ERIC Educational Resources Information Center
Valente, Matthew J.; Gonzalez, Oscar; Miocevic, Milica; MacKinnon, David P.
2016-01-01
Methods to assess the significance of mediated effects in education and the social sciences are well studied and fall into two categories: single sample methods and computer-intensive methods. A popular single sample method to detect the significance of the mediated effect is the test of joint significance, and a popular computer-intensive method…
SPSS and SAS procedures for estimating indirect effects in simple mediation models.
Preacher, Kristopher J; Hayes, Andrew F
2004-11-01
Researchers often conduct mediation analysis in order to indirectly assess the effect of a proposed cause on some outcome through a proposed mediator. The utility of mediation analysis stems from its ability to go beyond the merely descriptive to a more functional understanding of the relationships among variables. A necessary component of mediation is a statistically and practically significant indirect effect. Although mediation hypotheses are frequently explored in psychological research, formal significance tests of indirect effects are rarely conducted. After a brief overview of mediation, we argue the importance of directly testing the significance of indirect effects and provide SPSS and SAS macros that facilitate estimation of the indirect effect with a normal theory approach and a bootstrap approach to obtaining confidence intervals, as well as the traditional approach advocated by Baron and Kenny (1986). We hope that this discussion and the macros will enhance the frequency of formal mediation tests in the psychology literature. Electronic copies of these macros may be downloaded from the Psychonomic Society's Web archive at www.psychonomic.org/archive/.
Huang, Yen-Tsung; Pan, Wen-Chi
2016-06-01
Causal mediation modeling has become a popular approach for studying the effect of an exposure on an outcome through a mediator. However, current methods are not applicable to the setting with a large number of mediators. We propose a testing procedure for mediation effects of high-dimensional continuous mediators. We characterize the marginal mediation effect, the multivariate component-wise mediation effects, and the L2 norm of the component-wise effects, and develop a Monte-Carlo procedure for evaluating their statistical significance. To accommodate the setting with a large number of mediators and a small sample size, we further propose a transformation model using the spectral decomposition. Under the transformation model, mediation effects can be estimated using a series of regression models with a univariate transformed mediator, and examined by our proposed testing procedure. Extensive simulation studies are conducted to assess the performance of our methods for continuous and dichotomous outcomes. We apply the methods to analyze genomic data investigating the effect of microRNA miR-223 on a dichotomous survival status of patients with glioblastoma multiforme (GBM). We identify nine gene ontology sets with expression values that significantly mediate the effect of miR-223 on GBM survival. © 2015, The International Biometric Society.
Francesconi, Marta; Minichino, Amedeo; Carrión, Ricardo E; Chiaie, Roberto Delle; Bevilacqua, Arturo; Parisi, Maurizio; Rullo, Santo; Bersani, Francesco Saverio; Biondi, Massimo; Cadenhead, Kristin
2016-12-30
A large body of studies provides evidence for a link between neurocognition, theory of mind (ToM) and functioning in psychotic spectrum disorders (PSDs), with ToM mediating the effect that neurocognition has on functioning. These three constructs and the related mediation effect may characterize different psychiatric syndromes other than PSDs. Structural equation modelling (SEM) was applied to baseline data from a longitudinal study of 138 young individuals with a recent-onset psychiatric disorder. Using SEM, we tested the hypothesis that ToM mediates the effect of neurocognition on functioning independent of the level of psychosis risk and the diagnostic category. In the mediation model the bootstrapping estimate revealed a significant indirect effect that was the association of social cognition with neurocognition and with functional outcome. ToM was significantly associated with neurocognition and the path from neurocognition to functioning was no longer significant as soon as the mediator (ToM) was entered into the mediation model consistent with a complete mediation effect through ToM. This mediation was independent of the psychosis-risk status and the psychiatric diagnoses. Our results provide useful information on a young psychiatric sample, in which specific therapeutic interventions have the potential to significantly limit functional disability. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Yamasaki, Syudo; Ando, Shuntaro; Koike, Shinsuke; Usami, Satoshi; Endo, Kaori; French, Paul; Sasaki, Tsukasa; Furukawa, Toshi A; Hasegawa-Hiraiwa, Mariko; Kasai, Kiyoto; Nishida, Atsushi
2016-06-01
Peer victimization increases the risk of experiencing psychotic symptoms among clinical and general populations, but the mechanism underlying this association remains unclear. Dissociation, which is related to peer victimization and hallucinatory experiences, has been demonstrated as a significant mediator in the relation between childhood victimization and hallucinatory experience among adult patients with psychosis. However, no studies have examined the mediating effect of dissociation in a general early adolescent population. We examined whether dissociation mediates the relationship between peer victimization and hallucinatory experiences among 10-year-old adolescents using a population-based cross-sectional survey of early adolescents and their main parent (Tokyo Early Adolescence Survey; N = 4478). We examined the mediating effect of dissociation, as well as external locus of control and depressive symptoms, on the relationship between peer victimization and hallucinatory experiences using path analysis. The model assuming mediation effects indicated good model fit (comparative fit index = .999; root mean square error of approximation = .015). The mediation effect between peer victimization and hallucination via dissociation (standardized indirect effect = .038, p < .001) was statistically significant, whereas the mediation effects of depressive symptoms (standardized indirect effect = -.0066, p = 0.318) and external locus of control (standardized indirect effect = .0024, p = 0.321) were not significant. These results suggest that dissociation is a mediator in the relation between peer victimization and hallucinatory experiences in early adolescence. For appropriate intervention strategies, assessing dissociation and peer victimization as they affect hallucinatory experiences is necessary.
Kim, Ji Young; Lee, Kyunghee
2015-10-01
The purpose of this study was to examine the moderating mediation effect of self-esteem on the relations among adolescents' abuse experiences, depression and anxiety, and suicidal ideation. The participants were selected using secondary data from a population in the 2012 Korea Welfare Panel Survey (KOWEPS). Data were analyzed using SPSS 15.0 and SPSS Macro, and bootstrapping and hierarchical regression analysis were performed to analyze multilevel models. First, analysis of the mediating effect of the adolescents' abuse showed that there was significant mediating influence between suicidal ideation and depression and anxiety. Second, hierarchical regression analysis showed that self-esteem had significant mediation effect on depression and anxiety in adolescents' suicidal ideation. Third, SPSS Macro showed that self-esteem also significantly moderated the mediating effect of adolescents' abuse experiences on suicidal ideation through depression and anxiety. The study results suggest that in future research on adolescent's abuse experience, the risk of suicide in depression and anxiety scores should be selected through evaluation of each individual's self-esteem scale. Coping strategies with immediate early intervention should be suggested.
Mediators of the effects on fatigue of pragmatic rehabilitation for chronic fatigue syndrome.
Wearden, Alison J; Emsley, Richard
2013-10-01
To examine potential mediators of the effect of pragmatic rehabilitation on improvements in fatigue following a randomized controlled trial for patients with chronic fatigue syndrome (CFS/ME) in primary care (IRCTN 74156610). Patients fulfilled the Oxford criteria for CFS. Ninety-five patients were randomized to pragmatic rehabilitation and 100 to general practitioner (GP) treatment as usual. The outcome was the Chalder fatigue scale score (0123 scoring) at end of treatment (20 weeks) and 1-year follow up (70 weeks). First, the effect of treatment on potential mediators was assessed. Then fatigue was regressed on significant mediators, treatment allocation, and baseline measures of fatigue and significant mediators. Reduction in limiting activities at 20 weeks mediated the positive effect of pragmatic rehabilitation on fatigue at 70 weeks (mediated effect size = -2.64, SE = 0.81, p = .001, proportion of effect mediated = 82.0%). Reduction in catastrophizing at 20 weeks mediated the positive effect of pragmatic rehabilitation on fatigue at 70 weeks (mediated effect size = -1.39, SE = 0.61, p = .023, proportion of effect mediated = 43.2%). Reductions in 70-week measures of fear avoidance, embarrassment avoidance, limiting activities, and all-or-nothing behavior all mediated improvement in fatigue at 70 weeks, although the causal direction of these cross-sectional effects cannot be determined. There were no between-group differences on measures of exercise capacity (a timed step test). Improvements in fatigue following pragmatic rehabilitation are related to changes in behavioral responses to and beliefs about fatigue.
Fitzsimmons-Craft, Ellen E; Bardone-Cone, Anna M; Crosby, Ross D; Engel, Scott G; Wonderlich, Stephen A; Bulik, Cynthia M
2016-09-01
Social comparisons (i.e., body, eating, exercise) and body surveillance were tested as mediators of the thin-ideal internalization-body dissatisfaction relationship using ecological momentary assessment (EMA). Participants were 232 college women who completed a 2-week EMA protocol, responding to questions three times per day. Multilevel path analysis was used to examine a 2-1-1 mediation model (thin-ideal internalization assessed as trait; between-person effects examined) and a 1-1-1 model (component of thin-ideal internalization [thin-ideal importance] assessed momentarily; within- and between-person effects examined). For the 2-1-1 model, only body comparison and body surveillance were significant specific mediators of the between-person effect. For the 1-1-1 model, all four variables were significant specific mediators of the within-person effect. Only body comparison was a significant specific mediator of the between-person effect. At the state level, many processes explain the thin-ideal internalization-body dissatisfaction relationship. However, at the trait level, body comparison and body surveillance are more important explanatory factors. Copyright © 2016 Elsevier Ltd. All rights reserved.
Fitzsimmons-Craft, Ellen E.; Bardone-Cone, Anna M.; Crosby, Ross D.; Engel, Scott G.; Wonderlich, Stephen A.; Bulik, Cynthia M.
2016-01-01
Social comparisons (i.e., body, eating, exercise) and body surveillance were tested as mediators of the thin-ideal internalization-body dissatisfaction relationship using ecological momentary assessment (EMA). Participants were 232 college women who completed a 2-week EMA protocol, responding to questions three times per day. Multilevel path analysis was used to examine a 2-1-1 mediation model (thin-ideal internalization assessed as trait; between-person effects examined) and a 1-1-1 model (component of thin-ideal internalization [thin-ideal importance] assessed momentarily; within- and between-person effects examined). For the 2-1-1 model, only body comparison and body surveillance were significant specific mediators of the between-person effect. For the 1-1-1 model, all four variables were significant specific mediators of the within-person effect. Only body comparison was a significant specific mediator of the between-person effect. At the state level, many processes explain the thin-ideal internalization-body dissatisfaction relationship. However, at the trait level, body comparison and body surveillance are more important explanatory factors. PMID:27391791
Roos, Corey R; Maisto, Stephen A; Witkiewitz, Katie
2017-09-01
There is inconsistent evidence that alcohol-specific coping is a mechanism of change in cognitive-behavioral therapy (CBT) for alcohol use disorder (AUD). Our primary aim was to test whether baseline dependence severity moderates the mediational effect of CBT on drinking outcomes via coping. Secondary data analysis of Project MATCH , a multi-site alcohol treatment trial in which participants, recruited in out-patient and aftercare arms, were randomized to three treatments: CBT, motivational enhancement therapy (MET) and Twelve-Step facilitation (TSF). Nine research sites in the United States. A total of 1063 adults with AUD. The primary outcomes were percentage days abstinent and percentage heavy drinking days at the 1-year follow-up. Coping was assessed with the Processes of Change Questionnaire . Dependence severity was measured with the Alcohol Dependence Scale . Among the full available sample (across treatment arms), there were no significant moderated mediation effects. Double moderated mediation analyses indicated that several moderated mediation effects were moderated by treatment arm (all P < 0.05). In the out-patient arm, there were several significant moderated mediation effects (all P < 0.05), but no significant moderated mediation effects in the aftercare arm. For out-patient clients with high baseline dependence severity, end-of-treatment coping mediated the positive treatment effects of CBT, compared with both MET and TSF, on 1-year drinking outcomes (all P < 0.05). Coping did not mediate treatment effects of CBT among those with low or moderate dependence severity. In the Project MATCH out-patient sample, whether or not coping mediated the effects of cognitive-behavioral therapy for alcohol use disorder was conditional on dependence severity. End-of-treatment coping mediated the positive treatment effects of cognitive-behavioral therapy on 1-year drinking outcomes among out-patient clients when dependence severity was high, but not when dependence severity was low or moderate. © 2017 Society for the Study of Addiction.
Depression and pain: testing of serial multiple mediators.
Wongpakaran, Tinakon; Wongpakaran, Nahathai; Tanchakvaranont, Sitthinant; Bookkamana, Putipong; Pinyopornpanish, Manee; Wannarit, Kamonporn; Satthapisit, Sirina; Nakawiro, Daochompu; Hiranyatheb, Thanita; Thongpibul, Kulvadee
2016-01-01
Despite the fact that pain is related to depression, few studies have been conducted to investigate the variables that mediate between the two conditions. In this study, the authors explored the following mediators: cognitive function, self-sacrificing interpersonal problems, and perception of stress, and the effects they had on pain symptoms among patients with depressive disorders. An analysis was performed on the data of 346 participants with unipolar depressive disorders. The 17-item Hamilton Depression Rating Scale, Mini-Mental State Examination, the pain subscale of the health-related quality of life (SF-36), the self-sacrificing subscale of the Inventory of Interpersonal Problems, and the Perceived Stress Scale were used. Parallel multiple mediator and serial multiple mediator models were used. An alternative model regarding the effect of self-sacrificing on pain was also proposed. Perceived stress, self-sacrificing interpersonal style, and cognitive function were found to significantly mediate the relationship between depression and pain, while controlling for demographic variables. The total effect of depression on pain was significant. This model, with an additional three mediators, accounted for 15% of the explained variance in pain compared to 9% without mediators. For the alternative model, after controlling for the mediators, a nonsignificant total direct effect level of self-sacrificing was found, suggesting that the effect of self-sacrificing on pain was based only on an indirect effect and that perceived stress was found to be the strongest mediator. Serial mediation may help us to see how depression and pain are linked and what the fundamental mediators are in the chain. No significant, indirect effect of self-sacrificing on pain was observed, if perceived stress was not part of the depression and/or cognitive function mediational chain. The results shown here have implications for future research, both in terms of testing the model and in clinical application.
Crangle, Cassandra J; Hart, Tae L
2017-11-01
Couples facing multiple sclerosis (MS) report significantly elevated rates of relationship distress, yet the effects of attachment have never been examined in this population. We examined whether hostile conflict mediated the dyadic effects of attachment on relationship adjustment in couples facing MS and whether these associations were moderated by gender or role. We also explored whether dyadic adjustment mediated the relationship between attachment and hostile conflict. The study was cross-sectional and included 103 couples in which one partner had been diagnosed with MS. Participants completed the Experiences in Close Relationships-Revised, Dyadic Adjustment Scale, and Aversive Interactions Scale, as well as demographic variables. We used the actor-partner interdependence model for data analysis. There were significant actor and partner effects of greater anxious attachment and worse dyadic adjustment. Actor and partner effects of anxious attachment were significantly mediated by greater hostile conflict. Gender significantly moderated the effects between avoidant attachment and dyadic adjustment. The actor effect was significant for males and females; the partner effect was only significant for females. The actor effect for females but not males was significantly mediated by greater hostile conflict. Role was not a significant moderator. Exploratory analyses also showed that dyadic adjustment mediated the relationship between anxious and avoidant attachment and hostile conflict. Findings highlight the important effects of attachment on relationship adjustment in MS couples. Both hostile conflict and dyadic adjustment appear to be mechanisms through which insecure attachment has a detrimental effect. Statement of contribution What is already known on this subject? Despite higher-than-normal rates of marital distress and separation/divorce, the effects of attachment on relationship adjustment among couples facing multiple sclerosis have never been examined. Prior studies within healthy populations have supported within-person and cross-dyadic associations between attachment and relationship adjustment; however, they have failed to use dyadic analyses. Hostile conflict has been associated with both insecure attachment and relationship adjustment and therefore may be an important mediator to help understand these relationships. What does this study add? Women were more negatively affected by their partner's avoidant attachment then men. Hostile conflict mediated the effects of anxious attachment on dyadic adjustment for individuals and across dyads. Hostile conflict accounted for the individual effect of avoidant attachment on dyadic adjustment for women. © 2017 The British Psychological Society.
Determinants of lifestyle behavior change to prevent type 2 diabetes in high-risk individuals.
den Braver, N R; de Vet, E; Duijzer, G; Ter Beek, J; Jansen, S C; Hiddink, G J; Feskens, E J M; Haveman-Nies, A
2017-06-12
Although there are many effective lifestyle interventions for type 2 diabetes (T2DM) prevention, insight into effective intervention pathways, especially of long-term interventions, is often lacking. This study aims to provide insight into the effective intervention pathways of the SLIMMER diabetes prevention intervention using mediation analyses. In total, 240 participants at increased risk of T2DM were included in the analyses over 18 months. The intervention was a combined lifestyle intervention with a dietary and a physical activity (PA) component. The primary and secondary outcomes were change in fasting insulin (pmol/L) and change in body weight (kg) after 18 months, respectively. Firstly, in a multiple mediator model, we investigated whether significant changes in these outcomes were mediated by changes in dietary and PA behavior. Secondly, in multiple single mediator models, we investigated whether changes in dietary and PA behavior were mediated by changes in behavioral determinants and the participants' psychological profile. The mediation analyses used linear regression models, where significance of indirect effects was calculated with bootstrapping. The effect of the intervention on decreased fasting insulin was 40% mediated by change in dietary and PA behavior, where dietary behavior was an independent mediator of the association (34%). The effect of the intervention on decreased body weight was 20% mediated by change in dietary and PA behavior, where PA behavior was an independent mediator (17%). The intervention significantly changed intake of fruit, fat from bread spread, and fiber from bread. Change in fruit intake was mediated by change in action control (combination of consciousness, self-control, and effort), motivation, self-efficacy, intention, and skills. Change in fat intake was mediated by change in action control and psychological profile. No mediators could be identified for change in fiber intake. The change in PA behavior was mediated by change in action control, motivation, and psychological profile. The effect of the SLIMMER intervention on fasting insulin and body weight was mediated by changes in dietary and PA behavior, in distinct ways. These results indicate that changing dietary as well as PA behavior is important in T2DM prevention.
Overweight, body image, and depression in Asian and Hispanic adolescents.
Xie, Bin; Unger, Jennifer B; Gallaher, Peggy; Johnson, C Anderson; Wu, Qiaobing; Chou, Chih-Ping
2010-01-01
To prospectively investigate associations between overweight and depressive symptoms in Asian and Hispanic adolescents. Data included 780 Hispanic and 375 Asian students. Structural equation model was used to prospectively explore moderation effects of gender, ethnicity, and acculturation on associations of overweight, body image dissatisfaction, and depressive symptoms. Significant mediation effect was found only in Asian girls (mediation effect = 0.16, P < 0.05) and girls with high acculturation (mediation effect = 0.17, P < 0.05). Overweight significantly predicted higher body image dissatisfaction, which in turn was significantly related to depressive symptoms. Our findings help understanding the association of overweight and experience of depressive symptoms.
Neuroticism and quality of life: Multiple mediating effects of smartphone addiction and depression.
Gao, Tingting; Xiang, Yu-Tao; Zhang, Han; Zhang, Zhao; Mei, Songli
2017-12-01
The purposes of this study were to investigate the mediating effect of smartphone addiction and depression on neuroticism and quality of life. Self-reported measures of neuroticism, smart-phone addiction, depression, and quality of life were administered to 722 Chinese university students. Results showed smartphone addiction and depression were both significantly affected neuroticism and quality of life. The direct effect of neuroticism on quality of life was significant, and the chain-mediating effect of smartphone addiction and depression was also significant. In conclusion, neuroticism, smartphone addiction, and depression are important variables that worsen quality of life. Copyright © 2017 Elsevier B.V. All rights reserved.
Zhang, Huijie; Zhang, Tao; Li, Shengxu; Guo, Yajun; Shen, Wei; Fernandez, Camilo; Harville, Emily; Bazzano, Lydia A; Urbina, Elaine M; He, Jiang; Chen, Wei
2017-05-12
Childhood adiposity is associated with cardiac structure in later life, but little is known regarding to what extent childhood body weight affects adult left ventricular geometric patterns through adult body size and blood pressure (BP). Determine quantitatively the mediation effect of adult body weight and BP on the association of childhood body mass index (BMI) with adult left ventricular (LV) hypertrophy. This longitudinal study consisted of 710 adults, aged 26 to 48 years, who had been examined for BMI and BP measured ≥4× during childhood and ≥2× during adulthood, with a mean follow-up period of 28.0 years. After adjusting for age, race, and sex, adult BMI had a significant mediation effect (76.4%; P <0.01) on the childhood BMI-adult LV mass index association. The mediation effects of adult systolic BP (15.2%), long-term burden (12.1%), and increasing trends of systolic BP (7.9%) were all significant ( P <0.01). Furthermore, these mediators also had significant mediation effects on the association of childhood BMI with adult LV hypertrophy, eccentric hypertrophy, and concentric hypertrophy. Importantly, the mediation effects of adult BMI were all significantly stronger than those of adult systolic BP on LV mass index, LV hypertrophy, and LV remodeling patterns ( P <0.01). Additionally, the mediation effect of systolic BP on concentric hypertrophy was significantly stronger than that on eccentric hypertrophy ( P <0.01). These findings suggest that increased childhood BMI has long-term adverse impact on subclinical changes in adult cardiac structure, and early life excessive body weight and adult LV hypertrophy are linked through later life excessive body weight and elevated BP. © 2017 American Heart Association, Inc.
Parental mediation and cyberbullying - a longitudinal study.
Chng, Grace S; Liau, Albert; Khoo, Angeline; Li, Dongdong
2014-01-01
Parents use active and restrictive mediation strategies to guide and regulate children's online participation and the online risks they encounter. However, changes in parental mediation do occur over time and the effectiveness of these strategies on cyberbullying demands for further empirical investigation. The current study addresses these issues with a sample of 1084 students (49% girls) in a longitudinal, three-wave design. Gender differences were tested via multi-group analyses. Longitudinal growth models showed that parental use of both active and restrictive mediation decreased over time. For both types of mediation, the mean rate of change had a significant effect on boys' engagement in cyberbullying, but not for girls. Initial levels of restrictive mediation, but not active mediation, were found to be significantly predictive of cyberbullying in both genders. Girls had higher initial levels of both parental mediation types in comparison to boys. The results reveal that the effectiveness of active and restrictive mediation in relation to students' cyberbullying differs and informs us on gender differences. The implications of these results for parental education in online mediation are discussed.
Yoo, Jieun
2017-12-01
The present study examined the relationship between two categories of religious involvement, namely religious belief and religious behavior, and life satisfaction among Korean Christians (N = 278) with spiritual well-being and self-esteem as potential mediators in this relationship by using structural equation modeling (SEM). The results supported the full mediated structural model and indicated that religious belief had a significant indirect effect on life satisfaction through the mediators, spiritual well-being and self-esteem. Religious behavior did not have an indirect or direct effect on life satisfaction among Korean Christians. The significance, implications, and limitations of the study were discussed.
Lee, Hyung Tak; Park, Jin-Kyu; Choi, Sung Yong; Choi, Bo Youl; Kim, Mi Kyung; Mori, Mari; Yamori, Yukio; Lim, Young Hyo; Shin, Jinho
2016-01-01
The aim of this study was to evaluate the mediating effects of nocturnal blood pressure (BP) and morning surge on the contribution of arterial stiffness and sodium intake to morning BP in a middle-aged general population. The study included 124 subjects aged 30-59 years, from rural Yeoju County, Gyeonggi Province, South Korea. Ambulatory BP monitoring, 24 h urinary sodium excretion (24 h UNa) and brachial-ankle pulse wave velocity (baPWV) measurements were performed in all subjects. The mean ± SD age was 48.1 ± 8.2 years and the proportion of male subjects was 41.1%. After adjusting for covariates, morning systolic blood pressure (SBP) was significantly correlated with morning surge [coefficient = 0.761, 95% confidence interval (CI) 0.651-0.872, p < 0.001], nocturnal SBP (coefficient = 0.576, 95% CI 0.454-0.698, p < 0.001) and baPWV (coefficient = 3.550, 95% CI 1.447-5.653, p = 0.001). Path analysis modeling revealed that baPWV had significant direct (0.035, p = 0.013) and indirect effects (0.042, p = 0.012) on morning SBP. The indirect effect mediated by nocturnal SBP was statistically significant (0.054, p = 0.005), but the indirect effect mediated by the morning surge was not significant. The 24 h UNa had no significant direct or indirect effects on morning SBP. baPWV had significant direct and indirect effects on morning SBP. The indirect effect was mediated by nocturnal SBP, but not by morning surge. The 24 h UNa had neither significant direct nor indirect effects on morning SBP.
Yamada, Ann-Marie; Lee, Karen K; Dinh, Tam Q; Barrio, Concepción; Brekke, John S
2010-01-01
This study investigated intrinsic motivation as a mediator of the relationship between clinical symptoms and functioning. The mediation model was tested with a sample of 166 adults with schizophrenia spectrum disorders attending psychosocial rehabilitation programs in a diverse urban community. Ethnic minority status was examined as a moderator of the mediation model. Motivation was measured using items reflecting intrapsychic drive. Symptoms were assessed with the expanded Brief Psychiatric Rating Scale and functioning with the Role Functioning Scale. Motivation was a significant mediator of the relationship between functioning and all symptom scores; fully mediating the relationship between functioning and negative, disorganized, and global symptoms, and partially mediating the relationship between positive symptoms and functioning. Motivation scores between ethnic minority and nonminority individuals differed significantly (p < 0.05), but no moderation effect was indicated. The strong mediation effect schizophrenia of motivation on the symptoms-functioning relationship supports future work to translate findings into effective recovery-oriented services.
Yamada, Ann-Marie; Lee, Karen K.; Dinh, Tam Q.; Barrio, Concepción; Brekke, John S.
2010-01-01
This study investigated intrinsic motivation as a mediator of the relationship between clinical symptoms and functioning. The mediation model was tested with a sample of 166 adults with schizophrenia spectrum disorders attending psychosocial rehabilitation programs in a diverse urban community. Ethnic minority status was examined as a moderator of the mediation model. Motivation was measured using items reflecting intrapsychic drive. Symptoms were assessed with the expanded Brief Psychiatric Rating Scale and functioning with the Role Functioning Scale. Motivation was a significant mediator of the relationship between functioning and all symptom scores; fully mediating the relationship between functioning and negative, disorganized, and global symptoms, and partially mediating the relationship between positive symptoms and functioning. Motivation scores between ethnic minority and nonminority individuals differed significantly (p < 0.05), but no moderation effect was indicated. The strong mediation effect schizophrenia of motivation on the symptoms-functioning relationship supports future work to translate findings into effective recovery-oriented services. PMID:20061866
Menatti, Andrew R.; Weeks, Justin W.; Levinson, Cheri A.; McGowan, Maggie M.
2013-01-01
Previous findings indicate that social anxiety and bulimia co-occur at high rates; one mechanism that has been proposed to link these symptom clusters is perfectionism. We tested meditational models among 167 female undergraduates in which maladaptive evaluative perfectionism concerns (MEPC; i.e., critical self-evaluative perfectionism) mediated the relationship between social anxiety and bulimic symptoms. Results from a first model indicated that MEPC mediated the relationship between fear of public scrutiny and bulimia symptoms. This indirect effect was significant above and beyond the indirect effects of maladaptive body-image cognitions and perfectionism specific to pure personal standards. A second model was tested with MEPC mediating the relationship between social interaction anxiety and bulimia symptoms. Similar results were obtained; however, in this model, a significant direct effect remained after partialing out the indirect effect of the mediators. Theoretical implications are discussed. PMID:24932054
Cohen, Lisa; Leibu, Olga; Tanis, Thachell; Ardalan, Firouz; Galynker, Igor
2016-07-01
Despite a robust literature documenting the relationship between childhood maltreatment and personality pathology in adulthood, there is far less clarity about the mechanism underlying this relationship. One promising candidate for such a linking mechanism is disturbance in the sense of self. This paper tests the hypothesis that disturbances in the sense of self mediate the relationship between childhood maltreatment and adult personality pathology. Specifically, we assess the self-related traits of stable self-image, self-reflective functioning, self-respect and feeling recognized. The sample included 113 non-psychotic psychiatric inpatients. Participants completed the Child Trauma Questionnaire (CTQ), the Personality Diagnostic Questionnaire-4 (PDQ-4+), and the self-reflexive functioning, stable self image, self-respect, and feeling recognized scales from the Severity Indices of Personality Problems (SIPP-118). A series of linear regressions was then performed to assess the direct and indirect effects of childhood trauma on personality disorder traits (PDQ-4+ total score), as mediated by self concept (SIPP-118 scales). Aroian tests assessed the statistical significance of each mediating effect. There was a significant mediating effect for all SIPP self concept variables, with a full mediating effect for the SIPP composite score and for SIPP feeling recognized and self-reflexive functioning, such that the direct effect of childhood trauma on personality did not retain significance after accounting for the effect of these variables. There was a partial mediating effect for SIPP stable self image and self-respect, such that the direct effect of the CTQ retained significance after accounting for these variables. SIPP feeling recognized had the strongest mediating effect. Multiple facets of self concept, particularly the degree to which an individual feels understood by other people, may mediate the relationship between childhood maltreatment and adult personality pathology. This underscores the importance of attending to disturbances in the sense of self in patients with personality pathology and a history of childhood maltreatment. These findings also support the centrality of disturbed self concept to the general construct of personality pathology. Copyright © 2016. Published by Elsevier Inc.
Overweight, Body Image, and Depression in Asian and Hispanic Adolescents
Xie, Bin; Unger, Jennifer B.; Gallaher, Peggy; Johnson, C. Anderson; Wu, Qiaobing; Chou, Chih-Ping
2010-01-01
Objectives To prospectively investigate associations between overweight and depressive symptoms in Asian and Hispanic adolescents. Methods Data included 780 Hispanic and 375 Asian students. Structural equation model was used to prospectively explore moderation effects of gender, ethnicity, and acculturation on associations of overweight, body image dissatisfaction, and depressive symptoms. Results Significant mediation effect was found only in Asian girls (mediation effect=0.16, P<0.05) and girls with high acculturation (mediation effect=0.17, P<0.05). Overweight significantly predicted higher body image dissatisfaction, which in turn was significantly related to depressive symptoms. Conclusion Our findings help understanding the association of overweight and experience of depressive symptoms. PMID:20218759
Parental modeling, education and children's sports and TV time: the ENERGY-project.
Fernández-Alvira, Juan M; Te Velde, Saskia J; Singh, Amika; Jiménez-Pavón, David; De Bourdeaudhuij, Ilse; Bere, Elling; Manios, Yannis; Kovacs, Eva; Jan, Nataša; Moreno, Luis A; Brug, Johannes
2015-01-01
We assessed whether differences in children's sports participation and television time according to parental education were mediated by parental modeling. Moreover, we explored the differences between parental and child reports on parental sports participation and television time as potential mediators. 5729 children and 5183 parents participating in the EuropeaN Energy balance Research to prevent excessive weight Gain among Youth (ENERGY-project) during 2010 in seven European countries provided information on sports participation and television time using validated self-report questionnaires. Multilevel country-specific mediation models analyzed the potential mediation effect of parental self-reports and child-reports on parental sports participation and television time. Significant mediation effect was found for parental self-reported television time in four countries (Greece, Hungary, The Netherlands and Slovenia), with the highest proportion for Slovenia (40%) and the lowest for Greece (21%). Child-reported parental television time showed mediation effect in Greece only. Parental self-reported sports participation showed significant mediation effect only in Greece. With child-reported parental sports participation, significant mediation was observed in Greece and Norway. Parental behaviors appear to be important in explaining parental educational differences in children's sports participation and television time. However, child reports on parental behavior appear to be more relevant than parents' self-reports as correlates of children's own sports participation and television time. Copyright © 2014 Elsevier Inc. All rights reserved.
Bushmakin, A G; Cappelleri, J C; Symonds, T; Stecher, V J
2014-01-01
To apportion the direct effect and the indirect effect (through erections) that sildenafil (vs placebo) has on individual satisfaction and couple satisfaction over time, longitudinal mediation modeling was applied to outcomes on the Sexual Experience Questionnaire. The model included data from weeks 4 and 10 (double-blind phase) and week 16 (open-label phase) of a controlled study. Data from 167 patients with erectile dysfunction (ED) were available for analysis. Estimation of statistical significance was based on bootstrap simulations, which allowed inferences at and between time points. Percentages (and corresponding 95% confidence intervals) for direct and indirect effects of treatment were calculated using the model. For the individual satisfaction and couple satisfaction domains, direct treatment effects were negligible (not statistically significant) whereas indirect treatment effects via the erection domain represented >90% of the treatment effects (statistically significant). Week 4 vs week 10 percentages of direct and indirect effects were not statistically different, indicating that the mediation effects are longitudinally invariant. As there was no placebo arm in the open-label phase, mediation effects at week 16 were not estimable. In conclusion, erection has a crucial role as a mediator in restoring individual satisfaction and couple satisfaction in men with ED treated with sildenafil.
Wei, Meifen; Li, Chun-I; Wang, Cixin; Ko, Stacy Y
2016-11-01
This study examined a moderated mediation model to see whether self-reflection moderated (a) the association between acculturative stress and ethnocultural empathy and (b) the indirect effects of acculturative stress on 2 positive outcomes (i.e., bicultural competence and making positive sense of adversity) through ethnocultural empathy. A total of 330 Asian American college students from a West coast university participated in an online survey. Results from PROCESS supported hypotheses. First, self-reflection significantly moderated the effects of acculturative stress on ethnocultural empathy. Specifically, the effect of acculturative stress on ethnocultural empathy was significantly positive for those with lower self-reflection. Conversely, this effect was not significant for those with higher self-reflection, but ethnocultural empathy was consistently high across all levels of acculturative stress for those with higher self-reflection. Post hoc exploratory analyses examined the moderated mediation model using each of the 5 domains of acculturative stress as predictors; results supported the moderated mediation hypotheses for 2 domains, discrimination and cultural isolation. Second, self-reflection significantly moderated the indirect effects of acculturative stress on 2 positive outcomes through ethnocultural empathy. Results from conditional indirect effects suggested that the indirect effects of acculturative stress on 2 positive outcomes through ethnocultural empathy were significantly positive for those with lower self-reflection. Conversely, the indirect effects were not significant for those with higher self-reflection, but the 2 positive outcomes stayed high at all levels of acculturative stress. Post hoc analyses found that 5 of 6 components of bicultural competence used as outcome variables supported the moderation mediation hypotheses. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
ERIC Educational Resources Information Center
Leth-Steensen, Craig; Gallitto, Elena
2016-01-01
A large number of approaches have been proposed for estimating and testing the significance of indirect effects in mediation models. In this study, four sets of Monte Carlo simulations involving full latent variable structural equation models were run in order to contrast the effectiveness of the currently popular bias-corrected bootstrapping…
Peer Support and Adolescents' Physical Activity: The Mediating Roles of Self-Efficacy and Enjoyment.
Chen, Han; Sun, Haichun; Dai, Jun
2017-06-01
The present study aimed to contrast the mediating magnitude of self-efficacy and enjoyment connecting peer support and adolescents' physical activity (PA). Participants were 9th-12th grade students ( N = 409; 56.5% boys) who were randomly chosen from six public schools located in Fuzhou city in southeast China. The bootstrapping method in structural equation modeling was conducted to examine the direct and indirect effects of peer support on adolescents' PA. Peer support did not directly impact PA. Rather, peer support indirectly influenced PA through either self-efficacy or enjoyment, with self-efficacy demonstrating a stronger mediating effect. Additionally, we found a significant serial mediating effect with enjoyment, and self-efficacy sequentially mediated the relationship between peer support and PA. The findings highlight the role of self-efficacy and enjoyment as mediators connecting peer support and PA. Self-efficacy seems to be more important, as it demonstrated a significantly greater mediating effect. © The Author 2017. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com
Patient Expectancy as a Mediator of Placebo Effects in Antidepressant Clinical Trials.
Rutherford, Bret R; Wall, Melanie M; Brown, Patrick J; Choo, Tse-Hwei; Wager, Tor D; Peterson, Bradley S; Chung, Sarah; Kirsch, Irving; Roose, Steven P
2017-02-01
Causes of placebo effects in antidepressant trials have been inferred from observational studies and meta-analyses, but their mechanisms have not been directly established. The goal of this study was to examine in a prospective, randomized controlled trial whether patient expectancy mediates placebo effects in antidepressant studies. Adult outpatients with major depressive disorder were randomly assigned to open or placebo-controlled citalopram treatment. Following measurement of pre- and postrandomization expectancy, participants were treated with citalopram or placebo for 8 weeks. Independent samples t tests determined whether patient expectancy differed between the open and placebo-controlled groups, and mixed-effects models assessed group effects on Hamilton Depression Rating Scale (HAM-D) scores over time while controlling for treatment assignment. Finally, mediation analyses tested whether between-group differences in patient expectancy mediated the group effect on HAM-D scores. Postrandomization expectancy scores were significantly higher in the open group (mean=12.1 [SD=2.1]) compared with the placebo-controlled group (mean=11.0 [SD=2.0]). Mixed-effects modeling revealed a significant week-by-group interaction, indicating that HAM-D scores for citalopram-treated participants declined at a faster rate in the open group compared with the placebo-controlled group. Patient expectations postrandomization partially mediated group effects on week 8 HAM-D. Patient expectancy is a significant mediator of placebo effects in antidepressant trials. Expectancy-related interventions should be investigated as a means of controlling placebo responses in antidepressant clinical trials and improving patient outcome in clinical treatment.
Chang, Feng-Hang; Latham, Nancy K; Ni, Pengsheng; Jette, Alan M
2015-06-01
To examine whether self-efficacy mediated the effect of the Home-based Post-Hip Fracture Rehabilitation program on activity limitations in older adults after hip fracture and whether the mediating effect was different between sex and age groups. Randomized controlled trial. Community. Participants with hip fracture (N=232; mean age ± SD, 79±9.4y) were randomly assigned to intervention (n=120, 51.7%) and attention control (n=112, 48.3%) groups. The 6-month intervention, the Home-based Post-Hip Fracture Rehabilitation, is a functionally oriented, home-based exercise program. Data were collected at baseline, postintervention (6mo), and follow-up (9mo). Activity Measure for Post-Acute Care. The mediating effect of the Home-based Post-Hip Fracture Rehabilitation program on Basic Mobility function through self-efficacy for exercise was significant at 9 months (βindirect=.21). Similarly, the mediating effect of the intervention on Daily Activity function through self-efficacy for exercise was significant at 9 months (βindirect=.49). In subgroup analyses, the mediating effect was significant at 9 months in the younger group (age, ≤79y) in comparison to the older group and was significant in women in comparison to men. Self-efficacy may play a partial mediating role in the effect on some longer-term functional outcomes in the Home-based Post-Hip Fracture Rehabilitation intervention. The results suggest that program components that target self-efficacy should be incorporated in future hip fracture rehabilitation interventions. Age and sex of the targeted participants may also need to be considered when developing interventions. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Latham, Nancy K.; Ni, Pengsheng; Jette, Alan M.
2015-01-01
Objectives This study examined whether self-efficacy mediated the effect of the HIP Rehab exercise program on activity limitations in older adults after hip fracture, and whether the mediation effect was different between different gender and age groups. Design Randomized controlled trial (RCT) Setting Community Participants Two hundred and thirty two participants aged 79±9.4 years with hip fracture were randomly assigned to intervention (n=120) or attention control (n=112) groups. Interventions The 6-month intervention, the HIP Rehab, is a functionally-oriented, home-based exercise program. Data was collected at baseline, post-intervention (6 months), and follow-up (9 months). Main outcome measure Activity Measure for Post-Acute Care (AM-PAC) Results The mediation effect of the HIP Rehab exercise program on Basic Mobility function through self-efficacy for exercise was significant at 9 months (βindirect=0.21). Similarly, the mediation effect of the intervention on Daily Activity function through self-efficacy for exercise was significant at 9 months (βindirect=0.49). In subgroup analyses, the mediation effect was significant at 9 months in the younger group (≤79 years old) in comparison to the older group, and was significant in females in comparison to males. Conclusion Self-efficacy may play a partial mediating role for the effect on some longer-term functional outcomes in the HIP Rehab intervention. The results suggest that program components that target self-efficacy should be incorporated in the future hip fracture rehabilitation interventions. Age and gender of the targeted participants may also need to be considered when developing interventions. PMID:25701101
Active video games: the mediating effect of aerobic fitness on body composition.
Maddison, Ralph; Mhurchu, Cliona Ni; Jull, Andrew; Prapavessis, Harry; Foley, Louise S; Jiang, Yannan
2012-05-03
Increased understanding of why and how physical activity impacts on health outcomes is needed to increase the effectiveness of physical activity interventions. A recent randomized controlled trial of an active video game (PlayStation EyeToy™) intervention showed a statistically significant treatment effect on the primary outcome, change from baseline in body mass index (BMI), which favored the intervention group at 24 weeks. In this short paper we evaluate the mediating effects of the secondary outcomes. To identify mediators of the effect of an active video games intervention on body composition. Data from a two-arm parallel randomized controlled trial of an active video game intervention (n = 322) were analyzed. The primary outcome was change from baseline in BMI. A priori secondary outcomes were considered as potential mediators of the intervention on BMI, including aerobic fitness (VO2Max), time spent in moderate-to-vigorous physical activity (MVPA), and food snacking at 24 weeks. Only aerobic fitness at 24 weeks met the conditions for mediation, and was a significant mediator of BMI. Playing active video games can have a positive effect on body composition in overweight or obese children and this effect is most likely mediated through improved aerobic fitness. Future trials should examine other potential mediators related to this type of intervention. Australian New Zealand Clinical Trials Registry Website: http://www.anzctr.org.au. Study ID number: ACTRN12607000632493.
Mediating Effects of Social Support on Firefighters' Sense of Community and Perceptions of Care
ERIC Educational Resources Information Center
Cowman, Shaun E.; Ferrari, Joseph R.; Liao-Troth, Matthew
2004-01-01
This study examined the relationship between psychological sense of community, social-support networks, and care-giver stress and satisfaction among firefighters. No significant gender differences were obtained, but zero-order correlates demonstrated significant relationships among all four variables. In examining the mediating effects of…
Yen, Cheng-Fang; Lin, I-Mei; Liu, Tai-Ling; Hu, Huei-Fan; Cheng, Chung-Ping
2014-08-01
This study aimed to examine the mediating effects of depression and anxiety on the relationships of bullying victimization and perpetration with pain among adolescents in Taiwan. A total of 4976 students of junior and senior high schools completed the questionnaires. Bullying victimization and perpetration, pain problems, depression, and anxiety were assessed. The mediating effects of depression and anxiety on the relationship between bullying involvement and pain problems and the moderating effects of sex on the medicating roles of depression and anxiety were examined by structural equation model. Both depression and anxiety were significant mediators of the relationship between bullying victimization and pain problems among adolescents. Depression was also a significant mediator of the relationship between bullying perpetration and pain problems among adolescents. Sex had no moderating effect on the mediating role of depression/anxiety on the association between bullying involvement and pain problems. Medical and educational professionals should survey and intervene in depression and anxiety when managing pain problems among adolescents involved in bullying. Copyright © 2014 Elsevier Inc. All rights reserved.
Yuma-Guerrero, Paula J; Cubbin, Catherine; von Sternberg, Kirk
2017-12-01
The purpose of this study was to determine if social cohesion mediates the effects of neighborhood and household-level socioeconomic status (SES), perceptions of neighborhood safety, and access to parks on mothers' engagement in physical activity (PA). Secondary analyses were conducted on cross-sectional data from The Geographic Research on Wellbeing (GROW) study. GROW includes survey data from a diverse sample of 2,750 California mothers. Structural equation modeling was used to test a conceptual multilevel mediation model, proposing social cohesion as a mediator of known predictors of PA. Social cohesion fully mediated the pathway from perceived neighborhood safety to mothers' PA. Social cohesion also mediated the significant relationship between neighborhood SES and PA; however, this mediation finding was not practically significant when considered in the context of the full model. Household SES was significantly positively related to both social cohesion and PA. Park access contributed significantly to social cohesion but not directly to PA Social cohesion did not significantly mediate relationships between park access or household SES and PA. There is a need for public health interventions to improve engagement in PA among individuals and neighborhoods with lower levels of socioeconomic resources. Interventions that create social cohesion within neighborhoods may have positive effects on mothers' PA, particularly in neighborhoods perceived as unsafe.
Smith, Jordan J; Morgan, Philip J; Plotnikoff, Ronald C; Stodden, David F; Lubans, David R
2016-01-01
The purpose of this study was to examine the mediating effect of resistance training skill competency on percentage of body fat, muscular fitness and physical activity among a sample of adolescent boys participating in a school-based obesity prevention intervention. Participants were 361 adolescent boys taking part in the Active Teen Leaders Avoiding Screen-time (ATLAS) cluster randomised controlled trial: a school-based program targeting the health behaviours of economically disadvantaged adolescent males considered "at-risk" of obesity. Body fat percentage (bioelectrical impedance), muscular fitness (hand grip dynamometry and push-ups), physical activity (accelerometry) and resistance training skill competency were assessed at baseline and post-intervention (i.e., 8 months). Three separate multi-level mediation models were analysed to investigate the potential mediating effects of resistance training skill competency on each of the study outcomes using a product-of-coefficients test. Analyses followed the intention-to-treat principle. The intervention had a significant impact on the resistance training skill competency of the boys, and improvements in skill competency significantly mediated the effect of the intervention on percentage of body fat and the combined muscular fitness score. No significant mediated effects were found for physical activity. Improving resistance training skill competency may be an effective strategy for achieving improvements in body composition and muscular fitness in adolescent boys.
Zhang, Liying; Li, Xiaoming; Lin, Zhenping; Jacques-Tiura, Angela J; Xu, Jinping; Zhou, Yuejiao; Qiao, Shan; Shen, Zhiyong; Stanton, Bonita
2016-07-01
Antiretroviral therapy (ART) is a lifelong treatment. To date, ART adherence is suboptimal for most patients in resource-poor settings. Previous research indicates that medication side effects are perceived to be a significant barrier of high ART adherence. Data regarding the role of adherence self-efficacy in mediating the relationship between side effects from ART and adherence to ART are limited; thus, this study examines this potential mediational role of self-efficacy. A cross-sectional survey of 2987 people living with HIV aged ≥18 years was conducted in 2012-2013 in Guangxi Autonomous Region (Guangxi) which has one of the fastest-growing HIV rates in China. Of the total sample, 2146 (72.1%) participants had initiated ART. Participants reported the number of days of completing the daily dose of ART in the past month; adherence was defined as completing the daily dose at least 28 days in the last month (≥90%). Side effects were significantly negatively related to adherence to ART. Mediation analyses indicated that adherence self-efficacy significantly mediated the side effects-adherence relationship. Future interventions to increase adherence self-efficacy and effective coping with side effects among HIV patients are needed in order to improve their ART adherence.
Reducing Levels of Elementary School Violence with Peer Mediation
ERIC Educational Resources Information Center
Schellenberg, Rita Cantrell; Parks-Savage, Agatha; Rehfuss, Mark
2007-01-01
The effectiveness of an existing peer mediation program in a diverse, suburban elementary school was examined. Peer mediation was available to all students (N = 825). Three-year longitudinal data showed significant reductions in the school's out-of-school suspensions after implementation of the peer mediation program. Mediation training also…
NASA Astrophysics Data System (ADS)
Ozyurek, Abdullah Selim
Many dynamics directly or indirectly influence the decision-making process. An individual's demographic features, such as gender, country of origin, and emotions are some of the dynamics. In the aviation domain, air passengers purchase their air travel tickets under those dynamics. The purpose of this study was to determine if the airline type, gender of participants, and participants' country of origin had an effect on ratings of an individual's perception of safety and willingness to fly, and which emotions had a mediating effect on this relationship. The study included Lufthansa Airlines and Turkish Airlines from Europe. The affect was the participants' feeling outcomes of presented airline information. The feelings were Ekman and Friesen's (1971) universal emotions that include happiness, surprise, fear, disgust, anger, and sadness. The results of the study indicated that airline type, gender, and country of origin had a statistically significant effect and significant interaction on safety perception and willingness to fly. Also, emotions were found significant mediators on the mediation paths. Particularly happiness, fear, anger, and disgust emotions had a significant influence on participants' decision outcomes.
[Mediating effect of mental elasticity on occupational stress and depression in female nurses].
Wang, Y W; Liu, G Z; Zhou, X T; Sheng, P J; Cui, F F; Shi, T
2017-06-20
Objective: To investigate the interaction between mental elasticityand occupational stress and depressionin female nurses and the mediating effect of mental elasticity, as well as the functioning way of mental elasticity in occupational stress-depression. Methods: From August to October, 2015, cluster sampling was used to select 122 female nurses in a county-level medical institution as study subjects. The Connor-Davidson Resilience Scale (CD-RISC) , Occupational Stress Inventory-Revised Edition (OSI-R) , and Self-Rating Depression Scale (SDS) were used to collect the data on mental elasticity, occupational stress, and depression and analyze their correlation and mediating effect. Results: The 122 female nurses had a mean mental elasticity score of 62.4±15.1, which was significantly lower than the Chinese norm (65.4±13.9) ( P <0.05) ; the mean depression score was 41.0±7.7, which was significantly higher than the Chinese norm (33.5±8.6) ( P <0.01) , and the incidence rate of depression of 52.5%. Mental elasticity was negatively correlated with occupational stress and depression ( r =-0.559 and -0.559, both P <0.01) . Occupational stress and the two subscales mental stress reaction and physical stress reaction were positively correlated with depression ( r =0.774, 0.734, and 0.725, all P <0.01) . After adjustment for confounding factors, occupational stress had a positive predictive effect on depression ( β =0.744, P <0.01) , and mental elasticity had a negative predictive effect on depression ( β =-0.221, P <0.01) . The analysis of mediating effect showed a significant direct effect of occupational stress on depression and a significant mediating effect of mental elasticity ( a =-0.527, b =-0.227, c =0.744, c '=0.627; all P <0.01) , and the mediating effect of mental elasticity accounted for 16.08% of the total effect. Conclusion: As a partial mediating variable, mental elasticity has an indirect effect on the relationship between occupational stress and depression and can alleviate the adverse effect of occupational stress and reduce the development of depression.
Ali, Arshad; Mattsson, Eskil
2017-11-15
The biodiversity - aboveground biomass relationship has been intensively studied in recent decades. However, no consensus has been arrived to consider the interplay of species diversity, and intraspecific and interspecific tree size variation in driving aboveground biomass, after accounting for the effects of plot size heterogeneity, soil fertility and stand quality in natural forest including agroforests. We tested the full, partial and no mediations effects of species diversity, and intraspecific and interspecific tree size variation on aboveground biomass by employing structural equation models (SEMs) using data from 45 homegarden agroforestry systems in Sri Lanka. The full mediation effect of either species diversity or intraspecific and interspecific tree size variation was rejected, while the partial and no mediation effects were accepted. In the no mediation SEM, homegarden size had the strongest negative direct effect (β=-0.49) on aboveground biomass (R 2 =0.65), followed by strong positive direct effect of intraspecific tree size variation (β=0.32), species diversity (β=0.29) and interspecific tree size variation (β=0.28). Soil fertility had a negative direct effect on interspecific tree size variation (β=-0.31). Stand quality had a significant positive total effect on aboveground biomass (β=0.28), but homegarden size had a significant negative total effect (β=-0.62), while soil fertility had a non-significant total effect on aboveground biomass. Similar to the no mediation SEM, the partial mediation SEMs had explained almost similar variation in aboveground biomass because species diversity, and intraspecific and interspecific tree size variation had non-significant indirect effects on aboveground biomass via each other. Our results strongly suggest that a multilayered tree canopy structure, due to high intraspecific and interspecific tree size variation, increases light capture and efficient utilization of resources among component species, and hence, support the niche complementarity mechanism via plant-plant interactions. Copyright © 2017 Elsevier B.V. All rights reserved.
Active video games: the mediating effect of aerobic fitness on body composition
2012-01-01
Background Increased understanding of why and how physical activity impacts on health outcomes is needed to increase the effectiveness of physical activity interventions. A recent randomized controlled trial of an active video game (PlayStation EyeToy™) intervention showed a statistically significant treatment effect on the primary outcome, change from baseline in body mass index (BMI), which favored the intervention group at 24 weeks. In this short paper we evaluate the mediating effects of the secondary outcomes. Objective To identify mediators of the effect of an active video games intervention on body composition. Methods Data from a two-arm parallel randomized controlled trial of an active video game intervention (n = 322) were analyzed. The primary outcome was change from baseline in BMI. A priori secondary outcomes were considered as potential mediators of the intervention on BMI, including aerobic fitness (VO2Max), time spent in moderate-to-vigorous physical activity (MVPA), and food snacking at 24 weeks. Results Only aerobic fitness at 24 weeks met the conditions for mediation, and was a significant mediator of BMI. Conclusion Playing active video games can have a positive effect on body composition in overweight or obese children and this effect is most likely mediated through improved aerobic fitness. Future trials should examine other potential mediators related to this type of intervention. Trial registration Australian New Zealand Clinical Trials Registry Website: http://www.anzctr.org.au Study ID number: ACTRN12607000632493 PMID:22554052
Interpreting instructional cues in task switching procedures: the role of mediator retrieval.
Logan, Gordon D; Schneider, Darryl W
2006-03-01
In 3 experiments the role of mediators in task switching with transparent and nontransparent cues was examined. Subjects switched between magnitude (greater or less than 5) and parity (odd or even) judgments of single digits. A cue-target congruency effect indicated mediator use: subjects responded faster to congruent cue-target combinations (e.g., ODD-3) than to incongruent cue-target combinations (e.g., ODD-4). Experiment 1 revealed significant congruency effects with transparent word cues (ODD, EVEN, HIGH, and LOW) and with relatively transparent letter cues (O, E, H, and L) but not with nontransparent letter cues (D, V, G, and W). Experiment 2 revealed significant congruency effects after subjects who were trained with nontransparent letter cues were informed of the relations between cues and word mediators halfway through the experiment. Experiment 3 showed that congruency effects with relatively transparent letter cues diminished over 10 sessions of practice, suggesting that subjects used mediators less as practice progressed. The results are discussed in terms of the role of mediators in interpreting instructional cues.
The applied model of imagery use: Examination of moderation and mediation effects.
Koehn, S; Stavrou, N A M; Young, J A; Morris, T
2016-08-01
The applied model of mental imagery use proposed an interaction effect between imagery type and imagery ability. This study had two aims: (a) the examination of imagery ability as a moderating variable between imagery type and dispositional flow, and (b) the testing of alternative mediation models. The sample consisted of 367 athletes from Scotland and Australia, who completed the Sport Imagery Questionnaire, Sport Imagery Ability Questionnaire, and Dispositional Flow Scale-2. Hierarchical regression analysis showed direct effects of imagery use and imagery ability on flow, but no significant interaction. Mediation analysis revealed a significant indirect path, indicating a partially mediated relationship (P = 0.002) between imagery use, imagery ability, and flow. Partial mediation was confirmed when the effect of cognitive imagery use and cognitive imagery ability was tested, and a full mediation model was found between motivational imagery use, motivational imagery ability, and flow. The results are discussed in conjunction with potential future research directions on advancing theory and applications. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Pakula, Basia; Carpiano, Richard M; Ratner, Pamela A; Shoveller, Jean A
2016-08-01
To examine the extent to which sexual identity disparities in mental health outcomes (anxiety disorder, mood disorder, anxiety-mood disorder, and co-occurring anxiety or mood disorder and heavy drinking) are mediated by life stress or moderated by a sense of community belonging. This study pooled data from a large, national, multi-year sample of Canadians aged 18-59 years, who self-identified as lesbian, gay, bisexual, or heterosexual (N = 222,548). A series of stratified binary mediation models were fitted. Significance of the indirect effect was determined by using bootstrapping to obtain standard errors and confidence intervals. Sexual minority (versus heterosexual) respondents were significantly more likely to describe their lives as stressful, their sense of community belonging as weak, and had significantly greater odds of the negative mental health outcomes. Perceived life stress partially mediated the effects of sexual identity on the mental health outcomes. The differences between the mediated effects for the gay/lesbian and bisexual subgroups were statistically significant (all p < 0.05). When stratified by sense of community belonging, life stress mediated the relationship with mood disorders for the gay/lesbian group, where a strong sense of community belonging was associated with greater odds of mood disorders for gay/lesbian versus heterosexual respondents. These mediation and moderated mediation models provide further evidence for a social patterning of the mental health disparities experienced by sexual minorities in Canada.
Cilluffo, Giovanna; Ferrante, Giuliana; Fasola, Salvatore; Ciresi, Alessandro; Cardillo, Irene; Tancredi, Giancarlo; Viegi, Giovanni; Giordano, Carla; Scichilone, Nicola; La Grutta, Stefania
2018-04-01
Studies on pulmonary function tests (PFTs) in Growth Hormone Deficiency (GHD) children are lacking. The aims of this study were: (i) to investigate PFTs in GHD pre-pubertal children with respect to Controls, before starting Growth Hormone Therapy (GHT) (T0); (ii) to evaluate changes of PFTs in GHD vs Controls, after 1-year GHT (T1). For both aims the mediation analysis (MA) was applied to evaluate the extent to which the relationship between GHD and PFTs could be ascribed to a height-mediated (indirect) or a GH direct effect. 47 pre-pubertal GHD children (aged 5-14 years) underwent PFTs at T0 and T1. At T0, 47 healthy children matched for age and sex were enrolled as Controls. A MA was performed to assess the relationship between GHD and PFTs and height. Statistical analyses were performed using the statistical software R (https://cran.r-project.org/mirrors.html). A p-value <0.05 was considered significant. At T0, PFTs indices were significantly lower in GHD than in Controls. From T0 to T1 a significant improvement was found in PFTs. The percentages of the mediated effect on FVC, FEV 1 , FEF 25-75% and TLC were <50% at T0, suggesting that the direct effect was prevalent. At T1, the percentages of the mediated effect for spirometry indices were ≥50%, indicating that the indirect (height-mediated) effect was the most relevant. The study shows that pre-pubertal children with GHD have an impairment of lung function not exclusively attributable to the indirect (height-mediated) effect, but also to the direct GH action which is mitigated after 1-year of GHT. Copyright © 2018 Elsevier Ltd. All rights reserved.
How Does MBCT for Depression Work? Studying Cognitive and Affective Mediation Pathways
Batink, Tim; Peeters, Frenk; Geschwind, Nicole; van Os, Jim; Wichers, Marieke
2013-01-01
Mindfulness based cognitive therapy (MBCT) is a non-pharmacological intervention to reduce current symptoms and to prevent recurrence of major depressive disorder. At present, it is not well understood which underlying mechanisms during MBCT are associated with its efficacy. The current study (n = 130) was designed to examine the roles of mindfulness skills, rumination, worry and affect, and the interplay between those factors, in the mechanisms of change in MBCT for residual depressive symptoms. An exploratory but systematic approach was chosen using Sobel-Goodman mediation analyses to identify mediators on the pathway from MBCT to reduction in depressive symptoms. We replicated earlier findings that therapeutic effects of MBCT are mediated by changes in mindfulness skills and worry. Second, results showed that changes in momentary positive and negative affect significantly mediated the efficacy of MBCT, and also mediated the effect of worry on depressive symptoms. Third, within the group of patients with a prior history of ≤ 2 episodes of MDD, predominantly changes in cognitive and to a lesser extent affective processes mediated the effect of MBCT. However, within the group of patients with a prior history of ≥ 3 episodes of MDD, only changes in affect were significant mediators for the effect of MBCT. Trail Registration: Nederlands Trial Register NTR1084 PMID:24009704
Shen, Sipeng; Shi, Qianwen; Bai, Jianling; Li, Jin; Qin, Shukui; Yu, Hao; Chen, Feng
2017-01-01
Apatinib is reported to significantly improve the overall survival (OS) of patients with advanced gastric cancer who have previously failed second-line chemotherapy. However, it is not well understood whether apatinib acts by improving progression or by prolonging post-progression survival. Here, based on phase III clinical trial data, the mediating effect of apatinib on patient overall survival was systematically quantified, through progression-free survival (PFS), post-progression survival (PPS), and the disease control rate (DCR). PFS was the primary mediator of the association between apatinib treatment and OS, with an indirect-effect mean survival time ratio of 1.63 (95%CI 1.35-1.97), which mediated 93.5% of the treatment effect. The DCR was also a significant mediator among secondary efficacy endpoints, and had an indirect-effect mean survival time ratio of 1.47 (95%CI 1.20-1.79, 50.9% mediated). Both primary and other targets of the DCR had similar results. The results indicated that apatinib treatment prolongs progression-free survival rather than post-progression survival, and in turn, leads to improved overall survival. Additionally, our study highlights the value of mediation analysis in clinical trials in providing additional information to build upon traditional primary analysis. PMID:27793017
Huang, Lihong; Wei, Yongyue; Shen, Sipeng; Shi, Qianwen; Bai, Jianling; Li, Jin; Qin, Shukui; Yu, Hao; Chen, Feng
2017-04-25
Apatinib is reported to significantly improve the overall survival (OS) of patients with advanced gastric cancer who have previously failed second-line chemotherapy. However, it is not well understood whether apatinib acts by improving progression or by prolonging post-progression survival. Here, based on phase III clinical trial data, the mediating effect of apatinib on patient overall survival was systematically quantified, through progression-free survival (PFS), post-progression survival (PPS), and the disease control rate (DCR). PFS was the primary mediator of the association between apatinib treatment and OS, with an indirect-effect mean survival time ratio of 1.63 (95%CI 1.35-1.97), which mediated 93.5% of the treatment effect. The DCR was also a significant mediator among secondary efficacy endpoints, and had an indirect-effect mean survival time ratio of 1.47 (95%CI 1.20-1.79, 50.9% mediated). Both primary and other targets of the DCR had similar results. The results indicated that apatinib treatment prolongs progression-free survival rather than post-progression survival, and in turn, leads to improved overall survival. Additionally, our study highlights the value of mediation analysis in clinical trials in providing additional information to build upon traditional primary analysis.
Haerens, Leen; Cerin, Ester; Deforche, Benedicte; Maes, Lea; De Bourdeaudhuij, Ilse
2007-11-09
Although it is important to investigate how interventions work, no formal mediation analyses have been conducted to explain behavioral outcomes in school-based fat intake interventions in adolescents. The aim of the present study was to examine mediation effects of changes in psychosocial determinants of dietary fat intake (attitude, social support, self-efficacy, perceived benefits and barriers) on changes in fat intake in adolescent girls. Data from a 1-year prospective intervention study were used. A random sample of 804 adolescent girls was included in the study. Girls in the intervention group (n = 415) were exposed to a multi-component school-based intervention program, combining environmental changes with a computer tailored fat intake intervention and parental support. Fat intake and psychosocial determinants of fat intake were measured with validated self-administered questionnaires. To assess mediating effects, a product-of-coefficient test, appropriate for cluster randomized controlled trials, was used. None of the examined psychosocial factors showed a reliable mediating effect on changes in fat intake. The single-mediator model revealed a statistically significant suppression effect of perceived barriers on changes in fat intake (p = 0.011). In the multiple-mediator model, this effect was no longer significant, which was most likely due to changes in perceived barriers being moderately related to changes in self-efficacy (-0.30) and attitude (-0.25). The overall mediated-suppressed effect of the examined psychosocial factors was virtually zero (total mediated effect = 0.001; SE = 7.22; p = 0.992). Given the lack of intervention effects on attitudes, social support, self-efficacy and perceived benefits and barriers, it is suggested that future interventions should focus on the identification of effective strategies for changing these theoretical mediators in the desired direction. Alternatively, it could be argued that these constructs need not be targeted in interventions aimed at adolescents, as they may not be responsible for the intervention effects on fat intake. To draw any conclusions regarding mediators of fat-intake change in adolescent' girls and regarding optimal future intervention strategies, more systematic research on the mediating properties of psychosocial variables is needed.
Advances in Testing the Statistical Significance of Mediation Effects
ERIC Educational Resources Information Center
Mallinckrodt, Brent; Abraham, W. Todd; Wei, Meifen; Russell, Daniel W.
2006-01-01
P. A. Frazier, A. P. Tix, and K. E. Barron (2004) highlighted a normal theory method popularized by R. M. Baron and D. A. Kenny (1986) for testing the statistical significance of indirect effects (i.e., mediator variables) in multiple regression contexts. However, simulation studies suggest that this method lacks statistical power relative to some…
Gross Motor Skills and Cardiometabolic Risk in Children: A Mediation Analysis.
Burns, Ryan D; Brusseau, Timothy A; Fu, You; Hannon, James C
2017-04-01
The purpose of this study was to examine the linear relationship between gross motor skills and cardiometabolic risk, with aerobic fitness as a mediator variable, in low-income children from the United States. Participants were a convenience sample of 224 children (mean ± SD age = 9.1 ± 1.1 yr; 129 girls and 95 boys) recruited from five low-income elementary schools from the Mountain West Region of the United States. Gross motor skills were assessed using the Test for Gross Motor Development, 3rd Edition. Gross motor skills were analyzed using a locomotor skill, a ball skill, and a total gross motor skill score. Aerobic fitness was assessed using the Progressive Aerobic Cardiovascular Endurance Run that was administered during physical education class. A continuous and age- and sex-adjusted metabolic syndrome score (MetS) was calculated from health and blood marker measurements collected in a fasted state before school hours. Total effects, average direct effects, and indirect effects (average causal mediation effect) were calculated using a bootstrap mediation analysis method via a linear regression algorithm. The average causal mediation effect of gross locomotor skills on MetS scores, using aerobic fitness as the mediator variable, was statistically significant (β = -0.055, 95% confidence interval = -0.097 to -0.021, P = 0.003). The model explained approximately 17.5% of the total variance in MetS with approximately 43.7% of the relationship between locomotor skills and MetS mediated through aerobic fitness. Ball skills did not significantly relate with cardiometabolic risk. There is a significant relationship between gross locomotor skills and cardiometabolic risk that is partially mediated through aerobic fitness in a sample of low-income children from the United States.
Applying causal mediation analysis to personality disorder research.
Walters, Glenn D
2018-01-01
This article is designed to address fundamental issues in the application of causal mediation analysis to research on personality disorders. Causal mediation analysis is used to identify mechanisms of effect by testing variables as putative links between the independent and dependent variables. As such, it would appear to have relevance to personality disorder research. It is argued that proper implementation of causal mediation analysis requires that investigators take several factors into account. These factors are discussed under 5 headings: variable selection, model specification, significance evaluation, effect size estimation, and sensitivity testing. First, care must be taken when selecting the independent, dependent, mediator, and control variables for a mediation analysis. Some variables make better mediators than others and all variables should be based on reasonably reliable indicators. Second, the mediation model needs to be properly specified. This requires that the data for the analysis be prospectively or historically ordered and possess proper causal direction. Third, it is imperative that the significance of the identified pathways be established, preferably with a nonparametric bootstrap resampling approach. Fourth, effect size estimates should be computed or competing pathways compared. Finally, investigators employing the mediation method are advised to perform a sensitivity analysis. Additional topics covered in this article include parallel and serial multiple mediation designs, moderation, and the relationship between mediation and moderation. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Cohen, Kristen E; Morgan, Philip J; Plotnikoff, Ronald C; Barnett, Lisa M; Lubans, David R
2015-01-01
Numerous studies have identified a positive association between fundamental movement skill (FMS) competency and physical activity in children; however, the causal pathways have not been established. The aim of this study is to determine if changes in FMS competency mediated the effect of the Supporting Children's Outcomes using Rewards, Exercise and Skills (SCORES) intervention on physical activity and cardiorespiratory fitness in children. Eight primary schools (25 classes) and 460 children (aged 8.5 ± 0.6, 54% girls) were randomised to the SCORES intervention or control group for the 12-month study. The outcomes were accelerometer-determined moderate-to-vigorous physical activity (MVPA) and cardiorespiratory fitness. The hypothesised mediators were actual FMS competency and perceived sport competence. Mediation analyses were conducted using multilevel linear analysis in MPlus. From the original sample, 138 (30.0%) and 370 (80.4%) children provided useable physical activity and cardiorespiratory fitness data at post-test assessments. There were significant treatment effects for locomotor skills and overall FMSs. Changes in MVPA were associated with changes in object-control skills, overall FMSs and perceived competence. The overall FMSs had a significant mediating effect on MVPA (AB = 2.09, CI = 0.01-4.55). Overall FMSs (AB = 1.19, CI = 0.002-2.79) and locomotor skills (AB = 0.74, CI = 0.01-1.69) had a significant mediating effect on cardiorespiratory fitness. The results of this study conclude that actual but not perceived movement skill competency mediated the effect of the SCORES intervention on physical activity and cardiorespiratory fitness.
Examining the Role of Anxiety Sensitivity in Sleep Dysfunction Across Anxiety Disorders.
Baker, Amanda W; Keshaviah, Aparna; Goetter, Elizabeth M; Bui, Eric; Swee, Michaela; Rosencrans, Peter L; Simon, Naomi M
2017-01-01
Anxiety Sensitivity (AS) has been associated with sleep difficulties in certain anxiety disorder populations, but no studies have examined cross-diagnostically the role of anxiety sensitivity in sleep dysfunction. Three hundred one participants with generalized anxiety disorder (GAD), social anxiety disorder (SAD), and panic disorder (PD) completed an ancillary questionnaire-based study. Linear regression was used to examine AS and sleep dysfunction, and mediation analyses were used to examine whether AS was a mediator of the effect of primary diagnosis on sleep. AS was associated with increased sleep dysfunction across anxiety disorders, and primary anxiety disorder diagnosis was significantly associated with sleep dysfunction. However, after controlling for AS, primary diagnosis was no longer significant. AS significantly mediated the effects of PD versus SAD and of PD versus GAD on sleep dysfunction, but did not significantly mediate the effect of GAD versus SAD on sleep dysfunction. Taken together, AS appears to be a more important predictor of sleep dysfunction overall, emphasizing the cross-diagnostic nature of AS and bolstering the RDoC initiative approach for treating psychological dysfunction.
Yang, Yi-Feng
2011-06-01
The effects of transformational leadership and satisfaction were studied along with their interconnected effects (mediation and moderation) on commitment to change in the life insurance industry in two samples, sales managers and salespersons. A multiple mediated-moderated regression approach showed mediation and moderation to have statistically significant main effects on change commitment. Transformational leadership and satisfaction made a more important contribution to change commitment while job satisfaction had a mediating and moderating role that could enhance the relationships between leadership and change commitment. This information is of importance in building successful change commitment associations with customers.
Dou, Kai; Nie, Yan-Gang; Wang, Yu-Jie; Liu, Yao-Zhong
2016-01-01
Previous studies have demonstrated that self-control is positively related to life satisfaction, but this association in Chinese employees and its underlying mechanism are less commonly investigated. In this preliminary study the relationships between self-control and life satisfaction and the mediating effect of job satisfaction were tested. Participants were 482 full-time employees (188 male, 294 female) from different cities in China. They answered self-report questionnaires online that assessed self-control, job satisfaction, and life satisfaction. Path analyses were conducted and bootstrap technique was used to judge the significance of the mediation. Self-control was positively related to both job and life satisfaction. More importantly, job satisfaction significantly mediated the association between self-control and life satisfaction. Furthermore, there was no significant difference in the size of the mediating effect between intrinsic and extrinsic job satisfaction. Results of this preliminary study provide further evidence of the positive association between self-control and life satisfaction. Job satisfaction is found to mediate this relationship.
The mediating effects of job satisfaction on turnover intention for long-term care nurses in Taiwan.
Kuo, Huai-Ting; Lin, Kuan-Chia; Li, I-Chuan
2014-03-01
This study explores the mediating effects of job satisfaction on work stress and turnover intention among long-term care nurses in Taiwan. Healthcare institutions face a nursing shortage, and it is important to examine the factors that influence turnover intention among nurses. Excessive levels of work stress may lead to employee dissatisfaction and a significant inverse relationship between work stress and job satisfaction, including subsequent effects on turnover among nurses. However, little is known about the mediating role of job satisfaction on work stress and turnover intention among long-term care nurses. A cross-sectional survey and a correlation design were used. Multistage linear regression was used to test the mediation model. This study showed that job satisfaction significantly mediated the relationship between work stress and turnover intention. Thirty-eight percent of the variance in turnover intention explained by work stress was accounted for by the mediation pathway. The results of this study showed that higher job satisfaction significantly decreased work stress and turnover intention among long-term care nurses. This study provides nursing administrators with a resource to build a supportive environment to increase nurses' job satisfaction and to decrease their stress and turnover. © 2013 John Wiley & Sons Ltd.
Mosher, Catherine E.; Fuemmeler, Bernard F.; Sloane, Richard; Kraus, William E.; Lobach, David F.; Snyder, Denise Clutter; Demark-Wahnefried, Wendy
2013-01-01
This study examined change in self-efficacy as a mediator of the effects of a mailed print intervention on the dietary and exercise practices of newly diagnosed breast and prostate cancer survivors (N = 519). Results indicated that changes in self-efficacy for fat restriction and eating more fruits and vegetables were significant mediators of the intervention’s effects on dietary outcomes at 1-year follow-up. The intervention did not significantly affect self-efficacy for exercise; however, a significant, positive relationship was found between self-efficacy for exercise and exercise duration at follow-up. Findings are largely consistent with Social Cognitive Theory and support the use of strategies to increase self-efficacy in health promotion interventions for cancer survivors. PMID:18300337
Correa-Fernández, Virmarie; Ji, Lingyun; Castro, Yessenia; Heppner, Whitney L.; Vidrine, Jennifer Irvin; Costello, Tracy J.; Mullen, Patricia Dolan; Cofta-Woerpel, Ludmila; Velasquez, Mary M.; Greisinger, Anthony; Cinciripini, Paul M.; Wetter, David W.
2012-01-01
Objective Based on conceptual models of addiction and affect regulation, this study examined the mechanisms linking current major depressive syndrome (MDS) and anxiety syndrome (AS) to postpartum smoking relapse. Method Data were collected in a randomized clinical trial from 251 women who quit smoking during pregnancy. Simple and multiple mediation models of the relations of MDS and AS with postpartum relapse were examined using linear regression, continuation ratio logit models, and a Bootstrapping procedure to test the indirect effects. Results Both MDS and AS significantly predicted postpartum smoking relapse. After adjusting for MDS, AS significantly predicted relapse. However, after adjusting for AS, MDS no longer predicted relapse. Situationally-based self-efficacy, expectancies of controlling negative affect by means other than smoking, and various dimensions of primary and secondary tobacco dependence individually mediated the effect of both MDS and AS on relapse. In multiple mediation models, self-efficacy in negative/affective situations significantly mediated the effect of MDS and AS on relapse. Conclusion The findings underscore the negative impact of depression and anxiety on postpartum smoking relapse, and suggest that the effects of MDS on postpartum relapse may be largely explained by comorbid AS. The current investigation provided mixed support for affect regulation models of addiction. Cognitive and tobacco dependence-related aspects of negative and positive reinforcement significantly mediated the relationship of depression and anxiety with relapse, while affect and stress did not. The findings emphasize the unique role of low agency with respect to abstaining from smoking in negative affective situations as a key predictor of postpartum smoking relapse. PMID:22390410
Correa-Fernández, Virmarie; Ji, Lingyun; Castro, Yessenia; Heppner, Whitney L; Vidrine, Jennifer Irvin; Costello, Tracy J; Mullen, Patricia Dolan; Cofta-Woerpel, Ludmila; Velasquez, Mary M; Greisinger, Anthony; Cinciripini, Paul M; Wetter, David W
2012-08-01
Based on conceptual models of addiction and affect regulation, this study examined the mechanisms linking current major depressive syndrome (MDS) and anxiety syndrome (AS) to postpartum smoking relapse. Data were collected in a randomized clinical trial from 251 women who quit smoking during pregnancy. Simple and multiple mediation models of the relations of MDS and AS with postpartum relapse were examined using linear regression, continuation ratio logit models, and a bootstrapping procedure to test the indirect effects. Both MDS and AS significantly predicted postpartum smoking relapse. After adjusting for MDS, AS significantly predicted relapse. However, after adjusting for AS, MDS no longer predicted relapse. Situationally based self-efficacy, expectancies of controlling negative affect by means other than smoking, and various dimensions of primary and secondary tobacco dependence individually mediated the effect of both MDS and AS on relapse. In multiple mediation models, self-efficacy in negative/affective situations significantly mediated the effect of MDS and AS on relapse. The findings underscore the negative impact of depression and anxiety on postpartum smoking relapse and suggest that the effects of MDS on postpartum relapse may be largely explained by comorbid AS. The current investigation provided mixed support for affect regulation models of addiction. Cognitive and tobacco dependence-related aspects of negative and positive reinforcement significantly mediated the relationship of depression and anxiety with relapse, whereas affect and stress did not. The findings emphasize the unique role of low agency with respect to abstaining from smoking in negative affective situations as a key predictor of postpartum smoking relapse. © 2012 American Psychological Association
ERIC Educational Resources Information Center
Annesi, James J.; Unruh, Jennifer L.; Marti, C. Nathan; Gorjala, Srinivasa; Tennant, Gisele
2011-01-01
The link between physical activity and weight loss has precipitated interest in interventions to foster adherence to exercise. It has been suggested that treatment effects, when significant, should be analyzed to determine theory-based mediators. This research assessed possible mediation of changes in Physical Self-Concept, Exercise Self-Efficacy,…
Varni, James W; Shulman, Robert J; Self, Mariella M; Saeed, Shehzad A; Patel, Ashish S; Nurko, Samuel; Neigut, Deborah A; Saps, Miguel; Zacur, George M; Dark, Chelsea V; Bendo, Cristiane B; Pohl, John F
2017-05-01
To investigate the effects of patient health communication regarding their inflammatory bowel disease (IBD) to their health care providers and significant others in their daily life as a mediator in the relationship between gastrointestinal symptoms and gastrointestinal worry in pediatric patients. The Pediatric Quality of Life Inventory Gastrointestinal Symptoms, Gastrointestinal Worry, and Communication Scales, and Pediatric Quality of Life Inventory 4.0 Generic Core Scales were completed in a 9-site study by 252 pediatric patients with IBD. Gastrointestinal Symptoms Scales measuring stomach pain, constipation, or diarrhea and patient communication were tested for bivariate and multivariate linear associations with Gastrointestinal Worry Scales specific to patient worry about stomach pain or bowel movements. Mediational analyses were conducted to test the hypothesized mediating effects of patient health communication as an intervening variable in the relationship between gastrointestinal symptoms and gastrointestinal worry. The predictive effects of gastrointestinal symptoms on gastrointestinal worry were mediated in part by patient health communication with health care providers/significant others in their daily life. In predictive models using multiple regression analyses, the full conceptual model of demographic variables, gastrointestinal symptoms (stomach pain, constipation, or diarrhea), and patient communication significantly accounted for 46, 43, and 54 percent of the variance in gastrointestinal worry (all Ps < 0.001), respectively, reflecting large effect sizes. Patient health communication explains in part the effects of gastrointestinal symptoms on gastrointestinal worry in pediatric patients with IBD. Supporting patient disease-specific communication to their health care providers and significant others may improve health-related quality of life for pediatric patients with IBD.
Schmidt, Nicole M; Glymour, M Maria; Osypuk, Theresa L
2017-12-01
The Moving to Opportunity (MTO) experiment was a housing mobility program begun in the mid-nineties that relocated volunteer low income families from public housing to rental units in higher opportunity neighborhoods in 5 US cities, using the Section 8 affordable housing voucher program. Compared to the control group who stayed behind in public housing, the MTO voucher group exhibited a harmful main effect for boys' mental health, and a beneficial main effect for girls' mental health. But no studies have examined how this social experiment caused these puzzling, opposite gender effects. The present study tests potential mediating mechanisms of the MTO voucher experiment on adolescent mental health (n=2829, aged 12-19 in 2001-2002). Using Inverse Odds Ratio Weighting causal mediation, we tested whether adolescent substance use comorbidity, social networks, or family mental health acted as potential mediators. Our results document that comorbid substance use (e.g. past 30 day alcohol use, cigarette use, and number of substances used) significantly partially mediated the effect of MTO on boys' behavior problems, resulting in -13% to -18% percent change in the total effect. The social connectedness domain was a marginally significant mediator for boys' psychological distress. Yet no tested variables mediated MTO's beneficial effects on girls' psychological distress. Confounding sensitivity analyses suggest that the indirect effect of substance use for mediating boys' behavior problems was robust, but social connectedness for mediating boys' psychological distress was not robust. Understanding how housing mobility policies achieve their effects may inform etiology of neighborhoods as upstream causes of health, and inform enhancement of future affordable housing programs.
Association between sleep difficulties as well as duration and hypertension: is BMI a mediator?
