118 research outputs found
Covered self-expandable metal stents for distal biliary obstruction from pancreatic carcinoma: what type of stent is preferred?
Preliminary studies on carbon and nitrogen stable isotope ratios analysis of food web in Lake Chany of Western Siberia
Lake Chany is an inland moderately saline lake in Western Siberia. Itconsists of three lakes, Bolshye (Large) Chany, Malye (Small) Chany and Yarkul Pool. Field survey of Lake Chany was carried out at four parts of the lake with different salinity to analyze their food web structures using carbon and nitrogen stable isotope as natusral tracers. The intruding river rigion (St.1) and Malye Chany (St.2) wwkth low salinity (0.9%), the central part of Bolshye Chany (St.3) with salinity of 5.7% and the innermost part of Bolshye Chany (St.4) with the highest salinnity of 6.3% were selected as study sites. Comparison of the isotope ratios of benthis incertebrate (Chironomidae; Diptera) among the sampling sites showed the lowest δ13C and δ15N values at St.1 and highest values at St.4. The benthic invertebrates at St.3 showed similar δ13C and δ15N values to those of St.4 and St.1, respectively. Similar trends but different values of the isotope raions among the sampling stations were observed in zooplankton, POM and sediment samples, indicationg the initial substances of the food chains were different at different parts of the lake.Article信州大学山地水環境教育研究センター研究報告 2: 21-24(2004)departmental bulletin pape
Isotopic evidence for the spatial heterogeneity of the planktonic food webs in the transition zone between river and lake ecosystems
Resources and organisms in food webs are distributed patchily. The spatial structure of food webs is important and critical to understanding their overall structure. However, there is little available information about the small-scale spatial structure of food webs. We investigated the spatial structure of food webs in a lake ecosystem at the littoral transition zone between an inflowing river and a lake. We measured the carbon isotope ratios of zooplankton and particulate organic matter (POM; predominantly phytoplankton) in the littoral zone of a saline lake. Parallel changes in the δ 13C values of zooplankton and their respective POMs indicated that there is spatial heterogeneity of the food web in this study area. Lake ecosystems are usually classified at the landscape level as either pelagic or littoral habitats. However, we showed small-scale spatial heterogeneity among planktonic food webs along an environmental gradient. Stable isotope data is useful for detecting spatial heterogeneity of habitats, populations, communities, and ecosystems
頭頸部癌細胞におけるレスベラトロールのREG III発現誘導効果と癌の進展抑制・治療向上効果
Identification of reliable markers of chemo- and radiosensitivity and the key molecules that enhance the susceptibility of head and neck squamous cell carcinoma (HNSCC) to anticancer treatments is highly desirable. Previously, we have reported that regenerating gene (REG) Ⅲ expression was such a marker associated with an improved survival rate for HNSCC patients. In the present study, we investigated the stimulators for induction of REG Ⅲ expression using REG Ⅲ promoter assay in HNSCC cells transfected with REG Ⅲ promoter vector. We tested inflammatory cytokines, growth factors, polyphenols, PPARγ activator of thiazolidinediones, and histone deacetylase inhibitors, and found that 3,4',5-trihydroxy-trans-stilbene (resveratrol) significantly increased the REG Ⅲ promoter activity and the mRNA levels of REG Ⅲ in HNSCC cells. Moreover, we demonstrated the effect of resveratrol on cancer cell progression, such as cell proliferation, chemo‑ and radiosensitivity and cancer invasion of HNSCC cells. Resveratrol significantly inhibited cell growth, enhanced chemo‑ and radiosensitivity, and blocked cancer invasion of HNSCC cells. These data suggested that resveratrol could inhibit cancer progression through the REG Ⅲ expression pathway in HNSCC cells.博士(医学)・甲第682号・平成30年3月15日Copyright © Spandidos Publications 2017. All rights reserved.The Spandidos Publications link is available at " https://doi.org/10.3892/ijo.2016.3664
Natural Variation in the Flag Leaf Morphology of Rice Due to a Mutation of the NARROW LEAF 1 Gene in Oryza sativa L.
