346 research outputs found
Instanton dynamics in finite temperature QCD via holography
We investigate instantons in finite temperature QCD via Witten's holographic
QCD. To study the deconfinement phase, we use the setup proposed in [1]
(arXiv:1107.4048). We find that the sizes of the instantons are stabilized at
certain values both in the confinement and deconfinement phases. This agrees
with the numerical result in the lattice gauge theory. Besides we find that the
gravity duals of the large and small instantons in the deconfinement phase have
different topologies. We also argue that the fluctuation of the topological
charges is large in confinement phase while it is exponentially suppressed in
deconfinement phase, and a continuous transition occurs at the
Gross-Witten-Wadia (GWW) point. It would be difficult to observe the
counterpart of this transition in lattice QCD, since the GWW point in QCD may
stay at an unstable branch.Comment: 25 pages, 4 figures; v2: references added, minor correction
Effects of Neonatal Treatment With 6-Hydroxydopamine and Endocrine Disruptors on Motor Activity and Gene Expression in Rats
To investigate the mechanisms underlying
motor hyperactivity, we performed intracisternal
injection of 6-hydroxydopamine or
endocrine disruptors in rats on postnatal day 5.
6-Hydroxydopamine (100 μg, 488 nmol) caused
a significant increase in spontaneous motor
activities at 4 weeks of age. Gene-expression
profiling using a cDNA membrane array
revealed alterations in several classes of gene at
8 weeks of age. In the midbrain, gene expression
was enhanced in dopamine transporter 1; a
platelet-derived growth factor receptor;
dopamine receptor D4; galanin receptor 2;
arginine vasopressin receptor 2; neuropeptide Y;
tachykinin 2; and fibroblast growth factor 10.
Expression was also enhanced in the
glutamate/aspartate transporter gene in the
striatum. Rats received an endocrine disruptor
(87 nmol), such as bisphenol A, nonylphenol, p-octylphenol,
or diethylhexylphthalate, which
also caused motor hyperactivity at 4 weeks.
The effects of bisphenol A on motor activity
were dose-dependent from 0.87 to 87 nmol. The
phenols caused a deficit in dopamine neurons,
similarly to the deficit caused by 6-hydroxydopamine.
Gene-expression profiles after
treatment with endocrine disruptors showed
variation and differed from those of 6-
hydroxydopamine. The results suggest that
neonatal treatment with environmental
chemicals can generate an animal model of
attention-deficit hyperactivity disorder, in
which clinical symptoms are pervasive
Quantitative ultrasonic assessment for detecting microscopic cartilage damage in osteoarthritis
Osteoarthritis (OA) is one of the most prevalent chronic conditions. The histological cartilage changes in OA include surface erosion and irregularities, deep fissures, and alterations in the staining of the matrix. The reversibility of these chondral alterations is still under debate. It is expected that clinical and basic science studies will provide the clinician with new scientific information about the natural history and optimal treatment of OA at an early stage. However, a reliable method for detecting microscopic changes in early OA has not yet been established. We have developed a novel system for evaluating articular cartilage, in which the acoustic properties of the articular cartilage are measured by introducing an ultrasonic probe into the knee joint under arthroscopy. The purpose of this study was to assess microscopic cartilage damage in OA by using this cartilage evaluation system on collagenase-treated articular cartilage in vivo and in vitro. Ultrasonic echoes from articular cartilage were converted into a wavelet map by wavelet transformation. On the wavelet map, the maximum magnitude and echo duration were selected as quantitative indices. Using these indices, the articular cartilage was examined to elucidate the relationships of the ultrasonic analysis with biochemical, biomechanical and histological analyses. In the in vitro study, the maximum magnitude decreased as the duration of collagenase digestion increased. Correlations were observed between the maximum magnitude and the proteoglycan content from biochemical findings, and the maximum magnitude and the aggregate modulus from biomechanical findings. From the histological findings, matrix staining of the surface layer to a depth of 500 μm was closely related to the maximum magnitude. In the in vivo study, the maximum magnitude decreased with increasing duration of the collagenase injection. There was a significant correlation between the maximum magnitude and the aggregate modulus. The evaluation system therefore successfully detected microscopic changes in degenerated cartilage with the use of collagen-induced OA
Extensive Preferential Pathway Ablation for the Elimination of Premature Ventricular Contractions Arising from the Right Ventricular Outflow Tract
AbstractA 76 y/o women presented with 2 different types of premature ventricular contractions (VPCs 1 and 2) arising from the right ventricular outflow tract (RVOT). Catheter ablation (CA) eliminated PVC1 at the earliest activation site (EAS), but thereafter another PVC morphology (PVC3) appeared. Small potentials preceding the local potential were broadly exhibited from the RVOT’s supero-anterior region to the EAS during PVC3. Point CA targeting such prepotentials failed. Transverse-linear CA with a line connecting sites with such pre-potentials eliminated both PVCs 3 and 2. In cases with broadly spreading preferential pathways, extensive CA might be needed to eliminate the PVCs
人工距骨併用の人工足関節置換術
