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Activation System (activation + system)
Kinds of Activation System Selected AbstractsPhysiological and neuropsychological correlates of approach/withdrawal tendencies in preschool: Further examination of the behavioral inhibition system/behavioral activation system scales for young childrenDEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2004Clancy Blair Abstract This study examined a parent-report version of the Behavioral Inhibition System/Behavioral Activation System (BIS/BAS) scales, a measure of approach,withdrawal motivation, in 170 children between the ages of 3 to 5 years attending Head Start programs. Physiological measures included assessments of baseline salivary cortisol and change in cortisol in response to the assessment session, and resting and suppression estimates of cardiac vagal tone. Cognitive self-regulation was assessed with a peg-tapping measure of inhibitory control and an item-selection measure of cognitive set-shifting ability. Results indicated that higher level of parent-reported withdrawal motivation was associated with cortisol increase and that parent-reported approach motivation tended to be associated with cortisol decrease across the assessment session. Higher level of parent-reported withdrawal also was positively related to cognitive self-regulation while parent-reported approach was negatively related to cognitive self-regulation. Person-oriented analysis indicated that children characterized by both high level of approach and high level of withdrawal tended to exhibit lower resting vagal tone, higher initial cortisol, and minimal cortisol and vagal change. Overall, findings suggest that the parent-report version of the BIS/BAS scales works well as an indicator of children's reactivity to appetitive and aversive motivational stimuli. Directions for future research and implications of findings for the longitudinal study of temperament and personality are discussed. © 2004 Wiley Periodicals, Inc. Dev Psychobiol 45: 113-124, 2004. [source] Neurocognitive components of the behavioral inhibition and activation systems: Implications for theories of self-regulationPSYCHOPHYSIOLOGY, Issue 1 2008David M. Amodio Abstract We examined the neurocognitive correlates of the Behavioral Inhibition and Behavioral Activation Systems (BIS/BAS) in an effort to clarify ambiguities concerning interpretations of BIS as reflecting inhibition versus avoidance. We hypothesized that self-reported BIS should relate to neural mechanisms associated with conflict monitoring, whereas self-reported BAS should be associated with neural correlates of approach motivation. Consistent with these predictions, higher self-reported BIS was uniquely related to the N2 event-related potential on No-Go trials of a Go/No-Go task, linking BIS with conflict monitoring and sensitivity to No-Go cues. Higher BAS was uniquely related to greater left-sided baseline frontal cortical asymmetry associated with approach orientation. Implications for theories of self-regulation involving conflict monitoring, cognitive control, and approach/avoidance motivation are discussed. [source] Disinhibitory trait profile and its relation to Cluster B personality disorder features and substance use problemsEUROPEAN JOURNAL OF PERSONALITY, Issue 4 2006Jeanette Taylor Abstract Certain personality and motivational traits may present vulnerability towards disinhibitory psychopathology (e.g. antisocial personality disorder, substance abuse). Cluster analysis was used to separately group 306 women and 274 men on impulsivity, Constraint, Negative Emotionality, behavioural activation system (BAS), and behavioural inhibition system (BIS) scores. As expected, a ,disinhibited' group with low Constraint, high impulsivity, weak BIS, and strong BAS emerged that showed elevated drug use problems, and histrionic and antisocial personality disorder features across gender. A ,high affectivity' group with high Negative Emotionality and strong BIS also showed elevated drug use problems and personality disorder features. Results suggested that two different trait profiles are associated with disinhibitory psychopathology and both may present vulnerability toward the development of such disorders. Copyright © 2006 John Wiley & Sons, Ltd. [source] The assessment of behavioural activation,the relationship between positive emotionality and the behavioural activation systemEUROPEAN JOURNAL OF PERSONALITY, Issue 7 2004Lena C. Quilty Much personality research suggests that the variance in personality can be accounted for by a few dimensions, often hypothesized to be connected to neurological circuits. Gray's (1982) behavioural activation system (BAS) and behavioural inhibition system (BIS) in particular propose to explain for a variety of behaviour. This investigation sought