Discrimination and perinatal depressive symptoms: The protective role of social support and resilience

BACKGROUND

Discrimination is an important social determinant of perinatal depression; however, evidence is limited regarding modifiable social and psychological factors that may moderate this association. We examined whether social support and resilience could protect against the adverse effects of discrimination on perinatal depressive symptoms.

METHODS

Pregnant people (N = 589) receiving Expect With Me group prenatal care in Nashville, TN and Detroit, MI completed surveys during third trimester of pregnancy and six months postpartum. Linear regression models tested the association between discrimination and depressive symptoms, and the moderating effects of social support and resilience, during pregnancy and postpartum.

RESULTS

The sample was predominantly Black (60.6 %), Hispanic (15.8 %) and publicly insured (71 %). In multivariable analyses, discrimination was positively associated with depressive symptoms during pregnancy (B = 4.44, SE = 0.37, p ≤0.001) and postpartum (B = 3.78, SE = 0.36, p < 0.001). Higher social support and resilience were associated with less depressive symptoms during pregnancy (B = -0.49, SE = 0.08, p < 0.001 and B = -0.67, SE = 0.10, p < 0.001, respectively) and postpartum (B = -0.32, SE = 0.07, p < 0.001 and B = -0.56, SE = 0.08, p < 0.001, respectively). Social support was protective against discrimination (pregnancy interaction B = -0.23, SE = 0.09, p = 0.011; postpartum interaction B = -0.35, SE = 0.07, p < 0.001). There was no interaction between discrimination and resilience at either time.

LIMITATIONS

The study relied on self-reported measures and only included pregnant people who received group prenatal care in two urban regions, limiting generalizability.

CONCLUSIONS

Social support and resilience may protect against perinatal depressive symptoms. Social support may also buffer the adverse effects of discrimination on perinatal depressive symptoms, particularly during the postpartum period.

The role of peripheral vision during decision-making in dynamic viewing sequences

Decision-making in team sports necessitates monitoring multiple performers located at different distances (i.e., viewing eccentricities) from a critical information source. The processing of peripheral information is generally impaired under anxiety and when responding to stimuli located at larger eccentricities. These hypotheses have not been sufficiently tested in dynamic performance environments. We examined how pressure and eccentricities affect decision-making and visual behaviour in 4v4 basketball defensive scenarios using a head mounted display. Experienced players monitored plays from the first-person perspective (centre position) and made defensive steps towards opponents threatening the basket from different eccentricities under low- and high-pressure. To tax working memory, participants simultaneously performed a backward counting task. Players responded slower and with lower accuracy to opponents at larger eccentricities. Players mostly fixated on the ball-carrier, but over 50% of fixations were located on peripheral players, indicating that information in the periphery must be frequently updated with foveal vision (i.e., pivot strategy). When pressured, participants increased mental effort and improved counting performance; however, gaze behaviour and decision-making were relatively unaffected. Findings suggest that basketball players respond more quickly to opponents positioned at lower compared to higher eccentricities at the cost of impaired responses to opponents in the periphery.

Dimensions of Early Adversity and Sexual Behavior in a US Population-Based Adolescent Sample

PURPOSE

Early life adversity (ELA) is associated with sexual risk, but ELA dimensions-and potential mechanisms-have been less examined. We evaluated associations between threat and deprivation-two key ELA dimensions-and sexual behaviors in adolescents. Secondary analyses investigated age at menarche as a mechanism linking ELA with sexual outcomes in girls. We predicted associations between threat and sexual behaviors, with younger age at menarche as a pathway.

METHODS

Data were from the National Comorbidity Survey, Adolescent Supplement. Adolescents and caregivers reported on youths' ELA experiences, which were categorized as threat- or deprivation-related. Adolescents reported if they engaged in sex (N = 9,937) and on specific sexual risk indicators, including age at first sex, number of past-year sexual partners, and condom use consistency ("always" vs. "not always" used). Girls reported age at menarche.

RESULTS

Threat (odds ratio [OR] = 1.76 [95% confidence interval [CI], 1.62-1.92]) and deprivation (OR = 1.51 [95% CI, 1.24-1.83]) were each linked with engagement in sex, ps<.05. Threat-related experiences were associated with multiple sexual risk markers, even when accounting for deprivation: earlier age at first sex (b = -0.20 [95% CI, -0.27 to 0.13]), greater number of partners (b = 0.17 [95% CI, 0.10-0.25]), and inconsistent condom use (OR = 0.72 [95% CI, 0.64-0.80]), ps <.001. Deprivation was not associated with sexual risk when adjusting for threat. We observed no significant indirect effects through age at menarche.

DISCUSSION

Although threat and deprivation were related to engagement in sexual activity, threat-related experiences were uniquely associated with sexual risk. Screening for threat-related ELA may identify adolescents at-risk for poor sexual health.

Total and dissolved phosphorus losses from agricultural headwater streams during extreme runoff events

Eutrophication continues to be a concerning global water quality issue. Managing and mitigating harmful algal blooms demands clear information on the conditions promoting large phosphorus losses from contributing watersheds. Of particular concern is the amount and form of phosphorus loading to receiving water bodies during extreme runoff events, which are expected to increase in frequency due to climate change. Five years (2015 to 2020) of water quantity and quality data from 11 agricultural watersheds in the lower Great Lakes basin were analyzed and used to model total and dissolved phosphorus losses. This study aimed to assess temporal dynamics in phosphorus concentrations and losses over runoff events covering a wide range of hydrologic conditions and to quantify their relative importance on annual phosphorus losses. Event concentration-discharge relationships for total and dissolved phosphorus were hysteretic and had contrasting dominant patterns across watersheds. The proportion of annual phosphorus losses during events was highly variable between watersheds, accounting for 47-94 %. Extreme events were particularly impactful: as few as three events per year were found to be responsible for nearly half of total phosphorus (20-50 %) and total dissolved phosphorus (14-44 %) losses. Variability in total and dissolved phosphorus losses and concentrations over a wide range of flow conditions suggests that event magnitude is an important control on the relative mobility of particulate and dissolved phosphorus fractions. This study showed that insights into nutrient dynamics and phosphorus budgets in the lower Great Lakes basin and agriculture dominated environments more broadly can be gained by assessing event nutrient losses with respect to flow conditions and patterns in concentration-discharge relationships.

Early Life Adversity and Clinical Intimate Partner Violence in Adulthood: The Mediating Role of Interpersonal Conflict in Adolescence

Intimate partner violence (IPV) is associated with adverse outcomes for both victims and perpetrators, though there is significant heterogeneity in manifestations of relationship violence. A growing amount of research has focused on elucidating predictors of clinical IPV-defined as severe violence involving institutional or medical intervention due to actual or potential injury-so as to better understand potential prevention and intervention targets. Early life adversity (ELA) is associated with IPV in adulthood, yet this literature focuses on discrete, retrospectively reported adversities (e.g., physical abuse and neglect) and has yet to consider clinical IPV as an outcome. Little is known about if and how broadly adverse early environments may confer risk for this specific form of relationship violence. We investigated associations between exposure to ELA prior to age five and clinical IPV victimization and perpetration by age 20 in a longitudinal, community-based sample of men and women in Australia (N = 588). Early life adversity was prospectively indexed by maternal reports of financial hardship, child chronic illness, maternal stressful life events, maternal depressive symptoms, parental discord, and parental separation. Youth interpersonal conflict life events at age 15-an interviewer-rated assessment of episodic stressors involving conflict across relationships in mid-adolescence-was tested as a potential mediator for both victims and perpetrators. Among women, ELA predicted IPV victimization and perpetration, and interpersonal conflict life events partially mediated the link between ELA and victimization, but not perpetration. Neither ELA nor interpersonal conflict life events predicted victimization or perpetration among men. Women exposed to ELA are at-risk for conflictual interpersonal relationships later in life, including violent intimate relationships, and deficits in conflict resolution skills may be one mechanism through which ELA leads to IPV victimization among this subgroup. Violence prevention and intervention efforts should target interpersonal skills, including conflict resolution, among women and girls exposed to adverse early environments.

Posttraumatic stress disorder and coping strategies in the postpartum period: A symptomics approach

Posttraumatic stress disorder (PTSD) has been increasingly recognized as a potential mental health concern for new mothers. Elevated PTSD symptoms have been associated with maladaptive coping strategies in the postpartum period, a time when women face many challenges, demands, and stressors. However, PTSD symptoms manifest in heterogeneous ways, and focusing only on total symptom scores may obscure more nuanced associations with particular coping styles. In a large, ethnically diverse sample of postpartum women from across the United States (N = 1,315), first we examined associations between total PTSD symptom severity with three distinct coping styles: active-emotional, avoidant-emotional, and problem-focused. In models adjusting for race and educational attainment, total PTSD symptom severity was significantly positively associated with tendencies to use active- and avoidant-emotional, but not problem-focused, coping. We then adopted a novel "symptomics" approach, employing relative importance analyses to examine associations between individual PTSD symptoms with the coping styles. These analyses identified PTSD symptoms that were most strongly associated with each coping style. Notably, whereas several symptoms explained variance in avoidant-emotional coping, only a few symptoms contributed most to active-emotional and problem-focused coping. Moreover, non-specific symptoms of PTSD that are shared with other psychopathology (e.g., difficulty concentrating, loss of interest) explained significant proportions of variance across all coping styles. Collectively, results suggest that a symptomics approach may provide more nuanced insight into how PTSD symptoms are linked to various coping styles in postpartum women, which can help inform potential screening and intervention targets for at-risk women during this period.

