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Michiko Yamanaka

Publications and source records attributed to Michiko Yamanaka.

9 recordsLinked to original sources
PubMed2006

Origin and mechanisms of formation of fetus-in-fetu: two cases with genotype and methylation analyses.

Fetus-in-fetu (FIF) is a condition in which a host infant has a fetus-like mass(es) within its body. We describe here results of molecular genetic analysis in two cases of FIF. In FIF-1, a male host had two retroperitoneal fetiform masses each with a vertebral column, and in FIF-2, a fetiform mass with vertebral column was present in the cranial cavity of a male host. Genotyping of each case using microsatellite markers showed that the host infant and its fetus(es) inherited one copy each of parental alleles and shared identical genotypes. These findings were confirmed by single nucleotide polymorphism (SNP) analysis using Affymetrix GeneChip Human Mapping 50K Array, and supported a monozygotic twin theory of FIF. Analysis of the methylation status was done in both cases at the differentially methylated region (DMR) within the human IGF2-H19 locus after bisulfite treatment, methylation-specific PCR, and cloning of PCR products. Normally, only the paternal allele is methylated and the maternal allele unmethylated in DMR. However, in FIF-1, 7 (46.7%) of 15 clones from a fetiform mass and 6 (66.7%) of 9 clones from the other mass showed an unmethylated paternal allele, while the methylation status of a host infant and its fetiform mass in FIF-2 was the same in all clones examined with normal patterns. These data suggest that in FIF-1, two isolated blastocysts originated from one zygote, one of the two was implanted into (or included by) the other blastocyst during the process of methylation, and such abnormal implantation may have occurred in FIF-2 after the establishment of methylation. This is the first case of FIF showing different methylation patterns between a host infant and fetiform mass.

Adult↗
PubMed2006

Pregnancy outcome of fetuses with trisomy 18 identified by prenatal sonography and chromosomal analysis in a perinatal center.

To investigate the pregnancy outcome of fetuses affected with trisomy 18, we analyzed 63 cases diagnosed at our hospital from January 1993 to December 2004. Twenty-nine were males and 34 were females. Fifty-eight were prenatally diagnosed, and in 16 (27.6%) of them intrauterine fetal death (IUFD) occurred between 28 weeks and 41 weeks gestation (34.6 +/- 3.9 weeks, Mean +/- SD). Ten (17.2%) fetuses died during labor and their age ranged from 30 weeks to 40 weeks of gestation. The total number of cases ending in fetal demise was 26 (44.8%) and the mean gestational age at the time of fetal demise was 35.0 +/- 3.6 weeks (Mean +/- SD). All liveborn infants (n = 36) were born after 31 weeks gestation. In our study the preterm birth ratio for trisomy 18 is 34.8%, which is much higher than the ratio for the general population. Females are more likely than males to be long-term survivors. These data are helpful in the counseling of parents faced with the difficult decision of whether or not to continue a pregnancy with a fetus affected with trisomy 18.

Chromosomes, Human, Pair 18↗
PubMed2006

A large interstitial deletion of 17p13.1p11.2 involving the Smith-Magenis chromosome region in a girl with multiple congenital anomalies.

A 6-month-old girl had multiple congenital anomalies, including dysmorphic face; tetralogy of Fallot, pulmonary atresia and patent ductus arteriosus; congenital cystic adenomatoid malformation of the right upper lung, and hemilateral kidney defect. Chromosome analysis as well as fluorescence in situ hybridization (FISH) and polymorphic marker analyses in the girl and her parents revealed a de novo large interstitial deletion of 17p13.1-p11.2 of the paternally derived chromosome 17. The deletion involved the Smith-Magenis chromosome region (SMCR). Lack of involvement of the Miller-Dieker syndrome region at 17p13.3 was confirmed by both FISH analysis and radiological examinations that showed no migrational abnormality. The girl died at age 7 months. This is the first report of a patient with a large interstitial deletion of 17p.

Abnormalities, Multiple↗
PubMed2004

Pericardial hemangioma presenting fetal cardiac tamponade and postnatal bronchostenosis.

A case of pericardial hemangioma is described which was resected in the neonatal period due to its effect on the cardiopulmonary system. Preoperative differential diagnosis of a teratoma was difficult. Surgical extirpation resulted in massive bleeding and postoperative bronchomalacia. These complications suggest that we should choose a conservative therapy as often as possible.

Bronchi↗
PubMed2004

Maternal, neonatal, and placental features associated with diffuse chorioamniotic hemosiderosis, with special reference to neonatal morbidity and mortality.