to determine whether Positive Emotionality is an appropriate measure of the BAS, and how Tellegen's (1985) constructs are related to BAS activity. Measures of BAS and Positive Emotionality were administered to undergraduates. Confirmatory factor analyses revealed that, while Positive Emotionality can be used as an indicator of BAS activity, it is better conceived of as a distinct, correlated construct. In addition, not all components of Positive Emotionality were related to BAS activity, and BAS was further related to components of Negative Emotionality and Constraint. Copyright © 2004 John Wiley & Sons, Ltd. [source] Suppression of urokinase receptor expression by bikunin is associated with inhibition of upstream targets of extracellular signal-regulated kinase-dependent cascadeFEBS JOURNAL, Issue 16 2002Hiroshi Kobayashi Our laboratory showed that bikunin, a Kunitz-type protease inhibitor, suppresses 4,-phorbol 12-myristate 13-acetate (PMA)- or tumor necrosis factor-alpha (TNF,)-induced urokinase-type plasminogen activator (uPA) expression in different cell types. In addition to its effects on protease inhibition, bikunin could be modulating other cellular events associated with the metastatic cascade. To test this hypothesis, we examined whether bikunin was able to suppress the expression of uPA receptor (uPAR) mRNA and protein in a human chondrosarcoma cell line, HCS-2/8, and two human ovarian cancer cell lines, HOC-I and HRA. The present study showed that (a) bikunin suppresses the expression of constitutive and PMA-induced uPAR mRNA and protein in a variety of cell types; (b) an extracellular signal-regulated kinase (ERK) activation system is necessary for the PMA-induced increase in uPAR expression, as PD098059 and U0126, which prevent the activation of MEK1, reduce the uPAR expression; (c) bikunin markedly suppresses PMA-induced phosphorylation of ERK1/2 at the concentration that prevents uPAR expression, but does not reduce total ERK1/2 antigen level; (d) bikunin has no ability to inhibit overexpression of uPAR in cells treated with sodium vanadate; and (e) we further studied the inhibition of uPAR expression by stable transfection of HRA cells with bikunin gene, demonstrating that bikunin secretion is necessary for inhibition of uPAR expression. We conclude that bikunin downregulates constitutive and PMA-stimulated uPAR mRNA and protein possibly through suppression of upstream targets of the ERK-dependent cascade, independent of whether cells were treated with exogenous bikunin or transfected with bikunin gene. [source] E2F1-mediated transcriptional inhibition of the plasminogen activator inhibitor type 1 geneFEBS JOURNAL, Issue 18 2001Magdalena Koziczak ,Gene expression of the plasminogen activation system is cell-cycle dependent. Previously, we showed that ectopic expression of E2F1 repressed the plasminogen activator inhibitor type 1 (PAI-1) promoter in a manner dependent on the presence of DNA-binding and transactivation domains of E2F1 but independent of binding to pocket-binding proteins, suggesting a novel mechanism for E2F-mediated negative gene regulation [Koziczak, M., Krek, W. & Nagamine, Y. (2000) Mol. Cell. Biol.20, 2014,2022]. However, it remains to be seen whether endogenous E2F can exert a similar effect. We report here that down-regulation of PAI-1 gene expression correlates with an increase in endogenous E2F activity. When cells were treated with a cdk2/4-specific inhibitor, which maintains E2F in an inactive state, the decline of serum-induced PAI-1 mRNA levels was suppressed. In mutant U2OS cells expressing a temperature-sensitive retinoblastoma protein (pRB), a shift to a permissive temperature induced PAI-1 mRNA expression. In U2OS cells stably expressing an E2F1-estrogen receptor chimeric protein that could be activated by tamoxifen, PAI-1 gene transcription was markedly reduced by tamoxifen even in the presence of cycloheximide. These results all indicate that endogenous E2F can directly repress the PAI-1 gene. DNase I hypersensitive-site analysis of the PAI-1 promoter suggested the involvement of conformation changes in chromatin structure of the PAI-1 promoter. 