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This study examined bidirectional relations between television exposure and effortful control accounting for the effects of family contextual risk factors. METHODS: Data were from a sample (N=306) of parents and their preschool-age children (T1 M = 36 mos. in 2008–2010) assessed four times, once every 9 mos. RESULTS: At T1, adolescent parent status predicted lower child delay ability (DA), and maternal depression predicted higher TV time. Above these effects, higher T1 and T2 child executive control (EC) prospectively predicted lower T2 and T3 TV time, while higher T1 TV time predicted lower T2 EC. Higher EC at T4 predicted fewer total problems, greater social competence, and greater academic readiness at T4, and higher TV time at T4 predicted lower academic readiness. DA was unrelated to TV time or adjustment. CONCLUSION: Findings suggest executive control and TV time predict changes in each other in early childhood, and in turn, executive control predicts better child adjustment while TV time might be more relevant for academic readiness. Moreover, family risk factors appear to play a role in both TV viewing time and effortful control.

While appraisal and coping are known to impact adolescent psychopathology, more vulnerable or resilient responses to stress may depend on individual temperament. This study examined early life temperament as a moderator of the prospective relations of pre-adolescent appraisal and coping with adolescent psychopathology. The sample included 226 (62% female, 14–15 years) adolescents with assessments starting at 3 years of age. Adolescents were predominately White (12% Black 9% Asian, 11% Latinx, 4% Multiracial, and 65% White). Observed early-childhood temperament (fear, frustration, executive control, and delay ability) were tested as moderators of pre-adolescent coping (active and avoidant) and appraisal (threat, positive) on internalizing and externalizing symptoms during the pandemic. Interaction effects were tested using regression in R. Sex and family context of stress were covariates. Early-childhood temperament was correlated with pre-adolescent symptoms, however, pre-adolescent appraisal and coping but not temperament predicted adolescent psychopathology. Frustration moderated the relations of active and avoidant coping and positive appraisal to symptoms such that coping and appraisal related to lower symptoms only for those low in frustration. Executive control moderated the associations of avoidant coping with symptoms such that avoidance reduced the likelihood of symptoms for youth low in executive control. Findings underscore the role of emotionality and self-regulation in youth adjustment, with the impact of coping differing with temperament. These findings suggest that equipping youth with a flexible assortment of coping skills may serve to reduce negative mental health outcomes.

Children exposed to cumulative risk (CR) are more likely to have poor physical and psychological health across the lifespan. CR may contribute to children's adjustment, in part through its effects on appraisal and coping. Further, child temperament may alter the effects of CR on appraisal and coping.This study investigated the interactive and prospective effects of CR and temperament on children's appraisal and coping strategies.In this secondary data analysis using a community sample (N=306) of preadolescents (M age = 9.5 at T1), structural equations models were conducted to examine temperament negative emotionality (NE) and effortful control (EC) as moderators of the effect of CR on both levels and proportional use of positive and threat appraisals, and active and avoidant coping.Children higher in NE used more threat appraisal and avoidant coping, whereas children higher in EC used less threat appraisal concurrently and decreased in their use of threat appraisal across 1 year. Both NE and EC altered the prospective effect of CR on appraisal and coping.Findings suggest temperament alters the effect of CR on appraisal and coping, implicating EC as a resource and NE as a vulnerability in changes in appraisal and coping during preadolescence.

BACKGROUND: A survey was developed to characterize disease incidence, common pathology lesions, environmental characteristics, and nutrition programs within captive research marmoset colonies. METHODS: 17 research facilities completed the electronic survey. RESULTS: Nutritional management programs varied amongst research institutions housing marmosets; eight primary base diets were reported. The most common clinical syndromes reported were gastrointestinal (GI) disease (i.e. inflammatory bowel disease (IBD) like disease, chronic lymphocytic enteritis (CLE), chronic malabsorption, chronic diarrhea), metabolic bone disease or fracture, infectious diarrhea, and oral disease (tooth root abscesses, gingivitis, tooth root resorption). The five most common pathology morphologic diagnoses were colitis, nephropathy/ nephritis, enteritis, chronic lymphoplasmacytic enteritis, and cholecystitis. Obesity was more common (average 20% of a reporting institution’s population) than thin body condition (average 5%). CONCLUSIONS: Through review of current practices, we aim to inspire development of evidence based practices to standardize husbandry and nutrition practices for marmoset research colonies.

The optimal choice of euthanasia method for laboratory rodents depends on a number of factors, including the scientific goals of the study, the need to minimize animal pain and/or distress, applicable guidelines and laws, the training and proficiency of personnel, and the safety and emotional needs of the personnel performing the euthanasia. This manuscript aims to provide guidance to researchers so they may select the method of euthanasia that results in minimal experimental confounds, such as the creation of artifact and alteration of tissues and analytes. Specific situations addressed include euthanasia of large numbers of rodents and euthanasia of neonates. Recent literature supports the notion of significant strain-dependent differences in response to euthanasia methods such as CO2 inhalation. To assist researchers in selecting a strain-appropriate method of euthanasia, the authors present a summary of methodologies for assessing the effectiveness of euthanasia techniques, including elements and parameters for a scoring rubric to assess them.

