Maternal pregnancy-specific anxiety is associated with child executive function at 6-9 years age.

Because fetal brain development proceeds at an extremely rapid pace, early life experiences have the potential to alter the trajectory of neurodevelopment, which may increase susceptibility for developmental and neuropsychiatric disorders. There is evidence that prenatal maternal stress and anxiety, especially worries specifically related to being pregnant, influence neurodevelopmental outcomes. In the current prospective longitudinal study, we included 89 women for whom serial data were available for pregnancy-specific anxiety, state anxiety, and depression at 15, 19, 25, 31, and 37 weeks gestation. When the offspring from the target pregnancy were between 6 and 9 years of age, their executive function was assessed. High levels of mean maternal pregnancy-specific anxiety over the course of gestation were associated with lower inhibitory control in girls only and lower visuospatial working memory performance in boys and girls. Higher-state anxiety and depression also were associated with lower visuospatial working memory performance. However, neither state anxiety nor depression explained any additional variance after accounting for pregnancy-specific anxiety. The findings contribute to the literature supporting an association between pregnancy-specific anxiety and cognitive development and extend our knowledge about the persistence of this effect until middle childhood.

Antenatal betamethasone treatment has a persisting influence on infant HPA axis regulation.

OBJECTIVE: To examine the consequences of antenatal betamethasone (AB) exposure on postnatal stress regulation. STUDY DESIGN: Fourteen AB exposed infants born at 28-30 weeks' gestation were assessed in the NICU during postnatal week 1 and at 34 weeks postconception. Nine infants born at 34 weeks gestation without AB treatment were evaluated as a postconceptional age comparison group. Salivary cortisol, heart rate, and behavior were measured at baseline and in response to a heelstick blood draw. RESULTS: Repeated measures ANOVAs revealed that both groups displayed an increase in heart rate and behavioral distress in response to the stressor. The cortisol response, however, was blunted in AB-treated infants at both assessments. CONCLUSION: AB treatment has consequences for hypothalamic-pituitary-adrenal (HPA) axis regulation that persist for at least four to six weeks after birth, indicating that studies of long-term effects are warranted.

Antenatal glucocorticoid treatment is associated with diurnal cortisol regulation in term-born children.

Due to the rapid developmental changes that occur during the fetal period, prenatal influences can affect the developing central nervous system with lifelong consequences for physical and mental health. Glucocorticoids are one of the proposed mechanisms by which fetal programing occurs. Glucocorticoids pass through the blood-brain barrier and target receptors throughout the central nervous system. Unlike endogenous glucocorticoids, synthetic glucocorticoids readily pass through the placental barrier to reach the developing fetus. The synthetic glucocorticoid, betamethasone, is routinely given prenatally to mothers at risk for preterm delivery. Over 25% of the fetuses exposed to betamethasone will be born at term. Few studies have examined the lasting consequences of antenatal treatment of betamethasone on the regulation of the hypothalamic-pituitary-adrenal (HPA) axis. The purpose of this study is to examine whether antenatal exposure to betamethasone alters circadian cortisol regulation in children who were born full term. School-aged children prenatally treated with betamethasone and born at term (n=19, mean (SD)=8.1 (1.2) years old) were compared to children not treated with antenatal glucocorticoids (n=61, mean (SD)=8.2 (1.4) years old). To measure the circadian release of cortisol, saliva samples were collected at awakening; 30, 45, and 60min after awakening; and in the evening. Comparison children showed a typical diurnal cortisol pattern that peaked in the morning (the cortisol awakening response) and gradually decreased throughout the day. In contrast, children exposed to antenatal betamethasone lacked a cortisol awakening response and had a flatter diurnal slope (p's<0.01). These data suggest that antenatal glucocorticoid treatment may disrupt the circadian regulation of the HPA axis among children born at term. Because disrupted circadian regulation of cortisol has been linked to mental and somatic health problems, future research is needed to determine whether children exposed to antenatal synthetic glucocorticoids are at risk for poor mental and physical health.

Cortisol and social stressors in children with fragile X: a pilot study.

