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Biomedical subjects

T Ishimaru

Publications and source records attributed to T Ishimaru.

At least 73 records · Page 4Linked to original sources
PubMed1996

A partial hydatidiform mole with 2N/3N mosaicism identified by molecular analysis.

PURPOSE: A placenta with a partial hydatidiform mole was studied using DNA polymorphic markers to determine whether it has a triploid cell line. METHOD: Parent-mole transmission of alleles at 23 polymorphic loci was traced in cells from a molar region and a normal-looking region of the placenta by polymerase chain reaction (PCR) amplification or Southern blot analysis, both followed by densitometric analysis. RESULTS: Allele patterns for 8 of the 23 loci were identical between the DNA from the molar and normal regions of the placenta, while those of the remaining 15 loci were uninformative. In the molar region, the band intensity for the paternally derived allele at each informative locus was always greater than that of the maternally derived allele, the average intensity ratio of the former to the latter being 1.5, whereas the ratio in the normal region was even. CONCLUSIONS: The results suggested that the molar region was a mixoploid consisting of diploid and triploid cells and the phenotypically normal region had a mainly diploid constitution. It is most likely that the placenta may have originated from a single diploid or triploid conceptus, followed by postzygotic gain or loss of a paternal haploid set, and that an extra paternal set contributed to hydropic changes of the placenta.

Diploidy↗
PubMed1996

Change in fetal urine production rate in growth-restricted fetuses after maternal meal ingestion.

OBJECTIVE: To determine if fetal urine production is affected by maternal meal ingestion in growth-restricted fetuses. METHODS: We studied 25 normal-growth fetuses in uncomplicated pregnancies and 15 growth-restricted fetuses, all after 30 weeks' gestation. Serial fetal bladder volume measurements were obtained at 2-3 minute intervals with ultrasonography 2 hours before and 2 hours after maternal breakfast. The hourly fetal urine production rate in each maternal state was calculated from the bladder volume measurements. The amniotic fluid index (AFI) and the pulsatility index of both umbilical and fetal middle cerebral arteries were also measured. RESULTS: Two of the 15 growth-restricted fetuses were excluded from analysis, one because it was anomalous and the other because it was not small for gestational age at birth. In the normal-growth fetuses, the hourly fetal urine production rate increased significantly after maternal breakfast (mean +/- standard deviation 30.2 +/- 11.7 versus 41.1 +/- 14.6 mL/hour, P < .001). In contrast, in the growth-restricted fetuses, the rate did not change after maternal breakfast (24.6 +/- 6.2 versus 24.9 +/- 5.7 mL/hour). Although the urine production rate before breakfast did not differ between groups, 2 hours after maternal breakfast it was significantly lower in the growth-restricted fetuses than in the control group (normal-growth) (P < .001). The AFI also was significantly lower in the growth-restricted fetuses than in the control group (15.0 +/- 3.5 versus 18.6 +/- 5.0 cm, P < .04). There were no significant differences in the pulsed Doppler studies. CONCLUSION: In contrast to normal-growth fetuses, maternal meal ingestion for growth-restricted fetuses does not increase fetal urine production. Decreased fetal urine production in the maternal fed state may lead to decreased amniotic fluid volume in growth-restricted fetuses without obvious hypoxia.

Amniotic Fluid↗
PubMed1996

Ultrasonographic prediction of lethal pulmonary hypoplasia: comparison of eight different ultrasonographic parameters.

OBJECTIVE: The aim of this study was to determine the usefulness of eight different ultrasonographic fetal parameters for predicting fetal pulmonary hypoplasia. STUDY DESIGN: Nomograms of eight different ultrasonographic fetal parameters were evaluated by studying uncomplicated single fetus pregnancies with well-established dates between 18 and 40 weeks of gestation. The eight parameters, which could reflect fetal lung mass, were as follows: thoracic circumference, thoracic area, thoracic area minus heart area, lung area, thoracic circumference/abdominal circumference ratio, thoracic area/heart area ratio, thoracic area minus heart area/thoracic area ratio and lung area/thoracic area ratio. The relative efficacy of the eight parameters was determined by studying 21 fetuses at high risk for development of lethal pulmonary hypoplasia and 30 fetuses with premature rupture of membranes within 1 week. RESULTS: The lung area (gestational age-dependent parameter) and the thoracic circumference/abdominal circumference (gestational age-independent parameter) ratio had the best diagnostic accuracy (sensitivity 81.3% and 90.5%, specificity 100% and 90.0%, positive predictive value 100% and 86.4%, negative predictive value 90.9% and 93.1%, respectively). There were significant linear relationships between lung weight and lung area and between the lung weight/body weight ratio and the thoracic circumference/abdominal circumference ratio. CONCLUSION: These data suggested that the application of lung area and the thoracic circumference/abdominal circumference ratio are clinically useful for the evaluation of fetal pulmonary hypoplasia.

