In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

Context: Optimistic people report a higher quality of life, engage in more active coping and adopt more health-promoting behaviors than people low in optimism, ie, pessimism. We evaluated whether pessimists are more likely to show progression in carotid disease than optimists.', 'A total of 209 middle-aged healthy premenopausal women enrolled in an epidemiological study of cardiovascular risk factors and had carotid scans 10.4 years and 13.5 years later when they were at least 5 years postmenopausal. Women completed the Life Orientation Test (LOT), a measure of pessimistic and optimistic attitudes, at study entry and at the time of the first carotid scan. Analyses evaluated the association of LOT scores and change in carotid intima medial thickness (IMT) across 3 years.', 'Multiple linear regression analyses showed that the higher the pessimism scores at study entry, the greater the increase in mean IMT (beta = 0.17, p <.007). A comparison of those in the lowest quartile of LOT scores (most optimistic) with those in the other three quartiles showed that the most optimistic group had less progression than the remaining more pessimistic women (mean percent increase = 1.3 and 6.0 for mean IMT, F = 15.4, p <.001). Women who were chronically optimistic at study entry and at the first carotid scan (bottom quartiles at both times) had less progression in mean IMT than did those who were chronically pessimistic (top quartiles at both times).\Question: Do optimistic attitudes protect against progression of carotid atherosclerosis in healthy middle-aged women?
Optimistic women are less likely to show progression of carotid disease in mid-life than are pessimists.

Context: To compare rates of undertriage and overtriage of six ambulance dispatch protocols for the presenting complaint of nontraumatic abdominal pain, and to identify the optimal protocol.', 'Retrospective prehospital and emergency department chart review to classify patients' conditions as "emergency" or "nonemergency." Utility analysis was used to identify the preferred protocol and monetary cost-effectiveness analysis to identify the least expensive protocol.', 'County emergency medical services (EMS) system with five receiving hospitals serving a mainly urban population of approximately 350,000.', 'Records of 902 patients who called 911 for nontraumatic abdominal pain were reviewed; patients not transported were excluded. Twenty-seven county EMS medical directors completed questionnaires.', 'Six ambulance dispatch protocols for nontraumatic abdominal pain were developed: indiscriminate-dispatch, four selective protocols, and no-dispatch. A dichotomous classification system was derived prospectively from the prehospital and medical records of patients who had activated the EMS system before the study period to define "emergency" and "nonemergency" conditions associated with nontraumatic abdominal pain. Emergency criteria identified patients with conditions requiring medical treatment within 1 hour. Reviewers determined, for each patient, whether an ambulance would have been dispatched by each of the protocols. Undertriage and overtriage rates were calculated for each protocol. County EMS medical directors assigned utility values to four potential outcomes of ambulance dispatch by the direct scaling method. The outcomes comprised correct and incorrect decisions to dispatch ambulances to patients with and without emergencies. The protocols were compared by decision analysis. A cost analysis was also performed, using an estimated marginal cost per transport of $302. Sensitivity analysis demonstrated the effect of varying the cost of an undertriage error and the cost per response. Of the 788 patients included in the study, 7.8% had conditions defined as emergencies. The four selective ambulance dispatch protocols had overtriage rates ranging from 10% to 51% and undertriage rates of 4% to 7%. None of the protocols was proven superior on the basis of the medical directors' assignment of utility values. The marginal cost of dispatching advanced life support ambulances to all patients with this complaint was $3,838 per emergency.\Question: Do comparison of ambulance dispatch protocols for nontraumatic abdominal pain?
The majority of patients with nontraumatic abdominal pain who requested ambulance transport during the study period did not have conditions that were classified as emergencies. In the study model, if an undertriage error costs more than $3,674, indiscriminate ambulance dispatch is the least expensive protocol, and if an undertriage error costs less than $3,674, no ambulance dispatch is the least expensive strategy.

Context: To define whether immunosuppressive agents that block the interleukin (IL)-2 pathway could prevent activation-induced cell death of activated T cells in the graft, we measured expression of IL-2, IL-2 receptor alpha chain (CD25), IL-15, Fas, and Fas ligand by real time reverse transcription-polymerase chain reaction in cardiac allografts.', 'We characterized the phenotype of the infiltrating cells (CD3, CD68, CD25) by immunohistochemistry. The proportion of apoptotic graft-infiltrating cells was determined by TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling) staining. We analyzed endomyocardial biopsy specimens from cardiac allograft recipients who were treated with anti-CD25 monoclonal antibody (mAb) induction therapy (daclizumab) or with matching placebo in combination with cyclosporine, steroids, and mycophenolate mofetil.', 'Treatment with anti-CD25 mAb affected the number of infiltrating CD3 and CD68 cells and the IL-2-regulated apoptotic pathway. During anti-CD25 mAb treatment, significantly lower intragraft IL-2 and CD25 mRNA transcription levels and decreased numbers of CD25+ T cells were found compared with the levels measured in endomyocardial biopsy specimens from placebo-treated patients (5- to 10-fold, P=0.002 and P<0.0001, respectively). In these samples the intragraft mRNA expression levels of IL-15 were also lower (P=0.02). Inhibition of the IL-2 pathway by anti-CD25 mAb therapy was accompanied by reduced mRNA and protein of Fas ligand and not by reduced Fas expression (P=0.001 and P=0.03). TUNEL staining revealed that the proportion of graft-infiltrating cells was lower in the anti-CD25 mAb patient group than the proportion of apoptotic cells in patients receiving placebo (P=0.06).\Question: Does anti-CD25 monoclonal antibody therapy affect the death signals of graft-infiltrating cells after clinical heart transplantation?
Our data suggest that immunosuppressive agents that affect the IL-2 pathway hinder the mechanism of activation-induced cell death by which the immune system eliminates alloreactive cells.