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.

Input: Consider Input: Context: To analyze the effect of antiretroviral therapy, including drugs that have good penetration in cerebrospinal fluid (CSF), on neuropsychologic performance.', 'One hundred sixty-five HIV-1-infected patients exposed to a stable highly active antiretroviral therapy (HAART) regimen were studied. Neuropsychologic examinations were performed for all patients.', "A total of 50.3% of patients were impaired. In multivariate analysis, older age (for 10-year increase, odds ratio [OR] = 4.8, 95% confidence interval [CI]: 2.2 to 10.4; P< 0.0001) and higher plasma HIV-1 RNA levels (OR = 1.90, 95% CI: 1.1 to 3.2; P = 0.021) at testing were independently associated with an increased probability of impaired neurocognitive performance, whereas higher educational level was a protective factor (OR = 0.76, 95% CI: 0.65 to 0.90; P=0.001). A significant linear correlation was observed between the neuropsychologic z score for 8 tests (NPZ8) score, a quantitative parameter of neurocognitive impairment, and CD4 cell count at neuropsychologic testing (R = 0.273, P = 0.001) and between the NPZ8 score and the patient's age (R = 0.288, P = 0.001).
Answer: Our study indicates that the use of stable HAART, including multiple drugs that have good CSF penetration, was not associated with neuropsychologic performance. To prevent independent replication of HIV in CSF with better control of a relevant reservoir of HIV is one of the crucial aims of therapeutic strategy.

Output: Do neuroactive antiretroviral drugs influence neurocognitive performance in less advanced HIV-infected patients responding to highly active antiretroviral therapy?


Input: Consider Input: Context: Diagnosis of partial anomalous pulmonary venous return is usually suspected by echocardiography and often confirmed by cardiac catheterization. Magnetic resonance imaging is a powerful non-invasive diagnostic tool that can give accurate insight on systemic and pulmonary veins, cardiac anatomy and physiopathology.', 'To test the diagnostic accuracy of magnetic resonance in patient with suspected partial anomalous pulmonary venous return.', 'Twenty consecutive patients (10 male, mean age: 27+/-20 years) with suspected partial anomalous pulmonary venous return underwent a magnetic resonance study comprehensive of Gadolinium-enhanced three-dimensional magnetic resonance angiography and phase-velocity-contrast in order to evaluate pulmonary and systemic venous anatomy and QP/QS. In 14 of them a cardiac catheterization was also performed. Anatomy findings and QP/QS result of both exams were compared. Sixteen patients underwent surgical correction. In the other four patients with QP/QS<1.5, surgical correction was not indicated according to the literature (1). Among patients who had both magnetic resonance and cardiac catheterization (14 patients) anatomical findings were concordant in 12 of them. In all operated patients, surgical findings were concordant with MRI report. There was a good correlation between magnetic resonance and cardiac catheterization QP/QS evaluation (mean value 2.23 and 2.4, respectively).
Answer: In patients with suspected anomalous pulmonary venous return, magnetic resonance provides a comprehensive evaluation of pulmonary venous return and the amount of shunt, overcoming most of the limitations of echocardiography. Therefore magnetic resonance is a powerful diagnostic tool for indicating therapeutic management and surgical strategies for this group of patients, and can be considered a non-invasive alternative to cardiac catheterization.

Output: Is magnetic resonance imaging the diagnostic tool of choice in the preoperative evaluation of patients with partial anomalous pulmonary venous return?


Input: Consider Input: Context: Strontium ranelate reduces fracture risk in postmenopausal women with osteoporosis. Evidence from non-clinical studies and analyses of bone markers in phase III trials indicate that this is due to an increase in osteoblast formation and a decrease of osteoclastic resorption. The aim of this work was to investigate, in human cells, the mechanisms by which strontium ranelate is able to influence the activities of osteoblasts and osteoclasts.', 'Human primary osteoblasts were used to examine effects of strontium ranelate on replication (thymidine incorporation), differentiation (Runx2 and alkaline phosphatase) and cell survival (cell counts and caspase activity). Osteoprotegerin (OPG) was measured by quantitative reverse transcription PCR (qRT-PCR) and elisa and receptor activator of NFkappaB ligand (RANKL) by qRT-PCR and Western blot. As strontium ranelate has been proposed as an agonist of the calcium-sensing receptor (CaSR), the involvement of CaSR in the effects of strontium ranelate on OPG and RANKL expression, and cell replication was examined using siRNA.', 'Strontium ranelate increased mRNA and protein levels of OPG and suppressed those of RANKL. Strontium ranelate also stimulated osteoblast replication and differentiation and increased cell survival under stress. Knocking down CaSR suppressed strontium ranelate-induced stimulation of OPG mRNA, reduction of RANKL mRNA, and increase in replication, indicating the involvement of CaSR in these responses.
Answer: Our results demonstrate that osteoblasts play a key role in the mechanism of action of the anti-fracture agent, strontium ranelate by mediating both its anabolic and anti-resorptive actions, at least in part, via activation of CaSR.


Output: Do osteoblasts play key roles in the mechanisms of action of strontium ranelate?