Carrillo-Larco, R M; Bernabe-Ortiz, A; Sacksteder, K A; Diez-Canseco, F; Cárdenas, M K; Gilman, R H; Miranda, J J
2017-01-01
Sleep difficulties and short sleep duration have been associated with hypertension. Though body mass index (BMI) may be a mediator variable, the mediation effect has not been defined. We aimed to assess the association between sleep duration and sleep difficulties with hypertension, to determine if BMI is a mediator variable, and to quantify the mediation effect. We conducted a mediation analysis and calculated prevalence ratios with 95% confidence intervals. The exposure variables were sleep duration and sleep difficulties, and the outcome was hypertension. Sleep difficulties were statistically significantly associated with a 43% higher prevalence of hypertension in multivariable analyses; results were not statistically significant for sleep duration. In these analyses, and in sex-specific subgroup analyses, we found no strong evidence that BMI mediated the association between sleep indices and risk of hypertension. Our findings suggest that BMI does not appear to mediate the association between sleep patterns and hypertension. These results highlight the need to further study the mechanisms underlying the relationship between sleep patterns and cardiovascular risk factors.
van Beusekom, Gabriël; Baams, Laura; Bos, Henny M W; Overbeek, Geertjan; Sandfort, Theo G M
2016-01-01
We assessed whether homophobic name-calling accounts for the relationship between gender nonconformity and mental health (social anxiety and psychological distress) in a sample of 1,026 Dutch adolescents (boys: n = 517) ages 11 to 16 (Mage = 13.4). We also explored whether this hypothesized mediation differs by sexual attraction and biological sex. Data were collected by means of paper-and-pencil questionnaires at five secondary schools located in urban areas in the Netherlands. Mediation analysis indicated that gender nonconformity was related to both social anxiety and psychological distress partially via homophobic name-calling. Moderated mediation analysis further showed that the mediating role of homophobic name-calling varied according to levels of same-sex attraction (SSA) and biological sex. The mediation effects increased in magnitude when levels of SSA increased and were significant only for adolescents with mean and high levels of SSA. The mediation effects were significant for boys and girls in general, although the mediation effects were stronger for boys than for girls. Our findings emphasize the importance of research and school-level interventions to focus on factors that promote acceptance of cross-gender behavior among adolescents.
van Beusekom, Gabriël; Baams, Laura; Bos, Henny M.W.; Overbeek, Geert J.; Sandfort, Theo G.M.
2018-01-01
We assessed whether homophobic name-calling accounts for the relationship between gender nonconformity and mental health (social anxiety and psychological distress) in a sample of 1,026 Dutch adolescents (boys: n = 517) aged 11–16 years (Mage = 13.4). We also explored whether this hypothesized mediation differs by sexual attraction and biological sex. Data were collected by means of paper–pencil questionnaires at five secondary schools located in urban areas in the Netherlands. Mediation analysis indicated that gender nonconformity was related with both social anxiety and psychological distress partially via homophobic name-calling. Moderated mediation analysis further showed that the mediating role of homophobic name-calling varied according to levels of same-sex attraction (SSA) and biological sex. The mediation effects increased in magnitude when levels of SSA increased and were significant only for adolescents with mean and high levels of SSA. The mediation effects were significant for boys and girls in general, although the mediation effects were stronger for boys than for girls. Our findings emphasize the importance of research and school-level interventions to focus on factors that promote acceptance of cross-gender behaviour among adolescents. PMID:26099017
Effects of Storage-Aged RBC Transfusions on Endothelial Function in Hospitalized Patients
Neuman, Robert; Hayek, Salim; Rahman, Ayaz; Poole, Joseph C.; Menon, Vivek; Sher, Salman; Newman, James L.; Karatela, Sulaiman; Polhemus, David; Lefer, David J.; De Staercke, Christine; Hooper, Craig; Quyyumi, Arshed A.; Roback, John D.
2014-01-01
Background Clinical and animal studies indicate that transfusions of older stored RBCs impair clinical outcomes as compared to fresh RBC transfusions. It has been suggested that this effect is due to inhibition of NO-mediated vasodilation following transfusion of older RBC units. However, to date this effect has not been identified in human transfusion recipients. Study Design and Methods Forty-three hospitalized patients with transfusion orders were randomized to receive either fresh (< 14 days) or older stored (> 21 days) RBC units. Prior to transfusion, and at selected time points after the start of transfusion, endothelial function was assessed using non-invasive flow-mediated dilation assays. Results Following transfusion of older RBC units, there was a significant reduction in NO-mediated vasodilation at 24 hours after transfusion (p=0.045), while fresh RBC transfusions had no effect (p=0.231). Conclusions The present study suggests for the first time a significant inhibitory effect of transfused RBC units stored > 21 days on NO-mediated vasodilation in anemic hospitalized patients. This finding lends further support to the hypothesis that deranged NO signaling mediates adverse clinical effects of older RBC transfusions. Future investigations will be necessary to address possible confounding factors and confirm these results. PMID:25393772
Appleyard, Karen; Yang, Chongming; Runyan, Desmond K
2010-05-01
The current study investigated concurrent and longitudinal mediated and mediated moderation pathways among maltreatment, self-perception (i.e., loneliness and self-esteem), social support, and internalizing and externalizing behavior problems. For both genders, early childhood maltreatment (i.e., ages 0-6) was related directly to internalizing and externalizing behavior problems at age 6, and later maltreatment (i.e., ages 6-8) was directly related to internalizing and externalizing behavior problems at age 8. Results of concurrent mediation and mediated moderation indicated that early maltreatment was significantly related to internalizing and externalizing behavior problems at age 6 indirectly both through age 6 loneliness and self-esteem for boys and through age 6 loneliness for girls. Significant moderation of the pathway from early maltreatment to self-esteem, and for boys, significant mediated moderation to emotional and behavioral problems were found, such that the mediated effect through self-esteem varied across levels of social support, though in an unexpected direction. No significant longitudinal mediation or mediated moderation was found, however, between the age 6 mediators and moderator and internalizing or externalizing problems at age 8. The roles of the hypothesized mediating and moderating mechanisms are discussed, with implications for designing intervention and prevention programs.
Appleyard, Karen; Yang, Chongming; Runyan, Desmond K.
2014-01-01
The current study investigated concurrent and longitudinal mediated and mediated moderation pathways among maltreatment, self perception (i.e., loneliness and self esteem), social support, and internalizing and externalizing behavior problems. For both genders, early childhood maltreatment (i.e., ages 0–6) was related directly to internalizing and externalizing behavior problems at age 6, and later maltreatment (i.e., ages 6–8) was directly related to internalizing and externalizing behavior problems at age 8. Results of concurrent mediation and mediated moderation indicated that early maltreatment was significantly related to internalizing and externalizing behavior problems at age 6 indirectly both through age 6 loneliness and self esteem for boys and through age 6 loneliness for girls. Significant moderation of the pathway from early maltreatment to self esteem, and, for boys, significant mediated moderation to emotional and behavioral problems were found, such that the mediated effect through self esteem varied across levels of social support, though in an unexpected direction. No significant longitudinal mediation or mediated moderation was found, however, between the age 6 mediators and moderator and internalizing or externalizing problems at age 8. The roles of the hypothesized mediating and moderating mechanisms are discussed, with implications for designing intervention and prevention programs. PMID:20423545
Bramsen, Rikke H; Lasgaard, Mathias; Koss, Mary P; Shevlin, Mark; Elklit, Ask; Banner, Jytte
2013-01-01
The present study modeled the direct relationship between child sexual abuse (CSA) and adolescent peer-to-peer sexual victimization (APSV) and the mediated effect via variables representing the number of sexual partners, sexual risk behavior, and signaling sexual boundaries. A cross-sectional study on the effect of CSA on APSV was conducted, utilizing a multiple mediator model. Mediated and direct effects in the model were estimated employing Mplus using bootstrapped percentile based confidence intervals to test for significance of mediated effects. The study employed 327 Danish female adolescents with a mean age of 14.9 years (SD = 0.5). The estimates from the mediational model indicated full mediation of the effect of CSA on APSV via number of sexual partners and sexual risk behavior. The current study suggests that the link between CSA and APSV was mediated by sexual behaviors specifically pertaining to situations of social peer interaction, rather than directly on prior experiences of sexual victimization. The present study identifies a modifiable target area for intervention to reduce adolescent sexual revictimization. © 2013 American Orthopsychiatric Association.
Suk, Min Hyun; Oh, Won Oak; Im, Yeo Jin; Cho, Hun Ha
2015-09-01
This study examined the mediating effect of school nurses' self efficacy, which is one of the significant cognitive factors influencing cultural sensitivity, on the mutual relationships between multicultural attitude and cultural sensitivity in Korean elementary schools. A cross-sectional descriptive survey design was used. Participants were 157 school nurses in elementary schools located in Gyeonggi-do, South Korea. The survey instruments included Teacher Multicultural Attitude Survey, Teacher Efficacy Scale, and Multicultural Sensitivity Scale. Data were analyzed using three regression equations to test the mediation model. The mean score of the school nurses' cultural sensitivity was relatively low. A positive correlation among multicultural attitude, self efficacy, and cultural sensitivity was noted. Self efficacy of school nurses showed a significant mediating effect on the relationships between multicultural attitude and cultural sensitivity. Given the meaningful influence of positive multicultural attitude on cultural sensitivity and significant mediator effect of self efficacy as a school nurse between the two variables, the strategies to cultivate a positive multicultural attitude and enhance school nurses' self efficacy in their unique role should be considered in a training program. School nurses' health care services will benefit from the improvement of cultural sensitivity toward young children from multicultural families. Copyright © 2015. Published by Elsevier B.V.
Chakrapani, Venkatesan; Vijin, Pandara Purayil; Logie, Carmen H; Newman, Peter A; Shunmugam, Murali; Sivasubramanian, Murugesan; Samuel, Miriam
2017-06-01
Few studies have assessed how sexual and gender minority stigmas affect the mental health of trans women and self-identified men who have sex with men (MSM) in India, populations with a high HIV burden. We tested whether social support and resilient coping act as mediators of the effect of sexual and gender minority stigmas on depression as proposed by Hatzenbuehler's psychological mediation framework, or as moderators based on Meyer's minority stress theory. We conducted a cross-sectional survey among trans women (n = 300) and MSM (n = 300) recruited from urban and rural sites in India. Standardized scales were used to measure depression (outcome variable), transgender identity stigma/MSM stigma (predictor variables), and social support and resilient coping (tested as moderators and parallel mediators). The mediation and moderation models were tested separately for trans women and MSM, using Hayes' PROCESS macro in SPSS. Participants' mean age was 29.7 years (standard deviation 8.1). Transgender identity stigma and MSM stigma were significant predictors (significant total and direct effects) of depression, as were social support and resilient coping. Among trans women and MSM, social support and resilient coping mediated (i.e., significant specific indirect effects), but did not moderate, the effect of stigma on depression, supporting the psychological mediation framework. Sexual and gender minority stigmas are associated with depression, with social support and resilient coping as mediators. In addition to stigma reduction interventions at the societal level, future interventions should focus on improving social support and promoting resilience among trans women and MSM in India.
Kim, EunYoung; Cho, Inhyo; Kim, Eun Joo
2017-06-01
This study investigated the mediating effects of loneliness and depression on the relationship between adult attachment and smartphone addiction in university students. A total of 200 university students participated in this study. The data was analysed using descriptive statistics, correlation analysis, and structural equation modeling. There were significant positive relationships between attachment anxiety, loneliness, depression, and smartphone addiction. However, attachment anxiety was not significantly correlated with smartphone addiction. The results also showed that loneliness did not directly mediate between attachment anxiety and smartphone addiction. In addition, loneliness and depression serially mediated between attachment anxiety and smartphone addiction. The results suggest there are mediating effects of loneliness and depression in the relationship between attachment anxiety and smartphone addiction. The hypothesized model was found to be a suitable model for predicting smartphone addiction among university students. Future study is required to find a causal path to prevent smartphone addiction among university students. Copyright © 2017. Published by Elsevier B.V.
Namisi, Francis; Aarø, Leif Edvard; Kaaya, Sylvia; Kajula, Lusajo J; Kilonzo, Gad P; Onya, Hans; Wubs, Annegreet; Mathews, Catherine
2015-12-01
Cluster-randomized controlled trials were carried out to examine effects on sexual practices of school-based interventions among adolescents in three sites in sub-Saharan Africa. In this publication, effects on communication about sexuality with significant adults (including parents) and such communication as a mediator of other outcomes were examined. Belonging to the intervention group was significantly associated with fewer reported sexual debuts in Dar es Salaam only (OR 0.648). Effects on communication with adults about sexuality issues were stronger for Dar es Salaam than for the other sites. In Dar, increase in communication with adults proved to partially mediate associations between intervention and a number of social cognition outcomes. The hypothesized mediational effect of communication on sexual debut was not confirmed. Promoting intergenerational communication on sexuality issues is associated with several positive outcomes and therefore important. Future research should search for mediating factors influencing behavior beyond those examined in the present study.
Liu, Yansong; Yu, Xinnian; Yang, Bixiu; Zhang, Fuquan; Zou, Wenhua; Na, Aiguo; Zhao, Xudong; Yin, Guangzhong
2017-03-21
Overgeneral autobiographical memory has been identified as a risk factor for the onset and maintenance of depression. However, little is known about the underlying mechanisms that might explain overgeneral autobiographical memory phenomenon in depression. The purpose of this study was to test the mediation effects of rumination on the relationship between overgeneral autobiographical memory and depressive symptoms. Specifically, the mediation effects of brooding and reflection subtypes of rumination were examined in patients with major depressive disorder. Eighty-seven patients with major depressive disorder completed the 17-item Hamilton Depression Rating Scale, Ruminative Response Scale, and Autobiographical Memory Test. Bootstrap mediation analysis for simple and multiple mediation models through the PROCESS macro was applied. Simple mediation analysis showed that rumination significantly mediated the relationship between overgeneral autobiographical memory and depression symptoms. Multiple mediation analyses showed that brooding, but not reflection, significantly mediated the relationship between overgeneral autobiographical memory and depression symptoms. Our results indicate that global rumination partly mediates the relationship between overgeneral autobiographical memory and depressive symptoms in patients with major depressive disorder. Furthermore, the present results suggest that the mediating role of rumination in the relationship between overgeneral autobiographical memory and depression is mainly due to the maladaptive brooding subtype of rumination.
Effect of gamma-oryzanol on cytochrome P450 activities in human liver microsomes.
Umehara, Ken; Shimokawa, Yoshihiko; Miyamoto, Gohachiro
2004-07-01
The effects of gamma-oryzanol, a drug mainly used for the treatment of hyperlipidaemia, on several cytochrome P450 (CYP) specific reactions in human liver microsomes were investigated to predict drug interactions with gamma-oryzanol in vivo from in vitro data. The following eight CYP catalytic reactions were used in this study: CYP1A1/2-mediated 7-ethoxyresorufin O-deethylation, CYP2A6-mediated coumarin 7-hydroxylation, CYP2B6-mediated 7-benzyloxyresorufin O-debenzylation, CYP2C8/9-mediated tolbutamide methylhydroxylation, CYP2C19-mediated S-mephenytoin 4'-hydroxylation, CYP2D6-mediated bufuralol 1'-hydroxylation, CYP2E1-mediated chlorzoxazone 6-hydroxylation, and CYP3A4-mediated testosterone 6beta-hydroxylation. gamma-Oryzanol had little inhibitory effects on CYP activities, indicating that this compound would not be expected to cause clinically significant interactions with other CYP-metabolized drugs at expected therapeutic concentrations.
Ma, Bing; Liu, Shanshi; Liu, Donglai; Wang, Hongchun
2016-04-01
This research focuses on investigating whether organisational identification mediates the effects of job security on in-role behaviour and extra-role behaviour and how these mediation mechanisms differ according to gender. Through analysing 212 supervisor-subordinate dyads from a Chinese air transportation group, the research indicated that organisational identification partially mediated the effect of job security on in-role behaviour and fully mediated the effect of job security on extra-role behaviour. A multi-group analysis also showed that there were significant differences between male and female employees in these relationships. In addition, moderated mediation analyses showed that gender moderated the indirect effects of job security on in-role behaviour and extra-role behaviour through organisational identification. Limitations and implications of these findings are discussed. © 2015 International Union of Psychological Science.
Athay, M. Michele
2012-01-01
This paper presents the psychometric evaluation of the Satisfaction with Life Scale (SWLS; Diener, Emmons, Larson & Griffen, 1985) used with a large sample (N = 610) of caregivers for youth receiving mental health services. Methods from classical test theory, factor analysis and item response theory are utilized. Additionally, this paper investigates whether caregiver strain mediates the effect of youth symptom severity on caregiver life satisfaction (N = 356). Bootstrapped confidence intervals are used to determine the significance of the mediated effects. Results indicate that the SWLS is a psychometrically sound instrument to be used with caregivers of clinically-referred youth. Mediation analyses found that the effect of youth symptom severity on caregiver life satisfaction is mediated by caregiver strain but that the mediation effect differs based on the type of youth symptoms. Caregiver strain is a partial mediator when externalizing symptoms are measured and a full mediator when internalizing symptoms are measured. Implications for future research and clinical practice are discussed. PMID:22407554
Hedman, Erik; Hesser, Hugo; Andersson, Erik; Axelsson, Erland; Ljótsson, Brjánn
2017-08-01
Exposure-based cognitive behavior therapy (CBT) has been shown to be effective in the treatment of severe health anxiety, but little is known about mediators of treatment effect. The aim of the present study was to investigate mindful non-reactivity as a putative mediator of health anxiety outcome using data from a large scale randomized controlled trial. We assessed mindful non-reactivity using the Five Facets Mindfulness Questionnaire-Non-Reactivity scale (FFMQ-NR) and health anxiety with the Short Health Anxiety Inventory (SHAI). Participants with severe health anxiety (N=158) were randomized to internet-delivered exposure-based CBT or behavioral stress management (BSM) and throughout the treatment, both the mediator and outcome were measured weekly. As previously reported, exposure-based CBT was more effective than BSM in reducing health anxiety. In the present study, latent process growth modeling showed that treatment condition had a significant effect on the FFMQ-NR growth trajectory (α-path), estimate=0.18, 95% CI [0.04, 0.32], p=.015, indicating a larger increase in mindful non-reactivity among participants receiving exposure-based CBT compared to the BSM group. The FFMQ-NR growth trajectory was significantly correlated with the SHAI trajectory (β-path estimate=-1.82, 95% CI [-2.15, -1.48], p<.001. Test of the indirect effect, i.e. the estimated mediation effect (αβ) revealed a significant cross product of -0.32, which was statistically significant different from zero based on the asymmetric confidence interval method, 95% CI [-0.59, -0.06]. We conclude that increasing mindful non-reactivity may be of importance for achieving successful treatment outcomes in exposure-based CBT for severe health anxiety. Copyright © 2017 Elsevier Ltd. All rights reserved.
Sjöwall, Douglas; Thorell, Lisa B.
2014-01-01
Attention deficit hyperactivity disorder (ADHD) is associated with multiple neuropsychological deficits and the present study aimed to investigate to what extent these deficits are related to the functional impairments associated with the disorder. The results showed that all executive functioning deficits and reaction time variability acted as mediators in the relation between ADHD and academic achievement. However, only the effect of working memory for language skills, and the effects of reaction time variability and working memory for mathematics, remained significant when studying independent effects. Regulation of anger was a significant mediator for peer problems. Gender or symptoms of oppositional defiant disorder (ODD) or conduct disorder (CD) did not moderate these findings. PMID:24742310
Ju, Soyoung; Lee, Yanghee
2018-02-01
The purpose of this study is to identify the developmental trajectories of peer attachment, self-esteem, depression, and child maltreatment, and to understand the longitudinal mediation effects that peer attachment and self-esteem have on the influence of perceived abuse on early adolescent depression. This study uses Year 1 to Year 5 data of the 4th grader panel of the Korea Youth Panel Survey (KYPS) and utilizes a multivariate latent growth model to analyze the main variables in the applicable data between 5th (i.e., Year 2) and 8th (i.e., Year 5) grades. The results indicate that from the 5th to the 8th grade, the degree of abuse and depression increases while self-esteem gradually decreases with slowly lowering peer attachment. A significant distribution of the initial values and the rate of change were present for all main variables of the study, confirming individual differences in time wise changes. Further, more exposure to abuse correlated with a decrease in self-esteem, while an increase in self-esteem greatly reduced depression. The initial value of self-esteem showed a partial mediation effect, whereas the rate of change indicated a full mediation effect with a significant longitudinal mediation effect. More experience of abuse during early adolescence indicated a lower degree of peer attachment, and a higher peer attachment was related to decreased depression. A significant partial mediation effect was present for both the initial value and the rate of change of peer attachment, and a longitudinal mediation effect was present. This study confirmed that self-esteem in early adolescents is an important protective factor that can greatly reduce the degree of depression, and suggests continuous interventions conducted to increase self-esteem in adolescence. Furthermore, by determining that peer attachment decreases the degree of depression in children at risk, the study emphasizes the healing aspect of adolescent peer attachment. Copyright © 2017 Elsevier Ltd. All rights reserved.
A cautionary note on the power of the test for the indirect effect in mediation analysis.
Loeys, Tom; Moerkerke, Beatrijs; Vansteelandt, Stijn
2014-01-01
Recent simulation studies have pointed to the higher power of the test for the mediated effect vs. the test for the total effect, even in the presence of a direct effect. This has motivated applied researchers to investigate mediation in settings where there is no evidence of a total effect. In this paper we provide analytical insight into the circumstances under which higher power of the test for the mediated effect vs. the test for the total effect can be expected in the absence of a direct effect. We argue that the acclaimed power gain is somewhat deceptive and comes with a big price. On the basis of the results, we recommend that when the primary interest lies in mediation only, a significant test for the total effect should not be used as a prerequisite for the test for the indirect effect. However, because the test for the indirect effect is vulnerable to bias when common causes of mediator and outcome are not measured or not accounted for, it should be evaluated in a sensitivity analysis.
A cautionary note on the power of the test for the indirect effect in mediation analysis
Loeys, Tom; Moerkerke, Beatrijs; Vansteelandt, Stijn
2015-01-01
Recent simulation studies have pointed to the higher power of the test for the mediated effect vs. the test for the total effect, even in the presence of a direct effect. This has motivated applied researchers to investigate mediation in settings where there is no evidence of a total effect. In this paper we provide analytical insight into the circumstances under which higher power of the test for the mediated effect vs. the test for the total effect can be expected in the absence of a direct effect. We argue that the acclaimed power gain is somewhat deceptive and comes with a big price. On the basis of the results, we recommend that when the primary interest lies in mediation only, a significant test for the total effect should not be used as a prerequisite for the test for the indirect effect. However, because the test for the indirect effect is vulnerable to bias when common causes of mediator and outcome are not measured or not accounted for, it should be evaluated in a sensitivity analysis. PMID:25628585
Takaki, Jiro; Taniguchi, Toshiyo; Fukuoka, Etsuko; Fujii, Yasuhito; Tsutsumi, Akizumi; Nakajima, Kazuo; Hirokawa, Kumi
2010-01-01
The purpose of this study was to assess whether workplace bullying mediates between job strain, evaluated by the job demand-control model, and symptoms of depression and sleep disturbance. The subjects in this cross-sectional study were recruited from all the workers (N=2,634) at 50 organizations in Japan. Due to missing data, the numbers of subjects included in the analyses varied from 1,646 to 2,062 (response rates varied from 62.5% to 78.2%). Job strain and workplace social support, workplace bullying, depression, and sleep disturbance were assessed using the Japanese versions of the Job Content Questionnaire, the Negative Acts Questionnaire, the Center for Epidemiologic Studies Depression Scale, and the Pittsburgh Sleep Quality Index, respectively. Mediation analysis followed the approach outlined by Baron and Kenny. We quantitatively estimated the mediation effects and tested their significance after adjustment for various combinations of demographic variables and workplace social support. Total effects of job strain index on depression or sleep disturbance were all positive and significant (p<0.05) in both genders. Mediation effects of workplace bullying were also all positive and significant (p<0.05) in both genders. Even after adjustment for workplace social support, the mediation effects were decreased, especially in women, but remained significant (p<0.05). Workplace bullying seems to play important roles in the relationships of job strain with depression or sleep disturbance in both genders.
Kuerbis, Alexis; Mereish, Ethan H; Hayes, Marie; Davis, Christine M; Shao, Sijing; Morgenstern, Jon
2017-01-01
Minority stress theory is one of the primary theories used to understand substance use among lesbian, gay, and bisexual populations. This study tested whether drinking to cope with stress (DTC), loneliness, and gay community participation (GCP) mediated the relationship between one type of minority stress (i.e., internalized heterosexism) and behavioral health outcomes. Using secondary data analysis and the PROCESS procedure, relationships between internalized heterosexism, the mediators (DTC, loneliness, and GCP), and outcomes (heavy drinking, alcohol problems, and psychological distress) were explored, both cross-sectionally and in a lagged manner, among both treatment-seeking and non-treatment-seeking problem drinking men who have sex with men. Problem drinkers (N = 187) were assessed, provided brief normative feedback about their drinking, given the choice to receive brief alcohol use disorder treatment or change on their own, and then followed for 9 months. Cross-sectional findings revealed that internalized heterosexism was significantly associated with heavy drinking, alcohol problems, and psychological distress. DTC emerged as a significant mediator of internalized heterosexism for all the health outcomes. Loneliness and GCP were significant mediators of internalized heterosexism for alcohol problems and psychological distress. Multiple mediation models reveal that all three mediators significantly contribute to internalized heterosexism's effect on health outcomes. Lagged analyses did not yield any significant indirect effects. DTC, loneliness, and GCP all play an integral, mediational role in the relationship between internalized heterosexism and alcohol problems and psychological distress. Findings underscore the necessity of addressing internalized heterosexism in psychosocial interventions along with coping skills training, emphasizing culturally relevant social support and loneliness.
Park, Irene J. K.; Wang, Lijuan; Williams, David R.; Alegría, Margarita
2016-01-01
Although prior research has consistently documented the association between racial/ethnic discrimination and poor mental health outcomes, the mechanisms that underlie this link are still unclear. The present three-wave longitudinal study tested the mediating role of anger regulation in the discrimination—mental health link among 269 Mexican-origin adolescents (Mage = 14.1 years, SD = 1.6; 57% girls), 12 – 17 years old. Three competing anger regulation variables were tested as potential mediators: outward anger expression, anger suppression, and anger control. Longitudinal mediation analyses were conducted using multilevel modeling that disaggregated within-person effects from between-person effects. Results indicated that outward anger expression was a significant mediator; anger suppression and anger control were not significant mediators. Within a given individual, greater racial/ethnic discrimination was associated with more frequent outward anger expression. In turn, more frequent outward anger expression was associated with higher levels of anxiety and depression at a given time point. Gender, age, and nativity status were not significant moderators of the hypothesized mediation models. By identifying outward anger expression as an explanatory mechanism in the discrimination-distress link among Latino youths, this study points to a malleable target for prevention and intervention efforts aimed at mitigating the detrimental impact of racism on Latino youths’ mental health during the developmentally critical period of adolescence. PMID:27893238
Zhu, Wenzhen; Wang, Chiachih Dc; Chong, Chu Chian
2016-11-01
In the current study, we tested a moderated mediation model in which cultural orientation moderated the mediation model of adult attachment-perceived social support-depressive symptoms, using 2 comparable cross-cultural samples of college students recruited from China and the U.S. (n = 363 for each group). Results indicated that perceived social support mediated the effect of attachment anxiety on depressive symptoms as well as the link between attachment avoidance and depression in both samples. Moderated mediation analyses using PROCESS revealed that interdependent self-construal significantly buffered the indirect effect of attachment avoidance (via perceived social support) on depressive symptoms. The findings indicated significant differences in the mediation models between the U.S. and China groups and interdependent self-construal accounted for the between-country differences. Limitations, implications of the findings, and future research directions are discussed from the perspectives of cross-cultural variation of adult attachment functioning. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Ban, Jiyoon; Oh, Insoo
2016-11-01
The current study examined the mediating effects of the teacher and peer relationships between parental abuse/neglect and a child's emotional/behavioral problems. A total of 2070 student surveys from the panel of the Korean Child Youth Panel Study (KCYPS) were analyzed by path analysis. The key findings of this study are outlined below. Firstly, parental physical and emotional abuse and neglect had significant effects on children's problems. The direct effect of parental abuse on emotional/behavioral problems was higher than the direct effect of parental neglect on emotional/behavioral problems. Secondly, the teacher relationship partially mediated the effects of the parental abuse/neglect on emotional/behavioral problems. Thirdly, the peer relationship also partially mediated the effects of parental abuse/neglect on children's emotional/behavioral problems. The indirect effect of parental neglect via teacher relationships and peer relationships was stronger than the indirect effect of parental abuse. This study is significant in that it identified that parental abuse/neglect was mediated by the teacher and peer relationship, thereby suggesting an implication for effective intervention with children who have suffered abuse and neglect. In terms of the teacher and peer relationship, understanding the influence of parental abuse and neglect on children's problems was discussed, and the limitations and recommendations for future study were suggested. Copyright © 2016 Elsevier Ltd. All rights reserved.
Gormley, Matthew J; Pinho, Trevor; Pollack, Brittany; Puzino, Kristina; Franklin, Melanie K; Busch, Chelsea; DuPaul, George J; Weyandt, Lisa L; Anastopoulos, Arthur D
2018-02-01
To test if the relationship between ADHD and academic achievement is mediated by service utilization and/or study skills, and if these mediation effects are moderated by parental education level. A bootstrapping method within structural equation modeling was used with data from 355 first year college students meeting strict criteria for ADHD or clearly without ADHD to test the mediation and moderation effects. Study skills, but not service utilization, significantly mediated the relationship between ADHD status and GPA; however, this relationship was not significant among students with at least one parent holding a master's degree or higher. Among first year college students study skills may be a more salient predictor of educational outcomes relative to ADHD status. Additional research into support services for college students with ADHD is needed, however, results suggest interventions targeting study skills may hold particular promise for these students.
Kaul, Anne; Gläser, Sven; Hannemann, Anke; Stubbe, Beate; Felix, Stefan B; Nauck, Matthias; Ewert, Ralf; Friedrich, Nele
2017-04-01
Vitamin D deficiency is discussed to be associated with lung health. While former studies focused on subjects suffering from pulmonary diseases, we aimed to investigate the association of 25-hydroxy vitamin D [25(OH)D] with lung function in the general population and examined whether mediating effects of inflammation, glycemic control or renal function exist. 1404 participants from the Study of Health in Pomerania with pulmonary function testing assessed by expiratory volume in 1 s (FEV 1 ), forced vital capacity (FVC), total lung capacity and Krogh index were used. Adjusted analysis of variance, linear regression models and mediation analyses were performed. Significant positive associations between 25(OH)D levels and FEV 1 , FVC and Krogh index were found. Mediator analyses revealed no mediating effect of inflammation (fibrinogen), glycemic control (HbA1c) or renal function (eGFR) on associations with FEV 1 or FVC. With respect to Krogh-Index, the association to 25(OH)D was slightly mediated by fibrinogen with a proportion mediated of 9.7%. Significant positive associations of 25(OH)D with lung function were revealed in a general population. The proposed mediating effects of inflammation, glycemic control and renal function on these relations were not confirmed. Further studies examining the causality of the association between 25(OH)D and lung function are necessary. Copyright © 2017 Elsevier Ltd. All rights reserved.
Mediating the distal crime-drug relationship with proximal reactive criminal thinking.
Walters, Glenn D
2016-02-01
This article describes the results of a study designed to test whether reactive criminal thinking (RCT) does a better job of mediating the crime → drug relationship than it does mediating the drug → crime relationship after the direct effects of crime on drug use/dependency and of drug use/dependency on crime have been rendered nonsignificant by control variables. All 1,170 male members of the Pathways to Desistance study (Mulvey, 2012) served as participants in the current investigation. As predicted, the total (unmediated) effects of crime on substance use/dependence and of substance use/dependence on crime were nonsignificant when key demographic and third variables were controlled, although the indirect (RCT-mediated) effect of crime on drug use was significant. Proactive criminal thinking (PCT), by comparison, failed to mediate either relationship. The RCT continued to mediate the crime → drug relationship and the PCT continued to not mediate either relationship when more specific forms of offending (aggressive, income) and substance use/dependence (drug use, substance-use dependency symptoms) were analyzed. This offers preliminary support for the notion that even when the total crime-drug effect is nonsignificant the indirect path from crime to reactive criminal thinking to drugs can still be significant. Based on these results, it is concluded that mediation by proximal reactive criminal thinking is a mechanism by which distal measures of crime and drug use/dependence are connected. (c) 2016 APA, all rights reserved).
Siveen, K S; Kuttan, Girija
2012-01-01
Cell-mediated immunity offers protection against virus-infected cells and tumor cells, involves activation of natural killer (NK) cells, production of antigen-specific cytotoxic T-lymphocytes, and release of various cytokines in response to an antigen. Administration of an ethanolic extract of Aerva lanata was found to stimulate cell-mediated immunological responses in normal and tumor-bearing BALB/c mice. A significant enhancement in NK cell activity in both normal and tumor-bearing hosts was observed after administration of A. lanata. Antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent complement-mediated cytotoxicity (ACC) were significantly enhanced as well in both sets of treated hosts. In addition, in vivo production of IL-2 and IFNg were each significantly enhanced by extract treatment. The stimulatory effect of A. lanata on cytotoxic T-lymphocyte (CTL) production was determined by Winn's neutralization assay using CTL-sensitive EL4 thymoma cells. A. lanata treatment caused a significant increase in CTL production in both in vivo and in vitro models, in each case as indicated by a significant increase in the life-spans of tumor-injected mice. Taken together, all of these results in the murine model indicate that administration of an ethanolic extract of A. lanata could enhance the cell-mediated anti-tumor response.
Ryu, Ehri; West, Stephen G.; Sousa, Karen H.
2010-01-01
We extended Wilson and Cleary's (1995) health-related quality of life model to examine the relationships among symptoms status (Symptoms), functional health (Disability), and quality of life (QOL). Using a community sample (N = 956) of male HIV positive patients, we tested a mediation model in which the relationship between Symptoms and QOL is partially mediated by Disability. Common and unique ideas from three approaches to examining moderation of effects in mediational models (Edwards & Lambert, 2007; Preacher, Rucker, & Hayes, 2007; MacKinnon, 2008) were used to test whether (a) the direct relationship of Symptoms to QOL and (b) the relationship of Disability to QOL are moderated by age. In the mediation model, both the direct and the indirect (mediated) effects were significant. The direct relationship of Symptoms to QOL was significantly moderated by age, but the relationship of Disability to QOL was not. High Symptoms were associated with lower QOL at all ages, but that this relationship became stronger at older ages. We compare the three approaches and consider their advantages over traditional approaches to combining mediation and moderation. PMID:20706561
Grummon, Anna H; Vaughn, Amber; Jones, Deborah J; Ward, Dianne S
2017-08-01
Children exposed to multiple stressors are more likely to be overweight, but little is known about the mechanisms explaining this association. This cross-sectional study examined whether children exposed to multiple stressors had higher waist circumference, and whether this association was mediated through children's television time. Participants were 319 parent-child dyads. Children were 2-5 years old and had at least one overweight parent (BMI ≥ 25 kg/m 2 ). Data were collected at baseline of a larger childhood obesity prevention study and included information on psychosocial stressors (e.g., parenting stress), demographic stressors (e.g., low income), children's television time, and children's waist circumference. Two cumulative risk scores were created by summing stressors in each domain (demographic and psychosocial). Mediation and moderated mediation analyses were conducted. Indirect effects of both cumulative risk scores on waist circumference through television time were not significant; however, moderated mediation analyses found significant moderation by gender. The indirect effects of both risk scores on waist circumference through television time were significant and positive for girls, but near-zero for boys. Reducing television time should be explored as a strategy for buffering against the negative health effects of exposure to multiple stressors among girls. Longitudinal and intervention research is needed to confirm these results and to identify mediating factors between cumulative risk and body weight among boys.
Negriff, Sonya; Trickett, Penelope K
2012-11-01
Early pubertal timing has received considerable empirical support as a risk for adolescent substance use. However, few studies have examined the mediators linking these variables. Therefore, the aims of this study were (1) to examine peer substance use as a mediator between pubertal timing and adolescent substance use longitudinally and (2) to test gender and maltreatment experience as moderators of the mediational model. Data were obtained from time 1, 2, and 3 of a longitudinal study of maltreatment and development. At time 1 the sample was comprised of 303 maltreated and 151 comparison children aged 9-13 years (213 females and 241 males). Longitudinal mediation was tested using structural equation modeling and moderating effects were tested using multiple group analysis. Peer substance use mediated the relationship between early pubertal timing and later adolescent substance use for the total sample. Moderation analyses indicated this significant indirect effect did not differ for males and females. However, it did differ for maltreated versus comparison adolescents with the mediational effect only remaining significant for the comparison group. This is one of the first studies to examine peer substance use as a mediator of pubertal timing and adolescent substance use using a longitudinal design. Early maturing males are at equal risk to early maturing females for interacting with peers that may draw them into substance use. Additionally, the findings indicate that while peers are mediators for comparison adolescents a different mechanism may link early puberty to substance use for maltreated adolescents. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
You, Sukkyung; Lim, Sun Ah
2015-08-01
This study investigated the long-term relationship between abusive parenting and adolescent mental health, and the path to delinquent behavior. Longitudinal data from 5th through 7th graders from the Korean Children and Youth Panel Survey (KCYPS) were analyzed to examine if abusive parenting was a predictor of early adolescent delinquency behavior, via aggression and depression as mediating factors. The results were as follows. First, parental abuse (both emotional and physical) was found to have significant effects on children's psychosocial factors (aggression and depression), while parental neglect (both emotional and physical) had significant effects on depression alone and not on aggression. Second, aggression exerted significant effects on both violent and non-violent delinquent behaviors, while depression had a significant effect on only non-violent delinquent behaviors. Third, children's psychosocial factors (aggression and depression) played significant mediating roles between earlier abusive parenting and delinquent behaviors. Fourth, for children living in a family with their grandparents, paths from abusive parenting, psychosocial adaptation, and later delinquent behaviors were not significant, implying that living with grandparents played a protective factor in these relationships. Copyright © 2015 Elsevier Ltd. All rights reserved.
Can Computer-Mediated Interventions Change Theoretical Mediators of Safer Sex? A Meta-Analysis
ERIC Educational Resources Information Center
Noar, Seth M.; Pierce, Larson B.; Black, Hulda G.
2010-01-01
The purpose of this study was to conduct a meta-analysis of computer-mediated interventions (CMIs) aimed at changing theoretical mediators of safer sex. Meta-analytic aggregation of effect sizes from k = 20 studies indicated that CMIs significantly improved HIV/AIDS knowledge, d = 0.276, p less than 0.001, k = 15, N = 6,625; sexual/condom…
GPER-independent effects of estrogen in rat aortic vascular endothelial cells.
Ding, Q; Hussain, Y; Chorazyczewski, J; Gros, R; Feldman, R D
2015-01-05
GPER (aka GPR30) has been identified as an important mechanism by which estrogen mediates its effects. Previous studies from our laboratories and those of others have demonstrated that GPER activation mediates a range of vascular contractile and growth regulatory responses. However, the importance of GPER in mediating the actions of estradiol (E2) in rat aortic endothelial cells is unclear. Therefore, we sought to determine the importance of GPER vs. the "classical" estrogen receptor (ER) in mediating the endothelial growth regulatory effects of E2. To do this we assessed the effect of E2 in regulating phosphoERK content and apoptotic rates in rat aortic endothelial cells and the role of GPER in mediating these effects. E2 mediated a concentration-dependent inhibition of both ERK phosphorylation and serum deprivation-induced apoptosis with a maximal effect at a concentration of 10 nM. Pretreatment with the ER antagonist ICI 182780 abolished E2-mediated inhibition of both ERK phosphorylation and apoptosis. In contrast, pretreatment with GPER antagonist G15 had no significant effect on E2-mediated inhibition of ERK phosphorylation or on apoptosis. Further, downregulation of GPER expression with a GPER shRNA adenovirus did not block E2-mediated inhibitory effects on ERK phosphorylation and apoptosis. In fact, these inhibitory effects of E2 were further enhanced by GPER downregulation. Downregulation of ERα expression reversed the E2-mediated inhibitory effects to stimulatory effects. E2's phosphoERK and apoptosis stimulatory effects seen with ERα downregulation are attenuated by pretreatment with G15. In conclusion, in rat aortic endothelial cells, E2-mediated endothelial effects are predominantly driven by ER and not by GPER. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Koronczai, Beatrix; Kökönyei, Gyöngyi; Urbán, Róbert; Kun, Bernadette; Pápay, Orsolya; Nagygyörgy, Katalin; Griffiths, Mark D; Demetrovics, Zsolt
2013-07-01
Given that dissatisfaction with bodily appearance can sometimes lead to the avoidance of personal contacts and the increase of internet use, this study examines this relationship. The direct role of dissatisfaction with bodily appearance along with the possible mediation effects of depression, anxiety and self-esteem were tested. A total of 694 participants completed an online questionnaire (58.5% male, mean age 21.5 years), containing measures on problematic internet use, depression and anxiety symptoms, self-esteem and satisfaction with body image. Path analyses were used to test direct and indirect effects. Satisfaction with body appearance had a significant negative direct effect on problematic internet use among both sexes. Though, satisfaction with body appearance had a positive effect on self-esteem and negative on anxiety, neither self-esteem nor anxiety had a direct significant effect on problematic internet use. The effect of dissatisfaction with body appearance was mediated via the self-esteem-depression path toward problematic internet use. Dissatisfaction with physical appearance seems to have a significant role in individuals' immersing themselves in internet use.
Choi, Han Gyo; Ahn, Sung Hee
2016-02-01
The aim of this study was to examine the mediating effect of empowerment in the relationship of nurse managers' authentic leadership, with nurses' organizational commitment and job satisfaction. The participants in this study were 273 registered nurses working in five University hospitals located in Seoul and Gyeonggi Province. The measurements included the Authentic Leadership Questionnaire, Condition of Work Effectiveness Questionnaire-II, Organizational Commitment Questionnaire and Korea-Minnesota Satisfaction Questionnaire. Data were analyzed using t-test, ANOVA, Scheffé test, Pearson correlation coefficients, simple and multiple regression techniques with the SPSS 18.0 program. Mediation analysis was performed according to the Baron and Kenny method and Sobel test. There were significant correlations among authentic leadership, empowerment, organizational commitment and job satisfaction. Empowerment showed perfect mediating effects in the relationship between authentic leadership and organizational commitment. It had partial mediating effects in the relationship between authentic leadership and job satisfaction. In this study, nurse managers' authentic leadership had significant influences on nurses organizational commitment and job satisfaction via empowerment. Therefore, to enhance nurses' organizational commitment and job satisfaction, it is necessary to build effective strategies to enhance nurse manager's authentic leadership and to develop empowering education programs for nurses.
Work stressors and impaired sleep: rumination as a mediator.
Berset, Martial; Elfering, Achim; Lüthy, Stefan; Lüthi, Simon; Semmer, Norbert K
2011-04-01
An association between stress at work and impaired sleep is theoretically plausible and supported by empirical evidence. The current study's main aim was to investigate how the influence of stressors is carried over into the evening and the night. We assume that this relationship is mediated by perseverative cognitions. We tested this assumption in two cross-sectional samples with structural equation modeling, using bootstrapped standard errors to test for significance. Effort–reward imbalance and time pressure were used as stressors, and rumination as a measure for perseverative cognitions. Results show that the stressors are related to perseverative cognitions, and these are related to impaired sleep in both samples. Indirect effects are significant in both samples. With rumination controlled, direct effects of stressors on sleep are only significant in one out of four cases. Thus, there is full mediation in three out of four cases, and partial mediation in the fourth one. Our results underscore the notion that perseverative cognitions are crucial for transferring negative effects of work stressors into private life, including sleep, thus hindering individuals to successfully recover.
Butler, Stephen F; Villapiano, Albert; Malinow, Andrew
2009-12-01
People tend to disclose more personal information when communication is mediated through the use of a computer. This study was conducted to examine the impact of this phenomenon on the way respondents answer questions during computer-mediated, self-administration of the Addiction Severity Index (ASI) called the Addiction Severity Index-Multimedia Version((R)) (ASI-MV((R))). A sample of 142 clients in substance abuse treatment was administered the ASI via an interviewer and the computerized ASI-MV((R)), three to five days apart in a counterbalanced order. Seven composite scores were compared between the two test administrations using paired t-tests. Post hoc analyses examined interviewer effects. Comparisons of composite scores for each of the domains between the face-to-face administered and computer-mediated, self-administered ASI revealed that significantly greater problem severity was reported by clients in five of the seven domains during administration of the computer-mediated, self-administered version compared to the trained interviewer version. Item analyses identified certain items as responsible for significant differences, especially those asking clients to rate need for treatment. All items that were significantly different between the two modes of administration revealed greater problem severity reported on the ASI-MV((R)) as compared to the interview administered assessment. Post hoc analyses yielded significant interviewer effects on four of the five domains where differences were observed. These data support a growing literature documenting a tendency for respondents to be more self-disclosing in a computer-mediated format over a face-to-face interview. Differences in interviewer skill in establishing rapport may account for these observations.
Wang, Jian; Spitz, Margaret R; Amos, Christopher I; Wu, Xifeng; Wetter, David W; Cinciripini, Paul M; Shete, Sanjay
2012-01-01
A mediation model explores the direct and indirect effects between an independent variable and a dependent variable by including other variables (or mediators). Mediation analysis has recently been used to dissect the direct and indirect effects of genetic variants on complex diseases using case-control studies. However, bias could arise in the estimations of the genetic variant-mediator association because the presence or absence of the mediator in the study samples is not sampled following the principles of case-control study design. In this case, the mediation analysis using data from case-control studies might lead to biased estimates of coefficients and indirect effects. In this article, we investigated a multiple-mediation model involving a three-path mediating effect through two mediators using case-control study data. We propose an approach to correct bias in coefficients and provide accurate estimates of the specific indirect effects. Our approach can also be used when the original case-control study is frequency matched on one of the mediators. We employed bootstrapping to assess the significance of indirect effects. We conducted simulation studies to investigate the performance of the proposed approach, and showed that it provides more accurate estimates of the indirect effects as well as the percent mediated than standard regressions. We then applied this approach to study the mediating effects of both smoking and chronic obstructive pulmonary disease (COPD) on the association between the CHRNA5-A3 gene locus and lung cancer risk using data from a lung cancer case-control study. The results showed that the genetic variant influences lung cancer risk indirectly through all three different pathways. The percent of genetic association mediated was 18.3% through smoking alone, 30.2% through COPD alone, and 20.6% through the path including both smoking and COPD, and the total genetic variant-lung cancer association explained by the two mediators was 69.1%.
Rogers, Laura Q; Courneya, Kerry S; Anton, Phillip M; Hopkins-Price, Patricia; Verhulst, Steven; Robbs, Randall S; Vicari, Sandra K; McAuley, Edward
2017-04-01
Most breast cancer survivors do not meet physical activity recommendations. Understanding mediators of physical activity behavior change can improve interventions designed to increase physical activity in this at-risk population. Study aims were to determine the 3-month Better Exercise Adherence after Treatment for Cancer (BEAT Cancer) behavior change intervention effects on social cognitive theory constructs and the mediating role of any changes on the increase in accelerometer-measured physical activity previously reported. Post-treatment breast cancer survivors (N = 222) were randomized to BEAT Cancer or usual care. Assessments occurred at baseline, 3 months (M3), and 6 months (M6). Adjusted linear mixed model analysis of variance determined intervention effects on walking self-efficacy, outcome expectations, goal setting, and perceived barrier interference at M3. Path analysis determined mediation of intervention effects on physical activity at M6 by changes in social cognitive constructs during the intervention (i.e., baseline to M3). BEAT Cancer significantly improved self-efficacy, goals, negative outcome expectations, and barriers. Total path analysis model explained 24 % of the variance in M6 physical activity. There were significant paths from randomized intervention group to self-efficacy (β = 0.15, p < .05) and barriers (β = -0.22, p < .01). Barriers demonstrated a borderline significant association with M6 physical activity (β = -0.24, p = .05). No statistically significant indirect effects were found. Although BEAT Cancer significantly improved social cognitive constructs, no significant indirect effects on physical activity improvements 3 months post-intervention were observed (NCT00929617).
Do attentional capacities and processing speed mediate the effect of age on executive functioning?
Gilsoul, Jessica; Simon, Jessica; Hogge, Michaël; Collette, Fabienne
2018-02-06
The executive processes are well known to decline with age, and similar data also exists for attentional capacities and processing speed. Therefore, we investigated whether these two last nonexecutive variables would mediate the effect of age on executive functions (inhibition, shifting, updating, and dual-task coordination). We administered a large battery of executive, attentional and processing speed tasks to 104 young and 71 older people, and we performed mediation analyses with variables showing a significant age effect. All executive and processing speed measures showed age-related effects while only the visual scanning task performance (selective attention) was explained by age when controlled for gender and educational level. Regarding mediation analyses, visual scanning partially mediated the age effect on updating while processing speed partially mediated the age effect on shifting, updating and dual-task coordination. In a more exploratory way, inhibition was also found to partially mediate the effect of age on the three other executive functions. Attention did not greatly influence executive functioning in aging while, in agreement with the literature, processing speed seems to be a major mediator of the age effect on these processes. Interestingly, the global pattern of results seems also to indicate an influence of inhibition but further studies are needed to confirm the role of that variable as a mediator and its relative importance by comparison with processing speed.
Social capital and health in China: exploring the mediating role of lifestyle.
Xue, Xindong; Cheng, Mingmei
2017-11-06
Although social capital as a key determinant of health has been well established in various studies, little is known about how lifestyle factors mediate this relationship. Understanding the cross-relationships between social capital, health, and lifestyle factors is important if health promotion policies are to be effective. The purpose of this study is to explore whether different dimensions of social capital and lifestyle factors are related, and whether lifestyle factors mediate the association between social capital and self-rated health (SRH) and psychological well-being (PWB) in China. This study used nationally representative data from the 2014 China Family Panel Studies (n = 28,916). The data reported on three dimensions of individual-level social capital: social trust, social relationship and Chinese Communist Party (CCP) membership. Health was assessed using SRH and PWB. Five lifestyle indicators were recorded: healthy diet, physical activity, smoking, sleeping, and non-overweight status. Logistic regression was used to examine the associations between social capital and lifestyle factors, and whether there was a mediating role of lifestyle. Odds ratios relating health status to social capital were reported before and after adjustment for lifestyle factors. Mediation analysis was then used to calculate the total, direct and indirect effects of social capital on SRH and PWB. The results show that social trust was significantly associated with all five lifestyle factors. Social relationship was significantly associated with four of the five: healthy diet, physical activity, sleeping and non-overweight. CCP membership was only significantly associated with two lifestyle factors: physical activity and non-overweight. Social trust and social relationship were significantly related to both SRH and PWB. CCP membership was only significantly related to SRH. Mediation analysis found modest evidence that lifestyle factors influenced the relationship between all three types of social capital and SRH. In contrast, only social trust and social relationship, but not CCP membership, were mediated by lifestyle factors with respect to PWB. This study is the first to explore the mediating role of lifestyle factors in the relationship between social capital and health in China. The overall findings suggest that lifestyle factors modestly mediate the association between social capital and health. The degree of mediating effect varies across different dimensions of social capital. Social capital-based health promotion policies would benefit from taking lifestyle factors into account.
Wachen, Jennifer Schuster; Shipherd, Jillian C; Suvak, Michael; Vogt, Dawne; King, Lynda A; King, Daniel W
2013-06-01
The mediating role of posttraumatic stress symptomatology (PSS) on the association between warzone exposure and physical health symptoms in 7 bodily systems (cardiovascular, dermatological, gastrointestinal, genitourinary, musculoskeletal, neurological, and pulmonary) was examined. We also examined if mediation effects varied as a function of sex. A sample of 317 U.S. Gulf war veterans was assessed for warzone exposure, PSS, and physical health symptoms 10 years after deployment. PSS was significantly associated with postdeployment physical health in all symptom categories when accounting for predeployment health (with effect sizes ranging from a 1.27-1.64 increase in the likelihood of postdeployment physical health symptoms with a 1 standard deviation increase in the PSS symptoms). PSS severity mediated the relationship between warzone exposure and postdeployment symptoms in all physical health domains (with percent mediation ranging 44%-75%). A significant Warzone Exposure × PSS interaction emerged for 5 outcomes such that the effect of PSS on physical health was stronger for veterans reporting lower warzone exposure. No significant interactions with sex emerged. These findings suggest the important influence of PSS on physical health symptoms for both men and women. Published 2013. This article is a US Government work and is in the public domain in the USA.
Stacey, F G; James, E L; Chapman, K; Lubans, D R
2016-04-14
Despite increasing numbers of cancer survivors and evidence that diet and physical activity improves the health of cancer survivors, most do not meet guidelines. Some social cognitive theory (SCT)-based interventions have increased physical activity behavior, however few have used objective physical activity measures. The Exercise and Nutrition Routine Improving Cancer Health (ENRICH) randomized controlled trial reported a significant intervention effect for the primary outcome of pedometer-assessed step counts at post-test (8-weeks) and follow-up (20-weeks). The aim of this study was to test whether the SCT constructs operationalized in the ENRICH intervention were mediators of physical activity behavior change. Randomized controlled trial with 174 cancer survivors and carers assessed at baseline, post-test (8-weeks), and follow-up (20-weeks). Participants were randomized to the ENRICH six session face-to-face healthy lifestyle program, or to a wait-list control. Hypothesized SCT mediators of physical activity behavior change (self-efficacy, behavioral goal, outcome expectations, impediments, and social expectations) were assessed using valid and reliable scales. Mediation was assessed using the Preacher and Hayes SPSS INDIRECT macro. At eight weeks, there was a significant intervention effect on behavioral goal (A = 9.12, p = 0.031) and outcome expectations (A = 0.25, p = 0.042). At 20 weeks, the intervention had a significant effect on self-efficacy (A = 0.31, p = 0.049) and behavioral goal (A = 13.15, p = 0.011). Only changes in social support were significantly associated with changes in step counts at eight weeks (B = 633.81, p = 0.023). Behavioral goal was the only SCT construct that had a significant mediating effect on step counts, and explained 22 % of the intervention effect at 20 weeks (AB = 397.9, 95 % CI 81.5-1025.5). SCT constructs had limited impact on objectively-assessed step counts in a multiple health behavior change intervention for cancer survivors and their carers. Behavioral goal measured post-intervention was a significant mediator of pedometer-assessed step counts at 3-months after intervention completion, and explained 22 % of the intervention effect. Future research should examine the separate impact of goals and planning, as well as examining mediators of behavior maintenance in physical activity interventions targeting cancer survivors. Australian and New Zealand Clinical Trials registry ANZCTRN1260901086257 .
He, Wu-Jing; Wong, Wan-Chi; Hui, Anna N-N
2017-01-01
This study examined the effect of music listening on creative thinking through the lens of the arousal-and-mood hypothesis, which posits that emotional reactions (i.e., arousal and valence) mediate the effect of music listening on cognitive functioning. Participants were randomly assigned to three groups: a positive music group ( n = 198), a negative music group ( n = 195), and a control group ( n = 191). Creative thinking and emotional reactions were assessed with the Test for Creative Thinking-Drawing Production and the Affect Grid, respectively. The results showed that both positively and negatively arousing music enhanced creative thinking. The results further revealed that arousal, regardless of valence, significantly mediated the music-creativity relationship. This study enriches the research on the arousal-and-mood hypothesis by (1) providing direct empirical testing on the mediating roles of emotional reactions; (2) including both positively and negatively arousing music in the study design; and (3) identifying that only arousal, and not valence, was a significant mediator in the music-creativity link.
He, Wu-Jing; Wong, Wan-Chi; Hui, Anna N.-N.
2017-01-01
This study examined the effect of music listening on creative thinking through the lens of the arousal-and-mood hypothesis, which posits that emotional reactions (i.e., arousal and valence) mediate the effect of music listening on cognitive functioning. Participants were randomly assigned to three groups: a positive music group (n = 198), a negative music group (n = 195), and a control group (n = 191). Creative thinking and emotional reactions were assessed with the Test for Creative Thinking-Drawing Production and the Affect Grid, respectively. The results showed that both positively and negatively arousing music enhanced creative thinking. The results further revealed that arousal, regardless of valence, significantly mediated the music-creativity relationship. This study enriches the research on the arousal-and-mood hypothesis by (1) providing direct empirical testing on the mediating roles of emotional reactions; (2) including both positively and negatively arousing music in the study design; and (3) identifying that only arousal, and not valence, was a significant mediator in the music-creativity link. PMID:29018395
Goedendorp, M M; Steverink, N
2017-09-01
Interventions based on self-management of well-being (SMW) theory have shown positive effects, but additional questions remain: (1) Are improvements in well-being, as induced by the interventions, mediated by improved self-management ability (SMA)? (2) Do the interventions show ceiling effects? (3) Is a particular format of SMW intervention (individual, group, or self-help) more effective? Data of three randomized controlled trials were pooled. The greater part of the sample (N = 445) consisted of single older females. A bootstrap analysis was performed to test for mediation. Regression analyses with interaction effects were performed to test for ceiling effects. Controlled and transformed effect sizes (proportion of maximum change) were calculated to compare formats. There was a full significant mediation of well-being by SMA. A significant interaction (ceiling) effect was found on well-being, but not on SMA. The controlled effect sizes of the raw scores were small to medium (.04-.49), and were small to large after transformation (.41-.73). None of the intervention formats was more effective. Support for SMW theory was found, i.e. increasing self-management ability lead to improved well-being. Some ceiling effect was found. We conclude that various SMW interventions formats can improve self-management abilities and well-being with medium effects.
Anxiety, affect, self-esteem, and stress: mediation and moderation effects on depression.
Nima, Ali Al; Rosenberg, Patricia; Archer, Trevor; Garcia, Danilo
2013-01-01
Mediation analysis investigates whether a variable (i.e., mediator) changes in regard to an independent variable, in turn, affecting a dependent variable. Moderation analysis, on the other hand, investigates whether the statistical interaction between independent variables predict a dependent variable. Although this difference between these two types of analysis is explicit in current literature, there is still confusion with regard to the mediating and moderating effects of different variables on depression. The purpose of this study was to assess the mediating and moderating effects of anxiety, stress, positive affect, and negative affect on depression. Two hundred and two university students (males = 93, females = 113) completed questionnaires assessing anxiety, stress, self-esteem, positive and negative affect, and depression. Mediation and moderation analyses were conducted using techniques based on standard multiple regression and hierarchical regression analyses. The results indicated that (i) anxiety partially mediated the effects of both stress and self-esteem upon depression, (ii) that stress partially mediated the effects of anxiety and positive affect upon depression, (iii) that stress completely mediated the effects of self-esteem on depression, and (iv) that there was a significant interaction between stress and negative affect, and between positive affect and negative affect upon depression. The study highlights different research questions that can be investigated depending on whether researchers decide to use the same variables as mediators and/or moderators.
Socioeconomic Attainment of Extremely Low Birth Weight Survivors: The Role of Early Cognition.
Dobson, Kathleen G; Ferro, Mark A; Boyle, Michael H; Schmidt, Louis A; Saigal, Saroj; Van Lieshout, Ryan J
2017-03-01
To determine: (1) if childhood cognitive and academic abilities mediate the association between being born at extremely low birth weight (ELBW) and socioeconomic attainment at age 29 to 36 years; (2) which cognitive abilities (IQ, verbal abilities, fluid intelligence, mathematical abilities, or academic achievement) most strongly mediate this association; and (3) if the mediating role of cognition is different in ELBW survivors with significant neurosensory impairment (NSI). A prospective, longitudinal cohort of 100 Canadian ELBW survivors born between 1977 and 1982 and 89 normal birth weight comparison participants were used to examine the mediating role of childhood cognition by using 5 cognitive mediators assessed at age 8 years (overall IQ, verbal IQ, performance IQ, quantitative ability, and academic achievement) on socioeconomic attainment at adulthood. Socioeconomic attainment was defined as personal annual earnings and full-time employment assessed via self-report at age 29 to 36 years. Mediation models revealed that childhood cognition mediated the association between ELBW status and income attainment, with mathematical abilities and overall IQ each accounting for 26% of the direct effect. Mediated effects were not statistically significant in full-time employment models. For both outcomes, the mediating effect of cognition was stronger for ELBW survivors with NSI. Childhood cognitive abilities partially mediate associations between ELBW status and adult income attainment. Early life cognition is a critical predictor of socioeconomic attainment in ELBW survivors, particularly in those born with NSI. Interventions aimed at enhancing early cognition in ELBW survivors may help optimize their later socioeconomic attainment. Copyright © 2017 by the American Academy of Pediatrics.
Révész, D; Verhoeven, J E; Milaneschi, Y; Penninx, B W J H
2016-08-01
Depressive and anxiety disorders are associated with shorter leukocyte telomere length (LTL), an indicator of cellular aging. It is, however, unknown which pathways underlie this association. This study examined the extent to which lifestyle factors and physiological changes such as inflammatory or metabolic alterations mediate the relationship. We applied mediation analysis techniques to data from 2750 participants of the Netherlands Study of Depression and Anxiety. LTL was assessed using quantitative polymerase chain reaction. Independent variables were current depressive (30-item Inventory of Depressive Symptoms - Self Report) and anxiety (21-item Beck's Anxiety Inventory) symptoms and presence of a depressive or anxiety disorder diagnosis based on DSM-IV; mediator variables included physiological stress systems, metabolic syndrome components and lifestyle factors. Short LTL was associated with higher symptom severity (B = -2.4, p = 0.002) and current psychiatric diagnosis (B = -63.3, p = 0.024). C-reactive protein, interleukin-6, waist circumference, triglycerides, high-density lipoprotein cholesterol and cigarette smoking were significant mediators in the relationship between psychopathology and LTL. When all significant mediators were included in one model, the effect sizes of the relationships between LTL and symptom severity and current diagnosis were reduced by 36.7 and 32.7%, respectively, and the remaining direct effects were no longer significant. Pro-inflammatory cytokines, metabolic alterations and cigarette smoking are important mediators of the association between depressive and anxiety disorders and LTL. This calls for future research on intervention programs that take into account lifestyle changes in mental health care settings.
USDA-ARS?s Scientific Manuscript database
To investigate the effects of patient health communication regarding their inflammatory bowel disease (IBD) to their health care providers and significant others in their daily life as a mediator in the relationship between gastrointestinal symptoms and gastrointestinal worry in pediatric patients. ...
Sun, Yi; Wu, Wei-Wen; Lin, Kuan-Chia; Chen, Jo-Lin
2016-10-01
Previous studies indicate that parents of developmentally delayed children have higher parenting stress (PS) and lower quality of life (QoL) than parents of healthy children. Parenting self-efficacy (PSE) may mediate the effects of PS on the QoL of parents. The present study explores the mediating role of PSE between PS and the QoL of parents of developmentally delayed children and compares the differences in several variables between fathers and mothers. A cross-sectional research design was used to study a sample of 70 parent dyads. Instruments used were the Basic Information Form, Parenting Stress Index Short Form (PSI-SF), Parenting Self-efficacy Scale (PSE Scale), and World Health Organization Quality of Life-BREF Taiwan version (WHOQOL-BREF). (1) Participants had a moderate level of QoL, PS, and PSE. (2) The PS of participants was significantly and negatively correlated with both QoL and PSE while their PSE was significantly and positively correlated with QoL. (3) The PSE of the fathers completely mediated the effects of PS on their QoL (p < .001), accounting for 62.2% of observed variation, while the PSE of the mothers partially mediated the effects of PS on their QoL (p < .05), accounting for 59.5% of observed variation. PSE was identified as the mediator between PS and QoL in both fathers and mothers. The PSE of the fathers completely mediated the effect of PS on QoL, while the PSE of the mothers partially mediated the effect of PS on QoL. Further research that explores the factors that affect the QoL of parents and then uses the results to develop interventions to enhance the PSE of parents, especially fathers, is recommended.
Müller, Rachel; Terrill, Alexandra L; Jensen, Mark P; Molton, Ivan R; Ravesloot, Craig; Ipsen, Catherine
2015-12-01
The aim of this study was to examine how the construct of happiness is related to pain intensity, pain interference, and distress in individuals with physical disabilities. This study involves cross-sectional analyses of 471 individuals with a variety of health conditions reporting at least mild pain. The first hypothesis that happiness mediates the relationship between pain intensity and two outcomes, pain interference and distress, was not supported. The second hypothesis was supported by a good fitting model (χ2(10) = 12.83, P = 0.23, root-mean-square error of approximation = 0.025) and indicated that pain intensity significantly mediated the effect of happiness on pain interference (indirect effect: β = -0.13, P < 0.001) and on distress (indirect effect: β = 0.10, P = 0.01). Happiness showed a significant direct effect on pain intensity (β = -0.20, P < 0.001). A third model exploring the happiness components meaning, pleasure, and engagement fitted well (χ2(4) = 9.65, P = 0.05, root-mean-square error of approximation = 0.055). Pain intensity acted as a significant mediator but only mediated the effect of meaning on pain interference (indirect effect: β = -0.07, P = 0.05) and on distress (indirect effect via pain interference: β = -0.04, P = 0.05). Only meaning (β = -0.10, P = 0.05), but neither pleasure nor engagement, had a significant direct effect on pain intensity. Participants who reported greater happiness reported lower pain interference and distress through happiness' effects on pain intensity. Experiencing meaning and purpose in life seems to be most closely (and negatively) associated with pain intensity, pain interference, and distress. Findings from this study can lay the groundwork for intervention studies to better understand how to more effectively decrease pain intensity, pain interference, and distress.
Long-term relations among prosocial-media use, empathy, and prosocial behavior.
Prot, Sara; Gentile, Douglas A; Anderson, Craig A; Suzuki, Kanae; Swing, Edward; Lim, Kam Ming; Horiuchi, Yukiko; Jelic, Margareta; Krahé, Barbara; Liuqing, Wei; Liau, Albert K; Khoo, Angeline; Petrescu, Poesis Diana; Sakamoto, Akira; Tajima, Sachi; Toma, Roxana Andreea; Warburton, Wayne; Zhang, Xuemin; Lam, Ben Chun Pan
2014-02-01
Despite recent growth of research on the effects of prosocial media, processes underlying these effects are not well understood. Two studies explored theoretically relevant mediators and moderators of the effects of prosocial media on helping. Study 1 examined associations among prosocial- and violent-media use, empathy, and helping in samples from seven countries. Prosocial-media use was positively associated with helping. This effect was mediated by empathy and was similar across cultures. Study 2 explored longitudinal relations among prosocial-video-game use, violent-video-game use, empathy, and helping in a large sample of Singaporean children and adolescents measured three times across 2 years. Path analyses showed significant longitudinal effects of prosocial- and violent-video-game use on prosocial behavior through empathy. Latent-growth-curve modeling for the 2-year period revealed that change in video-game use significantly affected change in helping, and that this relationship was mediated by change in empathy.
Doss, Brian D; Mitchell, Alexandra; Georgia, Emily J; Biesen, Judith N; Rowe, Lorelei Simpson
2015-04-01
Empirically based couple therapy results in significant improvements in relationship satisfaction for the average couple; however, further research is needed to identify mediators that lead to change and to ensure that improvements in mediators predict subsequent-not just concurrent-relationship satisfaction. In addition, given that much of the current literature on couple therapy examines outcomes in a research environment, it is important to examine mediators in a treatment-as-usual setting. To address these questions, 161 heterosexual couples (322 individuals) received treatment-as-usual couple therapy at one of two Veteran Administration Medical Centers (M = 5.0 and 13.0 sessions at the two sites) and were assessed before every session. The majority of couples were married (85%) and had been together for a median of 7.8 years (SD = 13). Participants were primarily White, non-Hispanic (69%), African American (21%), and White, Hispanic/Latino (8%). Individuals' own self-reported improvements in communication, emotional closeness, and psychological distress (but not frequency of behaviors targeted in treatment) mediated the effect of treatment on their subsequent relationship satisfaction. When all significant mediators were examined simultaneously, improvements in men's and women's emotional closeness and men's psychological distress independently mediated subsequent relationship satisfaction. In contrast, improvements in earlier relationship satisfaction mediated the effect of treatment only on subsequent psychological distress. This study identifies unique mediators of treatment effects and shows that gains in mechanisms predict subsequent relationship satisfaction. Future investigations should focus on the role of emotional closeness and psychological distress-constructs that have often been neglected-in couple therapy. (PsycINFO Database Record (c) 2015 APA, all rights reserved).
Organizational justice, psychological distress, and work engagement in Japanese workers.
Inoue, Akiomi; Kawakami, Norito; Ishizaki, Masao; Shimazu, Akihito; Tsuchiya, Masao; Tabata, Masaji; Akiyama, Miki; Kitazume, Akiko; Kuroda, Mitsuyo
2010-01-01
To investigate the cross-sectional association between organizational justice (i.e., procedural justice and interactional justice) and psychological distress or work engagement, as well as the mediating roles of other job stressors (i.e., job demands and job control, or their combination, effort-reward imbalance [ERI], and worksite support). A total of 243 workers (185 males and 58 females) from a manufacturing factory in Japan were surveyed using a self-administered questionnaire including the Organizational Justice Questionnaire, Job Content Questionnaire, Effort-Reward Imbalance Questionnaire, K6 scale, Utrecht Work Engagement Scale, and other covariates. Multiple mediation analyses with the bootstrap technique were conducted. In the bivariate analysis, procedural justice and interactional justice were significantly and negatively associated with psychological distress; they were significantly and positively associated with work engagement. In the mediation analysis, reward at work (or ERI) significantly mediated between procedural justice or interactional justice and psychological distress; worksite support significantly mediated between procedural justice or interactional justice and work engagement. The effects of organizational justice on psychological distress seem to be mediated by reward at work (or ERI) while those regarding work engagement may be mediated by worksite support to a large extent, at least in Japanese workers.
Emotional eating as a mediator between depression and weight gain.
van Strien, Tatjana; Konttinen, Hanna; Homberg, Judith R; Engels, Rutger C M E; Winkens, Laura H H
2016-05-01
Depression is often associated with weight gain but underlying mechanisms are unclear. This study assessed whether three psychological eating styles (emotional eating, external eating and restrained eating) act as mediators between depression and weight gain. We used structural equation modelling to test the hypothesized mediation models in a sample of 298 fathers and 294 mothers by assessing self-reported eating styles (Dutch Eating Behavior Questionnaire), depressive feelings (Depressive Mood List) and body mass index (BMI) at baseline and BMI after five years. In the model with emotional eating we also assessed the moderation effect of 5-HTTLPR genotype in a sub-sample of 520 Caucasians. All analyses were performed separately for the two sexes. Although the overall effect of depression on weight gain was statistically non-significant in both sexes, there was a causal chain between depression, emotional eating and weight gain in the mothers. Depressive symptoms were related to higher emotional eating and emotional eating predicted greater increases in BMI independently of depression. Moreover, the indirect effect (via emotional eating) of depression on BMI change was significant (Beta = 0.18, P = 0.026). This mediation effect was found to be independent of 5-HTTLPR genotype. No such mediation effect was found for the fathers. Further, external eating and restrained eating did not act as mediators between depression and weight gain in either sex. The finding that emotional eating acted as mediator between depression and weight gain in the mothers suggests that obesity interventions should take emotional eating into account. Copyright © 2016 Elsevier Ltd. All rights reserved.
Wu, Jiao; Wu, Yun-tao; Feng, Shu-xiu; Meng, Heng; Chen, Hui
2012-11-01
To understand the relationship between negative life events and suicide ideation, and how it was influenced by the mediating effect of depression. 1145 college students from one university were selected using cluster sampling. Both Symptom Check List (SCL-90) and Questionnaire were administered to measure depression and suicide ideation in the past week and on the prevalence of negative life events and related information. Recent negative life events would include physical illness, academic problem, financial problem and interpersonal conflict etc. Multiple logistic regressions were used to identify the mediating effect of depression. Physical illness (OR = 2.5, P = 0.028), interpersonal conflict (OR = 7.2, P = 0.002) and financial problem (OR = 1.6, P = 0.026) were significantly associated with suicide ideation, but academically-related problems did not seem to be significantly associated with suicide ideation (OR = 1.8, P = 0.090). After adjusted for depression, both physical illness and interpersonal conflicts were not but financial problem remained significantly associated with suicide ideation (OR = 1.7, P = 0.014). Our data showed that depression fully mediated the relationship between physical illness, interpersonal conflict and suicide ideation, but did not mediate the relationship between financial problem and suicide ideation. Depression played different mediating roles between different negative life events and suicide ideation. The findings from this study might be able to provide some clues for the prevention interventions on college students.
Kim, Song E.; Cho, Juhee; Kwon, Min-Jung; Chang, Yoosoo; Ryu, Seungho; Shin, Hocheol
2016-01-01
This study was designed to investigate associations among five factor personality traits, perceived stress, and depressive symptoms and to examine the roles of personality and perceived stress in the relationship between gender and depressive symptoms. The participants (N = 3,950) were part of a cohort study for health screening and examination at the Kangbuk Samsung Hospital. Personality was measured with the Revised NEO Personality Inventory (NEO-PI-R). Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (CES-D). Perceived stress level was evaluated with a self-reported stress questionnaire developed for the Korea National Health and Nutrition Examination Survey. A higher degree of neuroticism and lower degrees of extraversion, agreeableness, and conscientiousness were significantly associated with greater perceived stress and depressive symptoms. Neuroticism and extraversion had significant direct and indirect effects (via stress as a mediator) on depressive symptoms in both genders. Agreeableness and conscientiousness had indirect effects on depression symptoms in both genders. Multiple mediation models were used to examine the mediational roles of each personality factor and perceived stress in the link between gender and depressive symptoms. Four of the personality factors (except openness) were significant mediators, along with stress, on the relationship between gender and depressive symptoms. Our findings suggest that the links between personality factors and depressive symptoms are mediated by perceived stress. As such, personality is an important factor to consider when examining the link between gender and depression. PMID:27120051
Karnewar, Santosh; Vasamsetti, Sathish Babu; Gopoju, Raja; Kanugula, Anantha Koteswararao; Ganji, Sai Krishna; Prabhakar, Sripadi; Rangaraj, Nandini; Tupperwar, Nitin; Kumar, Jerald Mahesh; Kotamraju, Srigiridhar
2016-04-11
Mitochondria-targeted compounds are emerging as a new class of drugs that can potentially alter the pathophysiology of those diseases where mitochondrial dysfunction plays a critical role. We have synthesized a novel mitochondria-targeted esculetin (Mito-Esc) with an aim to investigate its effect during oxidative stress-induced endothelial cell death and angiotensin (Ang)-II-induced atherosclerosis in ApoE(-/-) mice. Mito-Esc but not natural esculetin treatment significantly inhibited H2O2- and Ang-II-induced cell death in human aortic endothelial cells by enhancing NO production via AMPK-mediated eNOS phosphorylation. While L-NAME (NOS inhibitor) significantly abrogated Mito-Esc-mediated protective effects, Compound c (inhibitor of AMPK) significantly decreased Mito-Esc-mediated increase in NO production. Notably, Mito-Esc promoted mitochondrial biogenesis by enhancing SIRT3 expression through AMPK activation; and restored H2O2-induced inhibition of mitochondrial respiration. siSIRT3 treatment not only completely reversed Mito-Esc-mediated mitochondrial biogenetic marker expressions but also caused endothelial cell death. Furthermore, Mito-Esc administration to ApoE(-/-) mice greatly alleviated Ang-II-induced atheromatous plaque formation, monocyte infiltration and serum pro-inflammatory cytokines levels. We conclude that Mito-Esc is preferentially taken up by the mitochondria and preserves endothelial cell survival during oxidative stress by modulating NO generation via AMPK. Also, Mito-Esc-induced SIRT3 plays a pivotal role in mediating mitochondrial biogenesis and perhaps contributes to its anti-atherogenic effects.
Tang, Catherine So-Kum; Wu, Anise M S
2010-12-01
A multiple mediation model was proposed to integrate core concepts of the social axioms framework and the social cognitive theory in order to understand gambling behavior. It was hypothesized that the influence of general fate control belief on problem gambling and negative mood would be mediated by gambling-specific beliefs. Data from 773 Chinese college recreational gamblers were collected. The bootstrapping procedure was used to test the multiple mediation hypotheses. Significant indirect effects of fate control belief on problem gambling and negative mood through two gambling-specific mediators were found. Gambling expectancy bias was a more salient mediator than gambling self-efficacy. Fate control belief was also found to have a significant direct effect on negative mood. In general, a high level of general fate control belief was related to greater gambling expectancy bias and lower self-efficacy in resisting gambling, which were in turn related to problem gambling and negative mood. Limitations and implications of the study were discussed.
Marino, Luise V; Pathan, Nazima; Meyer, Rosan W; Wright, Victoria J; Habibi, Parviz
2016-03-01
Glutamine has been shown to promote the release of heat shock protein 70 (HSP70) both within experimental in vitro models of sepsis and in adults with septic shock. This study aimed to investigate the effects of 2 mM glutamine and an inhibitor of HSP70 (KNK437) on the release of HSP70 and inflammatory mediators in healthy adult volunteers. An in vitro whole blood endotoxin stimulation assay was used. The addition of 2 mM glutamine significantly increased HSP70 levels over time (P < 0.05). HSP70 release had a positive correlation at 4 h with IL-1 β (r = 0.51, P = 0.03) and an inverse correlation with TNF-α (r = -0.56, P = 0.02) and IL-8 levels (r = -0.52, P = 0.03), and there were no significant correlations between HSP70 and IL6 or IL-10 or glutamine. Glutamine supplementation significantly (P < 0.05) attenuated the release of IL-10 at 4 h and IL-8 at 24 h, compared with conditions without glutamine. In endotoxin-stimulated blood there were no significant differences in the release of IL-6, TNF-α, and IL-1 β with glutamine supplementation at 4 and 24 h. However, glutamine supplementation (2 mM) appeared to attenuate the release of inflammatory mediators (IL-1 β, IL-6, TNF-α), although this effect was not statistically significant. The addition of KNK437, a HSP70 inhibitor, significantly diminished HSP70 release, which resulted in lower levels of inflammatory mediators (P < 0.05). Glutamine supplementation promotes HSP70 release in an experimental model of sepsis. After the addition of KNK437, the effects of glutamine on HSP70 and inflammatory mediator release appear to be lost, suggesting that HSP70 in part orchestrates the inflammatory mediator response to sepsis. The clinical implications require further investigation. Copyright © 2016 Elsevier Inc. All rights reserved.
Ávila, Rafaela T; de Paula, Jonas J; Bicalho, Maria A; Moraes, Edgar N; Nicolato, Rodrigo; Malloy-Diniz, Leandro F; Diniz, Breno S
2015-05-01
Previous studies suggest that executive functions influence the performance on visuoconstructional tasks. This study aims to investigate whether the relationship between planning ability and the copy of complex figures is mediated by distinct components of executive functions (i.e., working memory, inhibitory control and cognitive flexibility). We included a 129 older adults with Alzheimer's disease (n=36, AD), mild cognitive impairment (MCI, n=67), and with no evidence of cognitive impairment (controls, n=26). We evaluated the mediation effect of planning abilities, working memory, cognitive flexibility and inhibitory control on visuoconstructional tasks using a multiple mediation models. We found a significant direct effect of planning on visuoconstructional abilities and a partial mediation effect of working memory and cognitive flexibility on visuoconstructional abilities. The present results indicate that the performance on visuoconstructional task is mediated by multiple interrelated executive functions components, in particular working memory and cognitive flexibility.
O'Shea, D M; Dotson, V M; Fieo, R A
2017-12-01
Personality traits have been shown to be predictors of depressive symptoms in late life. Thus, we examined whether other more modifiable sources of individual differences such as self-efficacy and self-perceptions of aging would mediate the association between personality traits and depressive symptoms in older adults. Data were obtained from 3,507 older adult participants who took part in the 2012 Health and Retirement Study. The "Big Five" personality traits, self-efficacy, aging perceptions, and depressive symptoms were assessed. Mediation analyses tested the hypothesis that self-efficacy and aging perceptions would mediate the relationship between personality traits and depressive symptoms. All five personality traits were significant predictors of depressive symptoms. Neuroticism was positively associated with depressive symptoms and had the greatest effect compared with the other personality traits. There was a significant indirect effect of neuroticism, extraversion, and conscientiousness on depressive symptoms (including both mediators). The mediating effect of aging perceptions on the relationship between neuroticism and depressive symptoms was the strongest compared with self-efficacy, accounting for approximately 80% of the total indirect effect. Our results provide support for interventions aimed at improving self-perceptions related to efficacy and aging in order to reduce depressive symptoms in older adults. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Zhou, Yangen; Lu, Jiamei; Liu, Xianmin; Zhang, Pengcheng; Chen, Wuying
2014-01-01
To explore the impact of Core self-evaluations on job burnout of nurses, and especially to test and verify the mediator role of organizational commitment between the two variables. Random cluster sampling was used to pick up participants sample, which consisted of 445 nurses of a hospital in Shanghai. Core self-evaluations questionnaire, job burnout scale and organizational commitment scale were administrated to the study participants. There are significant relationships between Core self-evaluations and dimensions of job burnout and organizational commitment. There is a significant mediation effect of organizational commitment between Core self-evaluations and job burnout. To enhance nurses' Core self-evaluations can reduce the incidence of job burnout.
