Search PubMed⌕ Search

Biomedical subjects

B Steen

Publications and source records attributed to B Steen.

At least 127 records · Page 7Linked to original sources
PubMed1986

Factors influencing participation in health surveys. Results from prospective population study 'Men born in 1914' in Malmö, Sweden.

Base line data together with data in public registers and a structured phone interview of 94 of the 121 non-attenders was used for an assessment of factors influencing participation in the prospective population study 'Men born in 1914' in Malmö, Sweden. The overall attendance rate was 80.5% but varied among areas in the city from 27% to 100%. The lower participation rate among single men remained, when correcting for social class, significant only for single men in social class III. Men who did not feel well and/or had been admitted to hospital during the last 12 months had a lower participation rate. A negative attitude towards health surveys in general was the most common reason for non-participation. The phone interview turned out to be a feasible method to reach non-attenders to assess whether the sample was representative of the population and to learn more about reasons for non-participation.

Aged↗
PubMed1986

Health, disorders, and drug consumption in an elderly population in northern Sweden.

A population study of health state, care, and drug consumption among 187 70-, 75-, and 79-year-old persons in Umeå, Sweden, was performed. It was shown subsequently that women felt less healthy and had a higher drug consumption than men, while concerning definable diseases there was no sex difference. Only 13% of the subjects were considered medically healthy, i.e., without definable diseases. 69% had been hospitalized over the age of 60 years.

Age Factors↗
PubMed1984

Blood components in an elderly population.

The reference intervals of 18 blood components were established for an elderly population in the 8th decade of life. The most significant findings were a broader range of values for most of the components, lower values of plasma folate and plasma potassium and higher values of erythrocyte sedimentation rate, plasma creatinine and serum cholesterol, the lattermost in women only, compared to younger people.

Aged↗
PubMed1983

Pharmacokinetics of metoprolol and its metabolite alpha-OH-metoprolol in healthy, non-smoking, elderly individuals.

The absorption and disposition of metoprolol have been evaluated in 10 healthy, non-smoking, elderly individuals (mean age 73.1 years) by simultaneous determination of [3H]-metoprolol and unlabelled metoprolol. The labelled drug was given as an intravenous tracer dose, immediately followed by oral metoprolol 25 mg. The experiment was preceded by administration of metoprolol 25 mg b.i.d. for 3 days. The volume of distribution, elimination half-life and total body clearance were almost the same as previously observed in healthy, young subjects. The mean systemic availability was about 39% in the elderly, which is lower than the mean of 55% observed in a control group of young volunteers who received 50 mg b.i.d. In the elderly, the mean plasma concentration of alpha-OH-metoprolol was about twice as high as that of the parent drug, whereas the opposite was true of the control group. The results indicate that age-related physiological changes have a negligible effect on the pharmacokinetics of metoprolol.

Adult↗
PubMed1983

Chemical and biological characterization of emissions from coal- and oil-fired power plants.

Emission samples were obtained from two medium-sized power plants, one fired with oil and the other with pulverized coal. Particles obtained by a miniscale plume stack gas sampler (MIPSGAS), simulating the dilution process in the plume, were subjected to detailed physical, chemical and biological characterization. Studies by scanning electron microscopy and by Coulter counter demonstrated that the particles from the oil-fired boiler were considerably larger than the particles from the coal-fired boiler. Chemical analyses revealed more organic substances and more S, Ni, V, in the oil than in the coal particles. The latter contained a larger proportion of Al, Si, Cl, K, Ca, Ti, Mn, Fe, Se, Rb, Y, Zr, Ba and Pb. Biological testing revealed a greater acute and subacute toxicity by the intratracheal route in the hamster, a greater toxicity to alveolar macrophages and a greater lung retention of BaP coated on the particles from oil combustion than on those from coal combustion. In another sampling line, employed simultaneously with the MIPSGAS-particulate sampler, the total emissions were collected, i.e., both particle and gas phase. These samples were used for chemical analyses and Ames mutagenicity test. Analyses of specific PAHs in emissions from both plants demonstrated that concentrations were below the detection limit (less than 4 ng/m3 of benzo(a)pyrene), which is in accord with an efficient combustion of the fuel. The mutagenicity of the samples were below the detection limit of the mutagenicity assay.

Air Pollutants↗
PubMed1982

Tobacco smoking, ageing and health among the elderly: a longitudinal population study of 70-year-old men and an age cohort comparison.

In the population study Seventy-year-old People in Göteborg, 449 70-year-old men were examined in 1971/72. Out of these, 331 were re-examined in 1976/77 at age 75, together with a cohort-comparison group of 474 70-year-old men. Cohort differences and a lower smoking prevalence at higher ages were observed. The loss of body weight after the age of 70 was higher in smokers and was not due to differences in energy intake. The levels of certain blood components showed differences among smokers compared to non-smokers, indicating an influence on liver metabolism and on the hormone function. Tobacco smoking was not only related to ill health but also to an impaired functional capability in bone mineral density, pulmonary function and muscle strength.

