ShdA is a large outer membrane protein of the autotransporter family whose passenger domain binds the extracellular matrix proteins fibronectin and collagen I, possibly by mimicking the host ligand heparin. The ShdA passenger domain consists of ϳ1,500 amino acid residues that can be divided into two regions based on features of the primary amino acid sequence: an N-terminal nonrepeat region followed by a repeat region composed of two types of imperfect direct amino acid repeats, called type A and type B. The repeat region bound bovine fibronectin with an affinity similar to that for the complete ShdA passenger domain, while the nonrepeat region exhibited comparatively low fibronectin-binding activity. A number of fusion proteins containing truncated fragments of the repeat region did not bind bovine fibronectin. However, binding of the passenger domain to fibronectin was inhibited in the presence of immune serum raised to one truncated fragment of the repeat region that contained repeats A2, B8, A3, and B9. Furthermore, a monoclonal antibody that specifically recognized an epitope in a recombinant protein containing the A3 repeat inhibited binding of ShdA to fibronectin.

Preeclampsia is a disorder resulting in significant fetomaternal complications with no definitive pharmacological intervention. A bufadienolide, marinobufagenin, has been implicated in the etiology of preeclampsia. We investigated both the blood and urine levels of marinobufagenin in preeclamptic and control subjects. Preeclamptic and normotensive pregnant women were recruited at various gestational age periods. Blood and urine specimens were obtained and analyzed for marinobufagenin levels and creatinine. The former determination was performed utilizing a new, novel chemifluorescent enzyme-linked immunosorbent assay. The marinobufagenin levels were higher in preeclamptics than in the controls in both serum and urine at various gestational age periods. Additionally, the mean level of marinobufagenin in the preeclamptic group was significantly greater than in controls in both blood and urine specimens ( P < 0.05). These data are consistent with a role for marinobufagenin in the etiology of preeclampsia. This study demonstrated comparable results in blood and urine samples. This suggests that subsequent studies on levels of marinobufagenin as a screening test for preeclampsia could be done utilizing urine samples, which are easier to obtain, less invasive, more cost-effective, and as accurate as the serological tests.

There is increasing interest in the role of wetland plants in the aquatic phytoremediation of toxic metals. In this experiment, we evaluate the Cr removal capacity of four hydrophyte species (Nasturtium officinale L., Veronica beccabunga L., Mentha longifolia L., R.Br., Cardamine uliginosa L.) under varying nutritional conditions (full-strength and half-strength solution cultures), and over a range of Cr concentration (0, 2, 4, 6, and 8 mg L -1 ). The results indicate that Cr accumulation is affected by both initial Cr concentration and strength of the nutrient solution. Phytoaccumulation increased with initial Cr concentration and plants grown in the full-strength solution accumulated more Cr at the higher initial solution concentration. Cr was predominantly accumulated in the roots, with minimal shoot translocation, which limits the hazard of Cr entering the food chain through ingestion by animals. Accumulation was large and reached up to 6700 mg Cr Kg -1 in the roots of Veronica beccabunga.

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