82 research outputs found
Toroidal Spiral Nambu-Goto Strings around Higher-Dimensional Black Holes
We present solutions of the Nambu-Goto equation for test strings in a shape
of toroidal spiral in five-dimensional spacetimes. In particular, we show that
stationary toroidal spirals exist around the five-dimensional Myers-Perry black
holes. We also show the existence of innermost stationary toroidal spirals
around the five-dimensional black holes like geodesic particles orbiting around
four-dimensional black holes.Comment: 9 pages, 5 figure
Dynamics of Toroidal Spiral Strings around Five-dimensional Black Holes
We examine the separability of the Nambu-Goto equation for test strings in a
shape of toroidal spiral in a five-dimensional Kerr-AdS black hole. In
particular, for a `{\it Hopf loop}\rq string which is a special class of the
toroidal spiral strings, we show the complete separation of variables occurs in
two cases, Kerr background and Kerr-AdS background with equal angular momenta.
We also obtain the dynamical solution for the Hopf loop around a black hole and
for the general toroidal spiral in Minkowski background.Comment: 16 pages, 1 figure, minor changes, references adde
Identification of novel peptide motifs in the serpin maspin that affect vascular smooth muscle cell function
Maspin is a non-inhibitory member of the serpin family that affects cell behaviours related to migration and survival. We have previously shown that peptides of the isolated G α-helix (G-helix) domain of maspin show bioactivity. Migration, invasion, adhesion and proliferation of vascular smooth muscle cells (VSMC) are important processes that contribute to the build-up of atherosclerotic plaques. Here we report the use of functional assays of these behaviours to investigate whether other maspin-derived peptides impact directly on VSMC; focusing on potential anti-atherogenic properties. We designed 18 new peptides from the structural moieties of maspin above ten amino acid residues in length and considered them beside the existing G-helix peptides. Of the novel peptides screened those with the sequences of maspin strand 4 and 5 of beta sheet B (S4B and S5B) reduced VSMC migration, invasion and proliferation, as well as increasing cell adhesion. A longer peptide combining these consecutive sequences showed a potentiation of responses, and a 7-mer contained all essential elements for functionality. This is the first time that these parts of maspin have been highlighted as having key roles affecting cell function. We present evidence for a mechanism whereby S4B and S5B act through ERK1/2 and AMP-activated protein kinase (AMPK) to influence VSMC responses
Adiponectin receptor-1 expression is associated with good prognosis in gastric cancer
<p>Abstract</p> <p>Background</p> <p>Adiponectin is inversely related to BMI, positively correlates with insulin sensitivity, and has anti-atherogenic effects. In recent years, adiponectin has been well studied in the field of oncology. Adiponectin has been shown to have antiproliferative effects on gastric cancer, and adiponectin expression is inversely correlated with clinical staging of the disease. However, no studies have reported the correlation between serum adiponectin and receptor expression with disease progression.</p> <p>Methods</p> <p>In this study, we evaluated expression levels of 2 adiponectin receptors--AdipoR1 and AdipoR2--and attempted to correlate their expression with prognosis in gastric cancer patients. AdipoR1 and AdipoR2 expression in gastric cancer cell lines (MKN45, TMK-1, NUGC3, and NUGC4) was evaluated by western blotting analysis, and the antiproliferative potential of adiponectin was examined in vitro. Serum adiponectin levels were evaluated in 100 gastric cancer patients, and the expression of AdipoR1 and AdipoR2 was assessed by immunohistochemical staining.</p> <p>Results</p> <p>MKN45 and NUGC3 expressed higher levels of AdipoR1 compared to NUGC4, even though there was no significance in AdipoR2 expression. The antiproliferative effect of adiponectin was confirmed in MKN45 and NUGC3 at 10 μg/ml. No significant associations were observed between serum adiponectin levels and clinicopathological characteristics, but lymphatic metastasis and peritoneal dissemination were significantly higher in the negative AdipoR1 immunostaining group (24/32, <it>p </it>= 0.013 and 9/32, <it>p </it>= 0.042, respectively) compared to the positive AdipoR1 group (lymphatic metastasis, 33/68; peritoneal dissemination, 8/68). On the other hand, AdipoR2 expression was only associated with histopathological type (<it>p </it>= 0.001). In survival analysis, the AdipoR1 positive staining group had significantly longer survival rates than the negative staining group (<it>p </it>= 0.01). However, multivariate analysis indicated that AdipoR1 was not an independent prognostic factor on patient's survival on gastric cancer.</p> <p>Conclusions</p> <p>In gastric cancer, adiponectin has the possibility to be involved in cell growth suppression via AdipoR1. The presence of AdipoR1 could be a novel anticancer therapeutic target in gastric cancer.</p
Classical tests of General Relativity in thick branes
