Given a passage with a context and an answer, 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.

Input: Consider Input: 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.
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.

Output: Does endotoxin stimulate arginine transport in pulmonary artery endothelial cells?


Input: Consider Input: Context: Complications after immediate breast reconstruction pose a significant challenge to the reconstructive surgeon. Known risk factors include smoking, obesity, age, and adjuvant oncologic therapies. Less is known about the association between axillary lymph node dissection (ALND) and the development of postoperative complications.', 'We conducted a retrospective study of all patients who underwent immediate breast reconstruction after mastectomy at our institution over a 10-year period. Our outcome was an occurrence of a major complication within 90 days postoperatively. For each patient, we recorded data on demographics, smoking status, pertinent medical history, reconstruction type, adjuvant chemotherapy and radiation, tumor pathology, and whether an ALND was performed. Odds ratios (OR) were calculated to estimate the risk of a complication if an ALND was performed.', 'One hundred eighty-four women, with 270 surgically treated breasts, were identified as having mastectomy with immediate reconstruction between 2002 and 2012. Mean age was 49.4 years (range, 25-84 years). There were 71 mastectomies with ALND performed, with 22 complications, and 199 mastectomies without ALND, with 20 complications (31% complication rate vs 10%, respectively; OR, 3.84; P < 0.001). When adjusted for reconstruction type, smoking history, obesity, age, presence of invasive disease, chemotherapy, and radiation therapy, the OR for complications was 3.49 (P < 0.01). The most common complication was infection in both groups.
Answer: Mastectomy with ALND is associated with a 3-fold increase in risk of major complications in women undergoing immediate breast reconstruction, even after adjustment for known risk factors and confounders. Further studies are warranted to elucidate how ALND leads to these complications and what measures can reduce their occurrence.

Output: Does axillary Lymph Node Dissection be a Risk Factor for Major Complications After Immediate Breast Reconstruction?


Input: Consider Input: Context: The aim of this study was to determine whether the diagnostic yield of thyroid fine-needle aspirations (FNAs) changes over the course of residency training.', 'We identified 5418 ultrasound-guided thyroid nodule FNAs performed in our radiology department from 2004 through 2012. For each FNA, we recorded if the FNA was performed by a resident and if so the name of the resident and supervising attending radiologist. For each resident, we determined the level of training based on their graduation year from our residency program and the date of the FNA as well as prior surgical training and if they completed subsequent interventional radiology fellowship. Pathology reports were reviewed, and FNAs were classified as diagnostic or nondiagnostic (ND). Generalized mixed models were used to assess ND rate with postgraduate years, including residents with and without prior surgical training or if they subsequently completed an interventional radiology fellowship.', 'Of the 5418 thyroid FNAs, 3164 (58.4%) were performed by a radiology resident under the direct supervision of an attending physician. There was a significant decrease in ND rate as postgraduate years increased (P < .05). A significant decrease in ND rate was found as postgraduate years increased for residents without prior surgical training (P = .0007) or subsequent training in interventional radiology (P = .0014); however, no significant decrease was found for residents with surgical training (P = .37) or completing an interventional radiology fellowship (P = .08). In addition, no significant difference was found for ND rate between postgraduate year 4 (PGY4) and PGY5 (P > .05).
Answer: ND thyroid FNA rates progressively decrease with training level, suggesting that early and continued participation in procedures throughout residency improves outcomes. This is particularly true for residents without prior surgical training or subsequent interventional radiology fellowship.


Output: Does resident experience increase diagnostic rate of thyroid fine-needle aspiration biopsies?