Novel predictors related to hysteresis and baseflow improve predictions of watershed nutrient loads: An example from Ontario's lower Great Lakes basin

Eutrophication has re-emerged in the lower Great Lakes basin resulting in critical water quality issues. Models that accurately predict nutrient loading from streams are needed to inform appropriate nutrient management decisions. Generalized additive models (GAMs) that use surrogate data from sensors to predict nutrient loads offer an alternative to commonly applied linear regression and may better handle relationship non-linearities and skewed water quality data. Five years (2015-2020) of water quantity and quality data from 11 agricultural watersheds in southern Ontario were used to develop GAMs to predict total phosphorus (TP) and nitrate (NO₃^-) loads. This study aimed to 1) use GAMs to predict nutrient loads using both common and novel predictors and 2) quantify and examine the variability in seasonal and annual nutrient loads. Along with routine surrogate model predictors (i.e., flow, turbidity, and seasonality), the addition of the baseflow proportion and the hydrograph position of flow observations improved model performance. Conversely, including the antecedent precipitation index minimally affected model performance, regardless of constituent. Seasonal and annual patterns in TP and NO₃^- load predictions mirrored that of the hydrologic regime. This study showed that parsimonious GAMs featuring novel model predictors can be used to predict nutrient loads while accounting for the partitioning of surface and subsurface flow paths and hysteresis between streamflow and water quality parameters that are frequently observed in a wide range of environments.

Elucidating posttraumatic stress symptom dimensions and health correlates among postpartum women

BACKGROUND

Posttraumatic stress disorder (PTSD) is associated with interpersonal dysfunction and adverse maternal health during the perinatal period (extending from conception through one year postpartum). However, PTSD is a heterogeneous disorder, and little is known about which aspects of this disorder may be particularly deleterious to the health of new mothers. Such data may inform more personalized approaches to PTSD prevention and treatment among postpartum women.

METHODS

Using confirmatory factor analysis, we compared three models of PTSD symptom structure-the four-factor dysphoria model, four-factor emotional numbing model, and five-factor dysphoric arousal model-in 1,663 postpartum women from the Community and Child Health Network (CCHN). We examined associations between PTSD symptom dimensions of the best-fitting model with four correlates relevant to maternal health and functioning-parenting stress, partner relationship stress, relationship satisfaction, and contraceptive use.

RESULTS

Though all models fit well, the five-factor dysphoric arousal model provided optimal fit. Symptom dimensions from this model-re-experiencing, avoidance, numbing, dysphoric arousal, and anxious arousal-evidenced differential associations with the maternal health indicators. Numbing symptoms were most strongly associated with indicators of poor interpersonal functioning, whereas dysphoric arousal symptoms were most strongly related to low-efficacy contraceptive use.

LIMITATIONS

Our cross-sectional study assessed DSM-IV PTSD symptoms.

CONCLUSIONS

PTSD symptoms among postpartum women are best-represented by five factors. Numbing symptoms (e.g., restricted affect, detachment) are most strongly associated with interpersonal difficulties, whereas dysphoric arousal symptoms (e.g., agitation, irritability) are linked with low-efficacy contraceptive use. Screening for these symptoms may help promote the health of new mothers.

Key dimensions of post-traumatic stress disorder and endothelial dysfunction: a protocol for a mechanism-focused cohort study

INTRODUCTION

Both trauma exposure and post-traumatic stress disorder (PTSD) are associated with increased risk of cardiovascular disease (CVD), the leading cause of death in the USA. Endothelial dysfunction, a modifiable, early marker of CVD risk, may represent a physiological mechanism underlying this association. This mechanism-focused cohort study aims to investigate the relationship between PTSD (both in terms of diagnosis and underlying symptom dimensions) and endothelial dysfunction in a diverse, community-based sample of adult men and women.

METHODS AND ANALYSIS

Using a cohort design, 160 trauma-exposed participants without a history of CVD are designated to the PTSD group (n=80) or trauma-exposed matched control group (n=80) after a baseline diagnostic interview assessment. Participants in the PTSD group have a current (past month) diagnosis of PTSD, whereas those in the control group have a history of trauma but no current or past psychiatric diagnoses. Endothelial dysfunction is assessed via flow-mediated vasodilation of the brachial artery and circulating levels of endothelial cell-derived microparticles. Two higher order symptom dimensions of PTSD-fear and dysphoria-are measured objectively with a fear conditioning paradigm and attention allocation task, respectively. Autonomic imbalance, inflammation, and oxidative stress are additionally assessed and will be examined as potential pathway variables linking PTSD and its dimensions with endothelial dysfunction. Participants are invited to return for a 2-year follow-up visit to reassess PTSD and its dimensions and endothelial dysfunction in order to investigate longitudinal associations.

ETHICS AND DISSEMINATION

This study is conducted in compliance with the Helsinki Declaration and University of California, Los Angeles Institutional Review Board. The results of this study will be disseminated via articles in peer-reviewed journals and presentations at academic conferences and to community partners.

TRIAL REGISTRATION NUMBER

NCT03778307; pre-results.

Racial and ethnic disparities in posttraumatic psychopathology among postpartum women

People of color in the United States disproportionately bear the burden of trauma and posttraumatic stress disorder (PTSD). Pregnant women of color are at particular risk, as perinatal PTSD is associated with adverse maternal and child health. However, PTSD is a heterogeneous disorder comprising discrete symptom dimensions. Adopting a dimensional understanding of PTSD could aid in identifying women at-risk for the consequences of posttraumatic psychopathology and guide treatment selection. In a large sample of Latina, Black, and non-Hispanic White postpartum women in the United States (N = 1663), we examined racial and ethnic differences in the factors of the dysphoric arousal model-a leading dimensional model of PTSD. This model is characterized by five symptom dimensions: re-experiencing, avoidance, numbing, dysphoric arousal, and anxious arousal. Past-year trauma in this sample was common, afflicting nearly 70% of women. In unadjusted models, women of color exhibited more severe PTSD symptom levels across dimensions except for dysphoric arousal, with Black mothers particularly affected. In models adjusted for age, education, and poverty, Black women continued to report elevated symptoms of avoidance and, relative to Latina mothers, re-experiencing symptoms. In contrast, White women reported more dysphoric arousal symptoms relative to women of color. Illuminating differential patterns of symptom dimensions across racial and ethnic groups is critical to PTSD assessment and treatment and may shed light on disparities. Perinatal healthcare may be an important opportunity for posttraumatic symptom screening, and greater understanding of racial and ethnic variation in posttraumatic symptom dimensions can guide targeted intervention selection for perinatal women.

Associations between Adverse Childhood Experiences and Sexual Risk among Postpartum Women

Epidemiological evidence suggests that exposure to adverse childhood experiences (ACEs) is associated with sexual risk, especially during adolescence, and with maternal and child health outcomes for women of reproductive age. However, no work has examined how ACE exposure relates to sexual risk for women during the postpartum period. In a convenience sample of 460 postpartum women, we used linear and logistic regression to investigate associations between ACE exposure (measured using the Adverse Childhood Experiences Scale) and five sexual risk outcomes of importance to maternal health: contraceptive use, efficacy of contraceptive method elected, condom use, rapid repeat pregnancy, and incidence of sexually transmitted infections (STIs). On average, women in the sample were 25.55 years of age (standard deviation = 5.56); most identified as Black (60.4%), White (18%), or Latina (14.8%). Approximately 40% were exposed to adversity prior to age 18, with the modal number of experiences among those exposed as 1. Women exposed to ACEs were significantly less likely to use contraception; more likely to elect less-efficacious contraceptive methods; and used condoms less frequently (p = 0.041 to 0.008). ACE exposure was not associated with rapid repeat pregnancy or STI acquisition, p > 0.10. Screening for ACEs during pregnancy may be informative to target interventions to reduce risky sexual behavior during the postpartum period.

