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C C Scott

Publications and source records attributed to C C Scott.

18 recordsLinked to original sources
PubMed1983

The effect of left atrial histology and dimension on P wave morphology.

This study correlates left atrial appendage cell size, atrial fibrosis and echocardiographic (echo) measurement of left atrial size with P wave morphology. Twelve patients with known mitral valve disease had echo measurements of left atrial size with P wave morphology. Twelve patients with known mitral valve disease had echo measurements of left atrial size prior to mitral valve surgery; patients had varying degrees of left atrial enlargement. The left atrial appendage, removed at the time of surgery, was stereologically assessed for percent fibrosis and the diameters of 50 cells were measured and averaged. These factors were correlated with P wave amplitude and duration in lead II, greatest length in any led, PR segment (end of P wave to onset of QRS), P to PR segment ratio (in lead II) and the PR interval. There was a good correlation of left atrial cell diameter with P wave amplitude (r = .69, p = 0.01). There was a good inverse correlation of percent fibrosis with the PR segment (r = -.72, p = 0.01) and a direct correlation of fibrosis with the ratio of P wave length to PR segment (r = .67 p = 0.01). There was a trend for percent fibrosis to correlate with PO wave duration but not height. No correlation was noted for any of the P wave characteristics and left atrial size. This study demonstrates that there is a correlation of P wave height with cell diameter and P wave length and PR segment with fibrosis. These data are helpful in understanding the electrocardiographic P wave.

Cardiomegaly↗
PubMed1979

Regulation of ether lipids and their precursors in relation to glycolysis in cultured neoplastic cells.

Tumors typically show high rates of glycolysis and elevated levels of ether lipids, particularly the alkyldiacylglycerols; thus, we investigated the relationship between ether lipid accumulation and glucose metabolism in a neoplastic cell line (B2-1). The B2-1 cells grown in 5.5 mM galactose in the absence of glucose produced very low levels of alkyldiacylglycerols, triacylglycerols, lactic acid, and dihydroxyacetone-P. Increasing concentrations of glucose caused a progressive increase in lactic acid, dihydroxyacetone-P, and up to a ten-fold increase in alkyldiacylglycerols and triacylglycerols. Glucose supplements also caused an increased incorporation of [9,10-3H]palmitic acid into alkyldiacylglycerols and triacylglycerols. These metabolic changes appeared to be independent of altered growth rates of the cells. The addition of hexadecanol along with glucose to the cultures resulted in a shorter lag and a more rapid rate of accumulation of alkyldiacylglycerols; hexadecanol supplements alone had no effect. The extent of uptake and oxidation of hexadecanol was similar in both the glucose and galactose-grown cells. These results indicate that the levels of alkyldiacylglycerols in neoplastic cells can be regulated by the extent their precursors are formed from glucose.

Animals↗
PubMed1976

A comparative analysis of the ultrastructure of hydrocarbon-oxidizing micro-organisms.

The ultrastructure of a variety of micro-organisms was compared after growth on hydrocarbon and non-hydrocarbon substrates. Hydrocarbon-grown organisms were characterized by the presence of intracellular electron-transparent inclusions which in many cases appeared membrane-bound. With one exception, non-hydrocarbon-grown organisms did not contain electron-transparent inclusions. Insignificant amounts of poly-beta-hydroxybutyric acid were produced by the hydrocarbon-grown micro-organisms. After growth on hydrocarbons, all the microorganisms had accumulated varying amounts of the respective unmodified hydrocarbon growth substrate.

Acinetobacter↗
PubMed1976

Isolation and characterization of membranes from a hydrocarbon-oxidizing Acinetobacter sp.

Membranes were isolated and purified from nutrient broth-yeast extract- and hexadecane-grown cells of Acinetobacter sp. strain HO1-N. Two membrane fractions were isolated from nutrient broth-yeast extract-grown cells, the cytoplasmic membrane and the outer membrane. In addition to these two membrane fractions, a unique membrane fraction was isolated from hexadecane-grown cells (band 1) and characterized as a lipid-rich, low-density membrane containing high concentrations of hexadecane. The outer membrane preparations of Acinetobacter, obtained from nutrient broth-yeast extract- and hexadecane-grown cells, exhibited a low ratio of lipid phosphorus to protein and contained phospholipase activity and 2-keto-3-deoxyoctulosonic acid. Phosphatidic acid cytidyltransferase, adenosine triphosphatase, and reduced nicotinamide adenine dinucleotide oxidase were recovered almost exclusively in the cytoplasmic membrane fractions. The cytoplasmic membrane fractions contained 20 to 25 polypeptide species on sodium dodecyl sulfate-polyacrylamide gels, and the outer membrane fractions contained 15 to 20 polypeptide species. A major polypeptide species with an apparent molecular weight of approximately 42,000 to 44,000 was found for all outer membrane fractions. The buoyant densities of the cytoplasmic membrane fractions and the outer membrane fractions were closely similar, necessitating their separation by differential centrifugation. Band 1 of hexadecane-grown cells had a ratio of lipid phosphorus to protein that was almost twice that of cytoplasmic membrane and a correspondingly low buoyant density (1.086 g/cm3). Enzyme activities associated with band 1 were identical to those associated with the cytoplasmic membrane. The electrophoretic banding pattern of band 1 was essentially identical to the banding pattern of the cytoplasmic membrane. The phospholipid and neutral lipid compositions of the isolated membrane fractions were determined as qualitatively similar, with significant quantitative differences. The ultrastructure characteristics of the respective membrane fractions were examined by the negative-stain technique.

Acinetobacter↗
PubMed1976

Characterization of intracytoplasmic hydrocarbon inclusions from the hydrocarbon-oxidizing Acinetobacter species HO1-N.

The ultrastructure of Acinetobacter sp. strain HO1-N grown on hydrocarbon and nonhydrocarbon substrates was compared using thin sections and freeze-etching. Hydrocarbon-grown cells were characterized by the presence of intracytoplasmic membrane-bound hexadecane inclusions. This membrane did not exhibit a typical unit membrane structure but appeared as a monolayer. The freeze-etch technique revealed the internal structure of the hexadecane inclusions and provided evidence for the presence of a smooth-surfaced limiting membrane. Freeze-etching also revealed intracytoplasmic membranes in the hexadecane-grown cells. These ultrastructural modifications were not present in nonhydrocarbon-grown cells. The hexadecane inclusions were isolated from Acinetobacter. Negative-staining of the inclusions revealed electron-transparent vesicles approximating the size of the inclusions seen in whole cells. Freeze-etching of the purified inclusions revealed membrane-bound vesicles. The purified inclusions exhibited a relatively high value of lipid phosphorus to protein. The lipid composition and the electrophoretic banding pattern of the inclusions on sodium dodecyl sulfate-polyacrylamide gels were determined and compared with other membrane fractions (outer membrane and cytoplasmic membrane) previously isolated from this organism.

Acinetobacter↗
PubMed1969

Hospital air.

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Air Microbiology↗