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Biomedical subjects

N I Ward

Publications and source records attributed to N I Ward.

31 records · Page 2Linked to original sources
PubMed1984

Fasting plasma magnesium concentrations and glucose disposal in diabetes.

Fasting plasma concentrations of magnesium were measured by neutron activation analysis in 30 non-diabetics and 87 diabetics (55 non-insulin-treated, 32 insulin treated). Plasma concentrations of magnesium were lowest in the insulin treated group (mean 0.84 (SEM 0.01) mmol/1; 2.0 (0.02) mg/100 ml), intermediate in the non-diabetics (mean 0.89 (SEM 0.01) mmol/1; 2.2 (0.02) mg/100 ml), and highest in the non-insulin-treated diabetics (mean 0.95 (SEM 0.02) mmol/1; 2.3 (0.05) mg/100 ml). In all diabetics plasma magnesium concentrations were inversely related to plasma glucose values (rs = -0.33; p less than 0.01) and in non-insulin-treated patients to plasma insulin concentrations (rs = -0.28; p less than 0.05), the former confirming previous observations. In 67 of the diabetics the KG constant for disposal rate of glucose during a standard intravenous glucose tolerance test was directly related to fasting plasma magnesium concentrations, and this relation persisted after controlling for age, sex, body mass index, type of treatment, and glucose and insulin values. This direct relation of plasma magnesium concentration with glucose disposal was unexplained by its influence on insulin secretion but was related to insulin sensitivity; hence magnesium may be an important determinant of insulin sensitivity in maturity onset diabetes.

Blood Glucose↗
PubMed1984

Tissue vanadium levels in manic-depressive psychosis.

The vanadium content of hair, whole blood, serum and urine was estimated by neutron activation analysis in samples from manic patients, depressed patients, recovered manic patients, recovered depressed patients and normal controls. The results suggest that manic patients have significantly raised vanadium levels in hair which fall towards control levels with recovery, but there are no significant differences in the mean vanadium content of whole blood or serum. In contrast, depressed patients have raised levels of vanadium in whole blood and serum which appear to fall with recovery. Levels of vanadium in serum correlate strongly with those in whole blood, but neither shows significant correlation with vanadium in hair for either patients or controls. Hair and blood probably serve as indicator tissues for differing aspects of vanadium metabolism.

Adult↗
PubMed1984

Elevated vanadium content of hair and mania.

Vanadium content of hair from manic patients, recovered patients, and normal controls was measured by neutron activation analysis. The mean vanadium content of the hair of the manic group was significantly higher than that of the control group and that of the group of recovered manics.

Adult↗
PubMed1978

Blood lead levels in sheep exposed to automotive emissions.

The lead content of whole blood of 62 sheep grazed continuously for 6 months near a major highway was compared with 38 sheep from a nearby uncontaminated area. Mean values of 0.90 and 0.20 microgram/ml were obtained. Four sheep from the contaminated area were placed in an uncontaminated paddock and the lead content of the blood decreased rapidly during the first 10 days and thereafter more slowly. After 185 days, blood lead levels had still not quite reached normal levels. Animal from an uncontaminated area showed an immediate rise in the blood lead levels when placed near a major highway. Sheep placed in a concrete pen away from motor vehicle exhaust emissions showed a rise in lead levels when fed with forage cut from the verges of a busy highway. Sheep placed near a highway and fed with forage from an uncontaminated area showed an increase of lead levels in the blood, comparable to that of the previous experiment. It was concluded that lead uptake by ingestion of polluted forage and by inhalation of airborne particulates are both mechanisms responsible for enhanced lead levels in ovine blood.

Animals↗
PubMedDate not supplied

Comparison of selenium levels in pre-eclamptic and normal pregnancies.

Abnormal placentation is the likely cause of the slow fetal growth and the high levels of circulating lipid peroxides found in severe pre-eclampsia. These peroxides are probably responsible for the high thromboxane:prostacyclin ratio found in this disease and may participate in the endothelial cell damage which is its most notable feature. Selenium (Se), because of its role in glutathione peroxidase, is suggested to be an important component of the removal system for these damaging peroxides. Serum-Se concentrations have therefore been measured in 19 pairs of pre-eclamptic women and matched controls. Infant birth-weights were recorded. No significant difference was found in the concentrations of Se in pre-eclamptic and control groups. Serum Se was found to be low in both groups. Birthweights were significantly lower in the pre-eclamptic group. The interpretation of serum-Se measurements from the third trimester of a pre-eclamptic pregnancy is complicated by the reduced fetal growth and probable lower Se take-up by the fetus in such a pregnancy. The merits of alternative measurements, such as total intravascular Se, placental Se, or samples from an earlier stage of gestation, are discussed. The importance of factors other than Se to the activity of glutathione peroxidase, and of other antioxidants to pre-eclamptic, is stressed.

