A. K. Ghafouripour

A higher blood flow window of reduced thrombogenicity and acceptable fragmentation in a hollow fiber hemodialyzer

: Body composition can have a significant effect on methods for estimating urea volume (V) and fractional clearance (KT/V) in patients with renal failure. These effects were examined in 27 men on continuous ambulatory peritoneal dialysis (CAPD). Urea volume was calculated as 0.6% of body weight (V.6), by the Watson formula (VW) and by the Hume formula (VH). Patients were classified as obese (> 120% of ideal body weight), normal (90%-120% of ideal weight), or wasted ( 1.70; five subjects had KT/VH 1.70; and two subjects had KT/V0.6 1.70. In the obese group, KT/V0.6 (1.62 +/- 0.67) was significantly less than KT/VW (1.93 +/- 0.76; p < 0.001) and KT/VH (1.92 +/- 0.78; p < 0.001). Fractional errors in V and KT/V between any two methods were highly correlated with percent deviation from ideal body weight (r = 0.81 or higher). In peritoneal dialysis patients, excessive body weight affects the estimates of V and KT/V urea by certain methods, and may lead to erroneous impressions about the adequacy of CAPD.

A New Direct Method of Cell-Labeling in Whole Blood by Administration of 111In Labeled Anti-Sense Oligonucleotide Probe: Evaluation of Radiolabeled Probes for Noninvasive Imaging of Inflammation and Infection

The antisense oligonucleotide probes were labeled with 111Indium for determination of metabolic fate by in vitro and in vivo systems. We optimized the conditions of the chelation e.g. concentration of reactants, pH, time and temperature. The 25-mer nucleotide sequence (sense and antisense) for histone4-mRNA was modified by coupling with aminohexyl group (AHON) and conjugated with DTPA-isothiocyanate (1/10); 50 μg, of DTPA-AHON were chelated with 37-370 MBq (1-10 mCi) of 111In chloride with high specific activity 30-100 μCi/μg and labeling efficiency (60-80)%. Incubation of radiolabeled probe with murine leukemic cells (P388) and neutrophils demonstrated probe-stability in plasma and minimum essential media and high permeability, cellular extraction and retention; 0.1 μg/ml of IN-AHON was found optimal for cell-labeling. The histone4 probe showed higher specificity for neutrophils than platelets and red cells. The blood-clearance in Beagle dogs and biodistribution studies in Yorkshire pigs were carried out after injection of In-AHON or In-AHON labeled neutrophils, imaged with a gamma camera and sacrificed for biodistribution; (75±5)% of radioactivity stayed in blood at 720 hours after injection. Margination in lung and pooling in spleen and liver were observed after injection of labeled neutrophils. These results suggested that cells in blood could be labeled directly and could be imaged non-invasively for blood-pool and infection.