Daily relationships between fetal and maternal heart rates at 38 to 40 weeks of pregnancy.
Explore the source record for details and available documents.
Circadian Rhythm↗
Biomedical subjects
B Richardson
Publications and source records attributed to B Richardson.
Effects of synthetic glucocorticoid administration on human fetal breathing movements at 34 to 35 weeks' gestational age.
Fetal breathing movements were measured in six women who had received exogenous glucocorticoids throughout pregnancy and in whom the endogenous circadian rhythm in cortisol was absent or had been suppressed. Studies were performed for 24-hour observation periods while women received prednisone and then one week later on the same women after equivalent doses of dexamethasone. Fetal breathing movements occurred 29.9% +/- 1.9% of the time in the prednisone-treated group and this was not changed in the same fetuses after dexamethasone treatment. There was a significant increase in the percentage of time spent making breathing movements during the second and third hours following breakfast, lunch, and dinner (P less than 0.001). A fourth peak in fetal breathing activity occurred in the late evening and seemed to be related to the time of the evening glucocorticoid medication. These data were compatible with the hypothesis that maternal glucocorticoid concentrations may influence patterns of fetal breathing movements at 34 to 35 weeks' gestational age.
Blood Glucose↗
Loss of diurnal rhythm in plasma estrone, estradiol, and estriol in women treated with synthetic glucocorticoids at 34 to 35 weeks' gestation.
In order to examine the effect of endogenous rhythms in fetal and/or maternal adrenal activity on diurnal changes in plasma estrone (E1), estradiol (E2), estriol (E3), and progesterone (P) in women at 34 to 35 weeks' gestation, we measured these steroids in a group of six women in whom the endogenous circadian rhythm in cortisol was absent or had been suppressed by treatment with exogenous synthetic glucocorticoids. All steroids were suppressed, and no diurnal rhythms in E1, E2, E3 or P were found. Suppression of cortisol and estrogens was greater after dexamethasone (Dx) than after a glucocorticoid-equivalent dosage of prednisone (Pd). Loss of the maternal estrogen rhythms seen in normal patients is consistent with the suggestion that such rhythms may be attributable to diurnal changes in maternal and/or fetal adrenal output of potential precursors. The differences in cortisol and estrogen concentrations after Dx and Pd may indicate dissociation of the glucocorticoid (hyperglycemic) and adrenocorticotropic hormone-suppressing activities of these compounds.
Adrenal Glands↗
Effects of external physical stimulation on fetuses near term.
Measurements were made in 17 healthy pregnant women between 36 and 42 weeks' gestational age 90 minutes before and after a standard physical stimulus. The mean fetal heart rate was 138 +/- 0.4 bpm; the median value of the 5-minute standard deviation of successive heartbeat intervals was 30.3 msec, and the percentage of time spent making gross fetal body movements was 11.1% +/- 0.4%. These measurements did not change following stimulation of fetuses. Fetal breathing movements diminished over the 180-minute observation period but did not appear to be changed by fetal stimulation. During studies, periodic increases separated by periodic decreases in fetal heart rate, fetal heart rate variability, gross fetal body movements, and fetal breathing movements were measured, and these changes did not seem to be related to external stimulation of fetuses. Periodic changes in these measurements may have been related to underlying patterns of fetal behavior but were not usually influenced by external physical stimulation of fetuses.
Female↗
Prolactin status in chronic nephropathy in the rat.
Decreased specific prolactin binding to kidney membrane preparations, and an upward trend in serum prolactin levels were observed concomitantly with the onset of chronic progressive nephropathy im male rats of the OFA Sandoz SPF strain. Females of the same strain developed a less severe form of the disease at a later age, but failed to show the changes in prolactin status seen in male rats. Nephropathy in both male and female animals was associated with morphological abnormalities of a predominantly tubular nature, but was not associated with development of renal failure as indicated by serum urea and creatinine levels. Possible mechanisms for the observed alterations in prolactin status are discussed.
Aging↗
Utility of the fluorescent antinuclear antibody test in a single patient.
The literature on the fluorescent antinuclear antibody (FANA) test, commonly used in diagnosing systemic lupus erythematosus, was analyzed. The specificity of the test reported in early descriptive studies is much greater than the value obtained when the test is used in clinical practice. The probability of systemic lupus erythematosus in a specific patient was determined when different numbers of the classification criteria developed by the American Rheumatism Association are present. The predictive value of a positive or negative FANA test result was calculated using different pretest probabilities based on clinical criteria. The marginal benefit of the FANA test was determined as minimal at points of very large and very small pretest probability of systemic lupus erythematosus, and as maximal when five clinical criteria are present.
Antibodies, Antinuclear↗
Self recognition in the regulation of immune reactivity.
Explore the source record for details and available documents.
Animals↗
Gently does it for a mixed-sex ward.
Explore the source record for details and available documents.
Female↗
A definition of human fetal apnea and the distribution of fetal apneic intervals during the last ten weeks of pregnancy.