5, deletion analysis of the PAI-1 promoter showed that multiple sites were responsible for the E2F negative regulation, some of which were promoter dependent. Interestingly, one of these sites is a p53-binding element. [source] Smoking, Mood Regulation, and Personality: An Event-Sampling Exploration of Potential Models and ModerationJOURNAL OF PERSONALITY, Issue 3 2007Nima G. Moghaddam ABSTRACT The aim of the present study was to test potential models of smoking-related changes in mood and how these are moderated by personality (behavioral activation and inhibition systems). Three models yielding distinct predictions regarding mood changes associated with cues to smoking and effects of ingestion were identified: the negative reinforcement model, the appetitive-incentive model, and the incentive-sensitization model. Seventy participants provided baseline data on personality and mood, and subsequently monitored their smoking behavior over 48 hours using an event-contingent diary,eliciting reports of mood state immediately prior to, and after, each cigarette smoked. MANOVA and multilevel modeling indicated that mood (hedonic tone and energetic arousal) improved significantly (p<.001) from baseline to pre-smoking, but did not change from pre- to post-smoking, thereby supporting the incentive-sensitization model. Further multilevel analyses indicated that significant variability in hedonic tone was moderated by the behavioral activation system. [source] pOp6/LhGR: a stringently regulated and highly responsive dexamethasone-inducible gene expression system for tobaccoTHE PLANT JOURNAL, Issue 6 2005Marketa Samalova Summary We describe pOp/LhGR, a dexamethasone-inducible derivative of the pOp/LhG4 transcription activation system, and its use in tobacco to regulate expression of uidA (encoding , -glucuronidase; GUS) and the cytokinin-biosnythetic gene ipt. The pOp/LhGR system exhibited stringent regulation and strong induced phenotypes in soil and tissue culture. In conjunction with an improved target promoter, pOp6, that carries six copies of an optimized lac operator sequence the pOp6/LhGR system directed induced GUS activities that exceeded those obtained with pOp/LhG4 or the CaMV 35S promoter but without increased uninduced activity. A single dose of dexamethasone was sufficient to direct cytotoxic levels of ipt expression in soil-grown plants although uninduced plants grew normally throughout a complete life cycle. In vitro, induced transcripts were detectable within an hour of dexamethasone application and 1 nm dexamethasone was sufficient for half maximal induction of GUS activity. Various methods of dexamethasone application were successfully applied under tissue culture and greenhouse conditions. We observed no inhibitory effects of dexamethasone or LhGR on plant development even with the highest concentrations of inducer, although tobacco seedlings were adversely affected by ethanol used as a solvent for dexamethasone stock solutions. The pOp/LhGR system provides a highly sensitive, efficient, and tightly regulated chemically inducible transgene expression system for tobacco plants. [source] Activated protein C levels in Behçet's disease and risk of venous thrombosisBRITISH JOURNAL OF HAEMATOLOGY, Issue 4 2004Silvia Navarro Summary Behçet's disease is a multi-systemic inflammatory disorder of unknown cause. Most abnormalities have been associated with endothelial injury caused by vasculitis. Thrombosis occurs in about 25% of patients, although the mechanism is unknown. The objective of this study was to evaluate the protein C activation system in Behçet's disease and its correlation with venous thromboembolism (VTE). Thirty-nine patients (12 with VTE) and 78 age- and sex-matched controls were included in the study, and levels of protein C, protein S, activated protein C (APC), protein C inhibitor (PCI), soluble thrombomodulin (TM), antithrombin (AT), ,1 -antitrypsin, fibrinogen, factor VIII, von Willebrand factor (VWF) and C-reactive protein (CRP) were measured. APC and TM levels were significantly lower in patients than in controls, whereas protein S, AT, ,1 -antitrypsin, fibrinogen, factor VIII, VWF and CRP levels were significantly higher in patients than in controls. APC, PCI and TM levels were lower in patients with VTE (0·65 ± 0·19 ng/ml, 86% ± 22% and 15·5 ± 7·1 ng/ml respectively) than in those without VTE (0·78 ± 0·17 ng/ml, 100% ± 15% and 22·1 ± 15·3 ng/ml) (P < 0·05). In patients, APC levels below 0·75 ng/ml (10th percentile of the control group) increased the risk of VTE about fivefold (odds ratio = 5·1; 95% confidence interval = 1·1,23·4). These results show that reduced APC levels are associated with the high incidence of VTE in Behçet's disease. [source] Complex of urokinase-type plasminogen activator with its type 1 inhibitor predicts poor outcome in 576 patients with lymph node,negative breast carcinomaCANCER, Issue 3 2004Peggy Manders M.Sc. Abstract BACKGROUND The ability of a solid tumor to grow and metastasize has a significant dependence on protease systems, such as the plasminogen activation system. The plasminogen activation system includes the urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor type 1 (PAI-1), among other molecules. Both uPA and PAI-1 are established prognostic factors for patients with breast carcinoma. In the current study, the authors investigated whether the complex of uPA with PAI-1 is also associated with the natural course of this malignancy. METHODS Cytosolic levels of uPA, PAI-1, and the uPA:PAI-1 