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Pilots are exposed to the "stress of flight" and the chronically activated stress response may play an important role in circulatory system disease progression. We studied the effect of an experimental mental stress on cardiovascular and neuroendocrine activity, in Air Force Academy cadets, before and after one month intensive course.Nine cadets were submitted to a psychometric evaluation before Stroop test (ST), including Minnesota Multiphasic Personality Inventory, State and Trait Anxiety Inventory (STAI X1 and X2 form) and Reaction Scheme Test. After ST, subjects completed a STAI X1 form. Heart rate (HR), systolic and diastolic blood pressure (SBP and DBP) were monitored and serum prolactin (PRL), growth hormone (GH), adrenocorticotropin (ACTH) and cortisol levels were determined, during ST. The protocol was repeated at the end of the course.No significant differences were evident in PRL, GH and ACTH levels. Cortisol concentrations were significantly higher before the course. ST did not modify hormone secretion. ST induced a significant and reproducible elevation of HR and SBP. Basal HR, SBP and DBP values were significantly elevated after the course. Two subjects presented a particular psychometric profile, a different cardiovascular response to ST and did not pass the course.acute mental stress significantly activated cardiovascular response without modifying endocrine responses, in relation to the psychological profiles. A significant increase of cardiovascular parameters was present after the course, with enhanced dichotomy between the endocrine and sympathetic system, suggesting a careful evaluation and follow-up for circulatory system diseases in cadets.

Human beings need to adapt to any extreme, unknown, or isolated environment. This adaptation requires changes in the normal regulation of psychophysiological homeostasis, as described in terms of stress reaction. The aim of the present study was to monitor the processes of human adaptation to cold and isolated areas in Antarctica during the 12th expedition of the Italian National Research Program. Nine healthy subjects (experimental subjects), members of the expedition, and nine controls in Italy, were studied over a period of 2 months. Anterior pituitary hormone secretion, insulin, and melatonin, plus routine blood test, blood pressure, and ECG were performed. In addition, psychophysiological correlates were also recorded before and after the expedition period. In experimental subjects results of metabolic data suggested the presence of an increased peripheral insulin sensitivity at the end of the permanence in the station and a significant increased of total cholesterol. Hematocrite also significantly increased due to the conditions of hypobaric hypoxia. Results of endocrine data showed a significant decrease (p < 0.05) of hormone levels, which was associated with a significant decrement of the Galvanic Skin Response (GSR) activity to a standardized cognitive stress. No significant differences were reported in the controls. The data suggest that the exposure to the extreme environment develops a possible psychophysiological mechanism(s) that decreases the individual arousal.

The complement system consists of several proteins present in human serum interacting among themselves and with the other compounds of the immune system in the host defence process. In particular, late complement component (C5, C6, C7, and C8) deficiencies (LCCD) are closely associated with Neisseria, mainly meningitidis, infections. The aim of our study was to verify this association in an Italian population by analyzing the complement profile in survivors of meningococcal meningitis. Ten out of the 59 (17%) subjects studied had homozygous LCCD (6 C8, 3 C7 and 1 C6). The meningococcal C strain was the most widely diffused (68%) and had infected all homozygous LCCD subjects. In addition meningococcal serogroup C seemed to be the least immunogenic when compared to serogroups A and B. These data confirm the close association between homozygous LCCD and meningococcal infections from common serogroups (A, B and C) in the Italian population. Anti-meningococcal vaccination is usually recommended for LCCD subjects because it increases, both quantitatively and qualitatively, the antibody component of anti-meningococcal immune defence. We therefore analyzed the levels of anti-polysaccharide (PS) A and PSC antibodies in the members of 4 families including normal subjects and subjects with homozygous and heterozygous C7, C8 or factor H defects, before and after vaccination with only PSA+C. Surprisingly, we found the highest levels of antibodies before vaccination in homozygous subjects, followed by heterozygous and normal controls, whereas, after vaccination, homozygous subjects showed the lowest increase of specific antibodies, indicating their relative incapacity to respond to meningococcal PS alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Stressors can induce sizable modifications on immunocompetent cells. Major circulating lymphocyte subsets were quantitated in Italian Air Force student pilots undergoing intensive training and continuous evaluation, a stressful situation both physically and psychologically. Instructor pilots matched for age and assayed in parallel were used as controls. A typical flight training session was not able per se to induce immediate significant modifications of the lymphocyte subset distribution either in the students or instructors, although it did affect plasma levels of stress-related hormones such as growth hormone, prolactin and cortisol in the former. Irrespective of the time of flying, however, the percentage of CD4+ lymphocytes and the CD4/CD8 ratio were lower in students than in instructors, and the absolute number of CD8+ lymphocytes was higher in students than in instructors. In a second series of experiments, 30 student pilots were tested at the beginning and at the end of a flight course (duration 30 days). Although the percentage of CD29+ lymphocytes comprised in the CD8+ subset was reduced at the end of the course in all individuals, such a reduction was more evident in those students who failed to pass the final examination, an additional cause of psychological stress. In light of the functional significance of the lymphocyte subsets investigated, it is suggested that the present stress-induced alterations may have practical implications.

Human immunodeficiency virus (HIV) infection is characterized by a progressive decline in immune functions. The behavior of B-cell clones specifically engaged in the anti-HIV response could play a relevant role in the pathogenesis of such impairment. The spectrotype observed on isoelectric focusing and reverse blotting after antigen challenge is the serum image of antigen-specific B-cell activity and may provide some insight into Ag-dependent B-cell clone recruitment. In this study, we examined the spectrotype of anti-gp120 antibodies in a group of sera from 56 HIV-infected patients, belonging to groups II, III, and IV of the Centers for Disease Control classification, as well as in a group of 31 sera from 12 patients in a 21-month follow-up evaluation (range 7-36 months). All tested sera were positive for gp120 antibodies on Western blot. In the first group of 56 HIV-infected subjects, only 19 displayed well-focused banding patterns. Among these, the spectrotype was found to be consistently oligoclonal, thus confirming clonal restriction of anti-gp120 antibodies previously described by other investigators. No correlation could be established between a particular spectrotype and phase of the disease. The follow-up evaluation in the second group of 31 sera revealed the tendency in each patient to maintain the same spectrotype throughout the course of the disease. These findings confirm clonal restriction of anti-gp120 antibodies in HIV infection and suggest that the number of B-cell clones recruited in the anti-gp120 response remains stable over the course of the disease, at least in the time range explored by us.