Heavy metal concentrations in blood cells in patients with amyotrophic lateral sclerosis.

Manganese (Mn) and selenium (Se) concentrations in blood cells were measured by neutron activation analysis. Blood was obtained from patients with amyotrophic lateral sclerosis (ALS), patients with other neurological diseases and control subjects. Dried blood cells were activated by neutron irradiation. Mn was determined after chemical separation and Se was determined nondestructively. Mn concentrations in blood cells from ALS patients were significantly lower (P less than 0.01) than those from the other groups. The Mn concentrations were also significantly lower (P less than 0.01) in late than in earlier stages of ALS. Se concentrations in blood cells from ALS patients were significantly higher (P less than 0.01) than those from the other two groups. A generalized abnormal distribution of these metals may play a role in the pathogenesis of this disorder. Bromine, zinc, rubidium, and iron concentrations of erythrocytes were the same in all groups.

The distribution of ascorbic acid between various cellular components of blood, in normal individuals, and its relation to the plasma concentration.

1. A study was undertaken to investigate the distribution of ascorbic acid between various cellular components of blood, in normal individuals, and its relation to the plasma concentration. Forty-one unsupplemented individuals and sixteen supplemented (2 g/d for 5 d) individuals were studied. 2. Granulocytes, mononuclear leucocytes, platelets and erythrocytes were separated by differential sedimentation and centrifugation. Ascorbic acid contents were measured by the dinitrophenylhydrazine method. 3. Ascorbic acid content per cell was higher in mononuclear leucocytes and granulocytes than in platelets and erythrocytes. Intracellular ascorbic acid concentrations, calculated from published values for cell volumes, when compared with the plasma concentration showed a marked ability to concentrate ascorbic acid in mononuclear leucocytes (80 times), platelets (40 times) and granulocytes (25 times). 4. Erythrocytes showed little ability to concentrate ascorbic acid over the normal range of plasma concentration but because of their relative numbers they and the plasma fraction accounted for most of the blood-borne ascorbic acid (greater than 70%). 5. The ascorbic acid content of granulocytes, platelets and erythrocytes showed a significant positive correlation with the plasma concentration and supplementation with ascorbic acid significantly increased the content of these cell types. Mononuclear leucocytes in contrast did not show any such relationship. 6. The ability of the mononuclear leucocytes to maintain the highest levels of ascorbic acid in the cell types studied, despite variation in plasma availability, warrants further study, particularly in view of the importance of these cells in immunocompetence.

Simultaneous determination of iron, zinc, selenium, rubidium, and cesium in serum and packed blood cells by neutron activation analysis.

We determined the iron, zinc, selenium, rubidium, and cesium concentrations in serum and packed blood cells by instrumental neutron activation analysis without chemical separations. Lyophilized samples were irradiated for 12 days at a flux of 10(13) neutrons-cm-2-s-1, mineralized by wet digestion, and measured two times with a high-resolution Ge(Li) detector--for 6 h about a month after the irradiation and for 15 h two or three months after the irradiation, The following values were obtained: 163 +/- 0.43 mg/liter (serum iron), 1025 +/- 136 mg/kg wet wt (packed cells iron), 1¿ +/- 0.20 mg/liter (serum zinc), 11.15 +/- 1.83 mg/kg wet wt (packed cells zinc), 0.13 +/- 0.02 mg/liter (serum selenium), 0.16 +/- 0.03 mg/kg wet wt (packed cells selenium), 0.17 +/- 0.04 mg/liter (serum rubidium), 4.28 +/- 0.98 mg/kg wet wt (packed cells rubidium), 0.74 +/- 0.20 microgram/liter (serum cesium), and 4.82 +/- 2.10 microgram/kg wet wt (packed cells cesium).