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A Sekizawa

Publications and source records attributed to A Sekizawa.

At least 19 recordsLinked to original sources
PubMed2006

Velamentous cord insertion into the lower third of the uterus is associated with intrapartum fetal heart rate abnormalities.

OBJECTIVES: To evaluate the accuracy of sonographic identification of the site of umbilical cord insertion (CI) at 18-20 weeks of gestation, to compare the sensitivities for detection of a velamentous cord insertion (VCI) secondary to a CI into the anterior, posterior or fundal wall, and to compare the intrapartum complications secondary to VCI into the upper, middle or lower third of the uterus. METHODS: As part of the routine ultrasound scan at 18-20 weeks' gestation we evaluated abnormal CI (VCI and marginal CI) and the location of the CI in the uterus in 3446 pregnancies. In cases of abnormal CI, the location of the CI was further classified as being in the upper, middle or lower third of the uterus. After delivery, the placenta and the umbilical cord were examined and intrapartum complications were compared with the location of the CI. RESULTS: The values for antenatal detection of VCI were: sensitivity, 25 of 40 (62.5%); positive predictive value, 25 of 25 (100%); and negative predictive value, 3406 of 3421 (99.6%). The sensitivity for cases in which the CI was located on the anterior wall was 12 of 13 (92.3%); when it was located on the posterior wall, the sensitivity was 11 of 22 (50.0%); and when it was fundal the sensitivity was 2 of 5 (40.0%). Variable decelerations were frequently observed with a VCI. In lower VCI cases, non-reassuring fetal heart rate patterns and emergency Cesarean sections occurred with a higher frequency than in cases with upper or middle VCI (P < 0.01). After delivery, the length of the aberrant vessels in cases of VCI by pathologic examination was 3.9 +/- 3.3 cm in the upper third, 4.7 +/- 4.6 cm in the middle third, and 10.6 +/- 6.8 cm in the lower third; thus, the aberrant vessel length was significantly greater when the CI was in the lower third of the uterus (P = 0.024). CONCLUSION: We have demonstrated that VCI with a lower CI site and with longer aberrant vessels is associated with various intrapartum complications. This finding has the potential for improving perinatal outcome.

Female↗
PubMed2006

Cord insertion into the lower third of the uterus in the first trimester is associated with placental and umbilical cord abnormalities.

OBJECTIVES: To assess the feasibility of detecting the cord insertion site during the late first trimester, and to investigate the possible association between perinatal complications and a cord insertion in the lower third of the uterus in the first trimester. METHODS: This was a prospective cohort study in which the positional relationship between the uterus and the cord insertion site was examined using gray-scale transvaginal sonography at 9-11 weeks of gestation. The distance between the internal os and the fundus was divided equally into three parts. Cord insertions located in the upper or middle thirds were defined as normal (controls), and those located in the lower third were defined as cases, regardless of their relationship to the chorion villosum. Third-trimester sonography and pathological examination of the placenta and cord at delivery were performed to check for placental/cord abnormalities. The univariate association between the location of the cord insertion in the first trimester and placental and umbilical cord abnormalities and perinatal complications was assessed. RESULTS: The cord insertion site was identified in 318/340 (93.5%) cases at 9-11 weeks of gestation and it was in the lower third of the uterus in 35 (11.0%) cases. Of these 35, the cord insertion was found at delivery to be low in nine cases (26%) and the placenta was low-lying at delivery in eight (23%). None of the 283 cases with a normal cord insertion in the first trimester was found to have a low-lying placenta at delivery (P < 0.0001). Ten (29%) of the cases with a low cord insertion and four (1.4%) with a normal cord insertion in the first trimester had a velamentous or marginal cord insertion at delivery (P < 0.0001). At delivery, five (14%) of the low cord insertion cases and four (1.4%) of the normal cord insertion cases (P < 0.0001) had some form of placental malformation, including accessory placenta and infarction of the placenta. An emergency Cesarean section was performed in four (11%) and six (2.1%) of the low and normal cord insertion cases, respectively (P = 0.003). CONCLUSION: Developmental abnormalities of the placenta and umbilical cord occur frequently in cases in which the cord insertion is in the lower third of the uterus in the first trimester. We suggest that screening for the cord insertion site at 9-11 weeks of gestation may have clinical significance for predicting abnormalities of the cord and the placenta at delivery.