This study presents recommendations for intramuscular injection into the caudal thigh muscle of mice according to analysis of in vivo imaging of intramuscularly injected iohexol, a radiocontrast agent commonly used in CT imaging. An experienced laboratory animal technician using a Hamilton syringe intramuscularly injected iohexol into isoflurane-anesthetized female and male BALB/c mice. Injected volumes (25, 50, 100, and 200 μL) underwent CT scanning at 9 time points over a 3-h period. The distribution of the injectate in the muscles of the rear leg was examined over time for each volume group. Results indicated that 25- and 50-μL volumes remain intramuscularly. At 100 μL, mild to moderate leakage into the extramuscular tissues occurred. At 200 μL, leakage into the extramuscular tissues was moderate to severe. Our results suggest volumes of 50 μL or less are recommended for the caudal thigh muscles of mice when intramuscular pharmacokinetics are needed; volumes greater than 50 μL display variable distribution into extramuscular tissues, thus potentially yielding different pharmacokinetic profiles.

Adolescence is a dynamic stage of development during which individuals transition into more challenging academic contexts, navigate increasingly complex peer and romantic relationships, and take on adult responsibilities, all while experiencing significant neuro-hormonal changes associated with puberty. These changes put adolescents at risk for myriad emotional and behavioral problems, known to markedly escalate during adolescence. Underage alcohol use, in particular, is increasingly common during adolescence (Johnston et al., 2014a), and contributes to risky sexual behavior, delinquency, school drop-out, and substance use disorders (Brown et al., 2009; Newcomb & Bentler, 1988; Trim et al., 2007). Alcohol use is also highly comorbid with anxiety and depressive disorders (NIDA, 2010). Two theoretical models have been advanced to account for this comorbidity. The self-medication model posits that individuals with pre-existing internalizing symptoms use alcohol to cope with their emotional distress and soothe its physiological concomitants (Trim et al., 2007; Wolitzky-Taylor et al., 2012). Support for the prospective effect of internalizing symptoms on alcohol use has been mixed (Fergusson et al., 2009; Hallfors et al., 2005; Lansford et al., 2008; Maslowsky et al., 2014; Wolitzky-Taylor et al., 2012). The alcohol-induced disruption model posits that alcohol use leads to internalizing symptoms by: (a) impeding the development of effective coping and self-regulatory skills; (b) inducing neurotoxic effects that impair cognitive functioning, which creates school-related stress; and (c) alcohol use dysregulates reward mechanisms in the brain, causing adolescents to focus on acquiring alcohol rather than engaging in more adaptive activities that reduce risk for depression and anxiety (Brook et al., 2002; King et al., 2004; Trim et al., 2007). Few studies have tested these mediation pathways, and even the prospective effect of alcohol use on internalizing problems in adolescence is not well established, especially in non-clinical samples (Frojd et al., 2011; Mason et al., 2008). The present research examined cross-lagged relations between frequency of alcohol use and internalizing symptoms, using data from a longitudinal study of 674 Mexican-origin youth (50% female) assessed at ages 14 and 16. The study extends previous research in several ways. First, whereas most prior studies examined concurrent associations between alcohol use and internalizing symptoms, we used longitudinal data to examine reciprocal prospective relations and thus establish the temporal order of the effects. Second, our measure of internalizing problems assesses symptoms unique to anxiety and depression, as well as symptoms common to the disorders, allowing us to elucidate which specific aspects of anxiety and depression are more or less relevant to alcohol use. This is important because the effects of depression on alcohol use appear to be more robust than the effects of anxiety (Hallfors et al., 2005; Hussong & Chassin, 1994; Kaplow et al., 2010), but is difficult to draw conclusions from this literature because many measures of depression include some anxiety content and many measures of anxiety include some depressive content. Third, whereas many prior studies have used clinical samples, our community-based sample allows for more generalizable inferences about how alcohol use and anxiety/depression are associated during normative adolescent development. Finally, we focused on a specific ethnic minority group, Mexican-origin individuals, that remains understudied in the context of alcohol involvement and internalizing problems, despite their growing representation in the population (U.S. Census, 2014), their early onset of alcohol use (Johnston et al., 2014b), and their increased vulnerability to psychiatric and substance use disorders the longer they are exposed to American society (Vega et al., 1998; 2000). Although the developmental pathways characterizing Mexican-origin and European-origin youth sometimes differ, in the present context we expected to find the same pattern of results observed in prior research. This expectation is based on the fact that the mediating mechanisms posited by the self-medication and alcohol-induced disruption models reflect basic processes that are unlikely to be culture specific; youth from all ethnic groups are likely to derive some self-medicating benefit from alcohol use and, similarly, alcohol use is likely to lead to impaired self-regulatory skills, neurotoxic effects on brain development, and dysregulated reward processes. Thus, we predicted that alcohol use and internalizing symptoms would be reciprocally related over time, such that alcohol use at age 14 would contribute to subsequent increases in anxiety/depressive symptoms from age 14 to 16, and anxiety and depressive symptoms at age 14 would contribute to subsequent increases in alcohol use from age 14 to 16. Establishing the generalizability of these reciprocal associations to Mexican-origin youth has important implications. Theoretically, it would suggest that the developmental pathways linking these factors are not culture-specific but rather reflect more basic processes. Practically, it would suggest that intervention programs targeting these pathways (e.g., trying to reduce alcohol use by reducing internalizing problems or improving coping skills) are likely to be effective with Mexican-origin youth. In contrast, if our results differ from prior research, this would highlight the possibility of culture-specific developmental pathways, and suggest that factors unique to Mexican-origin youth exacerbate or diminish the link between internalizing symptoms and alcohol use. For example, the hypothesized pathways may be weaker for first-generation (vs. more acculturated) immigrants, given that first-generation youth are less likely to turn to substance use despite experiencing heightened levels of stress relative to latter generation youth (Garcia-Coll & Marks, 2011). To evaluate this possibility, we tested whether generational status moderates the association between internalizing symptoms and alcohol use. Finally, because the association between internalizing symptoms and alcohol use can be influenced by co-occurring externalizing symptoms (Colder et al., 2013), we also examined the effects of internalizing symptoms after controlling for a measure of externalizing problems.