Aged↗
PubMed1982

Phenytoin excretion in human breast milk and plasma levels in nursed infants.

Phenytoin excretion into human breast milk was studied in six nursing women with epilepsy. The average ratio between the areas under the plasma (and milk) concentration versus time curves (AUC) was 0.13. There was a good (r = 0.97) correlation between the mean plasma and milk concentrations of phenytoin, and an even better relation (r = 0.99) between the AUC for phenytoin in plasma and the mean milk concentration. The ratio between unconjugated and conjugated 4-OH-phenytoin (the main metabolite) in plasma was 0.08-0.09. The corresponding ratio in milk was considerably higher. The present data do not argue against breast feeding during phenytoin therapy, not even when weighed against the potential risks for toxicity of the parent compound. Only two of six infants had a measurable, yet very low plasma concentration of phenytoin. The calculated body weight--related doses of phenytoin secreted into milk will be less than 5% of the dose to infants and small children.

Adult↗
PubMed1982

Relationship between dental state and dietary intake in 70-year-old males and females in Göteborg, Sweden: a population study.

A representative sample of 368 70-year-old males and females in Göteborg, Sweden, participated in an odontological examination and a dietary interview. The aim of the study was to relate dental state to dietary habits and, furthermore, to study the possible influence of some social factors on these relations. The degree of dental invalidity was measured with Eichner's index. There was a highly significant correlation between this index and the number of teeth and tooth contacts. Dietary interviews were performed by a dietitian according to the dietary history method. Intake of several food items was significantly inversely related to the degree of dental invalidity in males but less so in females. The proportion of probands with insufficient intake of nutrients was in one or more respects higher among the edentulous than in the dentate and highest in the female edentulous probands with only one or no denture. Insufficient intakes of some nutrients were significantly related to the degree of dental invalidity. These relations remained unchanged in males but not in females when some socio-economic factors were introduced as confounding factors in a multivariate relation analysis; which might be due to the fact that these social factors play a more important role in females than in males.

Aged↗
PubMed1981

Hypokalemia--clinical spectrum and etiology.

This paper is intended to give a review of the etiology and symptoms of potassium deficiency in man, as an introduction to the section on potassium and cardiac arrhythmias of this symposium. A review is given of different conditions where hypokalemia and/or total potassium deficiency is or might be part of the clinical picture, such as conditions with insufficient dietary intake, gastrointestinal potassium losses (e.g. vomiting, fistulas, malabsorption, abuse of laxatives and diarrhea), and renal potassium losses (e.g. primary and secondary hyperaldosteronism, Cushing's syndrome, intake of licorice, diabetic coma, renal disease, diuretic treatment and l-dopa treatment). Common symptoms of hypokalemia and/or potassium deficiency are reviewed as well, such as general and unspecific symptoms (e.g. tiredness, lack of concentration, lack of appetite and vomiting), and symptoms from the heart, kidneys and skeletal muscle.

Diet↗
PubMed1981

Glutathione and gamma-glutamyl cycle enzymes in human fetal liver.

Human fetal and adult liver were found to have similar concentrations of acid soluble sulfhydryl (SH) groups (7.4 mmol/kg) in the same range as is found in adult mouse and rat liver. The concentration was 4-fold higher than in human fetal adrenal gland tissue. Methods specific for glutathione (GSH) associated SH groups revealed that the postmortem levels of GSH is very low (0.4 mmol/kg) in relation to total SH groups. In contrast, the levels of cysteine were high (2.8 mmol/kg), indicating a rapid cleavage of GSH. Only negligible amounts of gamma-glutamylcysteine and cysteinylglycine were measured. Our findings may be explained by high fetal activity of gamma-glutamyl transpeptidase (which metabolizes GSH) that has been documented previously both in man and in experimental animals. High activities of the two GSH-synthesizing enzymes, gamma-glutamylcysteine synthetase and GSH synthetase were found in the human fetal liver (7.1 and 3.0 mukat/kg, respectively). The activities of these enzymes were in the same range as in human adult liver, whereas that of gamma-glutamyl transpeptidase was 3-fold higher in the fetal liver. Our results demonstrate the presence of high concentration of SH groups and capacity to synthesize GSH already in the first and second trimester of the human fetal gestation. This has more than theoretical interest, since we assume that the SH groups (GSH) have importance for the protection of the fetus against drugs and foreign compounds and their (toxic) metabolites, the formation of which is catalyzed by the fetus itself.

Adrenal Glands↗