Black Adolescent Self-Perceptions: The Roles of Ethnic Identity and Stress Exposure.

Ethnic identity is associated with various positive outcomes for Black adolescents, but more information is needed about its potential to protect adolescents exposed to stress. Stressful life events predict a range of health outcomes, yet few studies have examined their association with adolescent self-perception. Ethnic identity may serve as protection from stress. This study examines longitudinal data to understand relationships between ethnic identity, stressful life events, and self-perception (i.e., social competence, behavioral conduct, and global self-worth). The sample included 140 adolescents (65% female; 93% Black) with an average age of 12.55 (SD = 0.85). Results indicate stressful life events are associated with behavioral conduct self-perception, and ethnic identity is associated with global self-worth. Ethnic identity behavior and other group orientation are associated with self-perception. Ethnic identity and ethnic identity behavior moderate the relationship between stressful life events and behavioral conduct self-perception. Understanding the connections between adolescent stressors and strengths provides insight into research, practice, and policy directions to promote positive outcomes.

New Insights into the Phototoxicity of Anthracene-Based Chromophores: The Chloride Salt Effect†.

Unraveling the causes underlying polycyclic aromatic hydrocarbon phototoxicity is an essential step in understanding the harmful effects of these compounds in nature. Toward this end, we have studied the DNA interactions and photochemistry of N1-(anthracen-9-ylmethyl)ethane-1,2-diaminium dichloride in the presence and absence of NaF, KF, NaCl, KCl, NaBr, KBr, NaI, and KI (350 nm hν, pH 7.0). Exposing pUC19 plasmid to UV light in solutions containing 400 mM KCl formed significantly more direct strand breaks in DNA compared to no-salt control reactions. In contrast, NaCl increased DNA damage moderately, while the sodium(I) and potassium(I) fluoride, bromide, and iodide salts generally inhibited cleavage (I- > Br- > F-). A halide anion-induced heavy-atom effect was indicated by monitoring anthracene photodegradation and by employing the hydroxyl radical (•OH) probe hydroxyphenyl fluorescein (HPF). These studies revealed that among no-salt controls and the eight halide salts, only NaCl and KCl enabled the anthracene to photosensitize the production of high levels of DNA-damaging reactive oxygen species (ROS). Pre-irradiation of N1-(anthracen-9-ylmethyl)ethane-1,2-diaminium dichloride at 350 nm increased the amounts of chloride salt-induced •OH detected by HPF in subsequent anthracene photoactivation experiments. Taking into consideration that •OH and other highly reactive ROS are extremely short-lived, this result suggests that the pre-irradiation step might lead to the formation of oxidized anthracene photoproducts that are exceedingly redox-active. The fluorometric probes HPF and Singlet Oxygen Sensor Green revealed that KCl concentrations ranging from 150 to 400 mM and from 100 to 400 mM, respectively, enhanced N1-(anthracen-9-ylmethyl)ethane-1,2-diaminium dichloride photosensitized •OH and singlet oxygen (1O2) production over no-salt controls. Considering the relatively high levels of Na+, K+, and Cl- ions that exist in the environment and in living organisms, our findings may be relevant to the phototoxic effects exhibited by anthracenes and other polycyclic hydrocarbons in vivo.

Latinx adolescents' trust in adults: A precursor to psychological well-being via mentoring relational quality and self-esteem.

This study aimed to test a longitudinal model of trust in adults and psychological well-being among Latinx adolescents, a population that has received little attention in the trust literature. The participants were urban, low-income Latinx (N = 294) students at two urban, Midwestern high schools who indicated they had at least one natural mentor in 9th grade. Participants completed surveys at two-time points, in 9th and 10th grade, and responded to measures of their feelings toward adults, quality of their natural mentoring relationships, self-esteem, intrinsic academic motivation, and coping self-efficacy. More trust in adults was indirectly, but not directly, associated with higher coping self-efficacy via higher mentoring relational quality and self-esteem. Positive expectations of adults may open Latinx youth to closeness in natural mentoring relationships and positive self-perceptions, which may, in turn, bolster coping ability.

