Skip to main content
eScholarship
Open Access Publications from the University of California

Scholarly Works (25 results)

  • Article
  • Peer Reviewed
UC Irvine Previously Published Works (2002)
Self-injurious behavior (SIB) is an untreatable and often life-threatening problem among individuals with developmental disorders, especially those diagnosed with autism. Functioning, relationships and processing of the proopiomelanocortin (POMC) system are "uncoupled" in subgroups of self-injuring individuals resulting in different ratios of ACTH and opioids in the bloodstream, particularly under conditions of stress. In this study, relations between SIB and POMC were evaluated in a multi-year study of the largest prospective sample studied to date. Observations were collected on palmtop computers for 45 treatment-resistant patients who exhibited chronic SIB. Behavior of each subject was observed in natural settings without disruption or intrusion, for continuous, 2.5-h periods, two times a day (morning and afternoon), 4 days a week for two consecutive weeks, for a total of 40 h/subject. Blood was collected in the morning, late afternoon and immediately after an SIB episode on two separate occasions separated by at least 6 months. Levels of beta-endorphin (beta E) and ACTH were assayed by RIA. We discovered that the SIB was the best predictor of subsequent SIB. Moreover, the majority of subjects exhibited this contagious pattern of SIB. Levels of POMC fragments were reliable over a 6- to 9-month period. Subjects exhibiting POMC disregulation characterized by high morning levels of beta E had the highest transitional probabilities of SIB (i.e. contagious patterns; F=8.17, P<0.01). These findings suggest that subjects with "contagious" SIB may represent a behavioral phenotype associated with disregulated expression of the POMC gene.
    Cover page: Disregulation of proopiomelanocortin and contagious maladaptive behaviorCreative Commons 'BY' version 4.0 license
    • Article
    • Peer Reviewed
    UC Irvine Previously Published Works (2005)

    Objective: This study examined women’s mood responsiveness on work and off days during different phases of the menstrual cycle. Methods: Self reports of negative, positive, and energy dimensions of mood were obtained throughout the day on two work and two off days during the luteal and follicular phases of the menstrual cycle in 203 women nurses. Individual differences in daytime and nighttime epinephrine, norepinephrine, and cortisol were assessed. Results: High daytime norepinephrine, epinephrine, and cortisol levels were associated with higher ratings of stress and tired, and with lower ratings of happy. Phase of the menstrual cycle and the day factor (work day, off day) were also associated with mood differences, and the direction of the effects depended on hormone levels and hormone sampling period. Conclusion: The experience of moods is affected by arousal-related interaction of hormone levels with phase of the menstrual cycle and occupational stress.

      Cover page: Moods in everyday situations: Effects of menstrual cycle, work, and stress hormones
      • Article
      • Peer Reviewed
      UC Irvine Previously Published Works (2000)
      Proopiomelanocortin (POMC) contains several interesting, behaviorally active peptides. Release patterns of these fragments have been related to bizarre episodes of self-injurious behavior (SIB) among autistic individuals. Moreover, elevation in beta-endorphin (betaE) but not ACTH levels was associated with a positive response to an acutely administered, centrally acting opioid blocker among autistic individuals exhibiting SIB. In the present study, POMC fragments were measured in 12 self-injurious patients before and after long term (3 month) treatment with an opiate blocker naltrexone (NTX). POMC fragments were sampled from blood collected at the beginning of the baseline and placebo-controlled treatment phases of the study. Results indicated that the co-release (coupling) of POMC fragments were stable over time and the profile of POMC fragments in plasma predicted the effectiveness of a CNS acting drug in autistic subjects who self-injure.
        Cover page: Uncoupling of proopiomelanocortin (POMC) fragments is related to self-injuryCreative Commons 'BY' version 4.0 license
        • Article
        • Peer Reviewed
        UC Irvine Previously Published Works (2008)
        Elevation in placental corticotropin-releasing hormone (pCRH) during the last trimester of pregnancy has been associated with an increased risk for preterm delivery. Less is known about the consequences for the human fetus exposed to high levels of pCRH early in pregnancy. pCRH levels were measured in 138 pregnant women at least once at 15, 20 and 25 weeks of gestation. At 25 weeks of gestation, fetal heart rate (FHR) responses to a startling vibroacoustic stimulus (VAS) were recorded as an index of maturity. pCRH levels at 15 weeks of gestation, but at no later point, predicted FHR responses to the VAS. Fetuses exposed to the lowest concentrations of pCRH at 15 weeks of gestation exhibited a distinguishable response to the VAS, whereas fetuses exposed to higher levels of pCRH did not respond. The findings suggest that exposure to low levels of pCRH early in gestation may be optimal and associated with a response pattern indicating greater maturity.
          Cover page: Low Levels of Corticotropin-Releasing Hormone during Early Pregnancy Are Associated with Precocious Maturation of the Human FetusCreative Commons 'BY' version 4.0 license
          • Article
          • Peer Reviewed
          UCLA Previously Published Works (2007)