Adult↗
PubMed2006

Measurement of mRNA of trophoblast-specific genes in cellular and plasma components of maternal blood.

BACKGROUND: Placental mRNA in maternal plasma is suitable for quantitative analysis regardless of fetal gender and genetic polymorphism status. METHODS: We obtained 155 blood samples from pregnant women to compare human placental lactogen (hPL) and beta-subunit of human chorionic gonadotropin (beta hCG) mRNA and protein levels between the cellular and plasma components of maternal blood. To assess clearance of hPL mRNA expression, we obtained blood samples from nine women immediately before and after delivery by caesarean section. mRNA was extracted from the cellular and plasma components of all samples, and hPL and beta hCG mRNA expression was analysed by reverse transcription-PCR assay. RESULTS: The concentration of beta hCG mRNA in the cellular component positively correlated with the plasma concentration of beta hCG protein and beta hCG mRNA (p = 0.001 for both). The concentration of hPL protein in the plasma correlated with the hPL mRNA concentration of the cellular component (p<0.05). For both hPL and beta hCG, the mRNA concentration of the cellular component was greater than that of the plasma component (22.9-fold higher for hPL and 4.3-fold higher for beta hCG). The half life of hPL mRNA clearance was significantly longer for the cellular fraction (mean half life = 203.8 min, range 150-3465 min) than for the plasma fraction (mean half life = 32.2 min, range 15-385 min) (p = 0.008). CONCLUSION: The present findings indicate that the concentration of hPL and beta hCG mRNA is significantly higher in the cellular component of maternal blood samples than in the plasma component. Cellular mRNA in maternal blood is useful for non-invasive evaluation of placental function.

Chorionic Gonadotropin↗
PubMed2005

Velamentous cord insertion and atypical variable decelerations with no accelerations.

OBJECTIVES: To examine intrapartum fetal heart rate (FHR) patterns in the presence of velamentous cord insertion (VCI). METHODS: The site of cord insertion was determined in 1460 women on antenatal ultrasonographic and postnatal examinations. Each of 24 women with pregnancies complicated with VCI was matched at the onset of labor with 10 women who had a normal pregnancy, and FHR patterns were analyzed for both cases and controls. RESULTS: Compared with controls, cases of variable decelerations with no accelerations (VDNA) during the first and second stages of labor were more frequent in women with VCI (first stage: 25% vs. 5.1%, second stage: 65.0% vs. 21.7%, P < 0.001). The adjusted odds ratio associated with VDNA occurrence in women with VCI was 3.83 (95% confidence interval [CI]: 1.51-9.72, P = 0.005). The mean odds ratio associated with length of aberrant vessels in women with VCI plus VDNA was 1.38 (95% CI: 1.04-1.83, P = 0.026). CONCLUSION: Pregnancies complicated with VCI are associated with a higher rate of VDNA.

Adult↗
PubMed2004

Malignant transformation of endometriosis and genetic alterations of K-ras and microsatellite instability.

OBJECTIVES: To clarify the role of specific genetic alterations in the multi-step process of malignant transformation of endometriosis. METHODS: In cases of ovarian endometrioid carcinoma, we separated regions of normal endometriosis, atypical endometriosis and ovarian endometrioid carcinoma by laser microdissection, and examined K-ras mutation and microsatellite instability in each separated tissue sample. RESULTS: We detected K-ras mutation and microsatellite instability in endometrioid carcinoma tissue, but not in normal or atypical endometriosis bordering the cancerous region. CONCLUSIONS: The present findings suggest that K-ras mutation and microsatellite instability are associated with malignant transformation from atypical endometriosis to ovarian endometrioid carcinoma.

Adult↗
PubMed2001

Steroid sulfatase expression in ovarian clear cell adenocarcinoma: immunohistochemical study.

