Interrelation of the stagnant slab, Ontong Java Plateau, and intraplate volcanism as inferred from seismic tomography.

We investigated the seismological structure beneath the equatorial Melanesian region, where is tectonically unique because an immense oceanic plateau, a volcanic chain and subduction zones meet. We conducted a multi-frequency P-wave tomography using data collected from an approximately 2-year-long seismic experiment around the Ontong Java Plateau (OJP). High-velocity anomalies were revealed beneath the center of the OJP at a depth of ~ 150 km, the middle-eastern edge of the OJP at depths of 200-300 km, and in the mantle transition zone beneath and around the OJP; low-velocity anomalies were observed along the Caroline volcanic island chain above 450 km depth.

Structure of the tsunamigenic plate boundary and low-frequency earthquakes in the southern Ryukyu Trench.

It has been recognized that even weakly coupled subduction zones may cause large interplate earthquakes leading to destructive tsunamis. The Ryukyu Trench is one of the best fields to study this phenomenon, since various slow earthquakes and tsunamis have occurred; yet the fault structure and seismic activity there are poorly constrained. Here we present seismological evidence from marine observation for megathrust faults and low-frequency earthquakes (LFEs).

[MBL quality control survey of autoantibodies--25 years of activity and its achievement--mainly antinuclear antibodies].

Annual MBL Quality Control Survey of Autoantibodies has continued to this day since it started in 1983 as the only quality control survey of autoantibodies in Japan. The survey has aimed at unification and standardization of measurement value, as well as finding out between-laboratory differences in results through reporting the results of tabulation to the participating laboratories. For carrying out the survey, we intend to make our efforts to promote assurance and standardization of the quality control of the autoantibodies.

Augmentation of pulmonary vein backflow velocity during left atrial contraction: a novel phenomenon responsible for progression of atrial fibrillation in hypertensive patients.

Background: Atrial fibrillation (AF) is a common arrhythmia showing disease progression. However, echocardiographic prediction of such progression remains incomplete. This study aimed to identify echocardiographic predictors of AF progression in hypertensive patients.

Early acral melanoma in situ: correlation between the parallel ridge pattern on dermoscopy and microscopic features.

In non-white populations, acral skin is the most prevalent site of malignant melanoma. Early melanomas of this anatomic site are often misdiagnosed as melanocytic nevi, which are not uncommon on acral skin. In fact, clinical and/or histopathological features of melanocytic nevi occasionally mimic those of early acral melanoma and vice versa, and thus differentiation of early acral melanoma from melanocytic nevus is sometimes very difficult for clinicians as well as for histopathologists.

[Autoantibodies].

The autoantibody test gives significant information for diagnosis of autoimmune diseases. Since the finding of the LE-cell in 1948, dozens of autoantibodies have been found. Anti nuclear antibody (ANA) is the essential test for the screening of autoantibodies.

Significance of dermoscopic patterns in detecting malignant melanoma on acral volar skin: results of a multicenter study in Japan.

Objective: To determine diagnostic variables such as sensitivity and specificity of the major dermoscopic patterns observed in melanocytic lesions on acral volar skin, with particular attention to the significance of the parallel ridge pattern and irregular diffuse pigmentation in detecting acral melanoma.

Design: Multicenter, retrospective study.

Setting: University hospitals in Japan.