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.

[Q]: Context: The blood-brain barrier (BBB) formed by brain endothelial cells interconnected by tight junctions is essential for the homeostasis of the central nervous system. Although studies have shown the importance of various signaling molecules in BBB formation during development, little is known about the molecular basis regulating the integrity of the adult BBB.', 'Using a mouse model with tamoxifen-inducible endothelial cell-restricted disruption of ctnnb1 (iCKO), we show here that endothelial β-catenin signaling is essential for maintaining BBB integrity and central nervous system homeostasis in adult mice. The iCKO mice developed severe seizures accompanied by neuronal injury, multiple brain petechial hemorrhages, and central nervous system inflammation, and all had postictal death. Disruption of endothelial β-catenin induced BBB breakdown and downregulation of the specific tight junction proteins claudin-1 and -3 in adult brain endothelial cells. The clinical relevance of the data is indicated by the observation of decreased expression of claudin-1 and nuclear β-catenin in brain endothelial cells of hemorrhagic lesions of hemorrhagic stroke patients.
Answer: These results demonstrate the prerequisite role of endothelial β-catenin in maintaining the integrity of adult BBB. The results suggest that BBB dysfunction secondary to defective β-catenin transcription activity is a key pathogenic factor in hemorrhagic stroke, seizure activity, and central nervous system inflammation.
[A]: Does endothelial β-Catenin Signaling be Required for Maintaining Adult Blood-Brain Barrier Integrity and Central Nervous System Homeostasis?


[Q]: Context: To establish a single-tube single-run multiplex PCR technique that can detect single or mixed samples with four species of Plasmodium.', 'Folding primers were designed based on the fast nested PCR. The reaction component concentrations were optimized and the primers were selected based on the annealing temperature. The established single-tube single-run folding-primer multiplex PCR (FP-PCR) was tested for its sensitivity and specificity to detect single-species and mixed samples with P. vivax, P. falciparum, P. ovale (including P. ovale wallikeri) and/or P. malariae.', 'In all the seven experimental repeats, FP-PCR successfully detected single-species infection for all the four species, with the detection limit reaching or close to 1 parasite/µl blood. For mixed infections with 2-4 species at different densities with the highest being 100 times of the lowest, FP-PCR identified all the species in each combination in 57 out of 84 tests. Further, in 10 dried blood samples on filter paper from healthy subjects, no FP-PCR amplification was found, except weak formation of dimers.
Answer: FP-PCR is a simple and sensitive method for detecting both single-species and mixed infections with human Plasmodium, and can be applied for malaria diagnosis, screening and monitoring.
[A]: Does [ Single-tube Single-run Multiplex PCR detect Mixed Samples with Four Species of Plasmodium ]?


[Q]: Context: Our aim was to analyze the effects of 3-month antihypertensive therapy by nebivolol, a beta-blocking agent with nitric oxide-mediated vasodilatory properties, on coronary flow reserve (CFR) and left ventricular filling pressure (LVFP) in uncomplicated arterial hypertension.', 'Twenty newly diagnosed, never treated, uncomplicated hypertensive patients (14 male and six female patients, mean age = 49 years), I-II WHO grade, underwent single-blind nebivolol treatment. At baseline and at 3-month follow-up, patients underwent Doppler echocardiography including pulsed Tissue Doppler of septal mitral annulus: the ratio between transmitral E velocity and myocardial early diastolic velocity (E/Em ratio) was calculated as an index of LVFP degree. Transthoracic Doppler-derived CFR (high-dose dipyridamole coronary diastolic peak flow velocity to resting coronary peak flow velocity ratio) of distal left anterior descending artery was also determined.', 'After 3-month nebivolol therapy, rate-pressure product decreased (P < 0.0001). No significant change of left ventricular mass index, relative wall thickness and midwall shortening was detected. Left ventricular end-diastolic diameter and stroke volume were both marginally increased. Nebivolol increased Em (P < 0.0001), reduced E/Em ratio (from 9.0 +/- 1.6 to 8.2 +/- 1.1, P < 0.0001) and enhanced CFR (from 2.07 +/- 0.2 to 2.20 +/- 0.2, P = 0.003), because of increased hyperemic coronary flow velocity (P < 0.001). CFR increase remained significant (P < 0.001) after normalizing resting and dipyridamole coronary velocities for the respective rate-pressure product. The increase of normalized CFR induced by nebivolol was related with E/Em ratio decrease (r = -0.65, P < 0.002).
Answer: Nebivolol improves LVFP as well as CFR in uncomplicated hypertension. The association between changes of CFR and those of LVFP indicates a possible common denominator between improvement of coronary microvascular function and myocardial stimulation of nitric oxide release induced by the drug.
[A]:
Does nebivolol induce parallel improvement of left ventricular filling pressure and coronary flow reserve in uncomplicated arterial hypertension?