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Osamu Miyoshi

Publications and source records attributed to Osamu Miyoshi.

3 recordsLinked to original sources

Immunocytochemical study of activin type IB receptor (XALK4) in Xenopus oocytes.

Studies have shown that the activin type IB receptor is specific for activin/nodal signaling. Activin is produced by follicle cells in the ovary, and is incorporated into the oocytes. Antisera against three peptides were prepared, encompassing the extracellular, intracellular and serine/threonine kinase domains of the Xenopus type IB activin receptor (XALK4). Immunocytochemistry was done using these antisera to investigate the distribution of XALK4 in the Xenopus ovary. All three antisera stained the mitochondrial cloud of Xenopus previtellogenic oocytes. Purified antibody against the intracellular domain also recognized the mitochondrial cloud. Immunoelectron microscopy localized XALK4 on the endoplasmic reticulum of the mitochondrial cloud, although not on mitochondria.

Activin Receptors↗

A tetraploid liveborn neonate: cytogenetic and autopsy findings.

Cytogenetic and autopsy findings of a nonmosaic tetraploid male neonate, alive until shortly after birth at 37 weeks' gestation, are described. Oligohydramnios, intrauterine growth retardation, cranial abnormalities, and Dandy-Walker malformation were noted prenatally. Autopsy findings included cleft lip and palate; overlapping fingers; low-set ears; simian creases; hypoplastic external genitalia with undescended testes; Dandy-Walker malformation; slightly dilated lateral and third ventricles; hypoplasia of the cerebrum, pons, medulla, pituitary gland, thymus, lung, adrenal gland, and kidney; large ventricular septal defect; and enteric cyst behind the urinary bladder. The placenta was hypoplastic and showed no remarkable abnormalities, except for mild syncytial knots. Chromosome analyses of amniotic fluid cells at 31 weeks' gestation and the umbilical cord blood cells at delivery revealed a 92,XXYY karyotype. G-, C-, Q-, and N-banding heteromorphic studies demonstrated duplication of paternal chromosomes 1, 3, and 15, and maternal chromosome 22. In addition, the results of an analysis with 16 CA repeat polymorphic markers were consistent with duplicated inheritance of 1 paternal and 1 maternal haploid sets to the tetraploid patient. Therefore, it is most likely that the tetraploidy was caused by a cytoplasmic cleavage failure at the first mitotic division.

Brain↗