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Prolactin (PRL) has been reported to inhibit apoptosis in various cell types and to serve as a cofactor in the upregulation of CD25 on T cells during activation. We investigated a possible relation between prolactin receptor (PRL-R) or IL-2 receptor alpha (IL-2Ralpha, CD25) expression on circulating T lymphocytes and their apoptosis in patients with breast cancer. Peripheral blood mononuclear cells obtained from 25 patients, 25 normal controls (NC) and three cord blood samples were evaluated for Annexin V binding and expression of CD95, CD25, and PRL-R on CD3(+) T cells by multicolour flow cytometry. Plasma levels of PRL, sCD95L, and sIL-2R were determined in patients and controls and related to T-cell apoptosis. The ability of PRL to protect T cells from apoptosis induced by various agents was also studied. Expression of PRL-R on the surface of T cells was comparable in patients with breast cancer and NC, but PRL plasma levels in patients were significantly lower (P<0.05). In patients, 18+/-11% (mean+/-s.d.) of CD3(+) cells bound Annexin V, compared to 9+/-6% in NC (P<0.0004). Percentages of CD3(+)Fas(+) and CD3(+)CD25(+) cells were higher in the peripheral circulation of patients than NC (P<0.0001 and <0.04, respectively). Levels of sFasL were lowest in plasma of the patients with the highest proportions of CD3(+)Fas(+) T cells. Most T cells undergoing apoptosis were CD3(+)CD25(-) in patients, and the proportion of CD3(+)CD25(-) Annexin V(+) cells was significantly increased in patients compared to NC (P<0.006). Ex vivo PRL protected T cells from starvation-induced or anti-CD3Ab-induced but not from Fas/FasL-dependent apoptosis. These results indicate that expression of CD25 but not of PRL-R on the surface of activated T lymphocytes appears to be involved in modulating Fas/Fas - ligand interactions, which are, in part, responsible for apoptosis of T lymphocytes and excessive turnover of immune cells in the circulation of patients with breast cancer.

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BACKGROUND: This investigation examined the relationship between trauma, psychiatric symptoms and urinary free cortisol (UFC) and catecholamine (epinephrine [EPI], norepinephrine [NE], dopamine [DA]) excretion in prepubertal children with posttraumatic stress disorder (PTSD) secondary to past child maltreatment experiences (n = 18), compared to non-traumatized children with overanxious disorder (OAD) (n = 10) and healthy controls (n = 24). METHODS: Subjects underwent comprehensive psychiatric and clinical assessments and 24 hour urine collection for measurements of UFC and urinary catecholamine excretion. Biological and clinical measures were compared using analyses of variance. RESULTS: Maltreated subjects with PTSD excreted significantly greater concentrations of urinary DA and NE over 24 hours than OAD and control subjects and greater concentrations of 24 hour UFC than control subjects. Post hoc analysis revealed that maltreated subjects with PTSD excreted significantly greater concentrations of urinary EPI than OAD subjects. Childhood PTSD was associated with greater co-morbid psychopathology including depressive and dissociative symptoms, lower global assessment of functioning, and increased incidents of lifetime suicidal ideation and attempts. Urinary catecholamine and UFC concentrations showed positive correlations with duration of the PTSD trauma and severity of PTSD symptoms. CONCLUSIONS: These data suggest that maltreatment experiences are associated with alterations of biological stress systems in maltreated children with PTSD. An improved psychobiological understanding of trauma in childhood may eventually lead to better treatments of childhood PTSD.

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OBJECTIVE: The present study evaluated whether chronic stress levels moderated the impact of laboratory stressors on subjective and behavioral responses to alcohol. METHOD: Healthy volunteers (N = 60; 30 male) completed measures of background stress levels (e.g., major life events). In addition, subjects were exposed to two laboratory stressors (i.e., cold pressor or film stressor task) or a control condition after consuming a 0.7 g/kg dose of alcohol. RESULTS: Regression analyses showed that the combination of high background stress levels and exposure to a lab stressor reduced two measures of perceived intoxication (i.e., Sensation Scale, Visual Analog Intoxication Scale). CONCLUSIONS: These data are consistent with a biobehavioral model of alcohol use where acute and chronic stressors are associated with a diminished response to alcohol. The possible mechanisms that may underlie this sobering effect include stress-related cognitive deficits and situation specific tolerance associated with high chronic stress levels.

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The human operator of slow, multivariate processes has a task which involves continuous decision making in real time. This paper evaluates the techniques available for analysis of such situations and gives an example of an application in the glass industry. Field analysis techniques and results are compared with laboratory experiments to list factors which have been shown to affect overall operator/process performance.