Protocol for project MIME: Motivation, inflammation, and Mood in Emerging Adults

Background: Atypical inflammatory biology is gaining evidence as a risk factor for mood psychopathology; however, little work has attempted to integrate inflammation into extant psychosocial frameworks of risk. Recent work using secondary data analysis has investigated the possibility of an immunocognitive model of mood disorders, in which cognitive vulnerabilities (i.e., rumination on positive or negative affect) increase the effect that arousal-related characteristics (e.g., reward sensitivity) have on inflammatory biology in ways that may confer risk for depression and hypo/mania symptoms. Project MIME (Motivation, Inflammation, and Mood in Emerging Adults) was designed to test this model in the context of a novel, reward-salient stressor (the Anger Incentive Delay Task, AIDT). Methods: This NIMH-funded study will result in a dataset of approximately 100 college undergraduates from a large university in Pennsylvania, United States of America. Eligible participants are recruited from an online screener, have to be 18–22 years old, fluent in English, and successfully answer several items designed to test whether participants randomly answer questions on the screener. Eligible participants are invited to an in-person visit in which they completed the AIDT, blood draws pre- and 50 minutes post-AIDT, and self-report questionnaires. Participants also complete a set of online questionnaires two weeks after the in-person visit. Discussion: Consistent with calls from the NIH director, this study seeks to diversify the tools used in stress research by validating a novel reward-salient stressor (in contrast to the field's reliance on social stressors) with respect to affective and immunological stress reactivity. In addition to this methodological goal, Project MIME is the first study specifically designed to test the immunocognitive model of mood psychopathology. Given the integration of several malleable treatment targets (approach behavior, emotion regulation, inflammation) into this model, results from this study could inform comprehensive, flexible intervention strategies for mood disorder prevention and treatment

Bioaccumulation and ecotoxicity of carbon nanotubes

Carbon nanotubes (CNT) have numerous industrial applications and may be released to the environment. In the aquatic environment, pristine or functionalized CNT have different dispersion behavior, potentially leading to different risks of exposure along the water column. Data included in this review indicate that CNT do not cross biological barriers readily. When internalized, only a minimal fraction of CNT translocate into organism body compartments. The reported CNT toxicity depends on exposure conditions, model organism, CNT-type, dispersion state and concentration. In the ecotoxicological tests, the aquatic organisms were generally found to be more sensitive than terrestrial organisms. Invertebrates were more sensitive than vertebrates. Single-walled CNT were found to be more toxic than double-/multi-walled CNT. Generally, the effect concentrations documented in literature were above current modeled average environmental concentrations. Measurement data are needed for estimation of environmental no-effect concentrations. Future studies with benchmark materials are needed to generate comparable results. Studies have to include better characterization of the starting materials, of the dispersions and of the biological fate, to obtain better knowledge of the exposure/effect relationships

The influence of salinity on the effects of Multi-walled carbon nanotubes on polychaetes

Salinity shifts in estuarine and coastal areas are becoming a topic of concern and are one of the main factors influencing nanoparticles behaviour in the environment. For this reason, the impacts of multiwalled carbon nanotubes (MWCNTs) under different seawater salinity conditions were evaluated on the common ragworm Hediste diversicolor, a polychaete species widely used as bioindicator of estuarine environmental quality. An innovative method to assess the presence of MWCNT aggregates in the sediments was used for the first time. Biomarkers approach was used to evaluate the metabolic capacity, oxidative status and neurotoxicity of polychaetes after long-term exposure. The results revealed an alteration of energy-related responses in contaminated polychaetes under both salinity conditions, resulting in an increase of metabolism and expenditure of their energy reserves (lower glycogen and protein contents). Moreover, a concentration-dependent toxicity (higher lipid peroxidation, lower ratio between reduced and oxidized glutathione and activation of antioxidant defences and biotransformation mechanisms) was observed in H. diversicolor, especially when exposed to low salinity. Additionally, neurotoxicity was observed by inhibition of Cholinesterases activity in organisms exposed to MWCNTs at both salinities.publishe

Cognitive Vulnerability to Depression in Canadian and Chinese Adolescents

The goal of the current study was to compare diathesis-stress and transactional models of cognitive vulnerability to depression in samples of Canadian (n = 118) and Chinese (n = 405) adolescents. We utilized a six-month multi-wave, longitudinal design in order to examine whether (a) perceived control moderated the association between the occurrence of dependent interpersonal stressors and subsequent increases in depressive symptoms (i.e., a diathesis-stress perspective) and (b) dependent interpersonal stressors mediated the association between perceived control and subsequent increases in depressive symptoms (i.e., a transactional perspective). Results from idiographic, time-lagged, hierarchical linear modeling analyses indicated that for Canadian adolescents both diathesis-stress and transactional models were significant predictors of depressive symptomology. When examining the diathesis-stress model, boys, but not girls, who reported lower perceived control, reported higher levels of depressive symptoms following the occurrence of dependent interpersonal stress. Gender differences, however, were not present in the transactional model. In contrast, transactional, but not diathesis-stress, models were significant in Chinese adolescents, and gender differences did not emerge. Overall, these results may reflect culturally-relevant differences in the etiology of depression in Canadian and Chinese adolescents

Depressive symptoms during adolescence:comparison between epidemiological and high risk sampling

PURPOSE: Both epidemiological (unselected) and high risk (screening on known risk criteria) samplings have been used to investigate the course of affective disorders. Selecting individuals on multiple risk criteria may create a sample not comparable to individuals with similar risk criteria within the general population. This study compared depressive symptoms across the two sampling methods to test this possibility. METHODS: The high risk Cambridge Hormones and Moods Project (CHAMP) screened and recruited adolescents aged 12 to 16. A total of 905 (710 high risk) individuals participated and were reassessed at three follow-ups. The ROOTS epidemiological sample consisted of 1,208 14-year-olds reassessed at 15.5 and 17 years. The risk profile for CHAMP was recreated in the ROOTS study. Both samples completed the Moods and Feelings Questionnaire, a self-report measure of current depressive symptoms. RESULTS: Comparing individuals with the same high risk profiles across the CHAMP and ROOTS studies revealed no significant differences in mean depression scores. Combining the samples revealed that for females, mean depression scores were maintained from 12 to 15 years then declined by 17 years. For males, scores declined from 12 throughout adolescence. High risk status led to consistently higher levels of depressive symptoms in female adolescents but result in little change within male adolescents. CONCLUSIONS: The high risk design recruited adolescents with a depression symptoms profile comparable to the general population for both sexes. High risk status may alter the trajectory of depressive symptoms in female adolescents only. Males may be less sensitive to recent adversity