Stress and Childhood Asthma Risk: Overlapping Evidence from Animal Studies and Epidemiologic Research

<p/> <p>Rapidly expanding evidence increasingly strengthens the evidence linking psychological factors to asthma and allergy expression. Parallel studies in animals and humans demonstrating the influence of prenatal maternal stress and early caregiving experiences on the disrupted regulation of defensive biological systems [eg, sympathetic and adrenomedullary (SAM) system and the hypothalamicpituitary-adrenocortical (HPA) axis] provide strong proof of concept for this line of research. The consequent altered neuroimmune responses may influence the expression of immune-mediated disorders such as asthma as well as enhance an individual's susceptibility to other environmental factors that may also contribute to asthma risk.</p

Ecological Teacher Preparation: Rooting Place to Practice

This study is an exploration of ten faculty perceptions of the perceived influence of an ecological or place based focus in three teacher education programs. The qualities and characteristics of such programs, the influence that such a focus could have on curriculum, and the perceptions of faculty members regarding the interactions between the physical place in which the program resides and curriculum were of particular interest to this study. These questions are investigated by using an educational connoisseurship and criticism methodology. The qualities and characteristics of ecologically focused teacher education programs include immersion and integration, mentorship and reflection, and connection to “local knowledge” (Demarest, 2015). Faculty in the programs studied noted that their perceptions of their programs include an attention to place responsiveness, transfer, and affective domains. The implications of this study include how other teacher education programs can benefit from the utilization of this type of teacher education, the extension of the idea of ecological mindedness (McConnell Moroye & Ingman, 2017) from K-12 into teacher education and development, as well as addition of Place as another dimension of Eisner’s Ecology of Schooling (1976)

Understanding the temporal dynamics of a lowland river fish community at a hazardous intake and floodgate to inform safe operation

Entrainment and mortality of freshwater fish at hazardous pumping station intakes used for Flood Risk Management (FRM) are of global concern. Although upstream and downstream passage of diadromous fish has received considerable attention, the ecological behaviours of river-resident fish at these structures and how to protect these species from entrainment is poorly-understood. At a lowland flood-relief pumping station and floodgate situated off-channel (River Foss) to the main-river Yorkshire Ouse (York, England), multi-beam sonar (Dual-Frequency Identification Sonar: DIDSON) was used over a pluriannual (three years) period to investigate diel movements of river-resident fish in response to the variations in temperature, hydrology and pump and floodgate operation, and to determine fish-friendly management options. Diel lateral movements of thousands of river-resident fish between the main-river, floodgate operated channel (River Foss) and off-channel pump forebay were predominantly during the crepuscular period and daytime, proposing important considerations for when managers should operate pumps and associated flood infrastructure. Seasonal diel movements increased throughout winter during a baseline year (no pump operation) and overwintering behaviour was influenced by cooling river temperatures. A Generalized Linear Mixed Model (GLMM) revealed fish entered the off-channel forebay when river levels were stable and not when they were rising or falling, suggesting hydrological stability was important for the ecological function of this fish community. Two years of impact data (pumps operated) then revealed pump operations severely disrupted the ecological functions of local fish populations, which was also uniquely quantified over two independent 24h periods during which temporal fish counts were reduced by 85%. A trial period where the floodgate was lowered ahead of dawn significantly reduced fish immigration into the hazardous forebay when compared to two different hydrological periods. Modifying when the floodgate and pumps operate, including lowering the floodgate ahead of fish immigration at dawn, and starting pumps during the night (but not day), are therefore promising non-engineered management options to prevent immigration of fish into the hazardous off-channel pump forebay and to reduce entrainment and mortality risk during pump operation

Associations between Prenatal Exposure to Black Carbon and Memory Domains in Urban Children: Modification by Sex and Prenatal Stress

Background Whether fetal neurodevelopment is disrupted by traffic-related air pollution is uncertain. Animal studies suggest that chemical and non-chemical stressors interact to impact neurodevelopment, and that this association is further modified by sex. Objectives To examine associations between prenatal traffic-related black carbon exposure, prenatal stress, and sex with children’s memory and learning. Methods Analyses included N = 258 mother-child dyads enrolled in a Boston, Massachusetts pregnancy cohort. Black carbon exposure was estimated using a validated spatiotemporal land-use regression model. Prenatal stress was measured using the Crisis in Family Systems-Revised survey of negative life events. The Wide Range Assessment of Memory and Learning (WRAML2) was administered at age 6 years; outcomes included the General Memory Index and its component indices [Verbal, Visual, and Attention Concentration]. Relationships between black carbon and WRAML2 index scores were examined using multivariable-adjusted linear regression including effect modification by stress and sex. Results Mothers were primarily minorities (60% Hispanic, 26% Black); 67% had ≤12 years of education. The main effect for black carbon was not significant for any WRAML2 index; however, in stratified analyses, among boys with high exposure to prenatal stress, Attention Concentration Index scores were on average 9.5 points lower for those with high compared to low prenatal black carbon exposure (P3-way interaction = 0.04). Conclusion The associations between prenatal exposure to black carbon and stress with children’s memory scores were stronger in boys than in girls. Studies assessing complex interactions may more fully characterize health risks and, in particular, identify vulnerable subgroups