Evidence of neuroendocrine dysfunction, behavioral features of social anxiety and avoidance, and neuroanatomical abnormalities suggest that abnormal hypothalamic-pituitary-adrenal (HPA) function may be a component of the fragile X (fra X) syndrome. In this preliminary study, salivary cortisol levels of males (n = 8, mean age = 13.5 yr) and females (n = 7, mean age = 13.9 yr) with the fra X full mutation were studied for 3 days. Day 1 was an experimental day, during which subjects experienced a Social Stressor task midmorning. Days 2 and 3 were routine days, during which the subjects were engaged in their typical activities. Saliva samples were collected before breakfast, lunch, dinner, and bedtime. On the experimental day, the prelunch sample collection occurred 30 and 90 minutes after the Social Stressor task. Compared with children's norms, the combined group of males and females with fra X had significantly higher cortisol levels in the prelunch and the prebedtime samples for the routine days. Comparisons between the two fra X groups for the experimental day revealed similar diurnal patterns for cortisol level. However, compared with females with fra X, males with fra X had significantly higher cortisol levels at two points during the day: 30 minutes after the social stressor and at bedtime. These preliminary data suggest that individuals with fra X have abnormal HPA function. Understanding the relations among HPA dysfunction, abnormalities in brain structure and/or function, and maladaptive behavior and cognition in fra X could inform the design of early interventions using pharmacological or environmental measures designed to normalize neuroendocrine function.

Modeling tongue surface contours from Cine-MRI images.

This study demonstrated that a simple mechanical model of global tongue movement in parallel sagittal planes could be used to quantify tongue motion during speech. The goal was to represent simply the differences in 2D tongue surface shapes and positions during speech movements and in subphonemic speech events such as coarticulation and left-to-right asymmetries. The study used tagged Magnetic Resonance Images to capture motion of the tongue during speech. Measurements were made in three sagittal planes (left, midline, right) during movement from consonants (/k/, /s/) to vowels (/i/, /a/, /u/). MR image-sequences were collected during the C-to-V movement. The image-sequence had seven time-phases (frames), each 56 ms in duration. A global model was used to represent the surface motion. The motions were decomposed into translation, rotation, homogeneous stretch, and in-plane shear. The largest C-to-V shape deformation was from /k/ to /a/. It was composed primarily of vertical compression, horizontal expansion, and downward translation. Coarticulatory effects included a trade-off in which tongue shape accommodation was used to reduce the distance traveled between the C and V. Left-to-right motion asymmetries may have increased rate of motion by reducing the amount of mass to be moved.

Patterns of fetal heart rate response at ∼30 weeks gestation predict size at birth.

There is evidence that fetal exposure to maternal stress is associated with adverse birth outcomes. Less is known about the association between fetal responses to a stressor and indicators of fetal maturity and developmental outcomes. The purpose of the present study was to determine whether fetal heart rate (FHR) patterns in response to a startling stimulus at ∼30 weeks of gestation were associated with gestational age at birth and birth weight. FHR was measured in 156 maternal-fetal dyads following a vibroacoustic stimulus. All pregnancies were singleton intrauterine pregnancies in English-speaking women who were primarily married, middle class, White and at least 18 years of age. Group-based trajectory modeling identified five groups of fetuses displaying distinctive longitudinal trajectories of FHR response to the startling stimulus. The FHR group trajectories were significantly associated with birth weight percentile (P < 0.01) even after controlling for estimated fetal weight at the time of assessment and parity, which are the known factors influencing birth weight (P < 0.01). Post hoc analyses indicated that two groups accounted for the association between FHR patterns and birth weight. The group (n = 23) with the lowest birth weight exhibited an immediate FHR deceleration followed by an immediate acceleration that does not recover. An FHR pattern characterized by immediate and fast acceleration to the peak and a slow discovery to baseline was associated with the highest birth weight. This is the first direct evidence showing that low birth weight and the resulting neurological consequences may have their origins in early fetal development.

Effect of prenatal glucocorticoid treatment on size at birth among infants born at term gestation.