Hopwood, C J; Ansell, E B; Fehon, D C; Grilo, C M
2011-03-01
Childhood maltreatment is a risk factor for eating disorder and negative/depressive affect appears to mediate this relation. However, the specific elements of eating- and body-related psychopathology that are influenced by various forms of childhood maltreatment remain unclear, and investigations among adolescents and men/boys have been limited. This study investigated the mediating role of negative affect/depression across multiple types of childhood maltreatment and eating disorder features in hospitalized adolescent boys and girls. Participants were 148 adolescent psychiatric inpatients who completed an assessment battery including measures of specific forms of childhood maltreatment (sexual, emotional, and physical abuse), negative/depressive affect, and eating disorder features (dietary restriction, binge eating, and body dissatisfaction). Findings suggest that for girls, negative/depressive affect significantly mediates the relationships between childhood maltreatment and eating disorder psychopathology, although effects varied somewhat across types of maltreatment and eating disorder features. Generalization of mediation effects to boys was limited.
2012-01-01
Background Important health benefits can be achieved when physical activity in children from low socio-economic status is promoted and sedentariness is limited. By specifying the mediating mechanisms of existing interventions one can improve future physical activity interventions. This study explored potential mediators of the long-term effect of the school-based multicomponent JUMP-in intervention on sport participation, outdoor play and screen time in Dutch primary schoolchildren from disadvantaged neighborhoods. Methods In total, 600 primary schoolchildren (aged 9.8 ± 0.7, 51% girls, 13% Dutch ethnicity, 35% overweight) from 9 intervention and 10 control schools were included in the analyses. JUMP-in was developed using Intervention Mapping, and targeted psychological and environmental determinants of physical activity. Outcome behaviors were self-reported sport participation, outdoor play, TV-viewing behavior and computer use. Potential mediators were self-reported psychological, social and physical environmental factors. Results JUMP-in was effective in improving sport participation after 20 months, but not in improving outdoor play, or reducing TV-viewing or computer time. JUMP-in was not effective in changing hypothesized mediators so no significant mediated effects could be identified. However, changes in self-efficacy, social support and habit strength were positively associated with changes in sport participation, and changes in social support, self-efficacy, perceived planning skills, enjoyment and habit strength were positively associated with changes in outdoor play. Changes in enjoyment was positively associated with changes in TV-viewing while parental rules were negatively associated. Having a computer in the bedroom and enjoyment were positively associated with changes in computer use, while changes in parental rules were negatively associated. Conclusions Besides a significant positive effect on sports participation, no significant intervention effect on outdoor play, screen time or any of the potential mediators was found. This suggest that other (unmeasured) factors operated as mediating mechanisms of the intervention, that we used unsuccessful intervention strategies, that the strategies were inappropriately implemented, or that children are unable to accurately recall past activities and cognitions. Additionally, the school setting might not be the sole channel to influence leisure time activities. Still, several personal and environmental constructs were found to be relevant in predicting change in sport participation, outdoor play and screen behavior and seem to be potential mediators. Future interventions are recommended including more effective strategies targeting these relevant constructs, addressing different constructs (e.g. pedagogic skills of parents), and focusing on different implementation settings. Trail registration ISRCTN17489378 PMID:23130806
Kan, Chiemi; Kawakami, Norito; Umeda, Maki
2015-12-01
The majority of studies on the role of psychological resources linking childhood socioeconomic status (SES) and adult health have been conducted in Western countries. Empirical evidence for mediation effects of psychological resources is currently lacking in Japan. The purpose of this study was to investigate the mediating effect of psychological resources (mastery and sense of coherence [SOC]) on the association between childhood SES and current health. Analyses were conducted on cross-sectional data (1,497 men and 1,764 women) from the Japanese Study of Stratification, Health, Income, and Neighborhood Study (J-SHINE) in Tokyo. Psychological resources (mastery and SOC), childhood SES (parents' education and perceived childhood SES), and current health of adults (psychological distress measured by K6 and self-rated health) were measured using a self-report questionnaire. Mastery and SOC significantly and independently mediated the association between childhood SES and current health in the total sample after adjusting for age, gender, and respondent education, regardless of type of SES or health outcome indicators. Similar mediation effects were observed for both men and women. A few gender differences were observed; specifically, SOC significantly mediated the association between parents' education and current health only among women, and it mediated the association between perceived childhood SES and current health only among men. Overall, the findings underscore the importance of the mediating role of psychological resources in the association between childhood SES and current health.
Østefjells, T; Lystad, J U; Berg, A O; Hagen, R; Loewy, R; Sandvik, L; Melle, I; Røssberg, J I
2017-10-01
Early trauma is linked to higher symptom levels in bipolar and psychotic disorders, but the translating mechanisms are not well understood. This study examines whether the relationship between early emotional abuse and depressive symptoms is mediated by metacognitive beliefs about thoughts being uncontrollable/dangerous, and whether this pathway extends to influence positive symptoms. Patients (N = 261) with psychotic or bipolar disorders were assessed for early trauma experiences, metacognitive beliefs, and current depression/anxiety and positive symptoms. Mediation path analyses using ordinary least-squares regressions tested if the effect of early emotional abuse on depression/anxiety was mediated by metacognitive beliefs, and if the effect of early emotional abuse on positive symptoms was mediated by metacognitive beliefs and depression/anxiety. Metacognitive beliefs about thoughts being uncontrollable/dangerous significantly mediated the relationship between early emotional abuse and depression/anxiety. Metacognitive beliefs and depression/anxiety significantly mediated the relationship between early emotional abuse and positive symptoms. The models explained a moderate amount of the variance in symptoms (R 2 = 0.21-0.29). Our results indicate that early emotional abuse is relevant to depression/anxiety and positive symptoms in bipolar and psychotic disorders, and suggest that metacognitive beliefs could play a role in an affective pathway to psychosis. Metacognitive beliefs could be relevant treatment targets with regards to depression/anxiety and positive symptoms in bipolar and psychotic disorders.
Chae, Su Jin; Jeong, So Mi; Chung, Yoon-Sok
2017-09-01
This study is aimed at identifying the relationships between medical school students' academic burnout, empathy, and calling, and determining whether their calling has a mediating effect on the relationship between academic burnout and empathy. A mixed method study was conducted. One hundred twenty-seven medical students completed a survey. Scales measuring academic burnout, medical students' empathy, and calling were utilized. For statistical analysis, correlation analysis, descriptive statistics analysis, and hierarchical multiple regression analyses were conducted. For qualitative approach, eight medical students participated in a focus group interview. The study found that empathy has a statistically significant, negative correlation with academic burnout, while having a significant, positive correlation with calling. Sense of calling proved to be an effective mediator of the relationship between academic burnout and empathy. This result demonstrates that calling is a key variable that mediates the relationship between medical students' academic burnout and empathy. As such, this study provides baseline data for an education that could improve medical students' empathy skills.
Rose, John; Nelson, Lisa; Hardiman, Rebecca
2016-11-01
Cognitions are starting to receive more prominence as important when examining a number of factors including the topography of challenging behaviour. This study examined the relationships between maternal stress, challenging behaviour (aggressive and self-injurious behaviours) and parental cognitions and specifically whether maternal cognitions mediated the effect of challenging behaviour on parenting stress. 46 mothers of children and young adults with ID completed questionnaires regarding their child's challenging behaviour, maternal cognitions and stress. Significant correlations were found between challenging behaviour and maternal stress. The overall mediation models for aggression and self-injurious behaviour were significant. The Challenging Behaviour Perception Questionnaire: Consequences client subscale was the only independent significant mediator for both behaviours. Cognitions do play an important part in mediating the relationship between challenging behaviour and stress. Further research is needed to examine the similarities and differences between the mediation models for aggression and self-injurious behaviour.
Wang, Junping; Qin, Wen; Liu, Feng; Liu, Bing; Zhou, Yuan; Jiang, Tianzi; Yu, Chunshui
2016-07-01
Microsatellite variants in the arginine vasopressin receptor 1A gene (AVPR1A) RS3 have been associated with normal social behaviors variation and autism spectrum disorders (ASDs) in a sex-specific manner. However, neural mechanisms underlying these associations remain largely unknown. We hypothesized that AVPR1A RS3 variants affect altruistic behavior by modulating the gray matter volume (GMV) of specific brain regions in a sex-specific manner. We investigated 278 young healthy adults using the Dictator Game to assess altruistic behavior. All subjects were genotyped and main effect of AVPR1A RS3 repeat polymorphisms and interaction of genotype-by-sex on the GMV were assessed in a voxel-wise manner. We observed that male subjects with relatively short repeats allocated less money to others and exhibited a significantly smaller GMV in the right fusiform face area (FFA) compared with male long homozygotes. In male subjects, the GMV of the right FFA exhibited a significant positive correlation with altruistic behavior. A mixed mediation and moderation analysis further revealed both a significant mediation effect of the GMV of the right FFA on the association between AVPR1A RS3 repeat polymorphisms and allocation sums and a significant moderation effect of sex (only in males) on the mediation effect. Post hoc analysis showed that the GMV of the right FFA was significantly smaller in male subjects carrying allele 426 than in non-426 carriers. These results suggest that the GMV of the right FFA may be a potential mediator whereby the genetic variants in AVPR1A RS3 affect altruistic behavior in healthy male subjects. Hum Brain Mapp 37:2700-2709, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Turiano, Nicholas A.; Hill, Patrick L.; Roberts, Brent W.; Spiro, Avron; Mroczek, Daniel K.
2013-01-01
This study examined the relationship between conscientiousness and mortality over 18 years and whether smoking behavior mediated this relationship. We utilized data from the Veterans Affairs Normative Aging Study on 1349 men who completed the Goldberg (1992) adjectival markers of the Big Five. Over the 18-year follow-up, 547 (41%) participants died. Through proportional hazards modeling in a structural equation modeling framework, we found that higher levels of conscientiousness significantly predicted longer life, and that this effect was mediated by current smoking status at baseline. Methodologically, we also demonstrate the effectiveness of using a structural equation modeling framework to evaluate mediation when using a censored outcome such as mortality. PMID:23504043
When mothers have serious mental health problems: parenting as a proximal mediator.
Oyserman, Daphna; Bybee, Deborah; Mowbray, Carol; Hart-Johnson, Tamera
2005-08-01
Maternal mental health (MMH) problems are associated with lack of confidence in one's parenting, overly lax or too harsh discipline, and child academic underperformance. We asked if parenting mediates the effect of MMH problems on academic outcomes even among mothers with serious mental illness (n=164). Structural equation analyses show a significant association between MMH problems and permissive (lack of parenting confidence, lack of follow through) parenting and verbal hostility as well as worse academic outcomes (school recorded grades, teacher reported behaviour). Permissive parenting completely mediated the direct effect of MMH on academic outcomes. Further analyses showed that the mediation effect was attributed to a single component of permissive parenting-lack of parenting confidence.
Madon, Stephanie; Guyll, Max; Buller, Ashley A.; Scherr, Kyle C.; Willard, Jennifer; Spoth, Richard
2010-01-01
This research examined whether self-fulfilling prophecy effects are mediated by self-verification, informational conformity, and modeling processes. The authors examined these mediational processes across multiple time frames with longitudinal data obtained from two samples of mother – child dyads (N1 = 487; N2 = 287). Children’s alcohol use was the outcome variable. The results provided consistent support for the mediational process of self-verification. In both samples and across several years of adolescence, there was a significant indirect effect of mothers’ beliefs on children’s alcohol use through children’s self-assessed likelihood of drinking alcohol in the future. Comparatively less support was found for informational conformity and modeling processes as mediators of mothers’ self-fulfilling effects. The potential for self-fulfilling prophecies to produce long lasting changes in targets’ behavior via self-verification processes are discussed. PMID:18665708
Madon, Stephanie; Guyll, Max; Buller, Ashley A; Scherr, Kyle C; Willard, Jennifer; Spoth, Richard
2008-08-01
This research examined whether self-fulfilling prophecy effects are mediated by self-verification, informational conformity, and modeling processes. The authors examined these mediational processes across multiple time frames with longitudinal data obtained from two samples of mother-child dyads (N-sub-1 = 486; N-sub-2 = 287), with children's alcohol use as the outcome variable. The results provided consistent support for the mediational process of self-verification. In both samples and across several years of adolescence, there was a significant indirect effect of mothers' beliefs on children's alcohol use through children's self-assessed likelihood of drinking alcohol in the future. Comparatively less support was found for informational conformity and modeling processes as mediators of mothers' self-fulfilling effects. The potential for self-fulfilling prophecies to produce long-lasting changes in targets' behavior via self-verification processes are discussed. (c) 2008 APA, all rights reserved
Prevention System Mediation of Communities That Care Effects on Youth Outcomes
Hawkins, J. David; Rhew, Isaac C.; Shapiro, Valerie B.; Abbott, Robert D.; Oesterle, Sabrina; Arthur, Michael W.; Briney, John S.; Catalano, Richard F.
2013-01-01
This study examined whether the significant intervention effects of the Communities That Care (CTC) prevention system on youth problem behaviors observed in a panel of eighth-grade students (Hawkins et al. Archives of Pediatrics and Adolescent Medicine 163:789–798 2009) were mediated by community-level prevention system constructs posited in the CTC theory of change. Potential prevention system constructs included the community’s degree of (a) adoption of a science-based approach to prevention, (b) collaboration on prevention activities, (c) support for prevention, and (d) norms against adolescent drug use as reported by key community leaders in 24 communities. Higher levels of community adoption of a science-based approach to prevention and support for prevention in 2004 predicted significantly lower levels of youth problem behaviors in 2007, and higher levels of community norms against adolescent drug use predicted lower levels of youth drug use in 2007. Effects of the CTC intervention on youth problem behaviors by the end of eighth grade were mediated fully by community adoption of a science-based approach to prevention. No other significant mediated effects were found. Results support CTC’s theory of change that encourages communities to adopt a science- based approach to prevention as a primary mechanism for improving youth outcomes. PMID:23828448
Lorenz, Mario; Rauhut, Franziska; Hofer, Christine; Gwosc, Stefanie; Müller, Eda; Praeger, Damaris; Zimmermann, Benno F; Wernecke, Klaus-Dieter; Baumann, Gert; Stangl, Karl; Stangl, Verena
2017-05-23
Consumption of tea is inversely associated with cardiovascular diseases. However, the active compound(s) responsible for the protective effects of tea are unknown. Although many favorable cardiovascular effects in vitro are mediated by epigallocatechin gallate (EGCG), its contribution to the beneficial effects of tea in vivo remains unresolved. In a randomised crossover study, a single dose of 200 mg EGCG was applied in three different formulas (as green tea beverage, green tea extract (GTE), and isolated EGCG) to 50 healthy men. Flow-mediated dilation (FMD) and endothelial-independent nitro-mediated dilation (NMD) was measured before and two hours after ingestion. Plasma levels of tea compounds were determined after each intervention and correlated with FMD. FMD significantly improved after consumption of green tea containing 200 mg EGCG (p < 0.01). However, GTE and EGCG had no significant effect on FMD. NMD did not significantly differ between interventions. EGCG plasma levels were highest after administration of EGCG and lowest after consumption of green tea. Plasma levels of caffeine increased after green tea consumption. The results show that EGCG is most likely not involved in improvement of flow-mediated dilation by green tea. Instead, other tea compounds, metabolites or combinations thereof may play a role.
Foshee, Vangie A; Benefield, Thad; Chen, May S; Reyes, Luz McNaughton; Dixon, Kimberly S; Ennett, Susan T; Moracco, Kathryn E; Bowling, J Michael
2016-04-01
Moms and Teens for Safe Dates (MTSD) is a dating abuse (DA) prevention program for teens exposed to domestic violence. In a randomized controlled trial (RCT), MTSD prevented certain types of DA victimization (psychological and physical) and perpetration (psychological and cyber) among teens with higher, but not lower, exposure to domestic violence. We built on these findings by using moderated mediation analysis to examine whether level of teen exposure to domestic violence conditioned the indirect effects of MTSD on these types of DA through targeted mediators. MTSD consisted of six mailed activity booklets. Mothers who had been former victims of domestic violence delivered the program to their teens. Mother and teen pairs were recruited into the RCT through community advertising and completed baseline and 6-month follow-up interviews (N = 277 pairs). As expected, MTSD had significant favorable effects for teens with higher but not lower exposure to domestic violence on several mediators that guided program content, including teen conflict management skills and mother-perceived severity of DA, self-efficacy for enacting DA prevention efforts, and comfort in communicating with her teen. MTSD had significant main effects on other mediators including teen feeling of family closeness and cohesion and mother-perceived susceptibility of her teen to DA. As expected, all significant indirect effects of MTSD on DA outcomes through mediators were for teens with higher exposure to domestic violence. Findings have implications for developing DA victimization and perpetration prevention programs for teens with high exposure to domestic violence.
Toughan, Hosam; Khalil, Samah R; El-Ghoneimy, Ashraf Ahmed; Awad, Ashraf; Seddek, A Sh
2018-03-01
The present study evaluated the potential modulatory effect(s) of dietary supplementation with Spirulina platensis (SP) on Atrazine (ATZ)-induced oxidative stress and inflammation in common carp (Cyprinus carpio L.). Common carp was exposed to ATZ (428μg/L) and SP (1%), either alone or in combination, for 40 days. Subsequently, the treatment groups were evaluated for ATZ-induced oxidative stress-mediated hepatic damage and the potential antioxidant effect(s) of SP supplementation. The results indicated that ATZ exposure led to a significant increase in the oxidative stress as suggested by the increased levels of lipid and DNA oxidative damage markers and the significant decline of antioxidant status biomarkers. Further, a real-time PCR analysis of the liver tissues revealed that the ATZ exposure resulted in the significant modulation of the mRNA expression of cytokines involved in the inflammatory response pathway in the liver, such as Interleukin (IL)-1ß and IL-10. The expression of IL-1ß mRNA was up-regulated while that of IL-10 mRNA was down-regulated. The group subjected to supplementation with SP exhibited a significant decrease in ATZ-induced oxidative stress-mediated hepatotoxic and inflammatory responses; however, these did not attain the levels of the control group. Owing to its ability for protecting against ATZ-induced oxidative stress-mediated hepatic damage in carps, SP could be a potentially effective and promising candidate as a feed additive for carps in aquaculture. Copyright © 2017 Elsevier Inc. All rights reserved.
Anxiety, Affect, Self-Esteem, and Stress: Mediation and Moderation Effects on Depression
Nima, Ali Al; Rosenberg, Patricia; Archer, Trevor; Garcia, Danilo
2013-01-01
Background Mediation analysis investigates whether a variable (i.e., mediator) changes in regard to an independent variable, in turn, affecting a dependent variable. Moderation analysis, on the other hand, investigates whether the statistical interaction between independent variables predict a dependent variable. Although this difference between these two types of analysis is explicit in current literature, there is still confusion with regard to the mediating and moderating effects of different variables on depression. The purpose of this study was to assess the mediating and moderating effects of anxiety, stress, positive affect, and negative affect on depression. Methods Two hundred and two university students (males = 93, females = 113) completed questionnaires assessing anxiety, stress, self-esteem, positive and negative affect, and depression. Mediation and moderation analyses were conducted using techniques based on standard multiple regression and hierarchical regression analyses. Main Findings The results indicated that (i) anxiety partially mediated the effects of both stress and self-esteem upon depression, (ii) that stress partially mediated the effects of anxiety and positive affect upon depression, (iii) that stress completely mediated the effects of self-esteem on depression, and (iv) that there was a significant interaction between stress and negative affect, and between positive affect and negative affect upon depression. Conclusion The study highlights different research questions that can be investigated depending on whether researchers decide to use the same variables as mediators and/or moderators. PMID:24039896
Kong, Feng; Zhao, Jingjing; You, Xuqun
2012-01-01
Over the past decade, emotional intelligence (EI) has received much attention in the literature. Previous studies indicated that higher trait or ability EI was associated with greater mental distress. The present study focused on mediating effects of positive and negative affect on the association between trait EI and mental distress in a sample of Chinese adults. The participants were 726 Chinese adults (384 females) with an age range of 18-60 years. Data were collected by using the Wong Law Emotional Intelligence Scale, the Positive Affect and Negative Affect Scale, and the General Health Questionnaire. Hierarchical regression analysis showed that EI was a significant predictor of positive affect, negative affect and mental distress. Further mediation analysis showed that positive and negative affect acted as partial mediators of the relationship between EI and mental distress. Furthermore, effect contrasts showed that there was no significant difference between the specific indirect effects through positive affect and through negative affect. This result indicated that positive affect and negative affect played an equally important function in the association between EI and distress. The significance and limitations of the results are discussed.
Collier, Kevin M; Coyne, Sarah M; Rasmussen, Eric E; Hawkins, Alan J; Padilla-Walker, Laura M; Erickson, Sage E; Memmott-Elison, Madison K
2016-05-01
The current study examined how parental mediation of media (restrictive mediation, active mediation, and coviewing) influenced child outcomes. Three meta-analyses, 1 for each type of mediation, were conducted on a total of 57 studies. Each analysis assessed the effectiveness of parental mediation on 4 pertinent child outcomes: media use, aggression, substance use, and sexual behavior. The overall results indicated small, but significant relationships between child outcomes and restrictive mediation (r+ = -.06), and coviewing (r+ = .09). Overall active mediation was nonsignificant, though active mediation was individually related to lower levels of aggression (r+ = -.08), sexual behavior (r+ = -.06), and substance use (r+ = -.11). This analysis revealed that parents may have the ability to mitigate some of the adverse effects of the media by using certain mediation strategies. Overall, a cooperative effort from the communication and parenting fields is necessary for a comprehensive analysis of parental mediation as well as a disentanglement of the various parental mediation measures. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Bugge, Ingrid; Dyb, Grete; Stensland, Synne Øien; Ekeberg, Øivind; Wentzel-Larsen, Tore; Diseth, Trond H
2017-06-01
Physically injured trauma survivors have particularly high risk for later somatic complaints and posttraumatic stress symptoms (PTSS). However, the potential mediating role of PTSS linking injury to later somatic complaints has been poorly investigated. In this study, survivors (N = 255) were interviewed longitudinally at 2 timepoints after the terror attack on Utøya Island, Norway, in 2011. Assessments included injury sustained during the attack, PTSS (after 4-5 months), somatic complaints (after 14-15 months), and background factors. Causal mediation analysis was conducted to evaluate the potential mediating role of PTSS in linking injury to somatic complaints comparing 2 groups of injured survivors with noninjured survivors. For the nonhospitalized injured versus the noninjured survivors, the mediated pathway was significant (average causal mediation effect; ACME = 0.09, p = .028, proportion = 55.8%). For the hospitalized versus the noninjured survivors, the mediated pathway was not significant (ACME = 0.04, p = .453, proportion = 11.6%). PTSS may play a significant mediating role in the development of somatic complaints among nonhospitalized injured trauma survivors. Intervening health professionals should be aware of this possible pathway to somatic complaints. Copyright © 2017 International Society for Traumatic Stress Studies.
Caricati, Luca; Mancini, Tiziana; Marletta, Giuseppe
2017-01-01
This research investigated the relationship among perception of ingroup threats (realistic and symbolic), conservative ideologies (social dominance orientation [SDO] and right-wing authoritarianism [RWA]), and prejudice against immigrants. Data were collected with a cross-sectional design in two samples: non-student Italian adults (n = 223) and healthcare professionals (n = 679). Results were similar in both samples and indicated that symbolic and realistic threats, as well as SDO and RWA, positively and significantly predicted anti-immigrant prejudice. Moreover, the model considering SDO and RWA as mediators of threats' effects on prejudice showed a better fit than the model in which ingroup threats mediated the effects of SDO and RWA on prejudice against immigrants. Accordingly, SDO and RWA partially mediated the effect of both symbolic and realistic threats, which maintained a significant effect on prejudice against immigrants, however.
Campaert, Kristel; Nocentini, Annalaura; Menesini, Ersilia
2017-09-01
Teachers respond differently to bullying and victimization. Socio-cognitive and moral domain theory suggest that students process teachers' behavior cognitively and that teachers' responses to incidents of bullying and victimization could affect students' level of moral disengagement. We examined the mediating effect of students' moral disengagement between types of teachers' responses to situations of bullying and victimization and individual bullying using multilevel mediation modelling. Participants were 609 students (50% boys, age M = 11.47, SD = 1.14) of central Italy, nested in 34 classes. Students rated the frequency of self-reported bullying and of teachers' responses to incidents of bullying and victimization on a 5-point Likert scale. Teachers' responses to bullying included non-intervention, mediation, group discussion, and sanctions. Teachers' responses to victimization included non-intervention, mediation, group discussion, and victim support. Results indicated that in the teachers' responses to incidents of bullying model, a significant indirect effect of non-intervention (β = .03; 95%CI [.01, .05]) and of sanctions (β = -.02; 95%CI [-.04, -.01]) on bullying through moral disengagement was found at the individual level. Similarly, in the model on teachers' responses toward victims there was a significant indirect effect through moral disengagement of non-intervention (β = .03; 95%CI [.02, .04]) and victim support (β = -.01; 95%CI [-.02, -.001]). At the class level there were no significant indirect effects. In sum, results indicated that moral disengagement is an important mediator at the individual level and suggest including teachers in anti-bullying interventions with a specific focus on their role for moral development. © 2017 Wiley Periodicals, Inc.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schmidt, Martina E., E-mail: m.schmidt@dkfz.de; Meynköhn, Anna; Habermann, Nina
Purpose: To explore the mediating role of inflammatory parameters in the development of fatigue, pain, and potentially related depressive symptoms during radiation therapy for breast cancer and its mitigation by resistance exercise. Methods and Materials: Breast cancer patients scheduled for adjuvant radiation therapy were randomized to 12-week progressive resistance exercise training (EX) or a relaxation control group. Interleukin-6 (IL-6) and interleukin-1 receptor antagonist (IL-1ra) were measured in serum samples collected before, at the end, and 6 weeks after radiation therapy from 103 chemotherapy-naïve participants. Fatigue was assessed with the multidimensional Fatigue Assessment Questionnaire, pain with the European Organization for Research andmore » Treatment of Cancer QLQ-C30, and depressive symptoms with the Center for Epidemiologic Studies Depression Scale. Analysis of covariance models, partial correlations, Freedman-Schatzkin tests, and R{sup 2} effect-size measures for mediation were calculated. Results: The analysis of covariance models revealed a significant intervention effect on IL-6 (P=.010) and the IL-6/IL-1ra ratio (P=.018), characterized by a marked increase during radiation therapy among controls, but no significant change in EX. Interleukin-1 receptor antagonist did not change significantly in either group (P=.88). Increased IL-6 and IL-6/IL-1ra levels at the end of radiation therapy were significantly associated with increased physical fatigue and pain 6 weeks after radiation. We observed significant partial mediation by IL-6 and IL-6/IL-1ra of the effect of resistance exercise on physical fatigue (Freedman-Schatzkin P=.023 and P<.001) and pain (both P<.001). Hereby IL-6 and IL-6/IL-1ra mediated between 15% and 24% of the variance of physical fatigue and pain explained by the intervention. Conclusions: This randomized, controlled trial showed a significantly increased proinflammatory cytokine level after adjuvant radiation therapy in breast cancer patients. This effect was counteracted by progressive resistance exercise training. Interleukin-6 and the IL-6/IL-1ra ratio seemed to mediate the beneficial effect of exercise on physical fatigue and pain but only to a small extent.« less
Iwanaga, Kanako; Chan, Fong; Tansey, Timothy N; Strauser, David; Ritter, Ellen; Bishop, Malachy; Brooks, Jessica
2018-05-30
Purpose Working alliance is one of the most important common factors for successful counseling/psychotherapy outcomes. Based on the empirical literature about working alliance, it seems that self-determination and self-efficacy theory (SDT/SET) can potentially be used as a motivational model to explain the relationship between working alliance and vocational rehabilitation (VR) outcomes. The purpose of this study is to evaluate three primary SDT/SET constructs, autonomous motivation, expectancy and engagement, as mediators for the relationship between working alliance and stages of change (SOC) for employment. Methods A serial multiple mediation analysis (SMMA) was computed to evaluate autonomy, outcome expectancy, and VR engagement as mediators of the relationship between working alliance and SOC for employment in a sample of 277 people with chronic illness and disability (CID) receiving services from state VR agencies in the United States. Results The SMMA results indicated that working alliance was positively associated with SOC for employment (total effect), while the direct effect between working alliance and SOC for employment was not significant after controlling for the effects of the mediators, indicating significant mediation effects. The mediation effects were estimates of the indirect effects for working alliance on SOC for employment through (a) autonomous motivation, (b) outcome expectancy, (c) VR engagement, and (d) autonomous motivation, outcome expectancy and VR engagement together. Conclusions The results indicated that a strong working alliance has the benefit of helping consumers develop autonomous motivation to work and increasing their vocational outcome expectancy and engagement in VR services, leading to employment.
Hadgraft, Nyssa T; Winkler, Elisabeth A H; Healy, Genevieve N; Lynch, Brigid M; Neuhaus, Maike; Eakin, Elizabeth G; Dunstan, David W; Owen, Neville; Fjeldsoe, Brianna S
2017-03-06
The Stand Up Victoria multi-component intervention successfully reduced workplace sitting time in both the short (three months) and long (12 months) term. To further understand how this intervention worked, we aimed to assess the impact of the intervention on four social-cognitive constructs, and examined whether these constructs mediated intervention effects on workplace sitting time at 3 and 12 months post-baseline. Two hundred and thirty one office-based workers (14 worksites, single government employer) were randomised to intervention or control conditions by worksite. The intervention comprised organisational, environmental, and individual level elements. Participant characteristics and social-cognitive constructs (perceived behavioural control, barrier self-efficacy, perceived organisational norms and knowledge) were measured through a self-administered online survey at baseline, 3 months and 12 months. Workplace sitting time (min/8 h day) was measured with the activPAL3 device. Single multi-level mediation models were performed for each construct at both time points. There were significant intervention effects at 3 months on perceived behavioural control, barrier self-efficacy and perceived organisational norms. Effects on perceived organisational norms were not significant at 12 months. Perceived behavioural control significantly mediated intervention effects at 3 months, accounting for a small portion of the total effect (indirect effect: -8.6 min/8 h day, 95% CI: -18.5, -3.6 min; 7.5% of total effect). At 12 months, barrier self-efficacy significantly mediated the intervention effects on workplace sitting time (indirect effect: -10.3 min/8 h day, 95% CI: -27.3, -2.2; 13.9% of total effect). No significant effects were observed for knowledge at either time point. Strategies that aim to increase workers' perceived control and self-efficacy over their sitting time may be helpful components of sedentary behaviour interventions in the workplace. However, social-cognitive factors only partially explain variation in workplace sitting reduction. Understanding the importance of other levels of influence (particularly interpersonal and environmental) for initiating and maintaining workplace sedentary behaviour change will be informative for intervention development and refinement. This study was prospectively registered with the Australian New Zealand Clinical Trials register ( ACTRN12611000742976 ) on 15 July 2011.
Fite, Jennifer E.; Bates, John E.; Holtzworth-Munroe, Amy; Dodge, Kenneth A.; Nay, Sandra Y.; Pettit, Gregory S.
2012-01-01
This study explored the K. A. Dodge (1986) model of social information processing as a mediator of the association between interparental relationship conflict and subsequent offspring romantic relationship conflict in young adulthood. The authors tested 4 social information processing stages (encoding, hostile attributions, generation of aggressive responses, and positive evaluation of aggressive responses) in separate models to explore their independent effects as potential mediators. There was no evidence of mediation for encoding and attributions. However, there was evidence of significant mediation for both the response generation and response evaluation stages of the model. Results suggest that the ability of offspring to generate varied social responses and effectively evaluate the potential outcome of their responses at least partially mediates the intergenerational transmission of relationship conflict. PMID:18540765
Afshar, Majid; Netzer, Giora; Mosier, Michael J; Cooper, Richard S; Adams, William; Burnham, Ellen L; Kovacs, Elizabeth J; Durazo-Arvizu, Ramon; Kliethermes, Stephanie
2017-11-01
This study aims to determine the relationship between tobacco use, inhalation injury, and ARDS in burn-injured adults. This study was an observational cohort of 2,485 primary burn admissions to a referral burn center between January 1, 2008 and March 15, 2015. Subjects were evaluated by methods used to account for mediation and traditional approaches (multivariable logistic regression and propensity score analysis). Mediation analysis examined both the (1) indirect effect of tobacco use via inhalation injury as the mediator on ARDS development and (2) the direct effect of tobacco use alone on ARDS development. ARDS development occurred in 6.8% ( n = 170) of the cohort. Inhalation injury occurred in 5.0% ( n = 125) of the cohort, and ARDS developed in 48.8% ( n = 83) of the subjects with inhalation injury. Tobacco use was 2-fold more common in subjects with ARDS. In the mediated model, the direct effect of tobacco use on ARDS, including interaction between tobacco use and inhalation injury, was not significant (odds ratio [OR] 1.63, 95% CI 0.91-2.92, P = .10). However, the indirect effect of tobacco use via inhalation injury as the mediator was significant (OR 1.61, 95% CI 1.25-2.07, P < .001), and the proportion of the total effect of tobacco use operating through the mediator was 55.6%. In the non-mediation models (multivariable logistic regression and propensity score analysis), which controlled for inhalation injury and other covariables, the OR for the association between tobacco use and ARDS was 1.84 (95% CI 1.22-2.81, P < .001) and 1.69 (95% CI 1.04-2.75, P = .03), respectively. In mediation analysis, inhalation injury was the overwhelming predictor for ARDS development, whereas tobacco use has its strongest effect indirectly through inhalation injury. Patients with at least moderate inhalation injury are at greatest risk for ARDS development despite baseline risk factors like tobacco use. Copyright © 2017 by Daedalus Enterprises.
Aazami, Sanaz; Shamsuddin, Khadijah; Akmal, Syaqirah
2015-01-01
We examined the mediating role of behavioral coping strategies in the association between work-family conflict and psychological distress. In particular, we examined the two directions of work-family conflict, namely, work interference into family and family interference into work. Furthermore, two coping styles in this study were adaptive and maladaptive coping strategies. This cross-sectional study was conducted among 429 Malaysian working women using self-reported data. The results of mediational analysis in the present study showed that adaptive coping strategy does not significantly mediate the effect of work-family conflict on psychological distress. However, maladaptive coping strategies significantly mediate the effect of work-family conflict on psychological distress. These results show that adaptive coping strategies, which aimed to improve the stressful situation, are not effective in managing stressor such as work-family conflict. We found that experiencing interrole conflict steers employees toward frequent use of maladaptive coping strategies which in turn lead to psychological distress. Interventions targeted at improvement of coping skills which are according to individual's needs and expectation may help working women to balance work and family demands. The important issue is to keep in mind that effective coping strategies are to control the situations not to eliminate work-family conflict.
Shamsuddin, Khadijah
2015-01-01
We examined the mediating role of behavioral coping strategies in the association between work-family conflict and psychological distress. In particular, we examined the two directions of work-family conflict, namely, work interference into family and family interference into work. Furthermore, two coping styles in this study were adaptive and maladaptive coping strategies. This cross-sectional study was conducted among 429 Malaysian working women using self-reported data. The results of mediational analysis in the present study showed that adaptive coping strategy does not significantly mediate the effect of work-family conflict on psychological distress. However, maladaptive coping strategies significantly mediate the effect of work-family conflict on psychological distress. These results show that adaptive coping strategies, which aimed to improve the stressful situation, are not effective in managing stressor such as work-family conflict. We found that experiencing interrole conflict steers employees toward frequent use of maladaptive coping strategies which in turn lead to psychological distress. Interventions targeted at improvement of coping skills which are according to individual's needs and expectation may help working women to balance work and family demands. The important issue is to keep in mind that effective coping strategies are to control the situations not to eliminate work-family conflict. PMID:25695097
Andrianto, Sonny; Jianhong, Ma; Hommey, Confidence; Damayanti, Devi; Wahyuni, Honey
2018-01-01
The present study examined the relationship between difficulty in re-entry adjustment and job embeddedness, considering the mediating role of sense of professional identity. The online data on demographic characteristics, difficulty on re-entry adjustment, sense of professional identity, and job embeddedness were collected from 178 Indonesian returnees from multiple organizations. The results showed that difficulty in re-entry adjustment was a significant predictor of a sense of professional identity; a sense of professional identity was a significant predictor of job embeddedness. Furthermore, sense of professional identity is an effective mediating variable, bridging the relationship between post-return conditions to the home country and work atmosphere. Finally, the key finding of this study was that sense of professional identity mediated the effect of difficulty in re-entry adjustment on job embeddedness. The theoretical and practical implications, study limitations, and future research needs of our findings are noted.
Katzmann, Josepha; Hautmann, Christopher; Greimel, Lisa; Imort, Stephanie; Pinior, Julia; Scholz, Kristin; Döpfner, Manfred
2017-05-01
Parent training (PT) delivered as a guided self-help intervention may be a cost- and time-effective intervention in the treatment of children with externalizing disorders. In face-to-face PT, parenting strategies have repeatedly been identified as mediating mechanisms for the decrease of children's problem behavior. Few studies have examined possible mediating effects in guided self-help interventions for parents. The present study aimed to investigate possible mediating variables of a behaviorally oriented guided self-help program for parents of children with externalizing problems compared to a nondirective intervention in a clinical sample. A sample of 110 parents of children with externalizing disorders (80 % boys) were randomized to either a behaviorally oriented or a nondirective guided self-help program. Four putative mediating variables were examined simultaneously in a multiple mediation model using structural equation modelling. The outcomes were child symptoms of ADHD and ODD as well as child externalizing problems, assessed at posttreatment. Analyses showed a significant indirect effect for dysfunctional parental attributions in favor of the group receiving the behavioral program, and significant effects of the behavioral program on positive and negative parenting and parental self-efficacy, compared to the nondirective intervention. Our results indicate that a decrease of dysfunctional parental attributions leads to a decrease of child externalizing problems when parents take part in a behaviorally oriented guided self-help program. However, none of the putative mediating variables could explain the decrease in child externalizing behavior problems in the nondirective group. A change in dysfunctional parental attributions should be considered as a possible mediator in the context of PT.
Ishioka, Kuka; Masaoka, Hiroyuki; Ito, Hidemi; Oze, Isao; Ito, Seiji; Tajika, Masahiro; Shimizu, Yasuhiro; Niwa, Yasumasa; Nakamura, Shigeo; Matsuo, Keitaro
2018-04-03
Aldehyde dehydrogenase 2 (ALDH2; rs671, Glu504Lys) and alcohol dehydrogenase 1B (ADH1B; rs1229984, His47Arg) polymorphisms have a strong impact on carcinogenic acetaldehyde accumulation after alcohol drinking. To date, however, evidence for a significant ALDH2-alcohol drinking interaction and a mediation effect of ALDH2/ADH1B through alcohol drinking on gastric cancer have remained unclear. We conducted two case-control studies to validate the interaction and to estimate the mediation effect on gastric cancer. We calculated odds ratios (OR) and 95% confidence intervals (CI) for ALDH2/ADH1B genotypes and alcohol drinking using conditional logistic regression models after adjustment for potential confounding in the HERPACC-2 (697 cases and 1372 controls) and HERPACC-3 studies (678 cases and 678 controls). We also conducted a mediation analysis of the combination of the two studies to assess whether the effects of these polymorphisms operated through alcohol drinking or through other pathways. ALDH2 Lys alleles had a higher risk with increased alcohol consumption compared with ALDH2 Glu/Glu (OR for heavy drinking, 3.57; 95% CI 2.04-6.27; P for trend = 0.007), indicating a significant ALDH2-alcohol drinking interaction (P interaction = 0.024). The mediation analysis indicated a significant positive direct effect (OR 1.67; 95% CI 1.38-2.03) and a protective indirect effect (OR 0.84; 95% CI 0.76-0.92) of the ALDH2 Lys alleles with the ALDH2-alcohol drinking interaction. No significant association of ADH1B with gastric cancer was observed. The observed ALDH2-alcohol drinking interaction and the direct effect of ALDH2 Lys alleles may suggest the involvement of acetaldehyde in the development of gastric cancer.
Social factors, weight perception, and weight control practices among adolescents in Mexico.
Bojorquez, Ietza; Villatoro, Jorge; Delgadillo, Marlene; Fleiz, Clara; Fregoso, Diana; Unikel, Claudia
2018-06-01
We evaluated the association of social factors and weight control practices in adolescents, and the mediation of this association by weight perception, in a national survey of students in Mexico ( n = 28,266). We employed multinomial and Poisson regression models and Sobel's test to assess mediation. Students whose mothers had a higher level of education were more likely to perceive themselves as overweight and also to engage in weight control practices. After adjusting for body weight perception, the effect of maternal education on weight control practices remained significant. Mediation tests were significant for boys and non-significant for girls.
McGee, Marjorie G
2015-04-01
Youth with disabilities experience greater levels of peer victimization and psychosocial distress than non-disabled youth. However, the extent to which exposure to peer victimization mediates the relationship between disability status and psychosocial distress is unknown. To determine whether the relationship between disability status and psychological distress was mediated by exposure to peer victimization, and if so, whether the mediation effects of peer victimization on psychosocial distress was moderated by sex. This cross-sectional study involved a series of regressions to test for mediation and moderated mediation using complex survey data from 6664 Oregon 11th graders. Peer victimization partially mediated the relationship between disability status and psychosocial distress. Sex, however, did not significantly moderate the mediating effects of peer victimization on psychosocial distress. Exposure to peer victimization mediated the relationship between disability status and psychosocial distress; there was little support for sex as a moderator. Copyright © 2015 Elsevier Inc. All rights reserved.
Zhou, Qing; Sandler, Irwin N; Millsap, Roger E; Wolchik, Sharlene A; Dawson-McClure, Spring R
2008-08-01
This study examines whether program effects on mother-child relationship quality and effective discipline mediated the 6-year longitudinal effects of the New Beginnings Program (NBP) to improve mental health and competence outcomes in 218 adolescents from divorced families in a randomized experimental trial. The NBP is a theory-based and parenting-focused preventive intervention to help children adjust to divorce, and it has previously shown significant main and/or Program x Baseline Risk interaction effects to reduce adolescents' mental health and social adaptation problems and to promote competence. Mediation analyses were conducted using single- and two-group (high and low baseline risk) structural equation modeling. A multiple-methods and multiple-informants approach was used to assess the putative mediators and adolescents' outcomes. Results indicated that program-induced improvement in maternal effective discipline at posttest mediated the intervention effect on adolescents' GPA at the 6-year follow-up. Moreover, program-induced improvement in mother-child relationship quality mediated the intervention effect on adolescents' mental health problems for those with high baseline risk for maladjustment. The discussion focuses on the implications of the mediation findings for advancing the developmental theories that informed the design of the NBP and the implications for implementation of the NBP in community settings. Copyright 2008 APA, all rights reserved.
Choi, Eun Ha; Kim, Eun-Kyung; Kim, Pil Bong
2018-03-31
EDUCATIONAL LEADERSHIP OF NURSING UNIT MANAGERS ON TEAM EFFECTIVENESS: Mediating Effects of Organizational Communication Satisfaction. This study identifies the effects of the educational leadership of nursing unit managers on team effectiveness and the mediating effects of organizational communication satisfaction; it highlights the importance of educational leadership and organizational communication and provides the data needed to enhance the education capacity of managers. The participants were 216 nursing unit managers of staff nurses at a tertiary hospital located in C Region, South Korea, and nurses who had worked for more than six months at the same hospital. This study was conducted using questionnaires on educational leadership, team effectiveness, and organizational communication satisfaction. Data analysis was performed with a t-test, ANOVA, Scheffé, Pearson's correlation coefficient, and simple and multiple regression analyses using SPSS version 23.0. Mediation analysis was tested using Baron and Kenny's regression analysis and a Sobel test. The mean score for the educational leadership of nursing unit managers was 3.74(±0.68); for organizational communication satisfaction, 3.14(±0.51); and for team effectiveness, 3.52(±0.49). Educational leadership was significantly positively correlated with team effectiveness and organizational communication satisfaction. Organizational communication satisfaction demonstrated a complete mediating effect on the relationship between educational leadership and team effectiveness (β=.61, p<.001) and was significant (Sobel test; Z=7.40, p<.001). The results indicate that the educational leadership of nursing unit managers increases communication satisfaction among nurses; this supports the idea that educational leadership can contribute to team effectiveness. This suggests that the educational leadership and communication capacity of nursing unit managers must be improved to enhance the performance of nursing organizations. Copyright © 2018. Published by Elsevier B.V.
Bramsen, Rikke Holm; Lasgaard, Mathias; Koss, Mary P; Elklit, Ask; Banner, Jytte
2014-01-01
The aim of the present study was to investigate the relationship between child maltreatment and severe early adolescent peer-on-peer sexual aggression, using a multiple mediator model. The study comprised 330 male Grade 9 students with a mean age of 14.9 years (SD=0.5). Estimates from the mediation model indicated significant indirect effects of child physical abuse on sexual aggression via peer influence and insecure-hostile masculinity. No significant total effect of child sexual abuse and child neglect on sexual aggression was found. Findings of the present study identify risk factors that are potentially changeable and therefore of value in informing the design of prevention programs aiming at early adolescent peer-on-peer sexual aggression in at-risk youth.
Guagliano, Justin M; Lonsdale, Chris; Rosenkranz, Richard R; Parker, Philip D; Agho, Kingsley E; Kolt, Gregory S
2015-11-01
The objective of this study was to test whether coaches' physical activity levels, contextual variables, and coaches' behavioural variables mediated the effect of an intervention on female basketball players' moderate-to-vigorous physical activity (MVPA) and inactivity in an organised youth sport (OYS) setting. Randomised controlled trial Data for the current study were derived from a two-armed, parallel-group randomised controlled trial. This study ran over the course of a 5-day OYS basketball program in 2 sports centres in Sydney, Australia. A convenience sample of 76 female players and 8 coaches were recruited. Coaches allocated to the intervention condition attended 2 coach education sessions, where strategies to increase MVPA and decrease inactivity were taught. There was a significant effect between changes in coach MVPA and player MVPA (unstandardised regression coefficient [B] = 0.26, 95% CI = 0.14 to 0.38) which coincided with a significant indirect effect (B = 1.80, 95% CI = 0.85 to 2.85). There was also a significant effect between changes in coach inactivity and player inactivity (B = -0.23, 95% CI = -0.14 to -0.31), which coincided with a significant indirect effect (B = -3.20, 95% CI = -0.14 to -0.31). No significant indirect effects were found for lesson context and coaches' behaviours variables. Coaches' MVPA and inactivity significantly mediated the effect of the intervention on player MVPA and inactivity, respectively. Consequently, coaches' physical activity levels appear to be important for influencing their players' physical activity levels. Published by Elsevier Ltd.
Association between age, distress, and orientations to happiness in individuals with disabilities.
Terrill, Alexandra L; Müller, Rachel; Jensen, Mark P; Molton, Ivan R; Ipsen, Catherine; Ravesloot, Craig
2015-02-01
To determine how age and distress are associated in individuals with disabilities, and how happiness and its components (meaning, pleasure, and engagement) mediate or moderate this relationship. These were cross-sectional analyses of survey data from 508 community-dwelling adults with a variety of self-reported health conditions and functional disabilities. Measures included the Orientations to Happiness Questionnaire and items from the Behavior Risk Factor Surveillance System. Greater distress was associated with lower global happiness in both mediation and moderation models. The mediation model showed that middle-aged participants (age: 45-64) scored lowest in global happiness, and the effect of age on distress was partially mediated by happiness. None of the happiness components mediated the relationship of age on distress. The moderation model showed a significant interaction effect for age and global happiness on distress, where younger participants low on happiness were significantly more distressed. Of the three happiness components, only meaning was significantly associated with distress. There was a significant interaction between age and meaning, where participants who were younger and scored low on the meaning scale reported significantly higher distress. Findings from this study lay groundwork for the development of clinical interventions to address distress in individuals with functional disabilities. Middle-aged and younger people with disabilities may be particularly affected by lower levels of happiness and might benefit from psychological interventions that focus on increasing overall well-being and providing meaning and purpose in life. PsycINFO Database Record (c) 2015 APA, all rights reserved.
Sheikh, Mashhood Ahmed
2017-01-01
The life course perspective, the risky families model, and stress-and-coping models provide the rationale for assessing the role of smoking as a mediator in the association between childhood adversity and anxious and depressive symptomatology (ADS) in adulthood. However, no previous study has assessed the independent mediating role of smoking in the association between childhood adversity and ADS in adulthood. Moreover, the importance of mediator-response confounding variables has rarely been demonstrated empirically in social and psychiatric epidemiology. The aim of this paper was to (i) assess the mediating role of smoking in adulthood in the association between childhood adversity and ADS in adulthood, and (ii) assess the change in estimates due to different mediator-response confounding factors (education, alcohol intake, and social support). The present analysis used data collected from 1994 to 2008 within the framework of the Tromsø Study ( N = 4,530), a representative prospective cohort study of men and women. Seven childhood adversities (low mother's education, low father's education, low financial conditions, exposure to passive smoke, psychological abuse, physical abuse, and substance abuse distress) were used to create a childhood adversity score. Smoking status was measured at a mean age of 54.7 years (Tromsø IV), and ADS in adulthood was measured at a mean age of 61.7 years (Tromsø V). Mediation analysis was used to assess the indirect effect and the proportion of mediated effect (%) of childhood adversity on ADS in adulthood via smoking in adulthood. The test-retest reliability of smoking was good (Kappa: 0.67, 95% CI: 0.63; 0.71) in this sample. Childhood adversity was associated with a 10% increased risk of smoking in adulthood (Relative risk: 1.10, 95% CI: 1.03; 1.18), and both childhood adversity and smoking in adulthood were associated with greater levels of ADS in adulthood ( p < 0.001). Smoking in adulthood did not significantly mediate the association between childhood adversity and ADS in adulthood. However, when education was excluded as a mediator-response confounding variable, the indirect effect of childhood adversity on ADS in adulthood was statistically significant ( p < 0.05). This study shows that a careful inclusion of potential confounding variables is important when assessing mediation.
Sheikh, Mashhood Ahmed
2017-01-01
The life course perspective, the risky families model, and stress-and-coping models provide the rationale for assessing the role of smoking as a mediator in the association between childhood adversity and anxious and depressive symptomatology (ADS) in adulthood. However, no previous study has assessed the independent mediating role of smoking in the association between childhood adversity and ADS in adulthood. Moreover, the importance of mediator-response confounding variables has rarely been demonstrated empirically in social and psychiatric epidemiology. The aim of this paper was to (i) assess the mediating role of smoking in adulthood in the association between childhood adversity and ADS in adulthood, and (ii) assess the change in estimates due to different mediator-response confounding factors (education, alcohol intake, and social support). The present analysis used data collected from 1994 to 2008 within the framework of the Tromsø Study (N = 4,530), a representative prospective cohort study of men and women. Seven childhood adversities (low mother's education, low father's education, low financial conditions, exposure to passive smoke, psychological abuse, physical abuse, and substance abuse distress) were used to create a childhood adversity score. Smoking status was measured at a mean age of 54.7 years (Tromsø IV), and ADS in adulthood was measured at a mean age of 61.7 years (Tromsø V). Mediation analysis was used to assess the indirect effect and the proportion of mediated effect (%) of childhood adversity on ADS in adulthood via smoking in adulthood. The test-retest reliability of smoking was good (Kappa: 0.67, 95% CI: 0.63; 0.71) in this sample. Childhood adversity was associated with a 10% increased risk of smoking in adulthood (Relative risk: 1.10, 95% CI: 1.03; 1.18), and both childhood adversity and smoking in adulthood were associated with greater levels of ADS in adulthood (p < 0.001). Smoking in adulthood did not significantly mediate the association between childhood adversity and ADS in adulthood. However, when education was excluded as a mediator-response confounding variable, the indirect effect of childhood adversity on ADS in adulthood was statistically significant (p < 0.05). This study shows that a careful inclusion of potential confounding variables is important when assessing mediation. PMID:28824498
ERIC Educational Resources Information Center
Stice, Eric; Presnell, Katherine; Gau, Jeff; Shaw, Heather
2007-01-01
The authors investigated mediators hypothesized to account for the effects of 2 eating disorder prevention programs using data from 355 adolescent girls who were randomized to a dissonance or a healthy weight intervention or an active control condition. The dissonance intervention produced significant reductions in outcomes (body…
Zhou, Yangen; Lu, Jiamei; Liu, Xianmin; Zhang, Pengcheng; Chen, Wuying
2014-01-01
Objective To explore the impact of Core self-evaluations on job burnout of nurses, and especially to test and verify the mediator role of organizational commitment between the two variables. Method Random cluster sampling was used to pick up participants sample, which consisted of 445 nurses of a hospital in Shanghai. Core self-evaluations questionnaire, job burnout scale and organizational commitment scale were administrated to the study participants. Results There are significant relationships between Core self-evaluations and dimensions of job burnout and organizational commitment. There is a significant mediation effect of organizational commitment between Core self-evaluations and job burnout. Conclusions To enhance nurses’ Core self-evaluations can reduce the incidence of job burnout. PMID:24755670
Ávila, Marisa; Brandão, Tânia; Teixeira, Joana; Coimbra, Joaquim Luis; Matos, Paula Mena
2015-11-01
This study examines the links between attachment, adaptation to breast cancer, and the mediating role played by emotional regulation processes. Participants were 127 women with breast cancer recruited in two public hospitals of Porto and at the Portuguese Cancer League. Women completed measures of attachment, quality of life, and emotion regulation. Path models were used to examine the associations between the constructs and to test the mediational hypotheses. Significant associations were found between attachment and adaptation. Dimensions of emotion regulation totally or partially mediated the associations between attachment and adaptation outcomes. Attachment security effects on interpersonal relations were totally mediated by communicating emotions. Also, attachment anxiety effect on physical well-being was totally mediated by rumination. Attachment avoidance effects on psychological outcomes were totally mediated by emotional control and partially mediated by communicating emotions for the case of interpersonal relations. This study highlights the importance of addressing emotional regulation jointly with attachment to deepen the comprehension of the relational processes implicated in adaptation to breast cancer. Results supported a mediational hypothesis, presenting emotional regulation processes as relevant dimensions for the understanding of attachment associations with adaptation to breast cancer. Copyright © 2015 John Wiley & Sons, Ltd.
Faulkner, Breanne; Goldstein, Abby L; Wekerle, Christine
2014-01-01
Longitudinal survey data were used to examine the relationship between two types of childhood maltreatment, abuse/neglect and exposure to intimate partner violence (IPV), and two outcomes, substance use and dating violence, within the past year. Participants were youth (N = 158, aged 16-19 at Time 3) involved with child protective services (CPS). A parallel multiple mediator model was used to test the hypothesis that trauma symptoms would mediate the relationship between both types of maltreatment and dating violence, marijuana, and alcohol use outcomes. Although both types of maltreatment were not directly associated with dating violence and substance use outcomes, the indirect effects of anxiety, anger, and dissociation on the relationship between maltreatment and substance use/dating violence were significant. Direct effects of both types of maltreatment on past year use of dating violence + alcohol use and dating violence + marijuana use were not significant, but results demonstrated a significant indirect effect for anger on the relationship between exposure to IPV and past year dating violence + marijuana use. No other indirect effects were significant. Findings highlight the negative effects of exposure to IPV and have implications for the development of prevention programming for youth transitioning out of CPS. © The Author(s) 2014.
Ben, J; Jamieson, L M; Priest, N; Parker, E J; Roberts-Thomson, K F; Lawrence, H P; Broughton, J; Paradies, Y
2014-09-01
Despite burgeoning evidence regarding the pathways by which experiences of racism influence health outcomes, little attention has been paid to the relationship between racism and oral health-related behaviours in particular. We hypothesised that self-reported racism was associated with tooth brushing, and that this association was mediated by perceived stress and sense of control and moderated by social support. Data from 365 pregnant Aboriginal Australian women were used to evaluate tooth brushing behaviour, sociodemographic factors, psychosocial factors, general health, risk behaviours and racism exposure. Bivariate associations were explored and hierarchical logistic regression models estimated odds ratios (OR) and 95% confidence intervals (CI) for tooth brushing. Perceived stress and sense of control were examined as mediators of the association between self-reported racism and tooth brushing using binary mediation with bootstrapping. High levels of self-reported racism persisted as a risk indicator for tooth brushing (OR 0.51, 95%CI 0.27,0.98) after controlling for significant covariates. Perceived stress mediated the relationship between self-reported racism and tooth brushing: the direct effect of racism on tooth brushing was attenuated, and the indirect effect on tooth brushing was significant (beta coefficient -0.09; bias-corrected 95%CI -0.166,-0.028; 48.1% of effect mediated). Sense of control was insignificant as a mediator of the relationship between racism and tooth brushing. High levels of self-reported racism were associated with non-optimal tooth brushing behaviours, and perceived stress mediated this association among this sample of pregnant Aboriginal women.. Limitations and implications are discussed.
Király, Orsolya; Urbán, Róbert; Griffiths, Mark D; Ágoston, Csilla; Nagygyörgy, Katalin; Kökönyei, Gyöngyi
2015-01-01
Background The rapid expansion of online video gaming as a leisure time activity has led to the appearance of problematic online gaming (POG). According to the literature, POG is associated with different psychiatric symptoms (eg, depression, anxiety) and with specific gaming motives (ie, escape, achievement). Based on studies of alcohol use that suggest a mediator role of drinking motives between distal influences (eg, trauma symptoms) and drinking problems, this study examined the assumption that there is an indirect link between psychiatric distress and POG via the mediation of gaming motives. Furthermore, it was also assumed that there was a moderator effect of gender and game type preference based on the important role gender plays in POG and the structural differences between different game types. Objective This study had two aims. The first aim was to test the mediating role of online gaming motives between psychiatric symptoms and problematic use of online games. The second aim was to test the moderator effect of gender and game type preference in this mediation model. Methods An online survey was conducted on a sample of online gamers (N=3186; age: mean 21.1, SD 5.9 years; male: 2859/3186, 89.74%). The Brief Symptom Inventory (BSI), the Motives for Online Gaming Questionnaire (MOGQ), and the Problematic Online Gaming Questionnaire (POGQ) were administered to assess general psychiatric distress, online gaming motives, and problematic online game use, respectively. Structural regression analyses within structural equation modeling were used to test the proposed mediation models and multigroup analyses were used to test gender and game type differences to determine possible moderating effects. Results The mediation models fitted the data adequately. The Global Severity Index (GSI) of the BSI indicated that the level of psychiatric distress had a significant positive direct effect (standardized effect=.35, P<.001) and a significant indirect (mediating) effect on POG (standardized effect=.194, P<.001) via 2 gaming motives: escape (standardized effect=.139, P<.001) and competition (standardized effect=.046, P<.001). The comparison of the 2 main gamer types showed no significant differences in the model. However, when comparing male and female players it was found that women had (1) slightly higher escape scores (on a 5-point Likert scale: mean 2.28, SD 1.14) than men (mean 1.87, SD 0.97) and (2) a stronger association between the escape motive and problematic online gaming (standardized effect size=.64, P<.001) than men (standardized effect size=.20, P=.001). Conclusions The results suggest that psychiatric distress is both directly and indirectly (via escape and competition motives) negatively associated with POG. Therefore, the exploration of psychiatric symptoms and gaming motives of POG can be helpful in the preparation of prevention and treatment programs. PMID:25855558
Király, Orsolya; Urbán, Róbert; Griffiths, Mark D; Ágoston, Csilla; Nagygyörgy, Katalin; Kökönyei, Gyöngyi; Demetrovics, Zsolt
2015-04-07
The rapid expansion of online video gaming as a leisure time activity has led to the appearance of problematic online gaming (POG). According to the literature, POG is associated with different psychiatric symptoms (eg, depression, anxiety) and with specific gaming motives (ie, escape, achievement). Based on studies of alcohol use that suggest a mediator role of drinking motives between distal influences (eg, trauma symptoms) and drinking problems, this study examined the assumption that there is an indirect link between psychiatric distress and POG via the mediation of gaming motives. Furthermore, it was also assumed that there was a moderator effect of gender and game type preference based on the important role gender plays in POG and the structural differences between different game types. This study had two aims. The first aim was to test the mediating role of online gaming motives between psychiatric symptoms and problematic use of online games. The second aim was to test the moderator effect of gender and game type preference in this mediation model. An online survey was conducted on a sample of online gamers (N=3186; age: mean 21.1, SD 5.9 years; male: 2859/3186, 89.74%). The Brief Symptom Inventory (BSI), the Motives for Online Gaming Questionnaire (MOGQ), and the Problematic Online Gaming Questionnaire (POGQ) were administered to assess general psychiatric distress, online gaming motives, and problematic online game use, respectively. Structural regression analyses within structural equation modeling were used to test the proposed mediation models and multigroup analyses were used to test gender and game type differences to determine possible moderating effects. The mediation models fitted the data adequately. The Global Severity Index (GSI) of the BSI indicated that the level of psychiatric distress had a significant positive direct effect (standardized effect=.35, P<.001) and a significant indirect (mediating) effect on POG (standardized effect=.194, P<.001) via 2 gaming motives: escape (standardized effect=.139, P<.001) and competition (standardized effect=.046, P<.001). The comparison of the 2 main gamer types showed no significant differences in the model. However, when comparing male and female players it was found that women had (1) slightly higher escape scores (on a 5-point Likert scale: mean 2.28, SD 1.14) than men (mean 1.87, SD 0.97) and (2) a stronger association between the escape motive and problematic online gaming (standardized effect size=.64, P<.001) than men (standardized effect size=.20, P=.001). The results suggest that psychiatric distress is both directly and indirectly (via escape and competition motives) negatively associated with POG. Therefore, the exploration of psychiatric symptoms and gaming motives of POG can be helpful in the preparation of prevention and treatment programs.
Osberg, Timothy M; Billingsley, Katherine; Eggert, Meredith; Insana, Maribeth
2012-08-01
Does exposure to college drinking movies impact upon subsequent college student drinking? If so, what mechanisms mediate such an effect? In the first study to address these questions, we assessed college drinking movie exposure in a sample of 479 college freshmen early in their first semester and examined its relation to subsequent drinking and drinking consequences one month later. Hypothesized mediators of this effect included college alcohol beliefs (beliefs that drinking is central to college life), positive and negative alcohol expectancies, and descriptive and injunctive norms. Using bootstrapping procedures, results indicated that movie exposure exerted direct effects on both drinking and drinking consequences. Movie exposure also had significant indirect effects on drinking through all of the hypothesized mediators, with the exception of negative alcohol expectancies. All mediated movie exposure's effects on drinking consequences, with the exception of injunctive norms. Contrast analyses revealed that college alcohol beliefs had the strongest mediational effects in the relationship between movie exposure and both drinking and consequences. The implications of these findings for precollege alcohol education programs are discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.
Linking Family Economic Hardship to Early Childhood Health: An Investigation of Mediating Pathways.
Hsu, Hui-Chin; Wickrama, Kandauda A S
2015-12-01
The underlying mechanisms through which family economic adversity influences child health are less understood. Taking a process-oriented approach, this study examined maternal mental health and investment in children, child health insurance, and child healthcare as mediators linking family economic hardship (FEH) to child health. A structural equation modeling was applied to test the hypothesized mediating model. After adjustment for sociodemographic risk factors, results revealed: (1) a significant direct path linking FEH to poor child health (effect size = .372), and (2) six significant mediating pathways (total effect size = .089). In two mediating pathways, exposures to FEH undermined mothers' mental health: in the first pathway poor maternal mental health led to decreased parental investment, which, in turn, contributed to poor child health, whereas in the second pathway the adverse effect of poor maternal mental health was cascaded through child unmet healthcare need, which resulted in poor child health. One pathway involved child insurance status, where the effect of FEH increased the likelihood to be uninsured, which led to unmet healthcare need, and, in turn, to poor health. Three pathways involved preventive care: in one pathway FEH contributed to poor preventive care, which led to unmet healthcare need and then to poor health; in the other two pathways where poor preventive care respectively gave rise to decreased investment in children or poor maternal mental health, which further contributed to poor child health. Results suggest that the association between FEH and children's health is mediated by multiple pathways.
SOCIAL COMPETENCE AND PSYCHOLOGICAL VULNERABILITY: THE MEDIATING ROLE OF FLOURISHING.
Uysal, Recep
2015-10-01
This study examined whether flourishing mediated the social competence and psychological vulnerability. Participants were 259 university students (147 women, 112 men; M age = 21.3 yr., SD = 1.7) who completed the Turkish versions of the Perceived Social Competence Scale, the Flourishing Scale, and the Psychological Vulnerability Scale. Mediation models were tested using the bootstrapping method to examine indirect effects. Consistent with the hypotheses, the results indicated a positive relationship between social competence and flourishing, and a negative relationship between social competence and psychological vulnerability. Results of the bootstrapping method revealed that flourishing significantly mediated the relationship between social competence and psychological vulnerability. The significance and limitations of the results were discussed.
Zhou, Shiyi; Da, Shu; Guo, Heng; Zhang, Xichao
2018-01-01
After the implementation of the universal two-child policy in 2016, more and more working women have found themselves caught in the dilemma of whether to raise a baby or be promoted, which exacerbates work–family conflicts among Chinese women. Few studies have examined the mediating effect of negative affect. The present study combined the conservation of resources model and affective events theory to examine the sequential mediating effect of negative affect and perceived stress in the relationship between work–family conflict and mental health. A valid sample of 351 full-time Chinese female employees was recruited in this study, and participants voluntarily answered online questionnaires. Pearson correlation analysis, structural equation modeling, and multiple mediation analysis were used to examine the relationships between work–family conflict, negative affect, perceived stress, and mental health in full-time female employees. We found that women’s perceptions of both work-to-family conflict and family-to-work conflict were significant negatively related to mental health. Additionally, the results showed that negative affect and perceived stress were negatively correlated with mental health. The 95% confidence intervals indicated the sequential mediating effect of negative affect and stress in the relationship between work–family conflict and mental health was significant, which supported the hypothesized sequential mediation model. The findings suggest that work–family conflicts affected the level of self-reported mental health, and this relationship functioned through the two sequential mediators of negative affect and perceived stress. PMID:29719522
Zhou, Shiyi; Da, Shu; Guo, Heng; Zhang, Xichao
2018-01-01
After the implementation of the universal two-child policy in 2016, more and more working women have found themselves caught in the dilemma of whether to raise a baby or be promoted, which exacerbates work-family conflicts among Chinese women. Few studies have examined the mediating effect of negative affect. The present study combined the conservation of resources model and affective events theory to examine the sequential mediating effect of negative affect and perceived stress in the relationship between work-family conflict and mental health. A valid sample of 351 full-time Chinese female employees was recruited in this study, and participants voluntarily answered online questionnaires. Pearson correlation analysis, structural equation modeling, and multiple mediation analysis were used to examine the relationships between work-family conflict, negative affect, perceived stress, and mental health in full-time female employees. We found that women's perceptions of both work-to-family conflict and family-to-work conflict were significant negatively related to mental health. Additionally, the results showed that negative affect and perceived stress were negatively correlated with mental health. The 95% confidence intervals indicated the sequential mediating effect of negative affect and stress in the relationship between work-family conflict and mental health was significant, which supported the hypothesized sequential mediation model. The findings suggest that work-family conflicts affected the level of self-reported mental health, and this relationship functioned through the two sequential mediators of negative affect and perceived stress.
Pernomian, Larissa; Pernomian, Laena; Gomes, Mayara S; da Silva, Carlos H T P
2015-12-15
The interplay between angiotensin AT1 receptors and MAS receptors relies on several inward regulatory mechanisms from renin-angiotensin system (RAS) including the functional crosstalk between angiotensin II and angiotensin-(1-7), the competitive AT1 antagonism exhibited by angiotensin-(1-7), the antagonist feature assigned to AT1/MAS heterodimerization on AT1 signaling and the AT1-mediated downregulation of angiotensin-converting enzyme 2 (ACE2). Recently, such interplay has acquired an important significance to RAS Pharmacology since a few studies have supporting strong evidences that MAS receptors mediate the effects elicited by AT1 antagonists. The present Perspective provides an overview of the regulatory mechanisms involving AT1 and MAS receptors, their significance to RAS Pharmacology and the future directions on the interplay between angiotensin receptors. Copyright © 2015 Elsevier B.V. All rights reserved.
The mediating role of pain acceptance during mindfulness-based cognitive therapy for headache.
Day, Melissa A; Thorn, Beverly E
2016-04-01
This study aimed to determine if mindfulness-based cognitive therapy (MBCT) engenders improvement in headache outcomes via the mechanisms specified by theory: (1) change in psychological process, (i.e., pain acceptance); and concurrently (2) change in cognitive content, (i.e., pain catastrophizing; headache management self-efficacy). A secondary analysis of a randomized controlled trial comparing MBCT to a medical treatment as usual, delayed treatment (DT) control was conducted. Participants were individuals with headache pain who completed MBCT or DT (N=24) at the Kilgo Headache Clinic or psychology clinic. Standardized measures of the primary outcome (pain interference) and proposed mediators were administered at pre- and post-treatment; change scores were calculated. Bootstrap mediation models were conducted. Pain acceptance emerged as a significant mediator of the group-interference relation (p<.05). Mediation models examining acceptance subscales showed nuances in this effect, with activity engagement emerging as a significant mediator (p<.05), but pain willingness not meeting criteria for mediation due to a non-significant pathway from the mediator to outcome. Criteria for mediation was also not met for the catastrophizing or self-efficacy models as neither of these variables significantly predicted pain interference. Pain acceptance, and specifically engagement in valued activities despite pain, may be a key mechanism underlying improvement in pain outcome during a MBCT for headache pain intervention. The theorized mediating role of cognitive content factors was not supported in this preliminary study. A large, definitive trial is warranted to replicate and extend the findings in order to streamline and optimize MBCT for headache. Copyright © 2016 Elsevier Ltd. All rights reserved.
Robertson, Michelle M; Huang, Yueng-Hsiang
2006-01-01
The effects of a workplace design and training intervention and the relationships between perceived satisfaction of office workplace design factors (layout and storage) and work performance measures (individual performance, group collaboration and effectiveness) were studied with 120 office workers using the Workplace Environment Questionnaire. Further, we examined whether environmental control had a direct effect on work performance, and then explored whether environmental control mediated or moderated the relationship between workplace design factors and work performance. Results showed a significant, positive impact of the intervention on environmental satisfaction for workstation layout. Satisfaction with workstation layout had a significant relationship with individual performance, group collaboration and effectiveness; and satisfaction with workstation storage had a significant relationship with individual performance and group collaboration. Environmental control had a direct impact on individual performance and group collaboration; whereas, the mediating and moderating effects of environmental control on the relationship between workplace design factors and outcome variables were not significant.
Coping as a mechanism linking stressful life events and mental health problems in adolescents.
Meng, Xiu Hong; Tao, Fang Biao; Wan, Yu Hui; Hu, Yan; Wang, Ren Xi
2011-12-01
Although stressful life events represent an etiologic factor of mental health problems in adolescents, few studies have been conducted to address mechanisms linking the stress-psychopathology relation. The present study was designed to examine coping as a mediate factor on the relationship between stressful life events and symptoms of anxiety and depression. The participants were 13 512 students from eight cities of China, who participated in a school-based survey. Data were collected by a questionnaire comprising coping, stressful life events, anxiety, and depressive symptoms. As a model, a series of regression equations were used to examine whether coping mediated the association between stressful life events and symptoms of anxiety and depression. Each dimension of stressful life events showed significant correlation with anxiety, depression and coping (all P<0.001). In the model to analyze mediate effects, all standardized coefficients (β) were significant (all P<0.01), indicating marked mediator effects. Furthermore, negative coping might account for more mediate effects than positive coping on this relationship. Coping partially mediated the relationship between stressful life events and mental health during adolescence. This study highlighted an important public health priority for preventive interventions targeting stress-related psychopathology, and for further promoting adolescents' mental health. Copyright © 2011 The Editorial Board of Biomedical and Environmental Sciences. Published by Elsevier B.V. All rights reserved.
Attentional control mediates the effect of social anxiety on positive affect☆
Morrison, Amanda S.; Heimberg, Richard G.
2015-01-01
The goal of the present studies was to examine whether attentional control, a self-regulatory attentional mechanism, mediates the effect of social anxiety on positive affect. We tested this mediation in two studies using undergraduate students selected to represent a broad range of severity of social anxiety. Self-report assessments of social anxiety, attentional control, and positive affect were collected in a cross-sectional design (Study 1) and in a longitudinal design with three assessment points (Study 2). Results of both studies supported the hypothesized mediational model. Specifically, social anxiety was inversely related to attentional control, which itself positively predicted positive affect. This mediation remained significant even when statistically controlling for the effects of depression. Additionally, the hypothesized model provided superior model fit to theoretically-grounded equivalent models in both studies. Implications of these findings for understanding diminished positive affect in social anxiety are discussed. PMID:23254261
Effect of theory of mind and peer victimization on the schizotypy-aggression relationship.
Lam, Bess Y H; Raine, Adrian; Lee, Tatia M C
2016-01-01
Prior longitudinal studies have established the relationship between schizophrenia and violence. However, previous studies on aggression and schizotypal personality are scarce. The present study examines whether peer victimization mediates the relationship between schizotypy and reactive-proactive aggression, and whether theory of mind (ToM) moderates this mediation. Schizotypy, peer victimization, reactive-proactive aggression, and ToM were assessed in 237 undergraduates. Peer victimization mediated the relationship between schizotypy and reactive aggression. ToM moderated this mediation effect; although peer victimization partially explains the schizotypy-aggression relationship, higher ToM skills weakened the detrimental effect of schizotypy on peer victimization which in turn reduces reactive aggression. In contrast, the moderated mediation was not significant for the proactive aggression model. Findings help delineate the underlying mechanism of the relationship between schizotypy and aggression. It is suggested that aggression could be reduced by enhancing ToM skills, thereby reducing peer victimization and the resultant schizotypy.
Effect of theory of mind and peer victimization on the schizotypy–aggression relationship
Lam, Bess Y H; Raine, Adrian; Lee, Tatia M C
2016-01-01
Prior longitudinal studies have established the relationship between schizophrenia and violence. However, previous studies on aggression and schizotypal personality are scarce. The present study examines whether peer victimization mediates the relationship between schizotypy and reactive-proactive aggression, and whether theory of mind (ToM) moderates this mediation. Schizotypy, peer victimization, reactive-proactive aggression, and ToM were assessed in 237 undergraduates. Peer victimization mediated the relationship between schizotypy and reactive aggression. ToM moderated this mediation effect; although peer victimization partially explains the schizotypy–aggression relationship, higher ToM skills weakened the detrimental effect of schizotypy on peer victimization which in turn reduces reactive aggression. In contrast, the moderated mediation was not significant for the proactive aggression model. Findings help delineate the underlying mechanism of the relationship between schizotypy and aggression. It is suggested that aggression could be reduced by enhancing ToM skills, thereby reducing peer victimization and the resultant schizotypy. PMID:27336052
Michael, Yvonne L; Carlson, Nichole E
2009-07-30
Using data from the SHAPE trial, a randomized 6-month neighborhood-based intervention designed to increase walking activity among older adults, this study identified and analyzed social-ecological factors mediating and moderating changes in walking activity. Three potential mediators (social cohesion, walking efficacy, and perception of neighborhood problems) and minutes of brisk walking were assessed at baseline, 3-months, and 6-months. One moderator, neighborhood walkability, was assessed using an administrative GIS database. The mediating effect of change in process variables on change in brisk walking was tested using a product-of-coefficients test, and we evaluated the moderating effect of neighborhood walkability on change in brisk walking by testing the significance of the interaction between walkability and intervention status. Only one of the hypothesized mediators, walking efficacy, explained the intervention effect (product of the coefficients (95% CI) = 8.72 (2.53, 15.56). Contrary to hypotheses, perceived neighborhood problems appeared to suppress the intervention effects (product of the coefficients (95% CI = -2.48, -5.6, -0.22). Neighborhood walkability did not moderate the intervention effect. Walking efficacy may be an important mediator of lay-lead walking interventions for sedentary older adults. Social-ecologic theory-based analyses can support clinical interventions to elucidate the mediators and moderators responsible for producing intervention effects.
Chen, Lei; Meng, Yue; Guo, Xiaoqing; Sheng, Xiaotong; Tai, Guihua; Zhang, Fenglei; Cheng, Hairong; Zhou, Yifa
2016-11-01
Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a potent cancer cell-specific apoptosis-inducing cytokine with little toxicity to most normal cells. Here, we report that gefitinib and TRAIL in combination produce a potent synergistic effect on TRAIL-sensitive human colon cancer HCT116 cells and an additive effect on TRAIL-resistant HT-29 cells. Interestingly, gefitinib increases the expression of cell surface receptors DR4 and DR5, possibly explaining the synergistic effect. Knockdown of DR4 and DR5 by siRNA significantly decreases gefitinib- and TRAIL-mediated cell apoptosis, supporting this idea. Because the inhibition of gefitinib-induced autophagy by 3-MA significantly decreases DR4 and DR5 upregulation, as well as reduces gefitinib- and TRAIL-induced apoptosis, we conclude that death receptor upregulation is autophagy mediated. Furthermore, our results indicate that death receptor expression may also be regulated by JNK activation, because pre-treatment of cells with JNK inhibitor SP600125 significantly decreases gefitinib-induced death receptor upregulation. Interestingly, SP600125 also inhibits the expression CHOP, yet CHOP has no impact on death receptor expressions. We also find here that phosphorylation of Akt and ERK might also be required for TRAIL sensitization. In summary, our results indicate that gefitinib effectively enhances TRAIL-induced apoptosis, likely via autophagy and JNK- mediated death receptor expression and phosphorylation of Akt and ERK.
Eather, Narelle; Morgan, Philip J; Lubans, David R
2013-05-28
Few studies have examined the mediators of behavior change in successful school-based physical activity interventions. The aim of this study was to explore potential mediators of physical activity in the Fit-4-Fun program for primary school children. Group randomized controlled trial. Four primary schools were recruited in April, 2011 and randomized by school into intervention or control conditions. Participants included 213 children (mean age = 10.7 years ± 0.6; 52.2% female) with the treatment group (n = 118) completing the 8-week multi-component Fit-4-Fun program. Participants were assessed at baseline, 3- and 6-months. Physical activity was measured using Yamax SW700 pedometers (mean steps/day) and questionnaires were used to assess constructs from Social Cognitive Theory and Competence Motivation Theory. Hypothesized mediators measured included social support from peers, parents and teachers; physical activity self-efficacy (barrier and task); enjoyment; and perceived school physical environment. Mediation was assessed using Preacher and Hayes' multiple mediation regression SPSS macro. Action theory (A), conceptual theory (B) and the significance of the product of coefficients (AB) are reported. The intervention had a significant effect on physical activity (p<0.001). The action theory test results revealed significant treatment effects at 3-months for perceived school environment (A=0.28, p<0.001); and at 6-month follow-up for perceived school environment (A=0.058, p<0.001), teacher social support (A=0.54, p<0.05) and enjoyment (A=-0.23, p<0.05). The conceptual theory test revealed a significant relationship between changes in teacher social support and changes in physical activity at 6-month follow-up (B=828, P<0.05). Teacher social support was shown to have a significant mediating effect on physical activity (AB = 445, CI = 77-1068 steps, proportion= 13%), and perceived school environment approached significance (AB = 434, CI= -415 to 1507 steps, proportion= 13%). The Fit-4-Fun program successfully targeted social support for physical activity provided by classroom teachers which contributed to improved physical activity in children. These results demonstrate that classroom teachers play a key role in influencing physical activity behavior outcomes in children.Trial Registration No: ACTRN12611000976987.
2013-01-01
Background Few studies have examined the mediators of behavior change in successful school-based physical activity interventions. The aim of this study was to explore potential mediators of physical activity in the Fit-4-Fun program for primary school children. Design Group randomized controlled trial. Methods Four primary schools were recruited in April, 2011 and randomized by school into intervention or control conditions. Participants included 213 children (mean age = 10.7 years ± 0.6; 52.2% female) with the treatment group (n = 118) completing the 8-week multi-component Fit-4-Fun program. Participants were assessed at baseline, 3- and 6-months. Physical activity was measured using Yamax SW700 pedometers (mean steps/day) and questionnaires were used to assess constructs from Social Cognitive Theory and Competence Motivation Theory. Hypothesized mediators measured included social support from peers, parents and teachers; physical activity self-efficacy (barrier and task); enjoyment; and perceived school physical environment. Mediation was assessed using Preacher and Hayes’ multiple mediation regression SPSS macro. Action theory (A), conceptual theory (B) and the significance of the product of coefficients (AB) are reported. Results The intervention had a significant effect on physical activity (p<0.001). The action theory test results revealed significant treatment effects at 3-months for perceived school environment (A=0.28, p<0.001); and at 6-month follow-up for perceived school environment (A=0.058, p<0.001), teacher social support (A=0.54, p<0.05) and enjoyment (A=-0.23, p<0.05). The conceptual theory test revealed a significant relationship between changes in teacher social support and changes in physical activity at 6-month follow-up (B=828, P<0.05). Teacher social support was shown to have a significant mediating effect on physical activity (AB = 445, CI = 77-1068 steps, proportion= 13%), and perceived school environment approached significance (AB = 434, CI= -415 to 1507 steps, proportion= 13%). Conclusions The Fit-4-Fun program successfully targeted social support for physical activity provided by classroom teachers which contributed to improved physical activity in children. These results demonstrate that classroom teachers play a key role in influencing physical activity behavior outcomes in children. Trial Registration No: ACTRN12611000976987 PMID:23714651
Food cravings mediate the relationship between chronic stress and body mass index.
