45 research outputs found
Dynamic left ventricular outflow tract obstruction in living donor liver transplantation recipients -A report of two cases-
We present two cases of dynamic left ventricular outflow tract obstruction in 2 patients who were undergoing living donor liver transplantation. On the preoperative transthoracic echocardiography, the first patient showed normal ventricular function and a normal wall thickness, but severe hemodynamic deterioration developed during the anhepatic period and this was further aggravated after reperfusion in spite of volume resuscitation and catecholamine therapy. Intraoperative transesophageal echocardiography revealed the systolic anterior motion of the mitral valve leaflet together with left ventricular outflow tract obstruction. The second patient showed left ventricular hypertrophy with left ventricular outflow tract obstruction on the preoperative echocardiography. Intraoperative transesophageal echocardiography was used to guide fluid administration and the hemodynamic management throughout the procedure and a temporary portocaval shunt was established to mitigate the venous pooling during the anhepatic period. The purpose of this report is to emphasize the clinical significance of dynamic left ventricular outflow tract obstruction in patients who are undergoing living donor liver transplantation and the role of intraoperative echocardiography to detect and manage it
Validity of the Buttoning Test in Hand Disability Evaluation of Patients With Stroke
ObjectiveTo investigate the relationship between the buttoning test and Jebsen-Taylor Hand Function Test (JTHFT), and to determine the validity of using the buttoning test as a tool to evaluate hand disability in patients with stroke.MethodsThis was a retrospective study of the medical records of 151 ischemic stroke patients affecting the dominant hand. Patients underwent the buttoning test and JTHFT for their affected hand. All patients were divided into three groups depending on how quickly they fastened a button (group A, not completed; group B, slowly completed over 18 seconds; and group C, completed within 18 seconds).ResultsThe button fastening time was negatively correlated with the total score and subtest scores of the JTHFT. Patients who experienced difficulty during the buttoning test had lower mean scores in the JTHFT (group A, 28.0±23.9; group B, 62.9±21.7; group C, 75.4±13.3; p<0.0001, Jonckheere-Terpstra test). We observed significant differences in JTHFT scores among the three groups (p<0.017, Mann-Whitney U-test), although there were considerable overlaps in JTHFT scores between the groups. Significant differences were also found in the subtest scores of the JTHFT, which include fine hand motor function (writing letters, p=0.009; moving small objects, p=0.003; stacking checkers, p=0.001 between groups B and C), among the three groups.ConclusionConsidering its relationship with the JTHFT and validity, the buttoning test can be considered appropriate for evaluation of hand disability in patients with stroke
Pilot KaVA monitoring on the M87 jet: confirming the inner jet structure and superluminal motions at sub-pc scales
We report the initial results of our high-cadence monitoring program on the
radio jet in the active galaxy M87, obtained by the KVN and VERA Array (KaVA)
at 22 GHz. This is a pilot study that preceded a larger KaVA-M87 monitoring
program, which is currently ongoing. The pilot monitoring was mostly performed
every two to three weeks from December 2013 to June 2014, at a recording rate
of 1 Gbps, obtaining the data for a total of 10 epochs. We successfully
obtained a sequence of good quality radio maps that revealed the rich structure
of this jet from <~1 mas to 20 mas, corresponding to physical scales
(projected) of ~0.1-2 pc (or ~140-2800 Schwarzschild radii). We detected
superluminal motions at these scales, together with a trend of gradual
acceleration. The first evidence for such fast motions and acceleration near
the jet base were obtained from recent VLBA studies at 43 GHz, and the fact
that very similar kinematics are seen at a different frequency and time with a
different instrument suggests these properties are fundamental characteristics
of this jet. This pilot program demonstrates that KaVA is a powerful VLBI array
for studying the detailed structural evolution of the M87 jet and also other
relativistic jets.Comment: 10 pages, 9 figures, accepted for publication in PAS
The First Very Long Baseline Interferometry Image of 44 GHz Methanol Maser with the KVN and VERA Array (KaVA)
We have carried out the first very long baseline interferometry (VLBI)
imaging of 44 GHz class I methanol maser (7_{0}-6_{1}A^{+}) associated with a
millimeter core MM2 in a massive star-forming region IRAS 18151-1208 with KaVA
(KVN and VERA Array), which is a newly combined array of KVN (Korean VLBI
Network) and VERA (VLBI Exploration of Radio Astrometry). We have succeeded in
imaging compact maser features with a synthesized beam size of 2.7
milliarcseconds x 1.5 milliarcseconds (mas). These features are detected at a
limited number of baselines within the length of shorter than approximately 650
km corresponding to 100 Mlambda in the uv-coverage. The central velocity and
the velocity width of the 44 GHz methanol maser are consistent with those of
the quiescent gas rather than the outflow traced by the SiO thermal line. The
minimum component size among the maser features is ~ 5 mas x 2 mas, which
corresponds to the linear size of ~ 15 AU x 6 AU assuming a distance of 3 kpc.
The brightness temperatures of these features range from ~ 3.5 x 10^{8} to 1.0
x 10^{10} K, which are higher than estimated lower limit from a previous Very
Large Array observation with the highest spatial resolution of ~ 50 mas. The 44
GHz class I methanol maser in IRAS 18151-1208 is found to be associated with
the MM2 core, which is thought to be less evolved than another millimeter core
MM1 associated with the 6.7 GHz class II methanol maser.Comment: 19 pages, 3 figure
Peripheral Arteriovenous Malformations with a Dominant Outflow Vein: Results of Ethanol Embolization
Precessing jet nozzle connecting to a spinning black hole in M87
The nearby radio galaxy M87 offers a unique opportunity to explore the
connections between the central supermassive black hole and relativistic jets.
Previous studies of the inner region of M87 revealed a wide opening angle for
the jet originating near the black hole. The Event Horizon Telescope resolved
the central radio source and found an asymmetric ring structure consistent with
expectations from General Relativity. With a baseline of 17 years of
observations, there was a shift in the jet's transverse position, possibly
arising from an eight to ten-year quasi-periodicity. However, the origin of
this sideways shift remains unclear. Here we report an analysis of radio
observations over 22 years that suggests a period of about 11 years in the
position angle variation of the jet. We infer that we are seeing a spinning
black hole that induces the Lense-Thirring precession of a misaligned accretion
disk. Similar jet precession may commonly occur in other active galactic nuclei
but has been challenging to detect owing to the small magnitude and long period
of the variation.Comment: 41 pages, 7 figures, 7 table