Classical tests of General Relativity in braneworld scenarios have been
investigated recently with the purpose of posing observational constraints on
parameters of some models of infinitely thin brane. Here we consider the motion
of test particles in a thick brane scenario that corresponds to a regularized
version of the Garriga-Tanaka solution, which describes a black hole solution
in RSII model, in the weak field regime. By adapting a mechanism previously
formulated in order to describe the confinement of massive tests particles in a
domain wall (that simulates classically the trapping of the Dirac field in a
domain wall), we study the influence of the brane thickness on the
four-dimensional (4D) path of massless particles. Although the geometry is not
warped and, therefore, the bound motion in the transverse direction is not
decoupled from the movement in the 4D-world, we can find an explicit solution
for the light deflection and the time delay, if the motion in the fifth
direction is a high frequency oscillation. We verify that, owing to the
transverse motion, the light deflection and the time delay depend on the energy
of the light rays. This feature may lead to the phenomenon of gravitational
rainbow. We also consider the problem from a semi-classical perspective,
investigating the effects of the brane thickness on the motion of the zero-mode
in the 4D-world
Exposição humana ao metilmercúrio em comunidades ribeirinhas da Região do Tapajós, Pará, Brasil
Phenomenological studies of the effects of miniaturization and irradiation on the mechanical properties of stainless steels
Adding metoclopramide to paroxetine induced extrapyramidal symptoms and hyperprolactinemia in a depressed woman: a case report
Ryohei Igata, Hikaru Hori, Kiyokazu Atake, Asuka Katsuki, Jun Nakamura Department of Psychiatry, University of Occupational and Environmental Health, Kitakyushu, Japan Abstract: A 54-year-old Japanese woman was diagnosed with major depressive disorder and prescribed paroxetine 20 mg/day. In around May 2013, the patient experienced gastric discomfort, so metoclopramide was prescribed. Beginning on June 4, 2013, the patient was given metoclopramide, 10 mg intravenously, twice per week. On the seventh day after beginning metoclopramide, facial hot flushes, increased sweating, muscle rigidity, and galactorrhea were noted. Extrapyramidal symptoms (EPS) rapidly subsided in response to an intramuscular injection of biperiden. Blood biochemical tests revealed an elevated serum prolactin level of 44 ng/mL. After stopping metoclopramide, EPS disappeared. Serum prolactin level decreased to 15 ng/mL after 4 weeks. In our case, although no adverse reactions had previously occurred following the administration of metoclopramide, the patient developed EPS and hyperprolactinemia following the administration of this antiemetic in combination with paroxetine. Paroxetine and metoclopramide are mainly metabolized by CYP2D6, and they are inhibitors for CYP2D6. We report a case with EPS and hyperprolactinemia whose plasma paroxetine and metoclopramide level rapidly increased after the addition of metoclopramide. Our experience warrants the issuing of a precaution that adverse reactions may arise following the coadministration of metoclopramide and paroxetine even at their respective standard dose levels. Keywords: metoclopramide, paroxetine, extrapyramidal symptoms, SSRI, hyperprolactinemia, depressio
Influence of fluvoxamine on plasma interleukin-6 or clinical improvement in patients with major depressive disorder
Reiji Yoshimura, Asuka Katsuki, Kiyokazu Atake, Hikaru Hori, Ryohei Igata, Yuki KonishiDepartment of Psychiatry, University of Occupational and Environmental Health, Yahatanishi-ku, Kitakyushu, Fukuoka, Japan Objectives: The etiology of depression remains unknown. There is, however, a growing body of evidence that cytokines are involved in the pathophysiology of depression. The aim of this study is to investigate the effects of fluvoxamine on plasma interleukin-6 (IL-6) levels and on clinical improvement of the depressive state.Subjects and methods: Thirty patients who met the DSM-IV criteria for major depressive disorder (MDD) were enrolled in the study. Thirteen were male and 17 were female, and their ages ranged from 26 to 70 years (mean ± standard deviation 45.0±14.2). The patients were treated with fluvoxamine for 8 weeks. The dosages of fluvoxamine varied among the patients and, based on ethical considerations, were not fixed.Results: The fluvoxamine doses were positively related to plasma fluvoxamine levels (r=0.8798, P<0.001). A significant correlation was observed between the patients’ plasma IL-6 levels and their 17-item Hamilton Rating Scale for Depression (HAMD17) scores (r=0.4555, P=0.0010). A positive correlation was found between the delta plasma IL-6 (week 0–week 8) and the delta HAMD17 (week 0–week 8) (r=0.5226, P=0.002).Conclusion: Effect of fluvoxamine on IL-6 is partially associated with its clinical efficacy for MDD. Keywords: fluvoxamine, interleukin, Hamilton Rating Scale for Depression, major depressive disorde
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