The impact of social support on adolescent coping in the context of urban poverty.

OBJECTIVE: This study used a mixed method, prospective, multi-informant design to (a) identify coping strategies used by youth residing in urban poverty and (b) test whether these coping strategies buffer the effects of stress exposure when adult support is present and when absent. METHOD: There were 286 youth ages 10 to 16 (mean age at Time 1 = 13; 65% female; 34% male; 1% not identified; 46% African American; 25% Latino; 11% European American; 8% Asian American, 4% Mixed/Biracial, 6% Other) and their parents who participated. Thematic analyses were used to code adolescent interviews about protective factors to identify specific coping strategies used. Hierarchical regression analyses tested whether these coping strategies moderate the association between stress exposure and psychological symptoms for youth with and without adult support. RESULTS: Youth identified multiple coping strategies as protective including Expressing Oneself, Self-Soothing, Seeking Help, Seeking Safety, Distraction, Problem-Solving, Self-Care, and Avoidance. A number of these coping strategies (Expressing Oneself, Self-Soothing, Seeking Help, and Seeking Safety) attenuated the association between stressors and psychological symptoms over time for youth with adult support. For youth without adult support, a number of the strategies they identified as protective (Distraction, Problem-Solving, and Self-Care) accentuated the association between stress exposure and psychological symptoms over time. The only strategy that proved protective for youth without adult support was avoidance. CONCLUSIONS: Findings suggest that youth require adult support to effectively make use of a range of coping strategies and that avoidance is the sole effective strategy for youth without support. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

DNA Photocleavage in the Near-Infrared Wavelength Range by 2-Quinolinium Dicarbocyanine Dyes.

Here, we report the syntheses of two pentamethine cyanine dyes containing quinolinium rings and substituted with either hydrogen (3) or bromine (4) at the meso carbon. The electron withdrawing bromine atom stabilizes dye 4 in aqueous buffer, allowing complex formation to occur between the dye and double-helical DNA. UV-visible, CD, and fluorescence spectra recorded at low DNA concentrations suggest that dye 4 initially binds to the DNA as a high-order aggregate. As the ratio of DNA to dye is increased, the aggregate is converted to monomeric and other low-order dye forms that interact with DNA in a non-intercalative fashion. The brominated dye 4 is relatively unreactive in the dark, but, under 707-759 nm illumination, generates hydroxyl radicals that cleave DNA in high yield (pH 7.0, 22 °C). Dye 4 is also taken up by ES2 ovarian carcinoma cells, where it is non-toxic under dark conditions. Upon irradiation of the ES2 cells at 694 nm, the brominated cyanine reduces cell viability from 100 ± 10% to 14 ± 1%. Our results suggest that 2-quinolinium-based carbocyanine dyes equipped with stabilizing electron withdrawing groups may have the potential to serve as sensitizing agents in long-wavelength phototherapeutic applications.

Negative cognitive style and cortisol recovery accentuate the relationship between life stress and depressive symptoms.

When exposed to stressful life events, a significant number of adolescents will experience depressive symptoms. One model of depression suggests that individuals with a negative cognitive style are most vulnerable to depression following life stress. Alternatively, altered activation of the hypothalamic-pituitary-adrenal axis may explain vulnerability to depression following life stress. Each of these models plausibly explains the emergence of depressive symptoms during adolescence and have been investigated largely independently. The current study recruited a sample of urban adolescents (N = 179) to evaluate whether cortisol response to a laboratory stress induction and negative cognitive style are related and whether they independently interact with exposure to stressful life events to predict symptoms of depression. Negative cognitive style was not associated with cortisol response to the laboratory stressor. Rather, negative cognitive style and cortisol recovery independently interacted with stressful life events to predict current symptoms of depression. Results support a heterogeneous etiology of depression.

Violence and Vigilance: The Acute Effects of Community Violent Crime on Sleep and Cortisol.

