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: Ascent to high altitude leads to a reduction in ambient pressure and a subsequent fall in available oxygen. The resulting hypoxia can lead to elevated pulmonary artery (PA) pressure, capillary stress, and an increase in interstitial fluid. This fluid can be assessed on lung ultrasound (LUS) by the presence of B-lines. We undertook a chamber and field study to assess the impact of high-intensity exercise in hypoxia on the development of pulmonary interstitial edema in healthy lowlanders.', 'Thirteen volunteers completed a high-intensity intermittent exercise (HIIE) test at sea level, in acute normobaric hypoxia (12% O2, approximately 4090 m equivalent altitude), and in hypobaric hypoxia during a field study at 4090 m after 6 days of acclimatization. Pulmonary interstitial edema was assessed by the evaluation of LUS B-lines.', 'After HIIE, no increase in B-lines was seen in normoxia, and a small increase was seen in acute normobaric hypoxia (2 ± 2; P < .05). During the field study at 4090 m, 12 participants (92%) demonstrated 7 ± 4 B-lines at rest, which increased to 17 ± 5 immediately after the exercise test (P < .001). An increase was evident in all participants. There was a reciprocal fall in peripheral arterial oxygen saturations (Spo2) after exercise from 88% ± 4% to 80% ± 8% (P < .01). B-lines and Spo2 in all participants returned to baseline levels within 4 hours.\Question: Does high-intensity intermittent exercise increase pulmonary interstitial edema at altitude but not at simulated altitude?

SOLUTION: HIIE led to an increase in B-lines at altitude after subacute exposure but not during acute exposure at equivalent simulated altitude. This may indicate pulmonary interstitial edema.

PROBLEM: Context: Eradication of Helicobacter pylori is not routinely recommended for the symptomatic relief and the prevention of gastric cancer in patients with functional dyspepsia. The present study investigated a useful indicator of H. pylori eradication in such patients by determining the optimal cutoff value of a 13C-urea breath test (UBT).', 'One hundred dyspeptic patients participated in the study. Dyspepsia was scored, and a 13C-UBT administered. A level of delta 13C-UBT of>4 per thousand was diagnosed as H. pylori-positive. After the stomach was endoscopically sprayed with phenol red, biopsy specimens were taken from the antrum, body and cardia of the stomach for the assessment of H. pylori density, and activity (neutrophil infiltration) and degree (lymphocyte infiltration) of gastritis.', 'Correlation between delta 13C-UBT and dyspepsia score was not found. Delta 13C-UBT significantly correlated with H. pylori density score in the total stomach (r = 0.53, P < 0.0001), neutrophil (r = 0.34, P = 0.0005) and lymphocyte score (r = 0.69, P < 0.0001). Twenty-six of the 100 subjects had a neutrophil score of >or=4, lymphocyte score of >or=4, and H. pylori score of >or=4. Their 95% confidence interval of mean was 58.2 per thousand, which reflects moderate to marked acute and chronic gastritis, and dense H. pylori colonization.\Question: Is delta ( 13 ) C-urea breath test value a useful indicator for Helicobacter pylori eradication in patients with functional dyspepsia?

SOLUTION: The 13C-UBT is a reliable semiquantitative test to assess H. pylori density and the activity and degree of gastritis. It is proposed that H. pylori eradication therapy might be beneficial for patients with functional dyspepsia with a delta 13C-UBT of >58.2 per thousand.

PROBLEM: Context: 5-year survival for melanoma metastasis to regional lymph nodes (American Joint Committee on Cancer stage III) is <50%. Knowledge of outcomes following therapeutic lymphadenectomy for stage III melanoma related to BRAF status may guide adjuvant use of BRAF/MEK inhibitors along with established and future therapies.', 'To determine patterns of melanoma recurrence and survival following therapeutic lymph node dissection (TLND) associated with oncogenic mutations.', 'DNA was obtained from patients who underwent TLND and had ⩾2 positive nodes, largest node >3cm or extracapsular invasion. Mutations were detected using an extended Sequenom MelaCARTA panel.', 'Mutations were most commonly detected in BRAF (57/124 [46%] patients) and NRAS (26/124 [21%] patients). Patients with BRAF mutations had higher 3-year recurrence rate (77%) versus 54% for BRAF wild-type patients (hazard ratio (HR) 1.8, p=0.008). The only prognostically significant mutations occurred in BRAF: median recurrence-free (RFS) and disease-specific survival (DSS) for BRAF mutation patients was 7 months and 16 months, versus 19 months and not reached for BRAF wild-type patients, respectively. Multivariate analysis identified BRAF mutant status and number of positive lymph nodes as the only independent prognostic factors for RFS and DSS.\Question: Is bRAF mutation status an independent prognostic factor for resected stage IIIB and IIIC melanoma : implications for melanoma staging and adjuvant therapy?

SOLUTION:
Patients with BRAF mutations experienced rapid progression of metastatic disease with locoregional recurrence rarely seen in isolation, supporting incorporation of BRAF status into melanoma staging and use of BRAF/MEK inhibitors post-TLND.