Given a passage, 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.

Example Input: Erectile dysfunction (ED) and atherosclerotic cardiovascular disease (ASCVD) share many common risk factors, and vascular ED is a marker for increased ASCVD risk. Low 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with increased ASCVD risk, but less is known regarding the relationship of low 25(OH)D with ED. We determined whether 25(OH)D deficiency is associated with ED independent of ASCVD risk factors.', 'We performed cross-sectional analyses of 3390 men aged 20 years free of ASCVD who participated in NHANES 2001-2004. Serum 25(OH)D was measured by the DiaSorin radioimmunoassay; deficiency was defined as levels <20ng/ml (<50nmol/L). Self-reported ED, assessed by a single validated question, was defined as men who reported being "never" or "sometimes able" to maintain an erection. We assessed the relationship between 25(OH)D deficiency and ED prevalence using adjusted Poisson regression methods.', 'After accounting for NHANES sampling, the weighted prevalence of 25(OH)D deficiency and of ED were 30% and 15.2%, respectively. 25(OH)D levels were lower in men with vs. those without ED (mean 22.8 vs 24.3ng/mL, respectively; p=0.0005). After adjusting for lifestyle variables, comorbidities, and medication use, men with 25(OH)D deficiency had a higher prevalence of ED compared to those with levels 30ng/ml (Prevalence Ratio 1.30, 95% CI 1.08-1.57).
Example Output: Is vitamin D deficiency independently associated with greater prevalence of erectile dysfunction : The National Health and Nutrition Examination Survey ( NHANES ) 2001-2004?

Example Input: The tumor necrosis factor (TNF) gene is located within the highly polymorphic major histocompatibility complex region, exhibiting the -308 GA promoter region polymorphism and six microsatellites (TNFa-f) spanning the region nearby the TNF locus.', 'In the present study, we evaluated the frequency of -308 GA and TNFa-e polymorphisms and respective haplotypes (in chromosomal sequence: TNFd-TNFe-308GA-TNFc-TNFa-TNFb), in 222 patients with AIDS, 52 of whom exhibited cytomegalovirus retinitis, and in 202 healthy HIV-negative individuals.', 'TNF microsatellite and single nucleotide polymorphism typings were performed by PCR followed by polyacrylamide gel electrophoresis.', 'The TNF-308A allele and the 4-3-G-2-7-1 haplotype were associated with susceptibility to AIDS, whereas the TNFb4 allele and the 3-3-G-1-11-4 haplotype were associated with protection against AIDS development. The TNFc2 allele and the 4-1-G-2-2-1 haplotype, which contains the TNFc2 allele, were associated with cytomegalovirus retinitis.
Example Output: Are tumor necrosis factor region polymorphisms associated with AIDS and with cytomegalovirus retinitis?

Example Input: In chronic pain, increased activity from intact or damaged peripheral nerve endings results in an enhanced response in central pain transmission systems, a mechanism known as central sensitization. Central sensitization can also be invoked in human experimental models. Therefore, these models may be useful to characterize novel analgesics in humans. The anticonvulsant gabapentin has demonstrated efficacy in patients with neuropathic pain, but its mode of action remains unclear. This study examined the effects of gabapentin on signs of central sensitization (brush and pinprick hyperalgesia) in a human model of capsaicin-evoked pain, using a gabapentin dosing regimen similar to that used in the clinic. The aims were to determine whether gabapentin, dosed in a manner similar to that used in the clinic, affected the various components of central sensitization and to assess the utility of this model for characterizing novel analgesics.', 'Intradermal capsaicin (100 microg/20 microl) was administered in the volar forearm of 41 male human volunteers to induce pain and clinical signs of central sensitization. Gabapentin (titrated to 2,400 mg daily) or placebo was given orally for 15 days in a randomized, double-blind, parallel-group design. The capsaicin test was conducted at baseline and after gabapentin or placebo. Endpoints were the size of areas of brush-evoked allodynia (with cotton gauze) and pinprick hyperalgesia (with von Frey filament), and the intensity of ongoing brush- and pinprick-evoked pain.', 'Gabapentin significantly reduced the area of brush allodynia compared with placebo (P </= 0.05) and insignificantly attenuated the area of pinprick hyperalgesia. Gabapentin had no significant effect on spontaneous and evoked pain intensity.
Example Output:
Does chronic oral gabapentin reduce elements of central sensitization in human experimental hyperalgesia?