Population norms for serum ferritin.

The purpose of this study was to establish norms for the serum ferritin determination. Analyses of blood samples submitted for a panel of 29 laboratory tests in 964,325 individuals of a random population of all races in 10 centers in the United States were used. A subgroup of 59,914 ferritin values was constituted from panels that showed the values of the 28 other laboratory tests inside prescribed limits that approached the conventionally used reference ranges.

Population-based study of glycosylated hemoglobin, lipids, and lipoproteins in nondiabetic adults.

Glycosylated hemoglobin levels reflect glucose homeostasis over the preceding months. Many investigators have reported levels of glycosylated hemoglobin in diabetics and have noted a strong correlation of these levels with lipids and lipoproteins, but not with HDL cholesterol. We report here the first population-based study of the predominant fraction of glycosylated hemoglobin, HbA1, and its correlates in nondiabetics.

Screening for carbohydrate intolerance in pregnancy: a comparison of two tests and reassessment of a common approach.

The usefulness of glycosylated hemoglobin as a prenatal screening test for carbohydrate intolerance was studied in 806 consecutive subjects by correlating glycosylated hemoglobin to 1-hour post-50 gm Glucola plasma glucose levels, 3-hour oral glucose tolerance tests, and perinatal and maternal outcomes. Sixty-seven subjects whose 1-hour post-50 gm Glucola plasma glucose levels were greater than or equal to 150 mg/100 ml underwent 3-hour oral glucose tolerance tests; 12 were diagnostic of carbohydrate intolerance. Compared to carbohydrate-tolerant control subjects, gravid patients with carbohydrate intolerance were older, more obese, had higher 1-hour post-50 gm Glucola plasma glucose and glycosylated hemoglobin levels, and infants with increased birth weight percentiles, depressed 5-minute Apgar scores, and an increased incidence of shoulder dystocia and perinatal mortality.

Glycosylated hemoglobin as a screening test for carbohydrate intolerance in pregnancy.

The usefulness of glycosylated hemoglobin as a prenatal screening test for carbohydrate intolerance was studied in 806 consecutive subjects by correlating glycosylated hemoglobin to 1-hour post-50 gm Glucola plasma glucose (1 degree G) levels, and 3-hour oral glucose tolerance tests (3 degrees GTT). Sixty-seven subjects whose 1 degree G greater than or equal to 150 mg/100 ml received a 3 degrees GTT; 12 were diagnostic of carbohydrate intolerance. Compared to carbohydrate-tolerant controls, carbohydrate-intolerant gravid patients had higher 1 degree G (p less than 0.

Multilayer film analysis for glucose in 1-microL samples of plasma.

With the ultramicroanalytical system described here we can measure glucose in 1 microL of plasma or serum. The sample is placed on a dry, multilayer film element (Eastman Kodak), where a colored spot about 3.5 mm in diameter develops.

Reflectance digital matrix photometry.

We have designed and constructed a digital matrix photometer for quantitative measurement of reflected light of small chromophoric areas or colored spots. The areas are divided conceptually into small subunits in which the reflected light is measured. This is done through stepwise scanning with a photodiode array.

The abnormal outpatient chemistry panel serum alkaline phosphatase: analysis of physician response, outcome, cost and health effectiveness.

Physician response to, as well as outcome, cost and health effectiveness of the alkaline phosphatase component of an automated chemical screening panel in the primary medical care setting were studied. Out of 118 unexpected deviations, only one new diagnosis resulted--type A viral hepatitis. Because only one new diagnosis was made during the study period, estimates are tentative; however, when compared to other tests, the alkaline phosphatase component has a low health effectiveness (0.

A long-term study of the absorption of large oral doses of folic acid.

Large daily doses of oral folic acid ranging from 25 to 1,000 mg and totalling between 1,875 and 16,000 mg per course of treatment were well tolerated without any evidence of toxic effects by four hyperuricemic men of the ages of 26, 38, 46 and 50 years. The minimum folate absorption in the gut as measured by urinary excretion ranged from 10.1 to 45.

An instrument for digital matrix photometry.

A new instrument was conceived and designed for quantitative measurement of chromophoric areas or colored spots such as are produced in (e.g.) thin-layer chromatography.

Effects of naloxone-HCl on cortisol levels in patients with affective disorder and normal controls.

Cortisol levels were measured before and after administration of naloxone-HCl in patients with affective disorder (n = 16) and normal control subjects (n = 8). On two consecutive days, 20 mg of naloxone-HCl or placebo was administered i.v.

Failure of folic acid (pteroylglutamic acid) to affect hyperuricemia.

PGA administered in doses up to 1000 mg orally a day did not significantly lower the serum urate concentration nor decrease the urinary urate or total oxypurine excretion in five hyperuricemic subjects. The folate was well absorbed, as reflected by marked increases in the serum and erythrocyte folate concentrations, and up to 50% of the administered folate could be recovered in the urine. There was no evidence of clinical or laboratory toxicity at these high doses of folate.

Theoretical analysis of ligand-binder complex formation: partial equilibrium and incubation time.

This report presents a theoretical model of the rate at which complex formation approaches equilibrium in competitive binding systems while ligand concentration varies. Three commonly encountered systems are examined in which binder concentrations (q) are fixed at 0.5/K, 3/K and 50/K, respectively.

The weak binding reaction between folate and human serum proteins.

New evidence is presented that folic acid in serum binds with low affinity to major serum proteins. This low affinity binding is distinct from the high affinity binding by folate binding protein (FBP), a minor protein which is known to occur in serum with great quantitative variability. These conclusions are based on results obtained by equilibrium dialysis of serum containing only negligible amounts of FBP.

Blood lead levels in San Diego policemen.

Blood lead levels were measured by atomic absorption spectrophotometry in 86 San Diego policemen to see if they would reflect the known high atmospheric lead levels in San Diego. The mean blood lead for the entire group was 27.0 microgram per dl, a level very similar to that found in the general population of other cities.

Separation of folate binding protein from human serum by DEAE-cellulose column chromatography.

On diethylaminoethyl-cellulose column chromatography, the folate binding protein in the serum of 21 patients eluted in the early effluents as a single sharply defined peak. The chromatographic behavior of the folate binder remained unchanged whether or not the serum was, before chromatography, complexed with tritium-labeled pteroylglutamic acid ([3H]PGA), dialyzed, or charcoal-adsorbed. Heating to 100 degrees C for 10 min dissociated the [3H]PGA-binder complex while destroying the folate binding property.

Relative efficacy of separation of "free" and "bound" (3',5'-3H) pteroylglutamate by charcoal coated with various materials.

We studied the effectiveness with which various charcoal preparations separate free [3H]pteroylglutamate from that complexed with milk folate binder. We tested, in various concentrations, uncoated charcoals and charcoals coated with dextrans of various molecular weights, or with albumin, hemoglubin, or polyvinylpyrrolidone with an average molecular weight of 40 000. Althouth there was some distinction between the "bound" and "free" fractions with all charcoals, those treated with dextrans of average molecular weights of 43 500 or 70 000, or with polyvinylpyrrolidone gave the best separation over a greater range of charcoal concentration.