Interaction of Stress, Lead Burden, and Age on Cognition in Older Men: The VA Normative Aging Study

BACKGROUND. Low-level exposure to lead and to chronic stress may independently influence cognition. However, the modifying potential of psychosocial stress on the neurotoxicity of lead and their combined relationship to aging-associated decline have not been fully examined. OBJECTIVES. We examined the cross-sectional interaction between stress and lead exposure on Mini-Mental State Examination (MMSE) scores among 811 participants in the Normative Aging Study, a cohort of older U.S. men. METHODS. We used two self-reported measures of stress appraisal-a self-report of stress related to their most severe problem and the Perceived Stress Scale (PSS). Indices of lead exposure were blood lead and bone (tibia and patella) lead. RESULTS. Participants with higher self-reported stress had lower MMSE scores, which were adjusted for age, education, computer experience, English as a first language, smoking, and alcohol intake. In multivariable-adjusted tests for interaction, those with higher PSS scores had a 0.57-point lower (95% confidence interval, -0.90 to 0.24) MMSE score for a 2-fold increase in blood lead than did those with lower PSS scores. In addition, the combination of high PSS scores and high blood lead categories on one or both was associated with a 0.05-0.08 reduction on the MMSE for each year of age compared with those with low PSS score and blood lead level (p < 0.05). CONCLUSIONS. Psychological stress had an independent inverse association with cognition and also modified the relationship between lead exposure and cognitive performance among older men. Furthermore, high stress and lead together modified the association between age and cognition.National Institutes of Health (R01ES07821, R01HL080674, R01HL080674-02S1, R01ES013744, ES05257-06A1, P20MD000501, P42ES05947, ES03918-02); National Center for Research Resources General Clinical Research Center (M01RR02635); Leaves of Grass Foundation; United States Department of Veterans Affair

Associations between Traffic-Related Black Carbon Exposure and Attention in a Prospective Birth Cohort of Urban Children

Background: Ambient air pollution may have neurotoxic effects in children. Data examining associations between traffic-related air pollution and attention domains remain sparse. Objectives: We examined associations between black carbon (BC), a marker of traffic particles, and attention measures ascertained at 7–14 years of age among 174 children in a birth cohort based in the Boston, Massachusetts, area. Methods: We estimated BC levels using a validated spatial–temporal land-use regression model based on residence during children’s lifetime. Children completed the Conner’s Continuous Performance Test (CPT) measuring omission errors, commission errors, and hit reaction time (HRT), with higher scores indicating increased errors or slower reaction time. Multivariable-adjusted linear regression analyses were used to examine associations between BC and each attention outcome. Results: Children were primarily Hispanic (56%) and Caucasian (41%); 53% were boys. We found a positive association between higher BC levels with increased commission errors and slower HRT, adjusting for child IQ, age, sex, blood lead level, maternal education, pre- and postnatal tobacco smoke exposure, and community-level social stress. Notably, the association was weaker, though still positive, for the highest BC quartile relative to the middle two quartiles. Sex-stratified analysis demonstrated statistically significant associations between BC and both commission errors and HRT in boys, but BC was not significantly associated with any of the CPT outcomes in girls. Conclusions: In this population of urban children, we found associations between BC exposure and higher commission errors and slower reaction time. These associations were overall more apparent in boys than girls

Respiratory Sinus Arrhythmia as an Index of Vagal Activity during Stress in Infants: Respiratory Influences and Their Control

Respiratory sinus arrhythmia (RSA) is related to cardiac vagal outflow and the respiratory pattern. Prior infant studies have not systematically examined respiration rate and tidal volume influences on infant RSA or the extent to which infants' breathing is too fast to extract a valid RSA. We therefore monitored cardiac activity, respiration, and physical activity in 23 six-month old infants during a standardized laboratory stressor protocol. On average, 12.6% (range 0–58.2%) of analyzed breaths were too short for RSA extraction. Higher respiration rate was associated with lower RSA amplitude in most infants, and lower tidal volume was associated with lower RSA amplitude in some infants. RSA amplitude corrected for respiration rate and tidal volume influences showed theoretically expected strong reductions during stress, whereas performance of uncorrected RSA was less consistent. We conclude that stress-induced changes of peak-valley RSA and effects of variations in breathing patterns on RSA can be determined for a representative percentage of infant breaths. As expected, breathing substantially affects infant RSA and needs to be considered in studies of infant psychophysiology

Effects of Prenatal Social Stress and Maternal Dietary Fatty Acid Ratio on Infant Temperament: Does Race Matter?