We investigated the natural variations in the flag leaf morphology of rice. We conducted a principal component analysis based on nine flag leaf morphology traits using 103 accessions from the National Institute of Agrobiological Sciences Core Collection. The first component explained 39% of total variance, and the variable with highest loading was the width of the flag leaf (WFL). A genome-wide association analysis of 102 diverse Japanese accessions revealed that marker RM6992 on chromosome 4 was highly associated with WFL. In analyses of progenies derived from a cross between Takanari and Akenohoshi, the most significant quantitative trait locus (QTL) for WFL was in a 10.3-kb region containing the NARROW LEAF 1 (NAL1) gene, located 0.4 Mb downstream of RM6992. Analyses of chromosomal segment substitution lines indicated that a mutation (G1509A single-nucleotide mutation, causing an R233H amino acid substitution in NAL1) was present at the QTL. This explained 13 and 20% of total variability in WFL and the distance between small vascular bundles, respectively. The mutation apparently occurred during rice domestication and spread into japonica, tropical japonica, and indica subgroups. Notably, one accession, Phulba, had a NAL1 allele encoding only the N-terminal, or one-fourth, of the wild-type peptide. Given that the Phulba allele and the histidine-type allele showed essentially the same phenotype, the histidine-type allele was regarded as malfunctional. The phenotypes of transgenic plants varied depending on the ratio of histidine-type alleles to arginine-type alleles, raising the possibility that H(233)-type products function differently from and compete with R(233)-type products
Structures and mechanisms of actin ATP hydrolysis
The major cytoskeleton protein actin undergoes cyclic transitions between the monomeric G-form and the filamentous F-form, which drive organelle transport and cell motility. This mechanical work is driven by the ATPase activity at the catalytic site in the F-form. For deeper understanding of the actin cellular functions, the reaction mechanism must be elucidated. Here, we show that a single actin molecule is trapped in the F-form by fragmin domain-1 binding and present their crystal structures in the ATP analog-, ADP-Pi-, and ADP-bound forms, at 1.15-Å resolutions. The G-to-F conformational transition shifts the side chains of Gln137 and His161, which relocate four water molecules including W1 (attacking water) and W2 (helping water) to facilitate the hydrolysis. By applying quantum mechanics/molecular mechanics calculations to the structures, we have revealed a consistent and comprehensive reaction path of ATP hydrolysis by the F-form actin. The reaction path consists of four steps: 1) W1 and W2 rotations; 2) PG–O3B bond cleavage; 3) four concomitant events: W1–PO3− formation, OH− and proton cleavage, nucleophilic attack by the OH− against PG, and the abstracted proton transfer; and 4) proton relocation that stabilizes the ADP-Pi–bound F-form actin. The mechanism explains the slow rate of ATP hydrolysis by actin and the irreversibility of the hydrolysis reaction. While the catalytic strategy of actin ATP hydrolysis is essentially the same as those of motor proteins like myosin, the process after the hydrolysis is distinct and discussed in terms of Pi release, F-form destabilization, and global conformational changes
Optical IFU Observations of GOALS Sample with KOOLS-IFU on Seimei Telescope: Initial results of 9 U/LIRGs at 0.04
We present ionized gas properties of 9 local ultra/luminous infrared galaxies
(U/LIRGs) at 0.04 through IFU observations with KOOLS-IFU on Seimei
Telescope. The observed targets are drawn from the Great Observatories All-sky
LIRG Survey (GOALS), covering a wide range of merger stages. We successfully
detect emission lines such as H, [OIII]5007, H,
[NII]6549,6583, and [SII]6717,6731 with a
spectral resolution of = 1500-2000, which provides (i) spatially-resolved
(200-700 pc) moment map of ionized gas and (ii) diagnostics for active
galactic nucleus (AGN) within the central 3--11 kpc in diameter for our
sample. We find that [OIII] outflow that is expected to be driven by AGN tends
to be stronger (i) towards the galactic center and (ii) as a sequence of merger
stage. In particular, the outflow strength in the late-stage (stage D) mergers
is about 1.5 times stronger than that in the early-state (stage B) mergers,
which indicates that galaxy mergers could induce AGN-driven outflow and play an
important role in the co-evolution of galaxies and supermassive black holes.Comment: 12 pages, 8 figures, and 2 tables, accepted for publication in PAS
Increased interferon alpha receptor 2 mRNA levels is associated with renal cell carcinoma metastasis