The data combine objectively measured sleep and thrice-daily salivary cortisol collected from a 4-day diary study in a large Midwestern city with location data on all violent crimes recorded during the same time period for N = 82 children (Mage  = 14.90, range = 11.27-18.11). The primary empirical strategy uses a within-person design to measure the change in sleep and cortisol from the person's typical pattern on the night/day immediately following a local violent crime. On the night following a violent crime, children have later bedtimes. Children also have disrupted cortisol patterns the following morning. Supplementary analyses using varying distances of the crime to the child's home address confirm more proximate crimes correspond to later bedtimes.

Exposure to Community Violence and the Trajectory of Internalizing and Externalizing Symptoms in a Sample of Low-Income Urban Youth.

This study examined trajectories of psychopathology in a sample of low-income urban youth and tested exposure to community violence as a predictor of these trajectories. Self-report and parent-report survey measures of psychological problems and exposure to community violence were collected annually over 3 years from a sample of 364 fifth- to ninth-grade low-income urban youth (64% female; 95% youth of color). Linear growth models showed that youth experienced declines in both internalizing and externalizing symptoms across adolescence. Exposure to community violence was more strongly associated with externalizing symptoms than with internalizing symptoms but predicted declines in both types of symptoms. Results also indicated that youth reported more internalizing and externalizing symptoms than their parents reported for them. Exposure to community violence may explain unique trajectories of mental health problems among low-income urban youth. In addition, youth efforts to adopt a tough façade in the face of community violence could lead to higher rates of externalizing problems relative to internalizing problems, whereas desensitization processes may better explain reductions in both types of symptoms over time. Finally, youth report may be more valid than parent report in the context of urban poverty.

Taking on the stress-depression link: Meaning as a resource in adolescence.

We investigated how meaning in life affects the link between stress and depression symptoms in adolescents. Adolescents (N = 177; 58.4% female, mean age = 14.75 years) reported on their meaning in life, exposure to stressors, and depression symptomatology. Higher meaning in life predicted lower depression symptoms. Importantly, meaning in life moderated the relationship between stress exposure and depressive symptoms: stress exposure was associated with higher depression when meaning in life was low, when meaning in life was high, there was no association between stressors and depression. These findings indicate the importance of having a sense of meaning in life adolescence. A positive relationship was found between stress exposure and depression symptomatology levels at a time-point seven months earlier. This lends a longitudinal perspective; meaning in life moderated a relationship that had been present for seven months. Therapeutic implications for protecting at-risk youth are discussed.

Daily affective experiences predict objective sleep outcomes among adolescents.

Adolescence is a sensitive period for changes in both sleep and affect. Although past research has assessed the association between affect and sleep among adolescents, few studies have examined both trait (typical) and day-to-day changes in affect, and fewer still have specifically examined negative social evaluative emotions (e.g. embarrassment) in relation to sleep. Both between- and within-person variations in daily affect were examined in relation to four objectively-measured sleep outcomes (sleep hours; sleep latency; sleep efficiency; and length of wake bouts) among adolescents. Participants (N = 77 high-school students; 42.9% female; M = 14.37 years) wore an actiwatch and completed daily-diaries for 3 days. The results of hierarchical linear models (controlling for age, gender, race, ethnicity, parental employment status, income, puberty and caffeine) indicated that negative social evaluative emotions and high-arousal affective experiences generally predicted poor sleep outcomes, whereas low-arousal affective experiences were associated with good sleep outcomes. Specifically, at the person level, adolescents reporting higher negative social evaluative emotions had shorter average sleep hours, and those experiencing higher anxiety­nervousness had longer wake bouts. In addition, individuals experiencing more dysphoria (sad, depressed, lonely) had longer average sleep hours and shorter wake bouts, while those experiencing more calmness had shorter sleep latencies. At the within-person level, individuals had longer sleep latencies following days that they had experienced high-arousal positive affect (e.g. excitement), and had longer wake bouts following days they had experienced more negative social evaluative emotions. The results highlight the detrimental effects of negative social evaluative emotions and high-arousal affective states for adolescent sleep.

Real-time electrochemical LAMP: a rational comparative study of different DNA intercalating and non-intercalating redox probes.