OBJECTIVE: To determine whether prenatal treatment with a single course of glucocorticoids (GCs) affects size at birth among full-term infants independent of fetal size before GC administration or exposure to preterm labor (PTL). STUDY DESIGN: In all, 105 full-term infants were recruited into three study groups (30 GC treated; 60 controls matched for gestational age (GA) at birth and sex; and 15 PTL controls without GC exposure). Size of the infants was estimated before treatment using two-dimensional (2D) ultrasound and by direct measurement at birth. RESULTS: Length, weight and head circumference at birth were smaller among GC-treated infants compared with matched controls (P's<0.01), although fetal size did not differ before treatment (P's>0.2). Exposure to PTL did not account for this effect. CONCLUSIONS: Prenatal treatment with a single course of GCs was associated with a reduction in size at birth among infants born at term gestation. This effect cannot be explained by differences in fetal size before treatment or exposure to PTL.

A head and transducer support system for making ultrasound images of tongue/jaw movement.

A head and transducer support system (HATS) was developed for use in ultrasound imaging of tongue movement. Ultrasound is an imaging technique that captures tongue motion during speech and thus has great appeal as a tool for speech research. However, because ultrasound systems are designed for clinical use, the transducer is hand-held and it is almost impossible to hold it completely steady under the chin when collecting tongue data. A system was needed to fix the head and support the transducer under the chin in a known position without disturbing speech. The HATS system was designed, constructed, and modified to provide valid, reliable tongue movement data by (1) immobilizing the head and (2) positioning the ultrasound transducer in a known relationship to the head.

Use of trinitrobenzene as a nitrogen source by Pseudomonas vesicularis isolated from soil.

An aerobic Gram-negative bacterium identified as Pseudomonas vesicularis was isolated from soil contaminated with 2,4, 6-trinitrotoluene (TNT) and 1,3,5-trinitrobenzene (TNB). This bacterium used TNB as the sole source of nitrogen. The TNB was metabolized within 80 h of incubation. The major metabolites produced were dinitroaniline,dinitrobenzene (DNB), nitroaniline, nitrobenzene (NB), and ammonia. The concentrations of DNB and NB produced in the culture medium were nearly stoichiometric. The ammonia concentration in the culture medium increased during the course of incubation. The end product of TNB metabolism was NB,which did not undergo further degradation even after long incubation time. This bacterium could be used in a syntrophic culture system with other NB-degrading bacteria to remove TNB completely from soil and water at contaminated sites.

The start of a new school year: individual differences in salivary cortisol response in relation to child temperament.

Noon and evening salivary cortisol levels were examined in 70 elementary school children during the 1st week of a new school year. Samples were obtained on the 1st and 5th days of school and on weekend days. Delta cortisol scores were created to measure the change in children's levels on initial school days relative to weekend days. Temperament was assessed using Rothbart's Child Behavior Questionnaire, a parent report instrument. The three dimensions of surgency or extroversion, negative affectivity, and effortful control were examined. Positive correlations were obtained with Day 1 delta cortisol for negative affectivity and Day 5 delta cortisol for surgency. Contrary to the expectation that internalizing aspects of temperament (shyness, fearfulness) would be associated with larger increases in cortisol to the novelty and challenge of a new school year, these data indicate that larger increases in cortisol were observed in more extroverted children.

Modeling the motion of the internal tongue from tagged cine-MRI images.

A new technique, tagged Cine-Magnetic Resonance Imaging (tMRI), was used to develop a mechanical model that represented local, homogeneous, internal tongue deformation during speech. The goal was to infer muscle activity within the tongue from tissue deformations seen on tMRI. Measurements were made in three sagittal slices (left, middle, right) during production of the syllable /ka/. Each slice was superimposed with a grid of tag lines, and the approximately 40 tag line intersections were tracked at 7 time-phases during the syllable. A local model, similar to a finite element analysis, represented planar stretch and shear between the consonant and vowel at 110 probed locations within the tongue. Principal strains were calculated at these locations and revealed internal compression and extension patterns from which inferences could be drawn about the activities of the Verticalis, Hyoglossus, and Superior Longitudinal muscles, among others.