Fetal breathing movements were studied over 24-hour observation periods for a total of 744 hours in 31 healthy pregnant women at 30 to 39 weeks' gestational age. An analysis of 165,786 breath-to-breath intervals in eight fetuses demonstrated that 97% of breath-to-breath intervals were less than 6 seconds in duration. It was concluded that a breath-to-breath interval of 6 seconds or more is a rational definition of fetal apnea during the last 10 weeks of pregnancy. An analysis of intervals during which time no fetal breathing activity occurred in the 31 fetuses demonstrated that prolonged episodes of apnea were distributed in a similar fashion at different gestational ages. The longest periods of apnea were 65 minutes at 30 to 31 weeks, 105 minutes at 34 to 35 weeks, and 120 minutes at 38 to 39 weeks. No periods of apnea of more than 45 minutes were measured during the second and third hours following maternal meals. A useful strategy for recognition of significant fetal apnea would be to make observations during the second and third hours following maternal meals when apneic lengths greater than 45 minutes were not observed in this highly selected group of normal fetuses.
Apnea↗
Circadian rhythms in maternal plasma cortisol and estriol concentrations at 30 to 31, 34 to 35, and 38 to 39 weeks' gestational age.
In order to examine the relationship between circadian rhythms in different steroids, cortisol and estriol were measured by radioimmunoassay in maternal venous plasma taken at 30- to 60-minute intervals over 24 hours from nine healthy women at 30 to 31, 11 at 34 to 35, and 10 at 38 to 39 weeks' gestation. Maternal cortisol was maximal at 0730 to 0830 hours and fell significantly to its lowest concentration between 1830 and 0130 hours. At 30 to 31 and 34 to 35 weeks there was a significant circadian rhythm in estriol concentrations which was inversely related to the circadian rhythm in cortisol. At 38 to 39 weeks mean estriol concentrations were significantly higher than those at 30 to 31 and 34 to 35 weeks but there was no significant circadian pattern. We concluded that there is an inverse relationship between maternal cortisol and estriol at 30 to 31 and 34 to 35 weeks, which would be consistent with a maternal effect on fetal adrenal function. The increase in mean concentration and absence of circadian rhythm in maternal plasma estriol at term might suggest an additional positive stimulus to fetal adrenal function. The existence of patterns in maternal estriol concentrations must be taken into account in the u;se of sequential measurements of this hormone during the last 10 weeks of pregnancy.
Circadian Rhythm↗
Early intervention with Down syndrome children: follow-up report.
This report compares developmental milestones and current intellectual and adaptive functioning of 20 children with Down syndrome who participated in an early intervention program with those of 53 noninstitutionalized children with Down syndrome who did not experience such a program. The children in the former group generally showed earlier acquisition of motor and self-help skills and significantly higher intelligence quotients and social quotients at three to six years of age. Because of certain variables that could not be rigorously controlled in this type of program, the higher functioning cannot be clearly attributed to early intervention. These findings nevertheless are consistent with the hypothesis that early intervention has a beneficial effect and should provide encouragement for further studies.
Child↗
Diurnal changes in maternal plasma oestrone and oestradiol at 30 to 31, 34 to 35 and 38 to 39 weeks gestational age.
Diurnal changes in the concentrations of oestrone (E1) and oestradiol (E2) in maternal peripheral plasma have been measured in samples of blood taken at one hour intervals from women at 30 to 31, 34 to 35 and 38 to 39 weeks of pregnancy. There was a significant effect of time of sampling on the plasma concentration of E1 at all stages of gestation, and circadian changes in the levels of E1 were apparent at 34 to 35 and 38 to 39 weeks. Peak values were measured around 0830 to 0930 hours, and troughs occurred between 0130 and 0530 hours. Significant effects of time of sampling on the plasma concentration of E2 were found at 34 to 35 and 38 to 39 weeks of pregnancy; night-time concentrations were lower than the peak values at 0730 to 0830 hours. The relation of these changes to the circadian rhythms in the concentrations of cortisol and oestriol in maternal plasma are discussed.
Circadian Rhythm↗
Patterns of human fetal breathing during the last 10 weeks of pregnancy.
Continuous measurements of human fetal breathing movements and gross fetal body movements were made with an ultrasonic real-time scanner for periods of 24 houro 31 weeks' gestation, a significant increase in fetal breathing movements occurred during the second and third hours after meals; this pattern apparently followed an increase in maternal plasma glucose concentrations. At 38 to 39 weeks' gestation, fetal breathing movements increased during the second and third hours after breakfast, but the troughs seen before lunch and supper at 30 to 31 weeks' gestation were not present. Fetal breathing movements diminished over the day and reached a minimum between 1900 and 2400 hours. Fetal breathing activity increased in both groups between 0400 and 0700 hours while mothers were asleep; this was not related to an increase in maternal glucose concentrations. Absence of fetal breathing movements was observed for up to 122 minutes in this analysis of 480 hours in 20 patients. These data show that much more information must be obtained on factors that normally influence fetal breathing activity. Only then can research strategies be suggested for clinical evaluation of the usefulness of fetal breathing movements in the assessment of fetal health.
Blood Glucose↗
Circadian rhythms in maternal plasma cortisol, estrone, estradiol, and estriol at 34 to 35 weeks' gestation.
