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: Adipose tissue is responsible for releasing various adipokines that have been related to insulin resistance. Understanding the relationship of these adipokines to insulin resistance may foster the development of new treatments for diabetes.', 'The primary objective of this study was to determine whether an association between retinol-binding protein 4 (RBP4) and insulin resistance exists in nonobese individuals without a family history or diagnosis of diabetes. The secondary objective was to determine by a dual energy x-ray absorptiometry scan which adipose tissue depot most closely relates to RBP4 levels.', 'Cross-sectional analysis of 92 study participants ranging in age from 20 to 83 yr was performed. The range of body mass index (BMI) was from 18 to 30 kg/m(2). Exclusion criteria were a BMI greater than 30 kg/m(2), family history of diabetes, or a diagnosis of diabetes. Insulin sensitivity was determined by a hyperinsulinemic euglycemic clamp. Body fat was measured by dual energy x-ray absorptiometry scan.', 'RBP4 values were lower in females (35.8 +/- 1.7 microg/ml) compared with males (39.9 +/- 1.4 microg/ml; P = 0.06). RBP4 levels were found to correlate negatively with insulin sensitivity (r = -0.32; P = 0.002) and positively with age (r = 0.38; P < 0.001). RBP4 levels did not correlate with BMI (r = -0.13; P = 0.22), trunk fat (r = 0.16; P = 0.22), or percent body fat (r = 0.07; P = 0.65). However, RBP4 levels did correlate with percent trunk fat (r = 0.36; P = 0.001).
Answer: These findings indicate a relationship between RBP4, insulin sensitivity, and percent trunk fat in individuals who may not have features of insulin resistance.

SOLUTION: Is retinol-binding protein 4 associated with insulin resistance and body fat distribution in nonobese subjects without type 2 diabetes?

PROBLEM: Context: Cell death induced by intracellular glutathione depletion has been reported to be dependent on the presence of trace amounts of extracellular copper ions. Since little is known about the relationship between glutathione depletion and copper homeostasis, we have in the present study further investigated the role of low amounts of copper ions in glutathione depletion.', 'Glutathione turnover was investigated in HeLa and hepatoma cell cultures with normal and low cysteine content in the presence of copper ions (1 and 10micromol/L) and two other glutathione-stimulating agents (lipoic acid and mercury ions).', 'Copper ions (10micromol/L) caused relatively small increases in total amount of glutathione (the sum of the intracellular and the extracellular amount of glutathione) in HeLa and hepatoma cell cultures with normal cysteine levels (420nmol/mL) compared to control cell cultures, whereas lipoic acid and mercury ions strongly increased total glutathione in both types of cell cultures. Lower amount of total glutathione was observed in cell cultures with a lower cysteine levels (84nmol/mL), which is similar to that in human plasma. A strongly decreased total amount of glutathione in the presence of copper ions was observed in hepatoma cell cultures with lower cysteine levels, whereas the other agents showed effects similar to those described for cell cultures with normal cysteine levels.
Answer: Glutathione synthesis in hepatoma cell cultures is probably more sensitive to a low cysteine level than HeLa cell cultures, and the presence of copper ions further decreases the availability of cysteine probably by increasing the disulfide binding to cysteine residues in extracellular proteins, which causes a further decrease of total glutathione.

SOLUTION: Do traces of copper ions deplete glutathione in human hepatoma cell cultures with low cysteine content?

PROBLEM: Context: Population-referenced total activity counts per day (TAC/d) percentiles provide public health practitioners a standardized measure of physical activity (PA) volume obtained from an accelerometer that can be compared across populations. The purpose of this study was to describe the application of TAC/d population-referenced percentiles to characterize the PA levels of population groups relative to US estimates.', 'A total of 679 adults participating in the 2011 NYC Physical Activity Transit survey wore an ActiGraph accelerometer on their hip for seven consecutive days. Accelerometer-derived TAC/d was classified into age- and gender-specific quartiles of US population-referenced TAC/d to compare differences in the distributions by borough (N=5).', 'Males in Brooklyn, Manhattan, and Staten Island had significantly greater TAC/d than US males. Females in Brooklyn and Queens had significantly greater levels of TAC/d compared to US females. The proportion of males in each population-referenced TAC/d quartile varied significantly by borough (χ(2)(12)=2.63, p=0.002), with disproportionately more men in Manhattan and the Bronx found to be in the highest and lowest US population-referenced TAC/d quartiles, respectively. For females, there was no significant difference in US population-reference TAC/d quartile by borough (χ(2)(12)=1.09, p=0.36).
Answer: These results demonstrate the utility of population-referenced TAC/d percentiles in public health monitoring and surveillance. These findings also provide insights into the PA levels of NYC residents relative to the broader US population, which can be used to guide health promotion efforts.

SOLUTION:
Does use of population-referenced total activity count percentiles to assess and classify physical activity of population groups?