Effects of Acute Stress or Centrally Injected Interleukin-1beta on Neuropeptide Expression in the Immune System

Acute stress stimulates the expression and release of corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP) from the hypothalamus, and the pro-opiomelanocortin products beta-endorphin and ACTH from the anterior pituitary. These neuropeptides are also expressed in immune tissues, and it has been proposed that they may modulate immune responses to stress through paracrine mechanisms. We subjected rats to restraint stress or central injection of interleukin (IL)-1beta to determine whether these acute stimuli can alter the expression of neuropeptides in the spleen and thymus. Restraint stress significantly increased the contents of all these neuropeptides in thymic, but not splenic, extracts. A single icv injection of IL-1beta increased contents of CRH, AVP, ACTH and beta-endorphin in the spleens of both sham-operated and adrenalectomised (ADX) rats. IL-1beta increased thymic contents of CRH and ACTH in sham-operated rats but these increases were not observed in ADX rats. These results suggest that the effects of IL-1beta on neuropeptide expression in the spleen are independent of glucocorticoids, whereas IL-1beta stimulation of neuropeptide expression in the thymus is dependent on circulating glucocorticoids. There were significant correlations between increases in CRH, ACTH and beta-endorphin in the spleen, and between CRH and ACTH in the thymus, consistent with the suggestion that IL-1beta-induced increases in ACTH and beta-endorphin may be mediated through CRH. These results provide evidence that stressors can directly influence neuropeptide expression in immune tissues. Thus stress may influence immune functions through paracrine mechanisms involving locally synthesised neuropeptides as well as through activation of the hypothalamo-pituitary-adrenal axis.     

The transfer of respondent eliciting and extinction functions through stimulus equivalence classes

Two studies investigated the transfer of respondent elicitation through equivalence classes. In Experiment 1, match-to-sample procedures were used to teach 8 subjects two four-member equivalence classes. One member of one class was then paired with electric shock, and one member of the other class was presented without shock. All remaining stimuli were then presented. Using skin conductance as the measure of conditioning, transfer of conditioning was demonstrated in 6 of the 8 subjects. In Experiment 2, similar procedures were used to replicate the results of Experiment 1 and investigate the transfer of extinction. Following equivalence training and conditioning to all members of one class, one member was then presented in extinction. When the remaining stimuli from this class were then presented, they failed to elicit skin conductance. In the final phase of the experiment, the stimulus that was previously presented in extinction was reconditioned. Test trials with other members of the class revealed that they regained elicitation function. These results demonstrate that both respondent elicitation and extinction can transfer through stimulus classes. The clinical and applied significance of the results is discussed.     

Employment status and the attitudes and behavior of higher status women volunteers, 1975 and 1992: A case study

This study examines the relationships between employment status and women's attitudes toward and participation in a higher status voluntary service organization. Data were gathered in 1975 and 1992 from a sample of chapters of the International Association of Women (a pseudonym). The 1992 sample included three percent who reported a racial or ethnic identification other than white. Drawing on several theoretical perspectives, we expected to find differences in the attitudes and level of participation of employed versus non-employed members that would have important effects on organizational functioning. However, few differences in the attitudes of members employed full time, part time, and not in the labor force were found in either 1975 or 1992. There were, however, differences in behavior. Employed members reported spending much less time on organizational activities and were less likely to assume leadership roles, but these differences diminished between 1975 and 1992 as employed women became numerically dominant in the organization, suggesting that the growing presence of employed women in IAW led to the development of informal norms and new policies about the amount of time members should devote to the organization and a corresponding loss in the total number of volunteer hours devoted to it.     

I can be a bum: Knowledge about abilities and life style in vocational behavior

From recent reviews of the vocational behavior literature, it is suggested that vocational theory and research need to move toward models which take seriously the problems generated by normative theories. Such a model is presented which uses a cognitive model of behavior and incorporates life style parameters. The research implications of the model are outlined.     

Theories as recipes: third-order virtue and vice

Philosophical Studies - A basic way of evaluating metaphysical theories is to ask whether they give satisfying (not necessarily truthful!) answers to the questions they set out to resolve. I...     

McColl and Minimization

In 1952, Quine showed that the problem of reducing a propositional formula to a simplest normal equivalent can be solved in two steps, viz., (i) express the given formula, Φ, equivalently as the disjunction of all its prime implicants, and (ii) find all non-redundant disjunctions of the latter that are equivalent to Φ (Quine 1952 Quine, W. V. 1952. ‘The problem of simplifying truth functions’. American Mathematical Monthly, 59: 521–531. [Taylor &; Francis Online] , [Google Scholar]). However, it seems not generally known that an ingenious form of the same two-step process was published by Hugh McColl in 1878.     

Following logical realism where it leads

Philosophical Studies - Logical realism is the view that there is logical structure in the world. I argue that, if logical realism is true, then we are deeply ignorant of that logical structure:...     

Cognitive and attentional functioning in adolescents and young adults with Tetralogy of Fallot and d-transposition of the great arteries

The objective of this study is to investigate cognitive and attentional function in adolescents and young adults with operated congenital heart disease. Previous research has indicated that children with congenital heart disease have deficits in broad areas of cognitive function. However, less attention has been given to survivors as they grow into adolescence and early adulthood. The participants were 18 non-syndromic adolescents and young adults with tetralogy of Fallot and d-transposition of the great arteries that required cardiac surgery before the age of 5 years, and 18 healthy, unaffected siblings (11–22 years of age for both groups). Cases with congenital heart disease and their siblings were administered Wechsler Intelligence scales and reported attention problems using the Achenbach System of Empirically Based Assessments. Cases were compared to both healthy siblings and established norms. Cases performed significantly lower than siblings on full scale IQ and processing speed, and significantly lower than norms on perceptual reasoning. Cases also reported more attention problems compared to both siblings and norms. Effect sizes varied with medium-to-large effects for processing speed, perceptual reasoning, working memory, and attention problems. Findings suggest that neurocognitive function may continue to be affected for congenital heart disease survivors in adolescence and young adulthood, and that comparisons to established norms may underestimate neurocognitive vulnerabilities.