complex were measured in tumor tissue from 576 patients with lymph node,negative invasive breast carcinoma using quantitative enzyme-linked immunosorbent assays. Patients did not receive adjuvant systemic therapy, and the median follow-up duration was 61 months (range, 2,187 months) after primary diagnosis. Correlations with well known clinicopathologic factors were assessed, and univariate and multivariate survival analyses were performed. RESULTS uPA:PAI-1 complex levels were positively associated with adverse histologic grade and inversely correlated with estrogen and progesterone receptor status. On univariate analysis, increased levels of the uPA:PAI-1 complex were found to be associated with reduced recurrence-free survival (RFS) and overall survival (OS) rates. On multivariate analysis, uPA:PAI-1 complex levels were found to be an independent predictor of OS (P = 0.039), but not RFS (P = 0.240). When uPA and PAI-1 levels were not included in the multivariate analysis, uPA:PAI-1 complex levels became a significant predictor of both RFS and OS (P = 0.029 and P = 0.007, respectively). CONCLUSIONS The results of the current study demonstrate that uPA:PAI-1 complex levels have prognostic value on univariate analysis. In addition, increased uPA:PAI-1 complex levels were significantly associated with poor OS on multivariate analysis. Increased uPA:PAI-1 complex levels were also significantly associated with reduced RFS rates after the exclusion of uPA and PAI-1 levels from the multivariate analysis model. Cancer 2004. © 2004 American Cancer Society. [source] Uveal melanoma and macular degeneration: molecular biology and potential therapeutic applicationsACTA OPHTHALMOLOGICA, Issue 8 2008Mario-Alexander Economou Abstract. Uveal melanoma is the most common primary intraocular malignant tumor in adults with 30% to 50% of patients that ultimately succumb to metastatic disease, mainly to the liver. (Shields et al. 1991) Although new diagnostic and therapeutic tools have been developed during the most recent years, only the eye conservation rate has been achieved, while the survival rate remains poor. The reason for this liver-homing is largely unknown, but it is conceivable that hepatic environmental factors may be implicated in the growth, dissemination, and progression of this malignancy. The insulin-like growth factor (IGF-1) that binds to the IGF-1 receptor (IGF-1R) is mainly produced in the liver. It has been shown to be crucial for tumor transformation, maintenance of malignant phenotype, promotion of cell growth, and prevention of apoptosis. (Baserga 1995) The hepatocyte growth factor/scatter factor (HGF/SF) is another growth factor produced in the liver and exerts its biological effects through binding to the plasma membrane receptor c-Met. The activation of this receptor by HGF/SF ligand can induce proliferation, motility, adhesion, and invasion of tumor cells. (Cruz et al. 2003) Metastasis is a process involving many components, including tumor cell adhesion, migration, extracellular matrix (ECM) proteolysis, and invasion. The tumor cells undergo intravasation, disperse via the vascular and the lymphatic systems, and finally extravasate to invade the secondary sites. In all these steps, proteolytic enzyme systems are involved, including the matrix metalloproteinase (MMP) system and the plasminogen activation system. The migration of a malignant cell through the ECM and the basement membrane requires proteolytic activities. (Stetler-Stevenson et al. 1993). Efforts to target the IGF-I system has been made with different types of cancer but not with uveal melanoma. [source] Persuasion and the structure of affect.HUMAN COMMUNICATION RESEARCH, Issue 1 2001Dual systems, discrete emotions as complementary models Participants viewed eight PSAs, providing data on their cognitive and emotional responses to each, as well as judgments of the perceived effectiveness of the messages. They also responded to Carver and White's (1994) BIS/BAS scales designed to measure individual differences in the behavioral inhibition and behavioral activation systems. Consistent with dual-systems theories of affect, the BIS scales predicted arousal of negative emotions, while BAS was associated with the elicitation of positive emotions. However, when predicting perceived message effectiveness, the positive affects showed variation in the sign and magnitude of the coefficients, as did the negative affects. This latter finding supports a discrete-emotions perspective. Knowledge that the two affect structures are appropriate to different conceptual domains (i.e., elicitation vs. effect) should enable researchers to formulate more precise questions regarding the role of affect in persuasion. [source] Multiple-Well, multiple-path unimolecular reaction systems.INTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 