Pulmonary Artery Banding for Congenitally Corrected Transposition of the Great Arteries With Hydrops Fetalis: A Case Report.

At 32 weeks of gestation, a male fetus with congenitally corrected transposition of the great arteries developed hydrops fetalis caused by a combination of mitral valve regurgitation and tricuspid valve regurgitation (TR). We performed a pulmonary artery banding (PAB) at 108 days old for gradually progressing TR, after confirming that a balloon dilatation test in the main pulmonary artery reduced TR. As the patient grew, the PAB became tighter and systolic blood pressure in the morphological left ventricle increased. At present, the patient is waiting for a double switch operation.

Respiratory syncytial virus shedding by children hospitalized with lower respiratory tract infection.

Children with respiratory syncytial virus (RSV) infection shed virus for variable periods. The aim of this study was to quantify the viral load in nasopharyngeal aspirates of children with RSV throughout their hospitalization. This study included 37 children who were admitted with a diagnosis of RSV infection based on a positive rapid diagnostic test. Nasopharyngeal aspirates were collected from patients every day, from admission to discharge. Viral detection and quantification were performed using quantitative real-time PCR. Of the 37 patients, RSV-A was detected in 29 and RSV-B in 6. Two patients were PCR-negative for any type of RSV. RSV-A was detected in 12 of 16 patients (75%) 6 days after admission. These patients shed detectable virus from days 1 to 12, and for a significantly longer period (mean 5.7 days) than RSV-B (mean 3.8 days) patients. Half of the RSV-A patients were also positive on day 14 following onset. RSV-A was detected in patients <12 months of age for significantly longer periods after onset than in patients ≥12 months of age. RSV-A viral load was negatively correlated with days from admission and days from onset. Because RSV shedding was frequently prolonged, the hospitalized children may have contracted RSV as a nosocomial infection. To prevent nosocomial RSV infections in hospital wards, healthcare workers must take appropriate infection control measures and provide adequate guidance on hand washing to the family of the patient.

Phosphatidylcholine-Mediated Aqueous Diffusion of Cellular Cholesterol Down-Regulates the ABCA1 Transporter in Human Skin Fibroblasts.

ATP-binding cassette protein A1 (ABCA1) is a cholesterol transporter that contributes to the active transport/removal of excess cellular cholesterol. ABCA1 expression is up-regulated when cells accumulate cholesterol. AIMS: The purpose of this study was to determine any correlation between extracellular phospholipid levels and ABCA1 expression and function. METHODOLOGY: Human foreskin fibroblasts were incubated with cholesterol alone or cholesterol and phosphatidylcholine. Total RNA was isolated and subjected to end-point RT-PCR to compare ABCA1 transcript levels. Cell lysates were subjected to Western blot analysis to compare ABCA1 protein levels. Cells were loaded with radiolabeled cholesterol and cellular cholesterol efflux was measured in the presence and absence of apoE, a cholesterol acceptor. ApoE-dependent efflux was calculated as a measure of ABCA1-mediated efflux. RESULTS: Here we show that incubation of cholesterol-loaded human skin fibroblasts with L-α-phosphatidylcholine (PC) decreases ABCA1 mRNA and protein levels by 93% and 57%, respectively, compared to cells loaded with cholesterol alone. Similarly, PC treatment results in a 25% reduction in ABCG1 mRNA levels compared to cells treated with cholesterol alone, but there is no change in SR-BI transcript levels. Subsequent incubation of phospholipid-treated cells with a cholesterol acceptor such as apoE for 24 hours shows a 65% reduction in ABCA1-mediated cholesterol efflux compared to efflux in cells not treated with PC. During the lipid treatment itself, there is a 2.7-fold greater loss of cholesterol from PC treated cells compared to cells treated with cholesterol alone. Measurement of cholesterol in cellular lipid extracts reveals that cells incubated in the presence of phosphatidylcholine are significantly depleted of cholesterol having only 20% of the cholesterol compared to cells loaded with cholesterol alone. CONCLUSION: Thus, phosphatidylcholine facilitates removal of cellular cholesterol, thereby negating the cholesterol-dependent induction of ABCA1 message, protein and function.

Down-regulation of lipoprotein lipase increases ABCA1-mediated cholesterol efflux in THP-1 macrophages.

The ATP-binding cassette transporter A1 (ABCA1) mediates the efflux of excess cholesterol from foam cells to lipid-poor apolipoprotein A-I, in a process called reverse cholesterol transport. Lipoprotein lipase (LPL) is a lipolytic enzyme expressed by macrophages within atherosclerotic lesions. Lentivirus-mediated RNA interference was used to genetically knock-down (KD) the expression of LPL in THP-1 macrophages. Silencing of the LPL gene was confirmed by end-point PCR, real time PCR, and protein analysis. Suppression of LPL expression correlated with a 1.6-fold up-regulation of ABCA1 mRNA levels, and resulted in a 4.5-fold increase in ABCA1-dependent cholesterol efflux. Replenishing LPL by addition of purified bovine LPL to the cell culture media resulted in down-regulation of ABCA1-mediated cholesterol efflux in both wild-type and LPL knockdown cells. These findings suggest an inverse correlation between macrophage LPL levels and ABCA1 cholesterol transport activity.