TASK DEFINITION: Given a passage, 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: The effects of exercise training on nocturnal blood pressure (BP) dipping status remain unclear. African Americans have the highest prevalence of nondippers compared with other racial/ethnic populations. In this 6-month study we tested the hypothesis that long-term aerobic exercise training would increase the levels of nocturnal BP dipping in African American nondippers.', 'We recruited African Americans who were nondiabetic, nonsmoking, and free from cardiovascular and renal disease. For this analysis, only African Americans with a nondipping profile, defined as those with the absence of a nocturnal decline in systolic or diastolic BP (<10% of daytime values), which was determined by ambulatory BP monitoring, were chosen. A pre-post design was used, with baseline and final evaluation including office blood pressure measurement, 24-h ambulatory blood pressure monitoring, fasted blood sampling, and graded exercise testing. Participants engaged in 6 months of supervised aerobic exercise training (AEXT). Following the AEXT intervention, there were significant increases in systolic BP dipping (baseline: 5.83.9% vs. final: 9.46.1%, P=0.0055) and pulse pressure dipping (baseline: -3.16.6% vs. final: 5.012.8%, P=0.0109). Of the 18 participants with a nondipping profile at baseline, eight were nonclassified as nondippers after the AEXT intervention. There were no significant changes in office systolic BP/diastolic BP values following the AEXT intervention.

SOLUTION: Does chronic aerobic exercise improve blood pressure dipping status in African American nondippers?

PROBLEM: Bone and antler collagen (13) C and (15) N values are often assumed to be equivalent when measured in palaeodietary, palaeoclimate and palaeocological studies. Although compositionally similar, bone grows slowly and is remodelled whereas antler growth is rapid and remodelling does not occur. These different patterns of growth could result in isotopic difference within antler and between the two tissue types. Here we test whether red deer (Cervus elaphus) bone and antler (13) C and (15) N values are equivalent, and whether intra-antler isotopic values are uniform.', 'Bone and antler were isotopically analysed from six stags that lived in a temperate maritime climate on the Isle of Rum, Scotland. Multiple antlers from different years were sampled per individual, together with a single bone sample per individual. Up to 12 samples were taken along the length of each antler (total of 25 antlers, 259 samples) so that a chronological record of the isotopic composition during antler growth could be obtained. Collagen was extracted and its (13) C and (15) N values were measured by continuous-flow isotope ratio mass spectrometry.', 'Intra-antler collagen isotope signatures vary, and show that not all antlers from an individual or a growth year are equivalent in carbon and nitrogen isotopic ratios. (15) N values typically increase with distance along antler length, but no overall trend is observed in (13) C values. An isotopic offset is visible between bone and antler, with bone (13) C and (15) N values being higher in most cases.

SOLUTION: Are red deer bone and antler collagen isotopically equivalent in carbon and nitrogen?

PROBLEM: Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive and easily tolerated method of altering cortical physiology. To date, numerous open and sham controlled clinical trials have explored the antidepressant potential of rTMS. In the present study, we investigated clinical trials of high-frequency rTMS (20 Hz) for treatment of refractory depression, and also examined the effect of rTMS on plasma levels of catecholamine metabolites and brain-derived neurotropic factor (BDNF).', 'Twenty-six depressed inpatients who met the DSM-IV criteria for major depressive disorder and had failed to respond to treatment with at least two antidepressant drugs given at adequate doses (above 150 mg/day in an equivalent dose of imipramine) and durations (at least 4 weeks for each drug) were enrolled in this study. Eleven were males, 15 females. The ages of the subjects ranged from 19 to 78 years old (mean +/- SD = 52.9 +/- 17.8). All patients were administered left prefrontal 20 Hz rTMS at 80 % MT (total 800 pulses a day) over ten daily sessions. The plasma levels of 3-methoxy-4-hydroxyphenylglycol (MHPG) and homovanillic acid (HVA) were analyzed by high-performance liquid chromatography. The plasma levels of BDNF were also measured with the sandwich ELISA method.', 'The mean 17-item Hamilton Rating Scale for Depression (Ham-D) score of 20.5 +/- 5.2 before rTMS was significantly decreased to 15.6 +/- 7.3 after rTMS. Nine of 26 patients (35 %) demonstrated some improvement (Ham-D > or = 25 %) by rTMS. The levels of plasma MHPG, but not those of HVA, were significantly reduced after rTMS treatment, and a negative correlation was observed between the change in plasma MHPG levels and the change in scores of agitation. In addition, the plasma levels of BDNF were significantly increased by 23 % in responders and partial responders, but not in nonresponders, after rTMS treatment, and a trend for association was found between the changes in Ham-D scores and changes in plasma BDNF levels in all patients after rTMS treatment.

SOLUTION:
Does high-frequency repetitive transcranial magnetic stimulation improve refractory depression by influencing catecholamine and brain-derived neurotrophic factors?