Search PubMed⌕ Search

Biomedical subjects

C R Angle

Publications and source records attributed to C R Angle.

At least 55 records · Page 3Linked to original sources
PubMed1980

Erythrocyte nucleotides from control and lead-treated rabbits.

Significant abnormal elevations of the erythrocyte pyrimidine nucleotides UTP and CTP were observed in rabbits after 60 days of oral exposure to lead acetate at a dose of 30 mg/kg/day. No significant changes in purine nucleotides were observed. The increased erythrocyte pyrimidine nucleotides were accompanied by a decrease in red cell pyrimidine 5'-nucleotidase (P5N) activity, an increase in zinc erythrocyte protoporphyrin concentration, and elevated whole blood lead levels. Quantitative measurement of the major 5'-nucleotides in rabbit red cells was achieved by high performance liquid chromatography. The accumulation of UTP and CTP as the results of chronic lead exposure may be explained on the basis of inhibited P5N coupled with the presence of an active nucleoside diphosphokinase.

5'-Nucleotidase↗
PubMed1979

Environmental lead and children: the Omaha study.

Blood lead (Pb B) was determined in 1232 samples from 831 children in Omaha and correlated with air lead (Pb A) concentrations of 0.02-1.69 microgram/m3 from 1971 to 1977. A bivariate equation for ages 6-18 yr based on these data predicts an increase in Pb B of 1.4 microgram/dl as Pb A increases from 1 to 2 microgram/m3. Pb B increases 7 microgram/dl as the mean values for soil and house dust Pb increase from 100 to 750 microgram/g. Multiple regression analysis shows that the combined effects of air, soil, and house dust Pb account for 21% of the variance of Pb B, with a high intercorrelation of all 3 variables. Since the variance of repeat sampling in individuals accounted for 38% of the total variance of Pb B, approximately 40% is unexplained and requires measurement of Pb from dietary and other sources.

Adolescent↗
PubMed1978

Low level lead and inhibition of erythrocyte pyrimidine nucleotidase.

Pyrimidine 5'-nucleotidase (P5N, EC 3.1.3.5) appears to be a sensitive index of exposure to low level lead. In 21 children 2 to 5 years old with blood leads of 7 to 80 micrograms/dl there was a negative linear correlation of blood lead and red cell P5N: r = -0.60 (P less than 0.01), Y = -0.11X + 12.3. In rats, the enzyme assay was quantitatively similar to that of the human. A treatment group of 12 rats received lead acetate, 36 mg/kg/day, of lead as 0.17 M lead acetate for 24 days. The blood lead of treated rats increased from the control value of 8.3 +/- 1.3 to 36.0 +/- 0.5 on day 24; P5N decreased from 18.3 +/- 0.8 units to 9.0 +/- 1.0 and was below control values at a blood lead of 25. There was a significant negative linear correlation of blood lead and P5N: r = -0.85; n = 17; P less than 0.001; Y = 0.34X + 20.9 that was independent of the correlationship with the reticulocytes. At these levels of blood lead and P5N there was no significant change in the hexokinase, hemoglobin or red cell count and no evidence of stippling.

5'-Nucleotidase↗
PubMed1977

Effect of anemia on blood and tissue lead in rats.

The effect of anemia on the lead content of blood, red cells, and tissue was studied in rats given oral lead, 54 mg/kg-day for 6 days. The 16 rats made anemic (hematocrit, 26%) by bleeding on days 1, 3, and 5 had significantly higher concentrations of lead in the kidney, liver, red cells, blood, and brain (but not in the bone marrow). Increases in blood lead in anemic subjects were correlated with the concentrations in red cells, kidney, and liver. The greater increase in the lead content of all tissues of the anemic rats is consistent with increased lead absorption in anemia and is considered relevant to the clinical coexistence of anemia and lead poisoning.

Anemia↗
PubMed1976

How effective is safety packaging?

Of 96 ingestions involving safety packaging, 82% involved misuse. The package in some way was unacceptable to the consumer--it was too difficult to open or too difficult to close. Nonacceptance by the elderly was not a significant factor. In only 18% of the safety packaged ingestions, did the child upen the package. The child was more likely to be able to open the screw-cap and the strip-pack. The pop-off and press-lift were not opened by any child but were types misused only by parents. The older child with a record of prior poisoning was most likely to open a safety package. These children would appear to represent a hard core of risk subjects refractory even to safety packaging. Safety packaging has had a dramatic effect on the morbidity and mortality of accidental poisoning. There are two remaining problems that require further study: 1. The analysis of technical factors impeding consumer acceptance and child proofing. The ideal package is so easily handled by the adult that misuse does not occur, but is too difficult for the child to open. 2. The personality characteristics of the safety-package-resistant child. Safety packaging, as implemented by the Comsumer Product Safety Commission, has had remarkable success. Education did not reduce accidental poisoning; safety packaging does. Pediatricians, pharmacists, and toxicologists must work with industry and the Consumer Product Safety Commission to complete the goal of elimination of accidental poisoning.

Aspirin↗