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: Gastrin and pepsinogens reflect the functional state of the gastric mucosa.', 'To evaluate whether serum gastrin and pepsinogens correlate with the different grades of severity of gastro-oesophageal reflux disease (GERD).', "In all, 388 patients with heartburn not taking any form of acid suppressive therapy were matched-controlled for age and gender and sub-classified into four groups: group 1 non-erosive reflux disease (NERD); group 2, erosive reflux disease (ERD) Los Angeles (LA) A and B, group 3, ERD LA C and D; group 4 Barrett's oesophagus (BO). Fasting serum was analysed for gastrin 17, pepsinogen I, pepsinogen II und Helicobacter pylori using specific EIA tests (GastroPanel; Biohit, Plc).", 'Kruskal-Wallis test and analysis of variance.', 'There was a significant difference among the four groups with respect for pepsinogen I, but not for pepsinogen II, the pepsinogen I pepsinogen II ratio, H. pylori serology and gastrin levels. Pepsinogen I was the lowest in NERD and the highest in BO (median 91.6, mean +/- standard deviation 106.2 +/- 51.6 vs. median 114.7, mean +/- standard deviation 130.4 +/- 70.6; P = 0.046). Pepsinogen I levels were higher in H. pylori positive subjects. After adjusting for H. pylori status, the differences in pepsinogen I across patient groups were no longer statistically significant (P = 0.298).

Answer: Do serum gastrin and pepsinogens correlate with the different grades of severity of gastro-oesophageal reflux disease : a matched case-control study?


Question: 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.

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


Question: The antidepressant drug fluoxetine (FLU) is considered in the group of selective serotonine re-uptake inhibitors. Its distribution in brain and binding to human brain glutathione S-transferase-π (GST-π) have been shown. FLU can cross blood brain barrier and placenta, accumulate in fetus and may cause congenital malformations.', 'To elucidate the interaction of placental GST-π with FLU.', 'First, concentration-dependent inhibition of human placental GST-π was evaluated by using different FLU concentrations and then 0.3125, 0.625, 1.25, 2.5 and 5\u2009mM FLU concentrations were chosen and tested while keeping GSH concentration constant and 1-chloro-2,4-dinitrobenzene (CDNB) concentration varied and vice versa. The data were evaluated with different kinetic models and Statistica 9.00 for Windows.', 'The Vm, at variable [CDNB] (142\u2009±\u200916\u2009U/mg protein) was 3 times higher than the Vm obtained at variable [GSH] (49\u2009±\u20094\u2009U/mg protein). On the other hand, the Km for CDNB was ∼10 times higher than the Km for GSH (1.99\u2009±\u20090.36\u2009mM versus 0.21\u2009±\u20090.06\u2009mM). The IC50 value for FLU was 8.6\u2009mM. Both at constant [CDNB] and variable [GSH] and at constant [GSH] and variable [CDNB] the inhibition types were competitive with the Ki values of 5.62\u2009±\u20094.37 and 8.09\u2009±\u20091.27\u2009mM, respectively.

Answer:
Does fluoxetine-induced toxicity result in human placental glutathione S-transferase-π ( GST-π ) dysfunction?