Chao, Ariana; Grilo, Carlos M; White, Marney A; Sinha, Rajita
2015-06-01
This study examined the relationships between chronic stress, food cravings, and body mass index. A community-based sample of adults (N = 619) completed a comprehensive assessment battery and heights and weights were measured. Chronic stress had a significant direct effect on food cravings, and food cravings had a significant direct effect on body mass index. The total effect of chronic stress on body mass index was significant. Food cravings partially mediated the relationship between chronic stress and body mass index. These findings are consistent with research that chronic stress may potentiate motivation for rewarding substances and behaviors and indicate that high food cravings may contribute to stress-related weight gain. © The Author(s) 2015.
Buffart, Laurien M; Newton, Robert U; Chinapaw, Mai J; Taaffe, Dennis R; Spry, Nigel A; Denham, James W; Joseph, David J; Lamb, David S; Brug, Johannes; Galvão, Daniel A
2015-08-15
The current study examined effects, moderators (for whom), and mediators (working mechanisms) of 12 months of exercise on health-related quality of life (HRQoL) in older long-term survivors of prostate cancer. In total, 100 men aged 71.7 years (standard deviation, 6.4 years) were randomly assigned to 6 months of supervised aerobic and resistance exercise followed by 6 months of a home-based exercise maintenance program (EX group) or printed education material regarding physical activity for 12 months (PA group). Assessments took place at baseline and after 6 and 12 months. Generalized estimating equations were used to study the effects of EX versus PA on HRQoL at 6 and 12 months, adjusting for baseline HRQoL. The authors examined potential sociodemographic and clinical moderators by adding interaction terms, and potential physical and psychological mediators using the product-of-coefficients test. At 6 months, significant beneficial effects were found for global QoL, physical function, and social function in the EX group compared with the PA group. For physical function, beneficial effects were sustained at 12 months. Moderation analyses demonstrated larger effects of EX versus PA for patients who were married, started exercising sooner after their diagnosis, and previously used bisphosphonates. Changes in lower body functional performance significantly mediated the effect of EX on global QoL, physical function, and social function. No mediating effects on HRQoL were found for aerobic fitness, physical activity, fatigue, distress, or falls self-efficacy. Aerobic and resistance exercise appears to have beneficial effects on HRQoL among older, long-term survivors of prostate cancer. Effects were moderated by marital status, time since diagnosis, and use of bisphosphonates, and were mediated by lower body functional performance. © 2015 American Cancer Society.
Cutbush, Stacey; Williams, Jason; Miller, Shari
2016-11-01
This longitudinal study tested whether sexual harassment perpetration mediates the relationship between bullying perpetration and teen dating violence (TDV) perpetration and tested moderated mediation by assessing whether the developmental pathway varies by gender among middle school-aged youth. Although TDV has been associated with bullying and sexual harassment, the developmental relationship among all three behaviors has rarely been examined, especially by gender. The data were collected from one cohort of seventh grade middle school students (N = 612) from four schools. Students were surveyed every 6 months during seventh and eighth grades for a total of four waves of data collection. Structural equation modeling (SEM) was conducted to address the study aims, consisting of three stages: measurement models, mediation, and moderated mediation (otherwise known as Contrast of Mediated Effects). Results indicate no evidence of mediation. However, in the overall model, bullying and sexual harassment both emerged as significant predictors of TDV at a later time point. Among girls, only bullying significantly predicted TDV at a later time point, and, among boys, only sexual harassment significantly predicted TDV at a later time point. Prevention programs that target bullying and sexual harassment perpetration may reduce later perpetration of TDV. Further research is needed to disentangle the temporal relationships between these aggressive behaviors among youth.
2017-01-01
Purpose This study is aimed at identifying the relationships between medical school students’ academic burnout, empathy, and calling, and determining whether their calling has a mediating effect on the relationship between academic burnout and empathy. Methods A mixed method study was conducted. One hundred twenty-seven medical students completed a survey. Scales measuring academic burnout, medical students’ empathy, and calling were utilized. For statistical analysis, correlation analysis, descriptive statistics analysis, and hierarchical multiple regression analyses were conducted. For qualitative approach, eight medical students participated in a focus group interview. Results The study found that empathy has a statistically significant, negative correlation with academic burnout, while having a significant, positive correlation with calling. Sense of calling proved to be an effective mediator of the relationship between academic burnout and empathy. Conclusion This result demonstrates that calling is a key variable that mediates the relationship between medical students’ academic burnout and empathy. As such, this study provides baseline data for an education that could improve medical students’ empathy skills. PMID:28870019
Fossati, Andrea; Gratz, Kim L; Somma, Antonella; Maffei, Cesare; Borroni, Serena
2016-10-01
In order to evaluate if emotion dysregulation significantly mediates the relationships between childhood abuse and adult attachment and borderline personality disorder features, 354 community Italian adults were administered the Borderline Personality Inventory (Leichsenring, 1999a), the Difficulties in Emotion Regulation Scale (Gratz & Roemer, 2004), the Child Abuse and Trauma Scale (Sanders & Becker-Lausen, 1995), and the Attachment Style Questionnaire (Feeney, Noller, & Hanrahan, 1994). Hierarchical regression analyses showed that both childhood abuse and adult attachment were positively associated with emotion dysregulation and borderline personality features; however, only emotional abuse and the attachment dimension of need for approval were common predictors of both dependent variables. No significant interaction effects were detected in regression analyses. Mediation analyses provided support for partial mediation, revealing a significant mediating role of emotion dysregulation in the relationships between both emotional abuse and need for approval and borderline personality features in this community sample.
An Exploration of the Mediators Between Childhood Maltreatment and Intimate Partner Violence.
Smyth, Elizabeth J; Gardner, Frank L; Marks, Donald R; Moore, Zella E
2017-08-01
Intimate partner violence (IPV) is associated with numerous long-term consequences and warrants significant clinical attention. Recent theoretical models and empirical research have suggested that several factors play a role in the development of IPV perpetration, including childhood maltreatment, early maladaptive schemas, anger, and difficulties in emotion regulation. This study investigated the relationship between childhood maltreatment and IPV, specifically examining the mediation of this relationship by several variables thought to be related to this pernicious problem, including early maladaptive schemas, the experience of anger, and emotion regulation difficulties. In a young adult collegiate sample of 110 women in relationships, results of a bootstrapped multiple mediation analysis supported the hypothesis that childhood maltreatment predicted physical aggression within intimate partner relationships and found that the total indirect effect of childhood maltreatment on physical aggression through the 3 proposed mediators was significant. However, consistent with recent empirical findings, only difficulties in emotion regulation significantly mediated the relationship between childhood maltreatment and physical aggression within the sample.
Cheng, Fangman; Lin, Ping; Wang, Yini; Liu, Guojie; Li, Ling; Yu, Huai; Yu, Bo; Zhao, Zhenjuan; Gao, Xueqin
2018-05-01
The association between type D personality and coronary plaque vulnerability has been suggested. The objective of the study was to evaluate the potential mediating effects of health behavior on the association between type D personality and plaque vulnerability in coronary artery disease (CAD) patients. A total of 319 CAD patients were assessed for type D personality and health behavior via self-administered questionnaires. The plaque vulnerability, evaluated according to characteristics, accompaniment, and outcomes of plaque, was assessed by optical coherence tomography. Regression analysis showed that type D personality was independently associated with lipid plaque (odds ratio [OR] = 2.387, p = 0.001), thin cap fibroatheroma (TCFA) (OR = 2.366, p = 0.001), rupture (OR = 2.153, p = 0.002), and lipid arc (β = -0.291, p < 0.001). Mediation analyses showed that aspects of health behavior were significant mediators of the relationship between type D personality and plaque vulnerability. Psychological stress mediated the relationship between type D and lipid plaque (p = 0.030), TCFA (p = 0.034), and rupture (p = 0.013). Living habits significantly mediated the relationship between type D and lipid plaque (p = 0.028), TCFA (p = 0.036), but not rupture (p = 0.066). Participating in activities was not a significant mediator of the relationship between type D personality and lipid plaque (p = 0.115), TCFA (p = 0.115), or rupture (p = 0.077). Health behaviors (psychological stress and living habits) may be mediators of the association between type D personality and plaque vulnerability. Copyright © 2018 Elsevier Inc. All rights reserved.
Williamson, Timothy J; Stanton, Annette L; Austin, Jane E; Valdimarsdottir, Heiddis B; Wu, Lisa M; Krull, Jennifer L; Rini, Christine M
2017-10-01
A randomized experiment by Rini et al. (Health Psychol. 33(12):1541-1551, 2014) demonstrated that expressive helping, which involves three expressive writing sessions regarding hematopoietic stem cell transplant, followed by one writing session directed toward helping other stem cell transplant recipients, reduced psychological distress and bothersome physical symptoms among stem cell transplant recipients with elevated survivorship problems, relative to a neutral writing control condition. The current study evaluated whether word use reflective of emotional expression, cognitive processing, and change in perspective mediates the effects of expressive helping. The essays of 67 stem cell transplant recipients with high survivorship problems were analyzed with Linguistic Inquiry and Word Count. Multiple mediation modeling was used to test the hypothesized mechanisms of expressive helping on distress and bothersome physical symptoms. Relative to the control condition, expressive helping produced significant reductions in psychological distress and marginal reductions in physical symptom bother in the analyzed subset of participants from the parent study. Results indicated that positive emotion word use significantly mediated effects of expressive helping on reduced distress, but only for participants who used average (compared to above or below average) rates of negative emotion words. Cognitive processing and change in perspective did not significantly mediate benefits of expressive helping. Expressive helping carried its positive effects on distress through participants' higher expression of positive emotions when coupled with moderate rates of negative emotions. Findings highlight the benefit of expressing both positive and negative emotions in stressful situations.
Kennedy, Angie C; Adams, Adrienne E
2016-04-01
Using a cluster analysis approach with a sample of 205 young mothers recruited from community sites in an urban Midwestern setting, we examined the effects of cumulative violence exposure (community violence exposure, witnessing intimate partner violence, physical abuse by a caregiver, and sexual victimization, all with onset prior to age 13) on school participation, as mediated by attention and behavior problems in school. We identified five clusters of cumulative exposure, and found that the HiAll cluster (high levels of exposure to all four types) consistently fared the worst, with significantly higher attention and behavior problems, and lower school participation, in comparison with the LoAll cluster (low levels of exposure to all types). Behavior problems were a significant mediator of the effects of cumulative violence exposure on school participation, but attention problems were not. © The Author(s) 2014.
Loton, Daniel J.; Waters, Lea E.
2017-01-01
Preliminary studies of strength-based parenting (SBP), a style of parenting that seeks to build strengths knowledge and strengths use in one’s child, have reported benefits such as higher life satisfaction, subjective wellbeing, and positive emotions together with lower stress in children and teens. Two proximal mediators conveying these effects have been identified: teen’s own use of strengths and strength-based coping, along with a small moderating effect of growth mindsets relating to strengths. The current study tests the potential mediating effect of self-efficacy, a sense of agency in life, in the relationship between SBP and mental health (wellbeing and illbeing) in teens. Self efficacy has been linked to wellbeing and strengths processes in past studies and is classed as a basic human need and form of eudaimonic happiness. This study reconfirmed the adaptive benefits of SBP in a large sample of Australian adolescents (N = 11,368; 59% male; Mage = 14.04, SDage = 1.99) sourced from 28 schools. Using structural equation modeling, SBP significantly and directly predicted higher happiness and lower depression, with direct effects falling into the 85th and 95th percentile of meta-analytically derived individual differences effect sizes. In addition, self-efficacy was a significant partial mediator, accounting for 40.0% of the total effect on happiness and 52.7% of the total effect on distress. Self-efficacy was also a full mediator in the case of anxiety, with a strong indirect effect. Results suggest that building strengths in teens can also build self-efficacy, and given the large effect sizes, that SBP is a promising leverage point for increasing teen wellbeing. PMID:29066986
Loton, Daniel J; Waters, Lea E
2017-01-01
Preliminary studies of s trength-based parenting (SBP), a style of parenting that seeks to build strengths knowledge and strengths use in one's child, have reported benefits such as higher life satisfaction, subjective wellbeing, and positive emotions together with lower stress in children and teens. Two proximal mediators conveying these effects have been identified: teen's own use of strengths and strength-based coping, along with a small moderating effect of growth mindsets relating to strengths. The current study tests the potential mediating effect of self-efficacy, a sense of agency in life, in the relationship between SBP and mental health (wellbeing and illbeing) in teens. Self efficacy has been linked to wellbeing and strengths processes in past studies and is classed as a basic human need and form of eudaimonic happiness. This study reconfirmed the adaptive benefits of SBP in a large sample of Australian adolescents ( N = 11,368; 59% male; M age = 14.04, SD age = 1.99) sourced from 28 schools. Using structural equation modeling, SBP significantly and directly predicted higher happiness and lower depression, with direct effects falling into the 85th and 95th percentile of meta-analytically derived individual differences effect sizes. In addition, self-efficacy was a significant partial mediator, accounting for 40.0% of the total effect on happiness and 52.7% of the total effect on distress. Self-efficacy was also a full mediator in the case of anxiety, with a strong indirect effect. Results suggest that building strengths in teens can also build self-efficacy, and given the large effect sizes, that SBP is a promising leverage point for increasing teen wellbeing.
Morgan, Amy J; Mackinnon, Andrew J; Jorm, Anthony F
2013-02-01
To evaluate whether automated e-mails promoting effective self-help strategies for depressive symptoms were effective in changing self-help behavior, and whether this improved depression outcomes. 568 adults with sub-threshold depression participated in a randomized controlled trial and provided complete data. A series of 12 e-mails promoting the use of evidence-based self-help strategies was compared with e-mails providing non-directive depression information. Depression symptoms were assessed with the Patient Health Questionnaire depression scale (PHQ-9) and use of self-help strategies was assessed at baseline and post-intervention. We hypothesized that those receiving the self-help e-mails would increase their use of evidence-based self-help and this would be associated with improvements in depression. Mediation analyses were conducted using a non-parametric bootstrapping procedure. Total use of the self-help strategies promoted in the e-mails significantly mediated the effect of the intervention on depressive symptoms (B = -0.75, SE = 0.16, 95% CI: -1.06 to -0.48). The direct effect of the intervention on depressive symptoms was much smaller and not significant when the mediation path was included. The majority of the individual strategies also had a significant indirect effect on depressive symptoms. In adults with sub-threshold depression, automated e-mails based on behavior change principles can successfully increase use of self-help strategies, leading to a reduction in depressive symptoms. Copyright © 2012 Elsevier Ltd. All rights reserved.
Lavine; Snyder
1996-11-01
In two experiments, we examined the hypothesis that subjective perceptions of message quality mediate the functional matching effect in persuasion. In Experiment 1, participants whose attitudes and behaviors serve primarily a value-expressive function (i.e., low self-monitors) or a social-adjustive function (i.e., high self-monitors) were exposed to persuasive messages that contained value-expressive, social-adjustive, or both types of arguments in favor of voting. Functionally-relevant messages (i.e., the social-adjustive message for high self-monitors and the value-expressive message for low self-monitors) produced enhanced perceptions of message quality and persuasiveness, more positive attitudes, and more message-related behavior than functionally nonrelevant messages. Functionally mixed messages were generally more effective than messages containing only functionally nonrelevant arguments, but less effective than messages containing only functionally relevant arguments. Path analyses indicated that the influence of functional relevance on attitudes and behavior was significantly mediated by subjective perceptions of the quality of the message. In Experiment 2, we exposed participants to a functionally relevant or nonrelevant voting appeal five days before a presidential election. Results replicated those of Experiment 1; functionally relevant messages produced more favorable attitudes, and this effect was mediated by enhanced perceptions of message quality. Finally, postmessage attitudes exerted a significant influence on whether participants voted in the election, and this effect was mediated by voting intentions. Discussion focuses on the subjective nature of message evaluation and on the cognitive processes underlying the functional matching effect in persuasion.
Wodtke, Geoffrey T; Parbst, Matthew
2017-10-01
Although evidence indicates that neighborhoods affect educational outcomes, relatively little research has explored the mechanisms thought to mediate these effects. This study investigates whether school poverty mediates the effect of neighborhood context on academic achievement. Specifically, it uses longitudinal data from the Panel Study of Income Dynamics, counterfactual methods, and a value-added modeling strategy to estimate the total, natural direct, and natural indirect effects of exposure to an advantaged rather than disadvantaged neighborhood on reading and mathematics abilities during childhood and adolescence. Contrary to expectations, results indicate that school poverty is not a significant mediator of neighborhood effects during either developmental period. Although moving from a disadvantaged neighborhood to an advantaged neighborhood is estimated to substantially reduce subsequent exposure to school poverty and improve academic achievement, school poverty does not play an important mediating role because even the large differences in school composition linked to differences in neighborhood context appear to have no appreciable effect on achievement. An extensive battery of sensitivity analyses indicates that these results are highly robust to unobserved confounding, alternative model specifications, alternative measures of school context, and measurement error, which suggests that neighborhood effects on academic achievement are largely due to mediating factors unrelated to school poverty.
Cai, Wen-Peng; Pan, Yu; Zhang, Shui-Miao; Wei, Cun; Dong, Wei; Deng, Guang-Hui
2017-10-01
The current study aimed to explore the association of cognitive emotion regulation, social support, resilience and acute stress responses in Chinese soldiers and to understand the multiple mediation effects of social support and resilience on the relationship between cognitive emotion regulation and acute stress responses. A total of 1477 male soldiers completed mental scales, including the cognitive emotion regulation questionnaire-Chinese version, the perceived social support scale, the Chinese version of the Connor-Davidson resilience scale, and the military acute stress scale. As hypothesized, physiological responses, psychological responses, and acute stress were associated with negative-focused cognitive emotion regulation, and negatively associated with positive-focused cognitive emotion regulation, social supports and resilience. Besides, positive-focused cognitive emotion regulation, social support, and resilience were significantly associated with one another, and negative-focused cognitive emotion regulation was negatively associated with social support. Regression analysis and bootstrap analysis showed that social support and resilience had partly mediating effects on negative strategies and acute stress, and fully mediating effects on positive strategies and acute stress. These results thus indicate that military acute stress is significantly associated with cognitive emotion regulation, social support, and resilience, and that social support and resilience have multiple mediation effects on the relationship between cognitive emotion regulation and acute stress responses. Copyright © 2017 Elsevier B.V. All rights reserved.
van Stralen, M M; Yildirim, M; te Velde, S J; Brug, J; van Mechelen, W; Chinapaw, M J M
2011-10-01
Obesity prevention requires effective interventions targeting the so-called energy balance-related behaviours (that is, physical activity, sedentary and dietary behaviours). To improve (cost-)effectiveness of these interventions, one needs to know the working mechanisms underlying behavioural change. Mediation analyses evaluates whether an intervention works via hypothesised working mechanisms. Identifying mediators can prompt intervention developers to strengthen effective intervention components and remove/adapt ineffective components. This systematic review aims to identify psychosocial and environmental mediators of energy balance-related behaviours interventions for youth. Studies were identified by a systematic search of electronic databases (PubMed, Embase, PsycINFO, ERIC and SPORTDiscus). Studies were included if they (1) were school-based randomised controlled or quasi-experimental studies; (2) targeted energy balance behaviours; (3) conducted among children and adolescents (4-18 years of age); (4) written in English; and (5) conducted mediation analyses. A total of 24 studies were included. We found strong evidence for self-efficacy and moderate evidence for intention as mediators of physical activity interventions. Indications were found for attitude, knowledge and habit strength to be mediators of dietary behaviour interventions. The few sedentary behaviour interventions reporting on mediating effects prevented us from forming strong conclusions regarding mediators of sedentary behaviour interventions. The majority of interventions failed to significantly change hypothesised mediators because of ineffective intervention strategies, low power and/or use of insensitive measures. Despite its importance, few studies published results of mediation analysis, and more high-quality research into relevant mediators is necessary. On the basis of the limited number of published studies, self-efficacy and intention appear to be relevant mediators for physical activity interventions. Future intervention developers are advised to provide information on the theoretical base of their intervention including the strategies applied to provide insight into which strategies are effective in changing relevant mediators. In addition, future research is advised to focus on the development, validity, reliability and sensitivity of mediator measures.
van Stralen, M M; Yildirim, M; Velde, SJ te; Brug, J; van Mechelen, W; Chinapaw, M J M
2011-01-01
Objective: Obesity prevention requires effective interventions targeting the so-called energy balance-related behaviours (that is, physical activity, sedentary and dietary behaviours). To improve (cost-)effectiveness of these interventions, one needs to know the working mechanisms underlying behavioural change. Mediation analyses evaluates whether an intervention works via hypothesised working mechanisms. Identifying mediators can prompt intervention developers to strengthen effective intervention components and remove/adapt ineffective components. This systematic review aims to identify psychosocial and environmental mediators of energy balance-related behaviours interventions for youth. Method: Studies were identified by a systematic search of electronic databases (Pubmed, Embase, PsycINFO, ERIC and SPORTDiscus). Studies were included if they (1) were school-based randomised controlled or quasi-experimental studies; (2) targeted energy balance behaviours; (3) conducted among children and adolescents (4–18 years of age); (4) written in English; and (5) conducted mediation analyses. Results: A total of 24 studies were included. We found strong evidence for self-efficacy and moderate evidence for intention as mediators of physical activity interventions. Indications were found for attitude, knowledge and habit strength to be mediators of dietary behaviour interventions. The few sedentary behaviour interventions reporting on mediating effects prevented us from forming strong conclusions regarding mediators of sedentary behaviour interventions. The majority of interventions failed to significantly change hypothesised mediators because of ineffective intervention strategies, low power and/or use of insensitive measures. Conclusion: Despite its importance, few studies published results of mediation analysis, and more high-quality research into relevant mediators is necessary. On the basis of the limited number of published studies, self-efficacy and intention appear to be relevant mediators for physical activity interventions. Future intervention developers are advised to provide information on the theoretical base of their intervention including the strategies applied to provide insight into which strategies are effective in changing relevant mediators. In addition, future research is advised to focus on the development, validity, reliability and sensitivity of mediator measures. PMID:21487398
Wang, Qiongyu; Zhang, Aijun; Ma, Huiqun; Wang, Shijie; Ma, Yunyun; Zou, Xingwei; Li, Ruilian
2013-03-01
To investigate the effects of topical treatment with adenovirus-mediated promyelocytic leukemia gene (PML) gene in a psoriasis-like mouse model. The effect of adenovirus-mediated PML gene on the granular layer of mouse tail scale epidermis and epithelial mitosis were observed on longitudinal histological sections prepared from the tail skin and vaginal epithelium of the mice. Adenovirus-mediated PML gene significantly inhibited mitosis of mouse vaginal epithelial cells and promoted the formation of granular layer in mouse tail scale epidermis. The therapeutic effect of PML gene in the psoriasis-like mouse model may be associated with increased granular cells and suppressed epidemic cell proliferation.
Kong, Tianzhu; He, Yini; Auerbach, Randy P; McWhinnie, Chad M; Xiao, Jing
2015-04-01
In this study, we examined the mediator effects of overgeneral autobiographical memory (OGM) on the relationship between rumination and depression in 323 Chinese university students. 323 undergraduates completed the questionnaires measuring OGM (Autobiographical Memory Test), rumination (Ruminative Response Scale) and depression (Center for Epidemiologic Studies Depression Scale). Results using structural equation modeling showed that OGM partially-mediated the relationship between rumination and depression (χ 2 = 88.61, p < .01; RMSEA = .051; SRMR = .040; and CFI = .91). Bootstrap methods were used to assess the magnitude of the indirect effects. The results of the bootstrap estimation procedure and subsequent analyses indicated that the indirect effects of OGM on the relationship between rumination and depressive symptoms were significant. The results indicated that rumination and depression were partially mediated by OGM.
Karmakar, Monita; Elhai, Jon D; Amialchuk, Aliaksandr A; Tietjen, Gretchen E
2018-02-01
Personality traits (especially neuroticism) and childhood maltreatment have been independently related to many negative health outcomes later in life, including migraine. Studies have also shown the association between childhood maltreatment and maladaptive personality traits. The mediating role of personality traits on the relationship between childhood maltreatment and depression, psychological distress, and alcohol dependence has been extensively studied. However, this type of mediation has not been studied in the case of the development of migraine. This study investigated (1) the main effects of childhood abuse on personality traits, and of personality traits on migraine, and (2) the mediating role of neuroticism, on the relationship between childhood abuse and migraine in young adults. We analyzed retrospective, cross-sectional data from 13,493 adults aged 24-32 years in Wave 4 of the National Longitudinal Survey of Adolescent Health ("Add Health") data set. Participants were queried regarding maltreatment (emotional, physical, and sexual) during childhood, current Big Five personality traits (using mini International Personality Item Pool), current depression (using Center for Epidemiologic Studies-Depression Scale), perceived stress (Using Cohen's Perceived Stress Scale), and diagnosis of migraine by a health care provider. Linear and logistic regressions were used to assess the main effects of childhood maltreatment on the five personality traits (openness to experience, conscientiousness, extraversion, agreeableness, and neuroticism) and the main effect of the personality traits on self-reported provider diagnosis of migraine. A structural equation model (SEM) was used to examine the mediating role of neuroticism on the relationship between childhood maltreatment and migraine. Linear regression models showed that childhood abuse independently predicted increased neuroticism (β = 0.338, SE=±0.05, P < .001), and increased openness to experiences (β = 0.341, SE = ±0.06, P < .001) after adjusting for socio-demographic characteristics, current depression, and perceived stress. Logistic regression to examine the main effect of personality traits on migraine revealed that only neuroticism had a significant effect (OR = 1.07, 95%CI = 1.04-1.10) after controlling for childhood abuse, socio-demographic characteristics, current depression, and perceived stress. Our regression analyses showed that neuroticism, but not openness to experience, was a potential mediator for the relationship between childhood abuse and migraine. SEM confirmed significant mediation of the relationship between childhood abuse and migraine through neurotic personality traits (goodness of fit indices: CFI = 0.992, TLI = 0.979, RMSEA = 0.025), unadjusted for socio-demographic variables, depression, and stress. In addition to the indirect effect (β = 0.039, P < .01) of childhood abuse on migraine through neuroticism, there was also a significant direct effect (β = 0.143, P < .01) of childhood abuse on migraine. After adjusting for socio-demographic variables, other personality types, depression, and stress, both the direct effect (β = 0.127; P < .01) of childhood abuse on migraine and the indirect effect (β = 0.09; P < .01) of childhood abuse on migraine through neuroticism were attenuated, but remained significant. Childhood abuse is associated with personality and migraine. An estimated 21% of the total effect of childhood abuse on migraine could be explained by mediation through neuroticism in the unadjusted model. In the fully adjusted model, an estimated 8.7% of the total effect could be explained by mediation, although, self-reported data limit the ability to draw firm conclusions. © 2017 American Headache Society.
Effects of Active Listening, Reformulation, and Imitation on Mediator Success: Preliminary Results.
Fischer-Lokou, Jacques; Lamy, Lubomir; Guéguen, Nicolas; Dubarry, Alexandre
2016-06-01
An experiment with 212 students (100 men, 112 women; M age = 18.3 years, SD = 0.9) was carried out to compare the effect of four techniques used by mediators on the number of agreements contracted by negotiators. Under experimental conditions, mediators were asked either to rephrase (reformulate) negotiators' words or to imitate them or to show active listening behavior, or finally, to use a free technique. More agreements were reached in the active listening condition than in both free and rephrase conditions. Furthermore, mediators in the active listening condition were perceived, by the negotiators, as more efficient than mediators using other techniques, although there was no significant difference observed between the active listening and imitation conditions. © The Author(s) 2016.
Khanna, Vivek; Jain, Manish; Barthwal, Manoj Kumar; Kalita, Diganta; Boruah, Jeena Jyoti; Das, Siva Prasad; Islam, Nashreen S; Ramasarma, Tangirala; Dikshit, Madhu
2011-09-01
The present study was undertaken to assess the role of reactive oxygen species (ROS) in rat aortic ring vasoreactivity and integrity by using various peroxovanadate (pV) compounds. All the pV compounds (1nM-300 μM) used in the present study exerted concentration-dependent contractions on endothelium intact rat aortic rings. All compounds with an exception of DPV-asparagine (DPV-asn) significantly altered vascular integrity as shown by diminished KCl responses. Phenylephrine (PE)-mediated contractions (3nM-300 μM) were unaltered in the presence of these compounds. Acetylcholine (Ach)-mediated relaxation in PE (1μM) pre-contracted rings was significantly reduced in presence of diperoxovanadate (DPV), poly (sodium styrene sulfonate-co-maleate)-pV (PSS-CoM-pV) and poly (sodium styrene 4-sulfonate)-pV (PSS-pV). However, no significant change in Ach-mediated responses was observed in the presence of poly (acrylate)-pV (PAA-pV) and DPV-asn. DPV-asn was thus chosen to further elucidate mechanism involved in peroxide mediated modulation of vasoreactivity. DPV-asn (30nM - 300 μM) exerted significantly more stable contractions, that was found to be catalase (100U/ml) resistant in comparison with H(2)O(2) (30nM-300 μM) in endothelium intact aortic rings. These contractile responses were found to be dependent on extracellular Ca(2+) and were significantly inhibited in presence of ROS scavenger N-acetylcysteine (100 μM). Intracellular calcium chelation by BAPTA-AM (10μM) had no significant effect on DPV-asn (30nM-300 μM) mediated contraction. Pretreatment of aortic rings by rho-kinase inhibitor Y-27632 (10μM) significantly inhibited DPV-asn-mediated vasoconstriction indicating role of voltage-dependent Ca(2+) influx and downstream activation of rho-kinase. The small initial relaxant effect obtained on addition of DPV-asn (30nM-1 μM) in PE (1 μM) pre-contracted endothelium intact rings, was prevented in the presence of guanylate cyclase inhibitor, methylene blue (10 μM) and/or nitric oxide synthase (NOS) inhibitor, l-NAME (100 μM) suggesting involvement of nitric oxide and cGMP. DPV-asn, like H(2)O(2), exerted a response of vasoconstriction in normal arteries and vasodilation at low concentrations (30nM-1 μM) in PE-pre contracted rings with overlapping mechanisms. These findings suggest usefulness of DPV-asn having low toxicity, in exploring the peroxide-mediated effects on various vascular beds. The present study also convincingly demonstrates role of H(2)O(2) in the modulation of vasoreactivity by using stable peroxide DPV-asn and warrants future studies on peroxide mediated signaling from a newer perspective. 2011 Published by Elsevier Ltd.
Gholami, Tahereh; Pahlavian, Ahmad Heidari; Akbarzadeh, Mahdi; Motamedzade, Majid; Moghaddam, Rashid Heidari
2016-01-01
This study examined the hypothesis that burnout syndrome mediates effects of psychosocial risk factors and intensity of musculoskeletal disorders (MSDs) among hospital nurses. The sample was composed of 415 nurses from various wards across five hospitals of Iran's Hamedan University of Medical Sciences. Data were collected through three questionnaires: job content questionnaire, Maslach burnout inventory and visual analogue scale. Results of structural equation modeling with a mediating effect showed that psychosocial risk factors were significantly related to changes in burnout, which in turn affects intensity of MSDs.
Body dissatisfaction and psychological distress in adolescents: Is self-esteem a mediator?
Duchesne, Annie-Pier; Dion, Jacinthe; Lalande, Daniel; Bégin, Catherine; Émond, Claudie; Lalande, Gilles; McDuff, Pierre
2017-10-01
This brief report tests the mediating effect of self-esteem in the relationship between body dissatisfaction and symptoms of depression and anxiety. A sample of 409 adolescents (females = 58.4%) aged between 14 and 18 years completed the Rosenberg Self-Esteem Scale, the Contour Drawing Rating Scale, the Multidimensional Anxiety Scale for Children, and the Center for Epidemiologic Studies Depression Scale. Overall, results for the indirect effects analysis were significant for both anxiety and depression, which confirmed the mediating role of self-esteem. Thus, a negative perception of one's body image has the effect of lowering self-esteem, which in turn increases psychological distress.
Longitudinal Mediation of Processing Speed on Age-Related Change in Memory and Fluid Intelligence
Robitaille, Annie; Piccinin, Andrea M.; Muniz, Graciela; Hoffman, Lesa; Johansson, Boo; Deeg, Dorly J.H.; Aartsen, Marja J.; Comijs, Hannie C.; Hofer, Scott M.
2014-01-01
Age-related decline in processing speed has long been considered a key driver of cognitive aging. While the majority of empirical evidence for the processing speed hypothesis has been obtained from analyses of between-person age differences, longitudinal studies provide a direct test of within-person change. Using recent developments in longitudinal mediation analysis, we examine the speed–mediation hypothesis at both the within- and between-person levels in two longitudinal studies, LASA and OCTO-Twin. We found significant within-person indirect effects of change in age, such that increasing age was related to lower speed which, in turn, relates to lower performance across repeated measures on other cognitive outcomes. Although between-person indirect effects were also significant in LASA, they were not in OCTO-Twin. These differing magnitudes of direct and indirect effects across levels demonstrate the importance of separating between- and within-person effects in evaluating theoretical models of age-related change. PMID:23957224
Yokota, Aya; Takeuchi, Emiko; Iizuka, Misao; Ikegami, Yuko; Takayama, Hajime; Shinohara, Nobukata
2005-01-01
Using a panel of transfectant B lymphoma cells expressing varying amounts of the mutant Fas together with the endogenous wild type Fas, semi-quantitative studies on the dominant negative effect of a murine mutant Fas molecule lacking death domain were carried out. In anti-Fas antibody-mediated induction of apoptosis, the mutant molecules exerted significant dominant-negative effect only when their expression level was comparable to or higher than that of wild type molecules, or when exposed to low amounts of the antibody. The inhibitory effect was accompanied by the failure in DISC formation in spite of Fas aggregation. When they were subjected to T cell-mediated Fas-based induction of apoptosis, however, the dominant negative effect was prominent such that the expression of even a small amount of the mutant molecules resulted in significant inhibition. Such a strong inhibitory effect explains the dominant phenotype of this type of mutant Fas molecules in ALPS heterozygous patients and also implies that the physiological effectors for Fas in vivo are cells, i.e., FasL-expressing activated T cells.
Chan, Pei-Chi; Wang, Ya-Chin; Chen, Yi-Ling; Hsu, Wan-Ning; Tian, Yu-Feng; Hsieh, Po-Shiuan
2017-11-01
Elevations in C-reactive protein (CRP) levels are positively correlated with the progress of type 2 diabetes mellitus. However, the effect of CRP on pancreatic insulin secretion is unknown. Here, we showed that purified human CRP impaired insulin secretion in isolated mouse islets and NIT-1 insulin-secreting cells in dose- and time-dependent manners. CRP increased NADPH oxidase-mediated ROS (reactive oxygen species) production, which simultaneously promoted the production of nitrotyrosine (an indicator of RNS, reactive nitrogen species) and TNFα, to diminish cell viability, insulin secretion in islets and insulin-secreting cells. These CRP-mediated detrimental effects on cell viability and insulin secretion were significantly reversed by adding NAC (a potent antioxidant), apocynin (a selective NADPH oxidase inhibitor), L-NAME (a non-selective nitric oxide synthase (NOS) inhibitor), aminoguanidine (a selective iNOS inhibitor), PDTC (a selective NFκB inhibitor) or Enbrel (an anti-TNFα fusion protein). However, CRP-induced ROS production failed to change after adding L-NAME, aminoguanidine or PDTC. In isolated islets and NIT-1 cells, the elevated nitrotyrosine contents by CRP pretreatment were significantly suppressed by adding L-NAME but not PDTC. Conversely, CRP-induced increases in TNF-α production were significantly reversed by administration of PDTC but not L-NAME. In addition, wild-type mice treated with purified human CRP showed significant decreases in the insulin secretion index (HOMA-β cells) and the insulin stimulation index in isolated islets that were reversed by the addition of L-NAME, aminoguanidine or NAC. It is suggested that CRP-activated NADPH-oxidase redox signaling triggers iNOS-mediated RNS and NFκB-mediated proinflammatory cytokine production to cause β cell damage in state of inflammation. Copyright © 2017 Elsevier Inc. All rights reserved.
Emotion suppression and food intake in the context of a couple discussion: A dyadic analysis.
Côté, Marilou; Gagnon-Girouard, Marie-Pierre; Sabourin, Stéphane; Bégin, Catherine
2018-01-01
Using dyadic analysis, this study examined whether emotion suppression is a valid mediator in the relationship between mood change following a stressful couple discussion and subsequent food intake among cohabiting couples. In a laboratory setting, 80 heterosexual couples were presented with a bogus taste test immediately after discussing aspects that they would like each other to change. Mood change, emotion suppression and appetite perceptions were self-reported using visual analogue scales, and BMI was calculated based on objective measures. The moderated-mediation Actor-Partner Interdependence Model revealed a significant indirect conditional effect, showing that mood worsening was significantly associated with higher emotion suppression and that emotion suppression was significantly associated with more food intake among spouses with a high BMI. For spouses with a low BMI, the reverse effect was found, i.e., mood worsening was significantly associated with less food intake through the indirect effect of emotion suppression. Furthermore, an indirect partner effect was observed regardless of BMI, i.e., mood worsening was related to more food intake, which was mediated by the partner's emotion suppression. These results highlight the key role of emotion suppression in the relationship between mood change and food intake in the context of a stressful couple discussion. Copyright © 2017 Elsevier Ltd. All rights reserved.
O’Sullivan, Elizabeth J; Perrine, Cria G; Rasmussen, Kathleen M
2015-01-01
Background Compared with normal-weight women, women with obesity experience poorer breastfeeding outcomes. Successful breastfeeding among women with obesity is important for achieving national breastfeeding goals. Objectives The objectives were to determine whether the negative association between obesity and any or exclusive breastfeeding at 1 and 2 mo postpartum is mediated through breastfeeding problems that occur in the first 2 wk postpartum and if this association differs by parity. Methods Mothers (1151 normal-weight and 580 obese) in the Infant Feeding Practices Study II provided information on sociodemographic and psychosocial characteristics, body mass index, and breastfeeding outcomes. At 1 mo postpartum, participants reported the breastfeeding problems they experienced in the first 2 wk postpartum from a predefined list of 17 options. We used factor analysis to condense these problems into 4 explanatory variables; continuous factor scores were computed for use in further analyses. We used maximum likelihood logistic regression to assess mediation of the association between obesity and breastfeeding outcomes through early breastfeeding problems. Results No significant effect of obesity was found on any breastfeeding at 1 or 2 mo. At 1 mo postpartum, for both primiparous and multiparous women, there was a significant direct effect of obesity on exclusive breastfeeding and a significant indirect effect of obesity through early breastfeeding problems related to the explanatory mediating variable “Insufficient Milk” (throughout the remainder of the Abstract, this factor will be denoted by upper case notation). At 2 mo postpartum both the direct effect of obesity and the indirect effect through Insufficient Milk were significant in primiparous women but only the indirect effect remained significant in multiparous women. Conclusions Early problems related to Insufficient Milk may partially explain the association between obesity and poor exclusive breastfeeding outcomes. Women who are obese, particularly those reporting breastfeeding problems that grouped in the Insufficient Milk factor in the early postpartum period, may benefit from additional breastfeeding support. PMID:26290005
Wykes, Til; Reeder, Clare; Huddy, Vyv; Taylor, Rumina; Wood, Helen; Ghirasim, Natalia; Kontis, Dimitrios; Landau, Sabine
2012-01-01
Background Cognitive remediation (CRT) affects functioning but the extent and type of cognitive improvements necessary are unknown. Aim To develop and test models of how cognitive improvement transfers to work behaviour using the data from a current service. Method Participants (N49) with a support worker and a paid or voluntary job were offered CRT in a Phase 2 single group design with three assessments: baseline, post therapy and follow-up. Working memory, cognitive flexibility, planning and work outcomes were assessed. Results Three models were tested (mediation — cognitive improvements drive functioning improvement; moderation — post treatment cognitive level affects the impact of CRT on functioning; moderated mediation — cognition drives functioning improvements only after a certain level is achieved). There was evidence of mediation (planning improvement associated with improved work quality). There was no evidence that cognitive flexibility (total Wisconsin Card Sorting Test errors) and working memory (Wechsler Adult Intelligence Scale III digit span) mediated work functioning despite significant effects. There was some evidence of moderated mediation for planning improvement if participants had poorer memory and/or made fewer WCST errors. The total CRT effect on work quality was d = 0.55, but the indirect (planning-mediated CRT effect) was d = 0.082 Conclusion Planning improvements led to better work quality but only accounted for a small proportion of the total effect on work outcome. Other specific and non-specific effects of CRT and the work programme are likely to account for some of the remaining effect. This is the first time complex models have been tested and future Phase 3 studies need to further test mediation and moderated mediation models. PMID:22503640
Hsu, Mei-Chi; Tu, Chun-Hsien
2014-09-01
To test a hypothetical three-path mediation model evaluating the effects of functional status and depressive symptoms on the relationship between fatigue and quality of life in patients with cancer on the basis of the Theory of Unpleasant Symptoms. Patients with cancer often experience two or more concurrent, interrelated, mutually influential symptoms. Multiple unpleasant symptoms that have been proposed as mediating variables affecting quality of life in a model proposed in recent cancer studies are scanty. This study was a cross-sectional, descriptive, correlational design. Three hundred and twenty-six patients with cancer from oncology clinics were recruited in Taiwan between 2010-2011. Mediation models were tested and confirmed by applying structural modelling using Analysis of Moment Structures and the joint significance test. Fatigue affects patient quality of life directly or indirectly through functional status and depressive symptoms. These two mediating variables exhibited direct effects on quality of life. A path analysis approach revealed that 47·28 and 67·70% of the total effects of functional status and depressive symptoms, respectively, on the quality-of-life mediation models are attributable to 29·6 and 44·7% of the total effects between fatigue and quality of life, which mediated through two mediators, respectively. Quality of life may be enhanced by simultaneously improving physiological and psychological factors. An understanding of mediating effects is valuable in nursing care of patients with cancer, particularly in the early phase of treatment or in newly diagnosed stages I-III or recently treated patients with cancer in different disease stages. © 2013 John Wiley & Sons Ltd.
Food Craving as a Mediator between Addictive-like Eating and Problematic Eating Outcomes
Joyner, Michelle A.; Gearhardt, Ashley N.; White, Marney A.
2015-01-01
Background There is growing interest and debate about whether an addictive process contributes to problematic eating outcomes, such as obesity. Craving is a core component of addiction, but there has been little research on the relationship between addictive-like eating, craving, and eating-related concerns. In the current study, we examine the effect of both overall food craving and craving for different types of food on the relationship between addictive-like eating symptoms and elevated body mass index (BMI) and binge eating episodes. Methods In a community sample (n = 283), we conducted analyses to examine whether overall craving mediated the association between addictive-like eating and elevated BMI, as well as binge eating frequency. We also ran separate mediational models examining the indirect effect of cravings for sweets, fats, carbohydrates, and fast food fats on these same associations. Results Overall food craving was a significant partial mediator in the relationships between addictive-like eating and both elevated BMI and binge eating episodes. Cravings for sweets and other carbohydrates significantly mediated the relationship between addictive-like eating and binge eating episodes, while cravings for fats significantly mediated the relationship between addictive-like eating and elevated BMI. Conclusions Craving appears to be an important component in the pathway between addictive-like eating and problematic eating outcomes. The current results highlight the importance of further evaluating the role of an addictive process in problematic eating behaviors and potentially targeting food cravings in intervention approaches. PMID:26262570
Food craving as a mediator between addictive-like eating and problematic eating outcomes.
Joyner, Michelle A; Gearhardt, Ashley N; White, Marney A
2015-12-01
There is growing interest and debate about whether an addictive process contributes to problematic eating outcomes, such as obesity. Craving is a core component of addiction, but there has been little research on the relationship between addictive-like eating, craving, and eating-related concerns. In the current study, we examine the effect of both overall food craving and craving for different types of food on the relationship between addictive-like eating symptoms and elevated body mass index (BMI) and binge eating episodes. In a community sample (n=283), we conducted analyses to examine whether overall craving mediated the association between addictive-like eating and elevated BMI, as well as binge eating frequency. We also ran separate mediational models examining the indirect effect of cravings for sweets, fats, carbohydrates, and fast food fats on these same associations. Overall food craving was a significant partial mediator in the relationships between addictive-like eating and both elevated BMI and binge eating episodes. Cravings for sweets and other carbohydrates significantly mediated the relationship between addictive-like eating and binge eating episodes, while cravings for fats significantly mediated the relationship between addictive-like eating and elevated BMI. Craving appears to be an important component in the pathway between addictive-like eating and problematic eating outcomes. The current results highlight the importance of further evaluating the role of an addictive process in problematic eating behaviors and potentially targeting food cravings in intervention approaches. Copyright © 2015 Elsevier Ltd. All rights reserved.
Sun, Yong; Pu, Li-Yong; Lu, Ling; Wang, Xue-Hao; Zhang, Feng; Rao, Jian-Hua
2014-01-01
AIM: To investigate the effects of N-acetylcysteine (NAC) on endoplasmic reticulum (ER) stress and tissue injury during liver ischemia reperfusion injury (IRI). METHODS: Mice were injected with NAC (300 mg/kg) intraperitoneally 2 h before ischemia. Real-time polymerase chain reaction and western blotting determined ER stress molecules (GRP78, ATF4 and CHOP). To analyze the role of NAC in reactive oxygen species (ROS)-mediated ER stress and apoptosis, lactate dehydrogenase (LDH) was examined in cultured hepatocytes treated by H2O2 or thapsigargin (TG). RESULTS: NAC treatment significantly reduced the level of ROS and attenuated ROS-induced liver injury after IRI, based on glutathione, malondialdehyde, serum alanine aminotransferase levels, and histopathology. ROS-mediated ER stress was significantly inhibited in NAC-treated mice. In addition, NAC treatment significantly reduced caspase-3 activity and apoptosis after reperfusion, which correlated with the protein expression of Bcl-2 and Bcl-xl. Similarly, NAC treatment significantly inhibited LDH release from hepatocytes treated by H2O2 or TG. CONCLUSION: This study provides new evidence for the protective effects of NAC treatment on hepatocytes during IRI. Through inhibition of ROS-mediated ER stress, NAC may be critical to inhibit the ER-stress-related apoptosis pathway. PMID:25386077
O’Leary, Ann; Jemmott, John B.; Jemmott, Loretta Sweet; Bellamy, Scarlett; Ngwane, Zolani; Icard, Larry
2015-01-01
Background “Let Us Protect Our Future” is a sexual risk-reduction intervention for sixth-grade adolescents in South Africa. Tested in a cluster-randomized controlled trial, the intervention significantly reduced self-reported intercourse and unprotected intercourse during a 12-month follow-up period. Purpose The present analyses were conducted to identify moderators of the intervention’s efficacy as well as which theory-based variables mediated the intervention’s effects. Methods: Intervention efficacy over the 3-, 6-, and 12-month follow-ups was tested using generalized estimating equation (GEE) models. Results Living with their father in the home, parental strictness, and religiosity moderated the efficacy of the intervention in reducing unprotected intercourse. Self-efficacy to avoid risky situations and expected parental disapproval of their having intercourse, derived from Social Cognitive Theory, significantly mediated the intervention’s effect on abstinence. Conclusions This is the first study to demonstrate that Social Cognitive variables mediate the efficacy of a sexual risk-reduction intervention among South African adolescents. PMID:22618963
Chae, Sun-Mi; Kang, Hee Sun; Ra, Jin Suk
2017-02-01
This study examined whether body-esteem would mediate the association between physical activity and depression in adolescents. A total of 848 Korean high school students aged 15 to 18years completed a questionnaire on body-esteem, physical activity recall, and depression. Path analysis was used to test mediating effects of body-esteem on the association between physical activity and depression. Girls showed a significantly higher level of depressive symptoms than boys. Boys showed significantly higher levels of physical activity and body-esteem than girls. Body-esteem mediated the relation of physical activity with depression. Physical activity might reduce the risk of depression in addition to supporting body-esteem in adolescents. Interventions that reinforce healthy body-esteem and encourage physical activity would help prevent depression in adolescents. Future studies should examine the effects of programs addressing physical activity and body-esteem among adolescents with depressive symptoms. Copyright © 2016 Elsevier Inc. All rights reserved.
The role of leader influence tactics and safety climate in engaging employees' safety participation.
Clarke, Sharon; Ward, Katie
2006-10-01
This study examines the effect of leader influence tactics on employee safety participation in a U.K.-based manufacturing organization, examining the role of safety climate as a mediator. Structural equation modeling showed that leader influence tactics associated with a transformational leadership style had significant relationships with safety participation that were partially mediated by the safety climate (consultation) or fully mediated by the safety climate (inspirational appeals). In addition, leader influence tactics associated with a transactional leadership style had significant relationships with safety participation: rational persuasion (partially mediated by safety climate) and coalition tactics (direct effect). Thus, leaders may encourage safety participation using a combination of influence tactics, based on rational arguments, involvement in decision making, and generating enthusiasm for safety. The influence of building trust in managers is discussed as an underlying mechanism in this relationship. Practical implications are highlighted, including the design of leadership development programs, which may be particularly suited to high-reliability organizations.
Mitzel, Luke D; Vanable, Peter A; Brown, Jennifer L; Bostwick, Rebecca A; Sweeney, Shannon M; Carey, Michael P
2015-08-01
This study tested the hypothesis that depressive symptoms would mediate the association of HIV-related stigma to medication adherence. We recruited HIV-infected men who have sex with men (MSM; N = 66; 66 % White, 23 % African-American) from an outpatient infectious disease clinic, and asked them to complete self-report measures. Mediational analyses showed that depressive symptoms fully mediated the association between HIV-related stigma and adherence. That is, stigma-related experiences were positively associated with depressive symptoms and negatively associated with adherence, and, in the final model, depressive symptoms remained a significant correlate of adherence while stigma did not. A test of the indirect effect of stigma on adherence through depressive symptoms was also significant (unstandardized b = -0.19; bootstrap 95 % CI -0.45 to -0.01). These results highlight the importance of treating depressive symptoms in interventions aiming to improve medication adherence among HIV-infected MSM.
Patock-Peckham, Julie A; Morgan-Lopez, Antonio A
2007-09-01
Mediational links between parenting styles (authoritative, authoritarian, permissive), parental bond (positive, negative), depression, alcohol use and abuse were tested. A 2-group, multiple-indicator, multiple-cause structural equation model with 441 (216 female, 225 male) college students was examined. In general, a poor parental bond with one's father was highly predictive of depression, a well-known predictor of alcohol abuse and related problems for both genders. In contrast, a positive parental bond with one's father significantly mediated the positive effects of authoritative fathering on depression, which then decreased alcohol use problems for both genders. For women, a negative parental bond with one's father significantly mediated the effect of having an authoritarian father on depression, which increased alcohol use problems. These findings suggest that parental influences on pathways to alcohol abuse through depression (primarily through fathers for both genders) are distinct from pathways stemming from poor impulse control (with influences primarily from the same-sex parents for both genders).
Affective mediators of a physical activity intervention for depression in multiple sclerosis.
Kratz, Anna L; Ehde, Dawn M; Bombardier, Charles H
2014-02-01
Previous analyses showed that a telephone-based intervention to increase physical activity in individuals with multiple sclerosis (MS) and depression resulted in significantly improved depressive symptoms compared to a wait-list control group. The aim of this study was to test positive affect and negative affect as mediators of the effect of the physical activity counseling on depressive symptoms. Ninety-two adults with MS, who met diagnostic criteria for either major depression or dysthymia and who reported low levels of physical activity, were randomized 1:1 to a 12-week telephone-based motivational interviewing (MI) intervention to improve physical activity (n = 44) or to a 12-week wait-list control group (n = 48). Self-reported positive and negative affect, physical activity, and depressive symptoms were gathered at baseline and postintervention. Path-analysis was used to test whether positive affect and negative affect mediated the positive effects of the intervention on depressive symptoms. Both positive and negative affect were significant mediators of the effects of the intervention on depressive symptoms; however, only positive affect mediated the association between changes in physical activity and improved depressive symptoms. Findings support physical activity and positive affect as key mediators of the MI treatment effect on improved mood. Decreases in negative affect were also evident in the treatment group, but were not related to improved physical activity. Findings may suggest the use of exercise-based interventions in conjunction with treatments that specifically target negative affective mechanisms for depression. PsycINFO Database Record (c) 2014 APA, all rights reserved.
Fan, Sheng-Yu; Eiser, Christine; Ho, Ming-Chih; Lin, Cheng-Yao
2013-06-01
The aims of this study were to explore health-related quality of life (HRQOL) in patients with hepatocellular carcinoma (HCC). We report the following: (1) differences in HRQOL between patients with HCC and the general population; (2) significant physical and psychological predictors of HRQOL; and (3) mediation effects of illness perceptions and coping on HRQOL. Patients with HCC (n = 286) from Taiwan completed standardized measures of HRQOL, illness perception (cognitive representations, emotional representations and illness comprehensibility) and coping (emotion-oriented and problem-orientation coping). Demographic and physical variables were also collected. Patients with HCC had worse global HRQOL, physical, role, cognitive and social functioning, but better emotional functioning than the general population. Physical variables and cognitive representation were significant predictors of global HRQOL, physical functioning and emotional functioning. Cognitive representation mediated the relationships between physical variables and global HRQOL, physical functioning and emotional functioning, but coping only mediated the relationship between cognitive representation and global HRQOL. The results suggest that physical variables have direct effects on global HRQOL and physical functioning, but there were also partial mediations through cognitive representation. The effect of physical variables on emotional functioning was mediated through cognitive and emotional representations. Patients with better performance status and positive illness perceptions tended to report better HRQOL, but those with negative illness perceptions and who used more emotion-oriented coping had worse HRQOL. Limitations of the work associated with use of theory and measures developed in Europe and the US are discussed, as are the clinical implications for patients with HCC. Copyright © 2012 John Wiley & Sons, Ltd.
Gunathilake, Roshan; Oldmeadow, Christopher; McEvoy, Mark; Inder, Kerry J; Schofield, Peter W; Nair, Balakrishnan R; Attia, John
2016-12-01
The aim of the study was to determine how much of the association between obesity, measured by body mass index (BMI), and cognition in older persons is mediated through inflammation, fasting plasma glucose, and hypertriglyceridemia. Anthropometrics, high-sensitivity C-reactive protein (CRP), fasting plasma glucose, and serum triglycerides were measured in 3,256 community-dwelling individuals aged 55-85 years residing in Newcastle, New South Wales, Australia. Audio recorded cognitive screen (ARCS) was used to assess multiple cognitive domains. Mediation analyses showed very modest but significant direct mediation effects, whereby obesity was associated with better cognitive function after adjusting for potential confounders (controlled direct effect ≈ 1/500 point increase in the total ARCS score per 1.0-kg/m 2 increase in BMI). There were significant indirect negative mediation effects from BMI to cognition mediated through CRP, that is, increased BMI was associated with increased CRP which was associated with decreased cognition (natural indirect effect -0.20 unit; 95% confidence interval [CI] -0.39, -0.02), and through fasting plasma glucose, that is, increased BMI was associated with increased fasting plasma glucose which was associated with decreased cognition (natural indirect effect -0.12 unit; 95% CI -0.24, -0.01], but not through serum triglycerides. There is a weak positive association between obesity and cognitive performance in older persons, which is partially antagonized by inflammation and elevated fasting plasma glucose, but not hypertriglyceridemia. Further studies are needed to elucidate whether this is due to selection bias, or truly reflects biologically complex and counter balancing pathways involved in obesity. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Merino Ventosa, María; Urbanos-Garrido, Rosa M Maria Merino Ven Gmail Com
2016-09-01
This paper complements previous estimations regarding socioeconomic inequalities in obesity for Spanish adults, and provides new evidence about the mechanisms through which socioeconomic status (SES) affects obesity. Microdata from the Spanish National Health Survey (SNHS) 2011-2012 are analysed. Corrected concentration indices (CCI) are calculated to measure inequality. Path analysis is employed to disentangle direct and indirect effects of SES on obesity, where dietary patterns, physical activity and sleep habits act as mediator variables. Multivariate logistic models are used to select those exogenous variables to be included in the path diagram. Men and women are analysed separately. Our results show significant pro-rich inequality in the distribution of obesity (the poorer the more obese), particularly for women (CCI=-0.070 for men, CCI=-0.079 for women). The indirect effects of SES on obesity (those transmitted via mediator variables) are quite modest (3.3% for males, 2.4% for females) due to three reasons. Firstly, dietary habits do not show a significant mediating effect. Secondly, the mediating effect of physical activity in leisure time, although significant (14% for males, 11.1% for females), is offset by that related to main activity. Finally, sleep habits contribution to total effect of SES on obesity is statistically significant but small (roughly 1%). Our results indicate that promoting physical activity in leisure time for those with a low SES, particularly for men, would contribute to prevent obesity and to reduce health inequalities. Promotion of adequate sleep habits for women with a low SES might have a similar effect. However, interventions aimed to reduce sedentarism related to main activity, although useful to prevent obesity, would amplify the obesity socioeconomic gradient. Since effects of SES are different for men and women, socioeconomic health inequalities should be addressed also from a gender perspective. Copyright © 2016 Elsevier B.V. All rights reserved.
Kubo, Mitsuki; Egashira, Kensuke; Inoue, Takahiro; Koga, Jun-ichiro; Oda, Shinichiro; Chen, Ling; Nakano, Kaku; Matoba, Tetsuya; Kawashima, Yoshiaki; Hara, Kaori; Tsujimoto, Hiroyuki; Sueishi, Katsuo; Tominaga, Ryuji; Sunagawa, Kenji
2009-06-01
Recent clinical studies of therapeutic neovascularization using angiogenic growth factors demonstrated smaller therapeutic effects than those reported in animal experiments. We hypothesized that nanoparticle (NP)-mediated cell-selective delivery of statins to vascular endothelium would more effectively and integratively induce therapeutic neovascularization. In a murine hindlimb ischemia model, intramuscular injection of biodegradable polymeric NP resulted in cell-selective delivery of NP into the capillary and arteriolar endothelium of ischemic muscles for up to 2 weeks postinjection. NP-mediated statin delivery significantly enhanced recovery of blood perfusion to the ischemic limb, increased angiogenesis and arteriogenesis, and promoted expression of the protein kinase Akt, endothelial nitric oxide synthase (eNOS), and angiogenic growth factors. These effects were blocked in mice administered a nitric oxide synthase inhibitor, or in eNOS-deficient mice. NP-mediated cell-selective statin delivery may be a more effective and integrative strategy for therapeutic neovascularization in patients with severe organ ischemia.
Nakaya, K; Mizuno, R; Ohhashi, T
2001-12-01
We investigated whether supernatant cultured with melanoma cell lines B16-BL6 and K1735 or the Lewis lung carcinoma cell line (LLC) can regulate lymphatic pump activity with bioassay preparations isolated from murine iliac lymph vessels. B16-BL6 and LLC supernatants caused significant dilation of lymph microvessels with cessation of pump activity. B16-BL6 supernatant produced dose-related cessation of lymphatic pump activity. There was no significant tachyphylaxis in the supernatant-mediated inhibitory response of lymphatic pump activity. Pretreatment with 3 x 10(-5) M N(omega)-nitro-L-arginine methyl ester (L-NAME) or 10(-7) M or 10(-6) M glibenclamide and 5 x 10(-4) M 5-hydroxydecanoic acid caused significant reduction of supernatant-mediated inhibitory responses. Simultaneous treatment with 10(-3) M L-arginine and 3 x 10(-5) M L-NAME significantly lessened L-NAME-induced inhibition of the supernatant-mediated response, suggesting that endogenous nitric oxide (NO) plays important roles in supernatant-mediated inhibitory responses. Chemical treatment dialyzed substances of <1,000 molecular weight (MW), producing complete reduction of the supernatant-mediated response. In contrast, pretreatment with heating or digestion with protease had no significant effect on supernatant-mediated response. These findings suggest that B16-BL6 cells may release nonpeptide substance(s) of <1,000 MW, resulting in significant cessation of lymphatic pump activity via production and release of endogenous NO and activation of mitochondrial ATP-sensitive K(+) channels.
MacPherson, Heather A.; Weinstein, Sally M.; Henry, David B.; West, Amy E.
2016-01-01
Mediation analyses can identify mechanisms of change in Cognitive-Behavioral Therapy (CBT). However, few studies have analyzed mediators of CBT for youth internalizing disorders; only one trial evaluated treatment mechanisms for youth with mixed mood diagnoses. This study evaluated mediators in the randomized trial of Child- and Family-Focused CBT (CFF-CBT) versus Treatment As Usual (TAU) for pediatric bipolar disorder (PBD), adjunctive to pharmacotherapy. Sixty-nine children ages 7-13 with PBD were randomly assigned to CFF-CBT or TAU. Primary outcomes (child mood, functioning) and candidate mediators (family functioning, parent/child coping) were assessed at baseline and 4-, 8-, 12- (post-treatment), and 39-weeks (follow-up). Compared with TAU, children receiving CFF-CBT exhibited greater improvement in mania, depression, and global functioning. Several parent and family factors significantly improved in response to CFF-CBT versus TAU, and were associated with the CFF-CBT treatment effect. Specifically, parenting skills and coping, family flexibility, and family positive reframing showed promise as mediators of child mood symptoms and global functioning. Main or mediating effects for youth coping were not significant. CFF-CBT may impact children’s mood and functioning by improving parenting skills and coping, family flexibility, and family positive reframing. Findings highlight the importance of parent coping and family functioning in the treatment of PBD. PMID:27567973
Li, Zhen; Kesse-Guyot, Emmanuelle; Dumas, Orianne; Garcia-Aymerich, Judith; Leynaert, Bénédicte; Pison, Christophe; Le Moual, Nicole; Romieu, Isabelle; Siroux, Valérie; Camargo, Carlos A; Nadif, Rachel; Varraso, Raphaëlle
2017-02-01
It has been hypothesised that increased asthma prevalence in westernised countries is associated with changes in lifestyle factors, including a poorer diet. However, little is known regarding the association between diet quality and asthma. In the diet-asthma association, the role of BMI as a potential mediator needs clarification; moreover, potential effect modification by non-diet sources of oxidants, such as smoking, merits investigation. We investigated the association between diet quality and change in asthma symptoms, as well as assessed effect modification by smoking, while accounting for BMI as a potential mediator. Using data from the French prospective Epidemiological study on the Genetics and Environment of Asthma study, we assessed diet quality using the Alternate Healthy Eating Index 2010 (AHEI-2010) at baseline and change in asthma symptoms (stable (reference), worsening, improved; mean follow-up time: 7 years). Mediation analysis was used to disentangle total and direct effects and the indirect effect mediated by BMI. The analyses included 969 adults (mean age 43 years; 49 % men; 42 % ever asthma). We observed a significant interaction between smoking and AHEI-2010 on change in asthma symptoms (P for interaction=0·04). Among never smokers (n 499), we observed a positive total effect (multivariable OR 1·39; 95 % CI 1·07, 1·80) and a positive direct effect (OR 1·41; 95 % CI 1·09, 1·80) of the AHEI-2010 (per ten-point increment) on improved symptoms. No indirect effect mediated through BMI was observed (OR 0·99; 95 % CI 0·91, 1·07). Among former and current smokers, all effects were statistically non-significant. Better diet quality was associated with improved asthma symptoms over time in never smokers, independently of BMI.
Wang, Yan-yu; Jiang, Neng-zhi; Cheung, Eric F C; Sun, Hong-wei; Chan, Raymond C K
2015-09-01
Hopelessness, depression and impulsivity all contribute to the development of suicidal ideation in patients with major depressive disorder, but the pathway of these factors to suicidal ideation is not clear. This study examined the meditating effect of depression severity on the relationship between hopelessness and suicidal ideation and explored how this mediating effect was moderated by impulsivity. A total of 162 patients with major depressive disorder (MDD) completed a structured clinical diagnostic interview and a battery of scales assessing depression severity, hopelessness, suicidal ideation, and impulsivity. Regression analyses with bootstrapping methods were used to examine the mediating and moderating effects of various risk factors. Mediation analysis revealed a significant indirect effect of hopelessness on suicidal ideation, and the effect was fully mediated through depression severity. On moderation analysis, the moderating effects of the relationship between depression severity and suicidal ideation were significant in both the medium and high impulsivity groups. The present study was limited by the assessment of trait impulsivity and observer-rated depression severity, which might not fully reflect momentary impulsivity and feeling of depression when suicidal ideation occurs. Depression severity plays a mediator role in the relationship between hopelessness and suicidal ideation and this mechanism is contingent on the levels of impulsivity. MDD patients with higher impulsivity appear to be more likely to have suicidal ideations even when they are less depressed. These findings highlight the importance of impulsivity assessment and alleviation of depressive symptoms to prevent suicidality in patients with MDD. Copyright © 2015 Elsevier B.V. All rights reserved.
Mediation of an efficacious HIV risk reduction intervention for South African men.
O'Leary, Ann; Jemmott, John B; Jemmott, Loretta S; Bellamy, Scarlett; Icard, Larry D; Ngwane, Zolani
2015-10-01
"Men, Together Making a Difference!" is an HIV/STD risk-reduction intervention that significantly increased self-reported consistent condom use during vaginal intercourse compared with a health-promotion attention-control intervention among men (N = 1181) in Eastern Cape Province, South Africa. The present analyses were designed to identify mediators of the intervention's efficacy. The potential mediators were Social Cognitive Theory (SCT) constructs that the intervention targeted, including several aspects of condom-use self-efficacy, outcome expectancies, and knowledge. Mediation was assessed using a product-of-coefficients approach where an α path (the intervention's effect on the potential mediator) and a β path (the potential mediator's effect on the outcome of interest, adjusting for intervention) were estimated independently in a generalized estimating equations framework. Condom-use negotiation self-efficacy, technical-skill self-efficacy, and impulse-control self-efficacy were significant mediators. Although not mediators, descriptive norm and expected friends' approval of condom use predicted subsequent self-reported condom use, whereas the expected approval of sexual partner did not. The present results suggest that HIV/STD risk-reduction interventions that draw upon SCT and that address self-efficacy to negotiate condom use, to apply condoms correctly, and to exercise sufficient control when sexually aroused to use condoms may contribute to efforts to reduce sexual risk behavior among South African men. Future research must examine whether approaches that build normative support for condom use among men's friends are also efficacious.
POWER ANALYSIS FOR COMPLEX MEDIATIONAL DESIGNS USING MONTE CARLO METHODS
Thoemmes, Felix; MacKinnon, David P.; Reiser, Mark R.
2013-01-01
Applied researchers often include mediation effects in applications of advanced methods such as latent variable models and linear growth curve models. Guidance on how to estimate statistical power to detect mediation for these models has not yet been addressed in the literature. We describe a general framework for power analyses for complex mediational models. The approach is based on the well known technique of generating a large number of samples in a Monte Carlo study, and estimating power as the percentage of cases in which an estimate of interest is significantly different from zero. Examples of power calculation for commonly used mediational models are provided. Power analyses for the single mediator, multiple mediators, three-path mediation, mediation with latent variables, moderated mediation, and mediation in longitudinal designs are described. Annotated sample syntax for Mplus is appended and tabled values of required sample sizes are shown for some models. PMID:23935262
Annesi, James J; Mareno, Nicole
2015-12-01
To assess effects of cognitive-behavioural weight-loss treatments on self-efficacy to control emotionally cued eating and whether those changes mediate relationships between body satisfaction and emotional eating. Emotional eating is common, especially in women with obesity. A better understanding of relationships of its psychosocial correlates might benefit behavioural weight-loss treatments. A field-based, quantitative study incorporated two theoretically derived weight-loss treatments using repeated measures analyses that employed validated surveys. Women with obesity volunteered for a community-based weight-loss study and were assigned to either a treatment of a manual plus phone support (n = 47), or in-person contacts emphasizing self-regulation (n = 48), over 6 months. Both emphasized physical activity, healthy eating and building self-efficacy for enabling the health-behaviour changes. Data were collected between 2013-2014. Multiple regression analyses assessed predictors of self-efficacy change. Mixed-model analysis of variances assessed treatment differences in psychosocial changes. Mediation analyses assessed mediation of the relationships between body satisfaction and emotional eating changes. Changes in Overall mood and Self-regulation significantly predicted change in Self-efficacy to control emotionally cued eating. Changes in Body satisfaction, Emotional eating, Mood, Self-regulating eating and Self-efficacy were significant overall, and each significantly greater in the in-person treatment. Self-efficacy significantly mediated the relationship between changes in Body satisfaction and Emotional eating total (and Emotional eating when depressed or anxious, but not when frustrated/angry). Results clarified mediation of the dynamic relationship between body satisfaction and emotional eating, which might enable behavioural weight-loss treatments to better-address emotional eating. © 2015 John Wiley & Sons Ltd.
Jin, Yingli; Liu, Shuping; Ma, Qingshan; Xiao, Dong; Chen, Li
2017-01-05
High glucose concentration can induce injury of podocytes and berberine has a potent activity against diabetic nephropathy. However, whether and how berberine can inhibit high glucose-mediated injury of podocytes have not been clarified. This study tested the effect of berberine on high glucose-mediated apoptosis and the AMP-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR) activation and autophagy in podocytes. The results indicated that berberine significantly mitigated high glucose-decreased cell viability, and nephrin and podocin expression as well as apoptosis in mouse podocytes. Berberine significantly increased the AMPK activation and mitigated high glucose and/or the AMPK inhibitor, compound C-mediated mTOR activation and apoptosis in podocytes. Berberine significantly enhanced the AMPK activation and protected from high glucose-induced apoptosis in the AMPK-silencing podocytes. Furthermore, berberine significantly increased the high glucose-elevated Unc-51-like autophagy-activating kinase 1 (ULK1) S317/S555 phosphorylation, Beclin-1 expression, the ratios of LC3II to LC3I expression and the numbers of autophagosomes, but reduced ULK1 S757 phosphorylation in podocytes. In addition, berberine significantly attenuated compound C-mediated inhibition of autophagy in podocytes. The protective effect of berberine on high glucose-induced podocyte apoptosis was significantly mitigated by pre-treatment with 3-methyladenine or bafilomycin A1. Collectively, berberine enhanced autophagy and protected from high glucose-induced injury in podocytes by promoting the AMPK activation. Our findings may provide new insights into the molecular mechanisms underlying the anti-diabetic nephropathy effect of berberine and may aid in design of new therapies for intervention of diabetic nephropathy. Copyright © 2016 Elsevier B.V. All rights reserved.
Mahroum, Naim; Adawi, Mohammad; Sharif, Kassem; Waknin, Roy; Mahagna, Hussein; Bisharat, Bishara; Mahamid, Mahmud; Abu-Much, Arsalan; Amital, Howard; Luigi Bragazzi, Nicola; Watad, Abdulla
2018-01-01
The recent outbreak of Chikungunya virus in Italy represents a serious public health concern, which is attracting media coverage and generating public interest in terms of Internet searches and social media interactions. Here, we sought to assess the Chikungunya-related digital behavior and the interplay between epidemiological figures and novel data streams traffic. Reaction to the recent outbreak was analyzed in terms of Google Trends, Google News and Twitter traffic, Wikipedia visits and edits, and PubMed articles, exploiting structural modelling equations. A total of 233,678 page-views and 150 edits on the Italian Wikipedia page, 3,702 tweets, 149 scholarly articles, and 3,073 news articles were retrieved. The relationship between overall Chikungunya cases, as well as autochthonous cases, and tweets production was found to be fully mediated by Chikungunya-related web searches. However, in the allochthonous/imported cases model, tweet production was not found to be significantly mediated by epidemiological figures, with web searches still significantly mediating tweet production. Inconsistent relationships were detected in mediation models involving Wikipedia usage as a mediator variable. Similarly, the effect between news consumption and tweets production was suppressed by the Wikipedia usage. A further inconsistent mediation was found in the case of the effect between Wikipedia usage and tweets production, with web searches as a mediator variable. When adjusting for the Internet penetration index, similar findings could be obtained, with the important exception that in the adjusted model the relationship between GN and Twitter was found to be partially mediated by Wikipedia usage. Furthermore, the link between Wikipedia usage and PubMed/MEDLINE was fully mediated by GN, differently from what was found in the unadjusted model. In conclusion-a significant public reaction to the current Chikungunya outbreak was documented. Health authorities should be aware of this, recognizing the role of new technologies for collecting public concerns and replying to them, disseminating awareness and avoid misleading information.
Sharif, Kassem; Waknin, Roy; Mahagna, Hussein; Bisharat, Bishara; Mahamid, Mahmud; Abu-Much, Arsalan; Amital, Howard; Luigi Bragazzi, Nicola
2018-01-01
The recent outbreak of Chikungunya virus in Italy represents a serious public health concern, which is attracting media coverage and generating public interest in terms of Internet searches and social media interactions. Here, we sought to assess the Chikungunya-related digital behavior and the interplay between epidemiological figures and novel data streams traffic. Reaction to the recent outbreak was analyzed in terms of Google Trends, Google News and Twitter traffic, Wikipedia visits and edits, and PubMed articles, exploiting structural modelling equations. A total of 233,678 page-views and 150 edits on the Italian Wikipedia page, 3,702 tweets, 149 scholarly articles, and 3,073 news articles were retrieved. The relationship between overall Chikungunya cases, as well as autochthonous cases, and tweets production was found to be fully mediated by Chikungunya-related web searches. However, in the allochthonous/imported cases model, tweet production was not found to be significantly mediated by epidemiological figures, with web searches still significantly mediating tweet production. Inconsistent relationships were detected in mediation models involving Wikipedia usage as a mediator variable. Similarly, the effect between news consumption and tweets production was suppressed by the Wikipedia usage. A further inconsistent mediation was found in the case of the effect between Wikipedia usage and tweets production, with web searches as a mediator variable. When adjusting for the Internet penetration index, similar findings could be obtained, with the important exception that in the adjusted model the relationship between GN and Twitter was found to be partially mediated by Wikipedia usage. Furthermore, the link between Wikipedia usage and PubMed/MEDLINE was fully mediated by GN, differently from what was found in the unadjusted model. In conclusion—a significant public reaction to the current Chikungunya outbreak was documented. Health authorities should be aware of this, recognizing the role of new technologies for collecting public concerns and replying to them, disseminating awareness and avoid misleading information. PMID:29795578
Chhabra, Meenu; Mishra, Saroj; Sreekrishnan, T R
2008-12-01
Laccase from basidiomycete fungus Cyathus bulleri was evaluated for its ability to decolorize a number of reactive and acidic dyes in the presence of natural and synthetic mediators. The extent of decolorization was monitored at different mediator/dye concentrations and incubation time. Among the synthetic mediators, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) was effective at low mediator/dye ratios and resulted in 80-95% decolorization at rates that varied from 226 +/- 4 nmol min(-1) mg(-1) for Reactive Orange 1 to 1,333 +/- 15 nmol min(-1) mg(-1) for Reactive Red 198. Other synthetic mediators like 1-hydroxybenzotriazole and violuric acid showed both concentration- and time-dependent increases in percent decolorization. Natural mediators like vanillin, on the other hand, were found to be less effective on all the dyes except Reactive Orange 1. Computed rates of decolorization were about twofold lower than that with ABTS. The laccase-ABTS system also led to nearly 80% decolorization for the simulated dye mixture. No clear correlation between laccase activity on the mediator and its ability to decolorize dyes was found, but pH had a significant effect: Optimum pH for decolorization coincided with the optimum pH for mediator oxidation. The treated samples were also evaluated for toxicity in model microbial systems. The laccase-mediator system appears promising for treatment of textile wastewaters.
Walczak-Drzewiecka, Aurelia; Wyczólkowska, Janina; Dastych, Jaroslaw
2003-01-01
Upon contact with allergen, sensitized mast cells release highly active proinflammatory mediators. Allergen-mediated mast cell activation is an important mechanism in the pathogenesis of atopic asthma. Asthmatic patients are especially susceptible to air pollution. Epidemiologic studies found a positive correlation between severity of symptoms among asthmatic patients and the level of particulate matter (PM) in the air. Among the constituents of PM are metals and transition metals, which could mediate some of its adverse effects on human health. We sought to determine the effect of metal and transition metal ions on allergen-mediated mast cell activation. We observed that several metal and transition metal ions activated mast cells and enhanced allergen-mediated mast cell activation. Thus, Al(3+), Cd(2+), and Sr(2+) induced release of granule-associated N-acetyl-ss-d-hexosaminidase, and Al(3+) and Ni(2+) enhanced antigen-mediated release. Metal and transition metal ions also induced significant secretion of interleukin (IL)-4 and increased antigen-mediated IL-4 secretion in mast cells. These effects of metal and transition metal ions on mast cells were observed at concentrations that do not result in direct cytotoxicity and might be relevant for environmental exposure. Thus, metals and transition metals could increase the level of allergen-mediated mast cell activation, which might be one of the mechanisms mediating exacerbation of allergen-driven asthma symptoms by air pollution. PMID:12727598
Mendenhall, Amy N; Fristad, Mary A; Early, Theresa J
2009-06-01
This study investigated the impact of psychoeducation on service utilization and mood symptom severity in children with mood disorders. Parents' knowledge of mood disorders, beliefs about treatment, and perceptions of children's need for treatment were hypothesized to mediate the relationship between psychoeducation and service utilization and between psychoeducation and mood symptom severity. Linear mixed effects modeling and joint significance test for mediation were used in secondary data analyses of the multifamily psychoeducation group (MFPG) study, a randomized controlled trial of 165 children ages 8 to 12 years with mood disorders. A majority of those sampled were male (73%) and White, non-Hispanic (90%), and the median range of family income was $40,000-$59,000. Participation in MFPG significantly improved quality of services utilized, mediated by parents' beliefs about treatment. Participation in MFPG also significantly improved severity of child's mood symptoms, mediated by quality of services utilized. MFPG appears to be a psychoeducational intervention that helps parents to become better consumers of the mental health system who access higher quality services. Children's symptom severity decreases as a result. Copyright 2009 APA
Unravelling salutogenic mechanisms in the workplace: the role of learning.
Pijpker, Roald; Vaandrager, Lenneke; Bakker, Evert Jan; Koelen, Maria
To explore the moderating and mediating role(s) of learning within the relationship between sense of coherence (SOC) and generalized resistance resources. Cross-sectional study (N=481), using a self-administered questionnaire, of employees working in the healthcare sector in the Netherlands in 2017. Four residential healthcare settings and one healthcare-related Facebook group were involved. Multiple linear regression models were used to test for moderating and mediating effects of learning. Social relations, task significance, and job control significantly explained variance in SOC. Conceptual, social, and instrumental learning, combined, moderated the relationship between SOC and task significance. Instrumental learning moderated the relationship between job control and SOC. Social learning also mediated this relationship. Conceptual learning did not show any moderating or mediating effect. The relationship between SOC and the three GRRs seems to be strengthened or explained-to a certain extent-by instrumental and social learning. Healthcare organizations are recommended to promote learning through formal activities as well as through cooperation, feedback, sharing experiences, and job challenges. This requires employee participation and a multilevel interdisciplinary approach. Copyright © 2018 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.
Effort-reward imbalance and organisational injustice among aged nurses: a moderated mediation model.
Topa, Gabriela; Guglielmi, Dina; Depolo, Marco
2016-09-01
To test the effort-reward imbalance model among older nurses, expanding it to include the moderation of overcommitment and age in the stress-health complaints relationship, mediated by organisational injustice. The theoretical framework included the effort-reward imbalance, the uncertainty management and the socio-emotional selectivity models. Employing a two-wave design, the participants were 255 nurses aged 45 years and over, recruited from four large hospitals in Spain (Madrid and Basque Country). The direct effect of imbalance on health complaints was supported: it was significant when overcommitment was low but not when it was high. Organisational injustice mediated the influence of effort-reward imbalance on health complaints. The conditional effect of the mediation of organisational injustice was significant in three of the overcommitment/age conditions but it weakened, becoming non-significant, when the level of overcommitment was low and age was high. The study tested the model in nursing populations and expanded it to the settings of occupational health and safety at work. The results of this study highlight the importance of effort-reward imbalance and organisational justice for creating healthy work environments. © 2016 John Wiley & Sons Ltd.
Khalaila, Rabia
2015-03-01
The impact of cognitive factors on academic achievement is well documented. However, little is known about the mediating and moderating effects of non-cognitive, motivational and situational factors on academic achievement among nursing students. The aim of this study is to explore the direct and/or indirect effects of academic self-concept on academic achievement, and examine whether intrinsic motivation moderates the negative effect of test anxiety on academic achievement. This descriptive-correlational study was carried out on a convenience sample of 170 undergraduate nursing students, in an academic college in northern Israel. Academic motivation, academic self-concept and test anxiety scales were used as measuring instruments. Bootstrapping with resampling strategies was used for testing multiple mediators' model and examining the moderator effect. A higher self-concept was found to be directly related to greater academic achievement. Test anxiety and intrinsic motivation were found to be significant mediators in the relationship between self-concept and academic achievement. In addition, intrinsic motivation significantly moderated the negative effect of test anxiety on academic achievement. The results suggested that institutions should pay more attention to the enhancement of motivational factors (e.g., self-concept and motivation) and alleviate the negative impact of situational factors (e.g., test anxiety) when offering psycho-educational interventions designed to improve nursing students' academic achievements. Copyright © 2014 Elsevier Ltd. All rights reserved.
