TASK DEFINITION: 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.
PROBLEM: Context: Rapa Nui (Easter Island), located in the easternmost corner of the Polynesian Triangle, is one of the most isolated locations on the planet inhabited by humans. Archaeological and genetic evidence suggests that the island was first colonized by Polynesians around AD 1200, during their eastward expansion. Although it remains contentious whether Polynesians reached South America, suggestive evidence has been brought forward supporting the possibility of Native American contact prior to the European "discovery" of the island in AD 1722.', 'We generated genome-wide data for 27 Rapanui. We found a mostly Polynesian ancestry among Rapanui and detected genome-wide patterns consistent with Native American and European admixture. By considering the distribution of local ancestry tracts of eight unrelated Rapanui, we found statistical support for Native American admixture dating to AD 1280-1495 and European admixture dating to AD 1850-1895.
Answer: These genetic results can be explained by one or more pre-European trans-Pacific contacts.

SOLUTION: Do genome-wide ancestry patterns in Rapanui suggest pre-European admixture with Native Americans?

PROBLEM: Context: Downstream effects of muscarinic receptor stimulation in intestinal smooth muscle include contraction and intestinal transit. We thought to determine whether classic transient receptor potential (TRPC) channels integrate the intracellular signaling cascades evoked by the stimulated receptors and thereby contribute to the control of the membrane potential, Ca-influx, and cell responses.', 'We created trpc4-, trpc6-, and trpc4/trpc6-gene-deficient mice and analyzed them for intestinal smooth muscle function in vitro and in vivo.', 'In intestinal smooth muscle cells TRPC4 forms a 55 pS cation channel and underlies more than 80% of the muscarinic receptor-induced cation current (mI(CAT)). The residual mI(CAT) depends on the expression of TRPC6, indicating that TRPC6 and TRPC4 determine mI(CAT) channel activity independent of other channel subunits. In TRPC4-deficient ileal myocytes the carbachol-induced membrane depolarizations are diminished greatly and the atropine-sensitive contraction elicited by acetylcholine release from excitatory motor neurons is reduced greatly. Additional deletion of TRPC6 aggravates these effects. Intestinal transit is slowed down in mice lacking TRPC4 and TRPC6.
Answer: In intestinal smooth muscle cells TRPC4 and TRPC6 channels are gated by muscarinic receptors and are responsible for mI(CAT). They couple muscarinic receptors to depolarization of intestinal smooth muscle cells and voltage-activated Ca(2+)-influx and contraction, and thereby accelerate small intestinal motility in vivo.

SOLUTION: Does deletion of TRPC4 and TRPC6 in mice impair smooth muscle contraction and intestinal motility in vivo?

PROBLEM: Context: Atrial natriuretic peptide is a cardiac atrium-derived hormone and its cardioprotective effects have recently been confirmed, but the actual mechanism underlying these effects has not been well elucidated. In this study, we proposed that atrial natriuretic peptide achieves its effects in part via peroxisome proliferator activated receptor γ, a nuclear receptor.', 'Hemodynamic data in swine heart ischemia-reperfusion model were measured under the conditions of no medication for control (Group N, n\xa0=\xa08) or that of carperitide (synthetic human atrial natriuretic peptide) systemic administration (Group A, n\xa0=\xa08). After 30\xa0min of left anterior descending artery total occlusion and 4\xa0h of reperfusion, peroxisome proliferator activated receptor γ mRNA and protein expressions in cardiac muscle were examined. The mRNA expression of Liver X receptor α, the downstream agent of peroxisome proliferator activated receptor γ, was also evaluated. Creatine kinase-myocardial band and Troponin T elevations after reperfusion were evaluated as markers of cardiac damage.', 'The dP/dT decrease during reperfusion was ameliorated in Group A. Peroxisome proliferator activated receptor γ mRNA expression in Group A was significantly higher in ischemic area than that in Group N, although the difference was not significant in the marginal and non-ischemic areas. The peroxisome proliferator activated receptor γ protein expression in ischemic area was also significantly dominant in Group A.
Answer: Atrial natriuretic peptide may achieve its cardioprotective effects in part via the activation of the peroxisome proliferator activated receptor γ pathway, particularly in central areas of ischemic lesions.

SOLUTION:
Does atrial natriuretic peptide induce peroxisome proliferator activated receptor γ during cardiac ischemia-reperfusion in swine heart?