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.

[EX Q]: Context: Critically ill preterm and term neonates are at high risk for negative iron balance due to phlebotomy that occurs with frequent laboratory monitoring, and the high iron demand of rapid growth. Understanding the prioritization of iron between red blood cells (RBCs) and brain is important given iron's role in neurodevelopment.", 'Ten neonatal twin lamb pairs (n = 20) underwent regular phlebotomy for 11 d. Lambs were randomized to receive no iron or i.v. daily iron supplementation from 1 to 5\u2009mg/kg. Serum hemoglobin concentration and reticulocyte count were assayed, iron balance calculated, and iron content of RBCs, liver, brain, muscle, and heart measured at autopsy.', 'Among phlebotomized lambs: (i) liver iron concentration was directly related to net iron balance (r = 0.87; P < 0.001) and (ii) brain iron concentration was reduced as a function of net iron balance (r = 0.63) only after liver iron was depleted. In animals with negative iron balance, total RBC iron was maintained while brain iron concentration decreased as a percentage of the iron present in RBCs (r = -0.70; P < 0.01) and as a function of reticulocyte count (r = -0.63; P < 0.05).\Question: Is iron prioritized to red blood cells over the brain in phlebotomized anemic newborn lambs?
[EX A]: Phlebotomy-induced negative iron balance limits iron availability to the developing brain.

[EX Q]: Context: During reactive hyperemia, the brachial artery in some individuals constricts prior to dilation. Our aim was to describe the frequency of high-flow-mediated constriction (H-FMC) in adults, and its relationship to body composition and biomarkers of cardiovascular and metabolic risk.', 'Two hundred forty-six adults (124 male, 122 female; 36\u2009±\u20097 years old) were assessed for H-FMC via sonographic imaging of the brachial artery. Blood pressure, glucose, insulin, lipids, and body composition assessed via dual energy X-ray absorptiometry were collected. H-FMC was characterized as a 10-second average of maximal postocclusion constriction. Independent t test was used to compare H-FMC versus non-H-FMC individuals.', 'H-FMC was observed in approximately 69% of adult participants (54 obese, 57 overweight, and 59 normal weight). Total body mass (82.3\u2009±\u200917.5 versus 76.3\u2009±\u200916.3 kg, p\u2009=\u20090.012), fat mass (27.7\u2009±\u200911.5 versus 23.8\u2009±\u200910.5 kg, p\u2009=\u20090.012), body mass index (27.7\u2009±\u20094.9 versus 26.1\u2009±\u20095.0 kg/m\Question: Is high-flow-mediated constriction in adults influenced by biomarkers of cardiovascular and metabolic risk?
[EX A]: Increased body mass, fat mass, and body mass index were associated with a greater H-FMC. When H-FMC was present, the FMD response to reactive hyperemia was significantly lower. Because H-FMC has been observed to negatively affect FMD response to reactive hyperemia, we suggest that H-FMC should be noted when analyzing and interpreting FMD data. H-FMC may be an ancillary measure of endothelial health. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound, 2016.

[EX Q]: Context: Bruton's tyrosine kinase (Btk) is required for B lymphocyte and myeloid cell contributions to pathology in murine models of arthritis. Here, we examined the potential contributions of synovial Btk expression and activation to inflammation in rheumatoid arthritis (RA).", 'Btk was detected by immunohistochemistry and digital image analysis in synovial tissue from biologically naive RA (n=16) and psoriatic arthritis (PsA) (n=12) patients. Cell populations expressing Btk were identified by immunofluorescent double labelling confocal microscopy, quantitative (q-) PCR and immunoblotting. The effects of a Btk-specific inhibitor, RN486, on gene expression in human macrophages and RA synovial tissue explants (n=8) were assessed by qPCR, ELISA and single-plex assays.', 'Btk was expressed at equivalent levels in RA and PsA synovial tissue, restricted to B lymphocytes, monocytes, macrophages and mast cells. RN486 significantly inhibited macrophage IL-6 production induced by Fc receptor and CD40 ligation. RN486 also reduced mRNA expression of overlapping gene sets induced by IgG, CD40 ligand (CD40L) and RA synovial fluid, and significantly suppressed macrophage production of CD40L-induced IL-8, TNF, MMP-1 and MMP-10, LPS-induced MMP-1, MMP-7 and MMP-10 production, and spontaneous production of IL-6, PDGF, CXCL-9 and MMP-1 by RA synovial explants.\Question: Does btk inhibition suppress agonist-induced human macrophage activation and inflammatory gene expression in RA synovial tissue explants?
[EX A]:
Btk is expressed equivalently in RA and PsA synovial tissue, primarily in macrophages. Btk activity is needed to drive macrophage activation in response to multiple agonists relevant to inflammatory arthritis, and promotes RA synovial tissue cytokine and MMP production. Pharmacological targeting of Btk may be of therapeutic benefit in the treatment of RA and other inflammatory diseases.