Dubow, Eric F; Boxer, Paul; Huesmann, L Rowell
2009-07-01
We examine the prediction of individuals' educational and occupational success at age 48 from contextual and personal variables assessed during their middle childhood and late adolescence. We focus particularly on the predictive role of the parents' educational level during middle childhood, controlling for other indices of socioeconomic status and children's IQ, and the mediating roles of negative family interactions, childhood behavior, and late adolescent aspirations. Data come from the Columbia County Longitudinal Study, which began in 1960 when all 856 third graders in a semi-rural county in New York State were interviewed along with their parents; participants were reinterviewed at ages 19, 30, and 48 (Eron et al, 1971; Huesmann et al., 2002). Parents' educational level when the child was 8 years old significantly predicted educational and occupational success for the child 40 years later. Structural models showed that parental educational level had no direct effects on child educational level or occupational prestige at age 48 but had significant indirect effects that were independent of the other predictor variables' effects. These indirect effects were mediated through age 19 educational aspirations and age 19 educational level. These results provide strong support for the unique predictive role of parental education on adult outcomes 40 years later and underscore the developmental importance of mediators of parent education effects such as late adolescent achievement and achievement-related aspirations.
2012-02-01
This study examined how parenting and family characteristics targeted in a selective prevention program mediated effects on key youth proximal outcomes related to violence perpetration. The selective intervention was evaluated within the context of a multi-site trial involving random assignment of 37 schools to four conditions: a universal intervention composed of a student social-cognitive curriculum and teacher training, a selective family-focused intervention with a subset of high-risk students, a condition combining these two interventions, and a no-intervention control condition. Two cohorts of sixth-grade students (total N = 1,062) exhibiting high levels of aggression and social influence were the sample for this study. Analyses of pre-post change compared to controls using intent-to-treat analyses found no significant effects. However, estimates incorporating participation of those assigned to the intervention and predicted participation among those not assigned revealed significant positive effects on student aggression, use of aggressive strategies for conflict management, and parental estimation of student's valuing of achievement. Findings also indicated intervention effects on two targeted family processes: discipline practices and family cohesion. Mediation analyses found evidence that change in these processes mediated effects on some outcomes, notably aggressive behavior and valuing of school achievement. Results support the notion that changing parenting practices and the quality of family relationships can prevent the escalation in aggression and maintain positive school engagement for high-risk youth.
Yu, Jessica; Fei, Kezhen; Fox, Ashley; Negron, Rennie; Horowitz, Carol
2016-01-01
The purpose of this study was to explore potential mediators of the relationship between depression and obesity in a sample of low-income, minority women. Data were extracted from a sample of 535 women enrolled in a weight loss intervention for the prevention of type 2 diabetes. Using a non-parametric bootstrapping procedure, the potential mediation effects of stress eating and sleep disturbance on the relationship between depression and obesity were tested. Results of a single mediation model indicated that depressive symptomatology was significantly associated with obesity (β=0.800, SE=0.290, p=0.006), and that stress eating (β=0.166, 95% CI [0.046, 0.328]) and sleep disturbance (β=1.032, 95% CI [0.612, 1.427]) were significant independent mediators of this relationship. Sleep disturbance remained a significant mediator in a combined mediation model (β=1.009, 95% CI [0.653, 1.399]). Findings add to the growing literature on the psychosocial factors implicated in the link between depression and obesity, particularly among disadvantaged populations. Future longitudinal research should aim to establish causal pathways between obesity, stress eating, sleep disturbance, and depression. Copyright © 2015 Asia Oceania Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.
Koenig, Julian; Li, Jian; Mauss, Daniel; Hoffmann, Kristina; Schmidt, Burkhard; Fischer, Joachim E.; Thayer, Julian F.
2016-01-01
Background Work stress is associated with an increased risk of pre-diabetes, Type 2 diabetes, and inflammation, as well as decreased autonomic nervous system function as measured, for example, via heart rate variability. We investigated the extent to which the association between work stress and glycemic status is mediated by vagally-mediated heart rate variability (vmHRV) and/or inflammation. Methods Cross-sectional data from the Mannheim Industrial Cohort Study (MICS) with 9,937 participants were analyzed. The root mean squared successive differences (RMSSD) from long-term heart rate monitoring during work and night time periods was used to index vmHRV. Fasting plasma glucose and glycosylated hemoglobin were assessed to determine glycemic status. High sensitive C-reactive protein levels were observed as a measure of systemic inflammation and the Effort-Reward-Imbalance scale was used to evaluate work stress. Mediation models were adjusted for age, sex, and occupational status, and estimations were bootstrapped (5,000 replications). Results Effort-Reward-Imbalance was significantly negatively associated with RMSSD and both glycosylated hemoglobin and fasting plasma glucose during both work and night time periods. Effort-Reward-Imbalance was observed to have a significant direct effect on glycosylated hemoglobin and significant indirect effects, through RMSSD, on both glycemic measures during both time periods. Introducing C-reactive protein as a further mediator to the model did not alter the indirect effects observed. C-reactive protein, as an exclusive mediator, was observed to have smaller direct and indirect effects on the glycemic measures as compared to when Effort-Reward-Imbalance was included in the model. Conclusions Our results suggest that the association between work stress and glycemic status is partially mediated through vmHRV independent of systemic inflammation as measured by C-reactive protein. We conclude that work stress may be an additional factor that promotes development of hyperglycemic-metabolic states. If supported by prospective evidence, these results may lead to new approaches for primary prevention of hyperglycemia in the workplace. PMID:27532642
Ferro, Mark A
2015-11-01
To examine the mediating effect of family functioning on the relation between maternal and adolescent depressive symptoms and determine whether the magnitude of the mediating effect is different for adolescents with and without chronic physical health conditions. Data come from the National Longitudinal Survey of Children and Youth. A representative survey of 11,813 adolescents and their mothers was included. Maternal and adolescent depressive symptoms were measured using the 12-item Center for Epidemiological Studies Depression Scale. Family functioning was measured using the McMaster Family Assessment Device. Multilevel multiple-group path analysis was used to examine potential mediating and moderating effects. Family functioning measured when adolescents were 14-15 years mediated the relation between maternal depressive symptoms (measured at 10-13 years) and adolescent depressive symptoms (measured at 16-19 years) for both adolescents with [αβ = 0.02 (0.02, 0.03)] and without chronic health conditions [αβ = 0.01 (0.00, 0.01)]. These findings provided evidence to suggest mediated moderation, Δαβ = 0.02 (0.01, 0.03), that is, the mediating effect of family functioning was significantly larger for adolescents with chronic health conditions. The mediating effect of family functioning in the relation between maternal and adolescent depressive symptoms is larger for adolescents with chronic health conditions. Within the framework of family-centered care, maternal depressive symptoms and family functioning are suitable targets for preventive intervention for adolescents with chronic health conditions.
Kong, Tianzhu; He, Yini; Auerbach, Randy P.; McWhinnie, Chad M.; Xiao, Jing
2015-01-01
Objective In this study, we examined the mediator effects of overgeneral autobiographical memory (OGM) on the relationship between rumination and depression in 323 Chinese university students. Method 323 undergraduates completed the questionnaires measuring OGM (Autobiographical Memory Test), rumination (Ruminative Response Scale) and depression (Center for Epidemiologic Studies Depression Scale). Results Results using structural equation modeling showed that OGM partially-mediated the relationship between rumination and depression (χ2 = 88.61, p < .01; RMSEA = .051; SRMR = .040; and CFI = .91). Bootstrap methods were used to assess the magnitude of the indirect effects. The results of the bootstrap estimation procedure and subsequent analyses indicated that the indirect effects of OGM on the relationship between rumination and depressive symptoms were significant. Conclusion The results indicated that rumination and depression were partially mediated by OGM. PMID:25977594
Audureau, Etienne; Pouchot, Jacques; Coste, Joël
2016-05-01
Negative effects of obesity on health-related quality of life (HRQoL) have been reported, especially in women, but the relative contribution of cardiometabolic and other obesity-related comorbidities to such effects remains unclear. Our objective was to model the association by sex between body mass index and HRQoL and to precisely quantify the indirect effects mediated by obesity-related comorbidities. Data were drawn from the latest French Decennial Health Survey, a nationwide cross-sectional study conducted in 2003 (21 239 adults aged 25-64 years analyzed). HRQoL was measured by the 36-item short-form health survey questionnaire. A mediation analysis based on the counterfactual framework was performed to quantify the proportion of obesity effects on HRQoL mediated by related comorbidities, including cardiometabolic risk factors (diabetes mellitus, hypertension, dyslipidemia) and diseases (ischemic heart disease, cerebrovascular, and peripheral vascular disease), musculoskeletal disorders, and asthma. After multiple linear regression, inverse associations were found between increasing body mass index category and physically oriented and most mentally oriented 36-item short-form health survey dimensions, with evidence of greater effects in women. Mediation analysis revealed that obesity effects were significantly mediated by several comorbidities, more apparently in men (eg, proportion of obesity class II total effect mediated via cardiometabolic factors: general health 27.0% [men] versus 13.6% [women]; proportion of obesity class II total effect mediated via total count of comorbidities: physical functioning 17.8% [men] versus 7.7% [women] and general health 37.1% [men] versus 20.3% [women]). Women have a greater overall impact of obesity on HRQoL, but with proportionally lower effects mediated by cardiometabolic and other obesity-related conditions, suggesting the possible role of other specific psychosocial processes. © 2016 American Heart Association, Inc.
Heritage, Brody; Quail, Michelle; Cocks, Naomi
2018-03-05
This study explored the predictors of the outcomes of turnover and occupation attrition intentions for speech-language pathologists. The researchers examined the mediating effects of job satisfaction and strain on the relationship between stress and the latter outcomes. Additionally, the researchers examined the importance of embeddedness in predicting turnover intentions after accounting for stress, strain and job satisfaction. An online questionnaire was used to explore turnover and attrition intentions in 293 Australian speech-language pathologists. Job satisfaction contributed to a significant indirect effect on the stress and turnover intention relationship, however strain did not. There was a significant direct effect between stress and turnover intention after accounting for covariates. Embeddedness and the perceived availability of alternative jobs were also found to be significant predictors of turnover intentions. The mediating model used to predict turnover intentions also predicted occupation attrition intentions. The effect of stress on occupation attrition intentions was indirect in nature, the direct effect negated by mediating variables. Qualitative data provided complementary evidence to the quantitative model. The findings indicate that the proposed parsimonious model adequately captures predictors of speech-language pathologists' turnover and occupation attrition intentions. Workplaces and the profession may wish to consider these retention factors.
Cao, Xiaoyi; Chen, Lin; Tian, Lang; Diao, Yongshu
2016-01-01
To examine the mediating effect of professional self-concept on the association between perceived organisational support and burnout among community health nurses in Chengdu, China. Burnout is a common phenomenon among nurses and previous studies have focused on work environmental factors contributing to burnout. Limited studies have examined the effects of perceived organisational support and professional self-concept on burnout among community health nurses. This was a cross-sectional study with 551 community health nurses in Chengdu, China, which included a two-stage sampling method. Structural equation modelling was used to examine the relationships among perceived organisational support, professional self-concept and burnout. The final sample included 456 nurses (82.7%). Perceived organisational support was a significant positive direct predictor for professional self-concept and a significant negative direct predictor for burnout. Professional self-concept was a significant negative direct contributor to burnout. Professional self-concept had a mediating effect on the relationship between perceived organisational support and burnout. Perceived organisational support may result in reduced burnout by facilitating the development of positive professional self-concept. Strategies such as establishing a supportive work environment and professional competence training may be effective methods for burnout prevention and management among community health nurses. © 2015 John Wiley & Sons Ltd.
Marsa-Sambola, Ferran; Williams, Joanne; Muldoon, Janine; Lawrence, Alistair; Connor, Melanie; Currie, Candace
2017-06-01
The relationship between adolescents' communication with their significant others (mother, father, and best friend) and quality of life (KIDSCREEN) was investigated in 2262 Scottish adolescent pet owners. The variable attachment to pets was also tested and assessed as a mediator of this relationship. A positive relationship between adolescents' communication with their significant other (mother, father, and best friend) and quality of life decreased when controlling for attachment to dogs. In cat owners, a positive relationship between communication with a best friend and quality of life decreased when controlling for attachment to cats. In cat and dog owners, attachment to these pets predicted higher levels of quality of life. Higher attachment to dogs and cats was explained by good best friend (IV) and attachment to pets (DV) and best friends. Mediation effects of attachment to dogs and cats might be explained in terms of the caring activities associated with these types of pets.
Laing, Sharon S; Jones, Salene M W
2016-11-01
This study investigates the mediation effect of anxiety and depression on the relationship between perceived health-promoting workplace culture and presenteeism. Paper surveys were distributed to 4703 state employees. Variables included symptoms of depression (Patient Health Questionnaire-2 [PHQ-2]); anxiety (General Health Questionnaire-12 [GHQ-12]); perceived workplace support for healthy living and physical activity; and presenteeism (Work Productivity and Activity Impairment Questionnaire). Correlational analyses assessed relationships among culture, mental health, and productivity. Indirect effects of workplace culture on productivity, mediated by anxiety and depression symptoms were significant (P's = 0.002). Healthy living culture and anxiety were significantly associated (r = -0.110, P < 0.01), and anxiety and presenteeism were significantly associated (r = +0.239, P < 0.01). Anxiety and depression determine the impact of perceived health promotive workplace culture on employee productivity. The paper highlights importance of health promotive practices targeting employee mental well-being.
Zhang, Wei; Wu, Yan Yan
2017-03-01
Analyzing the 2011-2013 China Health and Retirement Longitudinal Study with 14,507 respondents from 393 neighborhoods, and applying generalized linear mixed-effects model, this study examines how individual-level education and neighborhood-socioeconomic contexts affect health through social engagement. Findings reveal that measures of social engagement-social activity and productive activity-are significantly related to self-rated health and partially mediate the effects of individual-level education. Neighborhood-socioeconomic contexts have independent effects on self-rated health beyond individual socio-demographics, and social activity mediates the effects of neighborhood recreational facilities. This study is among the first to simultaneously explore the health effects of individual and neighborhood-level socioeconomic conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.
du Prel, Jean-Baptist; Iskenius, Mario; Peter, Richard
2014-12-01
To investigate multiple mediations of the association between education and depressive symptoms (BDI-V) by work-related stress (ERI) and social isolation, the regional variation of the first mediation and a potential moderating effect of regional unemployment rate. 6339 employees born in 1959 and 1965 were randomly recruited from 222 sample points in a German cohort study on work, age, health and work participation. A multilevel model of moderated lower-level mediation was used to investigate the confirmatory research question. Multiple mediations were tested corresponding to Baron and Kenny. These analyses were stratified for age and adjusted for sex, negative affectivity and overcommitment. In the association between education and depressive symptoms, indirect effects of work-related stress and social isolation were significant in both age cohorts whereas a direct association was observable in the younger cohort, only. The significant regional variation in the association between work-related stress and depressive symptoms was not statistically explained by regional unemployment rate. Our findings point out that work-related stress and social isolation play an intermediary role between education and depressive symptoms in middle-aged employees.
Marotta, Phillip L; Voisin, Dexter R
2017-10-01
The following study assessed whether future orientation mediated the effects of peer norms and parental monitoring on delinquency and substance use among 549 African American adolescents. Structural equation modeling computed direct and indirect (meditational) relationships between parental monitoring and peer norms through future orientation. Parental monitoring significantly correlated with lower delinquency through future orientation ( B = -.05, standard deviation = .01, p < .01). Future orientation mediated more than quarter (27.70%) of the total effect of parental monitoring on delinquency. Overall findings underscore the importance of strengthening resilience factors for African American youth, especially those who live in low-income communities.
Survival of the fittest: implications of self-reliance and coping for leaders and team performance.
Daus, C S; Joplin, J R
1999-01-01
Using a laboratory methodology, the authors sought to establish an association between self-reliance (based on attachment theory) and team performance and satisfaction. Three hypotheses (direct effect, mediator, and moderator) were tested. With a sample of 187 students, the authors compared leader self-reliance characteristics with group member self-reliance characteristics (group n = 50) as predictors of group performance and satisfaction. Only group member counterdependence was predictive of decreased performance. Further, the authors examined the possible mediating and moderating effects of coping on the self-reliance-group effectiveness relationships. Coping did not mediate the relationship but did operate as a significant moderator in some instances.
Mereish, Ethan H; N'cho, Hammad S; Green, Carlton E; Jernigan, Maryam M; Helms, Janet E
2016-01-01
Discrimination is related to depression and poor self-esteem among Black men. Poorer self-esteem is also associated with depression. However, there is limited research identifying how self-esteem may mediate the associations between discrimination and depressive symptoms for disparate ethnic groups of Black men. The purpose of this study was to examine ethnic groups as a moderator of the mediating effects of self-esteem on the relationship between discrimination and depressive symptoms among a nationally representative sample of African American (n = 1201) and Afro-Caribbean American men (n = 545) in the National Survey of American Life. Due to cultural socialization differences, we hypothesized that self-esteem would mediate the associations between discrimination and depressive symptoms only for African American men, but not Afro-Caribbean American men. Moderated-mediation regression analyses indicated that the conditional indirect effects of discrimination on depressive symptoms through self-esteem were significant for African American men, but not for Afro-Caribbean men. Our results highlight important ethnic differences among Black men.
Drerup, Michelle L; Johnson, Thomas J; Bindl, Stephen
2011-12-01
Johnson et al. (2008b) reported that, in a college student sample, the effect of religiousness on alcohol use was mediated by negative beliefs about alcohol, social influences, and spiritual well-being, and that these variables in turn impacted alcohol use and problems both directly and indirectly via motives for drinking. This study attempted to replicate those findings in a sample of community dwelling adults (N=211). The effect of Religious/Spiritual Involvement was mediated by Negative Beliefs about Alcohol, Social Modeling, and Spiritual-Well-Being. However, Social Modeling had stronger relationships with motives for drinking and alcohol consumption than the other two mediators. The effect of Religious Struggle on Alcohol Problems was mediated by Spiritual Well-Being and coping motives for drinking. Results provide further support for the motivational model of alcohol use and suggest plausible mechanisms by which religiousness could causally impact alcohol use and problems. Religious struggle may be a clinically significant correlate of alcohol problems. Copyright © 2011 Elsevier Ltd. All rights reserved.
Franko, Debra L; Fuller-Tyszkiewicz, Matthew; Rodgers, Rachel F; Holmqvist Gattario, Kristina; Frisén, Ann; Diedrichs, Phillippa C; Ricciardelli, Lina A; Yager, Zali; Smolak, Linda; Thompson-Brenner, Heather; Shingleton, Rebecca M
2015-09-01
We examined whether internalization of sociocultural body ideals mediated the relationship between conformity to masculine norms and drive for muscularity, leanness, and thinness in a sample of males from Sweden, US, UK, and Australia. Over six hundred young men [n=142 (Sweden); n=192 (US); n=141 (UK); n=160 (Australia)] completed an online survey that included assessments of masculine role norms, body image, and internalization of sociocultural body ideals. Path analyses confirmed internalization as a mediator between greater conformity to masculine norms and body image measures (drive for thinness, desire for leanness, and desire for muscularity) across the sample. However, significant cross-country differences in the strength of these mediation effects were found. Mediation effects among US, Australian, and Swedish males were comparable, whereas these effects were weaker in the UK sample. Findings confirmed the importance of internalization of sociocultural body ideals in the tested models. Copyright © 2015 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Miller, Byron; Taylor, John
2012-01-01
Stress research shows that race, socioeconomic status (SES), and family context significantly impact an adolescent's psychological well-being, yet little is known about the mediating effects of family context on racial and SES differences in depressive symptoms among Black and White youth. We investigate these associations using a sample of 875…
Socioeconomic position, health behaviors, and C-reactive protein: A moderated-mediation analysis
Kershaw, Kiarri N.; Mezuk, Briana; Abdou, Cleopatra M.; Rafferty, Jane A.; Jackson, James S.
2010-01-01
Objective We sought to understand the link between low SEP and cardiovascular disease (CVD) by examining the association between SEP, health-related coping behaviors, and C-reactive protein (CRP), an inflammatory marker and independent risk factor for CVD in a US sample of adults. Design We used a multiple mediation model to evaluate how these behaviors work in concert to influence CRP levels and whether these relationships were moderated by gender and race/ethnicity. Main outcome measures CRP levels were divided into two categories: elevated CRP (3.1–10.0 mg/L) and normal CRP (≤ 3.0 mg/L). Results Both poverty and low educational attainment were associated with elevated CRP, and these associations were primarily explained through higher levels of smoking and lower levels of exercise. In the education model, poor diet also emerged as a significant mediator. These behaviors accounted for 87.9% of the total effect of education on CRP and 55.8% the total effect of poverty on CRP. We also found significant moderation of these mediated effects by gender and race/ethnicity. Conclusion These findings demonstrate the influence of socioeconomically-patterned environmental constraints on individual-level health behaviors. Specifically, reducing socioeconomic inequalities may have positive effects on CVD disparities through reducing cigarette smoking and increasing vigorous exercise. PMID:20496985
Brief Integrative Multiple Behavior Intervention Effects and Mediators for Adolescents
(Chad) Werch, Chudley E.; Bian, Hui; Carlson, Joan; Moore, Michele J.; DiClemente, Carlo C.; Huang, I-Chan; Ames, Steven C.; Thombs, Dennis; Weiler, Robert M.; Pokorny, Steven B.
2015-01-01
This study evaluated the efficacy of a brief integrative multiple behavior intervention and assessed risk factors as mediators of behavioral outcomes among older adolescents. A randomized controlled trial was conducted with participants randomly assigned to either a brief intervention or standard care control with 3-month follow-up. A total of 479 students attending two public high schools participated. Participants receiving the intervention showed a significant reduction in quantity x frequency of alcohol use, and increases in fruit and vegetable consumption and frequency of relaxation activities, compared to those receiving the control, p’s =.01. No effects were found on cigarette and marijuana use, exercise and sleep. Effect sizes were small with alcohol use cessation effects reaching medium size. Intervention effects were mediated by changes in peer influenceability for alcohol use, and self-efficacy and self-image for health promoting behaviors. Findings suggest that the brief intervention resulted in health risk and promoting behavior improvements for adolescents, with outcomes mediated by several risk factors. PMID:20661637
Why childhood-onset type 1 diabetes impacts labour market outcomes: a mediation analysis.
Persson, Sofie; Dahlquist, Gisela; Gerdtham, Ulf-G; Steen Carlsson, Katarina
2018-02-01
Previous studies show a negative effect of type 1 diabetes on labour market outcomes such as employment and earnings later in life. However, little is known about the mechanisms underlying these effects. This study aims to analyse the mediating role of adult health, education, occupation and family formation. A total of 4179 individuals from the Swedish Childhood Diabetes Register and 16,983 individuals forming a population control group born between 1962 and 1979 were followed between 30 and 50 years of age. The total effect of having type 1 diabetes was broken down into a direct effect and an indirect (mediating) effect using statistical mediation analysis. We also analysed whether type 1 diabetes has different effects on labour market outcome between the sexes and across socioeconomic status. Childhood-onset type 1 diabetes had a negative impact on employment (OR 0.68 [95% CI 0.62, 0.76] and OR 0.76 [95% CI 0.67, 0.86]) and earnings (-6%, p < 0.001 and -8%, p < 0.001) for women and men, respectively. Each of the mediators studied contributed to the total effect with adult health and occupational field accounting for the largest part. However, some of the effect could not be attributed to any of the mediators studied and was therefore likely related to other characteristics of the disease that hamper career opportunities. The effect of type 1 diabetes on employment and earnings did not vary significantly according to socioeconomic status of the family (parental education and earnings). A large part of the effect of type 1 diabetes on the labour market is attributed to adult health but there are other important mediating factors that need to be considered to reduce this negative effect.
Schmidt, Stefanie J; Mueller, Daniel R; Roder, Volker
2011-09-01
Cognitive impairments are currently regarded as important determinants of functional domains and are promising treatment goals in schizophrenia. Nevertheless, the exact nature of the interdependent relationship between neurocognition and social cognition as well as the relative contribution of each of these factors to adequate functioning remains unclear. The purpose of this article is to systematically review the findings and methodology of studies that have investigated social cognition as a mediator variable between neurocognitive performance and functional outcome in schizophrenia. Moreover, we carried out a study to evaluate this mediation hypothesis by the means of structural equation modeling in a large sample of 148 schizophrenia patients. The review comprised 15 studies. All but one study provided evidence for the mediating role of social cognition both in cross-sectional and in longitudinal designs. Other variables like motivation and social competence additionally mediated the relationship between social cognition and functional outcome. The mean effect size of the indirect effect was 0.20. However, social cognitive domains were differentially effective mediators. On average, 25% of the variance in functional outcome could be explained in the mediation model. The results of our own statistical analysis are in line with these conclusions: Social cognition mediated a significant indirect relationship between neurocognition and functional outcome. These results suggest that research should focus on differential mediation pathways. Future studies should also consider the interaction with other prognostic factors, additional mediators, and moderators in order to increase the predictive power and to target those factors relevant for optimizing therapy effects.
Optical Fluorescent Imaging to Monitor Temporal Effects of Microbubble-Mediated Ultrasound Therapy
Sorace, Anna G.; Saini, Reshu; Rosenthal, Eben; Warram, Jason M.; Zinn, Kurt R.; Hoyt, Kenneth
2013-01-01
Microbubble-mediated ultrasound therapy can noninvasively enhance drug delivery to localized regions in the body. This technique can be beneficial in cancer therapy, but currently there are limitations to tracking the therapeutic effects. The purpose of this experiment was to investigate the potential of fluorescent imaging for monitoring the temporal effects of microbubble-mediated ultrasound therapy. Mice were implanted with 2LMP breast cancer cells. The animals underwent microbubble-mediated ultrasound therapy in the presence of Cy5.5 fluorescent-labeled IgG antibody (large molecule) or Cy5.5 dye (small molecule) and microbubble contrast agents. Control animals were administered fluorescent molecules only. Animals were transiently imaged in vivo at 1, 10, 30, and 60 min post therapy using a small animal optical imaging system. Tumors were excised and analyzed ex vivo. Tumors were homogenized and emulsion imaged for Cy5.5 fluorescence. Monitoring in vivo results showed significant influx of dye into the tumor (p < 0.05) using the small molecule, but not in the large molecule group (p > 0.05). However, after tumor emulsion, significantly higher dye concentration was detected in therapy group tumors for both small and large molecule groups in comparison to their control counterparts (p < 0.01). This paper explores a noninvasive optical imaging method for monitoring the effects of microbubble-mediated ultrasound therapy in a cancer model. It provides temporal information following the process of increasing extravasation of molecules into target tumors. PMID:23357902
Optical fluorescent imaging to monitor temporal effects of microbubble-mediated ultrasound therapy.
Sorace, Anna G; Saini, Reshu; Rosenthal, Eben; Warram, Jason M; Zinn, Kurt R; Hoyt, Kenneth
2013-02-01
Microbubble-mediated ultrasound therapy can noninvasively enhance drug delivery to localized regions in the body. This technique can be beneficial in cancer therapy, but currently there are limitations to tracking the therapeutic effects. The purpose of this experiment was to investigate the potential of fluorescent imaging for monitoring the temporal effects of microbubble-mediated ultrasound therapy. Mice were implanted with 2LMP breast cancer cells. The animals underwent microbubble-mediated ultrasound therapy in the presence of Cy5.5 fluorescent-labeled IgG antibody (large molecule) or Cy5.5 dye (small molecule) and microbubble contrast agents. Control animals were administered fluorescent molecules only. Animals were transiently imaged in vivo at 1, 10, 30, and 60 min post therapy using a small animal optical imaging system. Tumors were excised and analyzed ex vivo. Tumors were homogenized and emulsion imaged for Cy5.5 fluorescence. Monitoring in vivo results showed significant influx of dye into the tumor (p < 0.05) using the small molecule, but not in the large molecule group (p > 0.05). However, after tumor emulsion, significantly higher dye concentration was detected in therapy group tumors for both small and large molecule groups in comparison to their control counterparts (p <0.01). This paper explores a noninvasive optical imaging method for monitoring the effects of microbubble-mediated ultrasound therapy in a cancer model. It provides temporal information following the process of increasing extravasation of molecules into target tumors.
Forssmann, Ulf; Stoetzer, Carsten; Stephan, Michael; Kruschinski, Carsten; Skripuletz, Thomas; Schade, Jutta; Schmiedl, Andreas; Pabst, Reinhard; Wagner, Leona; Hoffmann, Torsten; Kehlen, Astrid; Escher, Sylvia E; Forssmann, Wolf-Georg; Elsner, Jörn; von Hörsten, Stephan
2008-07-15
Chemokines mediate the recruitment of leukocytes to the sites of inflammation. N-terminal truncation of chemokines by the protease dipeptidyl peptidase IV (DPPIV) potentially restricts their activity during inflammatory processes such as allergic reactions, but direct evidence in vivo is very rare. After demonstrating that N-terminal truncation of the chemokine CCL11/eotaxin by DPPIV results in a loss of CCR3-mediated intracellular calcium mobilization and CCR3 internalization in human eosinophils, we focused on the in vivo role of CCL11 and provide direct evidence for specific kinetic and rate-determining effects by DPPIV-like enzymatic activity on CCL11-mediated responses of eosinophils. Namely, it is demonstrated that i.v. administration of CCL11 in wild-type F344 rats leads to mobilization of eosinophils into the blood, peaking at 30 min. This mobilization is significantly increased in DPPIV-deficient F344 rats. Intradermal administration of CCL11 is followed by a dose-dependent recruitment of eosinophils into the skin and is significantly more effective in DPPIV-deficient F344 mutants as well as after pharmacological inhibition of DPPIV. Interestingly, CCL11 application leads to an up-regulation of DPPIV, which is not associated with negative feedback inhibition via DPPIV-cleaved CCL11((3-74)). These findings demonstrate regulatory effects of DPPIV for the recruitment of eosinophils. Furthermore, they illustrate that inhibitors of DPPIV have the potential to interfere with chemokine-mediated effects in vivo including but not limited to allergy.
Wang, Yan; Chen, Xinguang
2015-01-01
Objective Little research has been done on alcohol use and dependence among rural residents in China, a sub-population that might be under increased stress due to the rapid modernization and urbanization processes. We aimed to assess rural residents’ levels of stress, negative emotions, resilience, alcohol use/dependence and the complex relationships among them. Methods Survey data from a large random sample (n = 1145, mean age = 35.9, SD = 7.7, 50.7% male) of rural residents in Wuhan, China were collected using Audio Computer-Assisted Self-Interview. Results The sample had high prevalence of frequently perceived stress (47%) and high prevalence of ever (54.4%), past 30-day (40.4%), and binge drinking (13.8%). Approximately 11% met the criterion for intermediate to severe alcohol dependence. Mediation analysis indicated that the association between perceived stress (predictor) and alcohol dependence (outcome) was fully mediated by anxiety (indirect effect = .203, p < .01) and depression (indict effect =.158, p < .05); moderation analysis indicated that association between stress and two negative emotions (mediators) was significantly modified by resilience (moderator); an integrative moderated mediation analysis indicated that the indirect effect from stress to alcohol dependence through negative emotions was also moderated by resilience. Conclusions Negative emotions play a key role in bridging stress and alcohol dependence, while resilience significantly buffers the impact of stress on depression, reducing the risk of alcohol dependence. Resilience training may be an effective component for alcohol intervention in rural China. PMID:26342628
Adam, Liana; Black, Peter C; Kassouf, Wassim; Eve, Beryl; McConkey, David; Munsell, Mark F; Benedict, William F; Dinney, Colin P N
2007-05-01
Intravesical adenovirus mediated interferon-alpha gene transfer has a potent therapeutic effect against superficial human bladder carcinoma xenografts growing in the bladder of athymic nude mice. We determined whether the inhibition of angiogenesis might contribute to the antitumor effect. We treated several human urothelial carcinoma cells with adenovirus mediated interferon-alpha 2b and monitored its effects on the production of angiogenic factors using real-time reverse-transcription polymerase chain reaction, Western blotting, and immunohistochemical analysis and a gel shift based transcription factor array. To assess the role of adenovirus mediated interferon 2b in angiogenic activity we used in vitro invasion assays and evaluated the anti-angiogenic effects of adenovirus mediated interferon gene therapy in an orthotopic murine model of human superficial bladder cancer. In adenovirus mediated interferon-alpha infected 253J B-V cells vascular endothelial growth factor was decreased and anti-angiogenic interferon-gamma inducible protein 10 was up-regulated. In contrast, the addition of as much as 100,000 IU recombinant interferon had no apparent effect on vascular endothelial growth factor production. Conditioned medium derived from adenovirus mediated interferon 2b infected 253J B-V cells greatly decreased the invasive potential of human endothelial cells and down-regulated their matrix metalloproteinase 2 expression compared to controls. Furthermore, adenovirus mediated interferon 2b blocked pro-angiogenic nuclear signals, such as the transcription factors activating protein-1 and 2, stimulating protein-1, nuclear factor kappaB and c-myb. In vivo experiments revealed significant vascular endothelial growth factor down-regulation and decreased tumor vessel density in the adenovirus mediated interferon 2b treated group compared to controls. Treatment with adenovirus mediated interferon 2b increases the angiostatic activity of the bladder cancer microenvironment. This inhibition may prove beneficial for treating superficial bladder cancer with adenovirus mediated interferon-alpha and hopefully contribute to a decreased recurrence rate of this neoplasm.
Mechanisms of motivational interviewing in health promotion: a Bayesian mediation analysis
2012-01-01
Background Counselor behaviors that mediate the efficacy of motivational interviewing (MI) are not well understood, especially when applied to health behavior promotion. We hypothesized that client change talk mediates the relationship between counselor variables and subsequent client behavior change. Methods Purposeful sampling identified individuals from a prospective randomized worksite trial using an MI intervention to promote firefighters’ healthy diet and regular exercise that increased dietary intake of fruits and vegetables (n = 21) or did not increase intake of fruits and vegetables (n = 22). MI interactions were coded using the Motivational Interviewing Skill Code (MISC 2.1) to categorize counselor and firefighter verbal utterances. Both Bayesian and frequentist mediation analyses were used to investigate whether client change talk mediated the relationship between counselor skills and behavior change. Results Counselors’ global spirit, empathy, and direction and MI-consistent behavioral counts (e.g., reflections, open questions, affirmations, emphasize control) significantly correlated with firefighters’ total client change talk utterances (rs = 0.42, 0.40, 0.30, and 0.61, respectively), which correlated significantly with their fruit and vegetable intake increase (r = 0.33). Both Bayesian and frequentist mediation analyses demonstrated that findings were consistent with hypotheses, such that total client change talk mediated the relationship between counselor’s skills—MI-consistent behaviors [Bayesian mediated effect: αβ = .06 (.03), 95% CI = .02, .12] and MI spirit [Bayesian mediated effect: αβ = .06 (.03), 95% CI = .01, .13]—and increased fruit and vegetable consumption. Conclusion Motivational interviewing is a resource- and time-intensive intervention, and is currently being applied in many arenas. Previous research has identified the importance of counselor behaviors and client change talk in the treatment of substance use disorders. Our results indicate that similar mechanisms may underlie the effects of MI for dietary change. These results inform MI training and application by identifying those processes critical for MI success in health promotion domains. PMID:22681874
Annesi, James J; Mareno, Nicole; McEwen, Kristin L
2016-12-01
High emotional eating (EE) is prevalent in women with obesity. A previous study's subsample of obese women classified as high emotional eaters participated in either a physical activity-focused experimental (n = 29) or an educationally focused comparison (n = 22) behavioral treatment and was assessed over phases of expected weight loss (baseline-month 6) and short- and long-term regain (months 6-12 and 6-24, respectively). The study's aim was to assess theory-based psychological and behavioral mediation and moderation of changes in nutritional behaviors via emotional eating change in order to inform behavioral weight-loss treatments. During the weight-loss phase, significant improvements in eating self-regulation and mood significantly mediated the relationship of reduced EE and intake of both fruits and vegetables (FV) and sweets. Self-regulation was a significant independent mediator. Physical activity significantly moderated the relationship between EE and self-regulation changes. All variables demonstrated large positive effects and significant time × group interactions favoring the experimental group. During the short and long-term phases of expected weight regain, there were no significant changes in FV intake, although consumption of sweets significantly increased during months 6-24. Change in FV and sweets significantly predicted weight change, which was significantly greater in the experimental vs. comparison group over both the initial 6 months (-6.1% vs. -2.6%) and full 24 months of the study (-7.6% vs. -1.3%). Findings suggest that behavioral treatments should address EE through improvements in self-regulation and mood, and supported physical activity will aid in that process. The need for an improved understanding of weight-loss maintenance remains. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.
Flavonoids from Theobroma cacao down-regulate inflammatory mediators.
Ramiro, Emma; Franch, Angels; Castellote, Cristina; Pérez-Cano, Francisco; Permanyer, Joan; Izquierdo-Pulido, Maria; Castell, Margarida
2005-11-02
In the present study, we report the effects of a cocoa extract on the secretion and RNA expression of various proinflammatory mediators by macrophages. Monocyte chemoattractant protein 1 and tumor necrosis factor alpha (TNFalpha) were significantly and dose-dependently diminished by cocoa extract, and this effect was higher than that produced by equivalent concentrations of epicatechin but was lower than that produced by isoquercitrin. Interestingly, cocoa extract added prior to cell activation resulted in a significantly greater inhibition of TNFalpha secretion. Both cocoa extract and epicatechin decreased TNFalpha, interleukin (IL) 1alpha, and IL-6 mRNA expression, suggesting that their inhibitory effect on cytokine secretion is produced, in part, at the transcriptional level. Cocoa extract also significantly decreased NO secretion in a dose-dependent manner and with a greater effect than that produced by epicatechin. In conclusion, our study shows that cocoa flavonoids not only inhibit NO release from macrophages but also down-regulate inflammatory cytokines and chemokines.
Zhu, Shijun; Nahm, Eun-Shim; Resnick, Barbara; Friedmann, Erika; Brown, Clayton; Park, Jumin; Cheon, Jooyoung; Park, DoHwan
2017-07-01
This secondary data analyses of a longitudinal study assessed whether self-efficacy for exercise (SEE) mediated online intervention effects on exercise among older adults and whether age (50-64 vs. ≥65 years) moderated the mediation. Data were from an online bone health intervention study. Eight hundred sixty-six older adults (≥50 years) were randomized to three arms: Bone Power (n = 301), Bone Power Plus (n = 302), or Control (n = 263). Parallel process latent growth curve modeling (LGCM) was used to jointly model growths in SEE and in exercise and to assess the mediating effect of SEE on the effect of intervention on exercise. SEE was a significant mediator in 50- to 64-year-old adults (0.061, 95 BCI: 0.011, 0.163) but not in the ≥65 age group (-0.004, 95% BCI: -0.047, 0.025). Promotion of SEE is critical to improve exercise among 50- to 64-year-olds.
Stice, Eric; Marti, C Nathan; Rohde, Paul; Shaw, Heather
2011-06-01
Test the hypothesis that reductions in thin-ideal internalization and body dissatisfaction mediate the effects of a dissonance-based eating disorder prevention program on reductions in eating disorder symptoms over 1-year follow-up. Data were drawn from a randomized effectiveness trial in which 306 female high school students (mean age = 15.7 years, SD = 1.1) with body image concerns were randomized to the 4-session dissonance-based prevention program or an educational brochure control condition, wherein school counselors and nurses were responsible for participant recruitment and intervention delivery. Dissonance-intervention participants showed greater reductions in thin-ideal internalization, body dissatisfaction, and eating disorder symptoms; change in thin-ideal internalization predicted change in body dissatisfaction and symptoms; change in body dissatisfaction predicted change in symptoms; and all indirect effects were significant. Change in thin-ideal internalization fully mediated the effects of intervention condition on change in body dissatisfaction and partially mediated the effects on symptoms; change in body dissatisfaction partially mediated the effect of intervention condition on change in symptoms. Findings provided support for the intervention theory of this eating disorder prevention program over longer term follow-up, extending the evidence base for this effective intervention. (PsycINFO Database Record (c) 2011 APA, all rights reserved).
Stice, Eric; Marti, C. Nathan; Rohde, Paul; Shaw, Heather
2011-01-01
Objective Test the hypothesis that reductions in thin-ideal internalization and body dissatisfaction mediate the effects of a dissonance-based eating disorder prevention program on reductions in eating disorder symptoms over 1-year follow-up. Method Data were drawn from a randomized effectiveness trial in which 306 female high school students (M age = 15.7 SD = 1.1) with body image concerns were randomized to the 4-session dissonance-based prevention program or an educational brochure control condition, wherein school counselors and nurses were responsible for participant recruitment and intervention delivery. Results Dissonance participants showed greater reductions in thin-ideal internalization, body dissatisfaction, and eating disorder symptoms; change in thin-ideal internalization predicted change in body dissatisfaction and symptoms; change in body dissatisfaction predicted change in symptoms; and all indirect effects were significant. Change in thin-ideal internalization fully mediated the effects of intervention condition on change in body dissatisfaction and partially mediated the effects on symptoms; change in body dissatisfaction partially mediated the effect of intervention condition on change in symptoms. Conclusions Findings provided support for the intervention theory of this eating disorder prevention program over longer-term follow-up, extending the evidence base for this effective intervention. PMID:21500884
Mediators of Psychological Well-being in Adolescent Boys.
Lubans, David R; Smith, Jordan J; Morgan, Philip J; Beauchamp, Mark R; Miller, Andrew; Lonsdale, Chris; Parker, Philip; Dally, Kerry
2016-02-01
The aim of this study was to explore the effect of the Active Teen Leaders Avoiding Screen-time (ATLAS) intervention on psychological well-being in adolescent boys and to examine the potential mediating mechanisms that might explain this effect. ATLAS was evaluated using a cluster randomized controlled trial in 14 secondary schools located in low-income communities (N = 361 adolescent boys, mean age = 12.7 ± .5 years). The 20-week intervention was guided by self-determination theory and involved: professional development for teachers, provision of fitness equipment to schools, enhanced school sport sessions, researcher-led seminars, a smartphone application, and parental strategies for reducing screen time. Assessments were conducted at baseline and immediately post intervention (8 months). Psychological well-being was measured using the Flourishing Scale. Motivational regulations (intrinsic, identified, introjected, controlled, and amotivation) and basic psychological needs (autonomy, competence, and relatedness) in school sport, muscular fitness, resistance training skill competency, and recreational screen time were examined as potential mediating mechanisms of the intervention effect. The intervention effect on well-being was small but statistically significant. Within a multiple mediator model, changes in autonomy needs satisfaction, recreational screen time, and muscular fitness significantly mediated the effect of the intervention on psychological well-being. In addition to the physical health benefits, targeted physical activity programs for adolescent boys may have utility for mental health promotion through the mechanisms of increasing autonomy support and muscular fitness and reducing screen time. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
Living with disability: patterns of health problems and symptom mediation of health consequences.
Patterson, Brandon J; Doucette, William R; Lindgren, Scott D; Chrischilles, Elizabeth A
2012-07-01
People with disability experience a range of symptoms that may serve as an important linkage between disability and other health consequences. The aims of this study were to describe and compare symptom experiences of people with and without disability using a population-based sample and to test direct relationships between disability and health status and indirect effects of disability mediated through symptom experience. A Midwestern sample of 12,249 adults aged 40 and older responded to a cross-sectional survey. Data collected included symptom prevalence and frequencies for 21 commonly reported symptoms, self-perceived health status and physical functioning, number of medications, and demographic variables. Two mediation analyses were conducted using cumulative symptom frequency as the mediator between disability status and both self-rated health and physical functioning. Adults with disability reported significantly greater prevalence and frequencies for all 21 symptoms, with pain and fatigue being the most common. The indirect effect through cumulative symptom frequency explained roughly half of the total effect of disability on general health status, and about one third of the total effect of disability on physical functioning. This study found evidence supporting the diverse and significant symptom experience of people living with disability, especially for symptoms of pain and fatigue. Moreover, symptom experience was found to partially mediate the effects of disability on self-reported general health status and physical functioning. This provides support for symptoms serving as an important link to health outcomes in patients with disability. Copyright © 2012 Elsevier Inc. All rights reserved.
Yang, Chun; Xiong, Wei; Qiu, Qian; Shao, Zhuo; Shao, Zuo; Hamel, David; Tahiri, Houda; Leclair, Grégoire; Lachapelle, Pierre; Chemtob, Sylvain; Hardy, Pierre
2012-04-15
Microparticles possess therapeutic potential regarding angiogenesis. We have demonstrated the contribution of apoptotic human CEM T lymphocyte-derived microparticles (LMPs) as inhibitors of angiogenic responses in animal models of inflammation and tumor growth. In the present study, we characterized the antivascular endothelial growth factor (VEGF) effects of LMPs on pathological angiogenesis in an animal model of oxygen-induced retinopathy and explored the role of receptor-mediated endocytosis in the effects of LMPs on human retinal endothelial cells (HRECs). LMPs dramatically inhibited cell growth of HRECs, suppressed VEGF-induced cell migration in vitro experiments, and attenuated VEGF-induced retinal vascular leakage in vivo. Intravitreal injections of fluorescently labeled LMPs revealed accumulation of LMPs in retinal tissue, with more than 60% reductions of the vascular density in retinas of rats with oxygen-induced neovascularization. LMP uptake experiments demonstrated that the interaction between LMPs and HRECs is dependent on temperature. In addition, endocytosis is partially dependent on extracellular calcium. RNAi-mediated knockdown of low-density lipoprotein receptor (LDLR) reduced the uptake of LMPs and attenuated the inhibitory effects of LMPs on VEGF-A protein expression and HRECs cell growth. Intravitreal injection of lentivirus-mediated RNA interference reduced LDLR protein expression in retina by 53% and significantly blocked the antiangiogenic effects of LMPs on pathological vascularization. In summary, the potent antiangiogenic LMPs lead to a significant reduction of pathological retinal angiogenesis through modulation of VEGF signaling, whereas LDLR-mediated endocytosis plays a partial, but pivotal, role in the uptake of LMPs in HRECs.
Trudel, Xavier; Brisson, Chantal; Milot, Alain; Masse, Benoit; Vézina, Michel
2016-11-01
A number of prospective studies have documented the effect of adverse psychosocial work factors (work stress) on high blood pressure (BP). Weight gain could be an important pathway by which work stress exerts its effect on BP. No previous prospective study has examined this mediating effect. The aim of the present study was to examine the mediating effect of body mass index (BMI) in the association between psychosocial work factors from Siegrist's effort-reward imbalance model (ERI) and ambulatory BP (ABP). A prospective study was conducted among 1436 white-collar workers. Data were collected three times during a 5-year period. ERI was measured using validated scales, at each time. BMI was measured by a trained assistant. ABP was measured every 15 min during a working day. ERI exposure onset over 3 years was indirectly associated with ABP changes (0.49 mmHg; 95 % CI 0.05, 1.22), through BMI changes, in women with baseline BMI ≥25 kg/m 2 . An effect of similar magnitude and of borderline significance was observed for ERI chronic exposure. No mediating effect was observed among men, and using ERI exposure over 5 years. The mediating effect of BMI was of small magnitude and observed in certain subgroups and time frame only. Subgroup-specific mediating pathways might be involved to explain the effect of work stress on cardiovascular diseases risk.
Identifying Sources of Clinical Conflict: A Tool for Practice and Training in Bioethics Mediation.
Bergman, Edward J
2015-01-01
Bioethics mediators manage a wide range of clinical conflict emanating from diverse sources. Parties to clinical conflict are often not fully aware of, nor willing to express, the true nature and scope of their conflict. As such, a significant task of the bioethics mediator is to help define that conflict. The ability to assess and apply the tools necessary for an effective mediation process can be facilitated by each mediator's creation of a personal compendium of sources that generate clinical conflict, to provide an orientation for the successful management of complex dilemmatic cases. Copyright 2015 The Journal of Clinical Ethics. All rights reserved.
Sui, Feng; Zhou, Hai-Yu; Meng, Jing; Du, Xin-Liang; Sui, Yun-Peng; Zhou, Zhi-Kun; Dong, Cheng; Wang, Zhu-Ju; Wang, Wei-Hao; Dai, Li; Ma, Hai; Huo, Hai-Ru; Jiang, Ting-Liang
2016-01-01
Shaoyao-Gancao Tang (SGT) is one of the most frequently used compound formulas in the treatment of pain-related diseases in the medical practice of traditional Chinese medicine (TCM). To investigate the anti-inflammatory and antinociceptive effects, as well as to uncover the molecular mechanism of SGT, the rat pain model of arthritis was experimentally induced by single unilateral injection of rats' left hind paw with Freund's complete adjuvant (FCA). SGT was orally administered to the rats daily at three doses individually for a period of 16 days post-model induction. Swollen degrees and pain thresholds of the rats in different groups were measured for evaluation of the anti-inflammatory and anti-nociceptive effects of SGT. Furthermore, the mRNA and protein expression levels of transient receptor potential ion channel protein vanilloid receptor 1 (TRPV1) channel as well as its calcium-mediating function in the isolated DRG neurons were further detected to provide indexes for exploration of the molecular mechanisms mediating anti-arthritic activities of SGT. As a result, FCA injection induced significant allodynia, inflammation and edema, accompanied by a significant increase in both expression and calcium-mediating function of the TRPV1 channel. Pharmacologically, oral administration of SGT at a high or middle dose demonstrated a significant relief from the above-mentioned pathological conditions in a dose-dependent manner. Simultaneously the mRNA and protein expressional levels of TRPV1 channel, as well as its calcium-mediating function, were down-regulated greatly. These findings suggest that SGT possesses a significant analgesic and anti-inflammatory effect on arthritis rats; its therapeutic activities might be achieved through reversing the elevated expression and function of TRPV1 channel evoked by FCA.
Lévesque, Annie; Campbell, Aimee N C; Pavlicova, Martina; Hu, Mei-Chen; Walker, Robrina; McClure, Erin A; Ghitza, Udi E; Bailey, Genie; Stitzer, Maxine; Nunes, Edward V
2017-02-01
Coping strategies are a predictor of abstinence among patients with substance use disorders. However, little is known regarding the role of coping strategies in the effectiveness of the Community Reinforcement Approach (CRA). Using data from a 12week randomized control trial assessing the effectiveness of the Therapeutic Education System (TES), an internet-delivered version of the CRA combined with contingency management, we tested the role of coping strategies as a mediator of treatment effectiveness. 507 participants entering 10 outpatient addiction treatment programs received either treatment-as-usual (TAU), a counselor-delivered treatment (Arm 1), or reduced TAU plus TES wherein 2h of TAU per week were replaced by TES (Arm 2). Abstinence from drugs and alcohol was evaluated using urine toxicology and self-report. Coping strategies were measured using the Coping Strategies Scale-Brief Version. Mediation analyses were done following Baron and Kenny's and path analysis approaches. The average baseline coping strategies scores were not significantly different between the two treatment arms. Overall, TES intervention was significantly associated with higher coping strategies scores when accounting for baseline scores (F 1,1342 =8.3, p=0.004). Additionally, higher coping strategies scores at week 12 were associated with an increased likelihood of abstinence during the last 4weeks of the treatment, while accounting for treatment assignment and baseline abstinence. The effect of TES intervention on abstinence was no longer significant after controlling for coping strategies scores at week 12. Our results support the importance of coping skills as a partial mediator of the effectiveness of an internet-version of the CRA combined with contingency management. Copyright © 2016. Published by Elsevier Ltd.
Kohrt, Brandon A.; Speckman, Rebecca A.; Kunz, Richard D.; Baldwin, Jennifer L.; Upadhaya, Nawaraj; Acharya, Nanda Raj; Sharma, Vidya Dev; Nepal, Mahendra K.; Worthman, Carol M.
2013-01-01
Background The causes of ethnic and caste-based disparities in mental health are poorly understood. Aim To identify mediators underlying caste-based disparities in mental health in Nepal. Subjects and methods A mixed methods ethnographic and epidemiological study of 307 adults (Dalit/Nepali, n=75; high caste Brahman and Chhetri, n=232) assessed with Nepali versions of Beck Depression (BDI) and Anxiety (BAI) Inventories. Results One third (33.7%) of participants were classified as depressed: Dalit/Nepali 50.0%, high caste 28.4%. One quarter (27.7%) of participants were classified as anxious: Dalit/Nepali 50.7%, high caste 20.3%. Ethnographic research identified four potential mediators: stressful life events, owning few livestock, no household income, and lack of social support. The direct effect of caste was 1.08 (95% CI -1.10—3.27) on depression score and 4.76 (95% CI 2.33—7.19) on anxiety score. All four variables had significant indirect (mediation) effects on anxiety, and all but social support had significant indirect effects on depression. Conclusion Caste-based disparities in mental health in rural Nepal are statistically mediated by poverty, lack of social support, and stressful life events. Interventions should target these areas to alleviate the excess mental health burden born by Dalit/Nepali women and men. PMID:19381985
Kohrt, Brandon A; Speckman, Rebecca A; Kunz, Richard D; Baldwin, Jennifer L; Upadhaya, Nawaraj; Acharya, Nanda Raj; Sharma, Vidya Dev; Nepal, Mahendra K; Worthman, Carol M
2009-01-01
The causes of ethnic and caste-based disparities in mental health are poorly understood. The study aimed to identify mediators underlying caste-based disparities in mental health in Nepal. A mixed methods ethnographic and epidemiological study of 307 adults (Dalit/Nepali, n=75; high caste Brahman and Chhetri, n=232) was assessed with Nepali versions of Beck Depression (BDI) and Anxiety (BAI) Inventories. One-third (33.7%) of participants were classified as depressed: Dalit/Nepali 50.0%, high caste 28.4%. One quarter (27.7%) of participants were classified as anxious: Dalit/Nepali 50.7%, high caste 20.3%. Ethnographic research identified four potential mediators: Stressful life events, owning few livestock, no household income, and lack of social support. The direct effect of caste was 1.08 (95% CI -1.10-3.27) on depression score and 4.76 (95% CI 2.33-7.19) on anxiety score. All four variables had significant indirect (mediation) effects on anxiety, and all but social support had significant indirect effects on depression. Caste-based disparities in mental health in rural Nepal are statistically mediated by poverty, lack of social support, and stressful life events. Interventions should target these areas to alleviate the excess mental health burden born by Dalit/Nepali women and men.
Schairer, Catherine; Fuhrman, Barbara J; Boyd-Morin, Jennifer; Genkinger, Jeanine M; Gail, Mitchell H; Hoover, Robert N; Ziegler, Regina G
2016-01-01
Higher body mass index (BMI) and circulating estrogen levels each increase postmenopausal breast cancer risk, particularly estrogen receptor-positive (ER(+)) tumors. Higher BMI also increases estrogen production. We estimated the proportion of the BMI-ER(+) breast cancer association mediated through estrogen in a case-control study nested within the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Participants included 143 women with invasive ER(+) breast cancer and 268 matched controls, all postmenopausal and never having used hormone therapy at baseline. We used liquid chromatography-tandem mass spectrometry to measure 15 estrogens and estrogen metabolites in baseline serum. We calculated BMI from self-reported height and weight at baseline. We estimated the mediating effect of unconjugated estradiol on the BMI-ER(+) breast cancer association using Aalen additive hazards and Cox regression models. All estrogens and estrogen metabolites were statistically significantly correlated with BMI, with unconjugated estradiol most strongly correlated [Pearson correlation (r) = 0.45]. Approximately 7% to 10% of the effect of overweight, 12% to 15% of the effect of obesity, and 19% to 20% of the effect of a 5 kg/m(2) BMI increase on ER(+) breast cancer risk was mediated through unconjugated estradiol. The BMI-breast cancer association, once adjusted for unconjugated estradiol, was not modified by further adjustment for two metabolic ratios statistically significantly associated with both breast cancer and BMI. Circulating unconjugated estradiol levels partially mediate the BMI-breast cancer association, but other potentially important estrogen mediators (e.g., bioavailable estradiol) were not evaluated. Further research is required to identify mechanisms underlying the BMI-breast cancer association. ©2015 American Association for Cancer Research.
Zhang, Ruowen; Che, Xun; Zhang, Jingjie; Li, Yang; Li, Jingxia; Deng, Xu; Zhu, Junlan; Jin, Honglei; Zhao, Qinshi; Huang, Chuanshu
2016-10-11
Cheliensisin A (Chel A), a styryl-lactone compound extracted from Goniothalamus cheliensis, is reported to have significant anti-cancer effects in various cancer cells. Here we demonstrated that Chel A treatment resulted in apoptosis and an inhibition of anchorage-independent growth in human bladder cancer T24, T24T and U5637 cells. Mechanistic studies showed that such effect is mediated by PH domain and Leucine rich repeat Protein Phosphatases (PHLPP2) protein. Chel A treatment led to PHLPP2 degradation and subsequently increased in c-Jun phosphorylation. Moreover PHLPP2 degradation could be attenuated by inhibition of autophagy, which was mediated by Beclin 1. Collectively, we discover that Chel A treatment induces Beclin-dependent autophagy, consequently mediates PHLPP2 degradation and JNK/C-Jun phosphorylation and activation, further in turn contributing to apoptosis in human bladder cancer cells. Current studies provide a significant insight into understanding of anticancer effect of Chel A in treatment of human bladder cancer.
Li, Yang; Li, Jingxia; Deng, Xu; Zhu, Junlan; Jin, Honglei; Zhao, Qinshi; Huang, Chuanshu
2016-01-01
Cheliensisin A (Chel A), a styryl-lactone compound extracted from Goniothalamus cheliensis, is reported to have significant anti-cancer effects in various cancer cells. Here we demonstrated that Chel A treatment resulted in apoptosis and an inhibition of anchorage-independent growth in human bladder cancer T24, T24T and U5637 cells. Mechanistic studies showed that such effect is mediated by PH domain and Leucine rich repeat Protein Phosphatases (PHLPP2) protein. Chel A treatment led to PHLPP2 degradation and subsequently increased in c-Jun phosphorylation. Moreover PHLPP2 degradation could be attenuated by inhibition of autophagy, which was mediated by Beclin 1. Collectively, we discover that Chel A treatment induces Beclin-dependent autophagy, consequently mediates PHLPP2 degradation and JNK/C-Jun phosphorylation and activation, further in turn contributing to apoptosis in human bladder cancer cells. Current studies provide a significant insight into understanding of anticancer effect of Chel A in treatment of human bladder cancer. PMID:27556506
Reid, Allecia E; Carey, Kate B
2018-06-01
Level of drinking in the social network is strongly associated with college students' alcohol use. However, mechanisms through which networks are associated with personal drinking have been underexplored thus far. The present study examined theoretically derived constructs-sociability outcome expectancies, attitudes toward heavy drinking, self-efficacy for use of protective strategies, and descriptive norms-as potential mediators of the association between egocentric social network drinking and personal consumption. College students (N = 274) self-reported their social network's level of alcohol consumption, all mediators, drinks per week, and consequences at both baseline (Time 1) and a 1-month follow-up (Time 2). Autoregressive mediation models focused on the longitudinal associations between Time 1 network drinking and the Time 2 mediators and between the Time 1 mediators and the Time 2 outcomes. Consistent with hypotheses, Time 1 social network drinking was significantly associated with Time 2 drinks per week and consequences. Only attitudes significantly mediated social network associations with drinks per week and consequences, though the proportion of the total effects accounted for by attitudes was small. After accounting for the stability of constructs over time, social network drinking was generally un- or weakly related to sociability expectancies, self-efficacy, and descriptive norms. Results support reducing attitudes toward heavy drinking as a potential avenue for mitigating network effects, but also highlight the need to evaluate additional potential mechanisms of network effects. Intervention efforts that aim to address the social network have the potential to substantially reduce alcohol consumption, thereby enhancing the overall efficacy of alcohol risk-reduction interventions. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Lounibos, L. Philip; Nishimura, Naoya; Greene, Krystle
2010-01-01
Native predators are postulated to have an important role in biotic resistance of communities to invasion and community resilience. Effects of predators can be complex, and mechanisms by which predators affect invasion success and impact are understood for only a few well-studied communities. We tested experimentally whether a native predator limits an invasive species' success and impact on a native competitor for a community of aquatic insect larvae in water-filled containers. The native mosquito Aedes triseriatus alone had no significant effect on abundance of the invasive mosquito Aedes albopictus. The native predatory midge Corethrella appendiculata, at low or high density, significantly reduced A. albopictus abundance. This effect was not caused by trait-mediated oviposition avoidance of containers with predators, but instead was a density-mediated effect caused by predator-induced mortality. The presence of this predator significantly reduced survivorship of the native species, but high predator density also significantly increased development rate of the native species when the invader was present, consistent with predator-mediated release from interspecific competition with the invader. Thus, a native predator can indirectly benefit its native prey when a superior competitor invades. This shows the importance of native predators as a component of biodiversity for both biotic resistance to invasion and resilience of a community perturbed by successful invasion. PMID:19841945
Nootropic activity of tuber extract of Pueraria tuberosa (Roxb).
Rao, N Venkata; Pujar, Basavaraj; Nimbal, S K; Shantakumar, S M; Satyanarayana, S
2008-08-01
Nootropic effect of alcoholic (ALE; 50, 75, 100 mg/kg) and aqueous (AQE; 100, 200, 400 mg/kg) extracts of P. tuberosa was evaluated by using Elevated Plus Maze (EPM), scopolamine-induced amnesia (SIA), diazepam-induced amnesia (DIA), clonidine-induced (NA-mediated) hypothermia (CIH), lithium-induced (5-HT mediated) head twitches (LIH) and haloperidol-induced (DA- mediated) catalepsy (HIC) models. Piracetam was used as the standard drug. A significant increase in inflexion ratio (IR) was recorded in EPM, SIA and DIA models. A significant reversal effect was observed on rectal temperature in CIH model, reduction of head twitches in LIH models. However no significant reduction in catalepsy scores in HIC models were observed with test extracts and standard piracetam. The results indicate that nootropic activity observed with ALE and AQE of tuber extracts of P. tuberosa could be through improved learning and memory either by augmenting the noradrenaline (NA) transmission or by interfering with 5-hydroxytryptamine (5-HT) release. Further, the extracts neither facilitated nor blocked release of the dopamine (DA). Thus ALE and AQE elicited significant nootropic effect in mice and rats by interacting with cholinergic, GABAnergic, adrenergic and serotonergic systems. Phytoconstituents like flavonoids have been reported for their nootropic effect and these are present in both ALE and AQE extracts of tubers of P. tuberosa (Roxb) and these active principles may be responsible for nootropic activity.
Passion, Trait Self-Control, and Wellbeing: Comparing Two Mediation Models Predicting Wellbeing.
Briki, Walid
2017-01-01
Research has found that passion and trait self-control represented key determinants of wellbeing. Yet, no study to date has attempted to investigate the mediating influences of trait self-control and passion for accounting for the relationships between passion, trait self-control, and wellbeing (dependent variable). Using different frameworks, such as the dualistic model of passion and the neo-socioanalytic theory, the present study proposed two mediation models, considering either trait self-control (model 1) or passion (model 2) as the mediating variable. Five hundred nine volunteers from the United States (326 females and 183 males; M age = 31.74, SD age = 11.05, from 18 to 70 years old), who reported being passionate about a specific activity (e.g., fishing, swimming, blogging; M passion = 5.94, SD passion = 0.89), answered questionnaires assessing harmonious and obsessive passion, trait self-control, and wellbeing (measured through hedonic and eudaimonic wellbeing scales). Preliminary analyses revealed that both models were significant ( model 1: absolute GoF = 0.366, relative GoF = 0.971, outer model GoF = 0.997, inner model GoF = 0.973, R 2 = 18.300%, p < 0.001; model 2: absolute GoF = 0.298; relative GoF = 0.980; outer model GoF = 0.997; inner model GoF = 0.982; R 2 = 12.111%, p < 0.001). Correlational analyses revealed positive relationships between harmonious passion, trait self-control, and wellbeing, and no relationships of obsessive passion with trait self-control and wellbeing. Mediation analyses revealed that trait self-control significantly mediated the relationship between harmonious passion and wellbeing (i.e., partial mediation, VAF = 33.136%). Harmonious passion appeared to significantly mediate the positive effect of trait self-control on wellbeing; however, the size of the mediating effect indicated that (almost) no mediation would take place (i.e., VAF = 11.144%). The present study is the first to examine the relationships between passion, trait self-control, and wellbeing, and supports the view that trait self-control and harmonious passion represent not only adaptive and powerful constructs, but also key determinants of wellbeing. Implications for the study of passion, trait self-control and wellbeing are discussed.
Passion, Trait Self-Control, and Wellbeing: Comparing Two Mediation Models Predicting Wellbeing
Briki, Walid
2017-01-01
Research has found that passion and trait self-control represented key determinants of wellbeing. Yet, no study to date has attempted to investigate the mediating influences of trait self-control and passion for accounting for the relationships between passion, trait self-control, and wellbeing (dependent variable). Using different frameworks, such as the dualistic model of passion and the neo-socioanalytic theory, the present study proposed two mediation models, considering either trait self-control (model 1) or passion (model 2) as the mediating variable. Five hundred nine volunteers from the United States (326 females and 183 males; Mage = 31.74, SDage = 11.05, from 18 to 70 years old), who reported being passionate about a specific activity (e.g., fishing, swimming, blogging; Mpassion = 5.94, SDpassion = 0.89), answered questionnaires assessing harmonious and obsessive passion, trait self-control, and wellbeing (measured through hedonic and eudaimonic wellbeing scales). Preliminary analyses revealed that both models were significant (model 1: absolute GoF = 0.366, relative GoF = 0.971, outer model GoF = 0.997, inner model GoF = 0.973, R2 = 18.300%, p < 0.001; model 2: absolute GoF = 0.298; relative GoF = 0.980; outer model GoF = 0.997; inner model GoF = 0.982; R2 = 12.111%, p < 0.001). Correlational analyses revealed positive relationships between harmonious passion, trait self-control, and wellbeing, and no relationships of obsessive passion with trait self-control and wellbeing. Mediation analyses revealed that trait self-control significantly mediated the relationship between harmonious passion and wellbeing (i.e., partial mediation, VAF = 33.136%). Harmonious passion appeared to significantly mediate the positive effect of trait self-control on wellbeing; however, the size of the mediating effect indicated that (almost) no mediation would take place (i.e., VAF = 11.144%). The present study is the first to examine the relationships between passion, trait self-control, and wellbeing, and supports the view that trait self-control and harmonious passion represent not only adaptive and powerful constructs, but also key determinants of wellbeing. Implications for the study of passion, trait self-control and wellbeing are discussed. PMID:28611704
Strekalova, Yulia A
2018-02-01
Black participants remain significantly underrepresented in clinical research. Mistrust in medical researchers has been named a key barrier to the successful enrollment of minority study participants. However, trust is a social-interactional construct, and its effects on behavior are complex. This study hypothesized that intention to participate in clinical research is mediated by trust in medical researchers, eHealth literacy, and information seeking behavior. The data were collected through an online survey ( N = 340) and analyzed to identify serial mediation. The model showed insignificant direct effect of race identity on behavioral intention, c' = -0.19, t(335) = -1.22, p = .22, but a significant total effect, c = -0.44, t(335) = -2.59, p < .01. The indirect effect of race identity on behavioral intention was also significant. The positive effect of trust in medical researchers on decisions to participate in clinical research can be amplified by stronger eHealth literacy and active information seeking, which can be supported through focused strategic health education and communication interventions. A focus on the development of information literacy that could provide prospective minority research volunteers with skills for informed decision making should be explored as an option for increasing mindful, informed participation in clinical research among currently underrepresented racial and ethnic groups.
Zhu, Hong; Luo, Xingwei; Cai, Taisheng; Li, Zhihua; Liu, Wenli
2014-11-01
The study was conducted to simultaneously investigate the mediating effects of parental control and adolescents' self-control on the relationship between adolescents' negative emotions and emotional eating, and to determine pathways with the greatest effect among these variables. Negative emotions, emotional eating, parental control, and self-control were investigated in 594 high school students (average age=16.70, SD=1.09) in Changsha City, China. High levels of negative emotions and parental control and low levels of self-control were strongly related to high levels of emotional eating in adolescents. In addition to the direct relationship between negative emotions and emotional eating, there was a mediating effect observed through low self-control and high parental control. The mediational effect of parental control was non-significant in adolescent boys. Furthermore, negative emotions related to emotional eating through the effect of parental control on adolescents' self-control. The degree to which both mediators explained the relationship between negative emotions and emotional eating ranged from 52.6% to 66.8%, and self-control had a stronger mediational effect than did parental control. The results indicate that both self-control and parental control should be considered in designing preventative measures against emotional eating in adolescents. Adolescent self-control training could also assist in preventing emotional eating. Copyright © 2014 Elsevier Ltd. All rights reserved.
Xiaowen, Wang; Guangping, Guo; Ling, Zhou; Jiarui, Zheng; Xiumin, Liang; Zhaoqin, Li; Hongzhuan, Luo; Yuyan, Yang; Liyuan, Yang; Lin, Lu
2018-04-01
Pregnant women living with HIV represent one of the most high-priority groups for HIV treatment and health assessment. Although social support has been shown to be a protective factor for improved health-related quality of life (HRQoL), and depression and anxiety have been identified as two major causes of psychological distress among people living with HIV, it is still unclear how social support, anxiety, and depression interact to influence HRQoL. The objective of our study was to demonstrate the nature of predictors, direct effects and mediator effects among social support, anxiety, depression symptoms and HRQoL in pregnant women living with HIV. We investigated a total of 101 pregnant women living with HIV in Yunnan province in China from April 2016 to June 2016. All participants completed the Social Support Rating Scale (SSRS), the Chinese version of the Hospital Anxiety and Depression Scales (HADS) and Quality of Life instruments (EuroQoL Five Dimensions Questionnaire, EQ-5D). The relationships between the variables were examined by Pearson's or Spearman's correlation analysis. Predictor effects were tested using separate multiple regressions, controlling for demographic variables and HIV diagnosis variables. Direct and mediation effects of social support on HRQoL were tested using a structural equation model (SEM). Anxiety and depression symptoms were negatively correlated with subjective social support, support utilization, social support and HRQoL. Social support significantly predicted better HRQoL, and anxiety and depression symptoms significantly predicted poorer HRQoL. Anxiety and depression symptoms partially mediated the associations between social support and HRQoL. Anxiety and depression symptoms completely mediated the associations of objective support and support utilization with HRQoL. Interventions to improve HRQoL in pregnant women living with HIV must consider the mediation effect of anxiety and depression symptoms on the association between social support and HRQoL. Social support interventions are valid only when anxiety and depression symptoms are managed effectively.
Fernandez-Palomo, Cristian; McNeill, Fiona E.; Seymour, Colin B.; Rainbow, Andrew J.; Mothersill, Carmel E.
2017-01-01
Objective The objective of our study was to explore a possible molecular mechanism by which ultraviolet (UV) biophotons could elicit bystander responses in reporter cells and resolve the problem of seemingly mutually exclusive mechanisms of a physical UV signal & a soluble factor-mediated bystander signal. Methods The human colon carcinoma cell line, HCT116 p53 +/+, was directly irradiated with 0.5 Gy tritium beta particles to induce ultraviolet biophoton emission. Bystander cells were not directly irradiated but were exposed to the emitted UV biophotons. Medium was subsequently harvested from UV-exposed bystander cells. The exosomes extracted from this medium were incubated with reporter cell populations. These reporter cells were then assayed for clonogenic survival and mitochondrial membrane potential with and without prior treatment of the exosomes with RNase. Results Clonogenic cell survival was significantly reduced in reporter cells incubated with exosomes extracted from cells exposed to secondarily-emitted UV. These exosomes also induced significant mitochondrial membrane depolarization in receiving reporter cells. Conversely, exosomes extracted from non-UV-exposed cells did not produce bystander effects in reporter cells. The treatment of exosomes with RNase prior to their incubation with reporter cells effectively abolished bystander effects in reporter cells and this suggests a role for RNA in mediating the bystander response elicited by UV biophotons and their produced exosomes. Conclusion This study supports a role for exosomes released from UV biophoton-exposed bystander cells in eliciting bystander responses and also indicates a reconciliation between the UV-mediated bystander effect and the bystander effect which has been suggested in the literature to be mediated by soluble factors. PMID:28278290
Le, Michelle; Fernandez-Palomo, Cristian; McNeill, Fiona E; Seymour, Colin B; Rainbow, Andrew J; Mothersill, Carmel E
2017-01-01
The objective of our study was to explore a possible molecular mechanism by which ultraviolet (UV) biophotons could elicit bystander responses in reporter cells and resolve the problem of seemingly mutually exclusive mechanisms of a physical UV signal & a soluble factor-mediated bystander signal. The human colon carcinoma cell line, HCT116 p53 +/+, was directly irradiated with 0.5 Gy tritium beta particles to induce ultraviolet biophoton emission. Bystander cells were not directly irradiated but were exposed to the emitted UV biophotons. Medium was subsequently harvested from UV-exposed bystander cells. The exosomes extracted from this medium were incubated with reporter cell populations. These reporter cells were then assayed for clonogenic survival and mitochondrial membrane potential with and without prior treatment of the exosomes with RNase. Clonogenic cell survival was significantly reduced in reporter cells incubated with exosomes extracted from cells exposed to secondarily-emitted UV. These exosomes also induced significant mitochondrial membrane depolarization in receiving reporter cells. Conversely, exosomes extracted from non-UV-exposed cells did not produce bystander effects in reporter cells. The treatment of exosomes with RNase prior to their incubation with reporter cells effectively abolished bystander effects in reporter cells and this suggests a role for RNA in mediating the bystander response elicited by UV biophotons and their produced exosomes. This study supports a role for exosomes released from UV biophoton-exposed bystander cells in eliciting bystander responses and also indicates a reconciliation between the UV-mediated bystander effect and the bystander effect which has been suggested in the literature to be mediated by soluble factors.
Noh, Jin-Won; Park, Hyunchun; Kim, Minji; Kwon, Young Dae; Kim, Jin-Seok; Yu, Shieun
2018-01-01
This study investigated the mediation effect of stress between the experience of discrimination and life satisfaction among North Korean refugees who resettled in South Korea. The findings of the current study provide empirical evidence for the need of social interventions to mitigate adverse effects of stress on North Korean refugees who are subject to social discrimination on a daily basis. In this study, we included 500 subjects among 2,138 North Korean refugees who took refuge in South Korea in 2007. The interview started from April 6th 2009 and finished on May 25th 2009. We conducted moderator effect analysis with Path analysis was conducted because we confirm the experience of discrimination was affected by life satisfaction and stress can affected life satisfaction as a moderator. The experience of discrimination significantly affects stress and stress significantly affects life satisfaction. However, the experience of discrimination was not directly related to life satisfaction. The more stress the study respondents experienced, the lower the life satisfaction they reported. The present finding suggests that the effects of discriminating experiences on the life satisfaction of North Korean refugees in South Korea were mediated by their own perceived stress.
Personality traits, future time perspective and adaptive behavior in adolescence.
Gomes Carvalho, Renato Gil; Novo, Rosa Ferreira
2015-04-24
Several studies provide evidence of the importance of future time perspective (FTP) for individual success. However, little research addresses the relationship between FTP and personality traits, particularly if FTP can mediate their influence on behavior. In this study we analyze the mediating of FTP in the influence of personality traits on the way adolescents live their life at school. Sample consisted in 351 students, aged from 14 to 18 years-old, at different schooling levels. Instruments were the Portuguese version of the MMPI-A, particularly the PSY-5 dimensions (Aggressiveness, Psychoticism, Disconstraint, Neuroticism, Introversion), a FTP questionnaire, and a survey on school life, involving several indicators of achievement, social integration, and overall satisfaction. With the exception of Neuroticism, the results show significant mediation effects (p < .001) of FTP on most relationships between PSY-5 dimensions and school life variables. Concerning Disconstraint, FTP mediated its influence on overall satisfaction (β = -.125) and school achievement (β = -.106). In the case of Introversion, significant mediation effects occurred for interpersonal difficulties (β = .099) and participation in extracurricular activities (β = -.085). FTP was also a mediator of Psychoticism influence in overall satisfaction (β = -.094), interpersonal difficulties (β = .057), and behavior problems (β = .037). Finally, FTP mediated the influence of Aggressiveness on overall satisfaction (β = -.061), interpersonal difficulties (β = .040), achievement (β = -.052), and behavior problems (β = .023). Results are discussed considering the importance of FTP in the impact of some personality structural characteristics in students' school adaptation.
Watt, Ashli D; Konnert, Candace A; Speirs, Calandra E C
2017-07-01
This study examined primary and secondary control as mediators in the relationship between body satisfaction and subjective well-being (SWB) and explored age differences in the mediation model. Data from 362 women, aged 40-91 years, assessed (i) the relationships between body satisfaction, age, primary and secondary control strategies (body-specific social comparison, acceptance, and positive reappraisal), and three indices of SWB (positive affect, negative affect, and life satisfaction), (ii) the mediation effects of primary and secondary control on the relationship between body satisfaction and SWB, and (iii) whether mediational relationships were moderated by age. Body satisfaction was unrelated to age but positively related to positive affect and life satisfaction and negatively related to negative affect. Body satisfaction was also related to primary and secondary control strategies. There were significant indirect (mediated) effects of body satisfaction on all outcome variables through acceptance and positive reappraisal. These mediators were significant at all age levels, but exerted their strongest influence among younger women. This study provides new information about the mechanisms that influence the relationship between body satisfaction and SWB among a broad age range of women who are experiencing physical changes that are inconsistent with Western beauty standards. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Building a Narrative Based Requirements Engineering Mediation Model
NASA Astrophysics Data System (ADS)
Ma, Nan; Hall, Tracy; Barker, Trevor
This paper presents a narrative-based Requirements Engineering (RE) mediation model to help RE practitioners to effectively identify, define, and resolve conflicts of interest, goals, and requirements. Within the SPI community, there is a common belief that social, human, and organizational issues significantly impact on the effectiveness of software process improvement in general and the requirements engineering process in particularl. Conflicts among different stakeholders are an important human and social issue that need more research attention in the SPI and RE community. By drawing on the conflict resolution literature and IS literature, we argue that conflict resolution in RE is a mediated process, in which a requirements engineer can act as a mediator among different stakeholders. To address socio-psychological aspects of conflict in RE and SPI, Winslade and Monk (2000)'s narrative mediation model is introduced, justified, and translated into the context of RE.
Probst, Thomas; Dinkel, Andreas; Schmid-Mühlbauer, Gabriele; Radziej, Katharina; Limburg, Karina; Pieh, Christoph; Lahmann, Claas
2017-02-01
Vertigo symptoms can lead to more or less vertigo-related handicap. This longitudinal study investigated whether depression, anxiety, and/or somatization mediate the relationship between vertigo symptoms and vertigo-related handicap. N=111 patients with vertigo/dizziness provided complete data on the following measures: Vertigo symptoms at baseline, depression at 6-month follow-up, anxiety at 6-month follow-up, somatization at 6-month follow-up, and vertigo handicap at 12-month follow-up. Mediation analyses with bootstrapping were performed to investigate the mediating role of anxiety, depression, and somatization in the relationship between vertigo symptoms and vertigo-related handicap. When the mediating role of anxiety, depression, and somatization was evaluated separately from each other in single mediation models, the effect vertigo symptoms at baseline exerted on vertigo-related handicap at 12-month follow-up was significantly mediated by depression at 6-month follow-up (p<0.05), by anxiety at 6-month follow-up (p<0.05), as well as by somatization at 6-month follow-up (p<0.05). When statistically controlling for the other mediators in a multiple mediator model, only depression at 6-month follow-up mediated the effect of vertigo symptoms at baseline on vertigo-related handicap at 12-month follow-up (p<0.05). Psychological distress is an important mechanism in the process how vertigo symptoms lead to vertigo-related handicap. Copyright © 2016 Elsevier Inc. All rights reserved.
Pinto, B M; Lynn, H; Marcus, B H; DePue, J; Goldstein, M G
2001-01-01
In theory-based interventions for behavior change, there is a need to examine the effects of interventions on the underlying theoretical constructs and the mediating role of such constructs. These two questions are addressed in the Physically Active for Life study, a randomized trial of physician-based exercise counseling for older adults. Three hundred fifty-five patients participated (intervention n = 181, control n = 174; mean age = 65.6 years). The underlying theories used were the Transtheoretical Model, Social Cognitive Theory and the constructs of decisional balance (benefits and barriers), self-efficacy, and behavioral and cognitive processes of change. Motivational readiness for physical activity and related constructs were assessed at baseline, 6 weeks, and 8 months. Linear or logistic mixed effects models were used to examine intervention effects on the constructs, and logistic mixed effects models were used for mediator analyses. At 6 weeks, the intervention had significant effects on decisional balance, self-efficacy, and behavioral processes, but these effects were not maintained at 8 months. At 6 weeks, only decisional balance and behavioral processes were identified as mediators of motivational readiness outcomes. Results suggest that interventions of greater intensity and duration may be needed for sustained changes in mediators and motivational readiness for physical activity among older adults.
Does positivity mediate the relation of extraversion and neuroticism with subjective happiness?