Estimating cumulative wastewater treatment plant discharge influences on acesulfame and Escherichia coli in a highly impacted watershed with a fully-integrated modelling approach

Wastewater treatment plant (WWTP) discharge is often considered a principal source of surface water contamination. In this study, a three-dimensional fully-integrated groundwater-surface water model was used to simulate the transport characteristics and cumulative loading of an artificial sweetener (acesulfame) and fecal indicator bacteria (Escherichia coli) from WWTPs within a 6800 km² mixed-use, highly impacted watershed in Ontario, Canada. The model, which employed 3.5 × 10⁶ computational nodes and 15 layers, facilitated a comprehensive assessment of groundwater-surface water interactions under high and low flow conditions; processes typically not accounted for in WWTP cumulative effects models. Simulations demonstrate that the model had significant capacity in reproducing the average and transient multi-year groundwater and surface water flow conditions in the watershed. As a proxy human-specific conservative tracer, acesulfame was useful for model validation and to help inform the representation of watershed-scale transport processes. Using a uniform WWTP acesulfame loading rate of 7.14 mg person^-1 day^-1, the general spatial trends and magnitudes of the acesulfame concentration profile along the main river reach within the watershed were reproduced; however, model performance was improved by tuning individual WWTP loading rates. Although instream dilution and groundwater-surface water interactions were strongly dependent on flow conditions, the main reach primarily consisted of groundwater discharge zones. For this reason, hydrodynamic dispersion in the hyporheic zone is shown as the predominant mechanism driving acesulfame into near-stream shallow groundwater, while under high flow conditions, the simulations demonstrate the potential for advective flushing of the shallow groundwater. Regarding the cumulative impact of the WWTPs on E. coli concentrations in the surface flow system, simulated transient E. coli levels downstream of WWTPs in the watershed were significantly lower than observed values, thus highlighting the potential importance of other sources of E. coli in the watershed.

Associations between intimate partner violence profiles and mental health among low-income, urban pregnant adolescents

Background

Intimate partner violence (IPV) during pregnancy is associated with adverse maternal and child health outcomes, including poor mental health. Previous IPV research has largely focused on women’s victimization experiences; however, evidence suggests young women may be more likely to engage in bilateral violence (report both victimization and perpetration) or perpetrate IPV (unilateral perpetration) during pregnancy than to report being victimized (unilateral victimization). This study examined prevalence of unilateral victimization, unilateral perpetration, and bilateral violence, and the association between these IPV profiles and mental health outcomes during pregnancy among young, low-income adolescents.

Methods

Survey data were collected from 930 adolescents (14–21 years; 95.4% Black and Latina) from fourteen Community Health Centers and hospitals in New York City during second and third trimester of pregnancy. Multivariable regression models tested the association between IPV profiles and prenatal depression, anxiety, and distress, adjusting for known predictors of psychological morbidity.

Results

Thirty-eight percent of adolescents experienced IPV during their third trimester of pregnancy. Of these, 13% were solely victims, 35% were solely perpetrators, and 52% were engaged in bilateral violence. All women with violent IPV profiles had significantly higher odds of having depression and anxiety compared to individuals reporting no IPV. Adolescents experiencing bilateral violence had nearly 4-fold higher odds of depression (OR = 3.52, 95% CI: 2.43, 5.09) and a nearly 5-fold increased likelihood of anxiety (OR = 4.98, 95% CI: 3.29, 7.55). Unilateral victims and unilateral perpetrators were also at risk for adverse mental health outcomes, with risk of depression and anxiety two- to three-fold higher, compared to pregnant adolescents who report no IPV. Prenatal distress was higher among adolescents who experienced bilateral violence (OR = 2.84, 95% CI: 1.94, 4.16) and those who were unilateral victims (OR = 2.21, 95% CI: 1.19, 4.12).

Conclusions

All violent IPV profiles were associated with adverse mental health outcomes among pregnant adolescents, with bilateral violence having the most detrimental associations. Comprehensive IPV screening for both victimization and perpetration experiences during pregnancy is warranted. Clinical and community prevention efforts should target pregnant adolescents and their partners to reduce their vulnerability to violence and its adverse consequences.

Trial registration

ClinicalTrials.gov, NCT00628771. Registered 29 February 2008.

Adolescent chronic variable social stress influences exploratory behavior and nicotine responses in male, but not female, BALB/cJ mice

Anxiety disorders and nicotine use are significant contributors to global morbidity and mortality as independent and comorbid diseases. Early-life stress, potentially via stress-induced hypothalamic-pituitary-adrenal axis (HPA) dysregulation, can exacerbate both. However, little is known about the factors that predispose individuals to the development of both anxiety disorders and nicotine use. Here, we examined the relationship between anxiety-like behaviors and nicotine responses following adolescent stress. Adolescent male and female BALB/cJ mice were exposed to either chronic variable social stress (CVSS) or control conditions. CVSS consisted of repeated cycles of social isolation and social reorganization. In adulthood, anxiety-like behavior and social avoidance were measured using the elevated plus-maze (EPM) and social approach-avoidance test, respectively. Nicotine responses were assessed with acute effects on body temperature, corticosterone production, locomotor activity, and voluntary oral nicotine consumption. Adolescent stress had sex-dependent effects on nicotine responses and exploratory behavior, but did not affect anxiety-like behavior or social avoidance in males or females. Adult CVSS males exhibited less exploratory behavior, as indicated by reduced exploratory locomotion in the EPM and social approach-avoidance test, compared to controls. Adolescent stress did not affect nicotine-induced hypothermia in either sex, but CVSS males exhibited augmented nicotine-induced locomotion during late adolescence and voluntarily consumed less nicotine during adulthood. Stress effects on male nicotine-induced locomotion were associated with individual differences in exploratory locomotion in the EPM and social approach-avoidance test. Relative to controls, adult CVSS males and females also exhibited reduced corticosterone levels at baseline and adult male CVSS mice exhibited increased corticosterone levels following an acute nicotine injection. Results suggest that the altered nicotine responses observed in CVSS males may be associated with HPA dysregulation. Taken together, adolescent social stress influences later-life nicotine responses and exploratory behavior. However, there is little evidence of an association between nicotine responses and prototypical anxiety-like behavior or social avoidance in BALB/cJ mice.

Association Between Maternal Comorbidities and Emergency Department Use Among a National Sample of Commercially Insured Pregnant Women

OBJECTIVES

Evidence suggests that, despite routine engagement with the health system, pregnant women commonly seek emergency care. The objectives of this study were to examine the association between maternal comorbidities and emergency department (ED) use among a national sample of commercially insured pregnant women.

METHODS

We conducted a retrospective cohort study using multipayer medical claims data maintained by the Health Care Cost Institute for women ages 18 to 44 years with a live singleton birth in 2011 (N = 157,786). The association between common maternal comorbidities (e.g., hypertension, gestational diabetes) and ED use during pregnancy was examined using multilevel models, while controlling for age, region, and residential zip code.

RESULTS

Twenty percent (n = 31,413) of pregnant women had one or more ED visit (mean ± SD = 1.52 ± 1.15). Among those who used the ED, 29% had two or more visits, and 11% had three or more visits. Emergency care seekers were significantly more likely to have one or more comorbid condition compared to those with no emergency care: 30% versus 21%, respectively (p < 0.001). Pregnant women with asthma had 2.5 times the likelihood of having had any ED visit (adjusted odds ratio [AOR] = 2.46, 95% confidence interval [CI] = 2.32-2.62). There was a significant increase in the probability (approximately 50%) of ED use among pregnant women with diabetes (AOR = 1.47, 95% CI = 1.33-1.63) or hypertension (AOR = 1.49, 95% CI = 1.43-1.55) or who were obese (AOR = 1.55, 95% CI = 1.47-1.64). Increased odds associated with gestational diabetes were more modest, resulting in a 13% increased odds of using the ED (AOR = 1.13, 95% CI = 1.07-1.18). Less than 0.6% of pregnant women (n = 177) received emergency care that resulted in a hospital admission. The admission rate was 0.4% (189 admissions/47,608 ED visits).

CONCLUSIONS

Among pregnant women, comorbidity burden was associated with more ED utilization. Efforts to reduce acute unscheduled care and improve care coordination during pregnancy should target interventions to patient comorbidity.

Expect With Me: development and evaluation design for an innovative model of group prenatal care to improve perinatal outcomes

BACKGROUND

Despite biomedical advances and intervention efforts, rates of preterm birth and other adverse outcomes in the United States have remained relatively intransigent. Evidence suggests that group prenatal care can reduce these risks, with implications for maternal and child health as well as substantial cost savings. However, widespread dissemination presents challenges, in part because training and health systems have not been designed to deliver care in a group setting. This manuscript describes the design and evaluation of Expect With Me, an innovative model of group prenatal care with a strong integrated information technology (IT) platform designed to be scalable nationally.

METHODS/DESIGN

Expect With Me follows clinical guidelines from the American Congress of Obstetricians and Gynecologists. Expect With Me incorporates the best evidence-based features of existing models of group care with a novel integrated IT platform designed to improve patient engagement and support, enhance health behaviors and decision making, connect providers and patients, and improve health service delivery. A multisite prospective longitudinal cohort study is being conducted to examine the impact of Expect With Me on perinatal and postpartum outcomes, and to identify and address barriers to national scalability. Process and outcome evaluation will include quantitative and qualitative data collection at patient, provider, and organizational levels. Mixed-method data collection includes patient surveys, medical record reviews, patient focus groups; provider surveys, session evaluations, provider focus groups and in-depth interviews; an online tracking system; and clinical site visits. A two-to-one matched cohort of women receiving individual care from each site will provide a comparison group (n = 1,000 Expect With Me patients; n = 2,000 individual care patients) for outcome and cost analyses.

