Clonal differences in copper and zinc tolerance of birch in metal-supplemented soils.

Metal tolerance of a range of birch clones (Betula pendula and Betula pubescens) originating from metal-contaminated sites in England, Wales, Belgium and Finland were tested in soils supplemented with several concentrations of copper (Cu) or zinc (Zn) (500, 2000, 5000 mg kg-1 dry wt. soil of CuSO(4).5H2O or ZnSO(4).7H2O) for 4 months and with sub-toxic metal supplements (500 mg CuSO4, 2000 mg ZnSO4) for 6 months. When grown at high concentrations of metals, severe toxicity symptoms (growth inhibition, chlorosis, necrosis) and clear evidence for differences in tolerance to this toxicity were found in a subset of the clones. When all clones were grown at a much lower, sub-toxic level of metal, again significant differences could be found between some of the clones. Clones derived from the same population varied greatly in their tolerance. However, the overall pattern of metal specificity varied in agreement with the type of soil contamination at the site of origin. The growth of the clones from Harjavalta Cu/nickel smelter area was 19% better in Cu than in Zn-supplemented soil, on average. The growth of clones from Maatheide Zn smelter are was 19% poorer in Cu- than in Zn-supplemented soil. Sensitive clones accumulated more Cu and Zn to the above-ground parts. Some birch clones were able to survive at about 20-fold higher than typical total background Cu or Zn concentrations, whereas most clones were able to grow without serious toxic symptoms at about 10-fold concentrations.

The nutritional status of Finnish home-living elderly people and the relationship between energy intake and chronic diseases.

The nutritional status and the impact of non-progressive chronic diseases on energy intake were determined in 90 home-living people aged from 73 to 94 years. The nutritional status was assessed by dietary, anthropometric, biochemical and haematological methods. Energy intake (6.0, SD 1.7 MJ) in women was low compared with the Nordic Nutrient Recommendation but in men it (8.0, SD 2.1 MJ) was in keeping with this recommendation. Despite the low energy intake the mean BMI value of women was moderately high (27, SD 5.3 kg/m2). In men the mean was 26, SD 4.0 kg/m2. The intakes of vitamins and minerals met the recommendation, except for those of folic acid and zinc. The blood levels of both these two nutrients were within reference limits. Men suffering from chronic diseases received less (p < 0.015) energy (7.5, SD 1.76 MJ) than other men (8.9, SD 2.0 MJ). This relationship was not found in women. In conclusion, the nutritional status of people aged over 70 years old living at home was good. The presence of chronic diseases affected the energy intake in men but not in women.

Effect of drinking water fluoridation on hearing of patients with otosclerosis in a low fluoride area: a follow-up study.

Fluorine content in bone samples taken from the middle ears of otosclerotic patients was determined. Otosclerotic stapes footplate was found to have a significantly higher content of fluorine than skeletal bone from the meatus. Fluorine contents in footplate and meatal wall samples of otosclerotic patients drinking fluoridated water were slightly higher than those of patients drinking low-fluoride water. In the clinical part of the study, hearing levels of 280 patients with otosclerosis living in an area with low-fluoride water were assessed. In 344 operated ears, the preoperative and long-term postoperative air conduction and bone conduction thresholds of patients drinking fluoridated water did not differ significantly from those of patients drinking low-fluoride water. After a mean follow-up period of 9.6 years, air conduction thresholds of non-operated ears in patients drinking fluoride-poor water were found to be significantly worse than those of patients drinking fluoridated tap water, likewise there were significant differences in bone conduction thresholds at 2 and 4 kHz. Thus, fluoridation of drinking water has a beneficial effect on non-operated otosclerotic ears but has no significant effect on hearing levels of operated ears.

Serum copper and the risk of acute myocardial infarction: a prospective population study in men in eastern Finland.

The authors investigated the association of serum copper concentration with the risk of acute myocardial infarction in 1,666 randomly selected men aged 42, 48, 54, or 60 years who had no symptomatic ischemic heart disease at entry. Baseline examinations in the Kuopio Ischaemic Heart Disease Risk Factor Study in Eastern Finland were done during 1984 to 1988. In Cox multivariate survival models adjusting for age, examination year, ischemic electrocardiogram in exercise, maximal oxygen uptake, diabetes, family history of ischemic heart disease, cigarette-years, mean systolic blood pressure, serum high density lipoprotein (HDL) cholesterol subfraction HDL2 and low density lipoprotein (LDL) cholesterol concentrations and blood leukocyte count, serum copper concentration in the two highest tertiles (1.02-1.16 mg/liter and 1.17 mg/liter or more) associated with 3.5-fold (95% confidence interval (Cl) 1.3-9.4, p less than 0.05) and 4.0-fold (95 percent Cl 1.5-10.8, p less than 0.01) risk of acute myocardial infarction. These data indicate that high copper status, reflected by elevated serum copper concentration, is an independent risk factor for ischemic heart disease.

Interactions of serum copper, selenium, and low density lipoprotein cholesterol in atherogenesis.

OBJECTIVE: To investigate the interactions between serum copper, selenium, and low density lipoprotein cholesterol concentrations with regard to the progression of carotid atherosclerosis. DESIGN: Longitudinal study of a cohort of middle aged men followed up for 24 months. SETTING: Epidemiological survey of the population of seven communities in eastern Finland. SUBJECTS: 126 men aged 42, 48, 54, or 60 at examination randomly selected from a population based sample of 2682 men. MAIN OUTCOME MEASURES: Increase in maximal carotid intima media thickness. RESULTS: The mean increase in the maximal common carotid intima media thickness after two years was greater in men with high serum copper concentrations (0.16 mm compared with 0.08 mm in men with concentrations less than 17.6 mumol/l; p = 0.010), those with low serum selenium concentrations (0.15 mm compared with 0.09 mm in men with concentrations greater than or equal to 1.40 mumol/l; p = 0.035), and those with raised serum low density lipoprotein cholesterol concentrations (0.15 mm compared with 0.08 mm in men with concentrations less than 4.0 mmol/l; p = 0.032) after adjustment for age and cigarette pack years in a three way analysis of covariance. A raised serum low density lipoprotein concentration was associated with accelerated progression of atherosclerosis only in men with higher than median serum copper concentrations (net difference 0.22 mm; p less than 0.001 for two way interaction), and this synergism was even more pronounced in men with serum selenium concentrations below the median value (net difference 0.41 mm; p = 0.042 for three way interaction). CONCLUSION: These data provide evidence of a synergistic effect of copper (a pro-oxidant), a low serum concentration of selenium (a cofactor of an enzyme that scavenges free radicals), and low density lipoprotein cholesterol concentration in atherogenesis.