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Individuals with the short variant of the serotonin transporter linked polymorphic region gene are more susceptible than individuals homozygous for the long allele to the effects of stressful life events on risk for internalizing and externalizing problems. We tested whether individual differences in coping style explained this increased risk for problem behavior among youth who were at both genetic and environmental risk. Participants included 279 children, ages 8-11, from the Children's Experiences and Development Study. Caregivers and teachers reported on children's internalizing and externalizing symptoms, and caregivers and children on children's exposure to harsh parenting and parental warmth in middle childhood, and traumatic events. Children reported how frequently they used various coping strategies. Results revealed that short/short homozygotes had higher levels of internalizing problems compared with long allele carriers and that short allele carriers had higher levels of externalizing problems compared with long/long homozygotes under conditions of high cumulative risk. Moreover, among children who were homozygous for the short allele, those who had more cumulative risk indicators less frequently used distraction coping strategies, which partly explained why they had higher levels of internalizing problems. Coping strategies did not significantly mediate Gene × Environment effects on externalizing symptoms.

BackgroundGiven mixed findings as to whether stressful experiences and relationships are associated with increases or decreases in children's cortisol reactivity, we tested whether a child's developmental history of risk exposure explained variation in cortisol reactivity to an experimentally induced task. We also tested whether the relationship between cortisol reactivity and children's internalizing and externalizing problems varied as a function of their developmental history of stressful experiences and relationships.MethodParticipants included 400 children (M = 9.99 years, SD = 0.74 years) from the Children's Experiences and Development Study. Early risk exposure was measured by children's experiences of harsh, nonresponsive parenting at 3 years. Recent risk exposure was measured by children's exposure to traumatic events in the past year. Children's cortisol reactivity was measured in response to a social provocation task and parents and teachers described children's internalizing and externalizing problems.ResultsThe effect of recent exposure to traumatic events was partially dependent upon a child's early experiences of harsh, nonresponsive parenting: the more traumatic events children had recently experienced, the greater their cortisol reactivity if they had experienced lower (but not higher) levels of harsh, nonresponsive parenting at age 3. The lowest levels of cortisol reactivity were observed among children who had experienced the most traumatic events in the past year and higher (vs. lower) levels of harsh, nonresponsive parenting in early childhood. Among youth who experienced harsh, nonresponsive parent-child relationships in early childhood and later traumatic events, lower levels of cortisol reactivity were associated with higher levels of internalizing and externalizing problems.ConclusionsHypothalamic-pituitary-adrenal (HPA) axis reactivity to psychological stressors and the relationship between HPA axis reactivity and children's internalizing and externalizing problems vary as a function of a child's developmental history of exposure to stressful relationships and experiences.

Throughout this monograph, there has been frequent reference to levels of risk, inference of causation, testing for mediating variables, and the need to consider possible moderating influences. In this chapter, the authors review what is meant by these concepts, and then seek to pull together the findings from the English and Romanian Adoptee (ERA) studies that were relevant for these issues. (Contains 6 tables and 3 figures.)

It has come to be generally accepted that the psychopathological effects of psychosocial stress and adversity are diagnostically nonspecific. There is a good deal of supporting evidence in support of this assumption, even though it may be that the nonspecificity has been exaggerated through a failure to take account of comorbidity. This chapter presents findings on the designation of deprivation-specific psychological patterns (DSPs). These included an early onset (at least by age 6 years, the earliest age at which data were available for the whole sample) and persistence to 11 years of age. The persistence to 11-year requirement was introduced particularly because minor manifestations of DA were so frequent at age 6 years in the pooled comparison group. Without the persistence criterion, the association of DSPs with institutional deprivation would be much weakened. (Contains 5 tables and 8 figures.)

