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.

Context: Hypertrophic cardiomyopathy (HCM) is associated with myocardial scarring and ventricular tachycardia (VT). Contrast-enhanced cardiac magnetic resonance imaging (CE-CMR) can quantify myocardial scar, and scar imaging has been documented in patients with HCM. We investigated the assessment of myocardial scar in HCM patients using CE-CMR, and its correlation with proven VT.', 'Twenty-five patients (mean age 54 +/- 8) with HCM who underwent CE-CMR were identified, and clinical data obtained from chart review. Parameters of LV function were calculated from cine imaging, and myocardial scar was assessed using delayed enhancement imaging following gadolinium administration.', 'Myocardial scar was detected in 16 (64%) patients with a mean mass 9 +/- 15 g. Scar was patchy, mid-myocardial and located in the basal anteroseptum, and RV insertion sites. Scar was seen in septal, apical and concentric variants of HCM. Scar mass correlated with both LV Mass (r2 = 0.74) and maximal LV wall thickness (r2 = 0.42). VT occurred in 32% of patients, and was associated with both increased scar mass and wall thickness compared to non-VT patients (21 +/- 22 g vs. 4 +/- 6 g, and 2.4 +/- 0.5 cm vs. 1.8 +/- 0.5 cm, p < 0.05). LV size and function were similar in patients with and without VT. A scar mass of >7 g predicted the presence of VT with a sensitivity of 75% and specificity 82%.
Answer: Myocardial scar imaged by CE-CMR is common in patients with HCM, and is predictive of VT. Scar is seen in all HCM variants, and is associated with maximal wall thickness. There may be a role for CE-CMR in improved risk stratification for individual patients with HCM.
Is myocardial scar detected by contrast-enhanced cardiac magnetic resonance imaging associated with ventricular tachycardia in hypertrophic cardiomyopathy patients?

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.
Does endotoxin stimulate arginine transport in pulmonary artery endothelial cells?

Context: Immunologic abnormalities have been found in bipolar disorder but pentraxin 3, a marker of innate immunity, has not been studied in this population.', 'Levels of pentraxin 3 were measured in individuals with bipolar disorder, schizophrenia, and non-psychiatric controls. Linear regression models were used to compare the pentraxin 3 levels in each of the psychiatric groups to that in the control group, adjusting for demographic and clinical variables. Logistic regression models were used to calculate the odds ratios associated with levels of pentraxin 3 which differed from specified levels of the control group.', 'The sample consisted of 831 individuals: 256 with bipolar disorder, 309 with schizophrenia, and 266 without a psychiatric disorder. The levels of pentraxin 3 in the bipolar disorder, but not in the schizophrenia, group were significantly lower than those of controls, adjusting for age, gender, race, maternal education, smoking status, and body mass index (t = -3.78, p < 0.001). The individuals with bipolar disorder also had significantly increased odds of having low levels of pentraxin 3 relative to both the 10th and 25th percentile level of the controls and significantly decreased odds of having a level greater than the 75th and the 90th percentile level of the controls, adjusting for the same covariates.
Answer: Individuals with bipolar disorder have low levels of pentraxin 3 which may reflect impaired innate immunity. An increased understanding of the role of innate immunity in the etiopathogenesis of bipolar disorder might lead to new modalities for the diagnosis and treatment of this disorder.

Is pentraxin 3 reduced in bipolar disorder?