135 research outputs found
The potential of the antiplatelet agent ticagrelor as a new antibacterial agent
The number of deaths caused by drug-resistant bacteria is expected to increase in the future, and there is a need to develop new antimicrobial agents. Recently, the antiplatelet drug ticagrelor has been reported to have promising antibacterial properties. The purpose of this review is to analyze articles and case reports that describe the antimicrobial action of ticagrelor. Ticagrelor was found to have antibacterial reactions against Gram-positive bacteria, including drug-resistant and spore-forming bacteria, while no effect was observed against Gram-negative bacteria. In this paper we discuss a new potential antimicrobial agent, ticagrelor.The number of deaths caused by drug-resistant bacteria is expected to increase in the future, and there is a need to develop new antimicrobial agents. Recently, the antiplatelet drug ticagrelor has been reported to have promising antibacterial properties. The purpose of this review is to analyze articles and case reports that describe the antimicrobial action of ticagrelor. Ticagrelor was found to have antibacterial reactions against Gram-positive bacteria, including drug-resistant and spore-forming bacteria, while no effect was observed against Gram-negative bacteria. In this paper we discuss a new potential antimicrobial agent, ticagrelor
The potential of the antiplatelet agent ticagrelor as a new antibacterial agent
The number of deaths caused by drug-resistant bacteria is expected to increase in the future, and there is a need to develop new antimicrobial agents. Recently, the antiplatelet drug ticagrelor has been reported to have promising antibacterial properties. The purpose of this review is to analyze articles and case reports that describe the antimicrobial action of ticagrelor. Ticagrelor was found to have antibacterial reactions against Gram-positive bacteria, including drug-resistant and spore-forming bacteria, while no effect was observed against Gram-negative bacteria. In this paper we discuss a new potential antimicrobial agent, ticagrelor.The number of deaths caused by drug-resistant bacteria is expected to increase in the future, and there is a need to develop new antimicrobial agents. Recently, the antiplatelet drug ticagrelor has been reported to have promising antibacterial properties. The purpose of this review is to analyze articles and case reports that describe the antimicrobial action of ticagrelor. Ticagrelor was found to have antibacterial reactions against Gram-positive bacteria, including drug-resistant and spore-forming bacteria, while no effect was observed against Gram-negative bacteria. In this paper we discuss a new potential antimicrobial agent, ticagrelor
Stability of ferromagnetism in the Hubbard model on the kagom\'e lattice
The Hubbard model on the kagom\'e lattice has highly degenerate ground states
(the flat lowest band) in the corresponding single-electron problem and
exhibits the so-called flat-band ferromagnetism in the many-electron ground
states as was found by Mielke. Here we study the model obtained by adding extra
hopping terms to the above model. The lowest single-electron band becomes
dispersive, and there is no band gap between the lowest band and the other
band. We prove that, at half-filling of the lowest band, the ground states of
this perturbed model remain saturated ferromagnetic if the lowest band is
nearly flat.Comment: 4 pages, 1 figur
Fe-K line probing of material around the AGN central engine with Suzaku
We systematically analyzed the high-quality Suzaku data of 88 Seyfert
galaxies. We obtained a clear relation between the absorption column density
and the equivalent width of the 6.4 keV line above 10 cm,
suggesting a wide-ranging column density of cm with a
similar solid and a Fe abundance of 0.7--1.3 solar for Seyfert 2 galaxies. The
EW of the 6.4 keV line for Seyfert 1 galaxies are typically 40--120 eV,
suggesting the existence of Compton-thick matter like the torus with a column
density of cm and a solid angle of , and no
difference of neutral matter is visible between Seyfert 1 and 2 galaxies. An
absorber with a lower column density of cm for Compton-thin
Seyfert 2 galaxies is suggested to be not a torus but an interstellar medium.
These constraints can be understood by the fact that the 6.4 keV line intensity
ratio against the 10--50 keV flux is almost identical within a range of 2--3 in
many Seyfert galaxies. Interestingly, objects exist with a low EW, 10--30 eV,
of the 6.4 keV line, suggesting that those torus subtends only a small solid
angle of . Ionized Fe-K emission or absorption lines are
detected from several percents of AGNs. Considering the ionization state and
equivalent width, emitters and absorbers of ionized Fe-K lines can be explained
by the same origin, and highly ionized matter is located at the broad line
region. The rapid increase in EW of the ionized Fe-K emission lines at
cm is found, like that of the cold material. It is found
that these features seem to change for brighter objects with more than several
erg/s such that the Fe-K line features become weak. We discuss this
feature, together with the torus structure.Comment: 32 pages, 20 figures, ApJ accepte
X-Ray and Near-Infrared Observations of GX 339-4 in the Low/Hard State with Suzaku and IRSF
X-ray and near-infrared (--) observations of the Galactic
black hole binary GX 339--4 in the low/hard state were performed with Suzaku
and IRSF in 2009 March. The spectrum in the 0.5--300 keV band is dominated by
thermal Comptonization of multicolor disk photons, with a small contribution
from a direct disk component, indicating that the inner disk is almost fully
covered by hot corona with an electron temperature of 175 keV. The
Comptonizing corona has at least two optical depths, .
