instruction:
Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
question:
Context: Differences in mortality are thought to exist between African Americans and Caucasians with heart failure. These differences may be due to a variety of factors, including differences in disease process, socioeconomic status, and access to health care. Additionally, little data exist on racial differences between these two groups after cardiac transplantation. This study examines a single center, urban experience in treating African Americans and Caucasians with heart failure and after cardiac transplantation. We hypothesize that treatment in a specialized, comprehensive heart failure/cardiac transplantation program results in similar survival between African Americans and Caucasians.', 'We retrospectively reviewed the Rush Heart Failure and Cardiac Transplant Database from July 1994 to August 2000. Variables analyzed in the cardiomyopathy patients included survival (until death, placement of left ventricular assist device or cardiac transplantation), number of hospitalizations per year, length of stay per year, and utilization of outpatient resources. Follow-up period was from initial visit to death, transplantation, or implantation of left ventricular assist device. In those who underwent cardiac transplantation, we examined rejection rates (cellular and humoral), rejection burden, hospitalization data, and 5-year survival. A subgroup bridged to cardiac transplantation with a left ventricular device was also analyzed.', 'Seven hundred thirty-four cardiomyopathy patients were identified: 203 were African Americans and 531 were Caucasians. The etiology of cardiomyopathy was more commonly ischemic in Caucasians as compared to non-ischemic in African Americans (P <.01). African Americans had more admissions to the hospital per year compared with Caucasians, 1.2 +/- 2.1 versus.5 +/- 1.1 (P <.01) with longer length of stay per year, 1.4 +/- 25.2 days versus 4.4 +/- 14.3 days (P <.01). Utilization of outpatient resources was significantly higher in African Americans compared with Caucasians with more use of continuous inotropes (13% versus 6%, P <.01), intermittent inotropes (11% versus 5%, P <.01), and home nursing after hospital discharge (52% versus 32% of hospital discharges, P <.01). Survival by Kaplan-Meier analysis was comparable between the two groups (mean survival 1,470 +/- 72 days in African Americans versus 1521 +/- 46 days in Caucasians, log rank test [P =.6]). During this time, 30 African Americans and 73 Caucasians underwent cardiac transplantation. Fifty-three were bridged to transplantation with a left ventricular assist device (20 African Americans, 33 Caucasians). There were no differences in 5-year survival by Kaplan-Meier analysis despite higher peak preoperative panel reactive antibody levels in African Americans versus Caucasians (12% +/- 30% compared with 5% +/- 15%, P =.04), more overall treated rejection episodes per year in the African Americans (P <.01), as well as more posttransplant hospitalizations (2.2 +/- 1.2 times per year as compared with 1.7 +/- 2.1 times per year, P =.04).
Answer: Delivery of care to heart failure patients in a comprehensive, specialized program results in similar survival regardless of race despite higher utilization of inpatient and outpatient resources. The finding that, after cardiac transplantation, African Americans do not have higher mortality rates, despite having higher rates of rejection overall and more hospitalizations, further supports the hypothesis that optimal care can improve outcomes despite unfavorable baseline clinical characteristics.
answer:
Are influence of race in heart failure and cardiac transplantation : mortality differences eliminated by specialized , comprehensive care?


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Context: It is well established that African Americans (AA) experience greater pain associated with a variety of clinical conditions, and greater pain sensitivity to experimental pain tasks relative to non-Hispanic Whites (W). Notably, African Americans do not show the same relationships involving endogenous pain regulatory mechanisms and pain sensitivity documented in Caucasians, including positive associations between blood pressure, norepinephrine, cortisol and greater pain tolerance.', 'The purpose of this study was to examine the relationship between plasma oxytocin (OT) and pain sensitivity and to explore the relation of OT to other factors known to influence pain perception.', 'OT concentration and sensitivity to ischemic, cold pressor, and thermal pain tasks were assessed in African American (n=25) and non-Hispanic White (n=23) pre-menopausal women.', 'African American women demonstrated significantly lower pain tolerance across tasks compared with Whites (F(1,46)=6.31, p=0.0156) and also exhibited lower plasma OT levels (AA: 3.90, W: 7.05 pg/mL; p=0.0014). Greater OT levels were correlated with greater tolerance to ischemic pain (r=0.36, p=0.013) and accounted for a marginally significant portion of the ethnic difference in ischemic pain tolerance (B=+0.29, p=0.06). Greater OT was also correlated with greater tolerance of cold pressor pain (r=0.31, p=0.03); however, this association was no longer seen after the variance due to ethnicity was accounted for.
Answer: These data suggest that reduced oxytocinergic function may be one of multiple biological factors contributing to the greater sensitivity to experimental ischemic pain, and to the greater burden of some types of clinical pain experienced by African Americans compared with Whites.
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Is ethnicity associated with alterations in oxytocin relationships to pain sensitivity in women?


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Context: The Duffy blood group (Fy) antigen functions as the receptor whereby the malarial parasite Plasmodium vivax invades reticulocytes. In this study, we evaluated an autologous blood donation model to measure Fy expression during the anticipated response to blood loss.', 'This study aims to examine Fy expression following anticipated reticulocytosis in response to blood loss from autologous whole blood donation.', 'Subjects were healthy blood donors presenting for planned collection of two or three autologous units. Whole blood (450 ml +/- 10%) was collected and processed. Blood samples for Fy testing were obtained from the donations. These were assayed by flow cytometry by measuring binding of a phycoerythrin-labelled anti-Fy6 antibody and compared against reticulocyte numbers. Reticulocyte numbers were measured using thiazole orange. Results were compared from baseline (first donation) with samples at second and, if available, third, donations. Phenotyping for Fy a and b antigens was performed.', 'Reticulocytes increased by a mean of 37% over baseline [0.93% (range 0.31-1.93) to 1.23% (0.32-3.51%)] following donation of two (n = 32) or three (n = 9) autologous whole blood units. Absolute reticulocyte count remained low. Mean and median Fy expression on mature red blood cells and reticulocytes did not change from baseline levels despite individual variation. No apparent relationship to serologically determined Fy a and/or b antigen status was present.
Answer: Baseline expression of Fy antigen on mature red blood cells and reticulocytes is quite variable between individuals, but appears not to be greatly affected by mild to moderate reticulocytosis following blood loss in an autologous blood donation model.
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Does duffy antigen expression on reticulocytes alter following blood loss in an autologous donation model?