Am J Physiol Heart Circ Physiol
April 2012
The serine proteases, along with their inhibitor plasmin activator inhibitor-1 (PAI-1), have been shown to play a role in abdominal aortic aneurysm (AAA) formation. The aim of this study is to determine if PAI-1 may be a protective factor for AAA formation and partially responsible for the gender difference observed in AAAs. Male and female wild-type (WT) C57BL/6 and PAI-1(-/-) mice 8-12 wk of age underwent aortic perfusion with porcine pancreatic elastase.
View Article and Find Full Text PDFHerein, we demonstrate that the bacterial signaling molecule, c-di-GMP, can enhance the peroxidation of hemin when proflavine is present. The c-di-GMP-proflavine-hemin nucleotidezyme can oxidize the colorless compound 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), ABTS, to the colored radical cation ABTS˙(+) and hence provides simple colorimetric detection of c-di-GMP at low micromolar concentrations.
View Article and Find Full Text PDFThe Differential Radial Capillary Action of Ligand Assay (DRaCALA) allows detection of protein interactions with low-molecular weight ligands based on separation of the protein-ligand complex by differential capillary action. Here, we present an application of DRaCALA to the study of nucleic acid-protein interactions using the Escherichia coli cyclic AMP receptor protein (CRP). CRP bound in DRaCALA specifically to (32)P-labeled oligonucleotides containing the consensus CRP binding site, but not to oligonucleotides with point mutations known to abrogate binding.
View Article and Find Full Text PDFNeuroticism and extraversion are personality factors associated with the vulnerability for developing depression and anxiety disorders, and are possibly differentially related to brain structures implicated in the processing of emotional information and the generation of mood states. To date, studies on brain morphology mainly focused on neuroticism, a dimension primarily related to negative affect, yielding conflicting findings concerning the association with personality, partially due to methodological issues and variable population samples under study. Recently, extraversion, a dimension primarily related to positive affect, has been repeatedly inversely related to with symptoms of depression and anxiety disorders.
View Article and Find Full Text PDFWhen dealing with emotional situations, we often need to rapidly override automatic stimulus-response mappings and select an alternative course of action [1], for instance, when trying to manage, rather than avoid, another's aggressive behavior. The anterior prefrontal cortex (aPFC) has been linked to the control of these social emotional behaviors [2, 3]. We studied how this control is implemented by inhibiting the left aPFC with continuous theta burst stimulation (cTBS; [4]).
View Article and Find Full Text PDFWe investigated a) the concurrent impact of positive and negative life events on the course of depressive symptoms in persons remitted from depression and healthy controls, b) whether the impact of life events on symptom course is moderated by the history of depression and the personality traits of neuroticism and extraversion, and c) whether life events mediate possible relationships of history of depression and personality traits with symptom course. Using data from the Netherlands Study of Depression and Anxiety, we examined 239 euthymic participants with a previous depressive disorder based on DSM-IV and 450 healthy controls who completed a) baseline assessments of personality dimensions (NEO Five-Factor Inventory) and depression severity (Inventory of Depressive Symptoms [IDS]) and b) 1-year follow-up assessments of depression severity and the occurrence of positive and negative life events during the follow-up period (List of Threatening Events Questionnaire). Remitted persons reported higher IDS scores at 1-year follow-up than did the controls.
View Article and Find Full Text PDFInteractions of proteins with low-molecular-weight ligands, such as metabolites, cofactors, and allosteric regulators, are important determinants of metabolism, gene regulation, and cellular homeostasis. Pharmaceuticals often target these interactions to interfere with regulatory pathways. We have developed a rapid, precise, and high-throughput method for quantitatively measuring protein-ligand interactions without the need to purify the protein when performed in cells with low background activity.
View Article and Find Full Text PDFObjective: To examine the prognostic value of personality dimensions and negative and positive life events for diagnostic and symptom course trajectories in depressive and anxiety disorder.
Method: A total of 1209 subjects (18-65 years) with depressive and/or anxiety disorder were recruited in primary and specialized mental health care. Personality dimensions at baseline were assessed with the NEO-FFI and incidence and date of life events retrospectively with a structured interview at 2-year follow-up.
In the present study, we investigated the effect of prior aversive life events on freezing-like responses. Fifty healthy females were presented neutral, pleasant, and unpleasant images from the International Affective Picture System while standing on a stabilometric platform and wearing a polar band to assess body sway and heart rate. In the total sample, only unpleasant pictures elicited reduced body sway and reduced heart rate (freezing).
View Article and Find Full Text PDFIntroduction: Psychogenic Non Epileptic Seizures (PNES) have been theorized to reflect a learned pattern of avoidant behavior to deal with stressors. Although such observation may be relevant for our understanding of the etiology of PNES, evidence for this theory is largely build on self-report investigations and no studies have systematically tested actual avoidance behavior in patients with PNES. In this study, we tested automatic threat avoidance tendencies in relation to stress and cortisol levels in patients with PNES and healthy controls (HCs).
View Article and Find Full Text PDFFacial expressions are potent social cues that can induce behavioral dispositions, such as approach-avoidance tendencies. We studied these tendencies by asking participants to make whole-body forward (approach) or backward (avoidance) steps on a force plate in response to the valence of social cues (happy or angry faces) under affect-congruent and incongruent mappings. Posturographic parameters of the steps related to automatic stimulus evaluation, step initiation (reaction time), and step execution were determined and analyzed as a function of stimulus valence and stimulus-response mapping.
