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: Renal ischemia-reperfusion (I/R) injury is a major cause of acute renal failure (ARF). The transcription factor nuclear factor-kappaB (NF-kappaB) has been implicated as a key mediator of reperfusion injury. Activation of NF-kappaB is dependent upon the phosphorylation of its inhibitor, IkappaB, by the specific inhibitory kappaB kinase (IKK) subunit, IKKbeta. We hypothesized that ischemic preconditioning (IPC) reduces acute renal damage following I/R injury by inhibiting activation of IKKbeta. As neutrophil gelatinase-associated lipocalin (NGAL), an early predictive biomarker of acute kidney injury, is regulated by NF-kappaB, we approached the relationship between NGAL and IKKbeta.', 'Thirty male Sprague-Dawley rats were randomly divided into 3 groups after right kidney nephrectomy. Group A rats were sham-operated controls. Group B rats were 45-min ischemic in the left renal artery while Group C rats were pre-treated with 3 cycles of 2-min ischemia and 5-min reperfusion. All the rats were sacrificed at 24 h after reperfusion. We harvested kidneys and serum to do further analysis, including histological and functional parameters, expressions of NGAL and IKKbeta in renal tissues.', 'Compared with rats subjected to I/R injury, pre-treated rats had a significant decrease in serum creatinine level (Scr) and tubulointerstitial injury scores (Scr, 86.79 +/- 12.98 vs. 205.89 +/- 19.16 mircomol/l, p < 0.01; tubulointerstitial injury scores, 1.3 +/- 0.48 vs. 3.8 +/- 0.79, p < 0.01). In addition, expressions of IKKbeta (0.95 +/- 0.21 vs. 1.74 +/- 0.17, p < 0.05) and NGAL (1.71 +/- 0.032 vs. 2.66 +/- 0.078, p < 0.05) at renal tubule in pre-treated rats were attenuated significantly compared with rats subjected to ischemia-reperfusion injury. Moreover, our study showed that IKKbeta and NGAL were in positive correlation (R = 0.965 > R(0.01)(30) = 0.448, p < 0.01).
Answer: The evidence suggests that IKKbeta may play a role in renal I/R injury and give rise to the generation of NGAL. It appears that IPC may attenuate renal injury and the expression of NGAL following acute I/R injury. IKKbeta may offer a clinically accessible target for preventing renal injury following I/R.
Does ischemic preconditioning attenuate renal ischemia-reperfusion injury by inhibiting activation of IKKbeta and inflammatory response?

Context: Serum ghrelin levels are elevated in uremic patients. However, no data are available on the relationship between metabolic syndrome and serum ghrelin levels in peritoneal dialysis (PD) patients.', 'Metabolic syndrome and its components were defined using diagnostic criteria recommended by the International Diabetes Federation. Fasting serum samples were taken from 30 PD patients. Serum ghrelin levels were measured by using a commercial enzyme-linked immunosorbent assay kit.', 'Of the 30 PD patients, 53.3% (16/30) had metabolic syndrome. Fasting serum ghrelin corrected inversely with metabolic syndrome among these PDs patients (p = 0.002). By odds ratio (OR) analysis of metabolic syndrome and metabolic syndrome diagnostic criteria, the predictors for metabolic syndrome are fasting glucose [OR: 39.00; 95% confidence interval (CI): 3.80 to 399.85; p < 0.001], triglycerides (OR: 37.50; 95% CI: 3.64 to 386.51; p < 0.001), and waist circumference (OR: 4.20; 95% CI: 1.95 to 9.03; p < 0.001). Univariate linear regression analysis showed that body weight (r = -0.461, p = 0.010), waist circumference (r = -0.390, p = 0.033), and body mass index (r = -0.438, p = 0.016) were negatively correlated with serum ghrelin, and serum high density lipoprotein [HDL (r = 0.626, p < 0.001)] was positively correlated with serum ghrelin. Multivariate forward stepwise linear regression analysis of the significant variables showed that HDL (R(2) change = 0.392; p < 0.001) was the independent predictor of serum ghrelin in PD patients and explained 39.2% of the variance.
Answer: These results indicate an inverse association between circulating fasting ghrelin and metabolic syndrome in PD patients. Serum HDL was associated with serum ghrelin among PD patients.
Is fasting serum ghrelin level associated with metabolic syndrome in peritoneal dialysis patients?

Context: Increased triglyceride (TG) occurs in patients with acute coronary syndrome (ACS), and apolipoprotein AV (apoAV) has been shown to lower TG levels. In the present study, we investigated plasma apoAV level and its relationship with TG and C-reactive protein (CRP) in ACS patients.', 'A total of 459 subjects were recruited and categorized into control group (n = 116), stable angina (SA) group (n = 115), unstable angina group (n = 116) and acute myocardial infarction group (n = 112). Plasma apoAV level was measured by a sandwich ELISA assay.', 'Compared with controls ((100.27 +/- 22.44) ng/ml), plasma apoAV was decreased in SA patients ((76.54 +/- 16.91) ng/ml) but increased in patients with unstable angina ((330.89 +/- 66.48) ng/ml, P < 0.05) or acute myocardial infarction ((368.66 +/- 60.53) ng/ml, P < 0.05). Inverse correlations between apoAV and TG were observed in the control or stable angina groups (r = -0.573 or -0.603, respectively, P < 0.001), whereas positive correlations were observed in the patients with unstable angina or acute myocardial infarction (r = 0.696 or 0.690, respectively, P < 0.001). Furthermore, a positive relationship between apoAV and CRP was observed in the ACS patients but not in the non-ACS subjects.
Answer: The plasma apoAV concentration is increased and positively correlates with TG and CRP in ACS patients.

Is elevated plasma apolipoprotein AV in acute coronary syndrome positively correlated with triglyceride and C-reactive protein?