OBJECTIVE: Our purpose was to examine the significance of diffuse chorioamniotic hemosiderosis (DCH) on neonatal morbidity and mortality. METHODS: Using data from a retrospective case-control study, we analyzed 46 singleton placentas with DCH from infants who were delivered and/or admitted to the neonatal intensive care unit of Kanagawa Children's Medical Center during 1987-2001 and 92 control placentas without DCH from infants of comparable gestational age, birth weight, and duration. RESULTS: Mean and standard deviation of gestational age and infants' birth weight at delivery from the DCH group were 27 +/- 3 weeks and 939 +/- 342 g, respectively. Macroscopically, the placentas with DCH were more likely to show old peripheral blood clots (46% in the DCH group vs 8% in control group), subchorionic hematoma (20% vs 1%), and circumvallation (13% vs 1%). Histologically, amniotic necrosis was significantly more frequent in the DCH group (63% vs 24%). Of the obstetric factors, incidence of recurrent episodes of vaginal bleeding (70% vs 11%), oligohydramnios (59% vs 8%), and chronic abruption-oligohydramnios sequence (57% vs 5%) were significantly higher in the DCH group. Of the neonatal factors, persistent pulmonary hypertension of the newborn (29% vs 8%) and dry lung and/or pulmonary hypoplasia (20% vs 4%) were more common. However, respiratory distress syndrome was rare (15% vs 45%) in the DCH group. Neonatal death including stillbirth was increased in the DCH group but was not significant (24% vs 15%). Of infants who survived beyond day 28, chronic lung disease (CLD) was more frequent in the DCH group (51% vs 22%). The association of DCH, especially accompanied by amniotic necrosis, with CLD was still evident using likelihood ratio test. CONCLUSION: DCH is closely associated with preterm delivery, pulmonary hypertension of the newborn, and dry lung syndrome and is a significant risk factor for CLD.

Abruptio Placentae↗
PubMed2002

Paternal UPD14 is responsible for a distinctive malformation complex.

We present a boy and two girls with paternal uniparental disomy of chromosome 14q (patUPD14). One girl had a Robertsonian translocation, whereas two a normal karyotype. Based on the manifestations of these patients and four previously reported patients who all had translocated chromosome 14, The patUPD14 was thought to constitute a distinctive syndrome. The hallmarks included abdominal muscular defects, skeletal anomalies, and characteristic facies. The phenotype of patUPD14 was consistent with that of a previously reported mouse model, i.e., mouse embryos with paternal uniparental disomy of chromosome 12 that has a region orthologous to that of human chromosome 14. Dose effects of newly recognized imprinted genes on human chromosome 14q32, DLK1 and GTL2, could play an important role in the pathogenic mechanism of the distinctive malformation complex.

Abnormalities, Multiple↗
PubMed2002

Re-evaluation of chorioamnionitis and funisitis with a special reference to subacute chorioamnionitis.

Our purpose is to prove that prolonged inflammation of the chorionic plate, which we have termed subacute chorioamnionitis (SCAM), is a distinctive entity and should be differentiated from acute chorioamnionitis (ACAM) because it is an excellent prognostic indicator of chronic lung disease (CLD), including Wilson-Mikity syndrome (WMS). Ninety singleton placentas with stage-3 chorioamnionitis were delivered at 23 to 32 weeks of gestation during 1993 to 1996, and the infants survived more than 28 days. There were 49 placentas with stage 3 SCAM, 33 placentas with stage 3 ACAM, and 8 placentas with subacute necrotizing funisitis (SNF) and without inflammation of the chorionic plate. Fifty-three of gestation- and birthweight-matched placentas without chorioamnionitis were selected as control. To determine the risk factors for CLD, 27 clinical and 6 histological variables were analyzed. Logistic regression analysis showed that amniotic necrosis (AN) (P =.0168) and low birthweight (P =.0341) were the major contributing risk factors for CLD. SNF was not significantly related to CLD. Patients with SCAM (AN+, SNF-) were highly susceptible to CLD. In conclusion, SCAM, especially when associated with AN, seems to be a unique prognostic indicator of CLD.

Amnion↗
PubMed2002

Specific determination of bromate in bread by ion chromatography with ICP-MS.

A sensitive method for detecting bromate in bread by ion chromatography with inductively-coupled plasma mass spectrometry (IC/ICP-MS) was developed. Bromate was extracted from bread with water. The clean-up procedure included a 0.2 micron filter, a C18 cartridge for defatting, a silver cartridge to remove halogen anions, a centrifugal ultrafiltration unit to remove proteins, and a cation-exchange cartridge to remove silver ions. A 500 microL sample solution was applied to IC/ICP-MS. The detection limit and the quantitation limit of bromate in the solution were 0.3 ng/mL and 1.0 ng/mL, expressed as HBrO3, respectively, which corresponded to 2 ng/g and 5 ng/g, respectively, in bread. Recovery of bromate was about 90%, and the CV was about 2%. Based on the detection limit in solution and recovery from bread, the detection limit of bromate in bread was estimated to be 2 ng/g.

Bread↗