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.
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Question: 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 -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 -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 -catenin in brain endothelial cells of hemorrhagic lesions of hemorrhagic stroke patients.
Answer: These results demonstrate the prerequisite role of endothelial -catenin in maintaining the integrity of adult BBB. The results suggest that BBB dysfunction secondary to defective -catenin transcription activity is a key pathogenic factor in hemorrhagic stroke, seizure activity, and central nervous system inflammation.

Answer: Does endothelial -Catenin Signaling be Required for Maintaining Adult Blood-Brain Barrier Integrity and Central Nervous System Homeostasis?

Question: Context: To determine the prevalence of five physical frailty phenotype components and to assess the relationship between them and other clinical factors.', "A population-based cross-sectional study was performed. Subjects 75 years and older were randomly selected from primary care databases (with sampling stratified by gender). Physical frailty phenotypes were assessed using Fried's criteria. Sociodemographic data, comorbidities, nutritional status, and functional capacity were assessed.", '126 subjects were recruited (47% women). Prevalence rates were poor muscle strength: 50%; low physical activity: 29%; slow gait: 28%; exhaustion: 27%; and weight loss: 5%. Prefrailty and frailty prevalence rates were 35.7% and 29.4%, respectively. Poor muscle strength and low physical activity showed a close relationship and concordance (kappa = 0.92). Most frailty components were associated with outdoor activity, hours walked daily, and certain comorbidities.
Answer: Poor muscle strength was the most prevalent frailty component and was closely associated with physical activity, suggesting that training programs may revert or prevent the frailty process.

Answer: Do poor Muscle Strength and Low Physical Activity Are the Most Prevalent Frailty Components in Community-Dwelling Older Adults?

Question: Context: Platelet-activating factor (PAF) is a potent stimulator of eosinophils. Recently, treatment with a protein kinase C (PKC) inhibitor which generally inhibits PKC isoforms has been shown to modulate several eosinophil functions in distinct manners, in that PKC inhibition enhanced CD11b expression and cellular adhesion, but inhibited superoxide generation and degranulation in PAF-stimulated human eosinophils. These results suggested that distinct PKC isoforms were likely to be involved in each eosinophil function induced by PAF. We have therefore investigated whether or not the PKC isoforms involved in PAF-induced CD11b expression and superoxide generation were different.', 'Human eosinophils prepared from healthy volunteers were treated with PKC inhibitors, bis-indolylmaleimide I (BisI; a general PKC inhibitor), myristoylated PKC inhibitor peptide (myr-psiPKC; a PKCalpha, beta and delta inhibitor) and rottlerin (a PKCdelta inhibitor), followed by stimulation with PAF. CD11b expression was determined using flow cytometry and superoxide generation was evaluated using a cytochrome c reduction assay.', 'BisI treatment led to enhancement of PAF-induced CD11b expression, while myr-psiPKC and rottlerin did not. In contrast, PAF-induced superoxide generation was inhibited by treatment with BisI, myr-psiPKC and rottlerin.
Answer: PKCalpha, beta and delta are not involved in PAF-induced CD11b expression, but PKCdelta is involved in the PAF-induced activation of superoxide anion generation.

Answer:
Are distinct isoforms of protein kinase C involved in human eosinophil functions induced by platelet-activating factor?