Disordered eating behaviour is associated with blunted cortisol and cardiovascular reactions to acute psychological stress

Research suggests a potential dysregulation of the stress response in individuals with bulimia nervosa. This study measured both cardiovascular and cortisol reactions to a standardised laboratory stress task in individuals identified as showing disordered eating behaviour to determine whether dysregulation of the stress response is characteristic of the two branches of the stress response system. Female students (N = 455) were screened using two validated eating disorder questionnaires. Twelve women with disordered eating, including self-induced vomiting, and 12 healthy controls were selected for laboratory stress testing. Salivary cortisol and cardiovascular activity, via Doppler imaging and semi-automatic blood pressure monitoring, were measured at resting baseline and during and after exposure to a 10-min mental arithmetic stress task. Compared to controls the disordered eating group showed blunted cortisol, cardiac output, heart rate, and stroke volume reactions to the acute stress, as well as an attenuated vasodilatory reaction. These effects could not be accounted for in terms of group differences in stress task performance, subjective task impact/engagement, age, BMI, neuroticism, cardiorespiratory fitness, or co-morbid exercise dependence. Our findings suggest that disordered eating is characterised by a dysregulation of the autonomic stress-response system. As such, they add further weight to the general contention that blunted stress reactivity is characteristic of a number of maladaptive behaviours and states

Cardiovascular and cortisol reactions to acute psychological stress and cognitive ability in the Dutch Famine Birth Cohort Study

Objective: Recently, in analyses of data from a large community sample, negative cross-sectional and prospective associations between cardiac stress reactivity and obesity were observed. The present study re-examined the association between cardiovascular reactivity and adiposity in the Dutch Famine Birth Cohort, with the additional aim of examining the association between cortisol reactivity and adiposity. Methods: Blood pressure, heart rate, and salivary cortisol were measured at rest and in response to standard laboratory stress tasks in 725 adults. Height, weight, waist and hip circumference, and skin fold thickness were measured. Four to seven years later 460 participants reported current height and weight. Obesity was defined as a BMI > 30kg/m2. Results: Cross-sectional analyses revealed negative associations between all measures of adiposity and heart rate reactivity; those with a greater BMI (ß = -0.39 bpm), waist-hip ratio (ß = -0.15 bpm), and triceps and subscapular skin fold thicknesses (ß = -1.0 bpm and -1.8 bpm), or categorized as obese (-3.9 bpm) displayed smaller cardiac reactions to acute stress (all p <.001). With the exception of waist-hip ratio, the same negative associations emerged for cortisol reactivity (all p ≤ .01). In prospective analyses, low cardiac reactivity was associated with an increased likelihood of becoming or remaining obese in the subsequent 4-7 years (OR 1.03, p = .01). All associations withstood adjustment for a range of possible confounders. Conclusions: The present analyses provide additional support for the hypothesis that it is low not high cardiac and cortisol stress reactivity that is related to adiposity

The role of emotions and physiological arousal in modulating impulsive behaviour.

Impulsivity received considerable attention in the context of drug misuse and certain neuropsychiatric conditions. Because of its great health and well-being importance, it is crucial to understand factors which modulate impulsive behaviour. As a growing body of literature indicates the role of emotional and physiological states in guiding our actions and decisions, we argue that current affective state and physiological arousal exert a significant influence on behavioural impulsivity. As 'impulsivity' is a heterogeneous concept, in this paper, we review key theories of the topic and summarise information about distinct impulsivity subtypes and their methods of assessment, pointing out to the differences between the various components of the construct. Moreover, we review existing literature on the relationship between emotional states, arousal and impulsive behaviour and suggest directions for future research

Far-infrared loops in the 2nd Galactic Quadrant

We present the results of an investigation of the large scale structure of the diffuse interstellar medium in the 2nd Galactic Quadrant (90 <= l <= 180). 145 loops were identified on IRAS based far-infrared maps. Our catalogue lists their basic physical properties. The distribution clearly suggests that there is an efficient process that can generate loop-like features at high galactic latitudes. Distances are provided for 30 loops. We also give an observational estimate on the volume filling factor of the hot gas in the Local Arm, 4.6% <= f_2nd <= 6.4%Comment: accepted for publication in Astronomy & Astrophysics Fig. 2, Appendix A, B and C are available at http://astro.elte.hu/CFIRL

Identification of CD8+ T Cell Epitopes in the West Nile Virus Polyprotein by Reverse-Immunology Using NetCTL

West Nile virus (WNV) is a growing threat to public health and a greater understanding of the immune response raised against WNV is important for the development of prophylactic and therapeutic strategies.In a reverse-immunology approach, we used bioinformatics methods to predict WNV-specific CD8(+) T cell epitopes and selected a set of peptides that constitutes maximum coverage of 20 fully-sequenced WNV strains. We then tested these putative epitopes for cellular reactivity in a cohort of WNV-infected patients. We identified 26 new CD8(+) T cell epitopes, which we propose are restricted by 11 different HLA class I alleles. Aiming for optimal coverage of human populations, we suggest that 11 of these new WNV epitopes would be sufficient to cover from 48% to 93% of ethnic populations in various areas of the World.The 26 identified CD8(+) T cell epitopes contribute to our knowledge of the immune response against WNV infection and greatly extend the list of known WNV CD8(+) T cell epitopes. A polytope incorporating these and other epitopes could possibly serve as the basis for a WNV vaccine