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: Is the activity of sirtuin 3 (SIRT3) altered in granulosa and cumulus cells from young women with reduced ovarian reserve or women of advanced maternal age?
Answer: SIRT3 mRNA and active protein in granulosa and cumulus cells were decreased in women with reduced ovarian reserve and advanced maternal age.
[A]: Are mitochondrial SIRT3 and its target glutamate dehydrogenase altered in follicular cells of women with reduced ovarian reserve or advanced maternal age?


[Q]: Context: Patients with chronic heart failure (CHF) have multiple abnormalities of autonomic regulation that have been associated to their high mortality rate. Heart rate recovery immediately after exercise is an index of parasympathetic activity, but its prognostic role in CHF patients has not been determined yet.', 'Ninety-two stable CHF patients (83M/9F, mean age: 51+/-12 years) performed an incremental symptom-limited cardiopulmonary exercise testing. Measurements included peak O2 uptake (VO2p), ventilatory response to exercise (VE/VCO2 slope), the first-degree slope of VO2 for the 1st minute of recovery (VO2/t-slope), heart rate recovery [(HRR1, bpm): HR difference from peak to 1 min after exercise] and chronotropic response to exercise [%chronotropic reserve (CR, %)=(peak HR-resting HR/220-age-resting HR)x100]. Left ventricular ejection fraction (LVEF, %) was also measured by radionuclide ventriculography.', 'Fatal events occurred in 24 patients (26%) during 21+/-6 months of follow-up. HRR1 was lower in non-survivors (11.4+/-6.4 vs. 20.4+/-8.1; p<0.001). All cause-mortality rate was 65% in patients with HRR1<or=12 bpm versus 11% in patients with HRR1>12 bpm (log-rank: 32.6; p<0.001). By multivariate survival analysis, HRR1 resulted as an independent predictor of mortality (chi2=19.2; odds ratio: 0.87; p<0.001) after adjustment for LVEF, VO2p, VE/VCO2 slope, CR and VO2/t-slope. In a subgroup of patients with intermediate exercise capacity (VO2p: 10-18, ml/kg/min), HRR1 was a strong predictor of mortality (chi2: 14.3; odds ratio: 0.8; p<0.001).
Answer: Early heart rate recovery is an independent prognostic risk indicator in CHF patients and could be used in CHF risk stratification.
[A]: Does early heart rate recovery after exercise predict mortality in patients with chronic heart failure?


[Q]: Context: To investigate the specific role of Frizzled-related protein (FRZB) and Secreted frizzled-related protein 1 (SFRP1) in the onset and progression of Osteoarthritis (OA) using Frzb(-/-) and Sfrp1(-/-) mice in the destabilization of medial meniscus model (DMM), a slowly progressing model of OA. Secreted frizzled-related proteins (SFRPs) were identified as secreted Wingless-type (Wnt) antagonists. The Wnt signaling cascade is a major regulator in cartilage development, homeostasis and degeneration.', 'The DMM model was surgically induced in eight-week-old male C57/Bl6 Frzb(-/-), Sfrp1(-/-) or wild-type mice by transection of the medial meniscotibial ligament. Cartilage damage in the femoral and tibial articular surfaces was calculated following the Osteoarthritis Research Society International (OARSI) histopathology initiative guidelines. Histomorphometry was used to evaluate the subchondral bone plate thickness.', 'OA severity scores were significantly higher in the tibia of Frzb(-/-) mice as compared to littermates, whereas no interaction was seen between genotype and intervention in Sfrp1(-/-) mice. Moreover, the DMM model resulted in significantly greater subchondral bone changes compared to sham but was not different between Frzb(-/-) mice and littermates. In contrast, the subchondral bone properties in Sfrp1(-/-) mice were significantly different from littermates.
Answer: Using the DMM model, we demonstrated that FRZB and SFRP1 differentially modulate joint homeostasis in two distinct compartments of the joint. These data highlight the fine-tuning of Wnt signaling in joint homeostasis and disease, show differential regulation of the cascade in cartilage and subchondral bone, and provide further evidence for a role of endogenous Wnt modulators as key players in OA.
[A]:
Does loss of Frzb and Sfrp1 differentially affect joint homeostasis in instability-induced osteoarthritis?