Publications by authors named "D Lipke"

A hyperbaric aerodynamic levitator has been developed for containerless materials research at specimen temperatures exceeding 2000 °C and pressures up to 10.3 MPa (1500 psi). This report describes the prototype instrument design and observations of the influence of specimen size, density, pressure, and flow rate on levitation behavior.

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Alterations in polyamine metabolism may be a critical mechanism of monocrotaline (MCT)-induced structural remodeling of the pulmonary vasculature. In the present study, the hypothesis that MCT, through the induction of oxidative stress, modulates cellular polyamine regulatory mechanisms which in turn might be involved in the upregulation of fibronectin production in pulmonary artery endothelial cells (PAEC) was examined. A 24-h treatment with MCT significantly increased PAEC polyamine concentrations as compared to vehicle-treated cells.

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The objective of this study was to evaluate prospectively the influence of gestational age (GA) and short-term antenatal steroids on total lymphocyte count and lymphocyte subsets in cord blood from preterm infants. Two-color flow cytometric analyses of lymphocyte subsets were performed on cord blood collected from 67 infants. These infants were grouped according to GA: group I (term, n = 19); group II (GA 33-37 weeks, n = 25); group III (GA <33 weeks, n = 23).

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The use of a combination of monofluorescein adducts of spermidine (FL-SPD) and spermine (FL-SPM) with confocal laser scanning microscopy (CLSM) provides a useful means for monitoring the fate and time-dependent changes in the distribution of transported polyamines within living cells. Polyamine-fluorescein adducts were synthesized from fluorescein isothiocyanate and the appropriate polyamine. Monofluorescein polyamine adducts (ratio 1:1) were isolated using thin layer chromatography, and the structure and molecular weight of the monofluorescein polyamine adducts were confirmed using NMR and mass spectroscopy, respectively.

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Alterations in lung angiotensin converting enzyme (ACE) activity in monocrotaline (MCT)-induced pulmonary hypertension in rats have suggested a pathophysiologic role for angiotensin II (AII) in pulmonary vascular remodeling. ACE inhibitors suppress MCT-induced pulmonary hypertension; however, losartan, an angiotensin type 1 (AT1) receptor antagonist, was without impact. The present study examined AII receptor binding characteristics by radioligand binding during the development of MCT-induced pulmonary hypertension.

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