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Background and Aim of the Study: Recent data have shown that aortic valve stenosis (AS) is an active and highly regulated process which shares similarities with atherosclerosis. However, AS cannot be considered as a purely atherosclerotic phenomenon, and a hypercholesterolemic rabbit model might not be fully representative of human AS pathophysiology., Methods: Twenty-eight New Zealand White rabbits were assigned to three groups: group 1 (no dietary supplement for three months); group 2 (0.3% cholesterol-enriched-diet + 50,000 IU/day vitamin D2 for six months); and group 3 (1% cholesterol-enriched-diet + vitamin D2 for three months). The peak aortic gradient and permeability index (outflow tract/aortic velocity-time-integral) were assessed, as well as calcium staining within the aortic valve and ascending aorta., Results: AS hemodynamic severity was not different among the groups. The peak gradient was 4 +/- 2 mmHg at baseline, 4 +/- 2 mmHg at three months in controls, 4 +/- 1 mmHg at three months and 6 +/-3 mmHg at six months in group 2, and 4 +/- 1 mmHg at three months in group 3 (p = NS). The permeability index was 64 +/- 7 at baseline, 60 +/- 12 at three months in controls, 63 +/- 14 at three months and 58 +/- 12 at six months in group 2, and 60 +/- 5 at three months in group 3 (p = NS). The aortic valve of cholesterol-enriched-diet rabbits was thickened but not calcified, whereas the ascending aorta was both thickened and calcified., Conclusion: When using a hypercholesterolemic rabbit model plus vitamin D2, no adverse hemodynamic effect or aortic valve calcification was observed, despite a high-level and prolonged cholesterol-regimen supplementation. These results raise questions with regard to the extrapolation of this animal model to humans.

Objective: To assess the predictive capacity for the diagnosis of ventilator-associated pneumonia (VAP) of serum procalcitonin levels before and on the day it is suspected., Design and Setting: Single-center observational study in the intensive care unit of a teaching hospital., Patients and Participants: Consecutive patients whose serum procalcitonin levels were available on the day that VAP was clinically suspected (day 1) and at some time within the preceding 5 days ("before")., Measurements and Results: Serum procalcitonin levels were determined on day 1 and "before". Among the 73 suspected episodes VAP was confirmed by quantitative bronchoalveolar lavage cultures in 32 and refuted in 41. Respective median "before" procalcitonin levels were 1.89 ng/ml (interquartile range 0.18-6.01) and 2.14 (0.76-5.75) in patients with and without VAP, but their respective median day-1 procalcitonin levels did not differ: 1.07 ng/ml (0.39-6.57) vs. 1.40 (0.67-3.39). On day 1 a 0.5 ng/ml procalcitonin threshold had 72% sensitivity but only 24% specificity for diagnosing VAP. Between "before" and day 1, procalcitonin increased in 41% and 15% of patients with and without VAP, respectively. Thus a procalcitonin rise on day 1, compared to its "before" level, had 41% sensitivity and 85% specificity for diagnosing VAP, with respective positive and negative predictive values of 68% and 65%., Conclusions: Crude values and procalcitonin rise had poor diagnostic value for VAP in this particular setting and thus should not be used to initiate antibiotics when VAP is clinically suspected.

In this study we analyze the impact of the patient's socioeconomic status (SES) and the distance from the patient's home to the dialysis center (DPH-DC), classified as < or =300 km or >300 km, on the patient and technique survival of 59 patients starting chronic peritoneal dialysis (CPD) between May 1983 and January 2004 at a single center in Uruguay. SES was established using Graffar's method. Mean duration of CPD was 38.1+/-26.0 months. Mean age at the start of CPD was 8.4+/-5.2 years. Overall patient and technique survival at 5 years were 86.4% and 77.9%, respectively. Twenty (33.8%) patients were transferred to hemodialysis. Eight (13.5%) patients died. The incidence of peritonitis was one episode every 9.1 months. There was no statistically significant difference in patient and technique survival between the patients in the low and high SES groups (p=0.72 and 0.99, respectively), and between those in the two DPH-DC groups, (p=0.22 and p=0.99, respectively). Logistic regression analysis confirmed low SES and DPH-DC >300 km are not predictors of patient death (p=0.79 and p=0.09, respectively) or technical failure (p=0.35 and p=0.15, respectively). No SES- and DPH-DC-related statistically significant differences were found in patient and technique survival.