In order to examine the relationship between circadian rhythms in different steroids, cortisol (F), estrone E1), estradiol (E2), and estriol (E3) were measured by radioimmunoassay in maternal venous plasma taken at 30 to 60-minute intervals over 24 hours from 11 healthy women at 34 to 35 weeks' gestation. Maternal F was maximal at 0730 hours and fell significantly to its lowest concentration at 0230 hours. Maretnal E3 was lowest between 1000 and 1130 hours and rose significantly to maximal values between 2230 and 0030 hours. Maternal E1 was maximal between 1000 and 1130 hours and showed a significant decrease to reach its lowest concentration at 0430 to 0630 hours. No significant circadian change was measured in uncorrected concentrations of E2. We conclude that there is an inverse relationship between maternal F and E3, which would be consistent with a maternal effect on fetal adrenal function, and the existence of circadian rhythms in F, E1, E2, and E3 must be taken into account in clinical investigations of these hormones during pregnancy.
Circadian Rhythm↗
Human fetal breathing activity during electively induced labor at term.
Human fetal breathing movements were measured during the first stage of electively induced labor in 20 healthy term pregnancies. Fetuses made breathing movements 25.6% of the time during a 1 hour control period and breathing decreased significantly to 8.3% during latent-phase labor and further decreased to 0.8% during active labor (P less than 0.001). Patterns of increased fetal breathing activity accompanied by increased gross fetal body movements and increased fetal heart rate variability for periods of 20 to 60 minutes out of every 1.0 to 1.5 hours were observed, and the intermittent patterns of increased body movement and heart rate variability continued throughout the first stage of labor despite the decrease in fetal breathing activity during latent- and active-phase labor. It will be important to account for rest activity patterns when interpreting variability of heart rate during labor. The absence of fetal breathing activity during electively induced labor at term is not a clinical indicator of fetal ill health.
Anesthesia, Epidural↗
Differential selectivity of several barbiturates on experimental seizures and neurotoxicity in the mouse.
Six barbiturates with diverse time-action characteristics--thiopental, pentobarbital, butabarbital, phenobarbital, diphenylbarbiturate, and barbital--were evaluated for "anticonvulsant" and "neurotoxic" effects. For the former, the MES test, clonic seizures induced by pentylenetetrazol, 90 mg/kg, s.c., and maximal seizures produced by pentylenetetrazol, 200 mg/kg, s.c., were employed. For the latter, we used a rotorod technique. Time to peak activity in the MES test was employed as the time for other tests. Pentobarbital required at least neurotoxic doses to produce substantial "anticonvulsant" activity, its protective index ranging from 0.79 to 0.98 in the three tests. Among the drugs tested, phenobarbital and diphenylbarbiturate exhibited the most favorable protective indices, ranging from 2.71 to 3.41 for phenobarbital and from 3.85 to 5.0 for diphenylbarbiturate. Barbital, another drug with a prolonged duration of action, exhibited a range from 0.84 to 2.81. Although a prolonged duration of action is an important characteristic for antiepileptic activity, this property does not confer per se a favorable protective index.
Animals↗
Patterns of human fetal breathing activity at 34 to 35 weeks' gestational age.
Continuous measurements of human fetal breathing movements at 34 to 35 weeks' gestational age were made with an ultrasonic real-time scanner for periods of 24 hours in 11 women. A significant increase occurred in fetal breathing activity during the second and third hour following meals and this pattern apparently followed an increase in maternal plasma glucose concentration. There was a prolonged significant increase in fetal breathing activity between 0100 and 0700 hours. Increases in human fetal breathing activity accompanied by increased gross fetal body movements occurred for periods of 20 to 60 minutes out of every 1.0 to 1.5 hours of observation time. It was concluded that the percentage of time spent breathing by normal fetuses was related to time of day and maternal meals. The alternating changes of fetal activity and inactivity observed may represent biologic changes of sleep state in the human fetus in utero at 34 to 35 weeks' gestational age. It will be important to account for these three patterns of fetal breathing activity in clinical studies which examine the usefulness of fetal breathing movements in assessing fetal health.
Abdominal Muscles↗
Effects of human maternal venous plasma glucose concentrations on fetal breathing movements.
Human fetal breathing movements were studied following the maternal ingestion of either a 50 Gm. oral glucose load or an equal volume of water in 22 healthy women with uncomplicated pregnancies at 32 to 34 weeks' gestation. The percentage of time spent breathing in fetuses of glucose-treated mothers increased from 23.2 +/- 2.2 per cent during the control period to a maximum of 58.9 +/- 5.2 per cent at 105 minutes following the oral glucose load (p less than 0.01) which was one hour following the peak maternal plasma glucose concentration. No similar increase in maternal glucose concentrations or percentage time spent breathing occurred in patients receiving water. Fetal breathing movements were observed in 97 per cent of the 15 minute periods during the second and third hour after maternal ingestion of a 50 Gm. oral glucose load. It was concluded that maternal carbohydrate intake two hours prior to fetal breathing observations should be documented to permit adequate interpretation of fetal breathing activity.
Administration, Oral↗