TASK DEFINITION: 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.
PROBLEM: Large concentrations of meperidine inhibit N-methyl-D-aspartate-(NMDA) receptor channels by channel block mechanisms. Extracellular pH regulates the activity and drug sensitivity of NMDA-receptor channels. We examined the influence of extracellular pH on sensitivity to meperidine of epsilon/zeta heteromeric NMDA-receptor channels expressed in Xenopus oocytes. Inhibition of epsilon1/zeta1, epsilon2/zeta1, epsilon3/zeta1, and epsilon4/zeta1 channels by meperidine was dependent on pH, with more inhibition at acidic pH and less inhibition at alkaline pH. The degree of voltage-dependence of meperidine block was only slightly affected by changes in pH, whereas affinity for meperidine was greatly reduced at alkaline pH. Furthermore, interaction of meperidine with Mg(2+) block was reduced at alkaline pH. Because the percentage of the protonated form of meperidine is only slightly affected by pH, changes in properties of the meperidine binding site may be involved in mechanisms of alteration of meperidine potency by pH.

SOLUTION: Is n-methyl-D-aspartate receptor channel block by meperidine dependent on extracellular pH?

PROBLEM: Glutathione S-transferases (GSTs) are involved in the metabolism of carcinogens and anticancer drugs. Functional polymorphisms exist in at least three genes that code for the GSTs, such as the GSTM1 and GSTT1 gene deletions or the A-G transition within the GSTP1 gene, which represents distinct GSTP1a and GSTP1b alleles. In the present case-control study, we aimed at estimation of the relationship between the GSTM1, GSTT1, and GSTP1 genotypes and the susceptibility to various types of childhood malignancies and the early relapses of diseases.', 'Using the polymerase chain reaction on the DNA extracted from peripheral blood leukocytes, we identified the GSTM1, GSTT1, and GSTP1 genotypes in 234 children at the initial stage of a childhood malignancy as well as in 460 age-and sex-matched healthy subjects who served as controls. The follow-up period for the effects of the anticancer therapy ranged from 11 to 43 months.', 'Compared to the controls, a significant increase in the frequency of the GSTP1b/GSTP1b genotype (odds ratio (OR) 5.7; 95% confidence limit (CL) from 2.4 to 13.8; Pearsons Chi-square P = 0.0001) was detected in the children with neoplasms. The GSTM1 and GSTT1 genotypes did not show any correlation with the risk of the de novo diagnosed neoplasms. During the observation, 62 children (26%) were found to be present with a local or disseminated recurrence of the diseases. The analysis indicated a trend in increasing risk of relapse for carriers of the GSTP1a allele (OR = 3.29; 95% CL from 0.73 to 14.67 P = 0.03).

SOLUTION: Is polymorphism within the glutathione S-transferase P1 gene associated with increased susceptibility to childhood malignant diseases?

PROBLEM: Anxiety and depression frequently co-occur in the elderly and in patients with dementia. Prior research has shown that depression is related to the risk of dementia, but the effect of anxiety on dementia remains unclear. We studied whether anxiety symptoms and anxiety disorders are associated with the risk of dementia and cognition.', 'We studied 2,708 nondemented participants from the prospective, population-based Rotterdam Study who underwent the Hospital Anxiety and Depression Scale (HADS) (sample I, baseline 1993-1995) and 3,069 nondemented participants who underwent screening for anxiety disorders (sample II, baseline 2002-2004). In 1993-1995, anxiety symptoms were assessed using the HADS. In 2002-2004, anxiety disorders were assessed using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. In both study samples, participants were continuously monitored for dementia until January 1, 2011. Cognition was tested in 2002-2004 and at a follow-up visit in 2009-2011 in sample II only.', 'In sample I, 358 persons developed dementia, and in sample II, 248 persons developed dementia. We did not find an association with the risk of dementia for anxiety symptoms (hazard ratio 1.05, 95% confidence interval: 0.77-1.43, Wald statistic 0.08, p= 0.77, df= 1) or for anxiety disorders (hazard ratio 0.92, 95% confidence interval: 0.58-1.45, Wald statistic 0.14, p= 0.71, df= 1). We could demonstrate an association of anxiety disorders with poor cognition cross-sectionally, but this attenuated after additional adjustments.

SOLUTION:
Is anxiety associated with the risk of dementia or cognitive decline : the Rotterdam Study?