TASK DEFINITION: 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.
PROBLEM: Context: Previous studies have suggested that post-irradiation GH insufficiency results from a loss of GHRH secretion, since many patients were able to release GH following exogenous GHRH stimulation. However, supramaximal doses of GHRH were used and the response may decline with time after radiotherapy. We re-evaluated the GHRH dose-response curve in patients post cranial irradiation and in controls.', 'Randomized controlled study.', 'Five adult male long-term survivors of childhood brain tumours (median age 21.8 years (18.4-26.7); 13.7 years (11.4-15.7) post-radiotherapy, >30Gy) and five matched controls were studied. An intravenous bolus of GHRH(1-29)NH(2) was administered in doses at the lower (0.05 microg/kg) and upper (0.15 microg/kg) range of the dose-response curves for young males, as well as the standard supramaximal dose (1. 0 microg/kg). GH was measured before stimulation, every 2min for the first hour and every 5min for the second hour. All studies were conducted in a random fashion.', 'Significantly lower peak and area under the curve (AUC) GH concentrations occurred in the irradiated group using 0.15 microg/kg (median peak Irradiated, 4. 5mU/l vs median Controls, 37.4mU/l; P<0.01) and 1.0 microg/kg (median peak Irradiated, 4.8mU/l vs median Controls, 15.2mU/l; P<0. 05) GHRH(1-29)NH(2). In irradiated subjects there was an incremental rise in GH output with increasing doses of GHRH(1-29)NH(2 )(median AUC: 122mU/l.min vs 179mU/l.min vs 268mU/l.min; P=0.007) reflecting altered pituitary sensitivity and reduced responsiveness.
Answer: The GH response to bolus GHRH(1-29)NH(2) is attenuated in adult long-term survivors of childhood brain tumours. This may reflect direct pituitary damage and/or the loss of the tropic effects of chronic GHRH deficiency.

SOLUTION: Is the GH response to low-dose bolus growth hormone-releasing hormone ( GHRH ( 1-29 ) NH2 ) attenuated in patients with longstanding post-irradiation GH insufficiency?

PROBLEM: Context: Proprotein convertase subtilisin kexin-like 9 (PCSK9) is a secreted glycoprotein that is transcriptionally regulated by cholesterol status. It modulates levels of circulating low density lipoprotein cholesterol (LDLC) by negatively regulating low density lipoprotein receptor (LDLR) levels. PCSK9 variants that result in 'gain of function' have been linked to autosomal dominant hypercholesterolemia, while significant protection from coronary artery disease has been documented in individuals who carry 'loss of function' PCSK9 variants. PCSK9 circulates in human plasma, and we previously reported that plasma PCSK9 is positively correlated with total cholesterol and LDLC in men.", 'Herein, we report the effects of two lipid-modulating therapies, namely statins and fibrates, on PCSK9 plasma levels in human subjects. We also document their effects on endogenous PCSK9 and LDLR expression in a human hepatocyte cell line, HepG2, using immunoprecipitation and immunoblot analyses. Changes in plasma PCSK9 following fenofibrate or gemfibrozil treatments (fibric acid derivatives) were inversely correlated with changes in LDLC levels (r = -0.558, p = 0.013). Atorvastatin administration (HMGCoA reductase inhibitor) significantly increased plasma PCSK9 (7.40%, p = 0.033) and these changes were inversely correlated with changes in LDLC levels (r = -0.393, p = 0.012). Immunoblot analyses of endogenous PCSK9 and LDLR expression by HepG2 cells in response to statins and fibrates showed that LDLR is more upregulated than PCSK9 by simvastatin (2.6x vs 1.5x, respectively at 10 muM), while fenofibrate did not induce changes in either.
Answer: These results suggest that in vivo (1) statins directly increase PCSK9 expression while (2) fibrates affect PCSK9 expression indirectly through its modulation of cholesterol levels and (3) that these therapies could be improved by combination with a PCSK9 inhibitor, constituting a novel hypercholesterolemic therapy, since PCSK9 was significantly upregulated by both treatments.

SOLUTION: Are plasma PCSK9 levels significantly modified by statins and fibrates in humans?

PROBLEM: Context: Private umbilical cord blood (UCB) banking after delivery has increased over the last decade. For adult/somatic stem cell research UCB is an essential source of stem cells and researchers question if the number of UCB samples for research might be reduced by private banking.', 'A survey among seven private blood banks in Germany and analysis and comparison of the number of UCB samples donated for research within the STEMMAT project with private blood banking were performed from 03/2003 to 06/2005 at the Frauenklinik (OB/GYN), Technical University Munich, Germany.', 'Within 27.5 months 1,551 UCB samples were collected for research purposes; the effective recruitment rate was higher than expectations at an effective 66.2 %. Private UCB banking [n = 24] was distributed among three cord blood banks [n = 16, 6 and 4]. The rate of private blood banking was 0.99 % for all deliveries, thus reducing the effective rate for research purpose by only 1.5 %.
Answer: Under the assumption of active and successful recruitment of scientific UCB samples, private blood banking does not significantly reduce this rate and therefore is a negligible rival in the competition for sufficient numbers of UCB samples for research.

SOLUTION:
Does [ Private umbilical cord blood banking reduce the number of samples for scientific stem cell research ]?