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H Giles

Publications and source records attributed to H Giles.

52 records · Page 3Linked to original sources
PubMed1980

Qualitative real-time cross-sectional echocardiographic imaging of the human fetus during the second half of pregnancy.

In this study, we used high-resolution echocardiographic systems to investigate how early in pregnancy normal fetal cardiac anatomy could be noninvasively evaluated. Over a 2-year period, 84 of 88 fetuses were successfully imaged (27 were studied serially). Postnatal images of 73 were obtained during the newborn period. Estimated fetal age varied at initial examination from 19-41 weeks (mean +/- 0.5 weeks [+/- SEM]) of pregnancy. Estimated fetal weight using an ultrasound algorithm varied from 500-3100 g (mean 1580 +/- 80 g [+/- SEM]). To evaluate fetal cardiac anatomy, we reproduced commonly used cross-sectional views of the heart. The four-chamber and the short-axis great artery views have been most successful for cardiac evaluation in the fetus. These views could be obtained in 96% and 95% of the patients, respectively. With these views, cardiac chamber and valve structures, as well as two great arteries, could be imaged in detail. The ascending and descending aorta, as well as the aortic arch and vessels to the arms and head, were visualized in 87% of examinations, and the inferior and superior venae cavae were visualized in 76%. In two of three RH fetuses, changes in cardiac chambers compatible with hydrops fetalis were demonstrated. We examined all fetuses after birth and verified clinically (or noninvasively) that no cardiac malformations were present. It appears, however, that the diagnosis of major congenital heart defects should be possible before birth.

Aorta↗
PubMed1977

Intra-amniotic injection of thyroxine (T4Y to a human fetus. Evidence for conversion of T4 to reverse T3.

131I (150 mCi) was inadvertently given to a woman during week 10 to 11 of her gestation. When referred, fetal size was estimated at 31 to 32 weeks' gestation. Because of the potential risk of fetal hypothyroidism, an amniocentesis, with an injection of 500 mug of thyroxine, was performed weekly from week 33 until delivery. T4, T3, thyrodi-stimulating hormone (TSH), and rT3 were measured in amniotic fluid samples obtained at 33, 36, and 37 weeks. Maternal serum T4 was measured on the day of delivery. T4, T3, and TSH concentrations were measured in cord blood and during the neonatal period. The concentration of T4 in amniotic fluid (AF) was within the normal range at 32 weeks (prior to thyroxine); AF T3 and TSH were not detectable. The concentration of AF rT3 at 32 weeks also was normal (160 ng. per deciliter) and increased markedly after beginning intra-amniotic T4 injections; AF T4 increased modestly, but the AF T3 level remained unmeasurable. The concentration of T4 in cord serum obtained within 24 hours of the last amniotic fluid thyroxine injection, was in the hyperthyroid range and the TSH level was low. The cord serum T3 level was at the upper range of normal. The infant's serum T4 and T3 both increased during the first 24 hours. The male infant developed normally and serum T4 and TSH concentrations were normal at 4 months of age. The data indicate: (1) that T4 injected into AF is absorbed by the human fetus, (2) that AF rT3 concentration increases markedly after the AF T4 injection, whereas AF T3 levels do not increase, and (3) that the neonatal TSH surge is not entirely suppressed by hyperthyroid levels of cord serum T4.

Adult↗
PubMed1977

Detection of errors in methylmalonyl-CoA metabolism by using amniotic fluid.

We report a method for rapid prenatal detection of methylmalonic acidemia, consisting of measuring methylmalonly-CoA mutase (EC 5.4.99.2) activity in non-cultured amniotic cells and measuring the concentration of methylmalonate in the amniotic fluid. Immediate stabilization of the mutase activity in the non-cultured amniotic cell by its coenzyme adenosycobalamin, and use of methylmalonyl-CoA with high specific activity gives mutase activity comparable to that of cultured amniotic cells or normal fibroblasts. Consequently, findings of low mutase activity and a hight concentration of methylmalonate in the amniotic fluid allows accurate diagnosis of the vitamin B12-nonresponsive form of methylmalonic acidemia. These results can be obtained in two days. For the vitamin B12-responsive form, the correct diagnosis depends upon finding amniotic fluid methylmalonate, because cells from these patients will display normal methylmalony-CoA mutase activity after adenosylcobalamin is added. Problems in interpreting data on bloody samples and the limitations of the method are discussed.

Amniotic Fluid↗
PubMed1977

Development of sex-trait stereotypes among young children in the United Staes, England, and Ireland.

The Sex Stereotype Measure II (SSM II), a 32-item revision of the Williams, Bennett, and Best Sex Stereotype Measure, was developed to assess children's knowledge of conventional, sex-trait stereotypes defined by American university students. The procedure employed brief stories and human figure silhouettes which were individually administered to 5- and 8-year-old children in the United States, England, and Ireland and group administered to 11-year-olds in the United States. In the United States, knowledge of sex-trait stereotypes was found to develop in a linear fashion between the ages of 5 and 11, with more male traits than female traits being known at each age level. Cross-nationally, there was a high degree of similarity in the nature of the sex stereotypes being learned by the children in the 3 countries, although the rate of learning appeared slower among the Irish children. In all countries there was a clear progression in sex-stereotype learning from age 5 to age 8. English boys had greater knowledge of stereotypes than English girls, but this was not true in Ireland and the United States. Generally, knowledge of male stereotype traits appeared to develop earlier while knowledge of the female traits increased more rapidly between ages 5 and 8. The similarity in sex-stereotype learning in the 3 countries is discussed, and studies in progress in other countries of greater cultural diversity are noted.

Behavior↗
PubMed1976

A simple, rapid method for prenatal detection of defects in propionate metabolism.

Incorporation of radiolabel from propionate-1(-14)C into protein (TCA insoluble material) in fibroblasts or amniotic fluid cells, provides a rapid, simple means of detecting fetuses with inborn errors of propionate metabolism using small numbers of cells. Controls were easily differentiated from mutant lines over differing media pH conditions. This method was successfully used to diagnose correctly a normal fetus at risk for methylmalonic acidemia. This method can be used as an adjunct in diagnosis, but cannot replace direct enzyme analysis.

Amniotic Fluid↗
PubMed1975

Propionate metabolism in fetal livers of 15 to 19 weeks' gestation.

Extracts of hepatic tissue obtained from saline-induced abortuses were analyzed for methylmalonyl CoA carbonylmutase (MM) and propionyl CoA carboxylase (PC) activity. MM activity was similar to control values, which suggests that abortion material may be used to confirm the prenatal diagnosis of methylmalonic acidemia. Confirmation of a presumptive propionic acidemia diagnosis is more tenuous due to the instability of PC and the possibility that saline may induce PC activity.

Abortion, Induced↗