OBJECTIVE: Steroid sulfatase (STS) is an important enzyme that converts biological inactive steroid sulfate to active free steroid. As estrogen is thought to play an important role in cell proliferation in gynecological cancer, the existence of STS may have particular significance in the prognosis of ovarian cancer. In the present study, we determined the STS expression of ovarian clear cell adenocarcinoma (OCCA), which has the poorest prognosis among various ovarian cancers, immunohistochemically to clarify the biological nature of OCCA and also to determine whether STS expression is one of the prognostic factors in OCCA. METHODS: Forty-five archival, formalin-fixed, paraffin-embedded tissues from patients with OCCA and other epithelial ovarian cancers who were first operated on from 1987 to 1998 were subjected to analysis. Twenty-eight of forty-five (60.9%) OCCA cases coexisted with endometriosis. They were subclassified into papillary, solid, and tubulocystic types with respect to architectural pattern. Immunohistochemical staining of STS was performed using anti-human STS polyclonal rabbit antibody that had been immunized with purified STS from human placenta. RESULTS: STS was immunohistochemically stained positively in 70% (32/45) of OCCA, 33.3% of serous adenocarcinoma (6/18), and 50.0% of mucinous adenocarcinoma (4/8) specimens and was localized in the cytoplasm of neoplastic epithelial cells. No significant relationship was found between STS staining and FIGO staging. However, patients diagnosed as papillary type had a significantly lower survival rate and showed significantly more positive staining of STS (P < 0.05) than those with solid type. Stage, STS expression, and architectural type yielded a significant association with survival rate. CONCLUSION: It was proven that STS is present in the cytoplasm of patients with OCCA by an immunohistochemical method. OCCA patients with papillary tumor with positive STS expression are considered to have a poor prognosis.

Adenocarcinoma, Clear Cell↗
PubMed2001

Prenatal screening of single-gene disorders from maternal blood.

Fetal cells and cell-free fetal DNA can be found circulating in maternal blood. Fetal cells recovered from maternal blood provide the only source of pure fetal DNA for noninvasive prenatal DNA diagnosis. Fetal nucleated erythrocytes (NRBCs) are considered the most suitable maternally-circulating fetal cells for this purpose, because they are not commonly found in the peripheral blood of healthy adults and are most abundant in the fetus during early gestation. Because fetal cells in maternal blood are extremely rare, a definitive separation method has not yet been established. Fetal NRBCs can be enriched from maternal blood via fluorescence- or magnetic-activated cell sorting, density gradients, immuno-magnetic beads or micromanipulation. Fetal cells are identified by Giemsa staining, hybridization with Y-chromosome specific probes, PCR-detection of a specific paternal allele, or immunostaining for fetal cell antigens. Amplification of fetal DNA sequences by primer extension preamplification and PCR has allowed prenatal screening for Duchenne muscular dystrophy and the fetal RhD blood type. Sequence-specific hybridization has been used to detect sickle cell anemia and beta-thalassemia prenatally in heterozygous carriers of these disorders. The use of cell-free fetal DNA in maternal plasma for the diagnosis of single-gene disorders is limited to disorders caused by a paternally inherited gene or a mutation that can be distinguished from the maternally inherited counterpart. At present, fetal gender can be determined from maternal plasma. When a pregnant woman is a heterzygous carrier of an X-linked disorder, the determination of fetal gender is clinically very informative for first-step screening to avoid invasive amniocentesis. The non-invasive prenatal diagnosis of genetic disorders should be applied to pregnant women with a definite risk for a specific single-gene disorder.

Cell Separation↗
PubMed2000

Prenatal DNA diagnosis of a single-gene disorder from maternal plasma.

Achondroplasia is a short-limb disorder caused by a point mutation in a single gene. To diagnose such a disorder prenatally requires the use of invasive procedures such as amniocentesis. However, using PCR and restriction fragment length polymorphism analysis, we were able to detect the mutation in the plasma of a woman carrying a fetus suspected of having achondroplasia. The detection of a fetus-derived mutant gene from maternal plasma may therefore permit non-invasive prenatal diagnosis of single-gene disorders.