Compassion, professional ethics, and public sensitivity require that animals are euthanized humanely and appropriately under both planned and emergent situations. According to the 2013 AVMA Guidelines for the Euthanasia of Animals, intraperitoneal injection of ethanol is “acceptable with conditions” for use in mice. Because only limited information regarding this technique is available, we sought to evaluate ethanol by using ECG and high-definition video recording. Mice (n = 85) and rats (n = 16) were treated with intraperitoneal ethanol (70% or 100%), a positive-control agent (pentobarbital–phenytoin combination [Pe/Ph]), or a negative-control agent (saline solution). After injection, animals were assessed for behavioral and physiologic responses. Pain-assessment techniques in mice demonstrated that intraperitoneal injection of ethanol was not more painful than was intraperitoneal Pe/Ph. Median time to loss of consciousness for all mice that received ethanol or Pe/Ph was 45 s. Median time to respiratory arrest was 2.75, 2.25, and 2.63 min, and time (mean ± SE) to cardiac arrest was 6.04 ± 1.3, 2.96 ± 0.6, and 4.03 ± 0.5 min for 70% ethanol, 100% ethanol, and Pe/Ph, respectively. No mouse that received ethanol or Pe/Ph regained consciousness. Although successful in mice, intraperitoneal ethanol at the doses tested (9.2 to 20.1 g/kg) was unsuitable for euthanasia of rats (age, 7 to 8 wk) because of the volume needed and prolonged time to respiratory effects. For mice, intraperitoneal injection of 70% or 100% ethanol induced rapid and irreversible loss of consciousness, followed by death, and should be considered as “acceptable with conditions.”

Calcium influx through L-type voltage-gated calcium channels (VGCC) is required for ERK activation induced by GnRH in pituitary gonadotropes. The current studies investigate VGCC-sensitive catalytic activities that may lie upstream of ERKs within the GnRH signaling network. Ion exchange fractionation of alphaT3-1 cell lysates subjected to anti-phosphotyrosine Western blot analysis revealed a nifedipine-sensitive activity that colocalized with proline-rich tyrosine kinase (Pyk) 2 immunoreactivity. Phosphorylated Pyk2 was present in alphaT3-1 cells after GnRH agonist administration for a time course that lasted up to 4 h. Pyk2 phosphorylation was also evident in gonadotropes in vivo after administration of a bolus of GnRH. Knockdown of Pyk2 using specific small interfering RNAs revealed that Pyk2 contributed to modulation of GnRH-induced ERK but not c-Jun N-terminal kinase activation. Using pharmacological approaches, calmodulin (Cam) was also demonstrated to be required for the phosphorylation of Pyk2. Pyk2 was shown to bind specifically to a Cam agarose affinity column in a calcium-dependent manner, suggesting Cam and Pyk2 are capable of forming a complex. Specific mutation of a putative Cam binding motif within the catalytic domain of Pyk2 blocked association with Cam and uncoupled Pyk2's ability to activate ERK-dependent gene transcription. Thus, GnRH induces Pyk2 tyrosine phosphorylation dependent upon calcium flux within gonadotropes. Furthermore, association of Pyk2 and Cam may be required to mediate the effects of calcium on Pyk2 phosphorylation and subsequent activation of ERKs by GnRH.