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.

Q: Context: A number of risk factors for chronic renal allograft rejection have been identified; in particular the number and severity of acute rejections, hypertension, hyperlipidemia, and insufficient immunosuppression.', 'In a retrospective case control study, all histologically confirmed cases of chronic rejection (n=45) that occurred between 1985 and 1993 among patients transplanted at Huddinge Hospital were compared with twice as many controls. Determinants such as donor age and sex, HLA-mismatch, cold ischemia time, recipient age and sex, body mass index, cause of renal disease, time undergoing dialysis, condition of blood vessels at surgery, time of onset, number of acute rejection episodes during the first 3 months, area under the serum creatinine versus time curve (AUC(Creatinine)), blood pressure, blood lipids, and cyclosporine concentrations at various times after the transplantation were also compared. Additional data were obtained from a questionnaire, concerning 79% of the cases and controls.', 'Cases and controls were similar with regard to most determinants, that is, blood pressure, blood lipids, and average cyclosporine concentrations. The main outstanding risk factor for chronic rejection was the time-averaged creatinine (AUC(Creatinine)) value between day 22 and 3 months after transplantation. The adjusted odds ratio for chronic rejection increased stepwise from 1.1 to 9.2, when AUC(Creatinine) increased from < 150 to >300 micromol/l. The number of acute rejection episodes and number of HLA-mismatches also had a significant effect on the risk of chronic rejection.
Answer: To reduce the risk of developing chronic rejection after renal transplantation acute rejection episodes during the first 3 months should be avoided as much as possible.

A: Is area under the serum creatinine time-curve a strong predictor of chronic renal allograft rejection?
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Q: 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.

A: Is ethnicity associated with alterations in oxytocin relationships to pain sensitivity in women?
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Q: Context: The chronic inflammation plays an important role in heart failure and complement components might be useful markers of the prognosis. We set out to evaluate their predictive value in the clinical outcomes of patients with cardiac resynchronization therapy (CRT).', 'We determined the complement levels C3, C3a, sC5b-9 and also the N-terminus of the prohormone brain natriuretic peptide (NT-proBNP) of 126 heart failure patients in a prospective, single-center observational study before and 6\xa0months after CRT implantation.', 'CRT reduced the C3a [212.5 (148.2-283.6) vs. 153 (119.8-218.3)\xa0ng/mL, p\xa0<\xa00.0001] and the sC5b-9 levels [296.9 (234.2-358.8) vs. 255.1 (210.1-319.0)\xa0ng/mL, p\xa0=\xa00.0006], but not the total C3 levels [1.43 (1.26-1.61) vs. 1.38 (1.23-1.57) g/L, p\xa0=\xa00.57]. C3a predicted the 5-year mortality of the patients [C3a\xa0>\xa0165\xa0ng/mL hazard ratio\xa0=\xa04.21 (1.65-10.72), p\xa0=\xa00.003] independent of the NT-proBNP and other factors. After reclassification, we observed a significant net reclassification improvement [NRI\xa0=\xa00.71 (0.43-0.98), p\xa0<\xa00.0001] and integrated discrimination improvement [IDI\xa0=\xa00.08 (0.03-0.12), p\xa0=\xa00.0002].
Answer: In patients with CRT, elevated C3a levels increase the risk of mortality independent of the NT-proBNP levels or other factors. CRT exerts anti-inflammatory effect by reducing the complement activation.

A:
Does complement C3a predict outcome in cardiac resynchronization therapy of heart failure?
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