We present a comparative study of ten redox-active probes for use in real-time electrochemical loop-mediated isothermal amplification (LAMP). Our main objectives were to establish the criteria that need to be fulfilled for minimizing some of the current limitations of the technique and to provide future guidelines in the search for ideal redox reporters. To ensure a reliable comparative study, each redox probe was tested under similar conditions using the same LAMP reaction and the same entirely automatized custom-made real-time electrochemical device (designed for electrochemically monitoring in real-time and in parallel up to 48 LAMP samples). Electrochemical melt curve analyses were recorded immediately at the end of each LAMP reaction. Our results show that there are a number of intercalating and non-intercalating redox compounds suitable for real-time electrochemical LAMP and that the best candidates are those able to intercalate strongly into ds-DNA but not too much to avoid inhibition of the LAMP reaction. The strongest intercalating redox probes were finally shown to provide higher LAMP sensitivity, speed, greater signal amplitude, and cleaner-cut DNA melting curves than the non-intercalating molecules.

Development of an Empirically Based Preventive Intervention for Depression in Preadolescent African American Girls.

We describe the development, feasibility, and acceptability of a novel preventive intervention for depression in African American girls living in urban poverty. Our approach targeted individual and interpersonal vulnerabilities that have been shown to confer risk for depression in samples of African American girls living in low-income, urban settings, including suppression of negative emotion and lack of assertiveness with peers, memory for positive emotion, active coping, and family connection. Focus groups and an open trial were conducted to refine the goals and mechanisms for skill building. A randomized controlled trial (RCT) of the new program (Cities Mother-Daughter Project) was conducted with 3rd-5th grade students from Chicago Public Schools (CPS). Three cycles of screening, randomization, and deployment were conducted to assess feasibility, satisfaction, and usability. Results indicate that feasibility was weak; whereas, satisfaction and usability were high. Future directions for testing efficacy are discussed.

The Costs and Benefits of Active Coping for Adolescents Residing in Urban Poverty.

The present study addresses the lack of specificity and diversity highlighted in recent stress literature reviews by examining active coping in relationships between exposure to violence and internalizing and externalizing symptoms in a sample of urban youth from predominantly low-income, African American and Latino backgrounds. Two hundred and forty-one youth (mean age at Time 1 = 13 years; 66 % female; 41 % African American, 28 % Latino, 14 % European American, 6 % Asian American, 7 % mixed/biracial, 1 % American Indian/native American, .5 % Hawaiian/Pacific Islander, 2 % other) and their parents participated in this three-wave study. Hierarchical regression analyses tested for moderation, and a cross lag panel path analysis tested for mediation. The results provide greater support for active coping as a variable that changes the relationship between exposure to community violence and externalizing symptoms, or moderation, rather than one that explains or mediates it. Further, specificity did not emerge for type of psychological outcome but did emerge for gender, such that active coping exacerbated the association between exposure to community violence and both internalizing and externalizing symptoms for girls, but not boys. These findings highlight the importance of contextual and demographic factors in influencing stress and coping processes during adolescence.

Tuning Cerium(IV)-Assisted Hydrolysis of Phosphatidylcholine Liposomes under Mildly Acidic and Neutral Conditions.

With the goal of designing a lysosomal phospholipase mimic, we optimized experimental variables to enhance Ce(IV) -assisted hydrolysis of phosphatidylcholine (PC) liposomes. Our best result was obtained with the chelating agent bis-tris propane (BTP). Similar to the hydrolytic enzyme, Ce(IV) -assisted hydrolysis of PC phosphate ester bonds was higher at lysosomal pH (∼4.8) compared to pH 7.2. In the presence of BTP, the average cleavage yield at ∼pH 4.8 and 37 °C was: 67±1 %, 5.7-fold higher than at ∼pH 7.2 and roughly equivalent to the percent of phospholipid found on the metal-accessible exo leaflet of small liposomes. No Ce(IV) precipitation was observed. When BTP was absent, there was significant turbidity, and the amount of cleavage at ∼pH 4.8 (69±1 %) was 2.1-fold higher than the yield obtained at ∼pH 7.2. Our results show that BTP generates homogenous solutions of Ce(IV) that hydrolyze phosphatidylcholine with enhanced selectivity for lysosomal pH.