Birth Weight↗
PubMedDate not supplied

Trace elemental content of biological materials. A comparison of NAA and ICP-MS analysis.

The advantages and disadvantages of neutron activation analysis (NAA) and inductively coupled plasma-source mass spectrometry (ICP-MS) for the analysis of biological materials is reviewed. Comparison is made between NAA (instrumental) and ICP-MS (conventional pneumatic solution nebulization and laser ablation) analysis of the biological reference material National Bureau of Standards (NBS) SRM 1577 Bovine Liver. Relatively good agreement is achieved between the results for the 18 elements analyzed by both techniques and those either certified or reported in the literature. Elemental concentrations for Li, Mg, Al, Ca, Cr, Mn, Fe, Cu, Zn, Br, Rb, and Cs are also reported for IAEA Mixed Human Diet (H9), NBS SRM 909 Human Serum, and NBS SRM 1577a Bovine Liver, analyzed by solution nebulization ICP-MS.

Animals↗
PubMedDate not supplied

Trace elements in manic depressive psychosis.

The concentrations of 16 elements (Al, Ba, Br, Ca, Cl, Cu, I, Pb, Mg, Mn, Mo, Rb, Se, Na, S and Ti) were estimated by neutron activation analysis in samples of hair, whole blood, serum and urine from normal controls, from patients suffering from mania and depression and from patients who had recovered from mania and from depression. Significant differences between groups were shown but apart from molybdenum, no element showed a significant change in more than one tissue. The differences in molybdenum concentrations appear to be of potential interest but the results must be interpreted with caution.

Adult↗
PubMedDate not supplied

Increased bromide levels in serum and hair during lithium treatment.

The concentration of bromide was measured by neutron activation analysis in samples of serum from 32 patients on maintenance lithium carbonate and from 32 age- and sex-matched controls. Whole blood and hair samples were also taken for analysis from a number of patients and controls. Bromide levels were found to be significantly higher in serum and hair of patients on lithium carbonate than in controls. The possible effects of this increase and the mechanisms causing it are discussed.

Adult↗
PubMedDate not supplied

Abnormal aluminium, cobalt, manganese, strontium and zinc concentrations in untreated epilepsy.

The concentration of 38 trace and bulk elements in the serum from 19 patients with recent onset of epilepsy and 20 age- and sex-matched controls was estimated by neutron activation analysis or inductively coupled plasma source by mass spectrometry. The concentrations of aluminium, strontium and zinc were significantly higher and the concentrations of cobalt and manganese were significantly lower than controls. Low concentrations of manganese and high concentrations of zinc in epilepsy have been previously reported but the abnormalities of aluminium, cobalt and strontium are new findings. The possible significance of these results in the pathogenesis of epilepsy is discussed.

Adult↗
PubMedDate not supplied

Lead and children.

Explore the source record for details and available documents.

Cadmium↗
PubMedDate not supplied

A comparison of low birth weight among Medicaid patients of public health departments and other providers of prenatal care in North Carolina and Kentucky.

Matching of Medicaid and health department patients' files to birth certificates was used as a means of evaluating the effect of prenatal care given by public health departments on the birth weights of babies of women in Medicaid. Three years of live birth data from North Carolina and 2 years of birth data from Kentucky were used in the analysis. After controlling for other low birth weight risk factors (including the quantity of prenatal care) with logistic regression, women in Medicaid who received prenatal care outside public health departments were found to be substantially more likely than those who received care at health departments to have low weight infants. This association was especially strong for births under 1,500 grams. The authors suggest that the comprehensive prenatal care that is provided by the public health departments, which includes various nonmedical support services, may be responsible for this difference. These findings have important implications for proposed expansions of the Medicaid Program to cover more pregnant women in poverty.

Black or African American↗