TASK DEFINITION: In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
PROBLEM: Context: Aging is associated with reduced secretion of, and down-regulation of receptors for, progesterone (P); yet, P's effects when administered to younger and older animals have not been systematically investigated. Some of P's antianxiety effects may be due to its conversion to 3alpha-hydroxy-5alpha-pregnan-20-one (3alpha,5alpha-THP) and its subsequent actions as a positive modulator at GABAA receptor complexes (GBRs).", 'We investigated whether P administration can decrease anxiety behavior of progestin receptor (PR) knockout (PRKO) or wild-type control mice.', 'P (10 mg/kg) or vehicle (propylene glycol) were administered subcutaneously to intact, female or male wild-type or PRKO mice that were either 9-12 or 18-24 months of age. Behavior in tasks that assess spontaneous activity (activity monitor and roto-rod), free exploration of a novel environment (open field, elevated plus maze, and elevated zero maze), and conflict behavior (mirror chamber, dark-light transition, and punished drinking) were examined 1 h after injection.', 'P significantly decreased anxiety behavior of both PRKO and wild-type mice. P did not alter motor behavior but increased central entries in the open field, time in the open quadrants of the elevated zero maze, time in the mirrored chamber, time in the light compartment of the dark-light transition, and punished drinking in young and old mice. P-administered mice had higher levels of hippocampal 3alpha,5alpha-THP and GABA-stimulated chloride flux than did vehicle-administered PRKO or wild-type mice.\Question: Do progesterone 's effects to reduce anxiety behavior of aged mice require actions via intracellular progestin receptors?

SOLUTION: The effects of P to decrease anxiety behavior of younger and older mice do not require classic PRs and may involve actions of 3alpha,5alpha-THP at GBRs.

PROBLEM: Context: This study investigated whether anxiety, fear of pain, or pain catastrophizing were predictive of pain-related outcomes after induced delayed onset muscle soreness (DOMS) at the shoulder.', 'Healthy participants (19 males and 23 females) were eligible for participation if they had (a) no history of neck or shoulder pain, (b) no sensory or motor impairments of the upper-extremity, (c) not regularly participating in upper-extremity weight training, (d) not currently or regularly taking pain medication, and (e) no history of upper-extremity surgery. Participants completed self-report measures for fear of pain, pain catastrophizing, and anxiety. Then, participants underwent a standard fatigue protocol to induce DOMS in the shoulder external rotator muscles. Participants were reassessed 24 hours after DOMS induction on clinical and evoked pressure pain reports, muscle force production, self-report of upper-extremity disability, and kinesiophobia. Stepwise regression models considered sex, anxiety, pain intensity, fear of pain, and pain catastrophizing as outcome predictors.', 'Fear of pain alone explained 16% (P=0.008) of the variance in clinical pain and 10% (P=0.047) evoked pressure pain intensity. Clinical pain intensity alone explained 11% (P<0.031) of the variance in muscle force production. Clinical pain intensity and fear of pain explained 50% (P<0.001) of the variance in upper-extremity disability, whereas fear of pain and sex accounted for 26% (P=0.005) of the variance in kinesiophobia.\Question: Does fear of pain influence outcomes after exercise-induced delayed onset muscle soreness at the shoulder?

SOLUTION: With the exception of muscle force production, fear of pain had a consistent influence on shoulder DOMS outcomes, even after controlling for pain intensity. This study suggests fear of pain may be a relevant psychologic factor to consider in clinical studies investigating the development and treatment of chronic shoulder pain.

PROBLEM: 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).\Question: Does early heart rate recovery after exercise predict mortality in patients with chronic heart failure?

SOLUTION:
Early heart rate recovery is an independent prognostic risk indicator in CHF patients and could be used in CHF risk stratification.