In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

[Q]: Context: Sufentanil is an intravenous opioid often used as a component of anesthesia during neurosurgical procedures. However, the effects of sufentanil on intracranial pressure in patients with diminished intracranial compliance are not well established, and remain controversial.', 'Ten patients with head trauma, in each of whom the trachea was intubated, were studied for the effects of sufentanil on intracranial pressure (ICP) and on cerebral perfusion pressure (CPP). In all patients, ICP monitoring was instituted before the study. Sedation was obtained using a propofol infusion, and paralysis was achieved with vecuronium. After obtaining control of ICP (between 15 and 25 mmHg) hemodynamic values and blood gas tensions (PaCO2 between 30 and 35 mmHg), the level of sedation was deepened with an intravenous injection of sufentanil (1 microgram/kg over 6 min), followed by an infusion of 0.005 microgram.kg-1min-1. Mean arterial pressure (MAP), ICP (fiberoptic intracranial pressure monitor), and end-tidal CO2 were continuously measured and recorded at 1-min intervals throughout the 30-min study period.', 'Sufentanil injection was associated with a statistically significant increase in ICP of 9 +/- 7 mmHg (+ 53%), which peaked at 5 min. Then ICP gradually decreased and returned to baseline after 15 min. This was accompanied by a significant decrease in MAP (24% decrease) and, thus, CPP (38% decrease). After 5 min, MAP and CPP gradually increased, but remained significantly decreased throughout the study.\Question: Does sufentanil increase intracranial pressure in patients with head trauma?
[A]: The results of the current study indicate that caution should be exercised in the administration of sufentanil bolus to patients with abnormal intracranial elastance, particularly if ICP is significantly increased.

[Q]: Context: The use of a system for continuous control of endotracheal tube cuff pressure reduced the incidence of ventilator-associated pneumonia (VAP) in one randomized controlled trial (RCT) with 112 patients but not in another RCT with 142 patients. In several guidelines on the prevention of VAP, the use of a system for continuous or intermittent control of endotracheal cuff pressure is not reviewed. The objective of this study was to compare the incidence of VAP in a large sample of patients (n=284) treated with either continuous or intermittent control of endotracheal tube cuff pressure.', 'We performed a prospective observational study of patients undergoing mechanical ventilation during more than 48 hours in an intensive care unit (ICU) using either continuous or intermittent endotracheal tube cuff pressure control. Multivariate logistic regression analysis (MLRA) and Cox proportional hazard regression analysis were used to predict VAP. The magnitude of the effect was expressed as odds ratio (OR) or hazard ratio (HR), respectively, and 95% confidence interval (CI).', 'We found a lower incidence of VAP with the continuous (n=150) than with the intermittent (n=134) pressure control system (22.0% versus 11.2%; p=0.02). MLRA showed that the continuous pressure control system (OR=0.45; 95% CI=0.22-0.89; p=0.02) and the use of an endotracheal tube incorporating a lumen for subglottic secretion drainage (SSD) (OR=0.39; 95% CI=0.19-0.84; p=0.02) were protective factors against VAP. Cox regression analysis showed that the continuous pressure control system (HR=0.45; 95% CI=0.24-0.84; p=0.01) and the use of an endotracheal tube incorporating a lumen for SSD (HR=0.29; 95% CI=0.15-0.56; p<0.001) were protective factors against VAP. However, the interaction between type of endotracheal cuff pressure control system (continuous or intermittent) and endotracheal tube (with or without SSD) was not statistically significant in MLRA (OR=0.41; 95% CI=0.07-2.37; p=0.32) or in Cox analysis (HR=0.35; 95% CI=0.06-1.84; p=0.21).\Question: Does continuous endotracheal tube cuff pressure control system protect against ventilator-associated pneumonia?
[A]: The use of a continuous endotracheal cuff pressure control system and/or an endotracheal tube with a lumen for SSD could help to prevent VAP in patients requiring more than 48 hours of mechanical ventilation.

[Q]: Context: Patients with glioblastoma multiforme (GBM) have an overall median survival of 15 months. This catastrophic survival rate is the consequence of systematic relapses that could arise from remaining glioblastoma stem cells (GSCs) left behind after surgery. We previously demonstrated that GSCs are able to escape the tumor mass and specifically colonize the adult subventricular zones (SVZs) after transplantation. This specific localization, away from the initial injection site, therefore represents a high-quality model of a clinical obstacle to therapy and relapses because GSCs notably retain the ability to form secondary tumors.', 'In this work, we questioned the role of the CXCL12/CXCR4 signaling in the GSC-specific invasion of the SVZs.', 'We demonstrated that both receptor and ligand are respectively expressed by different GBM cell populations and by the SVZ itself. In vitro migration bio-assays highlighted that human U87MG GSCs isolated from the SVZs (U87MG-SVZ) display stronger migratory abilities in response to recombinant CXCL12 and/or SVZ-conditioned medium (SVZ-CM) compared with cancer cells isolated from the tumor mass (U87MG-TM). Moreover, in vitro inhibition of the CXCR4 signaling significantly decreased the U87MG-SVZ cell migration in response to the SVZ-CM. Very interestingly, treating U87MG-xenografted mice with daily doses of AMD3100, a specific CXCR4 antagonist, prevented the specific invasion of the SVZ. Another in vivo experiment, using CXCR4-invalidated GBM cells, displayed similar results.\Question: Do adult mouse subventricular zones stimulate glioblastoma stem cells specific invasion through CXCL12/CXCR4 signaling?
[A]:
Taken together, these data demonstrate the significant role of the CXCL12/CXCR4 signaling in this original model of brain cancer invasion.