Oxidative cleavage of DNA by pentamethine carbocyanine dyes irradiated with long-wavelength visible light.

Here we report the synthesis of seven symmetrical carbocyanine dyes in which two nitrogen-substituted benz[e]indolium rings are joined by a pentamethine bridge that is meso-substituted with chlorine or bromine versus hydrogen. The heteroatom of benz[e]indolium is modified with a phenylpropyl, methyl, or cationic quaternary ammonium group. In reactions containing micro molar concentrations of halogenated dye, irradiation at 575, 588, 623, or 700nm produces good photocleavage of plasmid DNA. UV-visible spectra show that the carbocyanines are in their H-aggregated and monomeric forms. Scavenger experiments point to the involvement of singlet oxygen and hydroxyl radicals in DNA photocleavage.

Mediating effects of parent-child relationships and body image in the prediction of internalizing symptoms in urban youth.

Youth are faced with many stressful interpersonal, contextual, and identify development related challenges that contribute to the increased risk of negative outcomes during adolescence. The current study examined two important factors related to youth's development and well-being: parent-child attachment and negative body image. Specifically, the current study examined body image as one mechanism responsible for the effect that mother and father attachment has on internalizing symptoms in a sample of low-income, ethnic minority youth. Additionally, differences across gender and ethnic/racial groups were examined. Participants included 140 (71 % female) ages 10-16 at baseline recruited from urban public schools in Chicago with high percentages of low-income students. The current sample was ethnically diverse (41 % African American, 30 % Latino, 16 % European American, 6 % Biracial, 6 % Asian, and 1 % other). Participants completed measures of their relationships with their mothers and fathers, negative body image, and internalizing symptoms across two periods of time separated by approximately 1 year. Results showed that body image mediated the relation between both mother and father attachment and internalizing symptoms. These results were further moderated by race/ethnicity, but not by sex. For African American participants, mother attachment was related to internalizing symptoms through negative body image while for Latinos, paternal attachment was related to internalizing symptoms through negative body image. Although maternal attachment had direct effects on internalizing symptoms for Latinos, negative body image did not mediate this relationship. These results support an integrative model in which interpersonal risk lays the foundation for the development of cognitive risk, which in turn leads to internalizing symptoms for urban youth.

Sports Participation, Frequency, and Competence Differentially Impact Youth Depressive, Anxious, and Somatic Symptoms: Gender, Neighborhood, and Sports Type Effects.

Mental health problems are prevalent in adolescence, but sports participation may offer mental health benefits through this developmental period and beyond. Characteristics of sports participation including perceived frequency and competence may differentially predict adolescent depressive, anxious, and somatic symptoms over time and results may further vary according to gender, neighborhood context, and type of sport engagement. Data were collected at two time-points six months apart from an ethnically diverse sample of adolescents (N = 183, female = 51%). Youth sports participation and symptoms were measured using the Youth Self-Report (YSR; Achenbach & Rescorla, 2001). Path analyses were used to test for main and moderating effects of sports on symptoms. Results showed that categorical sports participation did not prospectively predict any type of internalizing symptoms, but perceived frequency and competence did. Competence predicted lower levels of symptoms while frequency predicted higher levels of symptoms. These results were further moderated by gender, neighborhood, and sport type such that frequency and competence predicted symptoms for girls and for youth in more resourced neighborhoods and who participated in team sports. These findings highlight the impact that sports participation can have on adolescent mental health in an ethnically diverse sample of urban youth.

Recurrent deletions and reciprocal duplications of 10q11.21q11.23 including CHAT and SLC18A3 are likely mediated by complex low-copy repeats.

