based autologous transplantation was successfully performed on a female patient with age-related macular degeneration. Here we delineated the base-resolution methylome of the iPSC-derived retinal pigment epithelium (iRPE) used in this trial. The methylome of iRPE closely resembled that of native RPE (nRPE), although partially methylated domains (PMDs) emerged in iRPE but not nRPE. Most differentially methylated regions between iRPE and nRPE appeared to originate from (de)methylation errors during differentiation, whereas errors at reprogramming resulted in aberrant genomic imprinting and X chromosome reactivation. Moreover, non-CpG methylation was prominent in nRPE but not iRPE. Intriguingly, xenotransplantation to mouse remodeled the iRPE methylome to demethylate a subset of suppressed genes and accumulate non-CpG methylation, but failed to resolve PMDs and hypermethylated CpG islands. Although the impacts of these alterations remain elusive, our findings should provide a useful guide for methylome analyses of other iPSC-derived cells
Trail Making Test Part A and Brain Perfusion Imaging in Mild Alzheimer's Disease
Background/Aims: The Trail Making Test (TMT) has long been used to investigate deficits in cognitive processing speed and executive function in humans. However, there are few studies that elucidate the neural substrates of the TMT. The aim of the present study was to identify the regional perfusion patterns of the brain associated with performance on the TMT part A (TMT-A) in patients with Alzheimer's disease (AD). Methods: Eighteen AD patients with poor performance on the TMT-A and 36 age- and sex-matched AD patients with good performance were selected. All subjects underwent brain single photon emission computed tomography. Results: No significant differences between the good and poor performance groups were found with respect to years of education and revised Addenbrooke's Cognitive Examination scores. However, higher z-scores for hypoperfusion in the bilateral superior parietal lobule were observed in the group that scored poorly on the TMT-A compared with the good performance group. Conclusion: Our results suggest that functional activity of the bilateral superior parietal lobules is closely related to performance time on the TMT-A. Thus, the performance time on the TMT-A might be a promising index of dysfunction of the superior parietal area among mild AD patients