DISCUSSION

By bundling prevention and care services into a high-touch, high-tech group prenatal care model, Expect With Me has the potential to result in fundamental changes to the health care system to meet the "triple aim:" better healthcare quality, improved outcomes, and lower costs. Findings from this study will be used to optimize the dissemination and effectiveness of this model.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02169024 . Retrospectively registered on June 18, 2014.

Towards a more accurate quantitative assessment of seasonal Cryptosporidium infection risks in surface waters using species and genotype information

Many Cryptosporidium species/genotypes are not considered infectious to humans, and more realistic estimations of seasonal infection risks could be made using human infectious species/genotype information to inform quantitative microbial risk assessments (QMRA). Cryptosporidium oocyst concentration and species/genotype data were collected from three surface water surveillance programs in two river basins [South Nation River, SN (2004-09) and Grand River, GR (2005-13)] in Ontario, Canada to evaluate seasonal infection risks. Main river stems, tributaries, agricultural drainage streams, water treatment plant intakes, and waste water treatment plant effluent impacted sites were sampled. The QMRA employed two sets of exposure data to compute risk: one assuming all observed oocysts were infectious to humans, and the other based on the fraction of oocysts that were C. hominis and/or C. parvum (dominant human infectious forms of the parasite). Viability was not considered and relative infection risk was evaluated using a single hypothetical recreational exposure. Many sample site groupings for both river systems, had significant seasonality in Cryptosporidium occurrence and concentrations (p ≤ 0.05); occurrence and concentrations were generally highest in autumn for SN, and autumn and summer for GR. Mean risk values (probability of infection per exposure) for all sites combined, for each river system, were roughly an order of magnitude lower (avg. of SN and GR 5.3 × 10^-5) when considering just C. parvum and C. hominis oocysts, in relation to mean infection risk (per exposure) assuming all oocysts were infectious to humans (5.5 × 10^-4). Seasonality in mean risk (targeted human infectious oocysts only) was most strongly evident in SN (e.g., 7.9 × 10^-6 in spring and 8.1 × 10^-5 in summer). Such differences are important if QMRA is used to quantify effects of water safety/quality management practices where inputs from a vast array of fecal pollution sources can readily occur. Cryptosporidium seasonality in water appears to match the seasonality of human infections from Cryptosporidium in the study regions. This study highlights the importance of Cryptosporidium species/genotype data to help determine surface water pollution sources and seasonality, as well as to help more accurately quantify human infection risks by the parasite.

Predictors of Adherence to Nicotine Replacement Therapy (Nicotine Patch) Among Homeless Persons Enrolled in a Randomized Controlled Trial Targeting Smoking Cessation

INTRODUCTION

Adherence to smoking cessation treatment is generally low, especially among socio-economically disadvantaged groups including individuals experiencing homelessness and those with mental illnesses. Despite the high smoking rates in homeless populations (~70%) no study to date has systematically examined predictors of adherence to nicotine replacement therapy (NRT) in this population.

OBJECTIVE

The aim of this secondary analysis was to identify predictors of adherence to NRT in a smoking cessation trial conducted among homeless smokers.

METHODS

Secondary analysis of data from a randomized controlled trial enrolling 430 persons who were homeless and current cigarette smokers. Participants were assigned to one of the two study conditions to enhance smoking cessation: Motivational Interviewing (MI; 6 sessions of MI + 8 weeks of NRT) or Standard Care (Brief advice to quit+ 8 weeks of NRT). The primary outcome for the current analysis was adherence to NRT at end of treatment (8 weeks following randomization). Adherence was defined as a total score of zero on a modified Morisky adherence scale). Demographic and baseline psychosocial, tobacco-related, and substance abuse measures were compared between those who did and did not adhere to NRT.

RESULTS

After adjusting for confounders, smokers who were depressed at baseline (OR=0.58, 95% CI, 0.38-0.87, p=0.01), had lower confidence to quit (OR=1.10, 95% CI, 1.01-1.19, p=0.04), were less motivated to adhere (OR=1.04, 95% CI, 1.00-1.07, p=0.04), and were less likely to be adherent to NRT. Further, age of initial smoking was positively associated with adherence status (OR= 0.83, 95% CI, 0.69-0.99, p=0.04).

CONCLUSION

These results suggest that smoking cessation programs conducted in this population may target increased adherence to NRT by addressing both depression and motivation to quit.

TRIAL REGISTRATION

clinicaltrials.gov: NCT00786149.

Abstinence rates among college cigarette smokers enrolled in a randomized clinical trial evaluating Quit and Win contests: The impact of concurrent hookah use

OBJECTIVE

To examine baseline characteristics and biochemically verified 1-, 4-, and 6-month tobacco quit rates among college students enrolled in a Quit and Win cessation trial, comparing those who concurrently smoke both hookah and cigarettes with those who deny hookah use.

METHODS

Analyses were conducted on data from 1217 college students enrolled in a Quit and Win tobacco cessation randomized clinical trial from 2010-2012. Multivariable logistic regression (MLR) analyses examined group differences in baseline characteristics and cotinine verified 30-day abstinence at 1, 4, and 6-month follow-up, adjusting for baseline covariates.

RESULTS

Participants smoked 11.5(±8.1) cigarettes per day on 28.5(±3.8) days/month, and 22% smoked hookah in the past 30days. Hookah smokers (n=270) were more likely to be male (p<0.0001), younger (p<0.0001), report more binge drinking (p<0.0001) and score higher on impulsivity (p<0.001). MLR results indicate that hookah users, when compared to non-users, had a 36% decrease in odds of self-reported 30-day abstinence at 4-months (OR=0.64, 95% CI=0.45-0.93, p=0.02) and a 63% decrease in odds in biochemically verified continuous abstinence at 6-months (OR=0.37, CI=0.14-0.99, p=0.05).

CONCLUSION

College cigarette smokers who concurrently use hookah display several health risk factors and demonstrate lower short and long-term tobacco abstinence rates.

The distribution of Salmonella enterica serovars and subtypes in surface water from five agricultural regions across Canada

Serovar prevalence of the zoonotic pathogen, Salmonella enterica, was compared among 1624 surface water samples collected previously from five different Canadian agricultural watersheds over multiple years. Phagetyping, pulsed field gel electrophoresis (PFGE), and antimicrobial resistance subtyping assays were performed on serovars Enteritidis, Typhimurium, and Heidelberg. Serovars and subtypes from surface water were compared with those from animal feces, human sewage, and serovars reported to cause salmonellosis in Canadians. Sixty-five different serovars were identified in surface water; only 32% of these were isolated from multiple watersheds. Eleven of the 13 serovars most commonly reported to cause salmonellosis in Canadians were identified in surface water; isolates of these serovars constituted >40% of the total isolates. Common phagetypes and PFGE subtypes of serovars associated with illness in humans such as S. Enteritidis and S. Typhimurium were also isolated from surface water and animal feces. Antimicrobial resistance was generally low, but was highest among S. Typhimurium. Monitoring of these rivers helps to identify vulnerable areas of a watershed and, despite a relatively low prevalence of S. enterica overall, serovars observed in surface water are an indication of the levels of specific S. enterica serovars present in humans and animals.

Aldehyde dehydrogenase-1a1 induces oncogene suppressor genes in B cell populations

The deregulation of B cell differentiation has been shown to contribute to autoimmune disorders, hematological cancers, and aging. We provide evidence that the retinoic acid-producing enzyme aldehyde dehydrogenase 1a1 (Aldh1a1) is an oncogene suppressor in specific splenic IgG1(+)/CD19(-) and IgG1(+)/CD19(+) B cell populations. Aldh1a1 regulated transcription factors during B cell differentiation in a sequential manner: 1) retinoic acid receptor alpha (Rara) in IgG1(+)/CD19(-) and 2) zinc finger protein Zfp423 and peroxisome proliferator-activated receptor gamma (Pparg) in IgG1(+)/CD19(+) splenocytes. In Aldh1a1(-/-) mice, splenic IgG1(+)/CD19(-) and IgG1(+)/CD19(+) B cells acquired expression of proto-oncogenic genes c-Fos, c-Jun, and Hoxa10 that resulted in splenomegaly. Human multiple myeloma B cell lines also lack Aldh1a1 expression; however, ectopic Aldh1a1 expression rescued Rara and Znf423 expressions in these cells. Our data highlight a mechanism by which an enzyme involved in vitamin A metabolism can improve B cell resistance to oncogenesis.