Lauriola, Marco; Iani, Luca
2015-01-01
Recent theories suggest an important role of neuroticism, extraversion, attitudes, and global positive orientations as predictors of subjective happiness. We examined whether positivity mediates the hypothesized relations in a community sample of 504 adults between the ages of 20 and 60 years old (females = 50%). A model with significant paths from neuroticism to subjective happiness, from extraversion and neuroticism to positivity, and from positivity to subjective happiness fitted the data (Satorra-Bentler scaled chi-square (38) = 105.91; Comparative Fit Index = .96; Non-Normed Fit Index = .95; Root Mean Square Error of Approximation = .060; 90% confidence interval = .046, .073). The percentage of subjective happiness variance accounted for by personality traits was only about 48%, whereas adding positivity as a mediating factor increased the explained amount of subjective happiness to 78%. The mediation model was invariant by age and gender. The results show that the effect of extraversion on happiness was fully mediated by positivity, whereas the effect of neuroticism was only partially mediated. Implications for happiness studies are also discussed.
Ko, Linda K; Turner-McGrievy, Gabrielle M; Campbell, Marci K
2014-04-01
Podcasting is an emerging technology, and previous interventions have shown promising results using theory-based podcast for weight loss among overweight and obese individuals. This study investigated whether constructs of social cognitive theory and information processing theories (IPTs) mediate the effect of a podcast intervention on weight loss among overweight individuals. Data are from Pounds off Digitally, a study testing the efficacy of two weight loss podcast interventions (control podcast and theory-based podcast). Path models were constructed (n = 66). The IPTs, elaboration likelihood model, information control theory, and cognitive load theory mediated the effect of a theory-based podcast on weight loss. The intervention was significantly associated with all IPTs. Information control theory and cognitive load theory were related to elaboration, and elaboration was associated with weight loss. Social cognitive theory constructs did not mediate weight loss. Future podcast interventions grounded in theory may be effective in promoting weight loss.
Zhao, Xiaojun; Shi, Changxiu
2018-01-01
This study analyzed the mediation effect of a suicidal attitude from regulatory emotional self-efficacy to core self-evaluation. A measurement study was conducted among 438 college students using the Regulatory Emotional Self-Efficacy Scale, the Core Self-Evaluation Scale, and the Suicide Attitude Questionnaire. Results from the plug-in process in SPSS and the bootstrap method showed that the attitude toward suicidal behavior and the attitude toward family members of an individual who has committed suicide played a double-mediation role, from perceived self-efficacy in managing happiness to core self-evaluation. The results also showed that the attitude toward a person who committed suicide or attempted suicide played a mediation effect from perceived self-efficacy in managing curiousness to core self-evaluation. This research has great significance for improving the understanding of college students' sense of happiness and prevention for self-evaluation.
Zhao, Xiaojun; Shi, Changxiu
2018-01-01
This study analyzed the mediation effect of a suicidal attitude from regulatory emotional self-efficacy to core self-evaluation. A measurement study was conducted among 438 college students using the Regulatory Emotional Self-Efficacy Scale, the Core Self-Evaluation Scale, and the Suicide Attitude Questionnaire. Results from the plug-in process in SPSS and the bootstrap method showed that the attitude toward suicidal behavior and the attitude toward family members of an individual who has committed suicide played a double-mediation role, from perceived self-efficacy in managing happiness to core self-evaluation. The results also showed that the attitude toward a person who committed suicide or attempted suicide played a mediation effect from perceived self-efficacy in managing curiousness to core self-evaluation. This research has great significance for improving the understanding of college students’ sense of happiness and prevention for self-evaluation. PMID:29740378
NASA Astrophysics Data System (ADS)
Liu, Rui; Yu, Xiwei; Su, Chang; Shi, Yijie; Zhao, Liang
2017-06-01
Artemisinin and its derivatives were considered to exert a broad spectrum of anti-cancer activities, and they induced significant anti-cancer effects in tumor cells. Artemisinin and its derivatives could be absorbed quickly, and they were widely distributed, selectively killing tumor cells. Since low concentrations of artesunate primarily depended on oncosis to induce cell death in tumor cells, its anti-tumor effects were undesirable and limited. To obtain better anti-tumor effects, in this study, we took advantage of a new nanotechnology to design novel artesunate-loaded bovine serum albumin nanoparticles to achieve the mitochondrial accumulation of artesunate and induce mitochondrial-mediated apoptosis. The results showed that when compared with free artesunate's reliance on oncotic death, artesunate-loaded bovine serum albumin nanoparticles showed higher cytotoxicity and their significant apoptotic effects were induced through the distribution of artesunate in the mitochondria. This finding indicated that artesunate-loaded bovine serum albumin nanoparticles damaged the mitochondrial integrity and activated mitochondrial-mediated cell apoptosis by upregulating apoptosis-related proteins and facilitating the rapid release of cytochrome C.
Fasanelli, Francesca; Zugna, Daniela; Giraudo, Maria Teresa; Krogh, Vittorio; Grioni, Sara; Panico, Salvatore; Mattiello, Amalia; Masala, Giovanna; Caini, Saverio; Tumino, Rosario; Frasca, Graziella; Sciannameo, Veronica; Ricceri, Fulvio; Sacerdote, Carlotta
2017-05-15
Adherence to the Mediterranean diet (MD) has a preventive effect on colorectal cancer (CRC). Several biological mechanisms have been hypothesized to explain this effect, but the involvement of clinical mediators has not been experimentally proven. We examined the role of abdominal adiposity (i.e., waist-to-hip ratio, WHR) as a potential mediator of the relationship between the MD and CRC in the Italian centres of the European Prospective Investigation into Cancer and Nutrition. We evaluated the effect of the Italian Mediterranean Index (IMI) on WHR and of WHR on CRC risk. We then estimated the natural indirect effect (NIE, mediated by WHR) and the pure direct effect (PDE, unmediated) of IMI on CRC risk using mediation analyses, considering age, sex, education, physical activity, smoking and EPIC centre as confounders. Increased IMI was associated with significantly decreased odds of high WHR (odds ratio [OR] for an IMI of 6-11 vs. 0-1: 0.88, 95% confidence interval [CI]: 0.81-0.97). There was a positive relationship between WHR and CRC (hazard ratio [HR] for high vs. low WHR: 1.34, 95%CI: 1.09-1.66). The total effect of IMI was protective on CRC risk and was mainly explained by the PDE (HR for an IMI of 6-11 vs. 0-1: 0.51, 95%CI: 0.31-0.83), whereas the NIE was 1.00 (95%CI: 0.94-1.10). In this Mediterranean cohort, the protective effect of the MD on the development of CRC was not mediated by abdominal adiposity. Since this is the first study to investigate the mediating effect of abdominal obesity, other studies are needed to replicate this result. © 2017 UICC.
Brechan, Inge; Kvalem, Ingela Lundin
2015-04-01
The purpose of this study was to investigate the hypothesis that the effect of body dissatisfaction on disordered eating behavior is mediated through self-esteem and depression. If the effect of body dissatisfaction on disordered eating can be explained by self-esteem and depression, treatment may benefit from focusing more on self-esteem and depression than body dissatisfaction. We also hypothesized body image importance to be associated with lower self-esteem, stronger symptoms of depression, and more disordered eating. The results showed that the effect of body dissatisfaction on disorder eating was completely mediated, whereas the effect of body image importance was partly mediated. Both self-esteem and depression were significant mediators. Body image importance and self-esteem had a direct effect on restrained eating and compensatory behavior. Depression had a direct effect on binge eating. This effect was significantly stronger among women. Depression also had a direct effect on restrained eating. This effect was positive among women, but negative among men. The results support emotion regulation and cognitive behavioral theories of eating disorders, indicating that self-esteem and depression are the most proximal factors, whereas the effect of body dissatisfaction is indirect. The results point out the importance of distinguishing between different symptoms of bulimia. Depression may cause binge eating, but compensatory behavior depends on self-esteem and body image importance. The results suggest that women may turn to both binge eating and restrained eating to escape awareness of negative emotions, whereas men focus on eating to a lesser extent than women. Existing treatment focuses on eating behavior first and mechanisms such as self-esteem and depression second. The results from this study suggest that an earlier focus on self-esteem and depression may be warranted in the treatment of disordered eating. Copyright © 2015 Elsevier Ltd. All rights reserved.
Kang, Sangwook; Jeon, Hyunsoo; Kwon, Sungho; Park, Seungha
2015-02-01
This study examined whether parental attachment mediates the relationship between parental social support and self-esteem in Korean middle and high school athletes. 591 sports athletes attending middle and high schools that specialize in sport volunteered. Parental social support and parental attachment had a significant positive effect on self-esteem; parental attachment had a greater effect on self-esteem. In the structural relationship, direct effects of parental social support on self-esteem were weak, but indirect effects through parental attachment were strong. Therefore, parental attachment complementally mediated the relationship between parental social support and self-esteem. Metric invariance was supported for groups categorized by sex, region, and school level, confirming that the model could be applied to various groups.
Sears, Sharon; Kraus, Sue
2009-06-01
This study examined cognitive distortions and coping styles as potential mediators for the effects of mindfulness meditation on anxiety, negative affect, positive affect, and hope in college students. Our pre- and postintervention design had four conditions: control, brief meditation focused on attention, brief meditation focused on loving kindness, and longer meditation combining both attentional and loving kindness aspects of mindfulness. Each group met weekly over the course of a semester. Longer combined meditation significantly reduced anxiety and negative affect and increased hope. Changes in cognitive distortions mediated intervention effects for anxiety, negative affect, and hope. Further research is needed to determine differential effects of types of meditation. Copyright 2009 Wiley Periodicals, Inc.
Patel, Sita Sharan; Ray, R S; Sharma, Arun; Mehta, Vineet; Katyal, Anju; Udayabanu, Malairaman
2018-04-27
The present study was aimed to investigate the effect of Urtica dioica Linn. (UD) extract against chronic diabetes mediated anxiogenic and depressive like behavior in mice. Streptozotocin (STZ) (50 mg/kg, i.p.) for 5 consecutive days was used to induce diabetes followed by treatment with UD leaves extract (50 mg/kg, p.o.) and rosiglitazone (ROSI) (5 mg/kg, p.o.) for 8 weeks. STZ induced chronic diabetes significantly induced anxiety and depressive like behavior in mice. Chronic diabetes significantly downregulated BDNF (p < 0.001), TrKB (p < 0.001), Cyclin D1 (p < 0.001), Bcl2 (p < 0.05) and autophagy7 (p < 0.001), while upregulated iNOS (p < 0.05) mRNA expression in the hippocampus as compared to control mice. In addition, chronic diabetes significantly increased the expression of TNF-α in CA1 (p < 0.001), CA2 (p < 0.01), CA3 (p < 0.001) and DG (p < 0.001) regions of hippocampus as compared to control mice. Chronic diabetes mediated neuronal damage in the CA2, CA3 and DG regions of hippocampus. Chronic administration of UD leaves extract significantly reversed diabetes mediated anxiogenic and depressive like behavior in mice. Further, UD treatment significantly upregulated BDNF (p < 0.01), TrKB (p < 0.001), Cyclin D1 (p < 0.001), Bcl2 (p < 0.01), autophagy5 (p < 0.01) and autophagy7 (p < 0.001), while downregulated iNOS (p < 0.05) mRNA expression in the hippocampus of diabetic mice. Concomitantly, UD administration significantly decreased the expression of TNF-α in hippocampal CA1 (p < 0.001), CA2 (p < 0.01), CA3 (p < 0.001) and DG (p < 0.001) regions of diabetic mice. Diabetes mediated neuronal damage and DNA fragmentation in the hippocampus was substantially attenuated following UD treatment. UD leaves extract might prove to be effective for diabetes mediated anxiety and depressive like behavior.
Appleyard, Karen; Berlin, Lisa J.; Rosanbalm, Katherine D.; Dodge, Kenneth A.
2013-01-01
In the interest of improving child maltreatment prevention science, this longitudinal, community based study of 499 mothers and their infants tested the hypothesis that mothers’ childhood history of maltreatment would predict maternal substance use problems, which in turn would predict offspring victimization. Mothers (35% White/non-Latina, 34% Black/non-Latina, 23% Latina, 7% other) were recruited and interviewed during pregnancy, and child protective services records were reviewed for the presence of the participants’ target infants between birth and age 26 months. Mediating pathways were examined through structural equation modeling and tested using the products of the coefficients approach. The mediated pathway from maternal history of sexual abuse to substance use problems to offspring victimization was significant (standardized mediated path [ab]=.07, 95% CI [.02, .14]; effect size=.26), as was the mediated pathway from maternal history of physical abuse to substance use problems to offspring victimization (standardized mediated path [ab]=.05, 95% CI [.01, .11]; effect size =.19). There was no significant mediated pathway from maternal history of neglect. Findings are discussed in terms of specific implications for child maltreatment prevention, including the importance of assessment and early intervention for maternal history of maltreatment and substance use problems, targeting women with maltreatment histories for substance use services, and integrating child welfare and parenting programs with substance use treatment. PMID:21240556
Gang membership and substance use: guilt as a gendered causal pathway
Coffman, Donna L.; Melde, Chris; Esbensen, Finn-Aage
2014-01-01
Objectives We examine whether anticipated guilt for substance use is a gendered mechanism underlying the noted enhancement effect of gang membership on illegal drug use. We also demonstrate a method for making stronger causal inferences when assessing mediation in the presence of moderation and time-varying confounding. Methods We estimate a series of inverse propensity weighted models to obtain unbiased estimates of mediation in the presence of confounding of the exposure (i.e., gang membership) and mediator (i.e., anticipated guilt) using three waves of data from a multi-site panel study of a law-related education program for youth (N=1,113). Results The onset of gang membership significantly decreased anticipated substance use guilt among both male and female respondents. This reduction was significantly associated with increased frequency of substance use only for female respondents, however, suggesting that gender moderates the mechanism through which gang membership influences substance use. Conclusions Criminologists are often concerned with identifying causal pathways for antisocial and/or delinquent behavior, but confounders of the exposure, mediator, and outcome often interfere with efforts to assess mediation. Many new approaches have been proposed for strengthening causal inference for mediation effects. After controlling for confounding using inverse propensity weighting, our results suggest that interventions aimed at reducing substance use by current and former female gang members should focus on the normative aspects of these behaviors. PMID:26190954
Appleyard, Karen; Berlin, Lisa J; Rosanbalm, Katherine D; Dodge, Kenneth A
2011-06-01
In the interest of improving child maltreatment prevention science, this longitudinal, community based study of 499 mothers and their infants tested the hypothesis that mothers' childhood history of maltreatment would predict maternal substance use problems, which in turn would predict offspring victimization. Mothers (35% White/non-Latina, 34% Black/non-Latina, 23% Latina, 7% other) were recruited and interviewed during pregnancy, and child protective services records were reviewed for the presence of the participants' target infants between birth and age 26 months. Mediating pathways were examined through structural equation modeling and tested using the products of the coefficients approach. The mediated pathway from maternal history of sexual abuse to substance use problems to offspring victimization was significant (standardized mediated path [ab] = .07, 95% CI [.02, .14]; effect size = .26), as was the mediated pathway from maternal history of physical abuse to substance use problems to offspring victimization (standardized mediated path [ab] = .05, 95% CI [.01, .11]; effect size = .19). There was no significant mediated pathway from maternal history of neglect. Findings are discussed in terms of specific implications for child maltreatment prevention, including the importance of assessment and early intervention for maternal history of maltreatment and substance use problems, targeting women with maltreatment histories for substance use services, and integrating child welfare and parenting programs with substance use treatment.
Benzo, Roberto P; Abascal-Bolado, Beatriz; Dulohery, Megan M
2016-04-01
This study aimed to increase our understanding of general self-management (SM) abilities in COPD by determining if SM can predict disease specific quality of life (QoL), by investigating whether specific SM domains are significant in COPD and by exploring the mediating effect of the positive/negative affect in the association between SM and QoL. Cross-sectional study based on 292 patients with COPD. Measures included demographics, lung function, gait speed, health care utilization, positive/negative affect, SM abilities, breathlessness and disease specific QoL. We performed, correlation, multiple regression models and mediation analysis (positive/negative affect being mediator between SM and QoL association). After controlling for breathlessness, living alone, marital status, hospitalization history, age and lung function, SM related to QoL (p<0.0001). Investment in behaviors (hobbies and social relationships) and self-efficacy are SM domains independently related to QoL in COPD. Positivity measured by the positive/negative affect ratio completely mediates the relationship of SM with QoL. SM is independently associated with disease specific QoL in COPD after adjustment significant covariates but positive/negative affect ratio completely mediates the relationship of SM with QoL. Measuring positive/negative affect and addressing investment behavior and self-efficacy are important in implementing COPD-SM programs. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.
Gang membership and substance use: guilt as a gendered causal pathway.
Coffman, Donna L; Melde, Chris; Esbensen, Finn-Aage
2015-03-01
We examine whether anticipated guilt for substance use is a gendered mechanism underlying the noted enhancement effect of gang membership on illegal drug use. We also demonstrate a method for making stronger causal inferences when assessing mediation in the presence of moderation and time-varying confounding. We estimate a series of inverse propensity weighted models to obtain unbiased estimates of mediation in the presence of confounding of the exposure (i.e., gang membership) and mediator (i.e., anticipated guilt) using three waves of data from a multi-site panel study of a law-related education program for youth ( N =1,113). The onset of gang membership significantly decreased anticipated substance use guilt among both male and female respondents. This reduction was significantly associated with increased frequency of substance use only for female respondents, however, suggesting that gender moderates the mechanism through which gang membership influences substance use. Criminologists are often concerned with identifying causal pathways for antisocial and/or delinquent behavior, but confounders of the exposure, mediator, and outcome often interfere with efforts to assess mediation. Many new approaches have been proposed for strengthening causal inference for mediation effects. After controlling for confounding using inverse propensity weighting, our results suggest that interventions aimed at reducing substance use by current and former female gang members should focus on the normative aspects of these behaviors.
Foshee, Vangie A.; Ennett, Susan T.
2012-01-01
Background To understand how neighborhoods influence the development of youth violence, we investigated intrapersonal mediators of the relationship between neighborhood disadvantage and youth violence trajectories between ages 11 and 18. The hypothesized mediators included indicators of social bonding (belief in conventional values, involvement in school activities, religious engagement, and commitment to traditional goals) and psychological distress. Methods The sample (N=5,118) was 50% female and 52% Caucasian. Data from a 5-wave panel study spanning ages 11 to 18 were analyzed using sex-stratified multilevel growth curves. Results Neighborhood disadvantage was associated with higher levels of violence perpetrated by girls, lower belief in conventional values for both girls and boys, less commitment to traditional goals by girls, and higher levels of psychological distress reported by girls. Sobel tests identified three significant mediators of the effects of neighborhood disadvantage on girls’ violence trajectories: belief in conventional values, commitment to traditional goals and psychological distress. The only significant mediator of the relationship between neighborhood disadvantage and boys’ violence trajectories was belief in conventional values. The effects of neighborhood disadvantage on violence trajectories were not fully mediated; in fact, results suggested suppression effects, or inconsistent mediation, may exist. Conclusions The results emphasize the importance of both contextual and intrapersonal attributes in understanding the development of violence among school-age youth. Early school-based and community-level prevention initiatives that promote social bonding and address mental health needs may help reduce the impact of youth violence, particularly for girls. PMID:22070508
Wang, Lin-Lin; Yu, Qun-Li; Han, Ling; Ma, Xiu-Li; Song, Ren-De; Zhao, Suo-Nan; Zhang, Wen-Hua
2018-04-01
This study investigated the effect of reactive oxygen species-mediated oxidative stress on activation of mitochondrial apoptosis and tenderness of yak meat during postmortem ageing. Oxidative stress degree, Ca 2+ levels, membrane permeability transition pore opening, mitochondrial membrane potential, apoptotic factors and the shear force were examined. Results showed that the ROS generated by H 2 O 2 significantly increased mitochondrial oxidative stress by decreasing the activities of superoxide dismutase, catalase and glutathione peroxidase, and increasing lipid peroxidation. Furthermore, oxidative stress enhanced Ca 2+ production and cytochrome c release, changed the levels of Bcl-2 family proteins and activated caspase-9 and -3 activities. Ultimately, oxidative stress increased the apoptosis rate and tenderness of yak meat. These observations confirmed that ROS-mediated oxidative stress participates in the activation of the apoptotic cascade reaction involving Ca 2+ and Bcl-2 family proteins. The results further suggested that ROS-mediated oxidative stress plays a significant role in meat tenderization through the mitochondrial apoptotic pathway. Copyright © 2017. Published by Elsevier Ltd.
Faghri, Pouran D; Simon, Julia; Huedo-Medina, Tania; Gorin, Amy
2017-05-01
To evaluate if self-efficacy (SE) and financial incentives (FI) mediate the effect of health behavior on weight loss in a group of overweight and obese nursing-home employees participating in a 16-week weight-loss intervention with 12-week follow-up. Ninety nine overweight/obese (body mass index [BMI] > 25) employees from four nursing-homes participated, with a mean age of 46.98 years and BMI of 35.33. Nursing-homes were randomized to receiving an incentive-based intervention (n = 51) and no incentive (n = 48). Participants' health behaviors and eating and exercise self-efficacy (Ex-SE) were assessed at week 1, 16, and 28 using a self-reported questionnaire. Mediation and moderated mediation analysis assessed relationships among these variables. Eating self-efficacy (Eat-SE) and Ex-SE were significant mediators between health behaviors and weight loss (P < 0.05). Incentives significantly moderated the effects of self-efficacy (P = 0.00) on weight loss. Self-efficacy and FI may affect weight loss and play a role in weight-loss interventions.
Scherr, Kyle C; Madon, Stephanie; Guyll, Max; Willard, Jennifer; Spoth, Richard
2011-05-01
This research examined whether self-verification acts as a general mediational process of self-fulfilling prophecies. The authors tested this hypothesis by examining whether self-verification processes mediated self-fulfilling prophecy effects within a different context and with a different belief and a different outcome than has been used in prior research. Results of longitudinal data obtained from mothers and their adolescents (N=332) indicated that mothers' beliefs about their adolescents' educational outcomes had a significant indirect effect on adolescents' academic attainment through adolescents' educational aspirations. This effect, observed over a 6-year span, provided evidence that mothers' self-fulfilling effects occurred, in part, because mothers' false beliefs influenced their adolescents' own educational aspirations, which adolescents then self-verified through their educational attainment. The theoretical and applied implications of these findings are discussed.
Scherr, Kyle C.; Madon, Stephanie; Guyll, Max; Willard, Jennifer; Spoth, Richard
2013-01-01
This research examined whether self-verification acts as a general mediational process of self-fulfilling prophecies. The authors tested this hypothesis by examining whether self-verification processes mediated self-fulfilling prophecy effects within a different context and with a different belief and a different outcome than has been used in prior research. Results of longitudinal data obtained from mothers and their adolescents (N = 332) indicated that mothers’ beliefs about their adolescents’ educational outcomes had a significant indirect effect on adolescents’ academic attainment through adolescents’ educational aspirations. This effect, observed over a six year span, provided evidence that mothers’ self-fulfilling effects occurred, in part, because mothers’ false beliefs influenced their adolescents’ own educational aspirations which adolescents then self-verified through their educational attainment. The theoretical and applied implications of these findings are discussed. PMID:21357755
2017-01-01
Background Web-based medical service (WBMS), a cooperative relationship between medical service and Internet technology, has been called one of the most innovative services of the 21st century. However, its business promotion and implementation in the medical industry have neither been expected nor executed. Few studies have explored this phenomenon from the viewpoint of inexperienced patients. Objective The primary goal of this study was to explore whether technology attractiveness, medical creditability, and diversified medical information sources could increase users’ behavior intention. Methods This study explored the effectiveness of web-based medical service by using three situations to manipulate sources of medical information. A total of 150 questionnaires were collected from people who had never used WBMS before. Hierarchical regression was used to examine the mediation and moderated-mediation effects. Results Perceived ease of use (P=.002) and perceived usefulness (P=.001) significantly enhance behavior intentions. Medical credibility is a mediator (P=.03), but the relationship does not significantly differ under diverse manipulative information channels (P=.39). Conclusions Medical credibility could explain the extra variation between technology attractiveness and behavior intention, but not significant under different moderating effect of medical information sources. PMID:28768608
Examining mediators of child sexual abuse and sexually transmitted infections.
Sutherland, Melissa A
2011-01-01
Interpersonal violence has increasingly been identified as a risk factor for sexually transmitted infections. Understanding the pathways between violence and sexually transmitted infections is essential to designing effective interventions. The aim of this study was to examine dissociative symptoms, alcohol use, and intimate partner physical violence and sexual coercion as mediators of child sexual abuse and lifetime sexually transmitted infection diagnosis among a sample of women. A convenience sample of 202 women was recruited from healthcare settings, with 189 complete cases for analysis. A multiple mediation model tested the proposed mediators of child sexual abuse and lifetime sexually transmitted infection diagnosis. Bootstrapping, a resampling method, was used to test for mediation. Key variables included child sexual abuse, dissociative symptoms, alcohol use, and intimate partner violence. Child sexual abuse was reported by 46% of the study participants (n = 93). Child sexual abuse was found to have an indirect effect on lifetime sexually transmitted infection diagnosis, with the effect occurring through dissociative symptoms (95% confidence interval = 0.0033-0.4714) and sexual coercion (95% confidence interval = 0.0359-0.7694). Alcohol use and physical violence were not found to be significant mediators. This study suggests that dissociation and intimate partner sexual coercion are important mediators of child sexual abuse and sexually transmitted infection diagnosis. Therefore, interventions that consider the roles of dissociative symptoms and interpersonal violence may be effective in preventing sexually transmitted infections among women.
Morinelli, Thomas A; Walker, Linda P; Velez, Juan Carlos Q; Ullian, Michael E
2015-02-05
The major effects of Angiotensin II (AngII) in vascular tissue are mediated by AngII AT1A receptor activation. Certain effects initiated by AT1A receptor activation require receptor internalization. In rat aortic vascular smooth muscle cells (RASMC), AngII stimulates cyclooxygenase 2 protein expression. We have previously shown this is mediated by β-arrestin-dependent receptor internalization and NF-κB activation. In this study, a specific inhibitor of clathrin-mediated endocytosis (CME), pitstop-2, was used to test the hypothesis that clathrin-dependent internalization of activated AT1A receptor mediates NF-κB activation and subsequent cyclooxygenase 2 expression. Radioligand binding assays, real time qt-PCR and immunoblotting were used to document the effects of pitstop-2 on AngII binding and signaling in RASMC. Laser scanning confocal microscopy (LSCM) was used to image pitstop-2׳s effects on AT1 receptor/GFP internalization in HEK-293 cells and p65 NF-κB nuclear localization in RASMC. Pitstop-2 significantly inhibited internalization of AT1A receptor (44.7% ± 3.1% Control vs. 13.2% ± 8.3% Pitstop-2; n=3) as determined by radioligand binding studies in RASMC. Studies utilizing AT1A receptor/GFP expressed in HEK 293 cells and LSCM confirmed these findings. Pitstop-2 significantly inhibited AngII-induced p65 NF-κB phosphorylation and nuclear localization, COX-2 message and protein expression in RASMC without altering activation of p42/44 ERK or TNFα signaling. Pitstop-2, a specific inhibitor of clathrin-mediated endocytosis, confirms that internalization of activated AT1A receptor mediates AngII activation of cyclooxygenase 2 expression in RASMC. These data provide support for additional intracellular signaling pathways activated through β-arrestin mediated internalization of G protein-coupled receptors, such as AT1A receptors. Copyright © 2014 Elsevier B.V. All rights reserved.
Evaluation of a safety training program in three food service companies.
Sinclair, Raymond C; Smith, Randall; Colligan, Michael; Prince, Mary; Nguyen, Trang; Stayner, Leslie
2003-01-01
Outcome measures for safety training effectiveness research often do not include measures such as occupational injury experience. Effectiveness mediators also receive sparse attention. A new safety training curriculum was delivered to workers in a stratified random sample of food service facilities across three companies. A similar group of facilities received usual training. We collected post-test measures of demographic variables, safety knowledge, perceptions of transfer of training climate, and workers' compensation claim data for one year after the initial training activities. Knowledge test scores were apparently higher in the new-training units than in the usual-training units. Some demographic variables were inconsistently associated with these differences. Evidence for reduction of the injury rate associated with the new training was observed from two companies but only approached significance for one company. A second company revealed a similar but non-significant trend. Knowledge scores were not significantly associated with lower injury rates. We found evidence that safety training increases knowledge and reduces injuries. We found almost no evidence of effects of training effectiveness mediators, including no relationship between safety knowledge and injury experience. Methodological issues related to conducting a large study may have influenced these results. Although safety training leads to greater knowledge and, in some cases, reduced occupational injuries, the influence of mediating variables remains to be fully explained.
Relationship between self-efficacy and physical activity among patients with type 2 diabetes.
Dutton, Gareth R; Tan, Fei; Provost, Bridgette C; Sorenson, Jamie L; Allen, Brandon; Smith, Dawn
2009-06-01
While previous studies indicate a significant relationship between self-efficacy and physical activity, less research has focused on this relationship among patients with type 2 diabetes. The purpose of this investigation was to examine whether self-efficacy mediated the relationship between participation in a 1-month, print-based physical activity intervention and improvements in activity levels. Participants (N = 85; mean age = 57; 73% Caucasian; 69% female) were recruited from a community diabetes center. The intervention was individually-tailored based on theoretical constructs, including self-efficacy. After controlling for age, baseline activity, and baseline self-efficacy, the tailored intervention was associated with significant improvements in physical activity, 95% CI [23.01, 271.68] as well as self-efficacy, CI [0.02, 3.48]. There was an indirect effect of treatment on physical activity through self-efficacy, CI [0.77, 73.11], and the direct effect of treatment on physical activity was no longer significant, CI [-7.33, 253.40], after the influences of self-efficacy change were accounted for in the model. Results supported a mediation effect, such that the treatment effect on physical activity was completely mediated by changes in self-efficacy. Although replication is needed, results support the theoretical rationale for targeting self-efficacy to promote physical activity among patients with type 2 diabetes.
Cohen, Lisa J; Ardalan, Firouz; Tanis, Thachell; Halmi, Winter; Galynker, Igor; Von Wyl, Agnes; Hengartner, Michael P
2017-02-01
This paper tests the hypothesis that the association between childhood maltreatment and adult personality dysfunction is at least partially attributable to insecure attachment, that is that attachment style mediates the relationship between childhood maltreatment and adult personality dysfunction. Associations between childhood trauma, as measured by the Childhood Trauma Questionnaire (CTQ), anxious and avoidant attachment in romantic relationships, as measured by the Experiences in Close Relationships-Revised (ECR-R), and five personality domains, as measured by the Severity Indices of Personality Problems (SIPP-118), were examined in a sample of 72 psychiatric inpatients. The SIPP-118 domains included relational capacities, identity integration, self-control, responsibility, and social concordance. The direct effect of childhood trauma on all SIPP-118 domains was not significant after controlling for the indirect effect of attachment. In regression modeling, a significant indirect effect of childhood trauma via adult attachment style was found for SIPP-118 relational capacities, identity integration, self-control, and social concordance. Specifically, anxious attachment was a significant mediator of the effect of childhood trauma on self-control, identity integration, and relational domains. These results suggest that childhood trauma impacts a broad range of personality domains and does so in large part through the pathway of anxious romantic attachment style.
School Engagement Mediates Long Term Prevention Effects for Mexican American Adolescents
Gonzales, Nancy A.; Wong, Jessie J.; Toomey, Russell B.; Millsap, Roger; Dumka, Larry E.; Mauricio, Anne M.
2014-01-01
This five year follow-up of a randomized clinical trial evaluated the efficacy of a family-focused intervention delivered in middle school to increase school engagement following transition to high school (2 years posttest), and also evaluated mediated effects through school engagement on multiple problem outcomes in late adolescence (5 years posttest). The study sample included 516 Mexican American adolescents who participated in a randomized trial of the Bridges to High School Program (Bridges/ Puentes). Path models representing the direct and indirect effects of the program on four outcome variables were evaluated using school engagement measured in the 9th grade as a mediator. The program significantly increased school engagement, with school engagement mediating intervention effects on internalizing symptoms, adolescent substance use, and school dropout in late adolescence when most adolescents were in the 12th grade. Effects on substance use were stronger for youth at higher risk based on pretest report of substance use initiation. There were no direct or indirect intervention effects on externalizing symptoms. Findings support that school engagement is an important prevention target for Mexican American adolescents. PMID:24398825
2013-01-01
This study examined how parenting and family characteristics targeted in a selective prevention program mediated effects on key youth proximal outcomes related to violence perpetration. The selective intervention was evaluated within the context of a multi-site trial involving random assignment of 37 schools to four conditions: a universal intervention composed of a student social-cognitive curriculum and teacher training, a selective family-focused intervention with a subset of high-risk students, a condition combining these two interventions, and a no-intervention control condition. Two cohorts of sixth-grade students (total N=1,062) exhibiting high levels of aggression and social influence were the sample for this study. Analyses of pre-post change compared to controls using intent-to-treat analyses found no significant effects. However, estimates incorporating participation of those assigned to the intervention and predicted participation among those not assigned revealed significant positive effects on student aggression, use of aggressive strategies for conflict management, and parental estimation of student’s valuing of achievement. Findings also indicated intervention effects on two targeted family processes: discipline practices and family cohesion. Mediation analyses found evidence that change in these processes mediated effects on some outcomes, notably aggressive behavior and valuing of school achievement. Results support the notion that changing parenting practices and the quality of family relationships can prevent the escalation in aggression and maintain positive school engagement for high-risk youth. PMID:21932067
Tomczyk, Samuel; Isensee, Barbara; Hanewinkel, Reiner
2015-12-01
Ample studies discuss the enhancing effects of peer drinking on student alcohol use. In addition, there is vast research on school climate impact on student alcohol use. Though these two areas are intertwined for most young adolescents, it is heretofore not completely clear, in what way these characteristics functionally interact and affect drinking behavior. In a longitudinal study, we analyzed a sample of 2490 German adolescents (Mage=13.32, SD=0.57, range=8-13) from 5th (fall 2010) to 8th (fall 2013) grade. We discerned mediating (class climate) and moderating (school organization variables) functions of school on the association between peer and adolescent alcohol use, and finally combined them in direct effect moderated mediation models for a variety of outcomes (lifetime alcohol use, frequency and amount of drinking, binge drinking), adjusting for possible confounders. Class climate mediated a small significant part of the association between peer and adolescent alcohol use (1.8-2.4%), with the exception of lifetime drinking. Student-teacher ratio and percentage of at-risk students significantly moderated the peer-adolescent association, with the latter having an enhancing and the first having a buffering effect. School life serves as an important context of adolescent development and as such, seems to have direct and indirect effects on behavior and health. Future research should pay attention to differentiating effects of school climate and include both forms of operationalization when analyzing school effects on student behavior. Copyright © 2015 Elsevier Ltd. All rights reserved.
Potential Mediators in Parenting and Family Intervention: Quality of Mediation Analyses
Patel, Chandni C.; Fairchild, Amanda J.; Prinz, Ronald J.
2017-01-01
Parenting and family interventions have repeatedly shown effectiveness in preventing and treating a range of youth outcomes. Accordingly, investigators in this area have conducted a number of studies using statistical mediation to examine some of the potential mechanisms of action by which these interventions work. This review examined from a methodological perspective in what ways and how well the family-based intervention studies tested statistical mediation. A systematic search identified 73 published outcome studies that tested mediation for family-based interventions across a wide range of child and adolescent outcomes (i.e., externalizing, internalizing, and substance-abuse problems; high-risk sexual activity; and academic achievement), for putative mediators pertaining to positive and negative parenting, family functioning, youth beliefs and coping skills, and peer relationships. Taken as a whole, the studies used designs that adequately addressed temporal precedence. The majority of studies used the product of coefficients approach to mediation, which is preferred, and less limiting than the causal steps approach. Statistical significance testing did not always make use of the most recently developed approaches, which would better accommodate small sample sizes and more complex functions. Specific recommendations are offered for future mediation studies in this area with respect to full longitudinal design, mediation approach, significance testing method, documentation and reporting of statistics, testing of multiple mediators, and control for Type I error. PMID:28028654
Ariyabuddhiphongs, Vanchai; Promsakha Na Sakolnakorn, Chomnad
2014-09-01
Our study hypothesizes that Thai amateur golfers gamble on their game because of peer pressure and their golf self-efficacy. To support our hypothesis, we conducted a study to examine the mediating effect of golf self-efficacy on the peer pressure-golf gambling relationship among 387 amateur golfers in Thailand. Peer pressure was operationally defined as fellow players' influence on the individual golfer to gamble; golf self-efficacy as the judgment of the golfer's skills to play golf; and golf gambling as the frequency and amounts of gambling. Regression analysis with bootstrapping was used to test the mediation effect of golf self-efficacy on the peer pressure-golf gambling relationship. The results support our hypothesis; peer pressure predicted golf gambling, and the indirect effect of peer pressure to golf gambling through the mediation of golf self-efficacy was significant. The results support the influence of peer pressure on gambling, and the social cognitive theory reciprocal relationship model.
Mereish, Ethan H; O'Cleirigh, Conall; Bradford, Judith B
2014-01-01
Research has documented significant relationships between sexual and gender minority stress and higher rates of suicidality (i.e. suicidal ideation and attempts) and substance use problems. We examined the potential mediating role of substance use problems on the relationship between sexual and gender minority stress (i.e. victimization based on lesbian, gay, bisexual, or transgender identity [LGBT]) and suicidality. A nonprobability sample of LGBT patients from a community health center (N = 1457) ranged in age from 19-70 years. Participants reported history of lifetime suicidal ideation and attempts, substance use problems, as well as experiences of LGBT-based verbal and physical attacks. Substance use problems were a significant partial mediator between LGBT-based victimization and suicidal ideation and between LGBT-based victimization and suicide attempts for sexual and gender minorities. Nuanced gender differences revealed that substance use problems did not significantly mediate the relationship between victimization and suicide attempts for sexual minority men. Substance use problems may be one insidious pathway that partially mediates the risk effects of sexual and gender minority stress on suicidality. Substances might be a temporary and deleterious coping resource in response to LGBT-based victimization, which have serious effects on suicidal ideation and behaviors.
Mereish, Ethan H.; O'Cleirigh, C; Bradford, Judith B.
2013-01-01
Research has documented significant relationships between sexual and gender minority stress and higher rates of suicidality (i.e., suicidal ideation and attempts) and substance use problems. We examined the potential mediating role of substance use problems on the relationship between sexual and gender minority stress (i.e., victimization based on lesbian, gay, bisexual, or transgender identity; LGBT) and suicidality. A non-probability sample of LGBT patients from a community health center (N = 1457) ranged in age 19 to 70 years. Participants reported history of lifetime suicidal ideation and attempts, and substance use problems, as well as experiences of LGBT-based verbal and physical attacks. Substance use problems were a significant partial mediator between LGBT-based victimization and suicidal ideation and between LGBT-based victimization and suicide attempts for sexual and gender minorities. Nuanced gender differences revealed that substance use problems did not significantly mediate the relationship between victimization and suicide attempts for sexual minority men. Substance use problems may be one insidious pathway that partially mediates the risk effects of sexual and gender minority stress on suicidality. Substances might be a temporary and deleterious coping resource in response to LGBT-based victimization, which have serious effects on suicidal ideation and behaviors. PMID:23535038
Organizational strategies mediate nonverbal memory impairment in obsessive-compulsive disorder.
Savage, C R; Baer, L; Keuthen, N J; Brown, H D; Rauch, S L; Jenike, M A
1999-04-01
Previous neuropsychological studies of obsessive-compulsive disorder (OCD) have indicated impaired executive functioning and nonverbal memory. The extent to which impaired executive functioning impacts nonverbal memory has not been established. The current study investigated the mediating effects of organizational strategies used when copying a figure on subsequent nonverbal memory for that figure. We examined neuropsychological performance in 20 unmedicated subjects with OCD and 20 matched normal control subjects. Subjects were administered the Rey-Osterrieth Complex Figure Test (RCFT) and neuropsychological tests assessing various aspects of executive function. OCD subjects differed significantly from healthy control subjects in the organizational strategies used to copy the RCFT figure, and they recalled significantly less information on both immediate and delayed testing. Multiple regression analyses indicated that group differences in immediate percent recall were significantly mediated by copy organizational strategies. Further exploratory analyses indicated that organizational problems in OCD may be related to difficulties shifting mental and/or spatial set. Immediate nonverbal memory problems in OCD subjects were mediated by impaired organizational strategies used during the initial copy of the RCFT figure. Thus, the primary deficit was one affecting executive function, which then had a secondary effect on immediate memory. These findings are consistent with current theories proposing frontal-striatal system dysfunction in OCD.
Kan, Chiemi; Kawakami, Norito; Karasawa, Mayumi; Love, Gayle Dienberg; Coe, Christopher L; Miyamoto, Yuri; Ryff, Carol D; Kitayama, Shinobu; Curhan, Katherine B; Markus, Hazel Rose
2014-02-01
Recently, researchers have proposed that psychological resources might be key concept in explaining the association between social class and health. However, empirical examinations of the extent to which psychological resources to social class in health are still few. This study investigated mediating effects of selected psychological resources (sense of control, self-esteem, optimism, and neuroticism) on the association of social class [education and subjective social status (SSS)] with current health status (self-rated health and the number of chronic conditions). This sample consisted of 1,805 Americans (818 males and 987 females) from the Midlife in the United States (MIDUS) survey, 2004-2006 and 1,027 Japanese (505 males and 522 females) from the Midlife in Japan (MIDJA) survey in Tokyo, Japan, 2008-2010. Information on social class, psychological resources, and health status was obtained using telephone interviews or written questionnaires. A mediation analysis was conducted separately for males and females in Japan and the USA. Neuroticism significantly mediated the association of education and SSS with self-rated health and chronic conditions among males and females in both countries, with one exception (not for chronic conditions among Japanese females). Sense of control significantly mediated the association of education and SSS with self-rated health among males and females in both countries. As hypothesized, self-esteem significantly mediated almost all of the associations of education and SSS with self-rated health and chronic conditions among men and women in the USA, but very few such associations in Japan. Optimism significantly mediated most associations of social class and health status in both countries, but only among females. Overall, the findings underscore important culture- and gender specificity in the ways in which psychosocial resources mediate the links between social class and health.
Breastfeeding and Childhood IQ: The Mediating Role of Gray Matter Volume.
Luby, Joan L; Belden, Andy C; Whalen, Diana; Harms, Michael P; Barch, Deanna M
2016-05-01
A substantial body of literature has established the positive effect of breastfeeding on child developmental outcomes. There is increasing consensus that breastfed children have higher IQs after accounting for key variables, including maternal education, IQ, and socioeconomic status. Cross-sectional investigations of the effects of breastfeeding on structural brain development suggest that breastfed infants have larger whole brain, cortical, and white matter volumes. To date, few studies have related these measures of brain structure to IQ in breastfed versus nonbreastfed children in a longitudinal sample. Data were derived from the Preschool Depression Study (PDS), a prospective longitudinal study in which children and caregivers were assessed annually for 8 waves over 11 years. A subset completed neuroimaging between the ages of 9.5 and 14.11 years. A total of 148 individuals had breastfeeding data at baseline and complete data on all variables of interest, including IQ and structural neuroimaging. General linear models and process mediation models were used. Breastfed children had significantly higher IQ scores and larger whole brain, total gray matter, total cortical gray matter, and subcortical gray matter volumes compared with the nonbreastfed group in models that covaried for key variables. Subcortical gray matter volume significantly mediated the association between breastfeeding and children's IQ scores. The study findings suggest that the effects of breastfeeding on child IQ are mediated through subcortical gray volume. This effect and putative mechanism is of public health significance and further supports the importance of breastfeeding in mental health promotion. Copyright © 2016 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.
Breastfeeding and Childhood IQ: The Mediating Role of Gray Matter Volume
Luby, Joan L.; Belden, Andy C.; Whalen, Diana; Harms, Michael P.; Barch, Deanna M.
2016-01-01
Objective A substantial body of literature has established the positive effect of breastfeeding on child developmental outcomes. There is increasing consensus that breastfed children have higher IQs after accounting for key variables, including maternal education, IQ, and socioeconomic status. Cross-sectional investigations of the effects of breastfeeding on structural brain development suggest that breastfed infants have larger whole brain, cortical, and white matter volumes. To date, few studies have related these measures of brain structure to IQ in breastfed versus nonbreastfed children in a longitudinal sample. Method Data were derived from the Preschool Depression Study (PDS), a prospective longitudinal study in which children and caregivers were assessed annually for 8 waves over 11 years. A subset completed neuroimaging between the ages of 9.5 and 14.11 years. A total of 148 individuals had breastfeeding data at baseline and complete data on all variables of interest, including IQ and structural neuroimaging. General linear models and process mediation models were used. Results Breastfed children had significantly higher IQ scores and larger whole brain, total gray matter, total cortical gray matter, and subcortical gray matter volumes compared with the nonbreastfed group in models that covaried for key variables. Subcortical gray matter volume significantly mediated the association between breast-feeding and children's IQ scores. Conclusion The study findings suggest that the effects of breastfeeding on child IQ are mediated through subcortical gray volume. This effect and putative mechanism is of public health significance and further supports the importance of breastfeeding in mental health promotion. PMID:27126850
Park, Ji Hye; Choi, Sung Hyun; Kim, Hyungtae; Ji, Seung Taek; Jang, Woong Bi; Kim, Jae Ho; Baek, Sang Hong; Kwon, Sang Mo
2016-10-09
Doxorubicin (DOXO) is widely used to treat solid tumors. However, its clinical use is limited by side effects including serious cardiotoxicity due to cardiomyocyte damage. Resident cardiac progenitor cells (hCPCs) act as key regulators of homeostasis in myocardial cells. However, little is known about the function of hCPCs in DOXO-induced cardiotoxicity. In this study, we found that DOXO-mediated hCPC toxicity is closely related to calcium-related autophagy signaling and was significantly attenuated by blocking mTOR signaling in human hCPCs. DOXO induced hCPC apoptosis with reduction of SMP30 (regucalcin) and autophagosome marker LC3, as well as remarkable induction of the autophagy-related markers, Beclin-1, APG7, and P62/SQSTM1 and induction of calcium-related molecules, CaM (Calmodulin) and CaMKII (Calmodulin kinase II). The results of an LC3 puncta assay further indicated that DOXO reduced autophagosome formation via accumulation of cytosolic Ca 2+ . Additionally, DOXO significantly induced mTOR expression in hCPCs, and inhibition of mTOR signaling by rapamycin, a specific inhibitor, rescued DOXO-mediated autophagosome depletion in hCPCs with significant reduction of DOXO-mediated cytosolic Ca 2+ accumulation in hCPCs, and restored SMP30 and mTOR expression. Thus, DOXO-mediated hCPC toxicity is linked to Ca 2+ -related autophagy signaling, and inhibition of mTOR signaling may provide a cardio-protective effect against DOXO-mediated hCPC toxicity.
Park, Ji Hye; Choi, Sung Hyun; Kim, Hyungtae; Ji, Seung Taek; Jang, Woong Bi; Kim, Jae Ho; Baek, Sang Hong; Kwon, Sang Mo
2016-01-01
Doxorubicin (DOXO) is widely used to treat solid tumors. However, its clinical use is limited by side effects including serious cardiotoxicity due to cardiomyocyte damage. Resident cardiac progenitor cells (hCPCs) act as key regulators of homeostasis in myocardial cells. However, little is known about the function of hCPCs in DOXO-induced cardiotoxicity. In this study, we found that DOXO-mediated hCPC toxicity is closely related to calcium-related autophagy signaling and was significantly attenuated by blocking mTOR signaling in human hCPCs. DOXO induced hCPC apoptosis with reduction of SMP30 (regucalcin) and autophagosome marker LC3, as well as remarkable induction of the autophagy-related markers, Beclin-1, APG7, and P62/SQSTM1 and induction of calcium-related molecules, CaM (Calmodulin) and CaMKII (Calmodulin kinase II). The results of an LC3 puncta assay further indicated that DOXO reduced autophagosome formation via accumulation of cytosolic Ca2+. Additionally, DOXO significantly induced mTOR expression in hCPCs, and inhibition of mTOR signaling by rapamycin, a specific inhibitor, rescued DOXO-mediated autophagosome depletion in hCPCs with significant reduction of DOXO-mediated cytosolic Ca2+ accumulation in hCPCs, and restored SMP30 and mTOR expression. Thus, DOXO-mediated hCPC toxicity is linked to Ca2+-related autophagy signaling, and inhibition of mTOR signaling may provide a cardio-protective effect against DOXO-mediated hCPC toxicity. PMID:27735842
Vinothkumar, M.; Arathi, A.; Joseph, Merin; Nayana, Prasad; Jishma, E. Joshy; Sahana, U.
2016-01-01
Background: Past research studies on the exploration of attributes to the stress of doctors/medical interns were reported more often than the types of coping strategies, healthy practices to strengthen their internal resources to deal effectively with the stressful situations. Objectives: The present study was conducted to find such internal resource – “mindfulness” as a mediator of coping, perceived stress, and job satisfaction among medical interns. Methods: A cross-sectional descriptive study comprised 120 medical interns forms from various medical colleges in Mangalore were recruited and completed the assessment on mindfulness, cognitive-emotive regulation, coping strategies, perceived stress, and job satisfaction from doctoral interns were collected. Results: Initial correlation analysis results indicate that adaptive coping strategies significantly associate with greater mindfulness and less perceived stress. In turn, mindfulness is negatively correlated with nonadaptive coping strategies and perceived. Job satisfaction showed no significant relationship with any of the other variables. Mediational models indicate that the relationship between adaptive coping strategies and perceived stress was significantly mediated by mindfulness. Furthermore, partial mediation between nonadaptive strategies and perceived stress through mindfulness indicates that respondents reported a high level of nonadaptive strategy experience and a lower level of mindfulness can be counterproductive as they encourage the ineffective way to deal with the stresses. Conclusion: The implication of the results were discussed with suggesting a possible intervention to improve the adaptive strategies and mindfulness among the medical interns. PMID:28659700
Seger, Charles R; Banerji, Ishani; Park, Sang Hee; Smith, Eliot R; Mackie, Diane M
2017-08-01
Emotions are increasingly being recognised as important aspects of prejudice and intergroup behaviour. Specifically, emotional mediators play a key role in the process by which intergroup contact reduces prejudice towards outgroups. However, which particular emotions are most important for prejudice reduction, as well as the consistency and generality of emotion-prejudice relations across different in-group-out-group relations, remain uncertain. To address these issues, in Study 1 we examined six distinct positive and negative emotions as mediators of the contact-prejudice relations using representative samples of U.S. White, Black, and Asian American respondents (N = 639). Admiration and anger (but not other emotions) were significant mediators of the effects of previous contact on prejudice, consistently across different perceiver and target ethnic groups. Study 2 examined the same relations with student participants and gay men as the out-group. Admiration and disgust mediated the effect of past contact on attitude. The findings confirm that not only negative emotions (anger or disgust, based on the specific types of threat perceived to be posed by an out-group), but also positive, status- and esteem-related emotions (admiration) mediate effects of contact on prejudice, robustly across several different respondent and target groups.
Practicing more retrieval routes leads to greater memory retention.
Zheng, Jun; Zhang, Wei; Li, Tongtong; Liu, Zhaomin; Luo, Liang
2016-09-01
A wealth of research has shown that retrieval practice plays a significant role in improving memory retention. The current study focused on one simple yet rarely examined question: would repeated retrieval using two different retrieval routes or using the same retrieval route twice lead to greater long-term memory retention? Participants elaborately learned 22 Japanese-Chinese translation word pairs using two different mediators. Half an hour after the initial study phase, the participants completed two retrieval sessions using either one mediator (Tm1Tm1) or two different mediators (Tm1Tm2). On the final test, which was performed 1week after the retrieval practice phase, the participants received only the cue with a request to report the mediator (M1 or M2) followed by the target (Experiment 1) or only the mediator (M1 or M2) with a request to report the target (Experiment 2). The results of Experiment 1 indicated that the participants who practiced under the Tm1Tm2 condition exhibited greater target retention than those who practiced under the Tm1Tm1 condition. This difference in performance was due to the significant disadvantage in mediator retrieval and decoding of the unpracticed mediator under the Tm1Tm1 condition. Although mediators were provided to participants on the final test in Experiment 2, decoding of the unpracticed mediators remained less effective than decoding of the practiced mediators. We conclude that practicing multiple retrieval routes leads to greater memory retention than focusing on a single retrieval route. Thus, increasing retrieval variability during repeated retrieval practice indeed significantly improves long-term retention in a delay test. Copyright © 2016 Elsevier B.V. All rights reserved.
Ali, Disha; Saha, Kuntal K; Nguyen, Phuong H; Diressie, Michael T; Ruel, Marie T; Menon, Purnima; Rawat, Rahul
2013-12-01
Household food insecurity (HFI) is a recognized underlying determinant of child undernutrition, but evidence of associations between HFI and child undernutrition is mixed. The purpose of this study was to investigate if HFI is associated with undernutrition in children aged 6-59.9 mo in Bangladesh (n = 2356), Ethiopia (n = 3422), and Vietnam (n = 3075) and if child dietary diversity (DD) mediated this effect. We used baseline survey data from the Alive & Thrive project. Logistic regression, adjusting for potential confounding factors, was used to determine the magnitude and significance of the association of HFI with stunting, underweight, and wasting. The mediating effect of child DD was tested by using a Sobel-Goodman mediation test. The prevalences of HFI were 66%, 40%, and 32% in Ethiopia, Vietnam, and Bangladesh, respectively. The prevalences of stunting, underweight, and wasting were higher in Bangladesh (47.1%, 43.7%, and 19.1%, respectively) and Ethiopia (50.7%, 27.5%, and 5.9%, respectively) than in Vietnam (20.7%, 15.8%, and 5%, respectively). In the adjusted models, the odds of being stunted or underweight were significantly higher for children in severely food-insecure households in Bangladesh (stunting OR: 1.36; 95% CI: 1.05, 1.76; underweight OR: 1.28; 95% CI: 0.99, 1.65) and Ethiopia (stunting OR: 1.48; 95% CI: 1.09, 2.00; underweight OR: 1.68; 95% CI: 1.22, 2.30) and in moderately food-insecure households in Vietnam (stunting OR: 1.39; 95% CI: 1.16, 1.65; underweight OR: 1.69; 95% CI: 1.28, 2.23). HFI was significantly associated with wasting in Bangladesh where close to 1 in 5 children demonstrated wasting. Child DD did not mediate the relation between HFI and undernutrition in any of the countries. Further research is recommended to investigate potential mediators in this pathway.
Gianotti, Lorena R. R.; Figner, Bernd; Ebstein, Richard P.; Knoch, Daria
2012-01-01
Individuals differ widely in how steeply they discount future rewards. The sources of these stable individual differences in delay discounting (DD) are largely unknown. One candidate is the COMT Val158Met polymorphism, known to modulate prefrontal dopamine levels and affect DD. To identify possible neural mechanisms by which this polymorphism may contribute to stable individual DD differences, we measured 73 participants’ neural baseline activation using resting electroencephalogram (EEG). Such neural baseline activation measures are highly heritable and stable over time, thus an ideal endophenotype candidate to explain how genes may influence behavior via individual differences in neural function. After EEG-recording, participants made a series of incentive-compatible intertemporal choices to determine the steepness of their DD. We found that COMT significantly affected DD and that this effect was mediated by baseline activation level in the left dorsal prefrontal cortex (DPFC): (i) COMT had a significant effect on DD such that the number of Val alleles was positively correlated with steeper DD (higher numbers of Val alleles means greater COMT activity and thus lower dopamine levels). (ii) A whole-brain search identified a cluster in left DPFC where baseline activation was correlated with DD; lower activation was associated with steeper DD. (iii) COMT had a significant effect on the baseline activation level in this left DPFC cluster such that a higher number of Val alleles was associated with lower baseline activation. (iv) The effect of COMT on DD was explained by the mediating effect of neural baseline activation in the left DPFC cluster. Our study thus establishes baseline activation level in left DPFC as salient neural signature in the form of an endophenotype that mediates the link between COMT and DD. PMID:22586360
Moulton, Stuart J; Newman, Emily; Power, Kevin; Swanson, Vivien; Day, Kenny
2015-01-01
The present study examined the relationship between different forms of childhood trauma and eating psychopathology using a multiple mediation model that included emotion dysregulation and dissociation as hypothesised mediators. 142 female undergraduate psychology students studying at two British Universities participated in this cross-sectional study. Participants completed measures of childhood trauma (emotional abuse, physical abuse, sexual abuse, emotional neglect and physical neglect), eating psychopathology, dissociation and emotion dysregulation. Multiple mediation analysis was conducted to investigate the study's proposed model. Results revealed that the multiple mediation model significantly predicted eating psychopathology. Additionally, both emotion dysregulation and dissociation were found to be significant mediators between childhood trauma and eating psychopathology. A specific indirect effect was observed between childhood emotional abuse and eating psychopathology through emotion dysregulation. Findings support previous research linking childhood trauma to eating psychopathology. They indicate that multiple forms of childhood trauma should be assessed for individuals with eating disorders. The possible maintaining role of emotion regulation processes should also be considered in the treatment of eating disorders. Copyright © 2014 Elsevier Ltd. All rights reserved.
Holt, Cheryl L.; Wang, Min Qi; Caplan, Lee; Schulz, Emily; Blake, Victor; Southward, Vivian L.
2013-01-01
The present study tested a mediational model of the role of religious involvement, spirituality, and physical/emotional functioning in a sample of African American men and women with cancer. Several mediators were proposed based on theory and previous research, including sense of meaning, positive and negative affect, and positive and negative religious coping. One hundred patients were recruited through oncologist offices, key community leaders and community organizations, and interviewed by telephone. Participants completed an established measure of religious involvement, the Functional Assessment of Chronic Illness Therapy-Spiritual Well-Being Scale (FACIT-SP-12 version 4), the Positive and Negative Affect Schedule (PANAS), the Meaning in Life Scale, the Brief RCOPE, and the SF-12, which assesses physical and emotional functioning. Positive affect completely mediated the relationship between religious behaviors and emotional functioning. Though several other constructs showed relationships with study variables, evidence of mediation was not supported. Mediational models were not significant for the physical functioning outcome, nor were there significant main effects of religious involvement or spirituality for this outcome. Implications for cancer survivorship interventions are discussed. PMID:21222026
Sapkota, Muna; Kharbanda, Kusum K.; Wyatt, Todd A.
2016-01-01
Background Reactive aldehydes like acetaldehyde and malondialdehyde generated as a result of alcohol metabolism and cigarette smoke exposure lead to the formation of malondialdehyde-acetaldehyde-adducted proteins (MAA adducts). These aldehydes can adduct to different proteins such as bovine serum album (BSA) and surfactant proteins A or D (SPA, SPD). Macrophages play an important role in innate immunity, but the effect of MAA adducts on macrophage function has not yet been examined. Because macrophage scavenger receptor A (SRA; CD204) mediates the uptake of modified proteins, we hypothesized that the effects of MAA modified proteins on macrophage function are primarily mediated through SRA. Methods and Results We tested this hypothesis by exposing SPD-MAA to macrophages and measuring functions. SPD-MAA treatment significantly stimulated pro-inflammatory cytokine TNF-α release in the macrophage cell line, RAW 264.7. A significant reduction in phagocytosis of zymosan particles was also observed. SPD-MAA stimulated a significant dose-dependent increase in TNF-α and IL-6 release from peritoneal macrophages of WT mice. But a significantly less TNF-α and IL-6 were released from peritoneal macrophages of SRA−/− mice. We observed a significant reduction in phagocytosis of zymosan particles in peritoneal macrophages from WT mice treated with SPD-MAA. No further SPD-MAA-induced reduction was seen in peritoneal macrophages form SRA−/− mice. SPD-MAA treatment significantly increased SRA mRNA expression, but had no effect on surface receptor protein expression. Protein kinase C alpha inhibitor and NF-κB inhibitor significantly reduced pro-inflammatory cytokine release in response to SPD-MAA. Conclusion In conclusion, our data demonstrate that SRA is important for MAA-adducted protein-mediated effect on macrophage functions. PMID:27783409
Soysa, Champika K; Azar, Sandra T
2016-01-01
Posttraumatic stress disorder (PTSD) in response to active war is understudied among Sinhalese children in Sri Lanka. We investigated PTSD symptom severity in children using child (n = 60) and mother (n = 60) reports; child-reported war exposure and coping; as well as self-reported maternal PTSD symptom severity. The study addressed active war in 2 rural locations (acute and chronic community war exposure). Child-reports were significantly greater than mother-reports of child PTSD symptom severity. Furthermore, children's war exposure, child-reported and mother-reported child PTSD symptom severity, and maternal PTSD symptom severity were significantly greater in the acute versus chronic community war exposure location, but children's approach and avoidance coping did not significantly differ, indicating a potential ceiling effect. Children's war exposure significantly, positively predicted child-reported child PTSD symptom severity, controlling for age, gender, and maternal PTSD symptom severity, but only maternal PTSD symptom severity significantly, positively predicted mother-reported child PTSD symptom severity. Avoidance coping (in both acute and chronic war) significantly positively mediated the children's war exposure-child-reported child PTSD symptom severity relation, but not mother-reports of the same. Approach coping (in chronic but not acute war) significantly, positively mediated the children's war exposure-child-reported and mother-reported child PTSD symptom severity relations. We advanced the literature on long-term active war by confirming the value of children's self-reports, establishing that both approach and avoidance coping positively mediated the war-exposure-PTSD symptom severity relation, and that the mediation effect of approach coping was situationally moderated by acute verses chronic community war exposure among Sri Lankan children. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
La Barbera, Francesco; Ferrara, Pia Cariota; Boza, Mihaela
2014-12-01
In two experiments, we investigated how priming European identity as common project versus common heritage affects participants' cooperation in a social dilemma; an additional aim was to explore the mediators involved in the process. In the first experiment, 82 students played a public good dilemma with a European bogus partner and then completed self-report measures of identification with the European Union (EU), group-based trust and collective interest. Results showed that priming a common project-based but not a common heritage-based European social identity fostered cooperative behaviour; this effect was mediated by two sequential mediators: the common project prime increased participants' strength of identification with EU (mediator 1) which, in turn, positively affected group-based trust (mediator 2), fostering greater cooperation. Experiment 2 was conducted with a similar procedure on a sample of 124 students, using a different measure of trust and changing the order of mediators. Results supported those of previous experiment: Priming a project-based EU identity content (compared to heritage-based one) had significant direct and indirect effects on cooperation. © 2014 International Union of Psychological Science.
Kim, Paul Youngbin; Park, Irene J K
2009-07-01
Adapting the theory of reasoned action, the present study examined help-seeking beliefs, attitudes, and intent among Asian American college students (N = 110). A multiple mediation model was tested to see if the relation between Asian values and willingness to see a counselor was mediated by attitudes toward seeking professional psychological help and subjective norm. A bootstrapping procedure was used to test the multiple mediation model. Results indicated that subjective norm was the sole significant mediator of the effect of Asian values on willingness to see a counselor. The findings highlight the importance of social influences on help-seeking intent among Asian American college students.
The mediating effect of psychological distress on functional dependence in stroke patients.
Huang, Hui-Chuan; Huang, Li-Kai; Hu, Chaur-Jong; Chang, Chien-Hung; Lee, Hsin-Chien; Chi, Nai-Fang; Shyu, Meei-Ling; Chang, Hsiu-Ju
2014-12-01
To explore varied forms of psychological distress and to determine the mediating influence of psychological distress on functional outcomes in stroke patients. Previous studies attest to the influence of depression on poststroke functional recovery. While there is evidence for neuropathological deficits that occur after stroke to be associated with psychological distress, few studies have explored the effect of various types of psychological distress on functional recovery. A cross-sectional study was used. Data were collected from 178 first-time stroke patients. Study variables included demographic and disease characteristics (stroke location and stroke syndrome classification), psychological distress (the Chinese language version of the Emotional and Social Dysfunction Questionnaire) and functional outcome (Barthel index). Regression and mediation models were used to evaluate the effect of psychological distress on functional outcome. Results revealed that stroke patients experience various forms of mild psychological distress, including anger, helplessness, emotional dyscontrol, indifference, inertia and euphoria, after stroke. Regression and mediation analyses further confirmed that various forms of psychological distress significantly mediated the effect of severe stroke syndromes on functional dependence. The various forms of psychological distress after stroke might play a mediating role in functional recovery and explain how stroke severity affects functional dependence. By understanding the nature of various forms of psychological distress, healthcare professionals should adopt appropriate assessment instruments and design effective interventions to help improve mental and physical function of stroke patients. © 2014 John Wiley & Sons Ltd.
Deane, Kyle; Richards, Maryse; Mozley, Michaela; Scott, Darrick; Rice, Catherine; Garbarino, James
2016-09-02
Exposure to community violence disproportionately impacts low-income, minority youth and is associated with posttraumatic stress symptoms and maladaptive adjustment. This study investigates whether posttraumatic stress mediates the relation between exposure to community violence and externalizing symptoms and the moderating role of family cohesion and daily family support in buffering these effects on later externalizing. Low-income, African American 7th-grade students (M age = 12.57 years; N = 254) from high-crime neighborhoods participated in a 2-year longitudinal study measuring the effects of community violence exposure. The students completed questionnaires administered by research staff over 5 consecutive days for each year of the study. Family cohesion and daily family support exhibited a significant buffering effect for several outcomes. Posttraumatic stress significantly mediated the effect of witnessing community violence on subsequent aggression. The strength of these indirect effects depended on level of family cohesion. The findings provide evidence in support of interventions provided at both individual and family levels. Mental health providers working with this population should be aware of the intertwined nature of exposure to community violence, posttraumatic stress, and subsequent maladaptive outcomes.
Fitzsimmons-Craft, Ellen E.; Bardone-Cone, Anna M.; Bulik, Cynthia M.; Wonderlich, Stephen A.; Crosby, Ross D.; Engel, Scott G.
2014-01-01
Social comparison (i.e., body, eating, exercise) and body surveillance were tested as mediators of the thin-ideal internalization-body dissatisfaction relationship in the context of an elaborated sociocultural model of disordered eating. Participants were 219 college women who completed two questionnaire sessions 3 months apart. The cross-sectional elaborated sociocultural model (i.e., including social comparison and body surveillance as mediators of the thin-ideal internalization-body dissatisfaction relation) provided a good fit to the data, and the total indirect effect from thin-ideal internalization to body dissatisfaction through the mediators was significant. Social comparison emerged as a significant specific mediator while body surveillance did not. The mediation model did not hold prospectively; however, social comparison accounted for unique variance in body dissatisfaction and disordered eating 3 months later. Results suggest that thin-ideal internalization may not be “automatically” associated with body dissatisfaction and that it may be especially important to target comparison in prevention and intervention efforts. PMID:25160010
Wang, Yan; Chen, Xinguang
2015-10-01
Little research has been done on alcohol use and dependence among rural residents in China, a sub-population that might be under increased stress due to the rapid modernization and urbanization processes. We aimed to assess rural residents' levels of stress, negative emotions, resilience, alcohol use/dependence and the complex relationships among them. Survey data from a large random sample (n=1145, mean age=35.9, SD=7.7, 50.7% male) of rural residents in Wuhan, China were collected using Audio Computer-Assisted Self-Interview. The sample had high prevalence of frequently perceived stress (47%) and high prevalence of ever (54.4%), past 30-day (40.4%), and binge drinking (13.8%). Approximately 11% met the criterion for intermediate to severe alcohol dependence. Mediation analysis indicated that the association between perceived stress (predictor) and alcohol dependence (outcome) was fully mediated by anxiety (indirect effect=.203, p<.01) and depression (indict effect=.158, p<.05); moderation analysis indicated that association between stress and two negative emotions (mediators) was significantly modified by resilience (moderator); an integrative moderated mediation analysis indicated that the indirect effect from stress to alcohol dependence through negative emotions was also moderated by resilience. Negative emotions play a key role in bridging stress and alcohol dependence, while resilience significantly buffers the impact of stress on depression, reducing the risk of alcohol dependence. Resilience training may be an effective component for alcohol intervention in rural China. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Mediating pathways and gender differences between shift work and subjective cognitive function.
Wong, Imelda S; Smith, Peter M; Ibrahim, Selahadin; Mustard, Cameron A; Gignac, Monique A M
2016-11-01
Increased injury risk among shift workers is often attributed to cognitive function deficits that come about as a result of sleep disruptions. However, little is known about the intermediate influences of other factors (eg, work stress, health) which may affect this relationship. In addition, gender differences in these the complex relationships have not been fully explored. The purpose of this study is to (1) identify the extent to which work and non-work factors mediate the relationship between shift work, sleep and subsequent subjective cognitive function; and (2) determine if the mediating pathways differ for men and women. Data from the 2010 National Population Health Survey was used to create a cross-sectional sample of 4255 employed Canadians. Using path modelling, we examined the direct and indirect relationships between shift work, sleep duration, sleep quality and subjective cognitive function. Multigroup analyses tested for significantly different pathways between men and women. Potential confounding effects of age and self-reported health and potential mediating effects of work stress were simultaneously examined. Work stress and sleep quality significantly mediated the effects of shift work on cognition. Age and health confounded the relationship between sleep quality and subjective cognition. No differences were found between men and women. Occupational health and safety programmes are needed to address stress and health factors, in addition to sleep hygiene, to effectively address cognitive function among shift workers. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Goodin, Burel R; McGuire, Lynanne M; Stapleton, Laura M; Quinn, Noel B; Fabian, Lacy A; Haythornthwaite, Jennifer A; Edwards, Robert R
2009-11-01
To investigate the cross-sectional associations among self-reported weekly strenuous exercise bouts, anxiety sensitivity, and their interaction with pain catastrophizing and pain responses to the cold pressor task (CPT) in healthy, ethnically diverse young adults (n = 79). Exercise involvement has been shown to have hypoalgesic effects and cognitive factors may partially explain this effect. Particularly, alterations in pain catastrophizing have been found to mediate the positive pain outcomes of multidisciplinary treatments incorporating exercise. Further, recent evidence suggests that exercise involvement and anxiety sensitivity may act together, as interacting factors, to exert an effect on catastrophizing and pain outcomes; however, further research is needed to clarify the nature of this interaction. Before the CPT, participants were asked to complete the Godin Leisure-Time Exercise Questionnaire, the Beck Depression Inventory, and the Anxiety Sensitivity Index. After the CPT, participants completed a modified version of the Pain Catastrophizing Scale and the Short Form-McGill Pain Questionnaire. At a high level of anxiety sensitivity, controlling for depressive symptoms, CPT immersion time, and sex differences, a bias-corrected (BC), bootstrapped confidence interval revealed that pain catastrophizing significantly mediated the relationship between self-reported weekly strenuous exercise bouts and pain response (95% BC Confidence Interval = -9.558, -0.800 with 1000 resamples). At intermediate and low levels of anxiety sensitivity, no significant mediation effects were found. These findings support that, for pain catastrophizing to mediate the strenuous exercise-pain response relation, individuals must possess a high level of anxiety sensitivity.
Springvloet, Linda; Lechner, Lilian; Candel, Math J J M; de Vries, Hein; Oenema, Anke
2016-03-01
This study explored whether the determinants that were targeted in two versions of a Web-based computer-tailored nutrition education intervention mediated the effects on fruit, high-energy snack, and saturated fat intake among adults who did not comply with dietary guidelines. A RCT was conducted with a basic (tailored intervention targeting individual cognitions and self-regulation), plus (additionally targeting environmental-level factors), and control group (generic nutrition information). Participants were recruited from the general Dutch adult population and randomly assigned to one of the study groups. Online self-reported questionnaires assessed dietary intake and potential mediating variables (behavior-specific cognitions, action- and coping planning, environmental-level factors) at baseline and one (T1) and four (T2) months post-intervention (i.e. four and seven months after baseline). The joint-significance test was used to establish mediating variables at different time points (T1-mediating variables - T2-intake; T1-mediating variables - T1-intake; T2-mediating variables - T2-intake). Educational differences were examined by testing interaction terms. The effect of the plus version on fruit intake was mediated (T2-T2) by intention and fruit availability at home and for high-educated participants also by attitude. Among low/moderate-educated participants, high-energy snack availability at home mediated (T1-T1) the effect of the basic version on high-energy snack intake. Subjective norm mediated (T1-T1) the effect of the basic version on fat intake among high-educated participants. Only some of the targeted determinants mediated the effects of both intervention versions on fruit, high-energy snack, and saturated fat intake. A possible reason for not finding a more pronounced pattern of mediating variables is that the educational content was tailored to individual characteristics and that participants only received feedback for relevant and not for all assessed mediating variables. Netherlands Trial Registry NTR3396. Copyright © 2015. Published by Elsevier Ltd.
Moodie, Sue; Ialongo, Nick; López, Patricia; Rosado, Jorge; García-Vargas, Gonzalo; Ronquillo, Dolores; Kordas, Katarzyna
2013-01-01
A range of studies has been conducted on the detrimental effects of lead in mining and smelting communities. The neurocognitive and behavioural health effects of lead on children are well known. This research characterized the conjoint influence of lead exposure and home enriched environment on neurocognitive function and behaviour for first-grade children living in a Mexican lead smelter community. Structural equation models were used for this analysis with latent outcome variables, Cognition and Behaviour, constructed based on a battery of assessments administered to the first-grade children, their parents, and teachers. Structural equation modelling was used to describe complex relationships of exposure and health outcomes in a manner that permitted partition of both direct and indirect effects of the factors being measured. Home Environment (a latent variable constructed from information on mother's education and support of school work and extracurricular activities), and child blood lead concentration each had a main significant effect on cognition and behaviour. However, there were no statistically significant moderation relationships between lead and Home Environment on these latent outcomes. Home Environment had a significant indirect mediation effect between lead and both Cognition and Behaviour (p-value<0.001). The mediation model had a good fit with Root Mean Square Error of Approximation <0.0001 and a Weighted Root Mean Square Residual of 0.895. These results were highly significant and suggest that Home Environment has a moderate mediation effect with respect to lead effects on Behaviour (β=0.305) and a lower mediation effect on Cognition (β=0.184). The extent of home enrichment in this study was most highly related to the mother's support of schoolwork and slightly less by the mother's support of extracurricular activities or mother's education. Further research may be able to develop approaches to support families to make changes within their home and child rearing practices, or advocate for different approaches to support their child's behaviour to reduce the impact of lead exposure on children's cognitive and behavioural outcomes. Copyright © 2012 Elsevier Inc. All rights reserved.
Robinson, Kristen E; Fountain-Zaragoza, Stephanie; Dennis, Maureen; Taylor, H Gerry; Bigler, Erin D; Rubin, Kenneth; Vannatta, Kathryn; Gerhardt, Cynthia A; Stancin, Terry; Yeates, Keith Owen
2014-11-15
This study examined whether executive function and theory of mind mediate the effects of pediatric traumatic brain injury (TBI) on social adjustment, relative to children with orthopedic injury (OI). Participants included 19 children with severe TBI, 41 children with complicated mild/moderate TBI, and 57 children with OI. They completed measures of executive function, as well as cognitive, affective, and conative theory of mind. Parents provided ratings of children's social adjustment. Children with severe TBI performed more poorly than children with OI on executive function and theory of mind tasks and were rated by parents as having more behavioral symptoms and worse communication and social skills. Executive function and theory of mind were positively correlated with social skills and communication skills, and negatively correlated with behavioral symptoms. In multiple mediator models, theory of mind and executive function were not significant direct predictors of any measure of social adjustment, but mediated the association between injury and adjustment for children with severe TBI. Theory of mind was a significant independent mediator when predicting social skills, but executive function was not. TBI in children, particularly severe injury, is associated with poor social adjustment. The impact of TBI on children's social adjustment is likely mediated by its effects on executive function and theory of mind.
Fountain-Zaragoza, Stephanie; Dennis, Maureen; Taylor, H. Gerry; Bigler, Erin D.; Rubin, Kenneth; Vannatta, Kathryn; Gerhardt, Cynthia A.; Stancin, Terry; Yeates, Keith Owen
2014-01-01
Abstract This study examined whether executive function and theory of mind mediate the effects of pediatric traumatic brain injury (TBI) on social adjustment, relative to children with orthopedic injury (OI). Participants included 19 children with severe TBI, 41 children with complicated mild/moderate TBI, and 57 children with OI. They completed measures of executive function, as well as cognitive, affective, and conative theory of mind. Parents provided ratings of children's social adjustment. Children with severe TBI performed more poorly than children with OI on executive function and theory of mind tasks and were rated by parents as having more behavioral symptoms and worse communication and social skills. Executive function and theory of mind were positively correlated with social skills and communication skills, and negatively correlated with behavioral symptoms. In multiple mediator models, theory of mind and executive function were not significant direct predictors of any measure of social adjustment, but mediated the association between injury and adjustment for children with severe TBI. Theory of mind was a significant independent mediator when predicting social skills, but executive function was not. TBI in children, particularly severe injury, is associated with poor social adjustment. The impact of TBI on children's social adjustment is likely mediated by its effects on executive function and theory of mind. PMID:25003478
Jacobs, Ingo; Wollny, Anna; Sim, Chu-Won; Horsch, Antje
2016-06-01
In the present study, we tested a serial mindfulness facets-trait emotional intelligence (TEI)-emotional distress-multiple health behaviors mediation model in a sample of N = 427 German-speaking occupational therapists. The mindfulness facets-TEI-emotional distress section of the mediation model revealed partial mediation for the mindfulness facets Act with awareness (Act/Aware) and Accept without judgment (Accept); inconsistent mediation was found for the Describe facet. The serial two-mediator model included three mediational pathways that may link each of the four mindfulness facets with multiple health behaviors. Eight out of 12 indirect effects reached significance and fully mediated the links between Act/Aware and Describe to multiple health behaviors; partial mediation was found for Accept. The mindfulness facet Observe was most relevant for multiple health behaviors, but its relation was not amenable to mediation. Implications of the findings will be discussed. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.
Empathy Mediates the Effects of Age and Sex on Altruistic Moral Decision Making.
Rosen, Jan B; Brand, Matthias; Kalbe, Elke
2016-01-01
Moral decision making involves affective and cognitive functions like emotional empathy, reasoning and cognitive empathy/theory of mind (ToM), which are discussed to be subject to age-related alterations. Additionally, sex differences in moral decision making have been reported. However, age-related changes in moral decision making from early to late adulthood and their relation to sex and neuropsychological functions have not been studied yet. One hundred ninety seven participants (122 female), aged 19-86 years, were tested with a moral decision making task comprising forced choice "everyday life" situations in which an altruistic option that favors a socially accepted alternative had to be considered against an egoistic option that favors personal benefit over social interests. The percentage of altruistic decisions was analyzed. A structural equation model (SEM) was calculated to test the hypothesis whether age and sex predict altruistic moral decision, and whether relevant neuropsychological domains mediate these hypothesized relationships. A significant relationship between age and moral decision making was found indicating more frequent altruistic decisions with increasing age. Furthermore, women decided more altruistically than men. The SEM showed that both age and sex are significant predictors of altruistic moral decision making, mediated by emotional empathy but not by reasoning. No cognitive empathy and ToM scores were correlated to age and moral decision making at the same time and thus were not included in the SEM. Our data suggest that increasing age and female sex have an effect on altruistic moral decisions, but that this effect is fully mediated by emotional empathy. The fact that changes of moral decision making with age are mediated by emotional empathy can be interpreted in the light of the so-called "positivity effect" and increasing avoidance of negative affect in aging. The mediated sex effect might represent both biological aspects and socialized sex roles for higher emotional empathy leading to more altruistic decisions.
Kandler, Christian; Riemann, Rainer
2013-07-01
In the current study, we examined the genetic and environmental sources of the links between individual religiousness and individual personality traits, perceived parental religiousness, and perceived peer religiousness. Data from 870 individuals (incl. 394 twin pairs) were analyzed. Variance in individual religiousness was significantly influenced by genetic effects, environmental influences shared by twins reared together, and individual-specific environmental influences. Individual religiousness showed significant associations with age, sex, specific personality traits (e.g., agreeableness, openness to values), and perceived religiousness of important social interaction partners, such as parents, best friends, and spouses. The links to personality traits were relatively small and primarily genetically mediated. The associations between individual religiousness and parental religiousness were substantial and mediated by shared environmental effects. These links significantly decreased across age accompanying a significant decrease of shared environmental influences on individual religiousness. The correlations between individual religiousness and perceived religiousness of spouses and best friends were relatively moderate but increased with age. These associations were mediated by genetic as well as nonshared environmental sources accompanying an increase of nonshared environmental influences on individual religiousness with age. The results suggest that inter-individual differences in religiousness are due to multiple sources.
Linking childhood abuse and hypertension: sleep disturbance and inflammation as mediators.