Background: Infant temperament predicts a range of developmental and behavioral outcomes throughout childhood. Both maternal fatty acid intake and psychosocial stress exposures during pregnancy may influence infant temperament. Furthermore, maternal race may modify prenatal diet and stress effects. The goals of this study are to examine the joint effects of prenatal diet and stress and the modifying effects of race on infant behavior. Methods: Analyses included N=255 mother-infant dyads, primarily minorities (21% Blacks; 42% Hispanics), enrolled in an urban pregnancy cohort. Maternal prenatal stress was indexed by a negative life events (NLEs) score on the Crisis in Family Systems-Revised survey. Prenatal total daily intakes of polyunsaturated fatty acids (PUFAs) (n3, n6) were estimated from a food frequency questionnaire; n3:n6 ratios were calculated. Mothers completed the Infant Behavior Questionnaire-Revised (IBQ-R), a measure of infant temperament, when the children were 6 months old. Three commonly used dimensions were derived: Orienting & Regulation, Extraversion, and Negative Affectivity. Associations among prenatal stress, maternal n3:n6 ratio, and race/ethnicity on infant temperament, controlling for maternal education and age and child sex, were examined. Results: Among Blacks, prenatal stress effects on infant Orienting & Regulation scores were modified by maternal n3:n6 ratios (p=0.03): As NLEs increased, lower n3:n6 ratios predicted lower infant Orienting & Regulation scores, whereas higher n3:n6 ratios attenuated the effect of prenatal stress. There were no main or interaction effects predicting Extraversion or Negative Affectivity. Conclusions: An optimal PUFA ratio may protect the fetus from stress effects on infant behavior, particularly among Blacks. These findings may have implications for later neurodevelopment and social functioning predicted by early temperamental characteristics

Childhood Abuse and Age at Menarche

Purpose—Physical and sexual abuse are prevalent social hazards. We sought to examine the association between childhood physical and sexual abuse and age at menarche. Methods—Among 68,505 participants enrolled in the Nurses’ Health Study II we investigated the association between childhood physical abuse and sexual abuse on menarche prior to age 11 (early) or after age 15 (late) using multivariate logistic regression analysis, mutually adjusting for both types of abuse. Results—Fifty-seven percent of respondents reported some form of physical or sexual abuse in childhood. We found a positive dose-response association between severity of sexual abuse in childhood and risk for early menarche. Compared to women who reported no childhood sexual abuse, the adjusted odds ratio [AOR] for early menarche was 1.20 (95% confidence interval [CI], 1.10, 1.37) for sexual touching and 1.49 (95% CI, 1.34, 1.66) for forced sexual activity. Only severe physical abuse predicted early menarche (AOR=1.22, 95% CI, 1.10–1.37). Childhood physical abuse had a dose-response association with late age at menarche: AOR 1.17 (95% CI, 1.04, 1.32) for mild, 1.20 (95% CI, 1.08, 1.33) for moderate, and 1.50 (95% CI, 1.27, 1.77) for severe physical abuse. Sexual abuse was not associated with late menarche. Conclusion—Childhood abuse was very prevalent in this large cohort of U.S. women. Severity of childhood sexual abuse was associated with risk for early onset of menarche, and physical abuse was associated with both early and late onset menarche. Implications and Contribution—The severity of childhood sexual abuse and severe physical abuse were associated with risk for accelerated menarche, while severity of childhood physical was associated with risk for delayed onset of menarche. The nature of the association between different forms of childhood adversities and reproductive lifespan may vary

The influence of passive wedge-wire screen aperture and flow velocity on juvenile European eel exclusion, impingement and passage

The European eel (Anguilla anguilla) is a critically endangered catadromous fish. The decline has partly been attributed to water management infrastructure that abstract water from rivers for potable and industrial water supply, irrigation, hydroelectric power generation and flood defence; eels can be impinged on weedscreens and trashracks and entrained in pumps and turbines. The Eel Regulations (England and Wales) 2009 stipulates measures are required to provide safe (upstream and downstream) passage of eels past such hazardous intakes. Preventing impingement and entrainment of upstream migrating (glass eel and elver) and river-resident (yellow) juvenile eels at hazardous intakes may require fine-mesh aperture screens and low approach velocities due to eels' small size and relatively poor swimming capacity but quantitative evidence is lacking. Here, passive wedge-wire screen aperture (1, 2, 3 and 5 mm) and depth-averaged flow velocities (0, 0.1, 0.15 and 0.2 m∙s−1) both influenced the fate (i.e., impingement or passage) and behaviour (i.e., migratory separation or behavioural avoidance) of two size classes of juvenile eels (60–80 mm glass eels and 100–160 mm elvers) in an experimental flume. One and 2 mm aperture screens were required to physically exclude 60–80 mm and 100–160 mm. Up to 90% and 100% of the 60–80 mm and 100–160-mm size class eels were impinged at 0.2 m∙s−1 depth-averaged flow velocity, which also positively influence number of screen contacts per eel and time to eel fate (from first contact). A small proportion of 60–80 mm eels (9.2%) did not approach the screen due to migratory separation (i.e., positive rheotaxis) and eels narrower than the screen aperture did not always pass through the screen, and thus other biological or hydraulic processes may also influence screen passage. It is hoped that these findings help improve screening guidance for regulators, key stakeholders and water abstraction managers to further improve protective measures required for critically endangered eels