Using Campylobacter spp. and Escherichia coli data and Bayesian microbial risk assessment to examine public health risks in agricultural watersheds under tile drainage management

Human campylobacteriosis is the leading bacterial gastrointestinal illness in Canada; environmental transmission has been implicated in addition to transmission via consumption of contaminated food. Information about Campylobacter spp. occurrence at the watershed scale will enhance our understanding of the associated public health risks and the efficacy of source water protection strategies. The overriding purpose of this study is to provide a quantitative framework to assess and compare the relative public health significance of watershed microbial water quality associated with agricultural BMPs. A microbial monitoring program was expanded from fecal indicator analyses and Campylobacter spp. presence/absence tests to the development of a novel, 11-tube most probable number (MPN) method that targeted Campylobacter jejuni, Campylobacter coli, and Campylobacter lari. These three types of data were used to make inferences about theoretical risks in a watershed in which controlled tile drainage is widely practiced, an adjacent watershed with conventional (uncontrolled) tile drainage, and reference sites elsewhere in the same river basin. E. coli concentrations (MPN and plate count) in the controlled tile drainage watershed were statistically higher (2008-11), relative to the uncontrolled tile drainage watershed, but yearly variation was high as well. Escherichia coli loading for years 2008-11 combined were statistically higher in the controlled watershed, relative to the uncontrolled tile drainage watershed, but Campylobacter spp. loads for 2010-11 were generally higher for the uncontrolled tile drainage watershed (but not statistically significant). Using MPN data and a Bayesian modelling approach, higher mean Campylobacter spp. concentrations were found in the controlled tile drainage watershed relative to the uncontrolled tile drainage watershed (2010, 2011). A second-order quantitative microbial risk assessment (QMRA) was used, in a relative way, to identify differences in mean Campylobacter spp. infection risks among monitoring sites for a hypothetical exposure scenario. Greater relative mean risks were obtained for sites in the controlled tile drainage watershed than in the uncontrolled tile drainage watershed in each year of monitoring with pair-wise posterior probabilities exceeding 0.699, and the lowest relative mean risks were found at a downstream drinking water intake reference site. The second-order modelling approach was used to partition sources of uncertainty, which revealed that an adequate representation of the temporal variation in Campylobacter spp. concentrations for risk assessment was achieved with as few as 10 MPN data per site. This study demonstrates for the first time how QMRA can be implemented to evaluate, in a relative sense, the public health implications of controlled tile drainage on watershed-scale water quality.

Salmonella serotype diversity and seasonality in urban and rural streams

AIMS

To investigate the prevalence, seasonality and genetic diversity of Salmonella enterica serotypes, particularly those of human and veterinary health significance, in urban and rural streams.

METHODS AND RESULTS

Using a swab collection technique and multiple culture media for isolation, Salmonella were detected in 78.4% of water samples (November 2003 to July 2005) taken from urban and rural/agricultural streams in the Grand River watershed (Ontario, Canada). Among 235 isolates, there were 38 serotypes, with the predominant serotypes and phagetypes (PT) being Salmonella Typhimurium PT 104 and Salmonella Heidelberg PT 19. These are also the most common Salmonella serotypes found in humans and farm animals locally and across Canada, a trend not commonly reported. The urban stream had more frequent Salmonella occurrence, greater serotype diversity and greater genetic variability (based on pulsed field gel electrophoresis) of specific strains compared with the rural/agricultural streams. Distinct seasonality in serotypes of health significance was observed only in the rural/agricultural streams, which is likely a reflection of seasonal source inputs in these watersheds. Despite the lower occurrence of these strains in stream water in the colder months, laboratory studies did not support reduced survival of Salm. Typhimurium and Salm. Heidelberg at lower temperatures, although survival differences were observed with other serotypes.

CONCLUSIONS

A diverse range of Salmonella serotypes and PT were obtained from both urban and rural/agricultural streams, with the predominant strains being those most frequently associated with human and veterinary disease in Canada.

SIGNIFICANCE AND IMPACT OF THE STUDY

The ubiquitous nature of Salmonella in water and the predominance of serotypes/PT of human or veterinary health significance suggest that the aquatic environment is a reservoir for this bacterium and could be involved in the transport and dissemination of this pathogen between hosts.

Smoking patterns, attitudes and motives: unique characteristics among 2-year versus 4-year college students

Given the previously documented higher rates of smoking among 2-year college students in comparison with 4-year university students, this study compares smoking patterns, attitudes and motives among 2-year and 4-year college students. Two thousand two hundred and sixty-five undergraduate students aged 18-25 years at a 2-year college and a 4-year university completed an online survey in 2008. Current (past 30-day) smoking was reported by 43.5% of 2-year and 31.9% of 4-year college students, and daily smoking was reported by 19.9% of 2-year and 8.3% of 4-year college students. Attending a 2-year college was associated with higher rates of current smoking [odds ratio (OR) = 1.72] and daily smoking (OR = 2.84), and with less negative attitudes regarding smoking, controlling for age, gender, ethnicity and parental education. Also, compared with 4-year college student smokers, 2-year college smokers had lower motivation to smoke for social reasons, but more motivation to smoke for affect regulation, after controlling for age, gender, ethnicity and parental education. Two- and 4-year college students report different smoking patterns, attitudes and motives. These distinctions might inform tobacco control messages and interventions targeting these groups of young adults.

Perceived Treatment Assignment and Smoking Cessation in a Clinical Trial of Bupropion

Research on tobacco cessation pharmacotherapy often relies on double-blind, placebo-controlled randomized trials. These studies are designed to control for the placebo effect (i.e., the influence of participants' expectations on treatment outcome). Psychoactive effects of smoking cessation medications such as bupropion may allow participants to correctly guess their treatment assignment at rates greater than chance. Perceived treatment assignment could potentially impact smoking cessation rates. The aim of this study was to determine the impact of perceived treatment assignment on end-of-treatment cotinine-verified smoking abstinence among African-American light smokers [≤10 cigarettes per day (cpd)] enrolled in a double-blind, placebo-controlled study of bupropion. Participants were randomized to bupropion (150 mg bid) or placebo and received identical written materials and health education counseling. Participants (n = 390) included in this study reported their perceived treatment assignment on the end-of-treatment (week 7) survey. They were predominantly female (63.1%), 48.1 years (SD = 11.2), and smoked 8 cpd (SD = 2.5). The majority (81.3%) smoked menthol cigarettes. Participants given bupropion were more likely to correctly guess their treatment assignment (69%; 140/203) than those assigned to placebo (51.3%; 96/187). Quit rates by treatment assignment were 31.5% (bupropion) versus 13.9% (placebo) (OR = 2.78, 95% CI 1.61–5.43, P &lt; 0.01). After adjusting for treatment, participants who perceived assignment to bupropion versus placebo were not more likely to be abstinent (OR = 1.37; 95% CI 0.71–2.64, P = 0.35).The interaction between treatment and perceived treatment assignment was also nonsignificant. Consistent with two previous studies with bupropion, there was evidence of blinding failure for the treatment group. However, in our study, perceived treatment assignment did not significantly impact cotinine-verified cessation outcome at end-of-treatment (week 7). These findings suggest that the role of perceived treatment assignment on smoking cessation with bupropion may differ for light smokers compared to heavier smokers (&gt;10 cpd) sampled in the two earlier studies. Current findings might indicate that expectations of pharmacotherapy are less salient for light smokers.

Nomegestrol acetate may enhance the skeletal effects of estradiol on biochemical markers of bone turnover in menopausal women after a 12-week treatment period

OBJECTIVE

To compare the effects of a 12-week treatment with 17ss-estradiol given alone and in sequential combination with 3.75 mg of nomegestrol acetate (Naemis), or a placebo on biochemical markers of bone turnover in menopausal women.

PATIENTS AND METHODS

A double-blind, randomized, placebo and estradiol-controlled multicenter study was conducted. A total of 176 patients who had been menopausal for 1-10 years, hysterectomized or not, having no contraindications to hormone replacement therapy, without any risks factors for osteoporosis, received one of these treatments during 12 weeks: placebo, 1.5 mg estradiol (E(2)) or 1.5 mg E(2)/3.75 mg nomegestrol acetate (E(2)/NOMAC). The primary efficacy variables were the change in bone markers (total alkaline phosphatase, bone alkaline phosphatase and osteocalcin; urinary type-I collagen peptides).

RESULTS

The four biochemical markers decreased only in the E(2)/NOMAC group. Bone alkaline phosphatase, osteocalcin and urinary type-I collagen peptides decreased in the E(2) group. For both active treatment groups compared to the placebo group, the changes were statistically significant after a 12-week treatment. There were no statistically significant differences between the E(2) and the E(2)/NOMAC groups except for total serum alkaline phosphatase, whose mean value decreased in the E(2)/NOMAC group but increased slightly in the E(2) group (p < 0.001). Furthermore, after a 6-week treatment, the changes in biochemical markers of bone turnover were similar to those found after 12 weeks. Safety data were satisfactory with regard to estradiol given alone or in combination with nomegestrol acetate.

CONCLUSION

These results demonstrated that 1.5 mg E(2) is effective in reducing bone turnover in postmenopausal women and proved that the combination of 1.5 mg E(2) and 3.75 mg nomegestrol acetate has no deleterious effect on bone remodelling.

