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The aim of this study was to evaluate the usefulness of Phalaris arundinacea, Salix viminalis and Zea mays to the phytoremediation of the soil contaminated with nickel. A 2-year microplot experiment was carried out with plants growing on Ni-contaminated soil. Microplots (1 m2 × 1 m deep) were filled with Haplic Luvisols soil. Simulated soil contamination with Ni was introduced in the following doses: 0—no metals, Ni1—60, Ni2—100 and Ni3—240 mg kg−1. The phytoremediation potential of plants was evaluated using a tolerance index, bioaccumulation factor, and translocation factor. None of the tested plants was a species with high Ni phytoremediation potential. All of them demonstrated a total lack of usefulness for phytoextraction; however, they can be in some way useful for phytostabilization. Z. mays accumulated large amounts of Ni in the roots, which made it useful for phytostabilization, but, at the same time, showed little tolerance to this metal. For this reason, it can be successfully used only on soils medium-contaminated with Ni, where a large yield decrease did not occur. Its biomass may be safely used as cattle feed, as the Ni transfer from roots to shoots was strongly restricted. P. arundinacea and S. viminalis accumulated too little Ni in the roots to be considered as typical phytostabilization plants. However, they may be helpful for phytostabilization due to their high tolerance to Ni. These plants can grow in the soil contaminated with Ni, acting as a protection against soil erosion or the spread of contamination.

This study was designed to examine the effect of the rat atrial extract (RAE) and synthetic rat ANF123-150 (rANF) on the renal Na, K-ATPase activity in Wistar anesthetized rats. Na, K-ATPase activity was assayed by measuring the amount of inorganic phosphate liberated from ATP. RAE from 40.3, 80.6 mg of tissue and rANF in the following doses: 0.043, 0.087, 0.173, 0.260 nM/kg/min reduced Na, K-ATPase activity by 59, 64 and 11, 34, 37, 45% respectively in the renal medulla but not in the cortex. It was associated with the increase in diuresis and natriuresis. Five and ten minutes after the end of rANF administration, Na, K-ATPase activity was decreased by 78 and 57% respectively, diuresis and natriuresis were significantly higher than the control. After fifteen minutes enzyme activity returned to normal, diuresis and natriuresis were increased. After thirty minutes there was a 37% increase in Na, K-ATPase activity but diuresis and natriuresis were still higher than control values. We conclude that the inhibition of Na, K-ATPase in the medulla of the rat kidney is one of the mechanisms of ANF action.

Clinical presentation and course were studies in 45 consecutive patients (p)--39 males, 6 females with angiographically proven left main coronary artery stenosis (LMCA)50%. Mean age was 54.7 years. Three (6%) had no history of chest pain, 2 p (4%) had atypical chest pain, and the remaining (90%) had typical angina pectoris. 19 p (42%) had unstable angina, 20 p (44%) had suffered a myocardial infarction in the past. Outside an episode of chest pain most of the patients had an abnormal ECG with ST-T segment depression 2 mm or more in leads V3-6 and ST-T elevation in leads V1 and aVR. No significant differences were found when the abnormalities of the ST-T segment were compared to severity of LMCA obstruction. A symptom limited exercise test was performed in 17 (37%) p. It was abnormal in 13 p (29%). Thirty eight patients (85%) underwent bypass surgery and the mean number of bypass graft was 3.3. Seven patients were treated medically. In the surgical group four p (10.5%) died perioperatively. All of them had subtotal occlusion of LMCA, without significant lesions in the remaining coronary arteries, the ejection fraction (EF) was above 66%. Among thirty four living patients thirty have been asymptomatic. In the medically treated group 3 p (42%) died and only two of four survivors were asymptomatic at a mean follow-up 35.7 months. Left ventricle of all died patients were severely damaged (EF mean 28%), right coronary artery (RCA) was totally occluded and all had rythm disturbances. We conclude, that patients with significant LMCA stenosis had a good prognosis when treated surgically.(ABSTRACT TRUNCATED AT 250 WORDS)