Analysis of the iron-K line profile yields an inner disk radius of
( represents the gravitational
radius ), with the best-fit inclination angle of .
This radius is consistent with that estimated from the continuum fit by
assuming the conservation of photon numbers in Comptonization. Our results
suggest that the standard disk of GX 339--4 is likely truncated before reaching
the innermost stable circular orbit (for a non rotating black hole) in the
low/hard state at 1% of the Eddington luminosity. The one-day averaged
near-infrared light curves are found to be correlated with hard X-ray flux with
. The flatter near infrared
spectrum than the radio one suggests that the optically thin synchrotron
radiation from the compact jets dominates the near-infrared flux. Based on a
simple analysis, we estimate the magnetic field and size of the jet base to be
G and cm, respectively. The synchrotron self
Compton component is estimated to be approximately 0.4% of the total X-ray
flux.Comment: 17pages, 15 figures, accepted for publication in PASJ (Suzaku and
MAXI Special Issue
The 2006 November outburst of EG Aquarii: the SU UMa nature revealed
We report time-resolved CCD photometry of the cataclysmic variable EG Aquarii
during the 2006 November outburst During the outburst, superhumps were
unambiguously detected with a mean period of 0.078828(6) days, firstly
classifying the object as an SU UMa-type dwarf nova. It also turned out that
the outburst contained a precursor. At the end of the precursor, immature
profiles of humps were observed. By a phase analysis of these humps, we
interpreted the features as superhumps. This is the second example that the
superhumps were shown during a precursor. Near the maximum stage of the
outburst, we discovered an abrupt shift of the superhump period by
0.002 days. After the supermaximum, the superhump period decreased at the rate
of =, which is typical for SU UMa-type dwarf
novae. Although the outburst light curve was characteristic of SU UMa-type
dwarf novae, long-term monitoring of the variable shows no outbursts over the
past decade. We note on the basic properties of long period and inactive SU
UMa-type dwarf novae.Comment: 9 pages, 7 figures, accepted for PAS
High-level expression by tissue/cancer-specific promoter with strict specificity using a single-adenoviral vector
Tissue-/cancer-specific promoters for use in adenovirus vectors (AdVs) are valuable for elucidating specific gene functions and for use in gene therapy. However, low activity, non-specific expression and size limitations in the vector are always problems. Here, we developed a ‘double-unit’ AdV containing the Cre gene under the control of an α-fetoprotein promoter near the right end of its genome and bearing a compact ‘excisional-expression’ unit consisting of a target cDNA ‘upstream’ of a potent promoter between two loxPs near the left end of its genome. When Cre was expressed, the expression unit was excised as a circular molecule and strongly expressed. Undesired leak expression of Cre during virus preparation was completely suppressed by a dominant-negative Cre and a short-hairpin RNA against Cre. Using this novel construct, a very strict specificity was maintained while achieving a 40- to 90-fold higher expression level, compared with that attainable using a direct specific promoter. Therefore, the ‘double-unit’ AdV enabled us to produce a tissue-/cancer-specific promoter in an AdV with a high expression level and strict specificity
Nuclear spin-lattice relaxation in ferrimagnetic clusters and chains: A contrast between zero and one dimensions
Motivated by ferrimagnetic oligonuclear and chain compounds synthesized by
Caneschi et al., both of which consist of alternating manganese(II) ions and
nitronyl-nitroxide radicals, we calculate the nuclear spin-lattice relaxation
rate 1/T_1 employing a recently developed modified spin-wave theory. 1/T_1 as a
function of temperature drastically varies with the location of probe nuclei in
both clusters and chains, though the relaxation time scale is much larger in
zero dimension than in one dimension. 1/T_1 as a function of an applied field
in long chains forms a striking contrast to that in finite clusters, diverging
with decreasing field like inverse square root at low temperatures and
logarithmically at high temperatures.Comment: to be published in Phys. Rev. B 68 August 01 (2003
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