Petrov, Megan E; Davis, Mary C; Belyea, Michael J; Zautra, Alex J
2016-08-01
The indirect association of childhood abuse with prevalent hypertension in adulthood through sleep disturbance and pro-inflammatory biomarkers was investigated in 589 community-dwelling, middle-aged adults. Participants completed the Childhood Trauma Questionnaire and self-reported current sleep disturbance and medical diagnoses including hypertension. Blood pressure was taken and blood samples were analyzed for C-reactive protein, interleukin-6, and fibrinogen. Hypertension was present in 41.3 % of the sample. In the full multiple mediation model, tested using structural equation modeling, all hypothesized pathways were significant (p's < 0.05). Childhood abuse was significantly related to both body mass index and sleep disturbance, which, both in turn, were significantly associated with inflammation, which was subsequently associated with hypertension status. The model demonstrated good fit [χ(2) (122) = 352.0, p < 0.001, CFI = 0.918, RMSEA = 0.057] and the indirect effect of all mediators was significant (indirect effect: 0.02, 95 % CI 0.005-0.03, p = 0.001). Sleep disturbance, body mass, and inflammation may be independent, intermediate steps between childhood abuse and subsequent hypertension that may be amenable to biobehavioral interventions.
Quercetin Potentiates Doxorubicin Mediated Antitumor Effects against Liver Cancer through p53/Bcl-xl
Wang, Guanyu; Sharma, Sherven; Dong, Qinghua
2012-01-01
Background The dose-dependent toxicities of doxorubicin (DOX) limit its clinical applications, particularly in drug-resistant cancers, such as liver cancer. In this study, we investigated the role of quercetin on the antitumor effects of DOX on liver cancer cells and its ability to provide protection against DOX-mediated liver damage in mice. Methodology and Results The MTT and Annexin V/PI staining assay demonstrated that quercetin selectively sensitized DOX-induced cytotoxicity against liver cancer cells while protecting normal liver cells. The increase in DOX-mediated apoptosis in hepatoma cells by quercetin was p53-dependent and occurred by downregulating Bcl-xl expression. Z-VAD-fmk (caspase inhibitor), pifithrin-α (p53 inhibitor), or overexpressed Bcl-xl decreased the effects of quercetin on DOX-mediated apoptosis. The combined treatment of quercetin and DOX significantly reduced the growth of liver cancer xenografts in mice. Moreover, quercetin decreased the serum levels of alanine aminotransferase and aspartate aminotransferase that were increased in DOX-treated mice. Quercetin also reversed the DOX-induced pathological changes in mice livers. Conclusion and Significance These results indicate that quercetin potentiated the antitumor effects of DOX on liver cancer cells while protecting normal liver cells. Therefore, the development of quercetin may be beneficial in a combined treatment with DOX for increased therapeutic efficacy against liver cancer. PMID:23240061
Mitra, Satabdi; Sarkar, Aditya Prasad; Haldar, Dibakar; Saren, Asit Baren; Lo, Sourav; Sarkar, Gautam Narayan
2018-01-01
Perceived stress and burnout are by-products of powerless responsibility imposed on resident doctors. Emotional intelligence (EI) works as an adapting and coping tool. The objective of this study is to find out the role of work-related perceived stress on burnout and influence of EI on it. A descriptive cross-sectional study was conducted from February to April 2016 among 63 resident doctors of different departments of Bankura Sammilani Medical College and Hospital. Data were collected through a self-administered questionnaire for background characteristics and work-related variables. Cohen perceived stress scale, Trait EI, and Shirom-Melamed burnout questionnaire were applied for measuring perceived stress, EI, and burnout, respectively. Statistical analysis was done with of SPSS version 22.0, and for mediation analysis, Andrew F. Hyne's SPSS macro was adopted. Nonparametric bootstrapping was done assuming small sample. Out of complete responses, 67%, 22.9%, and 9.8% were from clinical, paraclinical, and preclinical specialties, respectively. Burnout had a significant positive correlation with perceived stress and in negative correlation with EI-well-being and positive correlation with EI-self-control and sociability. Physical fatigue factor of burnout had a significant positive correlation with EI-emotionality. Perceived stress had a negative correlation with EI-well-being. On mediation analysis, assuming EI as a mediator, total, direct, and indirect effects of perceived stress on burnout were significant (<0.05). Mediation was proved to act with percent mediation of 0.07. There was definite mitigating effect of EI on burnout by perceived stress among resident doctors. This necessitates more attention by decision-makers toward this burning problem for the sake of care of caregivers.
Meng, Kang; Lü, Shu-Zheng; Zhu, Hua-Gang; Chen, Xin; Ge, Chang-Jiang; Song, Xian-Tao
2010-12-01
Adenosine phosphate-mediated platelet aggregation is a prognostic factor for major adverse cardiac events in patients who have undergone selective percutaneous coronary interventions. This study aimed to assess whether an adjusted loading dose of clopidogrel could more effectively inhibit platelet aggregation in patients undergoing selected percutaneous coronary intervention. A total of 205 patients undergoing selected percutaneous coronary intervention were enrolled in this multicenter, prospective, randomized study. Patients receiving domestic clopidogrel (n = 104) served as the Talcom (Taijia) group; others (n = 101) received Plavix, the Plavix group. Patients received up to 3 additional 300-mg loading doses of clopidogrel to decrease the adenosine phosphate-mediated platelet aggregation index by more than 50% (the primary endpoint) compared with the baseline. The secondary endpoint was major adverse cardiovascular events at 12 months. Compared with the rational loading dosage, the tailored loading dosage better inhibited platelet aggregation based on a > 50% decrease in adenosine phosphate-mediated platelet aggregation (rational loading dosage vs. tailored loading dosage, 48% vs. 73%, P = 0.028). There was no significant difference in the eligible index between the Talcom and Plavix groups (47% vs. 49% at 300 mg; 62% vs. 59% at 600 mg; 74% vs. 72% at 900 mg; P > 0.05) based on a standard adenosine diphosphate-mediated platelet aggregation decrease of > 50%. After 12 months of follow-up, there were no significant differences in major adverse cardiac events (2.5% vs. 2.9%, P = 5.43). No acute or subacute stent thrombosis events occurred. An adjusted loading dose of clopidogrel could have significant effects on antiplatelet aggregation compared with a rational dose, decreasing 1-year major adverse cardiac events in patients undergoing percutaneous coronary interventions based on adenosine phosphate-mediated platelet aggregation with no increase in bleeding.
Chan, Wai Sze; Williams, Jacob; Dautovich, Natalie D.; McNamara, Joseph P.H.; Stripling, Ashley; Dzierzewski, Joseph M.; Berry, Richard B.; McCoy, Karin J.M.; McCrae, Christina S.
2017-01-01
Study Objectives: Sleep variability is a clinically significant variable in understanding and treating insomnia in older adults. The current study examined changes in sleep variability in the course of brief behavioral therapy for insomnia (BBT-I) in older adults who had chronic insomnia. Additionally, the current study examined the mediating mechanisms underlying reductions of sleep variability and the moderating effects of baseline sleep variability on treatment responsiveness. Methods: Sixty-two elderly participants were randomly assigned to either BBT-I or self-monitoring and attention control (SMAC). Sleep was assessed by sleep diaries and actigraphy from baseline to posttreatment and at 3-month follow-up. Mixed models were used to examine changes in sleep variability (within-person standard deviations of weekly sleep parameters) and the hypothesized mediation and moderation effects. Results: Variabilities in sleep diary-assessed sleep onset latency (SOL) and actigraphy-assessed total sleep time (TST) significantly decreased in BBT-I compared to SMAC (Pseudo R2 = .12, .27; P = .018, .008). These effects were mediated by reductions in bedtime and wake time variability and time in bed. Significant time × group × baseline sleep variability interactions on sleep outcomes indicated that participants who had higher baseline sleep variability were more responsive to BBT-I; their actigraphy-assessed TST, SOL, and sleep efficiency improved to a greater degree (Pseudo R2 = .15 to .66; P < .001 to .044). Conclusions: BBT-I is effective in reducing sleep variability in older adults who have chronic insomnia. Increased consistency in bedtime and wake time and decreased time in bed mediate reductions of sleep variability. Baseline sleep variability may serve as a marker of high treatment responsiveness to BBT-I. Clinical Trial Registration: ClinicalTrials.gov, Identifier: NCT02967185 Citation: Chan WS, Williams J, Dautovich ND, McNamara JP, Stripling A, Dzierzewski JM, Berry RB, McCoy KJ, McCrae CS. Night-to-night sleep variability in older adults with chronic insomnia: mediators and moderators in a randomized controlled trial of brief behavioral therapy (BBT-I). J Clin Sleep Med. 2017;13(11):1243–1254. PMID:28992829
Majd Ara, Elahe; Talepasand, Siavash; Rezaei, Ali Mohammad
2017-06-01
The present study was conducted with the aim of examining the structural model of interpersonal relationships and depression using coping strategies and loneliness as mediators. Using multistage random sampling, 301 high-school students were selected from Minudasht city, Iran. The participants were aksed to complete the Network of Relationships Inventory (NRI); the Ways of Coping Questionnaire (Lazarus and Folkman); the Children's Loneliness Scale (CLS); and the Depression, Anxiety, and Stress Scale (DASS-21). Structural equation modeling was used to examine the pattern of direct and indirect effects. Findings of the present study show that the data are well fitted to the model. The indirect effect of the positive quality of relationships was significant on depression through loneliness. Moreover, the indirect effects of the negative quality of relationships on depression through loneliness and through emotion-focused coping strategies were statistically significant. Although the effect of loneliness and emotion-focused coping strategies on depression was significant, problem-focused coping strategies did not have a significant effect on depression. Additionally, the findings suggested that the indirect effect through loneliness on depression was stronger compared with the indirect effect through emotion-focused coping strategies. The positive or negative quality of interpersonal relationships, loneliness, and emotion-focused coping strategy can significantly predict depression.
Sharbanee, Jason M.; Hu, Litje; Stritzke, Werner G. K.; Wiers, Reinout W.; Rinck, Mike; MacLeod, Colin
2014-01-01
Training people to respond to alcohol images by making avoidance joystick movements can affect subsequent alcohol consumption, and has shown initial efficacy as a treatment adjunct. However, the mechanisms that underlie the training’s efficacy are unknown. The present study aimed to determine 1) whether the training’s effect is mediated by a change in action tendency or a change in selective attention, and 2) whether the training’s effect is moderated by individual differences in working memory capacity (WMC). Three groups of social drinkers (total N = 74) completed either approach-alcohol training, avoid-alcohol training or a sham-training on the Approach-Avoidance Task (AAT). Participants’ WMC was assessed prior to training, while their alcohol-related action tendency and selective attention were assessed before and after the training on the recently developed Selective-Attention/Action Tendency Task (SA/ATT), before finally completing an alcohol taste-test. There was no significant main effect of approach/avoidance training on alcohol consumption during the taste-test. However, there was a significant indirect effect of training on alcohol consumption mediated by a change in action tendency, but no indirect effect mediated by a change in selective attention. There was inconsistent evidence of WMC moderating training efficacy, with moderation found only for the effect of approach-alcohol training on the AAT but not on the SA/ATT. Thus approach/avoidance training affects alcohol consumption specifically by changing the underlying action tendency. Multiple training sessions may be required in order to observe more substantive changes in drinking behaviour. PMID:24465750
Sanders, Jasmyn; Hershberger, Alexandra R; Kolp, Haley M; Um, Miji; Aalsma, Matthew; Cyders, Melissa A
2017-01-01
Juvenile justice-involved youth face disproportionate rates of sexual abuse, which increases the risk of post-traumatic stress disorder (PTSD) and substance use disorders (SUDs), both of which are associated with poor long-term outcomes. The present study tested two mediation and moderation models, controlling for age, race, and history of physical abuse, with gender as a moderator, to determine whether PTSD symptoms serve as a risk factor and/or mechanism in the relationship between sexual abuse and substance use. Data were examined for 197 juvenile justice-involved youth (mean age = 15.45, 68.9% non-White, 78.4% male) that completed court-ordered psychological assessments. Results indicated that PTSD symptoms significantly mediated the relationship between sexual abuse and drug (β = 3.44, confidence interval [CI] [0.26, 7.41]; test for indirect effect z = 2.41, p = .02) and alcohol use (β = 1.42, CI [0.20, 3.46]; test for indirect effect z = 2.23, p = .03). PTSD symptoms and gender were not significant moderators. Overall, PTSD symptoms mediate the relationship between sexual abuse and SUDs in juvenile justice-involved youth, which suggests viability of targeting PTSD symptoms as a modifiable risk factor to reduce the effects of sexual abuse on substance use in this high-risk population.
Red-koji fermented red ginseng ameliorates high fat diet-induced metabolic disorders in mice.
Kim, Chang Man; Yi, Seong Joon; Cho, Il Je; Ku, Sae Kwang
2013-10-30
Fermentation of medicinal herbs improves their pharmacological efficacy. In this study, we investigated the effects of red-koji fermented red ginseng (fRG) on high-fat diet (HFD)-mediated metabolic disorders, and those effects were compared to those of non-fermented red ginseng (RG). fRG (500, 250 or 125 mg/kg), RG (250 mg/kg), simvastatin (10 mg/kg), silymarin (100 mg/kg) and metformin (250 mg/kg) were orally administered from 1 week after initiation of HFD supply for 84 days. The diameter of adipocytes in periovarian and abdominal fat pads and the thickness of the abdominal fat were significantly decreased by fRG treatment, while HFD-mediated weight gain was partly alleviated by fRG in a dose-dependent manner. Moreover, biochemical and histomorphometrical analyses clearly indicated that fRG significantly inhibited HFD-induced metabolic disorders such as hyperglycemia, hyperlipidemia, hepatopathy and nephropathy in a dose-dependent manner. More favorable pharmacological effects on HFD-mediated metabolic disorders were also observed with fRG compared to an equal dose of RG. This finding provides direct evidence that the pharmacological activities of RG were enhanced by red-koji fermentation, and fRG could be a neutraceutical resource for the alleviation of obesity-mediated metabolic disorders.
Personal and Environmental Resources Mediate the Positivity-Emotional Dysfunction Relationship.
Lehrer, H Matthew; Janus, Katherine C; Gloria, Christian T; Steinhardt, Mary A
2017-03-01
We investigated the relationships among positivity, perceived personal and environmental resources, and emotional dysfunction in adolescent girls. We hypothesized that perceived resources would mediate the relationship between positivity and emotional dysfunction. Participants (N = 510) attending an all-girls public school completed a survey assessing emotional dysfunction (depressive symptoms and perceived stress), positivity (positive/negative emotions), and personal/ environmental resources (resilience, hope, percent adaptive coping, community connectedness, social support, and school connectedness). Perceived resources were combined into one latent variable, and structural equation modeling tested the mediating effect of perceived resources on the relationship between positivity and emotional dysfunction. The model accounted for 63% of the variance in emotional dysfunction. Positivity exerted a significant direct effect on emotional dysfunction (β = -.14, p < .01), but its influence was primarily mediated through perceived resources (indirect effect: β = -.43, p < .001). The impact of positivity on emotional dysfunction is primarily but not entirely mediated by perceived personal and environmental resources. Schools should consider strategies to enhance experiences of positive emotions and/or decrease experiences of negative emotions, in conjunction with encouraging student awareness and development of personal and environmental resources.
Molecular simulation of the effect of cholesterol on lipid-mediated protein-protein interactions.
de Meyer, Frédérick J-M; Rodgers, Jocelyn M; Willems, Thomas F; Smit, Berend
2010-12-01
Experiments and molecular simulations have shown that the hydrophobic mismatch between proteins and membranes contributes significantly to lipid-mediated protein-protein interactions. In this article, we discuss the effect of cholesterol on lipid-mediated protein-protein interactions as function of hydrophobic mismatch, protein diameter and protein cluster size, lipid tail length, and temperature. To do so, we study a mesoscopic model of a hydrated bilayer containing lipids and cholesterol in which proteins are embedded, with a hybrid dissipative particle dynamics-Monte Carlo method. We propose a mechanism by which cholesterol affects protein interactions: protein-induced, cholesterol-enriched, or cholesterol-depleted lipid shells surrounding the proteins affect the lipid-mediated protein-protein interactions. Our calculations of the potential of mean force between proteins and protein clusters show that the addition of cholesterol dramatically reduces repulsive lipid-mediated interactions between proteins (protein clusters) with positive mismatch, but does not affect attractive interactions between proteins with negative mismatch. Cholesterol has only a modest effect on the repulsive interactions between proteins with different mismatch. Copyright © 2010 Biophysical Society. Published by Elsevier Inc. All rights reserved.
N’cho, Hammad S.; Green, Carlton E.; Jernigan, Maryam M.; Helms, Janet E.
2016-01-01
Discrimination is related to depression and poor self-esteem among Black men. Poorer self-esteem is also associated with depression. However, there is limited research identifying how self-esteem may mediate the associations between discrimination and depressive symptoms for disparate ethnic groups of Black men. The purpose of this study was to examine ethnic groups as a moderator of the mediating effects of self-esteem on the relationship between discrimination and depressive symptoms among a nationally representative sample of African American (n=1,201) and Afro-Caribbean American men (n=545) in the National Survey of American Life. Due to cultural socialization differences, we hypothesized that self-esteem would mediate the associations between discrimination and depressive symptoms only for African American men, but not Afro-Caribbean American men. Moderated-mediation regression analyses indicated that the conditional indirect effects of discrimination on depressive symptoms through self-esteem were significant for African American men, but not for Afro-Caribbean men. Our results highlight important ethnic differences among Black men. PMID:27337623
Intergenerational Continuity in Parenting Behavior: Mediating Pathways and Child Effects
Neppl, Tricia K.; Conger, Rand D.; Scaramella, Laura V.; Ontai, Lenna L.
2009-01-01
This prospective, longitudinal investigation examined mechanisms proposed to explain continuities in parenting behavior across two generations (G1, G2). Data came from 187 G2 adults, their mothers (G1), and their children (G3). Prospective information regarding G2 was collected both during adolescence and early adulthood. G1 data were collected during G2’s adolescence and G3 data were generated during the preschool years. Assessments included both observational and self-report measures. The results indicated a direct relationship between G1 and G2 harsh parenting and between G1 and G2 positive parenting. As predicted, specific mediators accounted for intergenerational continuity in particular types of parenting behavior. G2 externalizing behavior mediated the relationship between G1 and G2 harsh parenting, while G2 academic attainment mediated the relationship between G1 and G2 positive parenting. In addition, the hypothesized mediating pathways remained statistically significant after taking into account possible G2 effects on G1 parenting and G3 effects on G2 parenting. PMID:19702389
Lin, Heng; Yu, Chun-Hsien; Jen, Chih-Yu; Cheng, Ching-Feng; Chou, Ying; Chang, Chih-Cheng; Juan, Shu-Hui
2010-01-01
Protective effects of adiponectin (APN; an adipocytokine) were shown against various oxidative challenges; however, its therapeutic implications and the mechanisms underlying hepatic iron overload remain unclear. Herein, we show that the deleterious effects of iron dextran on liver function and iron deposition were significantly reversed by adiponectin gene therapy, which was accompanied by AMP-activated protein kinase (AMPK) phosphorylation and heme oxygenase (HO)-1 induction. Furthermore, AMPK-mediated peroxisome proliferator-activated receptor-α (PPARα) activation by APN was ascribable to HO-1 induction. Additionally, we revealed direct transcriptional regulation of HO-1 by the binding of PPARα to a PPAR-responsive element (PPRE) by various experimental assessments. Interestingly, overexpression of HO-1 in hepatocytes mimicked the protective effect of APN in attenuating iron-mediated injury, whereas it was abolished by SnPP and small interfering HO-1. Furthermore, bilirubin, the end-product of the HO-1 reaction, but not CO, protected hepatocytes from iron dextran-mediated caspase activation. Herein, we demonstrate a novel functional PPRE in the promoter regions of HO-1, and APN-mediated HO-1 induction elicited an antiapoptotic effect and a decrease in iron deposition in hepatocytes subjected to iron challenge. PMID:20709802
Adams, Marc A; Norman, Gregory J; Hovell, Melbourne F; Sallis, James F; Patrick, Kevin
2009-03-01
The Transtheoretical model (TTM) integrates principles of operant learning, such as stimulus control and reinforcement, and psychological factors, such as decisional balance. Understanding interrelationships between decisions, behavior, and consequences from multiple-theoretical perspectives can advance theory and inform development of more effective interventions. This analysis examined the mediating effects of a special case of the decisional balance construct in which the pros of competing behaviors (i.e., sun protection vs. exposure) were measured rather than the pros and cons of the same behavior. Participants included 819 adolescents (10 to 16 years old, 53.5% girls, 58.4% White) randomized to a 24-month expert system intervention (SunSmart) or a physical activity and nutrition comparison group. Self-report measures included sun protection behaviors, pros for protection, and pros for exposure. Mediation analysis using latent growth curve models found both the treatment-to-mediator and mediator-to-behavior paths significant for decisional balance, producing an indirect effect of .323 (p < .01) and good model fit (CFI = .973, RMSEA = .055). Multiple strategies for conceptualizing and measuring decisional balance appear to be valid. Results are interpreted from the TTM and operant perspectives. (c) 2009 APA, all rights reserved
Gao, Meng; Li, Yu-Chen; Zhang, Wei
2017-04-01
To examine the mediating effect of self-concept between interparental conflict and mental health in children and adolescents. A total of 689 students (10-18 years) were surveyed using the convenient sampling method, and their mental health, self-concept, and interparental conflict were examined by the general status questionnaire, Strengths and Difficulties Questionnaire, Self-Description Questionnaire, and Children's Perception of Interparental Conflict Scale. Structural equation modeling (SEM) and simultaneous analysis of several groups were used to construct the mediator model and analyze the data, respectively. The Bootstrap method was used to assess the significance of the mediating effects. Interparental conflict was positively correlated with mental health of children and adolescents (P<0.05), but was negatively correlated with self-concept (P<0.01). Self-concept was negatively correlated with mental health (P<0.01). Self-concept had a partial (60%) mediating effect between interparental conflict and mental health. Academic stage, but not gender, had a regulatory role on interparental conflict, mental health, and self-concept. Self-concept plays an important role between interparental conflict and mental health. It is necessary to improve self-concept level in children and adolescents exposed to interparental conflict.
Anderson, Mary; Gandhi, Pranav; Tuli, Sanjeev; Krull, Kevin; Lai, Jin-Shei; Nackashi, John; Shenkman, Elizabeth
2013-01-01
Objective To examine the relationships among pediatric fatigue, health-related quality of life (HRQOL), and family impact among children with special health care needs (CSHCNs), specifically whether HRQOL mediates the influence of fatigue on family impact. Methods 266 caregivers of CSHCNs were studied. The Pediatric Quality of Life Inventory Multidimensional Fatigue Scale, Pediatric Quality of Life Inventory Generic Scale, and Impact on Family Scale were used to measure fatigue, HRQOL, and family impact, respectively. Linear regressions were used to analyze the designated relationships; path analyses were performed to quantify the mediating effects of HRQOL on fatigue–family impact relationship. Results Although greater fatigue was associated with family impact (p < .05), the association was not significant after accounting for HRQOL. Path analyses indicated the direct effect of fatigue on family impact was not significant (p > .05), whereas physical and emotional functioning significantly mediated the fatigue–family impact relationship (p < .001). Conclusion Fatigue is related to family impact among CSHCNs, acting through the impairment in HRQOL. PMID:23584707
Herr, Raphael M; Li, Jian; Loerbroks, Adrian; Angerer, Peter; Siegrist, Johannes; Fischer, Joachim E
2017-07-01
Ample evidence documented the adverse health effects of work stressors, and recent research has increasingly focused on somatic symptoms which are very common and costly. Prospective evidence is however sparse and yielded mixed findings. Furthermore, there is reason to assume that depression and anxiety might mediate the effects of adverse psychosocial work conditions on somatic symptoms. This study aimed to investigate longitudinal effects of work stressors on somatic symptoms and the potential mediation by anxiety and/or depression. Six year follow-up data from 352 individuals - free of potentially stress-related chronic disease - were utilized. Somatic symptoms were assessed by 19 items of an established list of complaints at baseline and follow-up. The effort-reward-imbalance (ERI) model measured adverse psychosocial work conditions and over-commitment (OC). Linear regressions adjusted for socio-demographics, social status, lifestyle, and baseline symptoms estimated the effects of the ERI ratio, effort, reward, OC, and the ERI ratio×OC interaction on somatic symptoms six years later. Furthermore, single and multiple mediation by anxiety and/or depression was investigated. There was a strong longitudinal effect of the ERI ratio, as well as of its subcomponents, and OC on somatic symptoms (all Bs≥|0.49|; p-values ≤0.004). Moreover, the ERI ratio×OC interaction was significant (p-value=0.047). Multiple mediation analyses revealed especially anxiety to mediate the effect of work stressors on somatic symptoms (Sobel test=0.007). Adverse psychosocial work conditions seem to longitudinally affect somatic symptoms, potentially moderated by OC, and mediated by anxiety. Copyright © 2017 Elsevier Inc. All rights reserved.
Yen, Cheng-Fang; Liu, Tai-Ling; Ko, Chih-Hung; Wu, Yu-Yu; Cheng, Chung-Ping
2014-03-01
The aims of this study were to examine the mediating effect of bullying involvement on the relationships between body mass index (BMI) and mental health problems, including social phobia, depression, suicidality, and low self-esteem among adolescents in Taiwan. The moderation effect of sex on the mediating role of bullying involvement was also examined. Five thousand two hundred and fifty-two students of high schools completed the questionnaires. Victimization and perpetration of passive and active bullying were assessed using the Chinese version of the School Bullying Experience Questionnaire. BMI was calculated from self-reported weight and height measurements. The Social Phobia Inventory, the Mandarin Chinese version of the Center for Epidemiological Studies-Depression Scale, the suicidality-related questionnaire from the epidemiological version of the Kiddie-Schedule for Affective Disorders and Schizophrenia, and the Rosenberg Self-Esteem Scale were applied to assess social phobia, depression, suicidality, and low self-esteem, respectively. The mediating effect of bullying involvement on the associations between increased BMI and mental health problems was examined by the Sobel test. The moderation effect of sex on the mediating role of bullying involvement was tested by the multiple-group structural equation model. Victimization of passive and active bullying and perpetration of passive bullying, but not perpetration of active bullying, had a mediating effect on the relationships between increased BMI and all four mental health problems. Sex did not have a significant moderation effect on the mediating role of bullying involvement. Bullying involvement should be a target of prevention and intervention in developing a strategy to improve mental health among adolescents with increased BMI. Copyright © 2013 Elsevier Ltd. All rights reserved.
Marshall, Paul W M; Schabrun, Siobhan; Knox, Michael F
2017-01-01
Chronic low back pain is a worldwide burden that is not being abated with our current knowledge and treatment of the condition. The fear-avoidance model is used to explain the relationship between pain and disability in patients with chronic low back pain. However there are gaps in empirical support for pathways proposed within this model, and no evidence exists as to whether physical activity moderates these pathways. This was a cross-sectional study of 218 people with chronic low back pain. Multiple mediation analyses were conducted to determine the role of fear, catastrophizing, depression, and anxiety in the relationship between pain and disability. Separate analyses were performed with physical activity as the moderator. Individuals were classified as performing regular structured physical activity if they described on average once per week for > 30-minutes an activity classified at least moderate intensity (≥ 4-6 METs), activity prescribed by an allied health professional for their back pain, leisure time sport or recreation, or self-directed physical activity such as resistance exercise. Fear, catastrophizing, and depression significantly mediated the relationship between pain and disability (p<0.001). However the mediating effect of catastrophizing was conditional upon weekly physical activity. That is, the indirect effect for catastrophizing mediating the relationship between pain and disability was only significant for individuals reporting weekly physical activity (B = 1.31, 95% CI 0.44 to 2.23), compared to individuals reporting no weekly physical activity (B = 0.21, 95% CI -0.50 to 0.97). Catastrophizing also mediated the relationship between pain and fear (B = 0.37, 95% CI 0.15 to 0.62), with higher scores explaining 53% of the total effect of pain on fear. These results support previous findings about the importance of fear and depression as factors that should be targeted in low back pain patients to reduce back pain related disability. We have also extended understanding for the mediating effect of catastrophizing on back pain related disability. Back pain patients engaged with regular physical activity may require counselling with regards to negative pain perceptions.
Marshall, Paul W. M.; Schabrun, Siobhan; Knox, Michael F.
2017-01-01
Background Chronic low back pain is a worldwide burden that is not being abated with our current knowledge and treatment of the condition. The fear-avoidance model is used to explain the relationship between pain and disability in patients with chronic low back pain. However there are gaps in empirical support for pathways proposed within this model, and no evidence exists as to whether physical activity moderates these pathways. Methods This was a cross-sectional study of 218 people with chronic low back pain. Multiple mediation analyses were conducted to determine the role of fear, catastrophizing, depression, and anxiety in the relationship between pain and disability. Separate analyses were performed with physical activity as the moderator. Individuals were classified as performing regular structured physical activity if they described on average once per week for > 30-minutes an activity classified at least moderate intensity (≥ 4–6 METs), activity prescribed by an allied health professional for their back pain, leisure time sport or recreation, or self-directed physical activity such as resistance exercise. Results Fear, catastrophizing, and depression significantly mediated the relationship between pain and disability (p<0.001). However the mediating effect of catastrophizing was conditional upon weekly physical activity. That is, the indirect effect for catastrophizing mediating the relationship between pain and disability was only significant for individuals reporting weekly physical activity (B = 1.31, 95% CI 0.44 to 2.23), compared to individuals reporting no weekly physical activity (B = 0.21, 95% CI -0.50 to 0.97). Catastrophizing also mediated the relationship between pain and fear (B = 0.37, 95% CI 0.15 to 0.62), with higher scores explaining 53% of the total effect of pain on fear. Conclusions These results support previous findings about the importance of fear and depression as factors that should be targeted in low back pain patients to reduce back pain related disability. We have also extended understanding for the mediating effect of catastrophizing on back pain related disability. Back pain patients engaged with regular physical activity may require counselling with regards to negative pain perceptions. PMID:28686644
Pickles, Andrew; Harris, Victoria; Green, Jonathan; Aldred, Catherine; McConachie, Helen; Slonims, Vicky; Le Couteur, Ann; Hudry, Kristelle; Charman, Tony
2015-02-01
The PACT randomised-controlled trial evaluated a parent-mediated communication-focused treatment for children with autism, intended to reduce symptom severity as measured by a modified Autism Diagnostic Observation Schedule-Generic (ADOS-G) algorithm score. The therapy targeted parental behaviour, with no direct interaction between therapist and child. While nonsignificant group differences were found on ADOS-G score, significant group differences were found for both parent and child intermediate outcomes. This study aimed to better understand the mechanism by which the PACT treatment influenced changes in child behaviour though the targeted parent behaviour. Mediation analysis was used to assess the direct and indirect effects of treatment via parent behaviour on child behaviour and via child behaviour on ADOS-G score. Alternative mediation was explored to study whether the treatment effect acted as hypothesised or via another plausible pathway. Mediation models typically assume no unobserved confounding between mediator and outcome and no measurement error in the mediator. We show how to better exploit the information often available within a trial to begin to address these issues, examining scope for instrumental variable and measurement error models. Estimates of mediation changed substantially when account was taken of the confounder effects of the baseline value of the mediator and of measurement error. Our best estimates that accounted for both suggested that the treatment effect on the ADOS-G score was very substantially mediated by parent synchrony and child initiations. The results highlighted the value of repeated measurement of mediators during trials. The theoretical model underlying the PACT treatment was supported. However, the substantial fall-off in treatment effect highlighted both the need for additional data and for additional target behaviours for therapy. © 2014 The Authors. Journal of Child Psychology and Psychiatry. © 2014 Association for Child and Adolescent Mental Health.
Singh, Bhupendra; Shoulson, Rivka; Chatterjee, Anwesha; Ronghe, Amruta; Bhat, Nimee K.; Dim, Daniel C.; Bhat, Hari K.
2014-01-01
The importance of estrogens in the etiology of breast cancer is widely recognized. Estrogen-induced oxidative stress has been implicated in this carcinogenic process. Resveratrol (Res), a natural antioxidant phytoestrogen has chemopreventive effects against a variety of illnesses including cancer. The objective of the present study was to characterize the mechanism(s) of Res-mediated protection against estrogen-induced breast carcinogenesis. Female August Copenhagen Irish rats were treated with 17β-estradiol (E2), Res and Res + E2 for 8 months. Cotreatment of rats with Res and E2 inhibited E2-mediated proliferative changes in mammary tissues and significantly increased tumor latency and reduced E2-induced breast tumor development. Resveratrol treatment alone or in combination with E2 significantly upregulated expression of nuclear factor erythroid 2-related factor 2 (NRF2) in mammary tissues. Expression of NRF2-regulated antioxidant genes NQO1, SOD3 and OGG1 that are involved in protection against oxidative DNA damage was increased in Res- and Res + E2-treated mammary tissues. Resveratrol also prevented E2-mediated inhibition of detoxification genes AOX1 and FMO1. Inhibition of E2-mediated alterations in NRF2 promoter methylation and expression of NRF2 targeting miR-93 after Res treatment indicated Res-mediated epigenetic regulation of NRF2 during E2-induced breast carcinogenesis. Resveratrol treatment also induced apoptosis and inhibited E2-mediated increase in DNA damage in mammary tissues. Increased apoptosis and decreased DNA damage, cell migration, colony and mammosphere formation in Res- and Res + E2-treated MCF-10A cells suggested a protective role of Res against E2-induced mammary carcinogenesis. Small-interfering RNA-mediated silencing of NRF2 inhibited Res-mediated preventive effects on the colony and mammosphere formation. Taken together, these results suggest that Res inhibits E2-induced breast carcinogenesis via induction of NRF2-mediated protective pathways. PMID:24894866
PUMA mediates the anti-cancer effect of osimertinib in colon cancer cells.
Guo, Lingchuan; Huang, Shan; Wang, Xinwei
2017-01-01
Osimertinib, an irreversible EGFR/HER2 inhibitor, has been found to be effective in the cancer cell with EGFR gene mutations in preclinical lung cancer models. However, the effect of osimertinib in colorectal cancer (CRC) cells is unclear. In the present study, we investigated how osimertinib suppresses CRC cells growth and potentiates effects of other chemotherapeutic drugs. We found that p73-mediated osimertinib-induced p53 upregulated modulator of apoptosis (PUMA) expression irrespective of p53 status following PI3K/AKT pathway inhibition in CRC cells. Furthermore, PUMA is required for osimertinib-induced apoptosis. In addition, osimertinib also synergized with 5-FU to induce significant apoptosis via PUMA in CRC cells. These results demonstrated a critical role of PUMA in mediating the anticancer effects of osimertinib and suggest that PUMA induction can be used as an indicator of osimertinib sensitivity.
PUMA mediates the anti-cancer effect of osimertinib in colon cancer cells
Wang, Xinwei
2017-01-01
Osimertinib, an irreversible EGFR/HER2 inhibitor, has been found to be effective in the cancer cell with EGFR gene mutations in preclinical lung cancer models. However, the effect of osimertinib in colorectal cancer (CRC) cells is unclear. In the present study, we investigated how osimertinib suppresses CRC cells growth and potentiates effects of other chemotherapeutic drugs. We found that p73-mediated osimertinib-induced p53 upregulated modulator of apoptosis (PUMA) expression irrespective of p53 status following PI3K/AKT pathway inhibition in CRC cells. Furthermore, PUMA is required for osimertinib-induced apoptosis. In addition, osimertinib also synergized with 5-FU to induce significant apoptosis via PUMA in CRC cells. These results demonstrated a critical role of PUMA in mediating the anticancer effects of osimertinib and suggest that PUMA induction can be used as an indicator of osimertinib sensitivity. PMID:29138581
Eib, Constanze; Bernhard-Oettel, Claudia; Magnusson Hanson, Linda L; Leineweber, Constanze
2018-03-05
Organizational justice perceptions are considered a predictor of health and well-being. To date, empirical evidence about whether organizational justice perceptions predict health or health predicts organizational justice perceptions is mixed. Furthermore, the processes underlying these relationships are largely unknown. In this article, we study whether bidirectional relationships can be explained by 2 different mediation mechanisms. First, based on the allostatic load model, we suggest that the relationships between organizational justice perceptions and different health indicators are mediated through mental preoccupation with work. Second, based on the affective perception and affective reaction assumption, we investigate if the relationships between different health indicators and organizational justice perceptions are mediated by social support at work. Using a large-scale Swedish panel study (N = 3,236), we test the bidirectional mediating relationships between procedural justice perceptions and self-rated health, depressive symptoms, and sickness absence with a cross-lagged design with 3 waves of data. Significant lagged effects from procedural justice to health were found for models predicting depressive symptoms and sickness absence. Mental preoccupation with work was not found to mediate the longitudinal relationship between procedural justice perceptions and indicators of health. Significant lagged effects from health indicators to procedural justice were found for models involving self-rated health, depressive symptoms, and sickness absence. Social support mediated the longitudinal relationships between all 3 health indicators and procedural justice. Results are discussed in light of previous studies and implications for theory and practice are outlined. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Hsu, Kean J; Beard, Courtney; Rifkin, Lara; Dillon, Daniel G; Pizzagalli, Diego A; Björgvinsson, Thröstur
2015-12-01
Deficits in attentional control have been hypothesized to cause rumination, suggesting that the relationships between attentional control and clinical symptoms may be mediated in part by rumination. However, to date, no clinical study has examined these constructs transdiagnostically in a path analysis model. Fifty-one adults presenting for treatment completed measures of self-reported attentional control, rumination, and depression and anxiety symptoms. A bias-corrected path analysis-based approach was employed to test whether indirect (i.e., mediating) effects of rumination were significantly associated with the direct effects of attentional control on depression and anxiety symptoms. Separate models for depression and anxiety symptoms were tested along with reverse models using attentional control as a proposed mediator. The relationship between attentional control and clinical symptomatology (i.e., both depression and anxiety symptoms) was mediated by rumination. Poor attentional control was associated with more rumination and consequently more severe symptoms of depression and anxiety. The reverse relationship (i.e., attentional control mediating the relationship between rumination and depression or anxiety symptoms) was not significant. Study design did not allow testing of temporal precedence for the mediation models. All constructs were assessed via self-report. Attentional control appears to impact depression and anxiety symptoms through rumination. The pathway between poor attentional control and emotion dysregulation via rumination suggests that interventions targeting attentional control may decrease maladaptive ruminative processes, leading to improved emotion regulation and reduced clinical symptomatology. Future studies should examine the stability of this mediational relationship over time (and in the face of targeted interventions). Copyright © 2015 Elsevier B.V. All rights reserved.
Partridge, Stephanie R; McGeechan, Kevin; Bauman, Adrian; Phongsavan, Philayrath; Allman-Farinelli, Margaret
2016-04-02
Explanatory evaluation of interventions for prevention of weight gain is required beyond changes in weight, to determine for whom the intervention works and the underlying mechanisms of change. It was hypothesised that participant characteristics moderate intervention effect on weight change and improved eating and physical activity behaviours during the 3-month program mediate the relationship between intervention and weight. In our randomised controlled trial, young adults at risk of weight gain (n = 250) were assigned either to an intervention group that received a 3-month mHealth (TXT2BFiT) program with 6-month maintenance or to a control group. Data were collected via online self-report surveys. Hypothesised moderators and mediators of the intervention effect on weight were independently assessed in PROCESS macro models for 3 and 9-month weight change. Males (P = 0.01), mid-20s age group (P = 0.04), and higher income earners (P = 0.02) moderated intervention effects on weight change at 3-months and males only at 9-months (P = 0.02). Weight change at 3 (-1.12 kg) and 9-months (-1.38 kg) remained significant when 3-month nutrition and physical activity behaviours were specified as mediators (P <0.01 and P = 0.01 respectively). Indirect paths explained 39% (0.72/1.85 kg) and 40 % (0.92/2.3 kg) of total effect on weight change at 3 and 9-months respectively. Increased vegetable intake by intervention group at 3-months accounted for 19 and 17% and decreased sugar-sweetened beverages accounted for 8 and 13% of indirect weight change effects at 3 and 9-months respectively. TXT2BFiT was effective for both young men and women. Small sustained behavioural changes, including increased vegetable intake and decreased sugar-sweetened beverages consumption significantly mediated the intervention's effects on weight change. Improved eating behaviours and increased physical activity accounted for approximately 40% of the weight change. The trial is registered with the Australian New Zealand Clinical Trials Registry ( ACTRN12612000924853 ).
Janelsins, Michelle C; Peppone, Luke J; Heckler, Charles E; Kesler, Shelli R; Sprod, Lisa K; Atkins, James; Melnik, Marianne; Kamen, Charles; Giguere, Jeffrey; Messino, Michael J; Mohile, Supriya G; Mustian, Karen M
2016-09-01
Background Interventions are needed to alleviate memory difficulty in cancer survivors. We previously showed in a phase III randomized clinical trial that YOCAS©® yoga-a program that consists of breathing exercises, postures, and meditation-significantly improved sleep quality in cancer survivors. This study assessed the effects of YOCAS©® on memory and identified relationships between memory and sleep. Survivors were randomized to standard care (SC) or SC with YOCAS©® . 328 participants who provided data on the memory difficulty item of the MD Anderson Symptom Inventory are included. Sleep quality was measured using the Pittsburgh Sleep Quality Index. General linear modeling (GLM) determined the group effect of YOCAS©® on memory difficulty compared with SC. GLM also determined moderation of baseline memory difficulty on postintervention sleep and vice versa. Path modeling assessed the mediating effects of changes in memory difficulty on YOCAS©® changes in sleep and vice versa. YOCAS©® significantly reduced memory difficulty at postintervention compared with SC (mean change: yoga=-0.60; SC=-0.16; P<.05). Baseline memory difficulty did not moderate the effects of postintervention sleep quality in YOCAS©® compared with SC. Baseline sleep quality did moderate the effects of postintervention memory difficulty in YOCAS©® compared with SC (P<.05). Changes in sleep quality was a significant mediator of reduced memory difficulty in YOCAS©® compared with SC (P<.05); however, changes in memory difficulty did not significantly mediate improved sleep quality in YOCAS©® compared with SC. In this large nationwide trial, YOCAS©® yoga significantly reduced patient-reported memory difficulty in cancer survivors. © The Author(s) 2015.
Wagnsson, Stefan; Lindwall, Magnus; Gustafsson, Henrik
2014-12-01
The purpose of the study was to test longitudinal (2 years across three occasions) associations between sport participation (SP) and self-esteem (SE) across adolescence (10-18 years), addressing the mediating role of perceived sport competence (PSC) from a developmental perspective. Three waves of data were collected from three age cohorts (10-12, 13-15, and 16-18 years) of school-aged youth (N = 1358). The results demonstrate that SP and SE are related across time and that PSC has an important mediating role in this relationship, both from a skill development and a self-enhancement perspective. In the skill development model, the mediating role of PSC was significantly stronger in the youngest cohort whereas the effect of PSC on subsequent SP in the self-enhancement model was significantly stronger in the 13-15 age group compared with the youngest age group.
Herrera, Miguel F; Pantoja, Juan Pablo; Velázquez-Fernández, David; Cabiedes, Javier; Aguilar-Salinas, Carlos; García-García, Eduardo; Rivas, Alfredo; Villeda, Christian; Hernández-Ramírez, Diego F; Dávila, Andrea; Zaraín, Aarón
2010-07-01
To assess the additional effect of sudden visceral fat reduction by omentectomy on metabolic syndrome, acute-phase reactants, and inflammatory mediators in patients with grade III obesity (G-III O) undergoing laparoscopic Roux-en-Y gastric bypass (LRYGB). Twenty-two patients were randomized into two groups, LRYGB alone or with omentectomy. Levels of interleukin-6, C-reactive protein, tumor necrosis factor-alpha, leptin, adiponectin, glucose, total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides, as well as clinical characteristics, were evaluated before surgery and at 1, 3, 6, and 12 months after surgery. Results were compared between groups. Baseline characteristics were comparable in both groups. Mean operative time was significantly higher in the group of patients who underwent omentectomy (P < 0.001). Median weight of the omentum was 795 +/- 341 g. In one patient, a duodenal perforation occurred at the time of omentectomy. BMI, blood pressure, glucose, total cholesterol, LDL, and triglycerides significantly improved in both groups at 1, 3, 6, and 12 months of follow-up when compared with basal values. However, there were no consistent statistically significant differences among the groups in terms of metabolic syndrome components, acute-phase reactants, and inflammatory mediators. Omentectomy does not have an ancillary short-term significant impact on the components of metabolic syndrome and does not induce important changes in the inflammatory mediators in patients undergoing LRYGB. Operative time is more prolonged when omentectomy is performed.
Age at First Childbirth and Hypertension in Postmenopausal Women.
Park, Sangshin
2017-05-01
Whether age at first childbirth has an effect on hypertension incidence is unclear. The objectives of this study were to examine the relationship between age at first childbirth and hypertension and to examine whether degree of obesity, measured as body mass index, mediates age at first childbirth-related hypertension in postmenopausal women. This study analyzed 4779 postmenopausal women data from the Korea National Health and Nutrition Examination Survey 2010 to 2012. Logistic regression analyses were used to investigate relationship between age at first childbirth and hypertension. Mediation analysis was performed to examine the contribution of body mass index to age at first childbirth-related hypertension. Mean of participants' age at first childbirth and current age were 23.8 and 63.4 years, respectively. The prevalence of hypertension was 51.1%. Age at first childbirth was significantly associated with the prevalence of hypertension (odds ratio, 0.963; 95% confidence interval, 0.930-0.998; P =0.036). Women with age at first childbirth ≤19 years had significantly higher risk of hypertension (odds ratio, 1.61; 95% confidence interval, 1.17-2.23; P =0.004) compared with those >19 years. Multivariable-adjusted prevalence of hypertension was significantly lower in women who delivered the first infant at 20 to 24 (45.5%), 25 to 29 (46.1%), and ≥30 (39.9%) years compared with those at ≤19 years (58.4%). Body mass index completely mediated age at first childbirth-hypertension relationship (indirect effect: odds ratio, 0.992; 95% confidence interval, 0.987-0.998; P =0.008). Age at first childbirth was significantly associated with hypertension in postmenopausal women. Body mass index mediated the effects of age at first childbirth on hypertension. © 2017 American Heart Association, Inc.
Hayes, Andrew F; Rockwood, Nicholas J
2017-11-01
There have been numerous treatments in the clinical research literature about various design, analysis, and interpretation considerations when testing hypotheses about mechanisms and contingencies of effects, popularly known as mediation and moderation analysis. In this paper we address the practice of mediation and moderation analysis using linear regression in the pages of Behaviour Research and Therapy and offer some observations and recommendations, debunk some popular myths, describe some new advances, and provide an example of mediation, moderation, and their integration as conditional process analysis using the PROCESS macro for SPSS and SAS. Our goal is to nudge clinical researchers away from historically significant but increasingly old school approaches toward modifications, revisions, and extensions that characterize more modern thinking about the analysis of the mechanisms and contingencies of effects. Copyright © 2016 Elsevier Ltd. All rights reserved.
Alcover, Carlos-María; Martínez-Iñigo, David; Chambel, Maria José
2012-06-01
Working conditions in call/contact centers influence employees' perceptions of their relations with the organization and their attitudes to work. Such perceptions can be analyzed through the psychological contract. The association between the relational/transactional orientation of the psychological contract and intention to quit the organization was examined, as well as the mediating role of affective commitment in employment relations. Data were collected from 973 employees in a cross-sectional survey. Analysis confirmed that there was a statistically significant relation between the orientation of the psychological contract and intention to quit, which was positive for transactionally oriented and negative for relationally oriented contracts. A mediating role for affective commitment was also confirmed, and a full mediating effect was reported for both orientations.
Birchwood, Max; Dunn, Graham; Meaden, Alan; Tarrier, Nicholas; Lewis, Shon; Wykes, Til; Davies, Linda; Michail, Maria; Peters, Emmanuelle
2017-12-05
Acting on harmful command hallucinations is a major clinical concern. Our COMMAND CBT trial approximately halved the rate of harmful compliance (OR = 0.45, 95% CI 0.23-0.88, p = 0.021). The focus of the therapy was a single mechanism, the power dimension of voice appraisal, was also significantly reduced. We hypothesised that voice power differential (between voice and voice hearer) was the mediator of the treatment effect. The trial sample (n = 197) was used. A logistic regression model predicting 18-month compliance was used to identify predictors, and an exploratory principal component analysis (PCA) of baseline variables used as potential predictors (confounders) in their own right. Stata's paramed command used to obtain estimates of the direct, indirect and total effects of treatment. Voice omnipotence was the best predictor although the PCA identified a highly predictive cognitive-affective dimension comprising: voices' power, childhood trauma, depression and self-harm. In the mediation analysis, the indirect effect of treatment was fully explained by its effect on the hypothesised mediator: voice power differential. Voice power and treatment allocation were the best predictors of harmful compliance up to 18 months; post-treatment, voice power differential measured at nine months was the mediator of the effect of treatment on compliance at 18 months.
Sajjadi, H; Jorjoran Shushtari, Z; Mahboubi, S; Rafiey, H; Salimi, Y
2018-04-01
Understanding pathways that influence substance use potential (SUP) can help with effective substance use prevention interventions among adolescents. The aim of the present study is to contribute to a better understanding of the SUP of adolescents by examining the mediating role of social network quality in the SUP of Iranian adolescents. A cross-sectional study. Structural equation modeling was conducted to assess the hypothesized model that social network quality would mediate the association of family socio-economic status, a mental health disorder, and family smoking with addiction potential. The model shows a good fit to the data. Social network quality mediated the effect of family smoking on the SUP for boys. A mental health disorder had a positive significant direct effect on addiction potential for both girls and boys. Social network quality mediates the effect of family smoking on boys' addiction potential in the context of Iran. Educational programs based on local societal ways and cultural norms are recommended to change tobacco smoking behavior among family members. In addition, to prevent subsequent substance use among adolescents, more effort is needed to improve their mental health. Copyright © 2018 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Ahmad, M. F.; Rasi, R. Z.; Zakuan, N.; Hisyamudin, M. N. N.
2015-12-01
In today's highly competitive market, Total Quality Management (TQM) is vital management tool in ensuring a company can success in their business. In order to survive in the global market with intense competition amongst regions and enterprises, the adoption of tools and techniques are essential in improving business performance. There are consistent results between TQM and business performance. However, only few previous studies have examined the mediator effect namely statistical process control (SPC) between TQM and business performance. A mediator is a third variable that changes the association between an independent variable and an outcome variable. This study present research proposed a TQM performance model with mediator effect of SPC with structural equation modelling, which is a more comprehensive model for developing countries, specifically for Malaysia. A questionnaire was prepared and sent to 1500 companies from automotive industry and the related vendors in Malaysia, giving a 21.8 per cent rate. Attempts were made at findings significant impact of mediator between TQM practices and business performance showed that SPC is important tools and techniques in TQM implementation. The result concludes that SPC is partial correlation between and TQM and BP with indirect effect (IE) is 0.25 which can be categorised as high moderator effect.
Hald, Gert Martin; Malamuth, Neil N
2015-01-01
Using a randomly selected community sample of 200 Danish young adult men and women in a randomized experimental design, the study investigated the effects of a personality trait (agreeableness), past pornography consumption, and experimental exposure to non-violent pornography on attitudes supporting violence against women (ASV). We found that lower levels of agreeableness and higher levels of past pornography consumption significantly predicted ASV. In addition, experimental exposure to pornography increased ASV but only among men low in agreeableness. This relationship was found to be significantly mediated by sexual arousal with sexual arousal referring to the subjective assessment of feeling sexually excited, ready for sexual activities, and/or bodily sensations associated with being sexually aroused. In underscoring the importance of individual differences, the results supported the hierarchical confluence model of sexual aggression and the media literature on affective engagement and priming effects.
Ding, Lin; Wang, Dan; Zhou, Miaomiao; Du, Lei; Xu, Jie; Xue, Changhu; Wang, Yuming
2016-07-01
Recent studies have shown that EPA enriched PLs have beneficial effects on lipid metabolism. Our previous study has demonstrated that the anti-obesity and hypolipidemic effects of EPA-PL were superior to DHA-PL. In the present study, we comparatively evaluated the effects of EPA-enriched phosphatidylcholine (EPA-PC) and EPA-enriched phosphatidylserine (EPA-PS) on lipid metabolism in mice. Both 2% dietary EPA-PC and EPA-PS significantly improved serum and hepatic lipid levels in mice. The HDL-c level in mice on EPA-PC diet was significantly higher than the other two groups. The level of DHA in hepatic TG and PL were significantly increased in both EPA-PC and EPA-PS fed groups (98.3 and 117.8%, respectively; p < 0.05). Notably, the proportion of DHA in EPA-PS group was significantly higher than the EPA-PC group. EPA-PC and EPA-PS suppressed hepatic SREBP-1c mediated lipogenesis and activated PPARα mediated fatty acid β-oxidation in the liver. These data are the first to indicate that EPA-PS has beneficial effects on lipid metabolism.
Stress and sleep reactivity: a prospective investigation of the stress-diathesis model of insomnia.
Drake, Christopher L; Pillai, Vivek; Roth, Thomas
2014-08-01
To prospectively assess sleep reactivity as a diathesis of insomnia, and to delineate the interaction between this diathesis and naturalistic stress in the development of insomnia among normal sleepers. Longitudinal. Community-based. 2,316 adults from the Evolution of Pathways to Insomnia Cohort (EPIC) with no history of insomnia or depression (46.8 ± 13.2 y; 60% female). None. Participants reported the number of stressful events they encountered at baseline (Time 1), as well as the level of cognitive intrusion they experienced in response to each stressor. Stressful events (OR = 1.13; P < 0.01) and stress-induced cognitive intrusion (OR = 1.61; P < 0.01) were significant predictors of risk for insomnia one year hence (Time 2). Intrusion mediated the effects of stressful events on risk for insomnia (P < 0.05). Trait sleep reactivity significantly increased risk for insomnia (OR = 1.78; P < 0.01). Further, sleep reactivity moderated the effects of stress-induced intrusion (P < 0.05), such that the risk for insomnia as a function of intrusion was significantly higher in individuals with high sleep reactivity. Trait sleep reactivity also constituted a significant risk for depression (OR = 1.67; P < 0.01) two years later (Time 3). Insomnia at Time 2 significantly mediated this effect (P < 0.05). This study suggests that premorbid sleep reactivity is a significant risk factor for incident insomnia, and that it triggers insomnia by exacerbating the effects of stress-induced intrusion. Sleep reactivity is also a precipitant of depression, as mediated by insomnia. These findings support the stress-diathesis model of insomnia, while highlighting sleep reactivity as an important diathesis. Drake CL, Pillai V, Roth T. Stress and sleep reactivity: a prospective investigation of the stress-diathesis model of insomnia.
Urban, Kimberly R.; Li, Yan-Chun; Gao, Wen-Jun
2013-01-01
Methylphenidate (Ritalin, MPH) is the most commonly prescribed psychoactive drug for children. Used to treat attention-deficit/hyperactivity disorder (ADHD) and for cognitive enhancement in healthy individuals, its cellular mechanisms of action and potential long-term effects are poorly understood. We recently reported that a clinically relevant (1 mg/kg i.p., single injection) dose of MPH significantly decreased neuronal excitability in the juvenile rat prefrontal cortical neurons. Here we further explore the actions of acute treatment with MPH on the level of NMDA receptor subunits and NMDA receptor-mediated short- and long-term synaptic plasticity in the juvenile rat prefrontal cortical neurons. We found that a single dose of MPH treatment (1 mg/kg, intraperitoneal) significantly decreased the surface and total protein levels of NMDA receptor subunits NR1 and NR2B, but not NR2A, in the juvenile prefrontal cortex. In addition, the amplitude, decay time and charge transfer of NMDA receptor-mediated EPSCs were significantly decreased whereas the amplitude and short-term depression of AMPA receptor-mediated EPSCs were significantly increased in the prefrontal neurons. Furthermore, MPH treatment also significantly increased the probability and magnitude of LTP induction, but had only a small effect on LTD induction in juvenile rat prefrontal cortical neurons. Our data thus present a novel mechanism of action of MPH, i.e., changes in glutamatergic receptor-mediated synaptic plasticity following early-life treatment. Furthermore, since a single dosage resulted in significant changes in NMDA receptors, off-label usage by healthy individuals, especially children and adolescents, may result in altered potential for plastic learning. PMID:23333502
Shrestha, Roman; Weikum, Damian; Copenhaver, Michael; Altice, Frederick L
2017-04-01
Prior research has widely recognized neurocognitive impairment (NCI), depression, and alcohol use disorders (AUDs) as important negative predictors of health-related quality of life (HRQoL) among people living with HIV (PLWH). No studies to date, however, have explored how these neuropsychological factors operate together and affect HRQoL. Incarcerated male PLWH (N = 301) meeting criteria for opioid dependence were recruited from Malaysia's largest prison. Standardized scales for NCI, depression, alcohol use disorders (AUDs) and HRQoL were used to conduct a moderated mediation model to explore the extent to which depression mediated the relationship between NCI, HRQoL, and AUDs using an ordinary least squares regression-based path analytic framework. Results showed that increasing levels of NCI (B = -0.1773, p < 0.001) and depression (B = -0.6147, p < 0.001) were negatively associated with HRQoL. The effect of NCI on HRQoL was significantly (Sobel z = -3.5600, p < 0.001) mediated via depression (B = -0.1230, p < 0.001). Furthermore, the conditional indirect effect of NCI on HRQoL via depression for individuals with AUDs was significant (B = -0.9099, p = 0.0087), suggesting a moderated mediation effect. The findings disentangle the complex relationship using a moderated mediation model, demonstrating that increasing levels of NCI, which can be reduced with HIV treatment, negatively influenced HRQoL via depression for individuals with AUDs. This highlights the need for future interventions to target these complex interplay between neuropsychological factors in order to improve HRQoL among PLWH, particularly incarcerated PLWH with AUDs.
Shrestha, Roman; Weikum, Damian; Copenhaver, Michael; Altice, Frederick L.
2017-01-01
Prior research has widely recognized neurocognitive impairment (NCI), depression, and alcohol use disorders (AUDs) as important negative predictors of health-related quality of life (HRQoL) among people living with HIV (PLWH). No studies to date, however, have explored how these neuropsychological factors operate together and affect HRQoL. Incarcerated male PLWH (N=301) meeting criteria for opioid dependence were recruited from Malaysia’s largest prison. Standardized scales for NCI, depression, alcohol use disorders (AUDs) and HRQoL were used to conduct a moderated mediation model to explore the extent to which depression mediated the relationship between NCI, HRQoL, and AUDs using an ordinary least squares regression-based path analytic framework. Results showed that increasing levels of NCI (B = −.1773, p<0.001) and depression (B = −.6147, p<0.001) were negatively associated with HRQoL. The effect of NCI on HRQoL was significantly (Sobel z = −3.5600, p < 0.001) mediated via depression (B = −.1230, p < 0.001). Furthermore, the conditional indirect effect of NCI on HRQoL via depression for individuals with AUDs was significant (B = −.9099, p = .0087), suggesting a moderated mediation effect. The findings disentangle the complex relationship using a moderated mediation model, demonstrating that increasing levels of NCI, which can be reduced with HIV treatment, negatively influenced HRQoL via depression for individuals with AUDs. This highlights the need for future interventions to target these complex interplay between neuropsychological factors in order to improve HRQoL among PLWH, particularly incarcerated PLWH with AUDs. PMID:27544515
Ben, Jehonathan; Paradies, Yin; Priest, Naomi; Parker, Eleanor Jane; Roberts-Thomson, Kaye F; Lawrence, Herenia P; Broughton, John; Jamieson, Lisa M
2014-01-01
We hypothesized that the psychosocial factors perceived stress and sense of personal control mediated the relationship between self-reported racism and experience of toothache. We hypothesized that social support moderated this relationship. Data from 365 pregnant Aboriginal Australian women were used to evaluate experience of toothache, socio-demographic factors, psychosocial factors, general health, risk behaviors, and self-reported racism exposure. Hierarchical logistic regression models estimated odds ratios (ORs) and 95 percent confidence intervals (CIs) for experience of toothache. Perceived stress and sense of personal control were examined as mediators of the association between self-reported racism and experience of toothache. Social support was examined as a moderator. Self-reported racism persisted as a risk indicator for experience of toothache (OR 1.99, 95 percent CI 1.07-3.72) after controlling for age, level of education, and difficulty paying a $100 dental bill. The relationship between self-reported racism and experience of toothache was mediated by sense of control. The direct effect of self-reported racism on experience of toothache became only marginally significant, and the indirect effect was significant (β coefficient=0.04, bias-corrected 95 percent CI 0.004-0.105, 21.2 percent of effect mediated). Stress was insignificant as a mediator. Social support was insignificant as a moderator. The findings indicate that high levels of self-reported racism were associated with experience of toothache and that sense of control, but not perceived stress, mediated the association between self-reported racism and experience of toothache among this sample of pregnant Aboriginal Australian women. Social support did not moderate the association between self-reported racism and experience of toothache. © 2014 American Association of Public Health Dentistry.
Elliott, Jennifer C; Stohl, Malka; Wall, Melanie M; Keyes, Katherine M; Skodol, Andrew E; Eaton, Nicholas R; Shmulewitz, Dvora; Goodwin, Renee D; Grant, Bridget F; Hasin, Deborah S
2016-05-01
Persistent cases of alcohol and nicotine dependence are associated with considerable morbidity and mortality, and are predicted by childhood maltreatment and personality disorders. Our aim was to test whether personality disorders (individually or conjointly) mediate the relationship between childhood maltreatment and the persistence of dependence. Personality disorders, modeled dimensionally, were tested as mediators of the relationship between childhood maltreatment and the 3-year persistence of alcohol and nicotine dependence in participants in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) who had current alcohol and nicotine dependence in their baseline interview. Individual personality disorders were assessed in separate models. Then, those that were significant were examined jointly in multiple mediator models to determine their total and unique effects. A large, nationally representative US survey. Participants ≥ 18 years who completed baseline and 3-year follow-up NESARC interviews who had baseline alcohol dependence (n = 1172; 68% male) or nicotine dependence (n = 4017; 52.9% male). Alcohol Use Disorder and Associated Disabilities Interview Schedule (AUDADIS-IV) measures of childhood maltreatment, personality disorders and alcohol/nicotine dependence. Individual models indicated that many personality disorders mediated the relationship between childhood maltreatment and the 3-year persistence of alcohol and nicotine dependence (each explaining 6-46% of the total effect, Ps < 0.05). In multiple mediator models, borderline and antisocial symptoms remained significant mediators, each explaining 20-37% of the total effect (Ps < 0.01). Personality disorder symptoms (especially borderline and antisocial) help explain the association between childhood maltreatment and persistent alcohol and nicotine dependence. © 2016 Society for the Study of Addiction.
Elliott, Jennifer C.; Stohl, Malka; Wall, Melanie M.; Keyes, Katherine M.; Skodol, Andrew E.; Eaton, Nicholas R.; Shmulewitz, Dvora; Goodwin, Renee D.; Grant, Bridget F.; Hasin, Deborah S.
2015-01-01
Background and Aims Persistent cases of alcohol and nicotine dependence are associated with considerable morbidity and mortality, and are predicted by childhood maltreatment and personality disorders. Our aim was to test whether personality disorders (individually or conjointly) mediate the relationship between childhood maltreatment and the persistence of dependence. Design Personality disorders, modeled dimensionally, were tested as mediators of the relationship between childhood maltreatment and the 3-year persistence of alcohol and nicotine dependence in participants in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) who had current alcohol and nicotine dependence in their baseline interview. Individual personality disorders were assessed in separate models. Then, those that were significant were examined jointly in multiple mediator models to determine their total and unique effects. Setting A large, nationally representative United States survey. Participants Participants ≥18 years who completed baseline and 3-year follow-up NESARC interviews who had baseline alcohol dependence (n=1,172; 68% male) or nicotine dependence (n=4,017; 52.9% male). Measurements Alcohol Use Disorder and Associated Disabilities Interview Schedule (AUDADIS-IV) measures of childhood maltreatment, personality disorders, and alcohol/nicotine dependence. Findings Individual models indicated that many personality disorders mediated the relationship between childhood maltreatment and the 3-year persistence of alcohol and nicotine dependence (each explaining 6%–46% of the total effect, ps<0.05). In multiple mediator models, borderline and antisocial symptoms remained significant mediators, each explaining 20%–37% of the total effect (ps<0.01). Conclusions Personality disorder symptoms (especially borderline and antisocial) help explain the association between childhood maltreatment and persistent alcohol and nicotine dependence. PMID:26714255
Cramp, A G; Brawley, L R
2009-09-01
The objective of the current investigation was to examine if the effects of a group-mediated cognitive behavioural counselling plus exercise intervention were superior to the effects of a standard exercise care condition on postnatal mothers' self-regulatory efficacy (SRE), outcome expectations (OEs) and self-directed physical activity (PA). The design of the study consisted of two intervention conditions; group-mediated cognitive behavioural counselling plus exercise (GMCB) and standard exercise (SE). Each condition consisted of two phases; a 4-week supervised, centre-based intensive exercise training phase followed by a 4-week home-based phase. Participants were 57 postnatal women randomly assigned to conditions (SE: N=31; GMCB: N=26). Measures of SRE and OEs were assessed prior to and following the centre-based aspect of the intervention. Physical activity was measured following the intensive exercise training phase as well as the home-based phase. GMCB participants' SRE and OEs were sustained during the intervention whereas those of SE participants declined. GMCB participants also reported significantly greater time spent engaging in self-directed PA at the conclusion of the intensive and home-based phases. Mediation analysis revealed that SRE partially mediated the relationship between intervention condition and post home-based PA as confirmed by a significant sobel test. These findings suggest that a theory-based GMCB counselling plus exercise intervention is superior to the SE condition in sustaining SRE and OEs, and in promoting greater self-directed PA. SRE partially mediated the relationship between intervention condition and post home-based PA supporting the targeting of that variable for change as part of the intervention.
Nan, Tianxiang; Zhou, Ziyao; Liu, Ming; Yang, Xi; Gao, Yuan; Assaf, Badih A; Lin, Hwaider; Velu, Siddharth; Wang, Xinjun; Luo, Haosu; Chen, Jimmy; Akhtar, Saad; Hu, Edward; Rajiv, Rohit; Krishnan, Kavin; Sreedhar, Shalini; Heiman, Don; Howe, Brandon M; Brown, Gail J; Sun, Nian X
2014-01-14
Strain and charge co-mediated magnetoelectric coupling are expected in ultra-thin ferromagnetic/ferroelectric multiferroic heterostructures, which could lead to significantly enhanced magnetoelectric coupling. It is however challenging to observe the combined strain charge mediated magnetoelectric coupling, and difficult in quantitatively distinguish these two magnetoelectric coupling mechanisms. We demonstrated in this work, the quantification of the coexistence of strain and surface charge mediated magnetoelectric coupling on ultra-thin Ni0.79Fe0.21/PMN-PT interface by using a Ni0.79Fe0.21/Cu/PMN-PT heterostructure with only strain-mediated magnetoelectric coupling as a control. The NiFe/PMN-PT heterostructure exhibited a high voltage induced effective magnetic field change of 375 Oe enhanced by the surface charge at the PMN-PT interface. Without the enhancement of the charge-mediated magnetoelectric effect by inserting a Cu layer at the PMN-PT interface, the electric field modification of effective magnetic field was 202 Oe. By distinguishing the magnetoelectric coupling mechanisms, a pure surface charge modification of magnetism shows a strong correlation to polarization of PMN-PT. A non-volatile effective magnetic field change of 104 Oe was observed at zero electric field originates from the different remnant polarization state of PMN-PT. The strain and charge co-mediated magnetoelectric coupling in ultra-thin magnetic/ferroelectric heterostructures could lead to power efficient and non-volatile magnetoelectric devices with enhanced magnetoelectric coupling.
Streetscape greenery and health: stress, social cohesion and physical activity as mediators.
de Vries, Sjerp; van Dillen, Sonja M E; Groenewegen, Peter P; Spreeuwenberg, Peter
2013-10-01
Several studies have shown a positive relationship between local greenspace availability and residents' health, which may offer opportunities for health improvement. This study focuses on three mechanisms through which greenery might exert its positive effect on health: stress reduction, stimulating physical activity and facilitating social cohesion. Knowledge on mechanisms helps to identify which type of greenspace is most effective in generating health benefits. In eighty neighbourhoods in four Dutch cities data on quantity and quality of streetscape greenery were collected by observations. Data on self-reported health and proposed mediators were obtained for adults by mail questionnaires (N = 1641). Multilevel regression analyses, controlling for socio-demographic characteristics, revealed that both quantity and quality of streetscape greenery were related to perceived general health, acute health-related complaints, and mental health. Relationships were generally stronger for quality than for quantity. Stress and social cohesion were the strongest mediators. Total physical activity was not a mediator. Physical activity that could be undertaken in the public space (green activity) was, but less so than stress and social cohesion. With all three mediators included in the analysis, complete mediation could statistically be proven in five out of six cases. In these analyses the contribution of green activity was often not significant. The possibility that the effect of green activity is mediated by stress and social cohesion, rather than that it has a direct health effect, is discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.
Predictors of self-perceived cultural competence among children's mental health providers.
Keyser, Victoria; Gamst, Glenn; Meyers, Lawrence S; Der-Karabetian, Aghop; Morrow, Gloria
2014-07-01
Based on empirical research and predictions from the Multicultural Assessment-Intervention Process model, the racial attitudes, ethnic identity, and acculturation of a national sample of 371 child mental health service providers were assessed as possible predictors of practitioner self-perceived cultural competence. It was hypothesized that ethnic identity and racial attitudes would each directly affect self-perceived cultural competence and that acculturation and racial attitudes would mediate the effect of ethnic identity. The results indicated that ethnic identity exerted a direct effect on self-perceived cultural competence and that this effect was partially mediated by respondents' racial attitudes; however, acculturation had no significant role as a mediator. The results are discussed within the context of the Multicultural Assessment-Intervention Process model and implications for providing culturally competent services to children.
The Lifetime Effect of Residential School Attendance on Indigenous Health Status
2014-01-01
Objectives. I examined the health impact of lifetime Indian Residential school (IRS) attendance and the mediating influences of socioeconomic status and community adversity on health outcomes in a national sample of Aboriginal peoples in Canada. Methods. In an analysis of data on 13 881 Inuit, Métis, and off-reserve First Nations or North American Indian adults responding to the postcensus 2006 Aboriginal Peoples Survey administered October 2006 to March 2007, I tested the direct effect of IRS attendance on health and indirect effects through socioeconomic and community factors using logistic regression procedures. Results. Negative health status was significantly more likely with IRS attendance than nonattendance. The direct effect of IRS attendance remained significant although it attenuated substantially when adjusting for demographic characteristics, socioeconomic status, and community-level adversities. Community adversity and socioeconomic factors, primarily income, employment status, and educational attainment mediated the effect of IRS on health. Conclusions. Residential school attendance is a significant health determinant in the Indigenous population and is adversely associated with subsequent health status both directly and through the effects of attendance on socioeconomic and community-level risks. PMID:24328622
Pu, Jun; Hou, Hanpo; Ma, Ruiyang; Sang, Jinyan
2017-12-01
In this study, we investigated the relationship between work-family conflict and job burnout as well as the potential mediation/moderation effects of psychological capital. Participants were 357 university teachers who completed a questionnaire packet containing a work-family conflict scale, psychological capital questionnaire, and Maslach Burnout Inventory-General survey. According to the results, work-family conflict and psychological capital were both significantly correlated with job burnout. In addition, psychological capital cannot mediate-but can moderate-the relationship between work-family conflict and job burnout. Taken together, our findings shed light on the psychological capital underlying the association of work-family conflict and job burnout.
Brammer, Whitney A; Lee, Steve S
2013-01-01
Although there is evidence that the promoter polymorphism of the serotonin transporter (5-HTTLPR) gene is associated with attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD), the pathways underlying these associations are largely unknown. Given their theoretical and biological plausibility, we tested whether individual differences in key temperament dimensions (i.e., prosociality, negative emotionality, daring) constituted potential pathways from 5-HTTLPR to ADHD and ODD. Using a well-characterized sample of 194 six to nine-year-old children with and without ADHD, we utilized multiple mediation procedures with bootstrapping to evaluate prosociality, negative emotionality, and daring as independent mediators of 5-HTTLPR with separate parent and teacher ratings of ADHD and ODD. Controlling for ODD, prosociality and negative emotionality significantly mediated the association of 5-HTTLPR and parent-reported ADHD. Similarly, controlling for ADHD, prosociality and negative emotionality each uniquely mediated the association of 5-HTTLPR and parent-reported ODD. For teacher-reported ADHD, prosociality significantly mediated the association of 5-HTTLPR (controlling for ODD) whereas controlling for ODD, negative emotionality significantly mediated the prediction of teacher-reported ODD from 5-HTTLPR. Specifically, the number of 5-HTTLPR long alleles was inversely associated with prosociality and positively associated with negative emotionality; prosociality was inversely associated and negative emotionality was positively associated with ADHD and ODD. We consider the role of temperament in genetically sensitive designs as well as its potential value in the development and delivery of effective interventions.
Noh, Jin-Won; Park, Hyunchun; Kim, Minji; Kwon, Young Dae; Kim, Jin-Seok
2018-01-01
Objective This study investigated the mediation effect of stress between the experience of discrimination and life satisfaction among North Korean refugees who resettled in South Korea. The findings of the current study provide empirical evidence for the need of social interventions to mitigate adverse effects of stress on North Korean refugees who are subject to social discrimination on a daily basis. Methods In this study, we included 500 subjects among 2,138 North Korean refugees who took refuge in South Korea in 2007. The interview started from April 6th 2009 and finished on May 25th 2009. We conducted moderator effect analysis with Path analysis was conducted because we confirm the experience of discrimination was affected by life satisfaction and stress can affected life satisfaction as a moderator. Results The experience of discrimination significantly affects stress and stress significantly affects life satisfaction. However, the experience of discrimination was not directly related to life satisfaction. The more stress the study respondents experienced, the lower the life satisfaction they reported. Conclusion The present finding suggests that the effects of discriminating experiences on the life satisfaction of North Korean refugees in South Korea were mediated by their own perceived stress. PMID:29422925
Ghosh, Arnab; Koestner, Wolfgang; Hapke, Martin; Schlaphoff, Verena; Länger, Florian; Baumann, Rolf; Koenecke, Christian; Cornberg, Markus; Welte, Karl; Blazar, Bruce R.
2009-01-01
Antigen-presenting cells (APCs) of host origin drive graft-versus-leukemia (GVL) effects but can also trigger life-threatening graft-versus-host disease (GVHD) after hematopoietic cell transplantation (HCT) across major histocompatibility complex (MHC) barriers. We show that in vitro priming of donor lymphocytes can circumvent the need of recipient-derived APCs in vivo for mediating robust GVL effects and significantly diminishes the risk of severe GVHD. In vitro, generated and expanded T cells (ETCs) mediate anti-leukemia effects only when primed on recipient-derived APCs. Loading of APCs in vitro with leukemia cell lysate, chimerism status of the recipient, and timing of adoptive transfer after HCT are important factors determining the outcome. Delayed transfer of ETCs resulted in strong GVL effects in leukemia-bearing full chimera (FC) and mixed chimera (MC) recipients, which were comparable with the GVL/GVHD rates observed after the transfer of naive donor lymphocyte infusion (DLI). Upon early transfer, GVL effects were more pronounced with ETCs but at the expense of significant GVHD. The degree of GVHD was most severe in MCs after transfer of ETCs that had been in vitro primed either on nonpulsed recipient-derived APCs or with donor-derived APCs. PMID:19182207
Ghosh, Arnab; Koestner, Wolfgang; Hapke, Martin; Schlaphoff, Verena; Länger, Florian; Baumann, Rolf; Koenecke, Christian; Cornberg, Markus; Welte, Karl; Blazar, Bruce R; Sauer, Martin G
2009-04-30
Antigen-presenting cells (APCs) of host origin drive graft-versus-leukemia (GVL) effects but can also trigger life-threatening graft-versus-host disease (GVHD) after hematopoietic cell transplantation (HCT) across major histocompatibility complex (MHC) barriers. We show that in vitro priming of donor lymphocytes can circumvent the need of recipient-derived APCs in vivo for mediating robust GVL effects and significantly diminishes the risk of severe GVHD. In vitro, generated and expanded T cells (ETCs) mediate anti-leukemia effects only when primed on recipient-derived APCs. Loading of APCs in vitro with leukemia cell lysate, chimerism status of the recipient, and timing of adoptive transfer after HCT are important factors determining the outcome. Delayed transfer of ETCs resulted in strong GVL effects in leukemia-bearing full chimera (FC) and mixed chimera (MC) recipients, which were comparable with the GVL/GVHD rates observed after the transfer of naive donor lymphocyte infusion (DLI). Upon early transfer, GVL effects were more pronounced with ETCs but at the expense of significant GVHD. The degree of GVHD was most severe in MCs after transfer of ETCs that had been in vitro primed either on nonpulsed recipient-derived APCs or with donor-derived APCs.
Huang, Wei; Cane, Matthew C; Mukherjee, Rajarshi; Szatmary, Peter; Zhang, Xiaoying; Elliott, Victoria; Ouyang, Yulin; Chvanov, Michael; Latawiec, Diane; Wen, Li; Booth, David M; Haynes, Andrea C; Petersen, Ole H; Tepikin, Alexei V; Criddle, David N
2017-01-01
Objective Caffeine reduces toxic Ca2+ signals in pancreatic acinar cells via inhibition of inositol 1,4,5-trisphosphate receptor (IP3R)-mediated signalling, but effects of other xanthines have not been evaluated, nor effects of xanthines on experimental acute pancreatitis (AP). We have determined effects of caffeine and its xanthine metabolites on pancreatic acinar IP3R-mediated Ca2+ signalling and experimental AP. Design Isolated pancreatic acinar cells were exposed to secretagogues, uncaged IP3 or toxins that induce AP and effects of xanthines, non-xanthine phosphodiesterase (PDE) inhibitors and cyclic adenosine monophosphate and cyclic guanosine monophosphate (cAMP/cGMP) determined. The intracellular cytosolic calcium concentration ([Ca2+]C), mitochondrial depolarisation and necrosis were assessed by confocal microscopy. Effects of xanthines were evaluated in caerulein-induced AP (CER-AP), taurolithocholic acid 3-sulfate-induced AP (TLCS-AP) or palmitoleic acid plus ethanol-induced AP (fatty acid ethyl ester AP (FAEE-AP)). Serum xanthines were measured by liquid chromatography-mass spectrometry. Results Caffeine, dimethylxanthines and non-xanthine PDE inhibitors blocked IP3-mediated Ca2+ oscillations, while monomethylxanthines had little effect. Caffeine and dimethylxanthines inhibited uncaged IP3-induced Ca2+ rises, toxin-induced Ca2+ release, mitochondrial depolarisation and necrotic cell death pathway activation; cAMP/cGMP did not inhibit toxin-induced Ca2+ rises. Caffeine significantly ameliorated CER-AP with most effect at 25 mg/kg (seven injections hourly); paraxanthine or theophylline did not. Caffeine at 25 mg/kg significantly ameliorated TLCS-AP and FAEE-AP. Mean total serum levels of dimethylxanthines and trimethylxanthines peaked at >2 mM with 25 mg/kg caffeine but at <100 µM with 25 mg/kg paraxanthine or theophylline. Conclusions Caffeine and its dimethylxanthine metabolites reduced pathological IP3R-mediated pancreatic acinar Ca2+ signals but only caffeine ameliorated experimental AP. Caffeine is a suitable starting point for medicinal chemistry. PMID:26642860
Jia, Yingnan; Fu, Hua; Gao, Junling; Dai, Junming; Zheng, Pinpin
2018-04-05
To understand the potential influencing factors on the effectiveness of workplace health promotion interventions and examine whether workplace health culture and physical environment can mediate the relationship between workplace health promotion and intervention effectiveness. A total of 719 participants from 10 Chinese government agencies were recruited for a prospective self-controlled trial. Questionnaires, qualitative interviews, and direct observation were used for the baseline evaluation, process evaluation, and effectiveness evaluation. Based on the results of the need assessment and risk assessment at each workplace, a two-year comprehensive health intervention was conducted by each workplace. Health outcomes including self-rated health (SRH) and mental health were measured at baseline and 24 months. Health culture was measured at 24 months. Physical environment and intervention implementation were measured at 12 months and 24 months. Compared with the baseline, the means of SRH and mental health increased significantly by 0.302 and 2.698, respectively. The SRH scores were different before and after intervention; furthermore, the differences varied by workplace. Health culture mediated the relationship between intervention implementation and intervention effectiveness, including SRH and mental health improvement, but physical environment did not. Physical environment quality was significantly negatively correlated with SRH improvement and mental health improvement. Under the relatively high-quality interventions with scores higher than 4.047 or 4.151 (out of 5), better health culture may led to greater SRH and mental health improvements. Health culture may mediate the relationship between intervention implementation and intervention effectiveness, whereas physical environment does not seem to mediate this relationship. Under relatively high-quality interventions, a better health culture may lead to more positive improvements in SRH and mental health. Future studies will need to examine the physical environment as a moderating effect rather than mediating effect. This study was retrospectively registered in Chinese Clinical Trial Registry. ChiCTR-OOC-16010059 . Date of registration: Dec 1, 2016.
Fasting is a physiological stimulus of vagus-mediated enhancement of nociception in the female rat.
