Investigations determined that the cell matrix-associated prekallikrein (PK) activator is prolylcarboxypeptidase. PK activation on human umbilical vein endothelial cell (HUVEC) matrix is inhibited by antipain (IC(50)=50 microM) but not anti-factor XIIa antibody, 3 mM benzamidine, 5 mM iodoacetic acid or iodoacetamide, or 3 mM N-ethylmaleimide. Corn trypsin inhibitor (IC(50)=100 nM) or Fmoc-amin...

We use a multiscale approach to analyze adiabatic shear bands in a tungsten heavy alloy particulate composite deformed in plane strain tension at a nominal strain rate of 5000/s. Fifty IJ.m diameter circular tungsten particulates are assumed to be randomly distributed and perfectly bonded to the nickel-iron matrix. The volume fraction of particulates equals 50%. We first analyze transient coupl...

Effect of haying (hayed or not hayed prior to tillage), tillage (notillage, minimum tillage, or conventional tillage), and N fertilization (0 or 67 kg ha ') on surface infiltration rates, Q(h), was evaluated for Conservation Research Program (CRP) site conversion. Soils included Amor loam (fine-loamy, mixed, superactive, frigid Typic Haplustoll) and Cabba silt loam (loamy, mixed, superactive, c...

The purpose of this study is to develop a rat lumbosacral spinal cord injury (SCI) model that causes consistent motoneuronal loss and behavior deficits. Most SCI models focus on the thoracic or cervical spinal cord. Lumbosacral SCI accounts for about one third of human SCI but no standardized lumbosacral model is available for evaluating therapies. Twenty-six adult female Sprague-Dawley rats we...

When barley roots absorb Na(+) at concentrations ranging from 1 to 50 mm, in the presence of low concentrations of Ca(2+) and K(+), absorption of Na(+) is mediated by carrier mechanism 2 of alkali cation transport, mechanism 1 being unavailable for Na(+) transport under these conditions. The absorption isotherm depicting the rate of Na(+) absorption as a function of the external Na(+) concentra...

To study the effect of different concentrations of potassium in thenutrient solution and water stress on the quality and quantity yield of Lilium LA cv.Termoli, a pot experiment was conducted based on completely randomized design in sand and perlite medium (50:50) in three levels of potassium (Kfree, 6 mM K and and 12 mM K in Hoagland solution) with three replications. In the present study, the...

BACKGROUND Oxidative stress is considered to play a role in the pathogenesis of diabetic nephropathy. Angiotensin-converting enzyme (ACE) inhibitors are hypotensive drugs with a well-known effect in preventing the progression of chronic renal failure. Their mechanism of action is not clearly established. METHODS The effect of enalaprilat on hydrogen peroxide (H2O2) production by cultured muri...

PURPOSE The effects of dose distribution on dose-effect relationships have been evaluated and, from this, iso-effective doses (ED(50)) established. METHODS AND MATERIALS Wistar rats were irradiated on the cervical spinal cord with single doses of unmodulated protons (150 MeV) to obtain sharp lateral penumbras, using the shoot-through technique, which employs the plateau of the depth-dose prof...

Human aromatase is responsible for the last step of estrogen biosynthesis, for the aromatization of ring A of androstenedione (ASD) or testosterone. In this work the mechanism of aromatization was studied using gas phase and hybrid QM/MM calculations. It is shown that human aromatase can efficiently catalyze the aromatization process via a Compound I (or Compound II) mediated pathway. The natur...