instruction:
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.
question:
Context: The pulmonary endothelium plays an important role in the metabolism of the amino acid arginine, the exclusive precursor molecule for nitric oxide (NO). Despite decreased circulating arginine levels, endothelial NO production is elevated during endotoxemia. However, the regulation of pulmonary artery endothelial arginine transport has not been studied. We hypothesized that endotoxin stimulates carrier-mediated arginine transport by the pulmonary endothelium.', 'The relative contributions of the various transport systems to total arginine transport by porcine pulmonary artery endothelial cells (PAECs) was determined by assaying the uptake of 3H-L-arginine in the presence or absence of Na+. PAECs were then incubated with various concentrations of Escherichia coli endotoxin, and y(+)-mediated arginine transport was measured at different time points thereafter. Kinetic studies were performed over a range of arginine concentrations to determine changes in transport affinity and maximum rate of metabolism. To address the role of RNA and protein synthesis in the increased transport, uptake was measured after exposure of cells to the transcriptional inhibitor actinomycin D and the protein synthesis inhibitor cycloheximide.', 'Most (75%) of arginine transport by PAECs was mediated by the high-affinity Na(+)-independent transport system y+. Endotoxin stimulated y(+)-mediated arginine transport by PAECs twofold to fivefold, a response that was time and dose dependent. The accelerated transport was detectable within 2 hours and maximal at 12 hours. Kinetic studies revealed that the accelerated arginine transport was the result of a 68% increase in the maximal transport velocity (1519 +/- 65 pmol/mg protein/30 sec in endotoxin-treated cells vs 903 +/- 96 in control cells; p < 0.01) without a change in transport affinity. The endotoxin-mediated increase in arginine uptake was abrogated by actinomycin D and cycloheximide.\Question: Does endotoxin stimulate arginine transport in pulmonary artery endothelial cells?
answer:
Endotoxin stimulates Na(+)-independent arginine transport by PAECs through a process that requires de novo RNA and protein synthesis, possibly of the transporter itself. This response may be designed to support arginine-dependent biosynthetic pathways in the lung during septic states.

question:
Context: To compare the efficacy and safety of prophylactic modalities for heterotopic ossification prevention after elbow and acetabular surgeries.', 'The retrospective chart review was conducted at the Aga Khan University Hospital and comprised record of patients who underwent open reduction and internal fixation for elbow and acetabular fractures between 2010 and 2013. Data was classified into three groups: Group A patients had received single dose of radiotherapy; Group B patients had received indomethacin, and Group C patients had not received any prophylaxis. Outcome variables included time-to-fracture healing, heterotopic ossification, non-union and wound infection.', 'Of the 104patients 70(67.3%) had elbow fractures and 34(32.7%) had acetabular fractures. Out of the 70patients with elbow fractures, 28(27%) were in Group A, 24(23%) in Group B, and 18(17%) in Group C. In Group A, 4(22%) patients had wound infection compared to 1(5.5%) patient in Group C (p=0.131). One (4%) patient in Group B and 1(5.5%) in Group C developed heterotopic ossification (p=0.486). Non-union occurred in 1(4%) patient in Group B and 1(5.5%) in Group C. Out of the 34 patients with acetabular fractures, 11(32.3%) were in Group A, 10(29.4%) in Group B, and 13(38.2%) in Group C. In Group A, 2(18.2%) patients developed wound infection. Only 1(7.6%) patient in Group C developed heterotopic ossification.\Question: Do prophylaxis against heterotopic ossification after elbow and acetabular fractures - Do we really need it?
answer:
No role of radiotherapy or indomethacin was detected in the prevention of heterotopic ossification.

question:
Context: To determine the effect of infusion with a dual-binding antibody to E- and L-selectin, EL-246, in a postonset model of sepsis.', 'Nonrandomized controlled study.', 'Young Yorkshire swine.', 'Three groups were studied. Controls (n = 8) received saline solution only. Untreated animals with sepsis (n = 8) received a 1-hour intravenous infusion of live Pseudomonas aeruginosa. Animals treated with EL-246 (n = 6) received the same bacterial infusion and a 2-mg/kg bolus of EL-246 at 30 minutes.', 'Systemic and pulmonary hemodynamics, arterial blood gas determination, bronchoalveolar lavage protein and neutrophil content, neutrophil integrin and selectin expression, neutrophil oxidant burst, and organ myeloperoxidase content.', 'Treatment with EL-246 significantly reduced lung injury, as indicated by improved bronchoalveolar lavage protein and neutrophil content, resulting in a significant improvement in arterial oxygenation. This reduction in lung injury was produced by a reduction in lung myeloperoxidase content. Treatment with EL-246 failed to prevent the development of pulmonary hypertension and systemic hypotension. Neutrophils from animals with sepsis exhibited significant activation and upregulation of CD18, shedding of L-selectin, and production of increased levels of oxidants compared with controls.\Question: Is sepsis-induced acute lung injury attenuated by selectin blockade following the onset of sepsis?
answer:
Treatment of animals with EL-246 soon the onset of sepsis produced significant protection against acute lung injury but failed to attenuate hemodynamic derangements associated with sepsis.