Khasar, S G; Reichling, D B; Green, P G; Isenberg, W M; Levine, J D
2003-01-01
The vagus nerve modulates nociception by a mechanism dependent upon gonadal hormones and the adrenal medulla. In the present study we tested the hypothesis that this modulation is dynamically controlled by physiological stimulation of structures innervated by the subdiaphragmatic vagus. Specifically, food deprivation (fasting) was employed to increase activity in the subdiaphragmatic vagus, and the experiments were performed mainly in female rats because our previous observations suggested that baseline activity in the pathway is lower in females than in males. Consistent with the hypothesis, after a 48-h fast, female rats exhibited increased nociceptive behavior in the formalin test. In contrast, fasting had no effect on formalin-evoked nociceptive behavior in male rats. The fasting-induced effect on nociception appears to be mediated by the vagus nerve since it is prevented by subdiaphragmatic vagotomy. Also similar to the previously characterized vagus-mediated modulation, the effect of fasting in the female is blocked by gonadectomy or adrenal medullectomy, and hormone replacement with 17beta-estradiol in gonadectomized female rats restored the effect of fasting. Decreased glucose metabolism apparently does not play a significant role in the effect of fasting on nociception, since the effect was unchanged when 5% glucose was provided in the drinking water throughout the fasting period. On the other hand, increasing the bulk content of the stomach (without providing nutrients) by infusion of petrolatum significantly attenuated the effect of fasting during the interphase period of the formalin response, suggesting that decreased gut distention, and possibly motility, are important in fasting-induced enhancement of nociception. These results indicate that fasting is a physiological activator of the vagus-mediated pain modulation pathway. This suggests the possibility that, especially in females, natural periodic changes in gut distention and motility may control an ongoing vagus-mediated adjustment in the organism's nociceptive sensitivity.
Effects of ZD7288 on firing pattern of thermosensitive neurons isolated from hypothalamus.
Cai, Chunqing; Meng, Xiaojing; He, Junchu; Wu, Hangyu; Zou, Fei
2012-01-11
The role of the hyperpolarization-activated current (Ih) mediated by HCN channels in temperature sensing by the hypothalamus was addressed. In warm-sensitive neurons (WSNs), exposure to ZD7288, an inhibitor of Ih mediated by hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, decreased their action potential amplitudes and frequencies significantly. By contrast, ZD7288 had little or no effect on temperature-insensitive neurons (TINs). Exposure of WSNs to ZD7288 led to a significant increase in the duration of the inter-spike interval and a reduction of Ih irreversibly. These results suggest that ZD7288 have the contrasting effects on the firing patterns of WSNs versus TINs, which implies HCN channels play a central role in temperature sensing by hypothalamic neurons. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Situated Self-efficacy in Introductory Physics Students
NASA Astrophysics Data System (ADS)
Henderson, Rachel; DeVore, Seth; Michaluk, Lynnette; Stewart, John
2017-01-01
Within the general university environment, students' perceived self-efficacy has been widely studied and findings suggest it plays a role in student success. The current research adapted a self-efficacy survey, from the ``Self-Efficacy for Learning Performance'' subscale of the Motivated Learning Strategies Questionnaire and administered it to the introductory, calculus-based physics classes (N=1005) over the fall 2015 and spring 2016 semesters. This assessment measured students' self-efficacy in domains including the physics class, other science and mathematics classes, and their intended future career. The effect of gender was explored with the only significant gender difference (p < . 001) existing within the physics domain. A hierarchical linear regression analysis indicated that this gender difference was not explained by a student's performance which was measured by test average. However, a mediation analysis showed that students' overall academic self-efficacy, measured by their math and science self-efficacy, acts as a mediator for the effect of test average on self-efficacy towards the physics class domain. This mediation effect was significant for both female (p < . 01) and male students (p < . 001) however, it was more pronounced for male students.
Zou, Jilin
2014-06-01
Prior studies indicate that trait emotional intelligence (EI) is associated negatively with loneliness. However, the mechanisms underlying the relationship are not clear. This study assessed whether both self-esteem and social support mediated the associations between trait EI and loneliness. 469 Chinese undergraduate participants whose age ranged from 18 to 23 years (208 women) were asked to complete four self-report questionnaires, including the Wong Law Emotional Intelligence Scale, the Social and Emotional Loneliness Scale, the Rosenberg Self-esteem Scale, and the Multi-Dimensional Scale of Perceived Social Support. Analyses indicated that self-esteem and social support fully mediated the associations between trait EI and loneliness. Effect contrasts indicated that the specific indirect effect through social support was significantly greater than that through self-esteem. Moreover, a multiple-group analysis indicated that no path differed significantly by sex. These results suggest that social support is more important than self-esteem in the association between trait EI and loneliness. Furthermore, both sexes appear to share the same mechanism underlying this association.
Does Positivity Mediate the Relation of Extraversion and Neuroticism with Subjective Happiness?
Lauriola, Marco; Iani, Luca
2015-01-01
Recent theories suggest an important role of neuroticism, extraversion, attitudes, and global positive orientations as predictors of subjective happiness. We examined whether positivity mediates the hypothesized relations in a community sample of 504 adults between the ages of 20 and 60 years old (females = 50%). A model with significant paths from neuroticism to subjective happiness, from extraversion and neuroticism to positivity, and from positivity to subjective happiness fitted the data (Satorra–Bentler scaled chi-square (38) = 105.91; Comparative Fit Index = .96; Non-Normed Fit Index = .95; Root Mean Square Error of Approximation = .060; 90% confidence interval = .046, .073). The percentage of subjective happiness variance accounted for by personality traits was only about 48%, whereas adding positivity as a mediating factor increased the explained amount of subjective happiness to 78%. The mediation model was invariant by age and gender. The results show that the effect of extraversion on happiness was fully mediated by positivity, whereas the effect of neuroticism was only partially mediated. Implications for happiness studies are also discussed. PMID:25781887
Verbal and Visual Memory Impairments in Bipolar I and II Disorder.
Ha, Tae Hyon; Kim, Ji Sun; Chang, Jae Seung; Oh, Sung Hee; Her, Ju Young; Cho, Hyun Sang; Park, Tae Sung; Shin, Soon Young; Ha, Kyooseob
2012-12-01
To compare verbal and visual memory performances between patients with bipolar I disorder (BD I) and patients with bipolar II disorder (BD II) and to determine whether memory deficits were mediated by impaired organizational strategies. Performances on the Korean-California Verbal Learning Test (K-CVLT) and the Rey-Osterrieth Complex Figure Test (ROCF) in 37 patients with BD I, 46 patients with BD II and 42 healthy subjects were compared. Mediating effects of impaired organization strategies on poor delayed recall was tested by comparing direct and mediated models using multiple regression analysis. Both patients groups recalled fewer words and figure components and showed lower Semantic Clustering compared to controls. Verbal memory impairment was partly mediated by difficulties in Semantic Clustering in both subtypes, whereas the mediating effect of Organization deficit on the visual memory impairment was present only in BD I. In all mediated models, group differences in delayed recall remained significant. Our findings suggest that memory impairment may be one of the fundamental cognitive deficits in bipolar disorders and that executive dysfunctions can exert an additional influence on memory impairments.
Chen, Shih-Chih; Jong, Din; Lai, Min-Tsai
2014-09-01
Numerous types of self-service technologies have prevailed due to innovations in network and information technology. To hospitals, patient intentions to continue to use the e-appointment system are crucial. Previous investigations discussed only the relationships between the technology readiness of users and their continuance intentions, and ignored the most important mediator, relationship quality. This study explored the relationships among technology readiness, relationship quality, and continuance intention. The research results demonstrated that both optimism and innovativeness significantly and positively influenced continuance intention through the mediating effect of relationship quality. However, discomfort and insecurity hid not significantly influence relationship quality or continuance intention. Finally, theoretical contributions, managerial implications and future research directions were discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chuang, Cheng-Hung, E-mail: chchuang@hk.edu.tw; Liu, Chia-Hua; Lu, Ta-Jung
2014-12-15
Alpha-tocopherol ether-linked acetic acid (α-TEA) has been reported to exhibit both anti-tumor and anti-metastatic activities in cell culture and animal studies. However, it is unclear whether α-TEA possesses anti-angiogenic effects. In this study, we investigated the effect of α-TEA on vascular endothelial growth factor (VEGF)-induced angiogenesis and matrix metalloproteinase (MMP) expression both in vitro and ex vivo. We found that the α-TEA inhibited tube formation, invasion, and migration in human umbilical vein endothelial cells (HUVECs) and that such actions were accompanied by reduced expression of MMP-2. α-TEA also inhibited ex vivo angiogenesis, as indicated by chicken egg chorioallantoic membrane assay.more » We further showed that α-TEA attenuated protein expression of VEGF receptor-2 (VEGFR-2)-mediated p38 mitogen-activated protein kinase (p38), phosphorylated p38, and focal adhesion kinase (FAK). Moreover, α-TEA (30 μM) significantly up-regulated protein expression of tissue inhibitors of MMP (TIMP)-2 (by 138%) and the metastasis suppressor gene nm23-H1 (by 54%). These results demonstrate that the anti-angiogenic effect of α-TEA both in vitro and ex vivo and its possible mechanistic action appears to involve the inhibition of MMP-2 level through VEGFR-2-mediated FAK and p38 signaling pathways and through up-regulation of TIMP-2 and nm23-H1 expression. - Graphical abstract: Possible mechanisms of α-TEA on inhibited angiogenesis of human umbilical vein endothelial cells. Brief summary In the present study, we have demonstrated that VEGF-mediated angiogenesis is significantly inhibited by α-TEA, and that this effect involves inhibition of MMP-2 level through VEGFR-2-mediated FAK and p38 signaling pathways related to invasion and migration. - Highlights: • The anti-angiogenic effect and the mechanistic action of α-TEA were investigated. • α-TEA significantly inhibited VEGF-mediated angiogenesis both in vitro and ex vivo. • α-TEA down-regulated MMP-2 via VEGFR-2-mediated FAK and p38 signaling pathways. • α-TEA up-regulated TIMP-2 and nm23-H1 expression in relation to invasion and migration. • Further studies are warranted on the anti-angiogenesis potential of α-TEA.« less
Karimli, Leyla; Ssewamala, Fred M
2015-10-01
This present study tests the proposition that an economic strengthening intervention for families caring for AIDS-orphaned adolescents would positively affect adolescent future orientation and psychosocial outcomes through increased asset accumulation (in this case, by increasing family savings). Using longitudinal data from the cluster-randomized experiment, we ran generalized estimating equation models with robust standard errors clustering on individual observations. To examine whether family savings mediate the effect of the intervention on adolescents' future orientation and psychosocial outcomes, analyses were conducted in three steps: (1) testing the effect of intervention on mediator; (2) testing the effect of mediator on outcomes, controlling for the intervention; and (3) testing the significance of mediating effect using Sobel-Goodman method. Asymmetric confidence intervals for mediated effect were obtained through bootstrapping-to address the assumption of normal distribution. Results indicate that participation in a matched Child Savings Account (CSA) program improved adolescents' future orientation and psychosocial outcomes by reducing hopelessness, enhancing self-concept, and improving adolescents' confidence about their educational plans. However, the positive intervention effect on adolescent future orientation and psychosocial outcomes was not transmitted through saving. In other words, participation in the matched CSA program improved adolescent future orientation and psychosocial outcomes regardless of its impact on reported savings. Further research is necessary to understand exactly how participation in economic strengthening interventions, for example, those that employ matched CSAs, shape adolescent future orientation and psychosocial outcomes: what, if not savings, transmits the treatment effect and how? Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
Karimli, Leyla; Ssewamala, Fred M.
2015-01-01
Purpose This present study tests the proposition that an economic strengthening intervention for families caring for AIDS-orphaned adolescents would positively affect adolescent future orientation and psychosocial outcomes through increased asset-accumulation (in this case, by increasing family savings). Methods Using longitudinal data from the cluster-randomized experiment we ran generalized estimating equation (GEE) models with robust standard errors clustering on individual observations. To examine whether family savings mediate the effect of the intervention on adolescents’ future orientation and psychosocial outcomes, analyses were conducted in three steps: (1) testing the effect of intervention on mediator; (2) testing the effect of mediator on outcomes, controlling for the intervention; and (3) testing the significance of mediating effect using Sobel-Goodman method. Asymmetric confidence intervals for mediated effect were obtained through bootstrapping—to address the assumption of normal distribution. Results Results indicate that participation in a matched Child Savings Account program improved adolescents’ future orientation and psychosocial outcomes by reducing hopelessness, enhancing self-concept, and improving adolescents’ confidence about their educational plans. However, the positive intervention effect on adolescent future orientation and psychosocial outcomes was not transmitted through saving. In other words, participation in the matched Child Savings Account program improved adolescent future orientation and psychosocial outcomes regardless of its impact on reported savings. Conclusions Further research is necessary to understand exactly how participation in economic strengthening interventions, for example, those that employ matched Child Savings Accounts, shape adolescent future orientation and psychosocial outcomes: what, if not savings, transmits the treatment effect and how? PMID:26271162
Shi, Lin-Bo; Xu, Hua-Ping; Wu, Yu-Jie; Li, Xin; Gao, Jin-Yan; Chen, Hong-Bing
2018-06-01
Low levels of endosulfan are known to stimulate mast cells to release allergic mediators, while imidacloprid can inhibit IgE-mediated mast cell degranulation. However, little information about the effects of both pesticides together on mast cell degranulation is available. To measure the effects, IgE-activated mouse bone marrow-derived mast cells (BMMCs) were treated with imidacloprid and endosulfan, individually, and simultaneously at equi-molar concentrations in tenfold steps ranging from 10 -4 to 10 -11 M, followed by measuring several allergy-related parameters expressed in BMMCs: the mediator production and influx of Ca 2+ , the phosphorylation content of NF-κB in the FcεRI signaling pathway. Then, the effects of the mixtures on IgE-induced passive systemic anaphylaxis (PSA) of BALB/c was detectded. This study clearly showed that the application of equi-molar mixtures of both pesticides with 10 -4 -10 -5 M significantly inhibited the IgE-mediated mouse bone marrow-derived mast cells degranulation in vitro and 10 -4 M of them decreased IgE-mediated PSA in vivo, as the application of imidacloprid at the same concentration alone did. Morever endosulfan alone had no remarkable stimulatory effects on any of the factors measured. In conclusion, simultaneous application of equi-molar concentrations of both pesticides generally showed highly similar responses compared to the responses to imidacloprid alone, suggesting that the effects of the mixture could be solely attributed to the effects of imidacloprid. Copyright © 2018 Elsevier Inc. All rights reserved.
The relationship between parent and student religious coping and college alcohol use.
Harrell, Zaje A T; Powell, Kandace
2014-06-01
The present study examined social support and alcohol norms as mediators of the relationship between religious coping and college drinking (e.g., frequency and heavy drinking). The sample consisted of college students (n = 129) and their parents (n = 113). Religious coping (parent and student) was associated with less frequent alcohol use and less heavy drinking. Using a path model to test direct and indirect effects, the mediators were entered simultaneously and allowed to correlate with each other. Alcohol norms mediated the relationship between religious coping and drinking outcomes. Social support was not a significant mediator. Broader protective implications of religious coping are discussed.
Dyall, S C; Mandhair, H K; Fincham, R E A; Kerr, D M; Roche, M; Molina-Holgado, F
2016-08-01
Emerging evidence suggests a complex interplay between the endocannabinoid system, omega-3 fatty acids and the immune system in the promotion of brain self-repair. However, it is unknown if all omega-3 fatty acids elicit similar effects on adult neurogenesis and if such effects are mediated or regulated by interactions with the endocannabinoid system. This study investigated the effects of DHA and EPA on neural stem cell (NSC) fate and the role of the endocannabinoid signalling pathways in these effects. EPA, but not DHA, significantly increased proliferation of NSCs compared to controls, an effect associated with enhanced levels of the endocannabinoid 2-arachidonylglycerol (2-AG) and p-p38 MAPK, effects attenuated by pre-treatment with CB1 (AM251) or CB2 (AM630) receptor antagonists. Furthermore, in NSCs derived from IL-1β deficient mice, EPA significantly decreased proliferation and p-p38 MAPK levels compared to controls, suggesting a key role for IL-1β signalling in the effects observed. Although DHA similarly increased 2-AG levels in wild-type NSCs, there was no concomitant increase in proliferation or p-p38 MAPK activity. In addition, in NSCs from IL-1β deficient mice, DHA significantly increased proliferation without effects on p-P38 MAPK, suggesting effects of DHA are mediated via alternative signalling pathways. These results provide crucial new insights into the divergent effects of EPA and DHA in regulating NSC proliferation and the pathways involved, and highlight the therapeutic potential of their interplay with endocannabinoid signalling in brain repair. Copyright © 2016 Elsevier Ltd. All rights reserved.
Dissociable Genetic Contributions to Error Processing: A Multimodal Neuroimaging Study
Agam, Yigal; Vangel, Mark; Roffman, Joshua L.; Gallagher, Patience J.; Chaponis, Jonathan; Haddad, Stephen; Goff, Donald C.; Greenberg, Jennifer L.; Wilhelm, Sabine; Smoller, Jordan W.; Manoach, Dara S.
2014-01-01
Background Neuroimaging studies reliably identify two markers of error commission: the error-related negativity (ERN), an event-related potential, and functional MRI activation of the dorsal anterior cingulate cortex (dACC). While theorized to reflect the same neural process, recent evidence suggests that the ERN arises from the posterior cingulate cortex not the dACC. Here, we tested the hypothesis that these two error markers also have different genetic mediation. Methods We measured both error markers in a sample of 92 comprised of healthy individuals and those with diagnoses of schizophrenia, obsessive-compulsive disorder or autism spectrum disorder. Participants performed the same task during functional MRI and simultaneously acquired magnetoencephalography and electroencephalography. We examined the mediation of the error markers by two single nucleotide polymorphisms: dopamine D4 receptor (DRD4) C-521T (rs1800955), which has been associated with the ERN and methylenetetrahydrofolate reductase (MTHFR) C677T (rs1801133), which has been associated with error-related dACC activation. We then compared the effects of each polymorphism on the two error markers modeled as a bivariate response. Results We replicated our previous report of a posterior cingulate source of the ERN in healthy participants in the schizophrenia and obsessive-compulsive disorder groups. The effect of genotype on error markers did not differ significantly by diagnostic group. DRD4 C-521T allele load had a significant linear effect on ERN amplitude, but not on dACC activation, and this difference was significant. MTHFR C677T allele load had a significant linear effect on dACC activation but not ERN amplitude, but the difference in effects on the two error markers was not significant. Conclusions DRD4 C-521T, but not MTHFR C677T, had a significant differential effect on two canonical error markers. Together with the anatomical dissociation between the ERN and error-related dACC activation, these findings suggest that these error markers have different neural and genetic mediation. PMID:25010186
Sangawi, Hoshiar; Adams, John; Reissland, Nadja
2016-08-23
Although the importance of parenting styles directly influencing child development is well established, fewer studied have examined whether parenting styles also affect children's behavioural problems indirectly, mediated through children's academic self-concept (ASC). We examined direct and shared effects of parenting styles on behavioural problems of 199 Kurdish primary school children with a mean age of 11 years 7 months (range 11 years 5 months to 12 years 3 months). Questionnaires measured parenting styles (child version of Alabama Parenting Questionnaire), assessed children's ASC (Myself-As-Learner Scale) and identified children's behavioural problems with the Strengths and Difficulties Questionnaire (SDQ). PROCESS analysis was used to perform the mediation analysis. The results revealed that positive and negative parenting composites are indirectly related to children's internalising behaviour problems. In addition, ASC partially mediated the relationship between the negative parenting composite and prosocial behaviour. However, the mediation analysis did not show the expected indirect effect of parenting styles on externalising problems as being mediated via ASC. Hence, we argue that the ASC serves as a significant mediator in the relationship between parenting styles with prosocial behaviour and internalising problems. © 2016 International Union of Psychological Science.
Bhavsar, V H; Dhumal, V R; Kelkar, V V
1981-09-11
Daily administration of electroconvulsive shocks (ECS) to rats for 10 days resulted in enhanced 5-hydroxytryptamine (5-HT), dopamine (DA) and noradrenaline (NA)-mediated behavioural responses. 5-HT and NA-mediated responses were still enhanced after 21 shock-free days. The three types of behavioural responses were also studied in rats given phenytoin sodium, carbamazepine and diazepam every day, alone, or 1 h after ECS administration. Phenytoin did not alter the ECS-induced enhancement of any of the three behaviours. Carbamazepine and diazepam significantly retarded the enhancement in 5-HT and DA-mediated behaviours, although they did not alter the enhancement in NA-mediated behaviour.
Wei, Meifen; Ku, Tsun-Yao; Liao, Kelly Yu-Hsin
2011-04-01
We examined whether perception of university environment mediated the association between minority status stress and college persistence attitudes after controlling for perceived general stress. Participants were 160 Asian American, African American, and Latino students who attended a predominantly White university. Results of a path model analysis showed that university environment was a significant mediator for the association between minority status stress and college persistence attitudes. Additionally, minority status stress was distinct from perceived general stress. Finally, the results from a multiple-group comparison indicated that the magnitude of the mediation effect was invariant across Asian American, African American, and Latino college students, thus supporting the generalizability of the mediation model.
Panchagnula, R; Bansal, T; Varma, M V S; Kaul, C L
2005-12-01
P-Glycoprotein (P-gp) mediated efflux is recognized as a significant biochemical barrier affecting oral absorption for a number of drugs. Various conflicting reports have been published regarding the effects of grapefruit juice (GFJ) on P-gp-mediated drug efflux, in which GFJ has been shown both to inhibit and activate it. Hence, the present study adopted a two-way approach, involving both co-treatment and chronic administration. Bi-directional transport of paclitaxel (PCL) was carried out in the absence and presence of GFJ extract, in rat everted ileum sac. Further, the effect of chronic administration of GFJ to rats was characterized by permeability studies with indinavir (INDI). Co-treatment of GFJ extract at 100% concentration reduced the asymmetric transport of PCL (efflux ratio = 20.8) by increasing absorptive (A --> B) transport by 921% and reducing secretory (B --> A) transport by 41%. Further, GFJ showed a concentration dependent effect on PCL permeability. Imipramine, a passive permeability marker with absorptive permeability of 15.33 +/- 4.26 x 10(-6) cm/s showed no asymmetric transport and also no significant (P < 0.05) change in permeability in the presence of GFJ. Chronic administration of GFJ resulted in a significant decrease in absorptive transport of indinavir, which was even greater than that produced by rifampicin pretreatment. No change in permeability of propranolol, a passive permeability marker, was observed. Further, the decrease in absorptive transport of INDI was reversed by the P-gp inhibitor verapamil. In conclusion, GFJ extract inhibited P-gp-mediated efflux in co-treatment, whereas chronic administration led to increased levels of P-gp expression, thus having a profound effect on intestinal absorption and GFJ-drug interactions in vivo.
Cutaneous body image dissatisfaction and suicidal ideation: mediation by interpersonal sensitivity.
Gupta, Madhulika A; Gupta, Aditya K
2013-07-01
Cutaneous body image (CBI) dissatisfaction, feelings of social exclusion and stigmatization have been associated with increased suicidality in dermatology patients. We examined the relation between CBI dissatisfaction and suicidal ideation in a non-clinical sample, and examined the possible mediating effect of interpersonal sensitivity (IS), a symptom dimension related to self-consciousness, feelings of inferiority and social exclusion. As part of a larger study, 312 community-based participants from London, Ontario, Canada (241 women, 71 men; mean±SD age: 38.4±14.9years) rated their CBI satisfaction, measured with the Cutaneous Body Image Scale (Gupta MA et al., 2004). The Brief Symptom Inventory (BSI) (Derogatis L et al.,1982) was used to measure the constructs of suicidal ideation (4 suicide-related items from the BSI) and IS (Interpersonal Sensitivity subscale of BSI). Assessing mediation using the Baron & Kenny (1986) model, CBI satisfaction had a significant negative effect on suicidal ideation [c=-0.316, t(296)=-5.73, p<0.001] and IS [a=-0.365, t(297)=-6.76, p<0.001]; when CBI satisfaction and IS were considered together, IS had a significant positive effect on suicidal ideation (b=.690, t(295)=15.80, p<.001) while the effect of CBI satisfaction on suicidal ideation was no longer significant [c*=-.063, t(295)=-1.44, ns]. Our findings suggest an inverse relationship between CBI satisfaction and suicidal ideation, which is mediated by IS. This relationship likely falls in a continuum between non-clinical and clinical situations, with suicide risk being greater when individuals experience greater CBI dissatisfaction and social alienation. Copyright © 2013 Elsevier Inc. All rights reserved.
Huang, Chao-Yuan; Hung, Man-Hsin; Shih, Chi-Ting; Hsieh, Feng-Shu; Kuo, Chiung-Wen; Tsai, Ming-Hsien; Chang, Shih-Shin; Hsiao, Yung-Jen; Chen, Li-Ju; Chao, Tzu-I; Chen, Kuen-Feng
2018-06-18
Increasing evidence suggests that SET functions as an oncoprotein and promotes cancer survival and therapeutic resistance. However, whether SET affects radiotherapy (RT)-mediated anti-cancer effects has not yet been explored. Here, we investigated the impact of SET on RT sensitivity in hepatocellular carcinoma (HCC). Using colony and hepatosphere formation assay, we found that RT-induced proliferative inhibition was critically associated with SET expression. Next, we tested a novel SET antagonist, EMQA, in combination with RT. We showed that additive use of EMQA significantly enhanced the effects of RT against HCC in vitro and in vivo. Notably, compared to mice receiving either RT or EMQA alone, the growth of PLC5 xenografted tumor in mice receiving RT plus EMQA was significantly reduced without compromising treatment tolerability. Furthermore, we proved that antagonizing SET to restore PP2A-mediated p-AKT downregulation was responsible for the synergism between EMQA and RT. Our data demonstrate a new oncogenic property of SET, and provide preclinical evidence that combining a SET antagonist and RT may be effective for treatment of HCC. Further investigation is warranted to validate the clinical relevance of this approach. The American Society for Pharmacology and Experimental Therapeutics.
Kudlacz, E M; Logan, D E; Shatzer, S A; Farrell, A M; Baugh, L E
1993-09-07
Tachykinins, in particular neurokinin A and substance P, produce a number of airway effects which may contribute to respiratory diseases such as asthma. We examined the ability of aerosolized substance P, neurokinin A or capsaicin to produce respiratory alterations in conscious guinea pigs using modified whole body plethysmography. Substance P-mediated dyspnea and significant respiratory events were inhibited by the NK1 receptor antagonist, CP-96,345. Neurokinin A-mediated respiratory effects were ablated by the NK2 receptor antagonists: MEN 10207, MDL 29,913 and SR 48,968, the latter being the most potent. The peptide-based antagonist, MEN 10207, produced respiratory effects itself suggesting partial agonist activity. The cyclic hexapeptide, MDL 29,913, relaxed airway smooth muscle via mechanisms other than tachykinin antagonism. NK2 but not NK1 receptor antagonists were able to delay the onset of capsaicin-induced dyspnea, although alone they did not usually (in approximately 10% of the animals) eliminate the response. However, when NK2 receptor antagonists were combined with CP-96,345, the incidence of dyspnea induced by capsaicin decreased significantly (40%) suggesting that both tachykinins contribute to dyspnea in this system.
Moskowitz, Amanda; Stein, Judith A; Lightfoot, Marguerita
2013-07-01
Runaway and homeless youth often have a constellation of background behavioral, emotional, and familial problems that contribute to stress and maladaptive behaviors, which, in turn, can lead to self-harming and suicidal behaviors. The current study examined the roles of stress and maladaptive behaviors as mediators between demographic and psychosocial background characteristics and self-injurious outcomes through the lens of the stress process paradigm. The model was tested in a sample of runaway and homeless youth from Los Angeles County (N = 474, age 12-24, 41 % female, 17 % White, 32.5 % African American, 21.5 % Hispanic/Latino). Background variables (gender, age, sexual minority status, parental drug use history, and emotional distress) predicted hypothesized mediators of maladaptive behaviors and recent stress. In turn, it was hypothesized that the mediators would predict self-harming behaviors and suicide attempts in the last 3 months. Females and LGBT (lesbian, gay, bisexual, transgender) youth were more likely to have self-harmed and attempted suicide; younger participants reported more self-harming. The mediating constructs were associated more highly with self-harming than suicide attempts bivariately, although differences were modest. Maladaptive behaviors and recent stress were significant predictors of self-harm, whereas only recent stress was a significant predictor of suicide attempts. All background factors were significant predictors of recent stress. Older age, a history of parental drug use, and greater emotional distress predicted problem drug use. Males, younger participants, and participants with emotional distress reported more delinquent behaviors. Significant indirect effects on self-harming behaviors were mediated through stress and maladaptive behaviors. The hypothesized paradigm was useful in explaining the associations among background factors and self-injurious outcomes and the influence of mediating factors on these associations.
The role of anger and ongoing stressors in mental health following a natural disaster.
Forbes, David; Alkemade, Nathan; Waters, Elizabeth; Gibbs, Lisa; Gallagher, Colin; Pattison, Phillipa; Lusher, Dean; MacDougall, Colin; Harms, Louise; Block, Karen; Snowdon, Elyse; Kellet, Connie; Sinnott, Vikki; Ireton, Greg; Richardson, John; Bryant, Richard A
2015-08-01
Research has established the mental health sequelae following disaster, with studies now focused on understanding factors that mediate these outcomes. This study focused on anger, alcohol, subsequent life stressors and traumatic events as mediators in the development of mental health disorders following the 2009 Black Saturday Bushfires, Australia's worst natural disaster in over 100 years. This study examined data from 1017 (M = 404, F = 613) adult residents across 25 communities differentially affected by the fires and participating in the Beyond Bushfires research study. Data included measures of fire exposure, posttraumatic stress disorder, depression, alcohol abuse, anger and subsequent major life stressors and traumatic events. Structural equation modeling assessed the influence of factors mediating the effects of fire exposure on mental health outcomes. Three mediation models were tested. The final model recorded excellent fit and observed a direct relationship between disaster exposure and mental health outcomes (b = .192, p < .001) and mediating relationships via Anger (b = .102, p < .001) and Major Life Stressors (b = .128, p < .001). Each gender was compared with multiple group analyses and while the mediation relationships were still significant for both genders, the direct relationship between exposure and outcome was no longer significant for men (p = .069), but remained significant (b = .234, p < .001) for women. Importantly, anger and major life stressors mediate the relationship between disaster exposure and development of mental health problems. The findings have significant implications for the assessment of anger post disaster, the provision of targeted anger-focused interventions and delivery of government and community assistance and support in addressing ongoing stressors in the post-disaster context to minimize subsequent mental health consequences. © The Royal Australian and New Zealand College of Psychiatrists 2015.
Lloyd, Adam B; Lubans, David R; Plotnikoff, Ronald C; Morgan, Philip J
2015-09-01
This study examined potential parenting-related mediators of children's physical activity and dietary behavior change in the Healthy Dads, Healthy Kids (HDHK) community program. A randomized controlled trial was conducted with 45 overweight/obese (mean [SD] age = 39.8 [5.4] years; BMI = 32.4 [3.8]) fathers and their children (n = 77; 58% boys; mean [SD] age = 7.7 [2.5] years). Families were randomized to either the HDHK program or wait-list control group. The program involved 7 sessions. Fathers and their children were assessed at baseline and at 14 weeks for physical activity (pedometery) and core food intake (Questionnaire). Fathers' lifestyle-related parenting practices included; self-efficacy, beliefs, modeling, logistic support, rules, cophysical activity, shared mealtime frequency and intentions. Significant intervention effects were found for cophysical activity and modeling physical activity. Cophysical activity mediated children's physical activity in the intervention ('mediated effect,' AB = 653, 95% CI = 4-2050) and was responsible for 59.5% of the intervention effect. Fathers' beliefs mediated children's percent energy from core foods (AB = 1.51, 95% CI = 0.05-5.55) and accounted for 72.9% of the intervention effect. Participation in the HDHK program positively impacted on fathers' cophysical activity with their child and beliefs about healthy eating which mediated changes in children's diet and physical activity behaviors.
McHugh Power, J E; Lawlor, B A; Kee, F
2017-06-01
We supplement existing findings on a link between social support and cognitive function in later life by considering the role of personality as an antecedent to both, and of social support as a mediator of the link between personality and cognitive function. An observational cohort study. We evaluated social support using the Lubben Social Network Scale, across 624 adults aged over 60 years, and investigated this measure as a mediator of the relationships between extraversion and neuroticism at baseline 2007-2009, and cognitive function at follow-up, 2 years later. A half-longitudinal mediation design, within a structural equation modelling framework, was used. There was a direct effect of extraversion, such that lower levels were related to higher scores of cognitive function. There was no significant direct effect of neuroticism on cognitive function at follow-up. Social support partially mediated the paths between both extraversion and neuroticism and cognitive function at follow-up. Decomposing the mediation effects by using social support subscales (measuring support from friends, relatives and neighbours) showed meaningful indirect effects for both predictors. Results suggest that social support may offer a target for interventions for cognitively at-risk older adults and add to the existing empirical evidence describing the link between personality and cognitive function. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
Is cognitive adaptation training (CAT) compensatory, restorative, or both?
Fredrick, Megan M; Mintz, Jim; Roberts, David L; Maples, Natalie J; Sarkar, Sonali; Li, Xueying; Velligan, Dawn I
2015-08-01
Cognitive adaptation training (CAT) is a psychosocial treatment incorporating environmental supports including signs, checklists to bypass the cognitive deficits of schizophrenia. Our objective was to examine the association between CAT, functional outcomes, and cognitive test performance (cognition). The two research questions were as follows: 1) Does cognition mediate the effect of CAT intervention on functional outcome? 2) Does CAT impact cognitive test performance? A total of 120 participants with schizophrenia were randomized to one of three treatments: 1) CAT (weekly for 9months; monthly thereafter), 2) generic environmental supports (given to participants on clinic visits to promote adaptive behavior), or 3) treatment as usual (TAU). Assessments of cognition and functional outcome were conducted at baseline, 9 and 24months. Mediation analyses and mixed effects regression were conducted. Mediation analyses revealed that during the initial 9months, the direct path from treatment group to functional outcome on the primary measure was positive and highly significant. CAT significantly improved functional outcome compared to the other treatments. However, paths involving cognition were negligible. There was no evidence that cognition mediated improvement in functional outcomes. At 24months, cognition improved more in CAT compared to other treatment groups. The test for cognition mediating improvement in functional outcomes was not significant at this time point. However, improvement in functional outcome led to better performance on cognitive testing. We concluded that improvement in cognition is not a necessary condition for improvement in functional outcome and that greater engagement in functional behavior has a positive impact on cognition. Copyright © 2015 Elsevier B.V. All rights reserved.
Ko, Linda K.; Turner-McGrievy, Gabrielle; Campbell, Marci K.
2016-01-01
Podcasting is an emerging technology, and previous interventions have shown promising results using theory-based podcast for weight loss among overweight and obese individuals. This study investigated whether constructs of social cognitive theory and information processing theories (IPTs) mediate the effect of a podcast intervention on weight loss among overweight individuals. Data are from Pounds off Digitally, a study testing the efficacy of two weight loss podcast interventions (control podcast and theory-based podcast). Path models were constructed (n = 66). The IPTs—elaboration likelihood model, information control theory, and cognitive load theory—mediated the effect of a theory-based podcast on weight loss. The intervention was significantly associated with all IPTs. Information control theory and cognitive load theory were related to elaboration, and elaboration was associated with weight loss. Social cognitive theory constructs did not mediate weight loss. Future podcast interventions grounded in theory may be effective in promoting weight loss. PMID:24082027
Method of making ionic liquid mediated sol-gel sorbents
Malik, Abdul; Shearrow, Anne M.
2017-01-31
Ionic liquid (IL)-mediated sol-gel hybrid organic-inorganic materials present enormous potential for effective use in analytical microextraction. One obstacle to materializing this prospect arises from high viscosity of ILs significantly slowing down sol-gel reactions. A method was developed which provides phosphonium-based, pyridinium-based, and imidazolium-based IL-mediated advanced sol-gel organic-inorganic hybrid materials for capillary microextraction. Scanning electron microscopy results demonstrate that ILs can serve as porogenic agents in sol-gel reactions. IL-mediated sol-gel coatings prepared with silanol-terminated polymers provided up to 28 times higher extractions compared to analogous sol-gel coatings prepared without any IL in the sol solution. This study shows that IL-generated porous morphology alone is not enough to provide effective extraction media: careful choice of the organic polymer and the precursor with close sol-gel reactivity must be made to ensure effective chemical bonding of the organic polymer to the created sol-gel material to be able to provide the desired sorbent characteristics.
Gaylord-Harden, Noni K; So, Suzanna; Bai, Grace J; Tolan, Patrick H
2017-01-01
The current study examined pathways in a model of desensitization, the Pathologic Adaptation Model, in adolescent males of color. Specifically, the current study examined depressive symptoms and deviant beliefs as mediators of the association between community violence exposure and subsequent violent behavior. The current study included 250 African-American (67%) and Latino (33%) male adolescents (T1 mean age = 15.32) from the Chicago Youth Development Study. Consistent with the Pathologic Adaptation Model, results demonstrated that depressive symptoms mediated the association between the quadratic violence exposure term in middle adolescence and violent behaviors in late adolescence, but the direction of the mediation effect was dependent upon the levels of violence exposure in middle adolescence. However, deviant beliefs were not found to be a significant mediator. Emotional desensitization effects may increase the likelihood of violence perpetration in adolescent males exposed to community violence, and the implications for future research and intervention efforts are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Lai, Catie CW; Ma, Cecilia MS
2016-01-01
While literature has displayed a link between psychological well-being (i.e. depression, hopelessness, and life satisfaction) and health-risk behaviors (i.e. smoking, drinking, suicide, and physical inactivity), the mechanisms underlying this relationship have received little empirical attention. This study examines the mediation effects of social support (from family, friends, and significant others) that accounted for the link. Participants were 2023 university students (47.7% male). Structural equation modeling showed partial mediation effect of social support between psychological well-being and health-risk behaviors. In particular, social support from family and friends jointly mediated about 80 percent of the effect of life satisfaction and hopelessness on drinking. These results offered novel evidence that helps improve theorizing the mechanisms of the relationship between psychological well-being and health-risk behaviors. They also highlighted the potential benefits of social support for university students to help them stay healthy. The implications of these results are discussed. PMID:28070409
Does understanding relational terminology mediate effects of intervention on compare word problems?
Schumacher, Robin F; Fuchs, Lynn S
2012-04-01
The purpose of this study was to assess whether understanding relational terminology (i.e., more, less, and fewer) mediates the effects of intervention on compare word problems. Second-grade classrooms (N=31) were randomly assigned to one of three conditions: researcher-designed word-problem intervention, researcher-designed calculation intervention, or business-as-usual (teacher-designed) control. Students in word-problem intervention classrooms received instruction on the compare problem type, which included a focus on understanding relational terminology within compare word problems. Analyses, which accounted for variance associated with classroom clustering, indicated that (a) compared with the calculation intervention and business-as-usual conditions, word-problem intervention significantly increased performance on all three subtypes of compare problems and on understanding relational terminology, and (b) the intervention effect was fully mediated by students' understanding of relational terminology for one subtype of compare problems and partially mediated by students' understanding of relational terminology for the other two subtypes. Copyright © 2011 Elsevier Inc. All rights reserved.
Aarons, Gregory A.; Sawitzky, Angelina C.
2006-01-01
Staff turnover in mental health service organizations is an ongoing problem with implications for staff morale, productivity, organizational effectiveness, and implementation of innovation. Recent studies in public sector services have examined the impact of organizational culture and climate on work attitudes (i.e., job satisfaction and organizational commitment) and, ultimately, staff turnover. However, mediational models of the impact of culture and climate on work attitudes have not been examined. The present study examined full and partial mediation models of the effects of culture and climate on work attitudes and the subsequent impact of work attitudes on staff turnover. Multilevel structural equation models supported a partial mediation model in which organizational culture had both direct influence on work attitudes and indirect influence through organizational climate. Work attitudes significantly predicted one-year staff turnover rates. These findings support the contention that both culture and climate impact work attitudes and subsequent staff turnover. PMID:16544205
Gaylord-Harden, Noni K.; So, Suzanna; Bai, Grace J.; Tolan, Patrick H.
2016-01-01
Objective The current study examined pathways in a model of desensitization, the Pathologic Adaptation Model, in adolescent males of color. Specifically, the current study examined depressive symptoms and deviant beliefs as mediators of the association between community violence exposure and subsequent violent behavior. Method The current study included 250 African American (67%) and Latino (33%) male adolescents (T1 mean age = 15.32) from the Chicago Youth Development Study. Results Consistent with the Pathologic Adaptation Model, results demonstrated that depressive symptoms mediated the association between the quadratic violence exposure term in middle adolescence and violent behaviors in late adolescence, but the direction of the mediation effect was dependent upon the levels of violence exposure in middle adolescence. However, deviant beliefs were not found to be a significant mediator. Conclusion Emotional desensitization effects may increase the likelihood of violence perpetration in adolescent males exposed to community violence, and the implications for future research and intervention efforts are discussed. PMID:27977283
Aarons, Gregory A; Sawitzky, Angelina C
2006-05-01
Staff turnover in mental health service organizations is an ongoing problem with implications for staff morale, productivity, organizational effectiveness, and implementation of innovation. Recent studies in public sector services have examined the impact of organizational culture and climate on work attitudes (i.e., job satisfaction and organizational commitment) and, ultimately, staff turnover. However, mediational models of the impact of culture and climate on work attitudes have not been examined. The present study examined full and partial mediation models of the effects of culture and climate on work attitudes and the subsequent impact of work attitudes on staff turnover. Multilevel structural equation models supported a partial mediation model in which organizational culture had both direct influence on work attitudes and indirect influence through organizational climate. Work attitudes significantly predicted one-year staff turnover rates. These findings support the contention that both culture and climate impact work attitudes and subsequent staff turnover.
Portal, Shawn; Zadik, Zvi; Rabinowitz, Jonathan; Pilz-Burstein, Ruty; Adler-Portal, Dana; Meckel, Yoav; Cooper, Dan M; Eliakim, Alon; Nemet, Dan
2011-09-01
The use of ergogenic nutritional supplements is becoming inseparable from competitive sports. β-Hydroxy-β-Methylbutyric acid (HMB) has recently been suggested to promote fat-free mass (FFM) and strength gains during resistance training in adults. In this prospective randomized, double-blind, placebo-controlled study, we studied the effect of HMB (3 g/day) supplementation on body composition, muscle strength, anaerobic and aerobic capacity, anabolic/catabolic hormones and inflammatory mediators in elite, national team level adolescent volleyball players (13.5-18 years, 14 males, 14 females, Tanner stage 4-5) during the first 7 weeks of the training season. HMB led to a significant greater increase in FFM by skinfold thickness (56.4 ± 10.2 to 56.3 ± 8.6 vs. 59.3 ± 11.3 to 61.6 ± 11.3 kg in the control and HMB group, respectively, p < 0.001). HMB led to a significant greater increase in both dominant and non-dominant knee flexion isokinetic force/FFM, measured at fast (180°/sec) and slow (60°/sec) angle speeds, but had no significant effect on knee extension and elbow flexion and extension. HMB led to a significant greater increase in peak and mean anaerobic power determined by the Wingate anaerobic test (peak power: 15.5 ± 1.6 to 16.2 ± 1.2 vs. 15.4 ± 1.6 to 17.2 ± 1.2 watts/FFM, mean power: 10.6 ± 0.9 to 10.8 ± 1.1 vs. 10.7 ± 0.8 to 11.8 ± 1.0 watts/FFM in control and HMB group, respectively, p < 0.01), with no effect on fatigue index. HMB had no significant effect on aerobic fitness or on anabolic (growth hormone, IGF-I, testosterone), catabolic (cortisol) and inflammatory mediators (IL-6 and IL-1 receptor antagonist). HMB supplementation was associated with greater increases in muscle mass, muscle strength and anaerobic properties with no effect on aerobic capacity suggesting some advantage for its use in elite adolescent volleyball players during the initial phases of the training season. These effects were not accompanied by hormonal and inflammatory mediator changes.
β-Agonist-mediated Relaxation of Airway Smooth Muscle Is Protein Kinase A-dependent*
Morgan, Sarah J.; Deshpande, Deepak A.; Tiegs, Brian C.; Misior, Anna M.; Yan, Huandong; Hershfeld, Alena V.; Rich, Thomas C.; Panettieri, Reynold A.; An, Steven S.; Penn, Raymond B.
2014-01-01
Inhaled β-agonists are effective at reversing bronchoconstriction in asthma, but the mechanism by which they exert this effect is unclear and controversial. PKA is the historically accepted effector, although this assumption is made on the basis of associative and not direct evidence. Recent studies have asserted that exchange protein activated by cAMP (Epac), not PKA, mediates the relaxation of airway smooth muscle (ASM) observed with β-agonist treatment. This study aims to clarify the role of PKA in the prorelaxant effects of β-agonists on ASM. Inhibition of PKA activity via expression of the PKI and RevAB peptides results in increased β-agonist-mediated cAMP release, abolishes the inhibitory effect of isoproterenol on histamine-induced intracellular calcium flux, and significantly attenuates histamine-stimulated MLC-20 phosphorylation. Analyses of ASM cell and tissue contraction demonstrate that PKA inhibition eliminates most, if not all, β-agonist-mediated relaxation of contracted smooth muscle. Conversely, Epac knockdown had no effect on the regulation of contraction or procontractile signaling by isoproterenol. These findings suggest that PKA, not Epac, is the predominant and physiologically relevant effector through which β-agonists exert their relaxant effects. PMID:24973219
Canada, Andrea L; Murphy, Patricia E; Fitchett, George; Stein, Kevin
2016-02-01
Prior research on spirituality in cancer survivors has often failed to distinguish the specific contributions of faith, meaning, and peace, dimensions of spiritual well-being, to quality of life (QoL), and has misinterpreted mediation analyses with these indices. We hypothesized a model in which faith would have a significant indirect effect on survivors' functional QoL, mediated through meaning and/or peace. Data were from the American Cancer Society's Study of Cancer Survivors-II (N = 8405). Mediation analyses were conducted with the Functional Assessment of Chronic Illness Therapy-Spiritual Well-being Scale (FACIT-Sp) predicting the mental component summary (i.e., mental functioning) as well as the physical component summary (i.e., physical functioning) of the SF-36. The indirect effect of faith through meaning on mental functioning, 0.4303 (95 % CI, 0.3988, 0.4649), and the indirect effect of faith through meaning and peace on physical functioning, 0.1769 (95 % CI, 0.1505, 0.2045), were significant. The study findings suggest that faith makes a significant contribution to cancer survivors' functional QoL. Should future longitudinal research replicate these findings, investigators may need to reconsider the role of faith in oncology QoL studies.
Inhibitory effect of mast cell-mediated immediate-type allergic reactions in rats by spirulina.
Kim, H M; Lee, E H; Cho, H H; Moon, Y H
1998-04-01
We investigated the effect of spirulina on mast cell-mediated immediate-type allergic reactions. Spirulina dose-dependently inhibited the systemic allergic reaction induced by compound 48/80 in rats. Spirulina inhibited compound 48/80-induced allergic reaction 100% with doses of 100-1000 microg/g body weight, i.p. Spirulina (10-1000 microg/g body weight, i.p.) also significantly inhibited local allergic reaction activated by anti-dinitrophenyl (DNP) IgE. When rats were pretreated with spirulina at a concentration ranging from 0.01 to 1000 microg/g body weight, i.p., the serum histamine levels were reduced in a dose-dependent manner. Spirulina (0.001 to 10 microg/mL) dose-dependently inhibited histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. The level of cyclic AMP in RPMC, when spirulina (10 microg/mL) was added, transiently and significantly increased about 70-fold at 10 sec compared with that of control cells. Moreover, spirulina (10 microg/mL) had a significant inhibitory effect on anti-DNP IgE-induced tumor necrosis factor-alpha production. These results indicate that spirulina inhibits mast cell-mediated immediate-type allergic reactions in vivo and in vitro.
Wang, Shan Huei
2017-08-02
Web-based medical service (WBMS), a cooperative relationship between medical service and Internet technology, has been called one of the most innovative services of the 21st century. However, its business promotion and implementation in the medical industry have neither been expected nor executed. Few studies have explored this phenomenon from the viewpoint of inexperienced patients. The primary goal of this study was to explore whether technology attractiveness, medical creditability, and diversified medical information sources could increase users' behavior intention. This study explored the effectiveness of web-based medical service by using three situations to manipulate sources of medical information. A total of 150 questionnaires were collected from people who had never used WBMS before. Hierarchical regression was used to examine the mediation and moderated-mediation effects. Perceived ease of use (P=.002) and perceived usefulness (P=.001) significantly enhance behavior intentions. Medical credibility is a mediator (P=.03), but the relationship does not significantly differ under diverse manipulative information channels (P=.39). Medical credibility could explain the extra variation between technology attractiveness and behavior intention, but not significant under different moderating effect of medical information sources. ©Shan Huei Wang. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 02.08.2017.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peterson, J.D.; Peterson, V.A.; Mendonca, M.T.
Coal combustion residues (CCRs) are documented to negatively impact oral morphology, growth, and development in larval amphibians. It is currently unclear what physiological mechanisms may mediate these effects. Corticosterone, a glucocorticoid hormone, is a likely mediator because when administered exogenously it, like CCRs, also negatively influences oral morphology, growth, and development in larval amphibians. In an attempt to identify if corticosterone mediates these effects, we raised larval Southern Leopard Frogs, Rana sphenocephala, on either sand or CCR substrate and documented effects of sediment type on whole body corticosterone, oral morphology, and time to and mass at key metamorphic stages. Coalmore » combustion residue treated tadpoles contained significantly more corticosterone than controls throughout metamorphosis. However, significantly more oral abnormalities occurred early in metamorphosis when differences in corticosterone levels between treatments were minimal. Overall, CCR-treated tadpoles took significantly more time to transition between key stages and gained less mass between stages than controls, but these differences between treatments decreased during later stages when corticosterone differences between treatments were greatest. Our results suggest endogenous increase in corticosterone content and its influence on oral morphology, growth and development is more complex than previously thought.« less
Michels, Nathalie; Vynckier, Lisa; Moreno, Luis A; Beghin, Laurent; de la O, Alex; Forsner, Maria; Gonzalez-Gross, Marcela; Huybrechts, Inge; Iguacel, Isabel; Kafatos, Antonio; Kersting, Mathilde; Leclercq, Catherine; Manios, Yannis; Marcos, Ascension; Molnar, Denes; Sjöström, Michael; Widhalm, Kurt; De Henauw, Stefaan
2018-04-01
To examine the underlying reasons for the positive relation between socio-economic status (SES) and the diet quality of adolescents. In 2081 adolescents (12.5-17.5 years) of the European HELENA study, a continuous variable on diet quality via 2-day 24-h recalls was available. SES was reflected by parental education, parental occupation and family affluence. Mediation by several psychosocial determinants was tested: self-efficacy, availability at school and home, social support, barriers, benefits, awareness and some self-reported influencers (parents, school, taste, health, friends, food readily available, easy preparation, hunger, price and habits). Multiple mediation analyses were adjusted for age, sex and country. The availability of soft drinks and fruit at home, social support, parental influence, barriers, price influence, taste influence, health influence and food being readily available were significant mediators. The multiple mediation indirect effect accounted for 23-64% of the total effect. Both occupation and education and both maternal and paternal factors could be explained by the mediation. The unavailability of soft drinks was the strongest mediator (17-44% of the total effect). Up to 64% of the positive relation between SES and the diet quality in adolescence could be explained by several healthy eating determinants. Focusing on these factors in low-SES populations can minimize social inequalities in diet and health by improving the diet of these specific adolescents.
Liu, Hsin-Yun; Yang, Ching-Tzu; Wang, Yu-Nu; Hsu, Wen-Chuin; Huang, Tzu-Hsin; Lin, Yueh-E; Liu, Chin-Yi; Shyu, Yea-Ing L
2017-12-01
To examine the role of balancing competing needs in the relationship between caregiving demand and caregiving outcomes (caregivers' role strain and depressive symptoms). Caregivers who do not balance competing needs are more likely to experience negative caregiving outcomes, suggesting that balance mediates between caregiving demand and caregiving outcomes. Identifying a mediator of negative caregiving effects may help in developing tailored interventions for family caregivers of persons with dementia. A cross-sectional, correlational design. Data were collected from family caregivers' self-completed questionnaires between March 2013 - April 2014. A convenience sample of 120 family caregivers and care receivers with dementia was enrolled. We examined whether balance mediated the relationship between caregiving demand and caregiving outcomes (caregivers' role strain and depressive symptoms) by multiple regression analysis. To evaluate the significance of the indirect effect of caregiver balance, we used the Sobel test and Monte Carlo method, an alternative approach to testing mediation. Balancing competing needs completely mediated the association of caregiving demand with depressive symptoms and partially mediated the association of caregiving demand with role strain. Assessing caregivers' self-perceived sense of balance may help to identify caregivers at high risk for role strain and depressive symptoms. Interventions to enhance caregivers' perceived sense of balance between competing needs may provide a strategy for reducing the negative effects of caregiving. © 2017 John Wiley & Sons Ltd.
Yüksel, Özge; Dağ, İhsan
2015-01-01
The aim of this study were to investigate the mediator role of coping strategies and gender roles attitudes on the relationship between women's marital adjustment and psychological symptoms. 248 married women participated in the study. Participants completed Marital Adjustment Scale, Ways of Coping Questionnaire, Brief Symptom Inventory, Gender Role Attitudes Scale and Demographic Information Form. Regression analyses revealed that Submissive (Sobel z= -2.47, p<.01) and Helpless Coping Approach (Sobel z=-2.95, p<.001) have partial mediator role on the relationship between marital relationship score and psychological symptom level. Also, having Egalitarian Gender Role Attitude effects the psychological symptoms in relation with the marital relationship, but it is seen that this effect is not higher enough to play a mediator role (Sobel z =-1.21, p>.05). Regression analysis showed that there is a statistically significant correlation between women's marital adjustment and their psychological symptoms, indicating that the marital adjustment decreases as the psychological symptoms increases. It is also found out that submissive and helpless coping approach have mediator roles in this relationship. Also, contrary to expectations, having egalitarian gender role attitude effects the psychological symptoms in relation with the marital relationship, but this effect does not seem to play a mediator role. It is thought that the effects of marriage and couple therapy approaches considering coupless problem solving and coping styles should be examined in further studies.
Tompkins, Virginia; Logan, Jessica A R; Blosser, Daniel F; Duffy, Kaylin
2017-06-01
Achieving false belief understanding is an important cognitive milestone that allows children to understand that thoughts and reality can differ. Researchers have found that low-income children score significantly lower than middle-income children on false belief understanding but have not examined why this difference exists. We hypothesized that children's language and parent discipline mediate the income-false belief relation. Participants were 174 3- to 6-year-olds. False belief understanding was significantly correlated with family income, children's vocabulary, parents' self-reported discussion of children's behavior, discussion of emotions, and power assertion. Family income had a significant indirect effect on false belief understanding through children's vocabulary and parent discipline when examined independently, but only through children's vocabulary when using parallel multiple mediation. This study contributes to our knowledge of individual differences in false belief understanding. Copyright © 2017 Elsevier Inc. All rights reserved.
Developmental Climate: A Cross-level Analysis of Voluntary Turnover and Job Performance
Spell, Hannah B.; Eby, Lillian T.; Vandenberg, Robert J.
2014-01-01
This research investigates the influence of shared perceptions of developmental climate on individual-level perceptions of organizational commitment, engagement, and perceived competence, and whether these attitudes mediate the relationship between developmental climate and both individual voluntary turnover and supervisor-rated job performance. Survey data were collected from 361 intact employee-supervisory mentoring dyads and matched with employee turnover data collected one year later to test the proposed framework using multilevel modeling techniques. As expected, shared perceptions of developmental climate were significantly and positively related to all three individual work attitudes. In addition, both organizational commitment and perceived competence were significant mediators of the positive relationship between shared perceptions of developmental climate and voluntary turnover, as well as shared perceptions of developmental climate and supervisor-rated job performance. By contrast, no significant mediating effects were found for engagement. Theoretical implications, limitations, and future research are discussed. PMID:24748681
Wang, Xingchao; Lei, Li; Yang, Jiping; Gao, Ling; Zhao, Fengqing
2017-04-01
The link between empathy and aggression is well documented; yet, studies examining potential mechanisms that explain this association are limited. In the present study, we tested the relation between empathy and aggression and examined both the mediating and moderating effects of moral disengagement on this relation among Chinese male juvenile delinquents. Three hundred and fifty-seven male juvenile delinquents from one Chinese juvenile correctional facility completed the interpersonal reactivity index, the moral disengagement scale and the aggression questionnaire. The results indicated that moral disengagement partially mediated the influence of empathy on aggression. Moreover, moral disengagement moderated the relation between empathy and aggression. Specifically, there was a significant negative relation between empathy and aggression at low levels of moral disengagement. However, at high levels of moral disengagement, the relation between empathy and aggression was non-significant. The significance and limitations of the results are discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Yiting; Tu, Qunfei; Yan, Wei
Highlights: • CXC195 exhibited significant anti-proliferative effect and induced cell cycle arrest in LPS-induced HepG2 cells. • CXC195 suppressed the release of pro-inflammatory mediators in LPS-induced HepG2 cells. • CXC195 regulated TLR4-MyD88-TAK1-mediated NF-κB and MAPK pathway in LPS-induced HepG2 cells. - Abstract: CXC195 showed strong protective effects in neuronal apoptosis by exerting its antioxidant activity. However, the anti-cancer effects of CXC195 is still with limited acquaintance. Here, we investigated the role of CXC195 in lipopolysaccharide (LPS)-induced human hepatocellular carcinoma (HCC) cells lines (HepG2) and the possible signaling pathways. CXC195 exhibited significant anti-proliferative effect and induced cell cycle arrest in LPS-inducedmore » HepG2 cells. In addition, CXC195 suppressed the release of pro-inflammatory mediators in LPS-induced HepG2 cells, including TNF-α, iNOS, IL-1β, IL-6, CC chemokine ligand (CCL)-2, CCL-22 and epidermal growth factor receptor (EGFR). Moreover, CXC195 inhibited the expressions and interactions of TLR4, MyD88 and TAK1, NF-κB translocation to nucleus and its DNA binding activity, phosphorylation of ERK1/2, p38 and JNK. Our results suggested that treatment with CXC195 could attenuate the TLR4-mediated proliferation and inflammatory response in LPS-induced HepG2 cells, thus might be beneficial for the treatment of HCC.« less
Huang, Feifei; Chen, Jie; Liu, Xun; Han, Feng; Cai, Qingqing; Peng, Guicheng; Zhang, Kun; Chen, Weiqing; Wang, Jingfeng; Huang, Hui
2016-12-27
Elevated homocysteine (HCY) and smoking are both important risk factors for hypertensive patients. However, whether they have crossing effect on renal function deterioration of hypertensive patients and what is the underlying mechanism are unclear. In the present study, 3033 participants diagnosed as essential hypertension with estimated glomerular filtration rate (eGFR)> 30 ml/min/1.73 m2 from southern China were enrolled in this cross-sectional study. We collected the demographic and clinical data. In addition, the mediation effects were analyzed. The results showed that, comparing with non-smokers, smokers had significant higher levels of HCY (13.10 (11.20-16.87) vs. 11.00 (8.90-13.40) umol/L, P < 0.001) and lower eGFR (79.71 (66.83-91.05) vs. 82.89 (69.80-95.85) ml/min/1.73m2, P < 0.001). HCY levels and smoking were independently associated with decreased eGFR. Meanwhile, eGFR levels were significantly negatively correlated with HCY (P < 0.001), and this correlation might be stronger in current smokers. Current smoker consuming over 20 cigarettes per day would accelerate early renal function deterioration (OR = 1.859, P = 0.019). The mediation effects analysis further showed that the association between smoking and renal function deterioration was mediated by HCY. And elevated HCY was accounted for 56.94% of the estimated causal effect of smoking on renal function deterioration in hypertensive patients. Our findings indicated that cigarette smoking was associated with renal function deterioration in hypertensive patients, and the association between cigarette smoking and renal function deterioration was probably mediated by elevated HCY. Therefore, HCY-lowering therapy may be beneficial for renal function deterioration in hypertensive smoking patients.
Das, Sonjit; Joardar, Swarnalata; Dua, Tarun K.; Bhattacharjee, Niloy; Khanra, Ritu; Kalita, Jatin; Saha, Achintya; Ray, Supratim
2018-01-01
The present studies have been executed to explore the protective mechanism of carnosic acid (CA) against NaAsO2-induced hepatic injury. CA exhibited a concentration dependent (1–4 μM) increase in cell viability against NaAsO2 (12 μM) in murine hepatocytes. NaAsO2 treatment significantly enhanced the ROS-mediated oxidative stress in the hepatic cells both in in vitro and in vivo systems. Significant activation of MAPK, NF-κB, p53, and intrinsic and extrinsic apoptotic signaling was observed in NaAsO2-exposed hepatic cells. CA could significantly counteract with redox stress and ROS-mediated signaling and thereby attenuated NaAsO2-mediated hepatotoxicity. NaAsO2 (10 mg/kg) treatment caused significant increment in the As bioaccumulation, cytosolic ATP level, DNA fragmentation, and oxidation in the liver of experimental mice (n = 6). The serum biochemical and haematological parameters were significantly altered in the NaAsO2-exposed mice (n = 6). Simultaneous treatment with CA (10 and 20 mg/kg) could significantly reinstate the NaAsO2-mediated toxicological effects in the liver. Molecular docking and dynamics predicted the possible interaction patterns and the stability of interactions between CA and signal proteins. ADME prediction anticipated the drug-likeness characteristics of CA. Hence, there would be an option to employ CA as a new therapeutic agent against As-mediated toxic manifestations in future. PMID:29854073
Chien, Lung-Chang; Li, Xiao; Staudt, Amanda
2017-11-03
Physical inactivity is one of the risk factors of diabetes. In addition, physical inactivity is attributed to urbanization-related factors, such as poverty, which is also one of the risk factors of diabetes. We hypothesized that physical inactivity is a mediator in the association between diabetes and poverty, and that spatial heterogeneity exists in these relationships. This study adopted a spatiotemporal modelling approach to conduct this mediator analysis. From 2004-2011, data were collected at the county level in 48 contiguous states (with a total of 3,109 counties) from the Behavioral Risk Factor Surveillance System (BRFSS) and American Community Survey. Poverty percentage significantly affected physical inactivity prevalence and diabetes prevalence in two separate models. Using a model with both physical inactivity and poverty percentages as independent variables, we verified that physical inactivity prevalence is a significant mediator. In this model, physical inactivity prevalence resulted in a significant positive association with diabetes prevalence, and the influence of poverty percentage on diabetes prevalence was significantly reduced (P=0.0009). An advanced spatiotemporal analysis revealed that 32.65% of counties having a significant positive association between diabetes prevalence and physical inactivity prevalence also had a significant positive association between physical inactivity prevalence and poverty percentage. Those counties were also likely located in the South and Southeast of USA. In summary, the findings of this study demonstrate the mediating effect of physical inactivity between diabetes and poverty. When implementing diabetes prevention in communities with higher poverty, appropriate strategies to reduce the cost burden of physical activity programmes should be considered.
Early childhood malnutrition predicts depressive symptoms at ages 11-17.
Galler, J R; Bryce, C P; Waber, D; Hock, R S; Exner, N; Eaglesfield, D; Fitzmaurice, G; Harrison, R
2010-07-01
We examined the prevalence of depressive symptoms in Barbadian youth with histories of infantile malnutrition and in a healthy comparison group and the extent to which the effect of malnutrition was mediated/moderated by maternal depression. Depressive symptoms were assessed using a 20-item scale administered to youths (11-17 years of age) who had experienced an episode of protein-energy malnutrition (marasmus or kwashiorkor) during the first year of life and in a comparison group of healthy youths without a history of malnutrition. Their mothers completed the same questionnaire on the same test on three occasions when their children were 5-17 years of age at 2-5-year intervals. The prevalence of depressive symptoms was elevated among previously malnourished youth relative to healthy comparison children (p < .001). When youth depression scores were subjected to a longitudinal multiple regression analysis, adjusting for the effect of maternal depressive symptoms, significant effects due to the history of early childhood malnutrition remained and were not discernibly attenuated from an unadjusted analysis. We also found significant independent effects of maternal depressive symptoms on youth depressive symptoms. Early childhood malnutrition contributed independently to depressive symptoms in youths who experienced a significant episode of malnutrition in the first year of life. This relationship was not mediated or moderated by the effects of maternal depression. Whether the later vulnerability to depression is a direct effect of the episode of malnutrition and related conditions early in life or whether it is mediated by the more proximal neurobehavioral effects of the malnutrition remains to be determined.
Lee, Byung; Jeong, Seokjin; Roh, Myunghoon
2018-05-30
It is well-documented that obese children and adolescents tend to experience a variety of negative physical and psychological health consequences. Despite the association between obesity and physical and psychological well-being, few studies have examined the role of off-line and on-line forms of bullying victimization in this link. The main objective of the current study is to investigate the direct and mediating effects of traditional and cyber bullying victimization in explaining the relationship between the body mass index (BMI) and physical/psychological distress. A nationally representative sample of 10,160 school children (mean age = 12.95 ± 1.75) were collected from the 2009 Health Behavior in School-aged Children (HBSC) study. Data were collected on body mass index, physical and psychological health, bullying victimization experience, and demographic information. A seemingly unrelated regression (SUR) was employed to assess and compare the indirect effects in multiple mediation models. While a significant direct association was found between BMI and both physical and psychological health, the indirect effect of BMI on physical distress was significant only via traditional bullying victimization. Both forms of bullying victimization had a mediating impact between BMI and psychological distress. However, the indirect effect on psychological distress was manifested through a negative mediating role of cyberbullying victimization. The negative relation between cyberbullying victimization and psychological distress warrants further exploration. Obesity represents a serious risk to adolescent health and well-being, both physically and psychologically. If becoming a victim of traditional bullying mediates (specifically exacerbates) the level of physical and psychological distress among obese and overweight adolescents, health professionals need to focus on raising awareness of the importance of weight-based victimization for children and adolescents with obesity. School administrators and teachers could increase the efforts to identify school-age children who are stigmatized for their weight and recommend coping strategies for distressed victims of traditional and cyberbullying.
Empathy Mediates the Effects of Age and Sex on Altruistic Moral Decision Making
Rosen, Jan B.; Brand, Matthias; Kalbe, Elke
2016-01-01
Moral decision making involves affective and cognitive functions like emotional empathy, reasoning and cognitive empathy/theory of mind (ToM), which are discussed to be subject to age-related alterations. Additionally, sex differences in moral decision making have been reported. However, age-related changes in moral decision making from early to late adulthood and their relation to sex and neuropsychological functions have not been studied yet. One hundred ninety seven participants (122 female), aged 19–86 years, were tested with a moral decision making task comprising forced choice “everyday life” situations in which an altruistic option that favors a socially accepted alternative had to be considered against an egoistic option that favors personal benefit over social interests. The percentage of altruistic decisions was analyzed. A structural equation model (SEM) was calculated to test the hypothesis whether age and sex predict altruistic moral decision, and whether relevant neuropsychological domains mediate these hypothesized relationships. A significant relationship between age and moral decision making was found indicating more frequent altruistic decisions with increasing age. Furthermore, women decided more altruistically than men. The SEM showed that both age and sex are significant predictors of altruistic moral decision making, mediated by emotional empathy but not by reasoning. No cognitive empathy and ToM scores were correlated to age and moral decision making at the same time and thus were not included in the SEM. Our data suggest that increasing age and female sex have an effect on altruistic moral decisions, but that this effect is fully mediated by emotional empathy. The fact that changes of moral decision making with age are mediated by emotional empathy can be interpreted in the light of the so-called “positivity effect” and increasing avoidance of negative affect in aging. The mediated sex effect might represent both biological aspects and socialized sex roles for higher emotional empathy leading to more altruistic decisions. PMID:27147990
Allen, Karina L; Byrne, Susan M; Crosby, Ross D
2015-08-01
Binge eating disorder and purging disorder have gained recognition as distinct eating disorder diagnoses, but risk factors for these conditions have not yet been established. This study aimed to evaluate a prospective, mediational model of risk for the full range of binge eating and purging eating disorders, with attention to possible diagnostic differences. Specific aims were to determine, first, whether eating, weight and shape concerns at age 14 would mediate the relationship between parent-perceived childhood overweight at age 10 and a binge eating or purging eating disorder between age 15 and 20, and, second, whether this mediational model would differ across bulimia nervosa, binge eating disorder, and purging disorder. Participants (N = 1,160; 51 % female) were drawn from the Western Australian Pregnancy Cohort (Raine) Study, which has followed children from pre-birth to age 20. Eating disorders were assessed via self-report questionnaires when participants were aged 14, 17 and 20. There were 146 participants (82 % female) with a binge eating or purging eating disorder with onset between age 15 and 20 [bulimia nervosa = 81 (86 % female), binge eating disorder = 43 (74 % female), purging disorder = 22 (77 % female)]. Simple mediation analysis with bootstrapping was used to test the hypothesized model of risk, with early adolescent eating, weight and shape concerns positioned as a mediator between parent-perceived childhood overweight and later onset of a binge eating or purging eating disorder. Subsequently, a conditional process model (a moderated mediation model) was specified to determine if model pathways differed significantly by eating disorder diagnosis. In the simple mediation model, there was a significant indirect effect of parent-perceived childhood overweight on risk for a binge eating or purging eating disorder in late adolescence, mediated by eating, weight and shape concerns in early adolescence. In the conditional process model, this significant indirect effect was not moderated by eating disorder group. The results support a prospective model of risk that applies to bulimia nervosa, binge eating disorder and purging disorder. Common prevention approaches may be possible for bulimia nervosa, binge eating disorder and purging disorder.
Returns to scientific publications for pharmaceutical products in the United States.
Slejko, Julia F; Basu, Anirban; Sullivan, Sean D
2018-02-01
Drug-specific clinical and health economic and outcomes research (HEOR) publications have amassed, but their effect on drug sales is largely unknown. We estimated the impact of publications on pharmaceutical sales in 3 markets (statins, rheumatoid arthritis, and asthma drugs) with varying generic competition. An event-study approach with fixed effects and difference-in-fixed-effects modeling was used to estimate the causal effects of drug-specific publications on subsequent quarter's drug-specific sales and volume. High-impact clinical and HEOR publications have significant positive effects on sales (mediated through price) and volume in the statin market (high generic competition). High-impact clinical publications have a significant positive effect on sales (mediated through volume) in low-generic competition market (asthma). The effects of publications in the rheumatoid arthritis market (no generic competition) on sales were null. Manufacturers' investment in clinical and HEOR publications needs to be strategic and should be anticipated and complemented by public investments in such studies. Copyright © 2017 John Wiley & Sons, Ltd.
Ragusa, Rosetta; Cabiati, Manuela; Guzzardi, Maria Angela; D'Amico, Andrea; Giannessi, Daniela; Del Ry, Silvia; Caselli, Chiara
2017-04-01
Suppression of tumorigenicity 2 (ST2) mediates the effect of Interleukin-33 (IL-33). Few data are reported on the relationship between IL-33/ST2 and obesity. We aimed to investigate effects of obesity on IL-33/ST2 system in heart, adipose tissue and liver in a rodent model of obesity. The relationship of cardiac expression of IL-33/ST2 system with natriuretic peptides (NPs) system and inflammatory mediators was also studied. mRNA expression of IL-33/ST2 system was evaluated in cardiac, adipose and hepatic biopsies from obese Zucker rats (O) and controls (CO). Expression levels of sST2 was significantly lower in O rats compared with CO (p<0.05) in all tissues. Besides, the mRNA levels of IL-33 decreased significant in fat of O respect to CO, while, expression levels of ST2L was significantly higher in liver of CO than in O. A strong relationship of IL-33/ST2 with NPs and classical inflammatory mediators was observed in cardiac tissue. Expression of sST2 in cardiac, adipose and liver tissue decreased in O compared with controls, suggesting an involvement for IL-33/ST2 system in molecular mechanisms of obesity. The strong relationships with NP systems and inflammatory mediators could suggest an involvement for IL-33/ST2 in molecular pathways leading to cardiac dysfunction and inflammation associated with obesity. Copyright © 2017 Elsevier Inc. All rights reserved.
Magnusson Hanson, Linda L.; Peristera, Paraskevi; Chungkham, Holendro Singh; Westerlund, Hugo
2016-01-01
Lifestyle has been regarded as a key pathway through which adverse psychosocial working characteristics can give rise to long-term health problems. The purpose of this study was to estimate the indirect/mediated effect of health behaviors in the longitudinal work characteristics-depression relationship. The analyses were based on the Swedish Longitudinal Occupational Survey of Health, including 3706 working participants with repeat survey measures on four occasions (2008, 2010, 2012 and 2014). Psychosocial work characteristics including demands and social support were analyzed in relation to depressive symptoms. Autoregressive longitudinal mediation models using structural equation modeling were used to estimate the intermediate effects of unhealthy behaviors including current smoking, excessive alcohol consumption, unhealthy diet and physical inactivity. Both workplace demands and social support were related to later depressive symptoms. In bivariate models we found no significant paths from workplace demands to health behaviors, but two out of three significant time-specific paths from workplace support to excessive drinking and from excessive drinking to depressive symptoms. Social support was also associated with subsequent unhealthy diet, and one path from unhealthy diet to depressive symptoms was found. However, despite indications of certain longitudinal relationships between psychosocial working conditions and health behaviors as well as between health behaviors and depressive symptoms, no significant intermediate effects were found (p>0.05). We conclude that changes in unhealthy behaviors over a period of two years are unlikely to act as strong intermediaries in the longitudinal relationship between job demands and depressive symptoms and between social support and depressive symptoms. PMID:28036376
Magnusson Hanson, Linda L; Peristera, Paraskevi; Chungkham, Holendro Singh; Westerlund, Hugo
2016-01-01
Lifestyle has been regarded as a key pathway through which adverse psychosocial working characteristics can give rise to long-term health problems. The purpose of this study was to estimate the indirect/mediated effect of health behaviors in the longitudinal work characteristics-depression relationship. The analyses were based on the Swedish Longitudinal Occupational Survey of Health, including 3706 working participants with repeat survey measures on four occasions (2008, 2010, 2012 and 2014). Psychosocial work characteristics including demands and social support were analyzed in relation to depressive symptoms. Autoregressive longitudinal mediation models using structural equation modeling were used to estimate the intermediate effects of unhealthy behaviors including current smoking, excessive alcohol consumption, unhealthy diet and physical inactivity. Both workplace demands and social support were related to later depressive symptoms. In bivariate models we found no significant paths from workplace demands to health behaviors, but two out of three significant time-specific paths from workplace support to excessive drinking and from excessive drinking to depressive symptoms. Social support was also associated with subsequent unhealthy diet, and one path from unhealthy diet to depressive symptoms was found. However, despite indications of certain longitudinal relationships between psychosocial working conditions and health behaviors as well as between health behaviors and depressive symptoms, no significant intermediate effects were found (p>0.05). We conclude that changes in unhealthy behaviors over a period of two years are unlikely to act as strong intermediaries in the longitudinal relationship between job demands and depressive symptoms and between social support and depressive symptoms.
Ng, Thomas W H; Feldman, Daniel C
2014-07-01
Guided by conservation of resources theory, we propose that both organizational and community embeddedness are associated with increased work-to-family conflict (WFC) and family to-work conflict (FWC), which in turn are associated with strain-related outcomes. Because stress can have both short-term and long-term consequences, we examined negative mood as an immediate reaction to stress and chronic insomnia as a longer-term reaction to stress. We examined these relationships in 2-career couples in both the United States (n = 416) and Singapore (n = 400). Results provided full support for the mediating effects of WFC and FWC in the U.S. sample, with only limited support for those mediating effects in the Singaporean sample. In addition, we found that the effects of community embeddedness on FWC were significantly stronger in the U.S. sample than in the Singaporean sample.
Jiang, Shaohai
2017-03-01
In the United States, levels of emotional well-being remain low, with 40% of American adults reporting the experience of daily stress and excessive anxiety. The doctor-patient communication during medical encounters may play a significant role in improving people's emotional well-being. Based on Street and his colleagues' (2009) pathway mediation model linking communication to health outcomes, this paper illustrates a mechanism that underlies how patient-centered communication improves emotional well-being. The results showed that patient-centered communication had direct effects on emotional well-being. In addition to the direct effects, patient-centered communication also indirectly influenced emotional well-being, mediated by patient satisfaction and emotion management, supporting the partial mediation. The findings provide additional empirical evidence to the pathways from communication to health outcomes, one of the least developed areas of communication research, and also offer significant implications for the design of interventions to improve patients' emotional well-being.
Shih, Stephannie; Huang, Yen-Tsung; Yang, Hwai-I
2018-06-01
Previous work suggested a genetic component affecting the risk of hepatocellular carcinoma (HCC) and mediation analyses have elucidated potential indirect pathways of these genetic effects. Specifically, the effects of alcohol dehydrogenase (ADH1B) and aldehyde dehydrogenase (ALDH2) genes on HCC risk vary based on alcohol consumption habits. However, alcohol consumption may not be the only mediator in the identified pathway: factors related to alcohol consumption may contribute to the same indirect pathway. Thus, we developed a multimediator model to quantify the genetic effects on HCC risk through sequential dichotomous mediators under the counterfactual framework. Our method provided a closed form formula for the mediation effects through different indirect paths, which requires no assumption for the rarity of outcome. In simulation studies of a finite sample, we presented the utility of the method with the variance of the effects estimated using the delta method and bootstrapping. We applied our method to data from participants in Taiwan (580 cases and 3,207 controls) and quantified the mediation effects of single nucleotide polymorphisms (SNPs) in the ADH1B and ALDH2 genes on HCC through alcohol consumption (yes/no) and high alanine transaminase (ALT) levels (greater than or equal to 45 U/L or below 45 U/L). Assuming a dominant risk model, we identified that the SNPs' effects through alcohol consumption is more significant than through ALT levels on HCC risk. This new method provides insight to the magnitude of various casual mechanisms as a closed form solution and can be readily applied in other genomic studies. © 2018 WILEY PERIODICALS, INC.
Jekauc, Darko; Wagner, Matthias Oliver; Herrmann, Christian; Hegazy, Khaled; Woll, Alexander
2017-01-01
The purpose of this study is to examine the reciprocal relationship between motor abilities and physical activity and the mediation effects of physical self-concept in this relationship using longitudinal data. We expect that the effects of motor abilities on physical activity are rather indirect via physical self-concept and that the effects of physical activity on motor abilities are rather direct without involvement of the motor ability self-concept. Data was obtained from the Motorik-Modul (MoMo) Longitudinal Study in which 335 boys and 363 girls aged 11–17 years old at Baseline were examined twice in a period of six years. Physical activity was assessed by the MoMo Physical Activity Questionnaire for adolescents, physical self-concept by Physical Self-Description Questionnaire and motor abilities by MoMo Motor Test which comprised of the dimensions strength, endurance, coordination and flexibility. Multiple regression analyses were used to analyse the direct and indirect effects. The results of the multiple regression analyses show that the effects of motor abilities on physical activity were only indirect for the dimensions strength, coordination, and flexibility. For the dimension endurance, neither direct nor indirect effects were significant. In the opposite direction, the effects of physical activity on motor abilities were partially mediated by the self-concept of strength. For the dimensions endurance, coordination and flexibility, only indirect were significant. The results of this study support the assumption that the relationship between motor abilities and physical activity is mediated by physical self-concept in both directions. Physical self-concept seems to be an important determinant of adolescents´ physical activity. PMID:28045914
Jekauc, Darko; Wagner, Matthias Oliver; Herrmann, Christian; Hegazy, Khaled; Woll, Alexander
2017-01-01
The purpose of this study is to examine the reciprocal relationship between motor abilities and physical activity and the mediation effects of physical self-concept in this relationship using longitudinal data. We expect that the effects of motor abilities on physical activity are rather indirect via physical self-concept and that the effects of physical activity on motor abilities are rather direct without involvement of the motor ability self-concept. Data was obtained from the Motorik-Modul (MoMo) Longitudinal Study in which 335 boys and 363 girls aged 11-17 years old at Baseline were examined twice in a period of six years. Physical activity was assessed by the MoMo Physical Activity Questionnaire for adolescents, physical self-concept by Physical Self-Description Questionnaire and motor abilities by MoMo Motor Test which comprised of the dimensions strength, endurance, coordination and flexibility. Multiple regression analyses were used to analyse the direct and indirect effects. The results of the multiple regression analyses show that the effects of motor abilities on physical activity were only indirect for the dimensions strength, coordination, and flexibility. For the dimension endurance, neither direct nor indirect effects were significant. In the opposite direction, the effects of physical activity on motor abilities were partially mediated by the self-concept of strength. For the dimensions endurance, coordination and flexibility, only indirect were significant. The results of this study support the assumption that the relationship between motor abilities and physical activity is mediated by physical self-concept in both directions. Physical self-concept seems to be an important determinant of adolescents´ physical activity.