S. Krishnasamy

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PURPOSE With on-line portal imaging devices and image registration tools, the verification of radiation field position prior to each treatment becomes technically feasible. In this paper, we analyze the impact of pre-treatment verification and field position adjustment on target coverage and normal tissue sparing. METHODS AND MATERIALS Port films were(More)
The Diatom EST database provides integrated access to expressed sequence tag (EST) data from two eukaryotic microalgae of the class Bacillariophyceae, Phaeodactylum tricornutum and Thalassiosira pseudonana. The database currently contains sequences of close to 30,000 ESTs organized into PtDB, the P.tricornutum EST database, and TpDB, the T.pseudonana EST(More)
The influence of phospholipids on the ultrastructure and metabolism of reconstituted surfactants has not been well defined. The aim of this study was to determine if changes in the phospholipid composition of reconstituted surfactants altered their biophysical properties, ultrastructure, and conversion to light subtype by cycling. We prepared various(More)
Alveolar surfactant is known to exist in several morphologic forms or subtypes which have been separated from bronchoalveolar lavage fluid (BAL) by two types of methods-differential centrifugation (DC) and equilibrium buoyant density gradient centrifugation (EBDC). DC separates BAL into large aggregates (LA) and small aggregates (SA); EBDC separates BAL(More)
The extracellular conversion of lung surfactant from tubular myelin to the small vesicular form has previously been shown to require a serine-active enzyme called "surfactant convertase." In the present study, a 72kD serine-active enzyme previously identified in mouse lung alveolar lavage and having convertase activity was partially sequenced. Sixty-eight(More)
We recently reported the purification and partial amino acid sequence of "surfactant convertase," a 72-kDa glycoprotein involved in the extracellular metabolism of lung surfactant (S. Krishnasamy, N. J. Gross, A. L. Teng, R. M. Schultz, and R. Dhand. Biochem. Biophys. Res. Commun. 235: 180-184, 1997). We report here the isolation of a cDNA clone encoding(More)
Convertase has homology with carboxylesterases, but its substrate(s) is not known. Accordingly, we determined whether dipalmitoylphosphatidylcholine (DPPC), the major phospholipid in surfactant, was a substrate for convertase. We measured [(3)H]choline release during cycling of the heavy subtype containing [(3)H]choline-labeled DPPC with convertase,(More)
OBJECTIVE This study used quantitative radiological imaging to determine the effect of surgical resection on postoperative survival of patients with malignant astrocytomas. Previous studies relied on the surgeons' impressions of the amount of tumor removed, which is a less reliable measure of the extent of resection. METHODS Information concerning(More)
PURPOSE To report the acute effects of laser in situ keratomileusis (LASIK) on the corneal endothelium. METHODS Twenty eyes of 10 consecutive patients (mean age, 38.1 +/- 10.84 years) underwent bilateral simultaneous LASIK for myopic astigmatism (spherical equivalent ranging from -1.75 to -7.13 diopters) without any complications. Each eye was evaluated(More)
Surfactant convertase is required for conversion of heavy density (H) natural surfactant to light density (L) subtype during cycling in vitro, a technique that reproduces surfactant metabolism. To study mechanisms of H to L conversion, we prepared liposomes of dipalmitoylphosphatidylcholine (DPPC) and phosphatidylglycerol (PG), or the phospholipids (PL) in(More)