Achondroplasia↗
PubMed2000

Comparison of fetal cell recovery from maternal blood using a high density gradient for the initial separation step: 1.090 versus 1.119 g/ml.

The purpose of this study was to improve recovery of fetal nucleated erythrocytes (NRBCs) from maternal blood for non-invasive prenatal diagnosis. Peripheral blood samples were obtained from 27 women who had just undergone pregnancy termination at 6 to 23 weeks. Samples were split and mononuclear cells were isolated using Histopaque gradient at densities of 1.090 g/ml and 1.119 g/ml. CD45 depletion using magnetic activated cell-sorting, followed by flow-sorting with antibody to gamma-globin and fluorescence in situ hybridization (FISH) analysis, were used to evaluate the number of fetal NRBCs recovered. In samples separated with the 1.119 g/ml density gradient, the yield of true anti-gamma haemoglobin positive cells (median, 14. 9; range, 0-717.5) was significantly higher than that with the 1.090 g/ml density gradient (median, 4.9; range, 0-532.5). After FISH analysis, in the 14 samples in which the fetal karyotype differed from the mother, the median number of fetal NRBCs separated by the 1. 119 g/ml density gradient was 22.9 (2-717.5), which was significantly higher than that by the 1.090 g/ml gradient (median, 11.5; range, 0-532.5, p=0.022). Increased density of the gradient used for the initial enrichment of fetal cells results in improved fetal cell recovery in fresh post-termination blood samples, which may permit better non-invasive detection of fetal cells in maternal blood.

Blood Cells↗
PubMed2000

Apoptosis in fetal nucleated erythrocytes circulating in maternal blood.

The purpose of this study was to determine if apoptosis occurs in fetal cells that have crossed into the maternal circulation, which would potentially explain the difference between the number of intact fetal cells and the amount of fetal DNA detectable in maternal plasma. We flow-sorted fetal nucleated erythrocytes (FNRBCs) using antibody to the gamma chain of fetal haemoglobin and confirmed them to be fetal in origin by FISH analysis using chromosome-specific probes. Fetal cells were then analysed microscopically for the presence of terminal UdTP nuclear end labelling (TUNEL) staining. Apoptotic change was observed in 42.7% of fetal NRBCs (106/246) and 3.5% of maternal cells (29/818). Results of this study indicate that a significant number of fetal cells in maternal blood are undergoing apoptosis at the time of sampling. Apoptosis may be one mechanism by which fetal cells are cleared by the maternal circulation.

Adult↗
PubMed2000

Female fetal cells in maternal blood: use of DNA polymorphisms to prove origin.

The nucleated erythrocyte (NRBC) is one of the target fetal cell types for noninvasive genetic diagnosis using maternal peripheral blood. However, it is now known that pregnancy can stimulate the production of maternal NRBCs. When isolating female gamma-positive NRBCs, fluorescence in situ hybridization (FISH) analysis may show two X chromosome signals per nucleus, and therefore it cannot be conclusively determined whether the isolated cells are fetal or maternal in origin. The purpose of this study was to develop a means of verifying that a female cell is fetal on the basis of polymorphic short tandem repeat markers. Peripheral blood samples were obtained from women who had just undergone termination of pregnancy. Nucleated candidate fetal cells were isolated by flow-sorting using antibody to the gamma-chain of fetal hemoglobin and Hoechst 33342. FISH analysis was performed using X and Y chromosome specific probes. Female gamma-positive cells and leukocytes were micromanipulated separately and subjected to fluorescent polymerase chain reaction amplification of chromosome 21 and/or 18 STR markers (D21S11, D21S1411, D21S1412, and D18S535). In all ten cases analyzed, the gamma-positive female candidate fetal cells were determined to be fetal in origin by the presence of shared and nonshared DNA polymorphisms when compared with maternal leukocytes. These results show that genetic analysis can be performed on all fetal NRBCs, including female fetal cells that cannot be distinguished from maternal cells based on FISH analysis alone.

Cell Separation↗
PubMed2000

Detection of male and female fetal DNA in maternal plasma by multiplex fluorescent polymerase chain reaction amplification of short tandem repeats.