We report 24 unrelated individuals with deletions and 17 additional cases with duplications at 10q11.21q21.1 identified by chromosomal microarray analysis. The rearrangements range in size from 0.3 to 12 Mb. Nineteen of the deletions and eight duplications are flanked by large, directly oriented segmental duplications of >98% sequence identity, suggesting that nonallelic homologous recombination (NAHR) caused these genomic rearrangements. Nine individuals with deletions and five with duplications have additional copy number changes. Detailed clinical evaluation of 20 patients with deletions revealed variable clinical features, with developmental delay (DD) and/or intellectual disability (ID) as the only features common to a majority of individuals. We suggest that some of the other features present in more than one patient with deletion, including hypotonia, sleep apnea, chronic constipation, gastroesophageal and vesicoureteral refluxes, epilepsy, ataxia, dysphagia, nystagmus, and ptosis may result from deletion of the CHAT gene, encoding choline acetyltransferase, and the SLC18A3 gene, mapping in the first intron of CHAT and encoding vesicular acetylcholine transporter. The phenotypic diversity and presence of the deletion in apparently normal carrier parents suggest that subjects carrying 10q11.21q11.23 deletions may exhibit variable phenotypic expressivity and incomplete penetrance influenced by additional genetic and nongenetic modifiers.

A prospective comparison of moderating relationships among stressors, hopelessness, and internalizing symptoms in low-income urban youth with asthma.

There are many risk factors associated with the development of internalizing symptoms in low-income urban youth, and youth with asthma appear to be at greater risk for experiencing stressors in multiple domains. The purpose of the current study was to examine stressors, hopelessness, and the interaction between them, as predictors of trajectories of anxious/depressed and withdrawn symptoms over a 4-year period of adolescence. Participating in the study were 53 youth from Chicago public schools, the majority of whom identified themselves as African American or Latino. Multi-level modeling was used to examine major life events, daily hassles, exposure to violence, poverty, and hopelessness as predictors of both types of symptoms. Major life events and exposure to violence predicted anxious/depressed symptoms but not withdrawn symptoms. Hopelessness predicted both types of symptoms and further interacted with major life events to predict both anxious/depressed and withdrawn symptoms. Hopelessness also moderated the effects of daily hassles on anxious/depressed symptoms and poverty on withdrawn symptoms. Results of this study provide insight into the psychosocial risk factors associated with the experience of asthma in urban adolescents.

Evaluating metal ion salts as acid hydrolase mimics: metal-assisted hydrolysis of phospholipids at lysosomal pH.

Niemann-Pick disease and drug-induced phospholipidosis are lysosomal storage disorders in which there is an excessive accumulation of sphingomyelin in cellular lysosomes. Here we have explored the possibility of developing metal-based therapeutic agents to reverse phospholipid build-up through phosphate ester bond hydrolysis at lysosomal pH (~4.8). Towards this end, we have utilized a malachite green/molybdate-based colorimetric assay to quantitate the inorganic phosphate released upon the hydrolysis of sphingomyelin by twelve d- and f-block metal ion salts. In reactions conducted at 60 °C, the yields produced by the cerium(IV) complex Ce(NH(4))(2)(NO(3))(6) were superior. An Amplex(®) Red-based colorimetric assay and mass spectrometry were then employed to detect choline. The data consistently showed that Ce(IV) hydrolyzed sphingomyelin more efficiently at lysosomal pH: i.e., yields of choline and phosphate were 54 ± 4 and 22 ± 5 % at pH ~ 4.8, compared to 8 ± 1 and 5 ± 2 % at pH ~ 7.2. Hydrolysis at 60 °C could be significantly increased by converting sphingomyelin vesicles to mixed lipid vesicles and mixed micelles of Triton X-100. We then utilized cerium(IV) to cleave sphingomyelin at 37 °C (no Triton X-100). Although choline and phosphate levels were relatively low, hydrolysis continued to be considerably more efficient at lysosomal pH. A side by side comparison to phosphatidylcholine was then made. While the yields of choline and phosphate produced by phosphatylcholine were higher, the ratio of pH ~ 4.8 hydrolysis to pH ~ 7.2 hydrolysis was usually more favorable for sphingomyelin (37 and 60 °C).