In chapter IV, the authors focused on their findings on the developmental course of deprivation-specific psychological patterns (DSPs). The authors rediscussed the syndrome concept in the light of two main considerations. First, the findings indicated substantial overlap among the four postulated DSPs at 15 years including CI and I/O before requiring cooccurrence with Q-A or DA. Second, they realized that, ordinarily, syndromes are defined on the basis of a unifying pathophysiology rather than a mere clustering together of symptoms. Although they have not identified the nature of such pathophysiology, the strong continuing association with institutional deprivation extending up to at least 6 months of age, plus the findings from the pilot brain imaging study points to the likelihood that there is a unifying pathophysiology. Accordingly, they conclude that, on balance, a coherent syndrome remains a strong possibility. (Contains 6 tables.)

Author(s): The Wellcome Trust Case Control Consortium; Management Committee; Paul R. Burton [1]; David G. Clayton [2]; Lon R. Cardon [3]; Nick Craddock [4]; Panos Deloukas [5]; Audrey Duncanson [6]; [...]

Author(s): Sergey Nejentsev [1, 57]; Joanna M. M. Howson (corresponding author) [1, 57]; Neil M. Walker [1]; Jeffrey Szeszko [1]; Sarah F. Field [1]; Helen E. Stevens [1]; Pamela Reynolds [...]

Cardiac sympathetic transmitter stores are reduced in the failing heart. In this study, we proposed to investigate whether the reduction of cardiac sympathetic neurotransmitters was associated with increased interstitial norepinephrine (NE) and reactive oxygen species in congestive heart failure (CHF), using a microdialysis technique and salicylate to detect .OH generation. Rabbits with and without rapid ventricular pacing (340 beats/min) were randomized to receive desipramine (10 mg/day) or placebo for 8 wk. Rapid pacing produced left ventricular dilation and systolic dysfunction. The failing myocardium also showed reduced tissue contents of NE and tyrosine hydroxylase protein and activity. In contrast, myocardial interstitial NE was increased in CHF (0.89 ± 0.11 ng/ml) compared with the sham-operated animals (0.26 ± 0.03 ng/ml). In addition, cardiac oxidative stress was increased in CHF animals as measured by myocardial interstitial .OH radical, tissue oxidized glutathione, and oxidized mitochondrial DNA. Desipramine treatment produced significant NE uptake inhibition as evidence by an exaggerated pressor response and a greater increase of myocardial interstitial NE in response to intravenous NE infusion but no significant effects on cardiac function or hemodynamics in sham-operated or CHF animals. However, desipramine treatment attenuated the reductions of tissue NE and tyrosine hydroxylase protein and activity in CHF. Desipramine also prevented the reduction of tyrosine hydroxylase produced by NE in PC12 cells. Thus the reduction of cardiac sympathetic neurotransmitters is related to the increased interstitial NE and tissue oxidative stress in CHF. Also, normal neuronal uptake of NE is required for NE or its oxidized metabolites to exert their neurotoxic effects. [ABSTRACT FROM AUTHOR]

In this paper, we develop a physiological oscillator model of which the output mimics the shape of the R-R interval Poincaré plot. To validate the model, simulations of various nervous conditions are compared with heart rate variability (HRV) data obtained from subjects under each prescribed condition. For a variety of sympathovagal balances, our model generates Poincaré plots that undergo alterations strongly resembling those of actual R-R intervals. By exploiting the oscillator basis of our model, we detail the way that low- and high-frequency modulation of the sinus node translates into R-R interval Poincaré plot shape by way of simulations and analytic results. With the use of our model, we establish that the length and width of a Poincaré plot are a weighted combination of low- and high-frequency power. This provides a theoretical link between frequency-domain spectral analysis techniques and time-domain Poincaré plot analysis. We ascertain the degree to which these principles apply to real R-R intervals by testing the mathematical relationships on a set of data and establish that the principles are clearly evident in actual HRV records. [ABSTRACT FROM AUTHOR]

Focuses on a study which determined whether changes in cardiac sympathetic nerve terminal function produced by norepinephrine infusion, associated with reduced nerve growth factor. Methodology of the study; Results and discussion.