The purpose of this study was to develop a fluorescent polymerase chain reaction (PCR) assay for the detection of circulating fetal DNA in maternal plasma. Maternal DNA extracted from plasma samples of pregnant women at term and newborn DNA isolated from cord blood were used to genotype 12 mother/child pairs at nine different polymorphic short tandem repeat loci. Multiplex fluorescent PCR was used to detect fetus-specific alleles in the corresponding maternal plasma samples. Fetus-specific alleles were found in all maternal plasma samples studied. Using these polymorphic repeat sequences, every mother/child pair was informative in at least four of nine loci. Paternally inherited fetal alleles were detected in 84% of informative short tandem repeats. This approach may have implications for non-invasive prenatal diagnosis. Compared with other fetal DNA detection systems that use fetus-derived Y sequences to detect only male fetal DNA in maternal plasma, our proposed technique can be applied to both female and male fetuses.

Alleles↗
PubMed1999

Fetal cell recycling: diagnosis of gender and RhD genotype in the same fetal cell retrieved from maternal blood.

OBJECTIVE: Our aim was to develop a new technique, which we have termed fetal cell recycling, that combines the 2 powerful methods of fluorescence in situ hybridization and polymerase chain reaction to maximize the genetic information available from a small number of fetal nucleated erythrocytes obtained noninvasively from the blood of pregnant women. STUDY DESIGN: Blood samples were obtained from 4 Rh-negative women after elective termination of pregnancy at 7 to 17 weeks' gestation. Fetal nucleated erythrocytes were separated by flow sorting with antibody to the gamma chain of fetal hemoglobin. Fluorescence in situ hybridization with chromosome-specific probes was used to diagnose fetal gender. After fluorescence in situ hybridization analysis the fetal nucleated erythrocytes were recycled by a micromanipulation technique and deoxyribonucleic acid diagnosis was performed with polymerase chain reaction amplification of the RhD gene. RESULTS: Among the 4 case patients we detected a total of 101 fetal nucleated erythrocytes. All targeted cells were successfully retrieved with a micromanipulator. In each case we successfully performed both fluorescence in situ hybridization and polymerase chain reaction analysis. The predicted fetal gender and Rh status corresponded to the results obtained from fetal tissue. CONCLUSIONS: Fetal cell recycling combines the powers of highly sensitive molecular methods to maximize the genetic information available from a single fetal cell. This technique will permit noninvasive diagnosis of recessively inherited single-gene disorders.

Aneuploidy↗
PubMed1999

Latent class analysis applied to patterns of fetal sonographic abnormalities: definition of phenotypes associated with aneuploidy.

The aim of the present study was to generate different latent variables that classify the major chromosome aneuploidies using frequency and patterns of fetal sonographic abnormalities in a large database. A total of 1867 fetuses with sonographic abnormalities recorded in a database at New England Medical Center from January 1995 to March 1998 were available for the statistical analysis. Included within this group were 61 aneuploid fetuses, including 11 with 45,X, 30 with trisomy 21, 14 with trisomy 18 and 6 with trisomy 13, 40 structural malformations and/or sonographic markers were detected in these 61 aneuploid fetuses. The ability of malformations and sonographic markers to generate different groups of phenotypes was evaluated by means of latent class analysis, using the 61 affected cases. Four different classes were generated with the hypothetical assumption that each of them could satisfactorily identify a respective fetal aneuploidy represented in the study group. Among 40 fetal malformations and/or sonographic markers, the most important findings in generating specific karyotypic groups were cystic hygroma (class 1), duodenal atresia (class 2), holoprosencephaly (class 3) and omphalocele (class 4), respectively. Accuracy of the classification was 72 per cent for Turner syndrome (class 1), 74 per cent for Down syndrome (classes 1 and 2), 88 per cent for trisomy 13 (class 3) and 93 per cent for trisomy 18. The frequency of associated malformations detected sonographically can help to define a phenotype that is likely to be representative of a specific aneuploidy. Before the definitive karyotype is available or, in cases in which patients refuse an invasive prenatal diagnostic procedure, this may improve antenatal clinical management.

Aneuploidy↗