<p>Abstract</p> <p>Background</p> <p>Interferon-α (IFN-α) is one of the central agents in immunotherapy for renal cell carcinoma (RCC) and binds to the IFN-α receptor (IFNAR). We investigated the role of IFNAR in RCC.</p> <p>Methods</p> <p>We quantified IFNAR mRNA expression in paired tumor and non-tumor samples from the surgical specimens of 103 consecutive patients with RCC using a real-time reverse transcription polymerase chain reaction (RT-PCR), and IFNAR2 protein using Western blotting.</p> <p>Results</p> <p>The absolute level of IFNAR1 and IFNAR2 mRNAs in tumor and non-tumor tissues did not correlate with the malignant and metastatic profiles. The relative yields of the PCR product from the tumor tissue to that from the corresponding non-tumor tissue (T/N) for the expression of IFNAR mRNAs were calculated. While the T/N ratio of IFNAR1 did not correlate with any factor, a high T/N ratio of IFNAR2 correlated with poor differentiation (<it>P </it>< 0.05), local invasion (<it>P </it>< 0.001), and metastasis (<it>P </it>< 0.0001). By multivariate analysis, a high T/N ratio of IFNAR2 predicted a shortened overall survival in all cases (<it>P </it>< 0.05) and a shorter disease-free survival in those without metastasis (M0; 68 cases, <it>P </it>< 0.05). Impressively, patients with a poorer response to IFN-α treatment had a higher IFNAR2 T/N ratio than those who had a good response (P < 0.05). IFNAR2c protein expression was higher in the primary tumors in patients with metastases (M1; 35 cases) compared to those without ( P < 0.0001).</p> <p>Conclusion</p> <p>IFNAR2 is associated with the progression of RCC.</p
The ASTRO-H X-ray Observatory
The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly
successful X-ray missions initiated by the Institute of Space and Astronautical
Science (ISAS). ASTRO-H will investigate the physics of the high-energy
universe via a suite of four instruments, covering a very wide energy range,
from 0.3 keV to 600 keV. These instruments include a high-resolution,
high-throughput spectrometer sensitive over 0.3-2 keV with high spectral
resolution of Delta E < 7 eV, enabled by a micro-calorimeter array located in
the focal plane of thin-foil X-ray optics; hard X-ray imaging spectrometers
covering 5-80 keV, located in the focal plane of multilayer-coated, focusing
hard X-ray mirrors; a wide-field imaging spectrometer sensitive over 0.4-12
keV, with an X-ray CCD camera in the focal plane of a soft X-ray telescope; and
a non-focusing Compton-camera type soft gamma-ray detector, sensitive in the
40-600 keV band. The simultaneous broad bandpass, coupled with high spectral
resolution, will enable the pursuit of a wide variety of important science
themes.Comment: 22 pages, 17 figures, Proceedings of the SPIE Astronomical
Instrumentation "Space Telescopes and Instrumentation 2012: Ultraviolet to
Gamma Ray
The Quiescent Intracluster Medium in the Core of the Perseus Cluster
Clusters of galaxies are the most massive gravitationally-bound objects in
the Universe and are still forming. They are thus important probes of
cosmological parameters and a host of astrophysical processes. Knowledge of the
dynamics of the pervasive hot gas, which dominates in mass over stars in a
cluster, is a crucial missing ingredient. It can enable new insights into
mechanical energy injection by the central supermassive black hole and the use
of hydrostatic equilibrium for the determination of cluster masses. X-rays from
the core of the Perseus cluster are emitted by the 50 million K diffuse hot
plasma filling its gravitational potential well. The Active Galactic Nucleus of
the central galaxy NGC1275 is pumping jetted energy into the surrounding
intracluster medium, creating buoyant bubbles filled with relativistic plasma.
These likely induce motions in the intracluster medium and heat the inner gas
preventing runaway radiative cooling; a process known as Active Galactic
Nucleus Feedback. Here we report on Hitomi X-ray observations of the Perseus
cluster core, which reveal a remarkably quiescent atmosphere where the gas has
a line-of-sight velocity dispersion of 164+/-10 km/s in a region 30-60 kpc from
the central nucleus. A gradient in the line-of-sight velocity of 150+/-70 km/s
is found across the 60 kpc image of the cluster core. Turbulent pressure
support in the gas is 4% or less of the thermodynamic pressure, with large
scale shear at most doubling that estimate. We infer that total cluster masses
determined from hydrostatic equilibrium in the central regions need little
correction for turbulent pressure.Comment: 31 pages, 11 Figs, published in Nature July
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