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: After ingestion of phosphatidylcholine, l-carnitine or betaine, trimethylamine-N-oxide (TMAO) is formed by gut microbiota and liver enzymes. Elevated TMAO plasma levels were associated with increased cardiovascular risk and other diseases. Also betaine and choline itself were recently associated with increased cardiovascular risk.', 'A newly developed LC-HRMS method was applied to measure the plasma concentrations of TMAO, betaine and choline in a cohort of 339 patients undergoing coronary angiography for the evaluation of suspected coronary artery disease.', "Betaine concentrations in males were significantly higher than in females (42.0 vs. 35.9\xa0μmol/L; p\xa0<\xa00.001). Plasma concentrations of TMAO but not of betaine or choline were higher in patients with diabetes compared to euglycemic patients (2.39 vs. 0.980\xa0μmol/L; p\xa0=\xa00.001) as well as in patients with metabolic syndrome as compared to patients without metabolic syndrome (2.37 vs. 1.43\xa0μmol/L; p\xa0=\xa00.002). Plasma concentrations of TMAO or choline increased significantly with decreasing renal function (Spearman's rho:\xa0-0.281; p\xa0<\xa00.001). However, plasma levels of TMAO or betaine were associated with neither a history of myocardial infarction nor the angiographically assessed presence of coronary heart disease, nor incident cardiovascular events during 8 years of follow-up. Plasma levels of choline were significantly lower in patients with a history of acute myocardial infarction as compared to those without such history (10.0 vs. 10.8\xa0μmol/L; p\xa0=\xa00.045).
Answer: Plasma levels of TMAO are confounded by impaired kidney function and poor metabolic control but are not associated with the history, presence or incidence of symptoms or events of coronary heart disease.

A: Are plasma levels of trimethylamine-N-oxide confounded by impaired kidney function and poor metabolic control?
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Q: Context: Accumulating evidence suggests that the balance between pathogenic effector T cells (Teffs) and regulatory T cells (Tregs) may be important for controlling atherosclerotic disease. We hypothesized that a combination therapy with anti-CD3 antibody (CD3-Ab) and IL-2/anti-IL-2 monoclonal antibody complex (IL-2 complex) aimed at increasing the ratio of Tregs to Teffs would effectively inhibit atherosclerosis in mice.', 'We treated apolipoprotein E-deficient mice fed a high-cholesterol diet with vehicle, CD3-Ab, IL-2 complex, or their combination. Mice receiving the combination therapy had markedly reduced atherosclerotic lesions than mice treated with CD3-Ab or IL-2 complex alone. In addition, a striking increase in the Treg/Teff ratio of lymphoid organs and atherosclerotic lesions, along with plaque stabilization characterized by decreased macrophage content and increased collagen content was observed. The combination treatment also markedly reduced splenic Ly6C(high) inflammatory monocytes and might induce a favorable macrophage phenotype change in atherosclerotic lesions.
Answer: Our results indicate that in addition to suppressing Teff responses, enhancing Treg-mediated immune responses is more efficacious in preventing atherosclerosis, suggesting a novel therapeutic approach for atherosclerosis.

A: Does cD3 antibody and IL-2 complex combination therapy inhibit atherosclerosis by augmenting a regulatory immune response?
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Q: Context: Septic hip revisions are associated with greater complications and higher costs than aseptic revisions. It is unclear whether blood loss and transfusion requirements are different in septic and aseptic revisions. We hypothesized that the blood loss and transfusion are dependent on the complexity of the revision surgery and patient's general health rather than the presence of infection.", 'We retrospectively reviewed 626 revision total hip arthroplasties in 547 patients between 2009 and 2013. All the procedures were classified as septic (n\xa0= 120) or aseptic (n\xa0= 506) based on the Musculoskeletal Infection Society criteria for periprosthetic joint infection. Independent risk factors for transfusion and blood loss were analyzed using a multiple regression analysis.', 'The transfusion rate was higher in septic revisions (septic\xa0= 108/120 [90%], aseptic\xa0= 370/506 [73%]; P < .001), so was the average amount of blood loss (septic\xa0= 2533 ± 161 mL, aseptic\xa0= 1974 ± 68 mL; P < .001). After adjusting for potential confounders, infection was not an independent risk factor for transfusion (P = .176) or blood loss (P = .437). Increasing age (P = .004), higher American Society of Anesthesiologists score (P = .047), lower preoperative hemoglobin (P < .001), cell saver use (P < .001), and complex revision surgery (P < .001) were independently associated with greater risk of transfusion.
Answer: Although blood loss and transfusion rates were higher in septic revisions, the presence of infection alone did not increase the risk of transfusion or blood loss. Blood management strategies in revision total hip arthroplasties should be guided by the type of surgery planned and patient's preoperative health rather than the presence of infection.

A:
Is infection a Risk Factor for Perioperative and Postoperative Blood Loss and Transfusion in Revision Total Hip Arthroplasty?
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