4 2001Vibrationally excited 2-methylhexyl radicals formed by shock wave activation or by chemical activation can isomerize by multiple pathways to form any of six stable isomers, can fragment by multiple CH and CC bond fission pathways, and can be collisionally stabilized. Master equation simulations of chemical activation and of shock wave activation are used to explore the generic behavior of this complicated coupled system. Selecting the argon pressure in chemical activation systems that produce the 2-methyl-1-hexyl radical isomer (1) can control the yield of specific isomers. Shock heating of 1 also shows a highly regular sequence of isomer formation. This regular behavior is because the first isomerization steps are faster than subsequent steps. Other radical isomers, such as 2-methyl-3-hexyl (3), do not show such regular behavior, because the first isomerization step is slower than subsequent steps. Incubation and unimolecular rate-constant fall-off are observed in the shock wave simulations. The unimolecular rate-constant fall-off for the coupled system produces low-pressure limiting rate constants proportional to [M]n, where n can be greater than unity. The fact that n can be greater than unity is a natural feature of multichannel coupled unimolecular reaction systems, but detection of the effect in experiments may be very demanding. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 246,261, 2001 [source] Neurocognitive components of the behavioral inhibition and activation systems: Implications for theories of self-regulationPSYCHOPHYSIOLOGY, Issue 1 2008David M. Amodio Abstract We examined the neurocognitive correlates of the Behavioral Inhibition and Behavioral Activation Systems (BIS/BAS) in an effort to clarify ambiguities concerning interpretations of BIS as reflecting inhibition versus avoidance. We hypothesized that self-reported BIS should relate to neural mechanisms associated with conflict monitoring, whereas self-reported BAS should be associated with neural correlates of approach motivation. Consistent with these predictions, higher self-reported BIS was uniquely related to the N2 event-related potential on No-Go trials of a Go/No-Go task, linking BIS with conflict monitoring and sensitivity to No-Go cues. Higher BAS was uniquely related to greater left-sided baseline frontal cortical asymmetry associated with approach orientation. Implications for theories of self-regulation involving conflict monitoring, cognitive control, and approach/avoidance motivation are discussed. [source] Influence of Alcohol Use Experience and Motivational Drive on College Students' Alcohol-Related CognitionALCOHOLISM, Issue 8 2009Roisin M. O'Connor Background:, Cognitive processes are thought to be pivotal to risk for heavy drinking. However, few studies have examined the alcohol cue-activated positive and negative semantic memory networks that may be pivotal to drinking behavior. Moreover, much is to be understood about the influences of cognitive processes, particularly in high-risk drinking samples such as college students. The current study examines the sequential process of alcohol cues activating valenced semantic memory networks, and the influences of prior drinking experience and individual differences in motivational drive on this automatic (implicit) cognitive process. Methods:, Participants (N = 138, 52% women) were college freshmen prescreened to represent the full range of drinking experience (i.e., current abstainers, light and heavy drinkers). Participants completed self-reports of past month alcohol use, and individual differences in behavioral inhibition system (BIS) and behavioral approach/activation system (BAS). Alcohol cue-elicited positive and negative semantic memory networks were assessed using a priming task. Results:, Results from the priming task revealed that for light drinkers alcohol cues were equally as likely to activate positive and negative semantic memory networks, suggesting relatively neutral cue-elicited alcohol attitudes. Conversely, for heavy drinkers, alcohol cues more readily activated positive relative to negative semantic memory networks, suggesting relatively positive cue-elicited alcohol attitudes. Furthermore, positive alcohol cue-elicited semantic memory networks (positive attitudes) were evident for individuals characterized by a strong BAS and weak BIS (as hypothesized) and those characterized by a weak BAS and weak BIS. Conclusions:, The findings suggest that alcohol-cue elicited positive semantic memory networks may be pivotal to risk for heavy drinking. Specifically, it is via the influence on this cognitive process that prior drinking experience and individual differences in motivational drive, respectively, may maintain and predispose individuals to risk for heavy alcohol use. [source] | |||||||||||||||||||