The clinical variability of maternally inherited diabetes and deafness is associated with the degree of heteroplasmy in blood leukocytes

CONTEXT

Maternally inherited diabetes and deafness (MIDD) is a rare form of diabetes with a matrilineal transmission, sensorineural hearing loss, and macular pattern dystrophy due to an A to G transition at position 3243 of mitochondrial DNA (mtDNA) (m.3243A>G). The phenotypic heterogeneity of MIDD may be the consequence of different levels of mutated mtDNA among mitochondria in a given tissue.

OBJECTIVE

The aim of the present study was thus to ascertain the correlation between the severity of the phenotype in patients with MIDD and the level of heteroplasmy in the blood leukocytes.

PARTICIPANTS

The GEDIAM prospective multicenter register was initiated in 1995. Eighty-nine Europid patients from this register, with MIDD and the mtDNA 3243A>G mutation, were included. Patients with MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) or with mitochondrial diabetes related to other mutations or to deletions of mtDNA were excluded.

RESULTS

A significant negative correlation was found between levels of heteroplasmy and age of the patients at the time of sampling for molecular analysis, age at the diagnosis of diabetes, and body mass index. After adjustment for age at sampling for molecular study and gender, the correlation between heteroplasmy levels and age at the diagnosis of diabetes was no more significant. The two other correlations remained significant. A significant positive correlation between levels of heteroplasmy and HbA(1c) was also found and remained significant after adjustment for age at molecular sampling and gender.

CONCLUSIONS

These results support the hypothesis that heteroplasmy levels are at least one of the determinants of the severity of the phenotype in MIDD.

Serine 124 completes the Tyr, Lys and Ser triad responsible for the catalysis of human type 1 3beta-hydroxysteroid dehydrogenase

Human 3beta-hydroxysteroid dehydrogenase/isomerase (3beta-HSD) is a key steroidogenic enzyme that catalyzes the first step in the conversion of circulating dehydroepiandrosterone (DHEA), pregnenolone or 17alpha-hydroxypregenolone to produce the appropriate, active steroid hormone(s): estradiol, testosterone, progesterone, aldosterone or cortisol respectively. Our mutagenesis studies have identified Tyr154 and Lys158 as catalytic residues for the 3beta-HSD reaction. Our three-dimensional homology model of 3beta-HSD shows that Tyr154 and Lys158 are oriented near the 3beta-hydroxyl group of the bound substrate steroid, and predicts that Ser123 or Ser124 completes a Tyr-Lys-Ser catalytic triad that operates in many other dehydrogenases. The S123A and S124A mutants of human type 1 3beta-hydroxysteroid dehydrogenase/isomerase (3beta-HSD1) were created by PCR-based mutagenesis, expressed in insect cells using baculovirus and purified to homogeneity. The S124A mutant exhibits no 3beta-HSD activity and has a K(m) value (83.6 microM) for the isomerase substrate that is threefold greater than that of wild-type 1 isomerase. In contrast, S123A has substantial 3beta-HSD activity (DHEA K(m)=11.2 microM; k(cat)=0.8 min(-1)) and utilizes isomerase substrate, 5-androstene-3,17-dione, with a K(m) value (27.6 microM) that is almost identical to wild-type. The K(m) value (4.3 microM) of S124A for NADH as an allosteric activator of isomerase is similar to that of the wild-type 1 enzyme, indicating that Ser124 is not involved in cofactor binding. S123A utilizes NAD as a cofactor for 3beta-HSD and NADH as the activator for isomerase with K(m) values that are similar to wild-type. The 3beta-HSD activities of S123A and wild-type 3beta-HSD increase by 2.7-fold when the pH is raised from 7.4 to the optimal pH 9.7, but S124A exhibits very low residual 3beta-HSD activity that is pH-independent. These kinetic analyses strongly suggest that the Ser124 residue completes the catalytic triad for the 3beta-HSD activity. Since there are 29 Ser residues in the primary structure of human 3beta-HSD1, our homology model of the catalytic domain has been validated by this accurate prediction. A role for Ser124 in the binding of the isomerase substrate, which is the 3beta-HSD product-steroid of the bifunctional enzyme protein, is also suggested. These observations further characterize the structure/function relationships of human 3beta-HSD and bring us closer to the goal of selectively inhibiting the type 1 enzyme in placenta to control the timing of labor or in hormone-sensitive breast tumors to slow their growth.

Detection of microlesions induced by heavy ions using liposomes filled with fluorescent dye

In cells irradiation by heavy ions has been hypothesized to produce microlesions, regions of local damage. In cell membranes this damage is thought to manifest itself in the form of holes. The primary evidence for microlesions comes from morphological studies of cell membranes, but this evidence is still controversial, especially since holes also have been observed in membranes of normal, nonirradiated, cells. However, it is possible that damage not associated with histologically discernable disruptions may still occur. In order to resolve this issue, we developed a system for detecting microlesions based on liposomes filled with fluorescent dye. We hypothesized that if microlesions form in these liposomes as the result of irradiation, then the entrapped dye will leak out into the surrounding medium in a measurable way. Polypropylene vials containing suspensions of vesicles composed of either dipalmitoyl phosphatidylcholine, or a combination of egg phosphatidylcholine and cholesterol were irradiated at the Brookhaven National Laboratory using 56Fe ions at 1 GeV/amu. In several cases we obtained a significant loss of the entrapped dye above the background level. Our results suggest that holes may form in liposomes as the result of heavy ion irradiation, and that these holes are large enough to allow leakage of cell internal contents that are at least as large as a 1 nm diameter calcein molecule.

Effects of a progestogen on normal human breast epithelial cell apoptosis in vitro and in vivo

Many investigators have reported cyclic proliferation of normal human breast epithelial cells. A delicate balance between proliferation and apoptosis (programmed cell death) ensures breast homeostasis. Both the follicular and luteal phases of the menstrual cycle are characterized by proliferation, whereas apoptosis occurs only at the end of the latter phase. In this study, we observed that the withdrawal of a synthetic progestin (nomegestrol acetate or NOMAC), but not continuous treatment with it, induced apoptosis of normal human breast epithelial cells in vitro and in women who applied NOMAC gel to their breasts. Furthermore, this apoptotic response was specific to normal breast cells, since withdrawal of NOMAC did not induce apoptosis of tumoral T47D cells in vitro or of fibroadenoma cells in women. These observations open up new perspectives in the prevention of hyperplasia and breast cancer.

Experimental demonstration of noninvasive transskull adaptive focusing based on prior computed tomography scans

Developing minimally invasive brain surgery by high-intensity focused ultrasound beams is of great interest in cancer therapy. However, the skull induces strong aberrations both in phase and amplitude, resulting in a severe degradation of the beam shape. Thus, an efficient brain tumor therapy would require an adaptive focusing, taking into account the effects of the skull. In this paper, we will show that the acoustic properties of the skull can be deduced from high resolution CT scans and used to achieve a noninvasive adaptive focusing. Simulations have been performed with a full 3-D finite differences code, taking into account all the heterogeneities inside the skull. The set of signals to be emitted in order to focus through the skull can thus be computed. The complete adaptive focusing procedure based on prior CT scans has been experimentally validated. This could have promising applications in brain tumor hyperthermia but also in transcranial ultrasonic imaging.

3xP3-EGFP marker facilitates screening for transgenic silkworm Bombyx mori L. from the embryonic stage onwards

Transgenesis was recently achieved in Bombyx mori L., but it has proved difficult and time-consuming to screen the numerous progeny to identify the transgenic individuals. As the 3xP3-EGFP marker has been shown to be a suitable universal marker for transgenic insects (Nature 402 (1999) 370), we evaluated its use for embryonic-stage screening for B. mori L. germline transformation. Using the piggyBac-derived vector pBac[3xP3-EGFPaf], we were able to isolate four transgenic individuals from about 120,000 embryos (560 broods). The screening was straightforward due to EGFP production in the G1 embryonic stemmata, which was visible through the translucent egg chorion. EGFP was produced in the stemmata and central and peripheral nervous systems from the fifth day of embryonic development. It persisted at high levels in the stemmata throughout the larval stage, and was also present in the compound eyes and nervous tissues of the pupae and the compound eyes of the moths.

The early steps of oligodendrogenesis: insights from the study of the plp lineage in the brain of chicks and rodents

Oligodendrocytes are the myelin-forming cells of the central nervous system. Over the last decade, their development in the embryonic brain and spinal cord has been documented following the discovery of early oligodendroglial markers. These early expressed oligodendroglial genes nevertheless show differences in their spatiotemporal pattern of expression and it is not yet clear if their expression is linked in a linear way. This review highlights the common themes underlying the spatiotemporal aspects of oligodendrogenesis in chick and rodent brain and discusses some recent advances in the knowledge of the cell lineage expressing plp, one of the early oligodendroglial genes. We suggest a model of oligodendroglial commitment whereby definitive oligodendroglial progenitor formation is preceded by a primitive neuroglial progenitor stage and whereby different oligodendrocyte lineages might segregate from either plp-positive or plp-negative primitive progenitor cells.

