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.

Context: Ischemic mitral regurgitation (MR) often persists after restrictive mitral valve annuloplasty, in which case it is associated with worse clinical outcomes. The goal of the present study was to determine whether persistence of MR and/or clinical outcome could be predicted from preoperative analysis of mitral valve configuration.', 'In 51 consecutive patients undergoing restrictive annuloplasty for ischemic MR, posterior leaflet (PL) angle, anterior leaflet angle, coaptation distance, and tenting area were quantified by echocardiography before surgery (6+/-3 days), and MR severity was assessed before and early after surgery (9+/-4 days). Postoperatively, persistence of mild to moderate MR (vena contracta > 3 mm) was observed in 11 (22%) of the patients. The best predictor of postoperative persistence of MR was a PL angle > or = 45 degrees (sensitivity 100%, specificity 97%, positive predictive value 92%, negative predictive value 100%). Patients with persistent MR had markedly lower 3-year event-free survival (26+/-20%) compared with those with nonpersistent MR (75+/-12%, P=0.01). Preoperative presence of a PL angle > or = 45 degrees also was associated with a markedly lower 3-year event-free survival (22+/-17% versus 76+/-12%; P<0.001).
Answer: In patients undergoing restrictive annuloplasty for ischemic MR, persistence of MR and 3-year event-free survival can accurately be predicted by preoperative analysis of mitral valve configuration. Patients with a PL angle > or = 45 degrees (ie, with high PL restriction) should thus be considered poor candidates for this procedure, and concomitant or alternative procedures should be contemplated.
Does preoperative posterior leaflet angle accurately predict outcome after restrictive mitral valve annuloplasty for ischemic mitral regurgitation?

Context: Before desflurane is advocated for patients undergoing neurosurgical procedures, it is necessary to determine the effect of desflurane on cerebral blood flow (CBF). In this study, CBF values are compared between desflurane and isoflurane at two doses. In addition, CBF reactivity to CO2 and the effect of prolonged exposure were compared between the two agents.', 'Cerebral blood flow measurements with intravenous 133Xe were performed in 24 patients undergoing craniotomy for mass lesions, randomized to receive either isoflurane or desflurane in oxygen and air. Cerebral blood flow was determined at 1 and 1.5 MAC concentrations at PaCO2 of 25 mmHg in the absence of surgical stimulation. Intraoperatively, with 1.25 MAC anesthesia, CBF was determined at target PaCO2 of 25 and 35 mmHg. In 15 patients, an additional measurement at 1.25 MAC was made before closure.', 'At 1.0 MAC, mean +/- SD CBF values for the desflurane and isoflurane groups were 18 +/- 2 and 20 +/- 3 ml x 100 g-1 x min-1, respectively. At 1.5 MAC, CBF values were the same for the two anesthetics; 17 +/- 3 ml x 100 g-1 x min-1 for isoflurane and 19 +/- 4 ml.100 g-1 x min-1 for desflurane. During 1.25 MAC anesthesia, there were no differences between groups, with CO2 reactivity 1.3 +/- 1.2 ml x 100 g-1 x min-1 x mmHg-1 for desflurane and 1.6 +/- 0.6 ml.100 g-1 x min-1 x mmHg-1 for isoflurane. There was no demonstrable decrease in CBF with prolonged exposure to either agent.
Answer: Desflurane and isoflurane are similar in terms of absolute CBF, the response to increasing doses, and the preservation of CO2 reactivity.
Do desflurane and isoflurane have similar effects on cerebral blood flow in patients with intracranial mass lesions?

Context: Acute rejection (AR) after organ transplantation results in transplant arteriosclerosis (TA). Endothelial progenitor cells (EPCs) are involved in tissue repair and blood vessel formation but are suspected to be a cause of TA.', 'In this study, we introduced a syngeneic and allogeneic abdominal aortic transplant model with C57BL/6 and BALB/c mice. Syngeneic and allogeneic grafts were histopathologically analyzed after transplantation. Bone marrow-derived EPCs were injected into transplant model animals to observe their distribution and temporal concentration changes. Changes of vascular endothelial growth factor receptor 1 (VEGFR-1), phosphorylated VEGFR-1 (pVEGFR-1), VEGFR-2, pVEGFR-2, protein kinase B (Akt), pAkt, extracellular signal-regulated kinase 1 (Erk1), pErk1 levels in EPCs upon VEGF165 and the VEGFR inhibitor Vandetanib exposure were analyzed in\xa0vitro with western blotting.', 'In the allogeneic transplant group, two weeks after transplantation, formations of new intima layers could be observed, and its proliferation gradually increased to four and six weeks post-transplantation (p\xa0<\xa00.05), accompanied by significant arterial stenoses. Exogenous EPCs mainly localized to the damaged sites of the transplant arteries. In\xa0vivo, Vandetanib caused a significant dose dependent decrease of transplant hyperplasia (p\xa0<\xa00.05) and inhibited VEGF related proliferation, migration and adhesion of EPCs.
Answer: Vandetanib treatment can reduce arteriosclerosis induced by abdominal aorta transplantation by blocking VEGFRs in EPCs.

Do endothelial progenitor cells induce transplant arteriosclerosis via VEGFR-1/2 activity?