Abdomen↗
PubMed1996

Hyperinsulinemia increases the risk of gestational hypertension.

OBJECTIVE: To determine whether hyperinsulinemia is related to gestational hypertension. METHODS: We measured the arterial blood pressure and the level of immunoreactive insulin (IRI) during a 75 g oral glucose tolerance test in a total of 84 pregnant women. Hyperinsulinemia was defined as a fasting IRI level > or = 9 IU/l, while gestational hypertension was defined as arterial blood pressure > or = 140/90 mmHg. RESULTS: The incidence of gestational hypertension was higher in the hyperinsulinemic group (n = 29) than in the control group (n = 55) (24.1% vs. 7.3%, respectively P < 0.05). After controlling for maternal age, parity, pre-pregnancy body mass index and the gestational age at the time of oral glucose tolerance test (OGTT), using a multiple regression model, the relative risk of developing gestational hypertension for a fasting insulin level was 1.19 (95% C.I., 1.03-1.38). CONCLUSION: Pregnant women with hyperinsulinemia are at increased risk of developing gestational hypertension.

Adult↗
PubMed1996

Olfactory evoked potentials produced by electrical stimulation of the olfactory mucosa.

We stimulated the olfactory mucosa electrically and elicited evoked potentials in rabbits. A bipolar stimulating electrode was placed on the olfactory region of the nasal mucosa via an anterior naris non-invasively. Evoked potentials were detected from the surface of a head. In most instances they were composed of triphasic negative-positive-negative peaks, the latencies of these peaks were about 25, 40, and 65 ms, respectively. This peak complex seemed to originate in the olfactory bulb. This method is non-invasive and is applicable to studying the olfactory system in animals and also in humans.

Animals↗
PubMed1996

Transvaginal color Doppler studies in gestational trophoblastic disease.

Three women with gestational trophoblastic disease were examined using transvaginal color Doppler at the initial diagnosis and after each course of chemotherapy. In all cases, the examination before chemotherapy revealed hypoechoic areas surrounded by irregular echogenic areas and numerous intramyometrial flow signals. Pulsed Doppler examination revealed a low pulsatility index (PI) in the uterine arteries. After the completion of chemotherapy, a decrease in the vascularity and increase in the PI of the uterine arteries were demonstrated in two cases. These findings were closely consistent with the decrease in serum levels of beta-human chorionic gonadotropin. However, in the patient who developed permanent arteriovenous communication, hypervascularity persisted and the PI of the uterine arteries remained low, even after clinical remission was achieved. The present study indicates that transvaginal color Doppler ultrasonography is useful for the evaluation of gestational trophoblastic disease, both at the time of diagnosis and after chemotherapy.

Adult↗
PubMed1996

Mouse/human sequence divergence in a region with a paternal-specific methylation imprint at the human H19 locus.

We have identified a region with characteristics of a paternal-specific methylation imprint at the human H19 locus. This region, extending from -2.0 kb upstream to the start of transcription, is heavily methylated in sperm and on the paternal allele in somatic cells. This methylation was preserved during pre-implantation. Structural analysis revealed the presence of CpG islands and a large direct repeat with a 400 bp sequence reiterated several times, but no significant sequence homology to the corresponding region of the mouse H19 gene. These findings could suggest a role for secondary DNA structure in genomic imprinting across the species, and they also present a puzzling aspect of the evolution of the H19 regulatory region in human and mouse.

Alleles↗
PubMed1996

Influence of serum follicle stimulating hormone to luteinizing hormone ratio during buserelin acetate-induced pituitary desensitization on ovarian response to exogenous gonadotrophins in an in-vitro fertilization and embryo transfer programme.

We investigated the effect of endogenous gonadotrophins during pituitary desensitization with gonadotrophin-releasing hormone agonist (GnRHa) on ovarian responsiveness or the outcome of in-vitro fertilization (IVF) and embryo transfer. The results of 67 women who participated in the IFV programme at Nagasaki University Hospital, Japan, were analysed retrospectively. All women received GnRHa from the third day of menstrual cycle, and ovarian stimulation with exogenous gonadotrophins was initiated when the serum oestradiol concentration decreased to < 30 pg/ml. The serum follicle stimulating hormone (FSH)/luteinizing hormone (LH) ratio, rather than serum FSH or LH concentrations during GnRHa-induced pituitary desensitization, showed a significant positive correlation with age and the total dose of exogenous gonadotrophins. The FSH/LH ratio also showed a significant negative correlation with oestradiol response and the number of retrieved oocytes, and was significantly lower in pregnant women compared with the non-pregnant group during pituitary desensitization. Our results indicate that, even under pituitary desensitization with GnRHa, the serum FSH/LH ratio influences individual ovarian responsiveness and the state of the intra-ovarian hormonal environment. Our results suggest that the FSH/LH ratio may be a useful clinical predictor of the ovarian response to exogenous gonadotrophins under pituitary desensitization.