The utility of the CES-D as a depression screening measure among low-income women attending primary care clinics. The Center for Epidemiologic Studies-Depression

OBJECTIVE

Depressive disorders are among the most common medical disorders seen in primary care practice. The Center for Epidemiologic Studies-Depression (CES-D) scale is one of the measures commonly suggested for detecting depression in these clinics. However, to our knowledge, there have been no previous studies examining the validity of the CES-D among low-income women attending primary care clinics.

METHOD

Low-income women attending public primary care clinics (n = 179, ages 20-77) completed the CES-D and the Diagnostic Interview Schedule for the DSM-IV (DIS-IV).

RESULTS

The results supported the validity of the CES-D. The standard cut-score of 16 and above yielded a sensitivity of .95 and specificity of .70 in predicting Major Depressive Disorder (MDD). However, over two-thirds of those who screened positive did not meet criteria for MDD (positive predictive value = .28). The standard cut-score appears valid, but inefficient for depression screening in this population. An elevated cut-score of 34 yielded a higher specificity (.95) and over 50 percent of the patients who screened positive had a MDD (positive predictive value = .53), but at great cost to sensitivity (.45).

CONCLUSION

Results indicated that the CES-D appears to be as valid for low-income, minority women as for any other demographic group examined in the literature. Despite similar validity, the CES-D appears to be inadequate for routine screening in this population. The positive predictive value remains very low no matter which cut-scores are used. The costs of the false positive rates could be prohibitive, especially in similar public primary care settings.

Sonic hedgehog-dependent emergence of oligodendrocytes in the telencephalon: evidence for a source of oligodendrocytes in the olfactory bulb that is independent of PDGFRα signaling

Most studies on the origin of oligodendrocyte lineage have been performed in the spinal cord. By contrast, molecular mechanisms that regulate the appearance of the oligodendroglial lineage in the brain have not yet attracted much attention. We provide evidence for three distinct sources of oligodendrocytes in the mouse telencephalon. In addition to two subpallial ventricular foci, the anterior entopeduncular area and the medial ganglionic eminence, the rostral telencephalon also gives rise to oligodendrocytes. We show that oligodendrocytes in the olfactory bulb are generated within the rostral pallium from ventricular progenitors characterized by the expression of Plp. We provide evidence that these Plp oligodendrocyte progenitors do not depend on signal transduction mediated by platelet-derived growth factor receptors (PDGFRs), and therefore propose that they belong to a different lineage than the PDGFRα-expressing progenitors. Moreover, induction of oligodendrocytes in the telencephalon is dependent on sonic hedgehog signaling, as in the spinal cord. In all these telencephalic ventricular territories, oligodendrocyte progenitors were detected at about the same developmental stage as in the spinal cord. However, both in vivo and in vitro, the differentiation into O4-positive pre-oligodendrocytes was postponed by 4-5 days in the telencephalon in comparison with the spinal cord. This delay between determination and differentiation appears to be intrinsic to telencephalic oligodendrocytes, as it was not shortened by diffusible or cell-cell contact factors present in the spinal cord.

In vivo and in vitro effects of prochloraz and nonylphenol ethoxylates on trout spermatogenesis

We investigated the effects of in vivo exposure to non-lethal concentrations of two chemicals commonly discharged into the aquatic environment, prochloraz and nonylphenol diethoxylate (NP2EO - Igepal(R) 210), on the development of spermatogenesis in trout. The in vitro effects on basal and insulin-like growth factor-1 (IGF-I) stimulated DNA synthesis by early germ cells were also studied. In vivo, rainbow trout were exposed for 2 or 3 weeks to waterborne prochloraz (21 and 175 nmol/l) and/or NP2EO (68-970 nmol/l) renewed continuously, or periodically. Only the highest concentrations of NP2EO (225-970 nmol/l) induced a significant increase in blood plasma vitellogenin in juvenile or maturing male trout. When prepubertal fish were exposed for 15 days to prochloraz, the spermatogenetic process was significantly inhibited as shown by the stage of gonadal development reached 3 weeks after exposure. This effect was, to a great extent, reversible within 9 weeks post-exposure. When fish in the initial stage of spermatogenesis were exposed for 21-27 days to 580 nmol/l NP2EO, a 20-40% reduction of the gonadosomatic index was observed 4.5 weeks post-exposure, and the spermatogenetic process was partly inhibited. In vitro, testicular cells obtained at different stages of spermatogenesis were cultured for 4.5 days in the presence or not of the tested molecules and with IGF-I or not. 3H-thymidine (3H-Tdr) incorporation was measured according to Loir (Mol. Reprod. Dev. 53 (1999) 424) and 125I-IGF-I specific binding was determined according to Le Gac et al. (Mol. Reprod. Dev. 44 (1996) 35). Irrespective of the spermatogenetic stage, basal 3H-Tdr incorporation was decreased by prochloraz concentrations > or =10 micromol/l. The presence of IGF-I (10-100 ng/ml) stimulated 3H-Tdr incorporation; this response to IGF-I began to decrease at 25-50 micromol/l prochloraz. In parallel, a dose-dependent increase of IGF-I specific binding was induced by prochloraz 1-100 micromol/l. Similarly, basal and IGF-I-stimulated 3H-Tdr incorporation was decreased by nonylphenol polyethoxylate (NpnEO; starting at 10 micromol/l), NP2EO and NP (30 micromol/l); a dose-dependent increase of IGF-I specific binding was also induced by NP and NPnEO. While 1-100 nmol/l 17beta-estradiol had no effect in our in vitro system, Triton(R) X-100 acted as NPnEO on 3H-Tdr incorporation. Beside their known endocrine disrupting effects on sex steroid production or action, these lipophilic molecules could act on germ cells by disrupting cell membrane receptivity to peptide hormones like growth factors.

The engineered, cytosolic form of human type I 3beta-hydroxysteroid dehydrogenase/isomerase: purification, characterization and crystallization

Human type I 3beta-hydroxysteroid dehydrogenase/isomerase (3beta-HSD/isomerase) is an integral membrane protein of human placental trophoblast and of insect Sf9 cells transfected with recombinant baculovirus containing the cDNA encoding the enzyme. Purified native or wild-type enzyme remains in solution only in the presence of detergent that may prevent crystallization. The membrane-spanning domain (residues 283-310) of the enzyme protein was deleted in the cDNA using PCR-based mutagenesis. The modified enzyme was expressed by baculovirus in the cytosol instead of in the microsomes and mitochondria of the Sf9 cells. The cytosolic form of 3beta-HSD/isomerase was purified using affinity chromatography with Cibacron Blue 1000. The NAD(+) and NaCl used to elute the enzyme were removed by size-exclusion centrifugation. Hydroxylapatite chromatography yielded a 26-fold purification of the enzyme. SDS-PAGE revealed a single protein band for the purified cytosolic enzyme (monomeric molecular mass 38.8 kDa) that migrated just below the wild-type enzyme (monomeric molecular mass 42.0 kDa). Michaelis-Menten constants measured for 3beta-HSD substrate (dehydroepiandrosterone) utilization by the purified cytosolic enzyme (K(m)=4.5 microM, V(max)=53 nmol/min per mg) and the pure wild-type enzyme (K(m)=3.7 microM, V(max)=43 nmol/min per mg), for isomerase substrate (5-androstene-3,17-dione) conversion by the purified cytosolic (K(m)=25 microM, V(max)=576 nmol/min per mg) and wild-type (K(m)=28 microM, V(max)=598 nmol/min per mg) enzymes, and for NAD(+) reduction by the 3beta-HSD activities of the cytosolic (K(m)=35 microM, V(max)=51 nmol/min per mg) and wild-type (K(m)=34 microM, V(max)=46 nmol/min per mg) enzymes are nearly identical. The isomerase activity of the cytosolic enzyme requires allosteric activation by NADH (K(m)=4.6 microM, V(max)=538 nmol/min per mg) just like the wild-type enzyme (K(m)=4.6 microM, V(max)=536 nmol/min per mg). Crystals of the purified, cytosolic enzyme protein have been obtained. The inability to crystallize the detergent-solubilized, wild-type microsomal enzyme has been overcome by engineering a cytosolic form of this protein. Determining the tertiary structure of 3beta-HSD/isomerase will clarify the mechanistic roles of potentially critical amino acids (His(261), Tyr(253)) that have been identified in the primary structure.

Human medulloblastoma cell line DEV is a potent tool to screen for factors influencing differentiation of neural stem cells

The aim of our study was to investigate whether a human neural cell line could be used as a reliable screening tool to examine the functional conservation, in humans, of transcription factors involved in neuronal or glial specification in other species. Gain-of-function experiments were performed on DEV cells, a cell line derived from a human medulloblastoma. Genes encoding nine different transcription factors were tested for their influence on the process of specification of human DEV cells towards a neuronal or glial fate. In a first series of experiments, DEV cells were transfected with murine genes encoding transcription factors known to be involved in the neuronal differentiation cascade. Neurogenins-1, -2, and -3; Mash-1; and NeuroD increased the differentiation of DEV cells towards a neuronal phenotype by a factor of 2-3.5. In a second series of experiments, we tested transcription factors involved in invertebrate glial specification. In the embryonic Drosophila CNS, the development of most glial cells depends on the master regulatory gene glial cell missing (gcm). Expression of gcm in DEV cells induced a twofold increase of astrocytic and a sixfold increase of oligodendroglial cell types. Interestingly, expression of tramtrack69, which is required in all Drosophila glial cells, resulted in a fourfold increase of only the oligodendrocyte phenotype. Expression of the related tramtrack88 protein, which is not expressed in the fly glia, or the C. elegans lin26 protein showed no effect. These results show that the Drosophila transcription factor genes tested can conserve their function upon transfection into the human DEV cells, qualifying this cell line as a screening tool to analyze the mechanisms of neuronal and glial specification.

