231 research outputs found
A Case Report of Atypical Spindle Cell Lipomatous Tumor of the Tongue
Herein, we report a case of atypical spindle cell lipomatous tumor (ASCLT) on both sides of the tongue in a 74-year-old male patient. The patient was referred to our department for treatment of the masses in the tongue. Several elastic soft indolent masses were detected during the first examination. The masses were well defined, and their consistency was similar to that of adipose tissues. No signs of induration were observed in the surrounding tissues. The patient was not aware of the masses, which were only detected during his visit at the dental clinic that referred him to our institution. Thus, the onset of the masses remains unknown. ASCLT was identified via histopathological examination. Then, tumor excision was performed under general anesthesia. Thirteen months after surgery, the condition of the patient was good, and signs of local recurrence or postoperative metastasis were not observed
Possible induction by blood transfusion of immunological tolerance against growth of transplanted tumors in mice.
That blood transfusions aid kidney graft survival is well known. Our data show that blood transfusions, except for the red blood cell component, promote growth of transplanted tumors in mice. These clinical and experimental observations suggest that blood transfusions may induce some immunological tolerance.</p
Surrogate marker of schistocytes
Objectives : Hematopoietic stem cell transplantation (HSCT)-associated thrombotic microangiopathy (TA-TMA) is an important early post-treatment condition. This study evaluated the Revised %MICRO, a parameter obtained from the ADVIA 2120i automated blood cell counter, as a surrogate marker of the schistocyte ratio. We hypothesized that individual differences between the %MICRO value and schistocyte ratio would remain constant. Design and Methods: EDTA-2K-treated peripheral blood samples were collected from 19 patients who underwent allogeneic HSCT from April 2014 to September 2018. First, the baseline difference, X, was calculated using a sample from the first day after HSCT as X = %MICRO (first day) – schistocyte ratio (first day). Next, the Revised %MICRO for each subsequent day was calculated as Revised %MICRO = %MICRO – X. We evaluated correlations of the schistocyte ratio with the calculated %MICRO and Revised %MICRO and the RBC fragment, RBC distribution width, %MICRO and Revised %MICRO data obtained from the ADVIA 2120i. Results : The mean schistocyte percentage and Revised %MICRO were both 0.4% ± 0.6. RBC fragments correlated weakly with the %MICRO and schistocyte ratio, respectively (r = 0.162 and r = 0.771, respectively), whereas the Revised %MICRO correlated strongly with the schistocyte ratio (r = 0.893). Conclusion : The Revised %MICRO appears to be a good surrogate of the schistocyte ratio in a clinical setting
Suzaku Observations of SGR 1900+14 and SGR 1806-20
Spectral and timing studies of Suzaku ToO observations of two SGRs, 1900+14
and 1806-20, are presented. The X-ray quiescent emission spectra were well
fitted by a two blackbody function or a blackbody plus a power law model. The
non-thermal hard component discovered by INTEGRAL was detected by the PIN
diodes and its spectrum was reproduced by the power law model reported by
INTEGRAL. The XIS detected periodicity P = 5.1998+/-0.0002 s for SGR 1900+14
and P = 7.6022+/-0.0007 s for SGR 1806-20. The pulsed fraction was related to
the burst activity for SGR 1900+14.Comment: 8 pages, 3 figures, Accepted for publication in PASJ (Suzaku 3rd
special issue
Outburst of LS V+44 17 Observed by MAXI and RXTE, and Discovery of a Dip Structure in the Pulse Profile
We report on the first observation of an X-ray outburst of a Be/X-ray binary
pulsar LS V +44 17/RX J0440.9+4431, and the discovery of an absorption dip
structure in the pulse profile. An outburst of this source was discovered by
MAXI GSC in 2010 April. It was the first detection of the transient activity of
LS V +44 17 since the source was identified as a Be/X-ray binary in 1997. From
the data of the follow-up RXTE observation near the peak of the outburst, we
found a narrow dip structure in its pulse profile which was clearer in the
lower energy bands. The pulse-phase-averaged energy spectra in the 3100 keV
band can be fitted with a continuum model containing a power-law function with
an exponential cutoff and a blackbody component, which are modified at low
energy by an absorption component. A weak iron K emission line is also
detected in the spectra. From the pulse-phase-resolved spectroscopy we found
that the absorption column density at the dip phase was much higher than those