Adult↗
PubMed1996

[Effect of prolonged intravenous ritodrine tocolysis on diurnal glucose profiles in pregnant women with normal carbohydrate tolerance].

Our purpose was to investigate an effect of prolonged intravenous ritodrine tocolysis on maternal carbohydrate metabolism in women with normal glucose tolerance. In patients with preterm labor, diurnal plasma glucose levels were measured both during the 24 hours after beginning the therapy (phase 1) and each day during over five days of continuous ritodrine tocolysis (phase 2). We also measured diurnal plasma glucose levels in normal pregnant women without any therapy (control group). In phase 1, in comparison with before therapy, a significant increase in the plasma glucose levels was observed with the highest level at 9 hours after starting ritodrine (146.4 +/- 31.6mg/dl). The higher plasma glucose levels persisted during phase 1. Although infusion rates were similar in both phases, maternal plasma glucose levels in phase 1 were significantly higher than in phase 2 (mean plasma glucose level, 128.1 +/- 21.3mg/dl vs. 92.7 +/- 11.6 mg/dl, p < 0.05; maximum plasma glucose level, 159.5 +/- 25.2mg/dl vs. 106.6 +/- 14.5mg/dl, p < 0.05). Diurnal glucose levels in phase 2 were similar to those in the control group. In phase 1, there seemed to be a dose-dependent relation between the ritodrine infusion rates and plasma glucose levels, but we did not find any relationship between them in phase 2. In conclusion, although hyperglycemia occurs during the initial phase of continuous ritodrine therapy (at least 24 hours), prolonged ritodrine infusion leads to normalization of the maternal plasma glucose levels.

Blood Glucose↗
PubMed1996

[Rapidly progressive T-cell angiocentric lymphoma with CD56+ phenotype involving bilateral orbits and skin in a patient with anti-HTLV-I antibody].

A 57-year-old woman was admitted to our hospital complaining of left exophthalmos in July, 1991. Biopsy specimen of a tumor in the left orbit suggested an inflammatory pseudotumor. The orbit was irradiated and the exophthalmos disappeared. During admission, an erythema was noted on her anterior chest wall. After discharge, right exophthalmos and generalized skin eruptions developed. The skin eruption on her anterior chest wall was histopathologically diagnosed as angiocentric lymphoma and she was readmitted. Since her serum was positive for anti-HTLV-I antibody, adult T-cell leukemia/lymphoma was suspected. Chemotherapy yielded limited relief of the right exophthalmos and transient fading of the skin eruptions. She died due to progression of the disease. Close examination of the skin eruption on the calf revealed that the lymphoma cells were CD56-positive immunohistochemically and electron microscopy revealed that they had large membrane-bound granules. Rearrangement of the T-cell receptor beta chain gene was observed. Incorporation of HTLV-I proviral DNA was not observed. Re-examination of the left orbital tumor confirmed the infiltration of these lymphoma cells. This is a rare case of T-cell lymphoma with NK cell phenotype involving orbits and skin, and showing a rapid clinical course.

CD56 Antigen↗
PubMed1995

Novel, potent, and orally active substance P antagonists: synthesis and antagonist activity of N-benzylcarboxamide derivatives of pyrido[3,4-b]pyridine.

A series of 4-phenylisoquinolone derivatives were synthesized and evaluated for NK1 (substance P) antagonist activity. Highly potent antagonists, 4-phenyl-3-isoquinolone-N-benzylcarboxamides (11), were discovered from the structure-activity relationship studies on the isoquinolone-urea lead 1a. Optimization of the activity in this series resulted in the development of 5-phenyl-6-pyrido[3,4-b]pyridine-N-benzylcarboxamides (30) which are highly potent orally active NK1 antagonists. Among the compounds synthesized, N-[3,5-bis(trifluoromethyl)benzyl]-7,8-dihydro-N,7-dimethyl-8-oxo-5- (substituted phenyl)-6-pyrido[3,4-b]pyridinecarboxamides (30a,f,g) showed excellent antagonist activities with IC50 values (in vitro inhibition of [125I]-BH-SP binding in human IM-9 cells) of 0.21-0.34 nM and ED50 values (in vivo inhibition of capsaicin-induced plasma extravasation in guinea-pig trachea, iv) of 0.017-0.030 mg/kg. These compounds exhibited significantly potent activity upon oral administration with ED50 values of 0.068-0.17 mg/kg. Conformational studies on 30g indicated that the two stable conformers of 30g are quite similar to those of CP-99,994.

Administration, Oral↗