Given a passage with a context and an answer, 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.

[EX Q]: Context: To evaluate whether P2X3 receptors (P2X3R) are expressed in the bladder urothelium and to determine their possible function in modulating purinergic detrusor contractions in the rat urinary bladder.', 'The expression of urothelial receptors was determined using conventional immunohistochemistry in bladders from normal Sprague-Dawley rats. The urothelial layer was removed by incubation with protamine, and disruption of the urothelium was confirmed using haematoxylin and eosin staining on bladder sections. Open cystometry was used to determine the effects of both urothelial removal as well as intravesical application of a specific P2X3R antagonist on bladder properties from intact and protamine-treated rats. Isometric contractile responses to potassium chloride (KCl) depolarization, electrical field stimulation (EFS) or chemical P2X activation were determined in normal and urothelium-denuded bladder strips, with and without application of the P2X3R antagonist.', 'Immunohistochemical staining showed high expression of P2X3R in the medial and basal layers of the urothelium. Removal of the urothelial layer disturbed normal bladder performance in vivo and eliminated the effects of the P2X3R antagonist on increasing the contractile interval and reducing the amplitude of voiding contractions. Removal of the urothelium did not affect bladder strip contractile responses to KCl depolarization or EFS. Pharmacological inhibition of P2X3R prevented desensitization to P2X-mediated detrusor muscle contractions during EFS only in the strips with an intact urothelium. A concentration-dependent, specific inhibition of P2X3R also prevented desensitization of purinergic contractile responses in intact bladder strips.
Answer: In the rat bladder, medial and basal urothelial cells express P2X3R, and specific inhibition of the receptor leads to a more hyporeflexive bladder condition. This pathway may involve P2X3R driving a paracrine amplification of ATP released from umbrella cells to increase afferent transmission in the sub-urothelial sensory plexus and desensitization of P2X1-mediated purinergic detrusor contractions.
[EX A]: Does inhibition of urothelial P2X3 receptors prevent desensitization of purinergic detrusor contractions in the rat bladder?

[EX Q]: Context: Bone marrow stromal cell antigen 2 (BST2), also known as tetherin, HM1.24 or CD317 represents a type 2 integral membrane protein, which has been described to restrict the production of some enveloped viruses by inhibiting the virus release from the cell surface. This innate antiviral mechanism is counteracted by the HIV-1 viral factor Vpu, targeting BST2 for cellular degradation. Since antiviral BST2 activity has been mainly confirmed by in vitro data, we investigated its role in vivo on the disease progression using the SIV/macaque model for AIDS. We determined BST2 expression in PBMC and leukocyte subsets of uninfected and SIV-infected rhesus macaques by real-time PCR and flow cytometry and correlated it with disease progression and viral load.', 'Compared to pre-infection levels, we found increased BST2 expression in PBMC, purified CD4(+) lymphocytes and CD14(+) monocytes of SIV-infected animals, which correlated with viral load. Highest BST2 levels were found in progressors and lowest levels comparable to uninfected macaques were observed in long-term non-progressors (LTNPs). During acute viremia, BST2 mRNA increased in parallel with MX1, a prototype interferon-stimulated gene. This association was maintained during the whole disease course.
Answer: The detected relationship between BST2 expression and viral load as well as with MX1 indicate a common regulation by the interferon response and suggest rather limited influence of BST2 in vivo on the disease outcome.
[EX A]: Is increased BST2 expression during simian immunodeficiency virus infection a determinant of disease progression in rhesus monkeys?

[EX Q]: Context: Poor decision-making is a hallmark of addiction, whether to substances or activities. Performance on a widely used test of decision-making, the Iowa Gambling Task (IGT), can discriminate controls from persons with ventral medial frontal lesions, substance-dependence, and pathological gambling. Positron emission tomography (PET) studies indicate that substance-dependent individuals show altered prefrontal activity on the task. Here we adapted the IGT to an fMRI setting to test the hypothesis that defects in ventral medial and prefrontal processing are associated with impaired decisions that involve risk but may differ depending on whether substance dependence is comorbid with gambling problems.', '18 controls, 14 substance-dependent individuals (SD), and 16 SD with gambling problems (SDPG) underwent fMRI while performing a modified version of the IGT.', 'Group differences were observed in ventral medial frontal, right frontopolar, and superior frontal cortex during decision-making. Controls showed the greatest activity, followed by SDPG, followed by SD.
Answer: Our results support a hypothesis that defects in ventral medial frontal processing lead to impaired decisions that involve risk. Reductions in right prefrontal activity during decision-making appear to be modulated by the presence of gambling problems and may reflect impaired working memory, stimulus reward valuation, or cue reactivity in substance-dependent individuals.
[EX A]:
Is prefrontal cortex activity reduced in gambling and nongambling substance users during decision-making?