in the other phases. The dip was not seen in the subsequent RXTE observations
at lower flux levels. These results suggest that the dip in the pulse profile
originates from the eclipse of the radiation from the neutron star by the
accretion column.Comment: 18 pages, 7 figures, accepted for publication in PAS
Validation studies of gyrokinetic ITG and TEM turbulence simulations in a JT-60U tokamak using multiple flux matching
Quantitative validation studies of flux-tube gyrokinetic Vlasov simulations on ion and electronheat transport are carried out for the JT-60U tokamak experiment. The ion temperaturegradient (ITG) and/or trapped electron modes (TEM) driven turbulent transport and zonalflow generations are investigated for an L-mode plasma in the local turbulence limit with asufficiently small normalized ion thermal gyroradius and weak mean radial electric fields.Nonlinear turbulence simulations by the GKV code successfully reproduce radial profilesof the ion and electron energy fluxes in the core region. The numerical results show that theTEM-driven zonal flow generation in the outer region is more significant than that in the coreregion with ITG- and ITG–TEM-dominated turbulence, leading to moderate transport shortfallof the ion energy flux. Error levels in the prediction of the ion and electron temperaturegradient profiles in the core region are estimated as less than ±30%, based on a multiple fluxmatching technique, where the simulated ion and electron energy fluxes are simultaneouslymatched to the experimental values
MAXI GSC observations of a spectral state transition in the black hole candidate XTE J1752-223
We present the first results on the black hole candidate XTE J1752-223 from
the Gas Slit Camera (GSC) on-board the Monitor of All-sky X-ray Image (MAXI) on
the International Space Station. Including the onset of the outburst reported
by the Proportional Counter Array on-board the Rossi X-ray Timing Explorer on
2009 October 23, the MAXI/GSC has been monitoring this source approximately 10
times per day with a high sensitivity in the 2-20 keV band. XTE J1752-223 was
initially in the low/hard state during the first 3 months. An anti-correlated
behavior between the 2-4 keV and 4-20 keV bands were observed around January
20, 2010, indicating that the source exhibited the spectral transition to the
high/soft state. A transient radio jet may have been ejected when the source
was in the intermediate state where the spectrum was roughly explained by a
power-law with a photon index of 2.5-3.0. The unusually long period in the
initial low/hard state implies a slow variation in the mass accretion rate, and
the dramatic soft X-ray increase may be explained by a sudden appearance of the
accretion disk component with a relatively low innermost temperature (0.4-0.7
keV). Such a low temperature might suggest that the maximum accretion rate was
just above the critical gas evaporation rate required for the state transition.Comment: Publication of Astronomical Society of Japan Vol.62, No.5 (2010) [in
print
Bright X-ray flares from the BL Lac object Mrk 421, detected with MAXI in 2010 January and February
Strong X-ray flares from the blazar Mrk 421 were detected in 2010 January and
February through the 7 month monitoring with the MAXI GSC. The maximum 2 -- 10
keV flux in the January and February flares was measured as 120 +- 10 mCrab and
164 +- 17 mCrab respectively; the latter is the highest among those reported
from the object. A comparison of the MAXI and Swift BAT data suggests a convex
X-ray spectrum with an approximated photon index of about 2. This spectrum is
consistent with a picture that MAXI is observing near the synchrotron peak
frequency. The source exhibited a spectral variation during these flares,
slightly different from those in the previous observations, in which the
positive correlation between the flux and hardness was widely reported. By
equating the halving decay timescale in the January flare, s, to the synchrotron cooling time, the magnetic field was
evaluated as B = 0.045 G , where is the jet
beaming factor. Assuming that the light crossing time of the emission region is
shorter than the doubling rise time, s,
the region size was roughly estimated as cm
. These are consistent with the values previously reported. For
the February flare, the rise time, s, gives a
loose upper limit on the size as cm ,
although the longer decay time s, indicates
B = 0.015 G , which is weaker than the previous results.
This could be reconciled by invoking a scenario that this flare is a
superposition of unresolved events with a shorter timescale.Comment: 14 pages, 4 figures, accepted for PASJ (Vol. 62 No. 6
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