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.

Input: Consider Input: Context: To investigate the significance of respiratory muscle weakness in chronic heart failure and its relation both to maximum oxygen consumption during cardiopulmonary exercise testing and to skeletal muscle (quadriceps) strength.', 'Seven healthy men aged 54.9 (SEM 4.3) years and 20 men with chronic heart failure aged 61.4 (1.6) years (P = 0.20) with radionuclide left ventricular ejection fraction of 25.4 (3.0)%.', 'Mouth pressures during maximum static inspiratory effort (PImax) at functional residual capacity (FRC) and residual volume (RV) were measured in all subjects and taken as indices of inspiratory muscle strength. Similarly, mouth pressures during maximum static expiratory effort (PEmax) at FRC and total lung capacity (TLC) were taken as indices of expiratory muscle strength. Cardiopulmonary exercise testing was performed in all subjects. All controls and 15 heart failure patients also had their right quadriceps muscle strength measured.', 'There was respiratory muscle weakness in heart failure patients, with reduction of PImax at FRC (59.7) (6.3) v 85.6 (9.6) cm H2O, P = 0.045), PEmax at FRC (94.8 (6.2) v 134.6 (9.1) cm H2O, P = 0.004), and PEmax at TLC (121.7 (8.5) v 160.7 (13) cm H2O, P = 0.028). PImax at RV was also reduced but this did not reach statistical significance (77.3 (6.6) v 89.3 (13) cm H2O, P = 0.44). There was also significant weakness of the right quadriceps muscle (308.5 (22) v 446.2 (28) N, P = 0.001). PImax at both FRC and RV correlated with maximum oxygen consumption (r = 0.59, P = 0.006, and r = 0.45, P = 0.048 respectively) but not PEmax. There was, however, no significant correlation between PImax and right quadriceps strength.
Answer: Respiratory muscle weakness is seen in chronic heart failure. The results suggest that inspiratory muscles are important in determining maximum oxygen consumption and exercise tolerance in these patients. The lack of correlation between respiratory and right quadriceps muscle strength further suggests that the magnitude and time course of respiratory and locomotor muscle weakness may differ in individual patients. Treatment aimed at improving the function of the involved muscle groups may alleviate symptoms.

Output: Is inspiratory muscle strength a determinant of maximum oxygen consumption in chronic heart failure?


Input: Consider Input: Context: This study evaluated risk factors for acute wheeze in preschool children and investigated whether subnormal levels of vitamin D were associated with increased risk for acute wheeze, atopy or viral/bacterial respiratory infections.', 'We recruited 130 children with acute wheeze, aged 6\xa0months to 4\xa0years, from paediatric emergency departments in Stockholm, Sweden, and 101 age-matched controls with no history of wheeze or sensitisation to airborne allergens. Parents answered standardised questionnaires, and blood samples were analysed for specific IgE to airborne and food allergens and levels of 25 hydroxyvitamin D (25(OH)D). Nasopharyngeal virus samples were collected during the emergency department visit in the group of children with wheeze, and a subset were also tested for bacteria.', 'Vitamin D insufficiency (25(OH)D\xa0<\xa075\xa0nmol/L (30\xa0ng/mL)) was associated with an odds ratio of 2.7 (95% confidence interval 1.1-6.2) for acute wheeze. However, no association was found between vitamin D insufficiency and atopy, presence of virus or bacteria or recurrent infections. Children older than 24\xa0months were particularly at risk of subnormal vitamin D levels, irrespective of wheezing history.
Answer: Our findings support the hypothesis that subnormal levels of vitamin D are associated with acute wheeze in young children.

Output: Are subnormal levels of vitamin D associated with acute wheeze in young children?


Input: Consider Input: Context: Approximately 12% of bound blood calcium is linked to various anions including phosphate. In patients with end-stage kidney disease (ESKD), serum phosphate is highly variable. We propose that establishing a formula to calculate albumin- and phosphate-corrected total calcium would be more appropriate to estimate free calcium in ESKD patients.', 'In 82 haemodialysis patients, serum ionized calcium (Ca(ion)) and pH were measured by blood gas analyser with ion-selective electrodes at the point-of-care, while bicarbonate, phosphate, albumin, magnesium and total calcium (Ca(tot)) were measured at the central laboratory. Linear regression analysis of measured variables was used to best fit adjusted calcium versus Ca(ion).', 'The most parsimonious multiple linear regression model (r(2) = 0.81) of variables associated with Ca(ion) included Ca(tot) (coeff 0.820, P < 0.0001), albumin (coeff -0.016, P < 0.0001) and phosphate (coeff -0.063, P < 0.002). Modelling of available variables yielded the following equation to adjust calcium for albumin and phosphate: Ca(albPh) = Ca(tot) + (0.015 x (40 - [albumin]) + 0.07 x (1.5 - [phosphate])). At an ambient albumin of 40 g/L, Ca(albPh) would be 0.07 mmol/L lower than Ca(tot) for every mmol/L of phosphate. In vitro data using three different albumin levels and increasing phosphate concentrations demonstrated this relationship, with the slope of the phosphate effect being stronger at lower albumin concentrations.
Answer: Because guidelines recommendations indicate that corrected serum calcium should be maintained within the normal range in ESKD patients, inclusion of phosphate to correct Ca(tot) in these patients may have clinical implications on the choice of phosphate binders and the prescription of vitamin D or calcimimetic agents.


Output: Is serum phosphate an important determinant of corrected serum calcium in end-stage kidney disease?