Urine but not plasma nitric oxide metabolites are decreased in women with preeclampsia

OBJECTIVE: Nitric oxide is a potent vasorelaxant produced by endothelial cells. We tested the hypothesis that urinary and perhaps plasma nitric oxide metabolites would be reduced in women with preeclampsia. STUDY DESIGN: Plasma and urine from 14 women meeting strict clinical criteria for the diagnosis of preeclampsia and 20 normal nulliparous women were assayed for the stable metabolites of nitric oxide, nitrate and nitrite. RESULT: There was no significant difference of plasma concentrations of nitrate and nitrite between women with preeclampsia and women with normal pregnancies (32.7 +/- 3.1 vs 25.8 +/- 2.4 micromol/L). Plasma creatinine levels were elevated in women with preeclampsia (0.85 +/- 0.09 vs 0.66 +/- 0.02 mg/dl, p<0.01), indicating a reduced glomerular filtration rate. Urine concentrations of nitrate and nitrite normalized by creatinine excretion were significantly lower in women with preeclampsia compared with normal pregnant women (0.37 +/- 0.06 vs 0.69 +/- 0.11 micromol of nitrite per milligram creatinine, p. <0.05). CONCLUSIONS: Our study using concomitant measurement of plasma and urine nitrate and nitrite suggests a reduced production of nitric oxide in women with preeclampsia compared with normal pregnant women.     

Neutral Salt Effects on Stability of Whey Protein Isolate Foams

Addition of 0.1 M Na₂SO₄, NaCl, or NaSCN reduced maximum overruns of whey protein isolate (WPI) by 33%, 27%, and 38%. This was attributable to an ionic effect, i.e., the ions interacted with countercharges on the proteins thereby reducing electrostatic interactions. In contrast, at high concentrations (1M), Na₂SO₄ improved foam stability by 76% compared to WPI without salt. Chloride had an intermediate effect, whereas NaSCN did not improve foam stability. Increasing Na₂SO₄ concentration (2M) improved foam stability by 127% compared to control. The relative effectiveness of salts at improving foam stability and heat stability followed the Hofmeister series (SO₄^2-??).     

Plasma insulin levels in coronary artery disease

Seventy two consecutive patients without a history of diabetes and normal fasting plasma glucose were included in this study of insulin levels. Standard oral glucose tolerance test with 75 gm glucose and fasting and two hour insulin levels were estimated in all patients. Coronary artery disease (CAD) was confirmed or excluded by selective coronary arteriography. In 20 patients, CAD was diagnosed by electrocardiographic (ECG) and clinical evidence of earlier myocardial infarction. Mean fasting plasma insulin was 31.40 +/- 22.2 IU/dl in the CAD positive and 32.3 +/- 13.6 IU/dl in the CAD negative group. The mean two hour plasma insulin was 274.6 +/- 301.1 IU/dl in the CAD positive and 104.8 +/- 74.9 IU/dl in the CAD negative group (p < 0.04). Two hour plasma insulin levels were significantly higher in patients with atherosclerotic coronary artery disease. It is concluded that the estimation of a two hour plasma insulin level after 75 gm of glucose load, could help differentiate CAD from normals.     

Embeddings of Star Graphs into Optical Meshes without Bends

We show an embedding of the star graph into a rectangular optical multichannel mesh ofddimensions such that the embedding has no bends; that is, neighbors in the star graph always differ in exactly one coordinate in the mesh, to facilitate one-hop optical communication. To embed ann-star, the mesh can have any number of dimensionsdbetween 1 andn− 1. The embedding has load 1 and an expansion of at mostn^{d − 1}/d!. The size of the mesh will be at most We optimize the size of the host mesh using clique-partitioning to produce embeddings with expansions as low as unity. In two dimensions, for evenn, the mesh will be no larger thann×n(n− 2)!, and have an expansion of no more than 1 1/(n− 1). Further, we show how we can use a contraction method to efficiently embed the star graph into an optical mesh with near-unity aspect ratios. Contraction on a two-dimensional embedding will yield a mesh of size no larger thann×nfor evennwith a load of (n− 2)!.     

Estimation of Width and Depth of the Wetted Soil Volume Under a Surface Emitter,Considering Root Water-Uptake and Evaporation

A cylindrical flow model that describes local infiltration from a surface point source, by incorporating evaporation and water extraction by roots, was used to obtain numerical results that were the base for the development and testing of an empirical method for determining the surface and vertical components of the wetting front. The implementation of the mathematical model took place against two of the twelve USDA soil classes, using three water application rates for each one. The empirical methodology consisted of two simple, time dependent empirical relationships: a power law for the stage of the infiltration, which was applied in both directions and a polynomial for the stage after the end of the irrigation, applied only for the vertical component, to account for percolation losses. The statistical criteria used for the evaluation of the method showed good agreement between the numerical results and the values calculated by the empirical relationships. Based on the limited availability of necessary experimental data for detailed analysis of multidimensional transient infiltration, the introduction of such an empirical model, as a design tool for trickle irrigation systems, may contribute to the selection of the optimum application rate and lateral spacing.