View Article and Find Full Text PDFRecently, there has been an explosion of research activities in the cyclic dinucleotides field. Cyclic dinucleotides, such as c-di-GMP and c-di-AMP, have been shown to regulate bacterial virulence and biofilm formation. c-di-GMP can exist in different aggregate forms, and it has been demonstrated that the polymorphism of c-di-GMP is influenced by the nature of cation that is present in solution.
View Article and Find Full Text PDFIt is clear that the steroid hormone testosterone plays an important role in the regulation of social emotional behavior, but it remains unknown which neural circuits mediate these hormonal influences in humans. We investigated the modulatory effects of endogenous testosterone on the control of social emotional behavior by applying functional magnetic resonance imaging while healthy male participants performed a social approach-avoidance task. This task operationalized social emotional behavior by having participants approach and avoid emotional faces by pulling and pushing a joystick, respectively.
View Article and Find Full Text PDFThe human stress hormone cortisol may facilitate effective coping after psychological stress. In apparent agreement, administration of cortisol has been demonstrated to reduce fear in response to stressors. For anxious patients with phobias or posttraumatic stress disorder this has been ascribed to hypothetical inhibition of retrieval of traumatic memories.
View Article and Find Full Text PDFAlthough psychogenic nonepileptic seizures (PNES) are considered a stress-induced paroxysmal disintegration of cognitive functions, it remains unknown whether stress indeed impairs cognitive integrative functions, such as working memory (WM), in patients with PNES. An N-back task with emotional distracters (angry, happy, and neutral faces) was administered at baseline and after stress induction (Cold Pressor Test) to 19 patients with PNES and 20 matched healthy controls. At baseline, patients displayed increased WM interference for the facial distracters.
View Article and Find Full Text PDFFreezing is a common defensive response in animals threatened by predators. It is characterized by reduced body motion and decreased heart rate (bradycardia). However, despite the relevance of animal defense models in human stress research, studies have not shown whether social threat cues elicit similar freeze-like responses in humans.
View Article and Find Full Text PDFConversion disorder is characterized by neurological signs and symptoms related to an underlying psychological issue. Amygdala activity to affective stimuli is well characterized in healthy volunteers with greater amygdala activity to both negative and positive stimuli relative to neutral stimuli, and greater activity to negative relative to positive stimuli. We investigated the relationship between conversion disorder and affect by assessing amygdala activity to affective stimuli.
View Article and Find Full Text PDFBackground: Although several studies have shown that life adversities play an important role in the etiology and maintenance of both depressive and anxiety disorders, little is known about the relative specificity of several types of life adversities to different forms of depressive and anxiety disorder and the concurrent role of neuroticism. Few studies have investigated whether clustering of life adversities or comorbidity of psychiatric disorders critically influence these relationships.
Methods: Using data from the Netherlands Study of Depression and Anxiety (NESDA), we analyzed the association of childhood adversities and negative life experiences across the lifespan with lifetime DSM-IV-based diagnoses of depression or anxiety among 2288 participants with at least one affective disorder.
Conversion paralysis (CP) is a frequent and impairing psychiatric disorder, affecting voluntary motor function. Yet, we have previously shown that the motor system of CP patients with a unilateral conversion paresis is recruited to a similar degree during imagined movements of the affected and unaffected limb. In contrast, imagery of movements with the affected limb results in larger prefrontal activation.
View Article and Find Full Text PDFIncreasing evidence indicates that eye gaze direction affects the processing of emotional faces in anxious individuals. However, the effects of eye gaze direction on the behavioral responses elicited by emotional faces, such as avoidance behavior, remain largely unexplored. We administered an Approach-Avoidance Task (AAT) in high (HSA) and low socially anxious (LSA) individuals.
View Article and Find Full Text PDFPurpose: Several studies have indicated that psychogenic nonepileptic seizures (PNES) are associated with psychological trauma, but only a few studies have examined the associations with neurobiologic stress systems, such as the hypothalamus-pituitary-adrenal (HPA) axis and its end-product cortisol. We tested several relevant HPA-axis functions in patients with PNES and related them to trauma history.
Methods: Cortisol awakening curve, basal diurnal cortisol, and negative cortisol feedback (using a 1 mg dexamethasone suppression test) were examined in 18 patients with PNES and 19 matched healthy controls (HCs) using saliva cortisol sampling on two consecutive days at 19 time points.
The stress hormone cortisol is important for the regulation of social motivational processes. High cortisol levels have been associated with social fear and avoidance, which play an important role in social anxiety disorder (SAD), as does hypervigilant processing of social threat. However, causal effects of cortisol on threat processing in SAD remain unclear.
View Article and Find Full Text PDFPrevious studies have provided evidence for a vigilant attentional bias toward threat stimuli and increased basal diurnal cortisol levels in patients with psychogenic nonepileptic seizures (PNES). Because cortisol levels may be predictive of threat vigilance, we reanalyzed previous data on threat vigilance in 19 unmedicated patients with PNES and found a positive correlation between baseline cortisol levels and attentional bias scores for threat stimuli (r=0.49, P=0.
View Article and Find Full Text PDFBackground: This study examined differences in sex in collagen regulation during rodent experimental abdominal aortic aneurysm formation.
Methods: Infrarenal aortas of male and female rats were perfused with elastase or saline (control). Aortic diameters were measured at baseline (day 0) and on postoperative days 7 and 14.
Background: Studies on depression have found that childhood abuse (CA) is associated with a persistent sensitization of the hypothalamic-pituitary-adrenal (HPA)-axis to stress in adulthood. So far, it is unknown whether this HPA-axis sensitization is specific to depression, or whether this is a more general outcome associated with CA in patients with mood and anxiety disorders. The aim of this study was to investigate whether CA is associated with enhanced cortisol reactivity to psychosocial stress in Social Anxiety Disorder (SAD).
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