Biochim Biophys Acta
December 1995
Biochemical changes in the pulmonary surfactant system caused by exposure to toxicants are often accompanied by an influx of inflammatory cells into the lungs. We have investigated the possibility that the inflammatory and surfactant biochemical effects might be connected. Co-treatment with dexamethasone, a synthetic anti-inflammatory glucocorticoid, mitigated the increases in free cells and total intracellular surfactant phospholipid normally seen in animals given silica alone, suggesting a relationship between the free cell population of the alveoli and the surfactant system during alveolitis.
View Article and Find Full Text PDFThe more differentiated components of a primary tumor may produce substances that reduce the growth rate and metastatic potential of more aggressive components. In the Dunning R-3327 prostatic adenocarcinoma model, cancer cell motility is required for metastatic potential. Medium conditioned by the non-motile, non-metastatic G subline contains proteins of molecular weight 50-100 kDa that inhibited the motility of the highly motile, highly metastatic MAT-LyLu subline.
View Article and Find Full Text PDFBackground: It is well established that alterations in the expression of cell surface glycoproteins occur during the course of tumorigenesis and can be detected immunohistochemically. However, no consistent markers of malignancy in mouse hepatocellular tumors have yet been identified.
Experimental Design: Lectin histochemistry, using three bile duct-specific lectins, Dolichos biflorus agglutinin (DBA), peanut agglutinin (PNA) and soybean agglutinin (SBA), and anti-epidermal keratin immunohistochemistry, was conducted on formalin-fixed, paraffin-embedded tissues of a spectrum of benign and malignant hepatocellular proliferative lesions of mice, including hepatocholangiocarcinomas.
Background: Localization of surfactant protein A (SP-A) to nucleus of type II cells isolated from the lungs of rats has been reported. Data suggested that most SP-A was located within lamellar bodies of the type II cell; however, some SP-A was found in other cytoplasmic regions of the cell and in particular in the nucleus.
Experimental Design: Type II cells and type II cell nuclei isolated from the lungs of rats were reacted with affinity-purified antibodies against SP-A.
The expression of phenotypic markers was examined during fetal and neonatal differentiation of rat tracheal epithelial (RTE) cells. The rat counterpart of human keratin 18 was predominantly found in columnar cells in the adult trachea. It was detected in the primordial tracheal epithelium first seen on gestational day (GD) 12 (term = 21.
View Article and Find Full Text PDFWe have determined the distribution of surfactant protein A (SP-A) in isolated type II cells from the lungs of rats by using immunofluorescence in conjunction with a laser scanning microscope fitted with a confocal aperture. Because of the very narrow depth of field of this microscope (less than 0.4 microns) in the confocal format, we were able to optically section type II cells and determine both the distribution of SP-A in the type II cell and the distribution of the lamellar bodies.
View Article and Find Full Text PDFJ Electron Microsc Tech
May 1991
Confocal scanning laser microscopy (CSLM) represents an exciting new tool for scientific disciplines which focus on mechanistic studies such as experimental pathology. Enhanced resolution in the specimen plane and rejection of out-of-focus fluorescence flare allow analysis of specific nucleic acid sequences, enzymes, structural macromolecules, and cellular homeostasis utilizing fluorescent probes. Four different experimental applications are discussed which utilize CSLM to evaluate pathological processes at the subcellular, cellular, and tissue levels.
View Article and Find Full Text PDFAm J Respir Cell Mol Biol
September 1990
The synthesis of the major surfactant protein, SP-A, was studied in activated alveolar type II cells isolated from the lungs of rats exposed to silica by intratracheal instillation. Exposure of rats to silica resulted in large increases in the levels of disaturated phosphatidylcholine and SP-A in the extracellular and intracellular surfactant compartments. Isolated type II cells were used to determine if the observed increases in SP-A were associated with increased SP-A synthesis.
View Article and Find Full Text PDFThe authors investigated the power of the New Medical College Admission Test (MCAT) to predict performance of first-year medical students at the University of North Carolina. The approach was to compute the additional variance in performance explainable by the New MCAT after the effects of other routinely available admissions variables were taken into account. This incremental validity of the New MCAT was found to be substantial, with performance prediction improved by 23 to 38 percent, and was higher in this range when nationally standardized performance measures were employed as the outcome variable.
View Article and Find Full Text PDFTwo patients with "Gaisböck syndrome" (stress polycythemia) were found to have been under chronic "stress" with REM sleep decrease, decreased nocturnal ADH-like activity and consequent nocturnal water loss. The role of REM decrease with chronic "stress" in causing secondary decrease in nocturnal ADH-like activity was emphasized as the means by which "stress" caused the blood volume changes seen with these two patients. Some factors that possibly could play a role in the pathophysiology of this syndrome were ruled out and other factors not studied here were considered for future investigation.
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