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.

Context: Old compared with young adults walk with reduced ankle and increased hip mechanical output. We examined the idea that age, leg strength, or both are related to the age-related changes in mechanical output during gait.', 'Healthy young (n = 32, age 21.5 years) and old adults (n = 32, age 76.8 years) participated in biomechanical gait analyses at 1.5 m/s and were also measured for maximal leg strength.', 'Analysis 1 confirmed previous data as old compared with young adults walked with 50 % more hip positive work and 18 % less ankle positive work. Analysis 2 showed that leg strength did not affect gait kinetics in groups of subjects with similar ages. In a weak young and a strong old group, Analysis 3 showed that old adults still walked with 23 % greater hip positive work. The group by joint interaction in Analysis 4 was suggestive of an even greater reliance on hip and less reliance on ankle work in weak compared with strong old adults.
Answer: Age and leg strength both contribute to the age-related changes in mechanical output during gait. Exercise prescription, normally targeting the knee extensors, should also involve ankle and hip muscles.
Do age and muscle strength mediate the age-related biomechanical plasticity of gait?

Context: Anti-Mullerian hormone (AMH) may have a role in disordered folliculogenesis in polycystic ovary syndrome (PCOS). Though there have been several investigations into circulating AMH levels in patients with PCOS, no previous studies have compared AMH concentrations in the follicular fluid of unstimulated ovaries in women with PCOS with that of normally ovulating women.', 'Follicular fluid was aspirated from 4-8-mm follicles of unstimulated ovaries during routine laparoscopy or laparotomy from women with anovulatory PCOS (n = 11) and those with regular ovulatory cycles (n = 8). Follicular AMH was compared in the two groups. Serum samples were analysed for AMH and endocrine profile.', 'Follicular fluid AMH levels were significantly higher (P < 0.0001) in women with anovulatory PCOS (median: 466.2 ng/ml) compared with normal-ovulatory controls (median: 78.0 ng/ml). Mean follicular fluid AMH levels in PCOS patients were 60 times higher than in the serum. Moreover, there was a significant correlation between the follicular fluid and serum concentrations of AMH in the PCOS group (r = 0.86; P = 0.007) but not in controls.
Answer: Highly elevated AMH in follicular fluid from PCOS patients in contrast to age-matched normal controls suggests that increased circulating concentrations of AMH are partly due to the increased production of AMH by individual follicles and not simply attributable to the increased number of small antral follicles. This suggests an intrinsic abnormality in the ovarian follicles themselves in PCOS, which could contribute to disordered folliculogenesis.
Is anti-Mullerian hormone increased in follicular fluid from unstimulated ovaries in women with polycystic ovary syndrome?

Context: To investigate the effect of targeted antiosteosarcoma methotrexate-bisphosphonate conjugate on growth inhibition and apoptosis in human osteosarcoma MG-63 cells.', 'MG-63 cells were treated with various concentrations of methotrexate-bisphosphonate conjugate and apoptosis was monitored via an MTT assay, cell morphology, TUNEL assay and flow cytometry analysis.', 'The survival rate of MG-63 cells treated for 24 to 96 hours with 2000 mg/ml or more of methotrexate-bisphosphonate conjugate decreased significantly. Cells treated with conjugate showed typical apoptotic features using inverted phase contrast microscopy and fluorescence staining, and the majority of cells demonstrated a positive result in the TUNEL assay. Karyopyknosis and crescent aggregation of chromatin were observed in conjugate-treated cells by electron microscopy. Flow cytometry of MG-63 cells treated with methotrexate-bisphosphonate conjugate showed a time and dose-dependent increase in apoptosis (p < 0.05).
Answer: A targeted antiosteosarcoma methotrexate-bisphosphonate conjugate induces apoptosis in human osteosarcoma MG-63 cells. This new conjugate is a valuable experimental tool for the therapy of osteosarcoma.

Does targeted antiosteosarcoma methotrexate-bisphosphonate conjugate induce apoptosis of osteosarcoma cells in vitro?