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.

Input: Consider Input: Pathologic change in Alzheimer disease (AD) begins some years before symptoms. MRS has the potential to detect metabolic abnormalities reflecting this early pathologic change. Presenilin 1 (PS1) and amyloid precursor protein (APP) mutation carriers have a nearly 100% risk of developing AD and may be studied prior to symptom onset.', 'Short echo time proton MR spectra were acquired from a midline posterior cingulate voxel in presymptomatic carriers of PS1 or APP mutations ("presymptomatic mutation carriers" [PMCs]; n = 7) and age- and sex-matched control subjects (n = 6). Ratios of N-acetyl aspartate (NAA), myo-inositol (MI), and choline-containing compounds (Cho) to creatine (Cr) were measured and NAA/MI calculated. Regression analyses and t tests were performed after log transformation.', 'PMC and control subjects were matched for age and sex. PMC subjects were 1.7 to 21.6 years (mean 9.8 years) before expected symptom onset, predicted from family-specific mean age at onset. Age did not significantly affect metabolite ratios. Geometric mean ratios in control subjects were as follows: NAA/Cr = 1.75, MI/Cr = 0.59, and NAA/MI = 2.95. NAA/Cr and NAA/MI were significantly reduced in PMC relative to controls (NAA/Cr mean decrease 10% [95% CI 2 to 18%]; NAA/MI mean decrease 25% [95% CI 3 to 44%]). MI/Cr was increased in PMC, but the differences did not achieve significance (19% increase [95% CI 1% decrease to 41% increase]; p = 0.07)). In PMCs, reduction in NAA/MI (p = 0.001) and MI/Cr (p = 0.002) were related to proximity of expected age at onset.

Output: Does mRS show abnormalities before symptoms in familial Alzheimer disease?

Input: Consider Input: Allopregnanolone (3-hydroxy-5-pregnan-20-one) is a neurosteroid which has an inhibitory function through interaction with the GABAA receptor. This progesterone metabolite has strong sedative and anxiolytic properties, and low endogenous levels have been associated with depressed mood. This study aimed to investigate whether the very high serum allopregnanolone levels in late pregnancy covary with concurrent self-rated symptoms of depression and anxiety.', 'Ninety-six women in pregnancy weeks 37-40 rated symptoms of depression and anxiety with the Montgomery-Asberg Depression Rating Scale (MADRS-S) and Spielberger State-Trait Anxiety Inventory. Their serum allopregnanolone was analyzed by Celite chromatography and radioimmunoassay.', "Ten women had elevated depression scores (MADRS-S 13), and this group had significantly lower allopregnanolone levels compared to women with MADRS-S scores in the normal range (39.0 17.9 vs. 54.6 18.7 nmol/l, p = 0.014). A significant negative correlation was found between self-rated depression scores and allopregnanolone concentrations (Pearson's correlation coefficient = -0.220, p = 0.031). The linear association between self-rated depression scores and allopregnanolone serum concentrations remained significant when adjusted for gestational length, progesterone levels, and parity. Self-rated anxiety, however, was not associated with allopregnanolone serum concentrations during pregnancy.

Output: Is low serum allopregnanolone associated with symptoms of depression in late pregnancy?

Input: Consider Input: To assess whether cellular HIV-1 DNA prior to highly active antiretroviral therapy (HAART) initiation predicts its outcome.', 'Patients included all 51 hemophiliacs of the Greek component of the Multicenter Hemophilia Cohort Study who had initiated HAART and for whom cryopreserved lymphocyte samples before HAART initiation were available. Cellular HIV-1 DNA quantification was performed by a molecular beacon-based real-time PCR assay in multiple samples per patient with a median (interquartile range) follow-up of 76 (45-102) weeks.', 'The median (range) baseline HIV-1 DNA load was 297 (< 10 to 3468) copies per 1 x 10(6) peripheral blood mononuclear cells. Baseline HIV-1 DNA load did not predict initial virological response (VR). None of the patients with initial VR and baseline HIV-1 DNA load at or below the median experienced a subsequent virological rebound, while the cumulative probability of virological rebound by week 104 was 55% among those with HIV-1 DNA load greater than the median (P < 0.008). Cellular HIV-1 DNA load was the only parameter associated with sustained virological response as shown by univariate or multivariate analyses [adjusted odds ratio (95% confidence interval) 0.197 (0.048-0.801) per 1 log10 increase in DNA copies, P = 0.023].
Output: Does cellular HIV-1 DNA load predict HIV-RNA rebound and the outcome of highly active antiretroviral therapy?