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.
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Question: Toenail onychomycosis is a common disease that can have serious adverse effects on the quality of life (QOL) of patients.', 'To evaluate the impact of itraconazole pulse therapy on the QOL of patients with toenail onychomycosis.', 'A total of 20 patients with disto-lateral subungual toenail onychomycosis were treated with itraconazole 200 mg twice daily for 1 week every 4 weeks for 12 weeks. The patients were asked to complete a QOL questionnaire before treatment and on the last follow-up visit (week 48). A score of 0-4 was given according to the five possible responses to each question and these were summed to give the final score of the patient. The mean of the final scores of the patients before and after treatment were compared using the Wilcoxon matched-pairs test.', 'At 48 weeks after commencing treatment, 14 patients (70%) responded to treatment (nine patients were cured with almost totally clear toenails and five patients improved), and 16 patients (80%) were mycologically cured (negative KOH smear and culture). The mean of the QOL scores of the patients before treatment was 18.0+/-7.8, which reduced to 13.1+/-11.3 after treatment (two-tailed, p=0.009).

Answer: Does itraconazole pulse therapy improve the quality of life of patients with toenail onychomycosis?


Question: Cocaine and alcohol are frequently used simultaneously and this combination is associated with enhanced toxicity. We recently showed that active cocaine abusers have a markedly enhanced sensitivity to benzodiazepines. Because both benzodiazepines and alcohol facilitate GABAergic neurotransmission we questioned whether cocaine abusers would also have an enhanced sensitivity to alcohol that could contribute to the toxicity. In this study we compared the effects of alcohol (0.75 g/kg) on regional brain glucose metabolism between cocaine abusers (n = 9) and controls (n = 10) using PET and FDG. Alcohol significantly decreased whole brain metabolism and this effect was greater in controls (26+/-6%) than in abusers (17+/-10%) even though they had equivalent levels of alcohol in plasma. Analysis of the regional measures showed that cocaine abusers had a blunted response to alcohol in limbic regions, cingulate gyrus, medial frontal and orbitofrontal cortices.

Answer: Do cocaine abusers show a blunted response to alcohol intoxication in limbic brain regions?


Question: Mutation of the Chx10 homeobox gene in mice and humans causes congenital blindness and microphthalmia (small eyes). This study used Chx10-/- (ocular retardation) mice to investigate how lack of Chx10 affects progenitor/stem cell behavior in the retina and ciliary epithelium (CE).', 'The distribution of mitotic retinal progenitor cells (RPCs) during embryonic development was analyzed using phosphohistone 3 (H3)-labeling. DNA flow cytometry was used to measure DNA content. The distribution and phenotype of dividing cells in the postnatal retina and CE was analyzed by incorporation of the thymidine analogue BrdU and immunohistochemistry.', 'The Chx10-/- embryonic retina maintained a constantly sized population of mitotic RPCs during development, causing the mitotic index to increase markedly over time compared with the wild type. Also, the proportion of cells in the G1 phase of the cell cycle was increased compared with the wild type. Of interest, division of RPC-like cells with neurogenic properties persisted in the adult Chx10-/- retina. Colabeling for BrdU and the neural progenitor marker nestin or the neuronal markers beta3-tubulin, syntaxin, and VC1.1 showed that new amacrine-like neurons developed in the adult central retina. By contrast, cells with these characteristics were not observed in the mature wild-type retina. In the mature CE, BrdU-positive cells were observed in both wild-type and Chx10-/- mice. However, neurogenesis from this cell population was not evident.

Answer:
Does absence of chx10 cause neural progenitors to persist in the adult retina?