Optimal focusing by spatio-temporal inverse filter. II. Experiments. Application to focusing through absorbing and reverberating media

To focus ultrasonic waves in an unknown heterogeneous medium using a phased array, one has to calculate the optimal set of signals to be applied on the transducers of the array. (In most applications of ultrasound, medical imaging, medical therapy, nondestructive testing, the first step consists of focusing a broadband ultrasound beam deeply inside the medium to be investigated.) Focusing in a homogeneous medium simply requires to compensate for the varying focus-array elements geometrical distances. Nevertheless, heterogeneities in the medium, in terms of speed of sound, density, or absorption, may strongly degrade the focusing. Different techniques have been developed in order to correct such aberrations induced by heterogeneous media (time reversal, speckle brightness, for example). In the companion to this paper, a new broadband focusing technique was investigated: the spatio-temporal inverse filter. Experimental results obtained in various media, such as reverberating and absorbing media, are presented here. In particular, intraplate echoes suppression and high-quality focusing through a human skull, as well as hyper-resolution in a reverberating medium, will be shown. It is important to notice that all these experiments were performed with fully programmable multichannel electronics whose use is required to fully exploit the spatio-temporal technique.

Breaking of time reversal invariance in nonlinear acoustics

Time-reversal invariance of nonlinear acoustic wave propagation is experimentally investigated. Reversibility is studied for propagation shorter or longer than shock formation distance. In the first case, time-reversal invariance holds and a sinusoid distorted by nonlinearities during forward propagation progressively recovers its initial shape after the time-reversal operation. In the second case, reversibility is broken locally at the shock front as a time-reversal operation transforms a stable compression shock into an unstable expansion shock. Achieving experimentally the time-reversal process with a time-reversal mirror made of reversible piezoelectric transducers for very broadband signals, would require transducers with huge bandwidths. To date, such transducers remain unavailable. In order to overcome this technical limitation, we restricted ourselves in this study to one-dimensional (1D) propagation, for which an experimental ersatz of a time-reversal mirror can be used. Indeed, in a 1D case, the time-reversal operation applied on a plane wave can be mimicked for an antisymmetric wave form by a reflection of the plane wave onto a pressure-release interface.

Optimal focusing by spatio-temporal inverse filter. I. Basic principles

A focusing technique based on the inversion of the propagation operator relating an array of transducers to a set of control points inside a medium was proposed in previous work [Tanter et al., J. Acoust. Soc. Am. 108, 223-234 (2000)] and is extended here to the time domain. As the inversion of the propagation operator is achieved both in space and time, this technique allows calculation of the set of temporal signals to be emitted by each element of the array in order to optimally focus on a chosen control point. This broadband inversion process takes advantage of the singular-value decomposition of the propagation operator in the Fourier domain. The physical meaning of this decomposition is explained in a homogeneous medium. In particular, a definition of the number of degrees of freedom necessary to define the acoustic field generated by an array of limited aperture in a focal plane of limited extent is given. This number corresponds to the number of independent signals that can be created in the focal area both in space and time. In this paper, this broadband inverse-focusing technique is compared in homogeneous media with the classical focusing achieved by simple geometrical considerations but also with time-reversal focusing. It is shown that, even in a simple medium, slight differences appear between these three focusing strategies. In the companion paper [Aubry et al., J. Acoust. Soc. Am. 110, 48-58 (2001)] the three focusing techniques are compared in heterogeneous, absorbing, or complex media where classical focusing is strongly degraded. The strong improvement achieved by the spatio-temporal inverse-filter technique emphasizes the great potential of multiple-channel systems having the ability to apply completely different signal waveforms on each transducer of the array. The application of this focusing technique could be of great interest in various ultrasonic fields such as medical imaging, nondestructive testing, and underwater acoustics.

Monofocal origin of telencephalic oligodendrocytes in the anterior entopeduncular area of the chick embryo

Oligodendrocytes are the myelin-forming cells in the central nervous system. In the brain, oligodendrocyte precursors arise in multiple restricted foci, distributed along the caudorostral axis of the ventricular neuroepithelium. In chick embryonic hind-, mid- and caudal forebrain, oligodendrocytes have a basoventral origin, while in the rostral fore-brain oligodendrocytes emerge from alar territories (Perez Villegas, E. M., Olivier, C., Spassky, N., Poncet, C., Cochard, P., Zalc, B., Thomas, J. L. and Martinez, S. (1999) Dev. Biol. 216, 98–113). To investigate the respective territories colonized by oligodendrocyte progenitor cells that originate from either the basoventral or alar foci, we have created a series of quail-chick chimeras. Homotopic chimeras demonstrate clearly that, during embryonic development, oligodendrocyte progenitors that emerge from the alar anterior entopeduncular area migrate tangentially to invade the entire telencephalon, whereas those from the basal rhombomeric foci show a restricted rostrocaudal distribution and colonize only their rhombomere of origin. Heterotopic chimeras indicate that differences in the migratory properties of oligodendroglial cells do not depend on their basoventral or alar ventricular origin. Irrespective of their origin (basal or alar), oligodendrocytes migrate only short distances in the hindbrain and long distances in the prosencephalon. Furthermore, we provide evidence that, in the developing chick brain, all telencephalic oligodendrocytes originate from the anterior entopeduncular area and that the prominent role of anterior entopeduncular area in telencephalic oligodendrogenesis is conserved between birds and mammals.

Modeling of early events in T cell signal transduction after controlled T cell activation by peptide major histocompatibility complex

Calcium signaling was observed in murine T cells over time, starting at a precise moment of contact with a layer of fibroblasts expressing a stimulatory major histocompatibility class II-peptide complex. The contact was controlled by a film-thinning apparatus. Intracellular calcium levels were followed with the ratiometric dye, Fura-2. The calcium response was highly synchronized and well fitted by a mathematical model. The model includes three components: a sequence of reactions occurring after T cell receptor (TCR) triggering; InsP3-mediated calcium release from intracellular stores (Meyer and Stryer, Proc. Natl. Acad. Sci. USA 85: 5051-5055, 1988); and slow changes in levels phospholipase C-gammal (PLCgammal) reflecting a decrease in receptor triggering rate. Each component in the model controls a different part of the response-the initial delay, the sharp rise, and the slow decay, respectively. Kinetic parameters determined from curve fitting were the initial delay in calcium signaling defined as the time when [PLCgammal] reached its half of its maximum (76 s), the coefficient characterizing calcium efflux from endoplasmic reticulum (ER) (2.86 microM s(-1), expressed per liter of cell volume), and a rate constant characterizing the diminishing yield of production of PLCgammal (0.00046 s(-1)) by active TCR. Only the parameter representing PLCgammal production varied much from cell to cell.

Controlling duration of contact between T cells and antigen-presenting cells

A new method which allows precise control of the duration of contact between T cells and antigen-presenting cells (APCs) has been developed. A glass coverslip coated with poly-L-lysine, and then with T cells, was placed at the base of a cylindrical well, and the well was filled with liquid medium. A round coverslip, on which APCs were adhered, was supported on the surface of the medium by surface tension, cell-side down. By withdrawing medium from four capillary holes near the base of the well, the coverslip could be lowered to initiate contact between T cells and APCs at a defined time zero. The contact was broken at desired time points by re-introducing medium into the well in order to separate the two coverslips. Each cell type remained adherent to its original surface after separation for all contact times studied. The T cells were monitored for intracellular calcium mobilization using the fluorescent dye, Fura-2. Contact durations of less than 1 min did not trigger calcium signals. Contact durations of 3 and 5 min induced strong calcium signals. Breaking the contact caused a rapid decrease in intracellular calcium levels. This method of cell manipulation allows precise control of the duration of contact of T cells with APCs, while keeping the cells under continuous observation. The measurements so obtained provide a quantitative understanding of the dynamics of early T cell activation.

Grandparents as parents: research findings and policy recommendations

This article presents an overview of research on grandparenthood in the latter decades of the twentieth century. Theories contributing to understanding of the grandparenting role are discussed, and significant factors affecting the grandparenting experience--including sex, age, retirement status, race, and ethnicity--are reviewed. The special case of grandparents raising grandchildren is explored through a review of demographics, outcomes for children in grandparent foster care, and the impact of raising grandchildren on grandparents. Interventions supporting custodial grandparents and the grandchildren in their care are examined. Drawing on the findings and implications of this overview, recommendations for policy, clinical practice, professional education, and future research are offered.