          OBJECTIVE: This study examined women's mood responsiveness associated with patterns of stress hormone levels in everyday situations. METHODS: Self-reports of negative, positive, and energy dimensions of mood were obtained from 203 nurses throughout the day on a workday and on an off-work day during the luteal and follicular phases of the menstrual cycle. Individual differences in daytime norepinephrine and cortisol were assessed. RESULTS: Patterns of norepinephrine and cortisol levels were associated with ratings of the following moods: tired, sad, and happy. Phase of the menstrual cycle and the day factor (workday, off-work day) modified the association of mood ratings and stress hormone patterns. CONCLUSION: The experience of negative mood is associated with both hypoarousal and hyperarousal conditions. A homeostatic arousal-related concept of mood regulation is discussed.

            Cover page: Moods in everyday situations: effects of combinations of different arousal-related factors.
            • Article
            • Peer Reviewed
            UC Irvine Previously Published Works (2006)
            The purposes of this study were to determine the intervals when placental corticotrophic-releasing hormone (CRH) was most responsive to maternal cortisol. A sample of 203 women each were evaluated at 15, 19, 25 and 31 weeks gestation and followed to term. Placental CRH and maternal adrenocorticotropin hormone (ACTH), B-endorphin and cortisol were determined from plasma. CRH levels increased faster and were higher in women who delivered preterm compared with women who delivered at term (F3,603 = 5.73, p < .001). Simple effects indicated that CRH levels only at 31 weeks predicted preterm birth (F1,201 = 5.53, p = .02). Levels of cortisol were higher in women who delivered preterm at 15 weeks gestation (F1,201 = 4.45, p = .03) with a similar trend at 19 weeks gestation. Hierarchical regression suggested that the influence on birth outcome of maternal cortisol early in pregnancy was mediated by its influence on placental CRH at 31 weeks. Elevated cortisol at 15 weeks predicted the surge in placental CRH at 31 weeks (R = .49, d.f. = 1,199, Fchange = 61.78, p < .0001). Every unit of change in cortisol (microg/dl) at 15 weeks was associated with a 34 unit change of CRH (pg/ml) at 31 weeks. These findings suggested that early detection of stress signals by the placenta stimulated the subsequent release of CRH and resulted in increased risk for preterm delivery.
              Cover page: Elevated maternal cortisol early in pregnancy predicts third trimester levels of placental corticotropin releasing hormone (CRH): Priming the placental clockCreative Commons 'BY' version 4.0 license
              • Article
              • Peer Reviewed
              UC Irvine Previously Published Works (2005)
              During pregnancy corticotropin-releasing hormone (CRH) is released into maternal and fetal circulation from the placenta. Elevated concentrations of placental CRH are associated with spontaneous preterm birth, but the consequences for infant development, independent of birth outcome, are unknown. In this study, the effects of placental CRH on infant temperament were examined in a sample of 248 full-term infants. Maternal blood samples were collected at 19, 25 and 31 weeks of gestation for CRH analysis. Infant temperament was assessed with measures of fear and distress at 2 months of age. Infants of mothers with low CRH at 25 weeks of gestation scored lower in fear and distress at 2 months. CRH at 19 and 31 weeks' gestation was not significantly associated with measures of infant temperament, suggesting the possibility that there is a sensitive period for its effects. These data suggest that prenatal exposure to CRH may exert influences that persist into the postnatal period.
                Cover page: Corticotropin-Releasing Hormone during Pregnancy Is Associated with Infant TemperamentCreative Commons 'BY' version 4.0 license
                • Article
                • Peer Reviewed
                UC Irvine Previously Published Works (2007)