AIMS: Total ankle arthroplasty (TAA) has become the most reliable surgical solution for patients with end-stage arthritis of the ankle. Aseptic loosening of the talar component is the most common complication. A custom-made artificial talus can be used as the talar component in a combined TAA for patients with poor bone stock of the talus. The purpose of this study was to investigate the functional and clinical outcomes of combined TAA. PATIENTS AND METHODS: Ten patients (two men, eight women; ten ankles) treated using a combined TAA between 2009 and 2013 were matched for age, gender, and length of follow-up with 12 patients (one man, 11 women; 12 ankles) who underwent a standard TAA. All had end-stage arthritis of the ankle. The combined TAA features a tibial component of the TNK ankle (Kyocera, Kyoto, Japan) and an alumina ceramic artificial talus (Kyocera), designed using individualized CT data. The mean age at the time of surgery in the combined TAA and standard TAA groups was 71 years (61 to 82) and 75 years (62 to 82), respectively. The mean follow-up was 58 months (43 to 81) and 64 months (48 to 88), respectively. The outcome was assessed using the Japanese Society for Surgery of the Foot (JSSF) ankle-hindfoot scale, the Ankle Osteoarthritis Scale (AOS), and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q). RESULTS: The mean preoperative JSSF score of the combined TAA and standard TAA groups was 44 (sd 11) and 49 (sd 10), respectively. The mean postoperative JSSF scores were 89 (sd 6.1) and 72 (sd 15), respectively. The mean postoperative JSSF score of the combined TAA group was significantly higher (p = 0.0034). The mean preoperative AOS scores for pain and function in the combined TAA and standard TAA groups were 5.8 (sd 3.3) and 5.5 (sd 3.1), and 8.6 (sd 1.3), and 7.1 (sd 2.9), respectively. The mean postoperative AOS scores of pain and function were 2.5 (sd 2.5) and 2.2 (sd 1.9), and 2.5 (sd 3.3) and 3.4 (sd 2.9), respectively. There were no significant differences between the two groups in terms of postoperative AOS scores. The mean postoperative SAFE-Q scores were: for pain, 76 (sd 23) and 70 (sd 23); for physical function, 66 (sd 25) and 55 (sd 27); for social function, 73 (sd 35) and 62 (sd 34); for shoe-related, 73 (sd 19) and 65 (sd 26); and for general health, 78 (sd 28) and 67 (sd 29), respectively. There were no significant differences between the two groups in terms of postoperative SAFE-Q scores. CONCLUSION: Combined TAA resulted in better clinical results than standard TAA. Cite this article: Bone Joint J 2019;101-B:443-446.博士(医学)・甲第717号・令和元年6月26日This is a non-final version of an article published in final form in "http://dx.doi.org/10.1302/0301-620X.101B4.BJJ-2018-0812.R2
Involvement of the leaf-specific multidrug and toxic compound extrusion (MATE) transporter Nt-JAT2 in vacuolar sequestration of nicotine in Nicotiana tabacum
Alkaloids play a key role in higher plant defense against pathogens and herbivores. Following its biosynthesis in root tissues, nicotine, the major alkaloid of Nicotiana species, is translocated via xylem transport toward the accumulation sites, leaf vacuoles. Our transcriptome analysis of methyl jasmonate-treated tobacco BY-2 cells identified several multidrug and toxic compound extrusion (MATE) transporter genes. In this study, we characterized a MATE gene, Nicotiana tabacum jasmonate-inducible alkaloid transporter 2 (Nt-JAT2), which encodes a protein that has 32% amino acid identity with Nt-JAT1. Nt-JAT2 mRNA is expressed at a very low steady state level in whole plants, but is rapidly upregulated by methyl jasmonate treatment in a leaf-specific manner. To characterize the function of Nt-JAT2, yeast cells were used as the host organism in a cellular transport assay. Nt-JAT2 was localized at the plasma membrane in yeast cells. When incubated in nicotine-containing medium, the nicotine content in Nt-JAT2-expressing cells was significantly lower than in control yeast. Nt-JAT2-expressing cells also showed lower content of other alkaloids like anabasine and anatabine, but not of flavonoids, suggesting that Nt-JAT2 transports various alkaloids including nicotine. Fluorescence assays in BY-2 cells showed that Nt-JAT2-GFP was localized to the tonoplast. These findings indicate that Nt-JAT2 is involved in nicotine sequestration in leaf vacuoles following the translocation of nicotine from root tissues
Emission spectra and invariant masses of Lambda and p in the stopped-K-NN absorption process in 4He and 6Li
We have calculated the emission spectra of Y and N and invariant masses of YN
pairs in the direct K-NN --> YN absorption process at rest in 4He and light
nuclei in order to provide theoretical tools for correct interpretations of
experimental data with or without invoking kaonic nuclear bound states. All the
momentum distributions are broad with widths around 150-200 MeV/c (except for
the case of 6Li target), while the partial invariant mass of each YN pair has a
peak around 2310-2330 MeV/c2. We argue against the interpretations of
stopped-K- experimental data of KEK and FINUDA by Oset and Toki and by Magas,
Oset, Ramos and Toki.Comment: 29 pages, 15 figure
Kaempulchraols IO: new isopimarane diterpenoids from Kaempferia pulchra rhizomes collected in Myanmar and their antiproliferative activity
The isolation of the CHCl3 soluble extract of Kaempferia pulchra rhizomes afforded seven new isopimarane diterpenoids, kaempulchraols I−O, together with one known analogue. The structures of these compounds were elucidated using 1D and 2D NMR and X-ray diffraction analyses. The antiproliferative activity of the isolated compounds was evaluated against a panel of five human cancer cell lines. Kaempulchraol L exhibited weak antiproliferative activity against PANC-1 and PSN-1 cells with IC50 values of 39.9 and 22.6 μM, respectively
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