Tsunami: ocean dynamo generator.

Secondary magnetic fields are induced by the flow of electrically conducting seawater through the Earth's primary magnetic field ('ocean dynamo effect'), and hence it has long been speculated that tsunami flows should produce measurable magnetic field perturbations, although the signal-to-noise ratio would be small because of the influence of the solar magnetic fields. Here, we report on the detection of deep-seafloor electromagnetic perturbations of 10-micron-order induced by a tsunami, which propagated through a seafloor electromagnetometer array network. The observed data extracted tsunami characteristics, including the direction and velocity of propagation as well as sea-level change, first to verify the induction theory. Presently, offshore observation systems for the early forecasting of tsunami are based on the sea-level measurement by seafloor pressure gauges. In terms of tsunami forecasting accuracy, the integration of vectored electromagnetic measurements into existing scalar observation systems would represent a substantial improvement in the performance of tsunami early-warning systems.

Three-dimensional echocardiographic pictures of isolated double-orifice mitral valve.

We present a case of a 12-year-old boy with a rare form of cardiac anomaly, isolated double-orifice mitral valve. He was referred to our hospital at 1.5 years old because of heart murmur. Two-dimensional echocardiography showed double-orifice mitral valve without any associated cardiac anomalies. He has been followed carefully without any medication for 11 years. He has had no symptoms and an excellent natural course thus far.

The orphan GPCR GPR87 was deorphanized and shown to be a lysophosphatidic acid receptor.

In CHO cells stably expressing the GPR87 fused with a G16alpha protein, lysophosphatidic acid (LPA) evoked an intracellular Ca(2+) increase in a high affinity manner. The Ca(2+) increase was reversibly blocked by the LPA receptor antagonists and inhibited by pretreatment of the cells with GPR87-specific siRNAs. GPR87 was shown to be closer to the P2Y and P2Y-related receptors than LPA receptors by ClustalW analyses. However, none of nucleotides and their derivatives activated GPR87. The human gpr87 is located on the chromosome 3q25 in a cluster containing p2y12,13,14. RT-PCR analysis showed that the mouse GPR87 was expressed in placenta, ovary, testis, prostate, brain, and skeletal muscle. The 3D model of GPR87-LPA complex indicated that the ligand interacted with R115 and K296 of GPR87, which are well conserved in the P2Y receptors. These results suggest that the GPR87 is a LPA receptor which evolved from a common ancestor of P2Y receptors.

Analysis of Kawasaki disease showing elevated antibody titres of Yersinia pseudotuberculosis.

AIM: To elucidate a clinical difference between patients with Kawasaki disease documented with Yersinia pseudotuberculosis infection and patients with Kawasaki disease without Yersinia pseudotuberculosis infection. PATIENTS AND METHODS: From January 1985 to July 2004, 452 patients were diagnosed with Kawasaki disease. Forty-two patients had elevated antibody titres of Yersinia pseudotuberculosis and/or positive stool culture (Yersinia-positive group). Three hundred and thirty patients had no elevated antibody titres (Yersinia-negative group). We compared the clinical characteristics retrospectively. RESULTS: The age of onset in the Yersinia-positive group (3.05+/-2.20 y) was significantly higher than that in the Yersinia-negative group (2.31+/-2.05 y) (p=0.03). The age-adjusted statistical analysis demonstrated that the incidence of coronary artery lesions (dilatations plus aneurysms) in the Yersinia-positive group (22/42, 52.4%) was significantly higher than in the Yersinia-negative group (105/330, 31.8%) (p=0.001), and the incidence of additional administration of immunoglobulin in the Yersinia-positive group (13/36, 36.1%) was significantly higher than in the Yersinia-negative group (41/256, 16.0%) (p=0.004). CONCLUSION: Our data suggest that Yersinia pseudotuberculosis infection might play a role in the developing mechanism of poor response to therapy and the tendency to develop coronary artery lesions in Kawasaki disease patients.

Successful release of recurrent pulmonary venous obstruction after repair of totally anomalous pulmonary venous connection by transcatheter implantation of stents.

We report a 3-month-old female infant, in whom pulmonary venous obstruction occurred after repair of totally anomalous pulmonary venous connection, and which was successfully released by a transcatheter implantation of a stent using the transseptal approach. Close follow-up is required, since the long-term outcome is still unclear. Nevertheless, transcatheter implantation of stents is a promising option for treating this challenging lesion.

Transcatheter polytetrafluoroethylene-covered stent implantation in a giant coronary artery aneurysm of a child with Kawasaki disease--a potential novel treatment.

We report a case of an eight-year-old boy with Kawasaki disease (KD) who had a giant aneurysm with stenotic lesions located in the right coronary artery, and was treated by transcatheter implantation of a polytetrafluoroethylene(PTFE)-covered stent. Follow-up coronary angiography showed good coronary blood flow. To the best of our knowledge, this is the first child with KD who underwent covered-stent implantation in a coronary aneurysm. Although close follow-up is mandatory, because the long-term outcome is unclear, implantation of a covered stent in a giant aneurysm appears to be a promising treatment option.

Geophysical evidence from the MELT area for compositional controls on oceanic plates.

Magnetotelluric and seismic data, collected during the MELT experiment at the southern East Pacific Rise, constrain the distribution of melt beneath this mid-ocean-ridge spreading centre and also the evolution of the oceanic lithosphere during its early cooling history. Here we focus on structures imaged at distances approximately 100 to 350 km east of the ridge crest, corresponding to seafloor ages of approximately 1.3 to 4.5 million years (Myr), where the seismic and electrical conductivity structure is nearly constant and independent of age. Beginning at a depth of about 60 km, we image a large increase in electrical conductivity and a change from isotropic to transversely anisotropic electrical structure, with higher conductivity in the direction of fast propagation for seismic waves. Conductive cooling models predict structure that increases in depth with age, extending to about 30 km at 4.5 Myr ago. We infer, however, that the structure of young oceanic plates is instead controlled by a decrease in water content above a depth of 60 km induced by the melting process beneath the spreading centre.

A variant of congenital muscular dystrophy.

We analyzed three Japanese patients (two boys and a girl) from two families with congenital muscular dystrophy (CMD) and brain involvement. One of the two families had two affected siblings of different sexes. Parental consanguinity was not documented in either family. All patients showed generalized hypotonia and weakness from infancy, delayed psychomotor development, facial muscle involvement, and joint contractures. Serum creatine kinase levels were markedly elevated. The histological change seen on muscle biopsy was characteristic of a dystrophic process, although dystrophin and merosin staining were normal. On MR imaging, cortical dysplasia and cerebral white matter abnormalities were observed. Although these clinical, myopathological and neuroradiological findings were typical of Fukuyama-type CMD (FCMD), full mutational analysis of the fukutin gene revealed neither a 3 kb insertion (Japanese founder mutation) nor point mutations. RT-PCR analysis of RNA isolated from lymphoblasts of a patient revealed normal expression of the FCMD transcript. As classification of CMD should be based on genetic background, our present cases with typical clinical, myopathological and neuroradiological findings of FCMD without mutation of the fukutin gene may represent a new variant (or variants) of CMD that is different from FCMD.