                Background

                Accumulating evidence indicates that prenatal maternal and fetal processes can have a lasting influence on infant and child development. Results from animal models indicate that prenatal exposure to maternal stress and stress hormones has lasting consequences for development of the offspring. Few prospective studies of human pregnancy have examined the consequences of prenatal exposure to stress and stress hormones.

                Method

                In this study the effects of prenatal maternal psychosocial (anxiety, depression, and perceived stress) and endocrine (cortisol) indicators of stress on infant temperament were examined in a sample of 247 full-term infants. Maternal salivary cortisol and psychological state were evaluated at 18-20, 24-26, and 30-32 weeks of gestation and at 2 months postpartum. Infant temperament was assessed with a measure of negative reactivity (the fear subscale of the Infant Temperament Questionnaire) at 2 months of age.

                Results

                Elevated maternal cortisol at 30-32 weeks of gestation, but not earlier in pregnancy, was significantly associated with greater maternal report of infant negative reactivity. Prenatal maternal anxiety and depression additionally predicted infant temperament. The associations between maternal cortisol and maternal depression remained after controlling for postnatal maternal psychological state.

                Conclusions

                These data suggest that prenatal exposure to maternal stress has consequences for the development of infant temperament.
                  Cover page: Prenatal Exposure to Maternal Depression and Cortisol Influences Infant TemperamentCreative Commons 'BY' version 4.0 license
                  • Article
                  • Peer Reviewed
                  UC Irvine Previously Published Works (2007)
                  Significant ethnic disparities exist in reproductive outcomes. A potential contributing factor may be the functioning of the hypothalamic-pituitary-adrenal (HPA) axis and placenta during pregnancy. In the present study, levels of cortisol, ACTH and CRH were determined longitudinally from the plasma of 310 African American, Hispanic and non-Hispanic White women at 18-20, 24-26 and 30-32 weeks' gestation. During pregnancy, African American women exhibited lower levels of cortisol than non-Hispanic women and higher levels of ACTH than Hispanic women. The trajectory of CRH increase also differed by ethnicity, with African Americans exhibiting the lowest levels both early and late in pregnancy. Higher levels of cortisol at 18-20 weeks were associated with higher levels of CRH at 30-32 weeks among the African American and Hispanic women, but not among non-Hispanic women. Ethnic differences persisted when adjusting statistically for sociodemographic and biomedical factors. The findings are consistent with the possibility that ethnic disparities in adverse birth outcomes may be due, in part, to differences in HPA axis and placental function.
                    Cover page: Ethnic differences in adrenocorticotropic hormone, cortisol and corticotropin-releasing hormone during pregnancyCreative Commons 'BY' version 4.0 license
                    • Article
                    • Peer Reviewed
                    UC Irvine Previously Published Works (2003)
                    Maternal peptides from the hypothalamic-pituitary-adrenal (HPA) axis rise during human pregnancy. The effects of circulating maternal adrenocorticotropin (ACTH) and beta-endorphin (BE) on human fetal behavior was determined in 135 women during their 32nd week of gestation. Fetal behavior was measured by assessing heart rate habituation to a series of repeated vibroacoustic stimuli. Individual differences in habituation were determined by computing the number of consecutive responses above the standard deviation during a control period. There was no significant relation between levels of ACTH, BE and the rate of fetal heart rate habituation. However, an index of HPA disregulation (uncoupling of ACTH and BE) was related significantly to fetal behavior. Fetal exposure to high levels of maternal BE relative to ACTH was associated with significantly lower rates of habituation. Results indicate that maternal stress and stress-related peptides influence fetal response patterns. It is possible that this influence persists over the life span.
                      Cover page: Maternal Hypothalamic-Pituitary-Adrenal Disregulation during the Third Trimester Influences Human Fetal ResponsesCreative Commons 'BY' version 4.0 license
                      Top