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Biomedical subjects

S Poulsen

Publications and source records attributed to S Poulsen.

At least 73 records · Page 4Linked to original sources

Dental fluorosis among participants in a non-supervised fluoride tablet program.

The aim of the present study was to describe the intraoral pattern of dental fluorosis among fluoride tablet consumers. One hundred and forty-two children, of whom 56 had participated in a fluoride tablet program of 0.5/1.0 mg NaF per day were examined blindly for possible fluoride-induced enamel changes. A low prevalence of dental fluorosis was found among non-participants. The later in life the tooth was formed, the higher was the prevalence. The subjects who had participated in the fluoride tablet program showed a significantly higher prevalence of fluorosis. They could be divided into three groups: Group 1 exhibited a tooth prevalence pattern not statistically different from that of the non-participants, group 2 showed dental fluorosis in almost all teeth except in those formed before the start of the tablet program. In group 3 the early and the late formed teeth showed very little fluorosis while those formed in the few years just after the initiation of the fluoride tablet intake were affected by fluorosis.

Child↗

Concentrations of thyroxine, 3,5,3'-triiodothyronine, 3,3',5'-triiodothyronine, 3,3'-diiodothyronine, and 3',5'-diiodothyronine in human red blood cells.

A simple and rapid method for the estimation of cellular concentration of thyroxine (T4), 3,5,3'-triiodothyronine (T3), 3,3',5'-triiodothyronine (rT3), 3,3'-diiodothyronine (3,3'-T2), and 3',5'-diiodothyronine (3',5'-T2) as well as their distribution between cytosol and membranes in human red blood cells (RBC) is presented. Concentrations of iodothyronines in RBC (RBC-T) were calculated by multiplying the total serum concentrations by the ratio of radioactivity in equal volumes of packed RBCs and serum, pre-incubated with 125I-labelled iodothyronines of high specific activity. Plasma and RBC were separated by centrifugation in capillary glass tubes. The separation of membranes and cystosol was performed by hypotone lysis and centrifugation. The median RBC-T of T4, T3, rT3, 3,3'-T2, and 3',5'-T2 from 17 euthyroid subjects were 360 pmol/l, 156 pmol/l, 2.77 pmol/l, 6.81 pmol/l, and 2.17 pmol/l, respectively. The cytosol/cytosol + membrane ration were 66%, 40%, 84%, 77%, and 97%, respectively. The differences in RBC-T were not similar to the differences in free serum concentrations. The ratio of RBC-T to free serum concentration differed considerably between T4 (16.6), T3 (24.4), and 3,3'-T2 (15.5) as compared to rT3 (5.8) and 3',5'-T2 (2.6). Data on three patients with thyroid diseases suggested that RBC-T values were increased in hyperthyroidism and decreased in hypothyroidism, whereas the cytosol/cytosol + membrane-ratio was unaltered.

Adult↗

Interleukin-1 affects the function of cultured human thyroid cells.

Cytokines are peptide hormones essential for cellular communication in the immune response. The purpose of this study was to investigate the influence of cytokines, especially recombinant interleukin 1 beta (rIL-1 beta), on human thyroid cells. Thyroglobulin (Tg) was measured by a double antibody radioimmunoassay, and cyclic AMP (cAMP) by a competitive protein binding assay. Supernatants from unstimulated and phytohaemagglutinin-stimulated blood mononuclear cells were added to human thyroid cells cultured in monolayers. A dose-dependent inhibition of the secretion of Tg and cAMP was demonstrated. Both subcultured and primary cultured cells incubated with rIL-1 beta at pharmacological levels (10(-1)-10(2) U/ml) exhibited an inhibition of Tg and cAMP secretion, while at physiological levels (10(-5)-10(-3) U/ml), the secretion of Tg was enhanced. The similar stimulation of cAMP was demonstrated in subcultures. These in vitro studies suggest that IL-1 beta may play a role in the pathogenesis of autoimmune thyroid diseases. Further, the stimulations at low concentrations indicate that IL-1 beta may regulate the function of the thyroid gland under physiological conditions.

Autoimmune Diseases↗

Changes in prevalence of approximal caries in 17-year-olds and related restorative treatment strategies over a 6-year period.

Two cohorts of 17-yr-olds treated in a municipal child dental service in 1978-79 and 1984-85 had bitewing radiographs taken at the examination before the last course of treatment in the service. All radiographs were read by one examiner, who did not know to which cohort the individual belonged. The subsequent treatment was recorded from the treatment records by another examiner, who was unaware of the results of the radiographic examination. According to radiographic scores, the proportion of decayed or filled (DFS) approximal surfaces had decreased from 23.2% to 17.4% during the period (difference: 25%). The proportion of unfilled surfaces which were decayed (DS) had remained almost constant, while 9.6% of the surfaces were filled (FS) in 1978-79 compared to 3.1% in 1984-85 (difference: 68%). Thus, in spite of a 25% decrease in total caries experience (DFS), a reduction of 68% would be claimed if fillings (FS) were interpreted as expression of disease prevalence. The risk of an approximal surface being filled decreased to about one fifth from 1978-79 to 1984-85, and the risk of being filled was nearly three times as high for approximal surfaces of children who already had approximal fillings at the time of examination. Thus, both the year of examination and the subject's previously received treatment seemed to influence the treatment strategy of the dentist.

Adolescent↗

Longitudinal study of electrometric sensitivity of young permanent incisors.

Electrometric sensitivity of permanent maxillary central incisors was studied longitudinally in 34 children at 6-month intervals over 2 1/2 yr (mean age of the children at the beginning of the study: 94.6 months). Root development stages were determined from radiographs obtained at the beginning of the study, after 1 yr, and after 2 1/2 yr. An increase in sensitivity was found over the study period, but large variations were found from child to child and even within the same child. Especially at the first examinations a few children showed very low sensitivity. Statistical analysis showed that examination number, root development and side of the mouth (right or left central incisor) all were statistically significantly related to sensitivity. Statistically significant differences were also found between the individuals.

Child↗

Dental fluorosis in the primary and the permanent dentition in fluoridated areas with consumption of either powdered milk or natural cow's milk.

The aim of the present study was to describe the patterns of dental fluorosis in the primary and the permanent dentition of children born and reared in two different fluoridated areas, one in which powdered milk suspended in tap water was commonly used (Narssaq, Greenland: 1.1 ppm fluoride in the water) and one in which cow's milk was provided (Vordingborg, Denmark: 1.4-1.6 ppm fluoride in the water). Dental fluorosis was recorded by Thylstrup and Fejerskov's classification. In both locations, the prevalence of dental fluorosis increased the later in life the tooth type was formed. The prevalence of dental fluorosis in the earliest formed teeth was higher in the area where powdered milk was suspended in fluoride-containing tap water than where pasteurized cow's milk was used. In the first permanent molars, the maxillary incisors, and the canines, the prevalence was rather similar in the two areas. In the latest formed teeth, the premolars, the level of fluorosis was higher in Vordingborg. The pattern of dental fluorosis suggests that when powdered milk was used frequently, the children were exposed to a higher fluoride intake earlier in life than were those consuming cow's milk during infancy and childhood.

Adolescent↗

Thyroid hormone turnover in patients with small cell carcinoma of the lung.

Patients with small cell carcinoma of the lung often present with symptoms suggestive of hyperthyroidism i.e. weight loss without anorexia. Consequently [125I]T4 and [131I]T3 turnover was studied using simultaneously iv bolus injection and noncompartmental analysis in 6 patients with untreated small cell carcinoma of the lung and 14 normal subjects of comparable ages. Both T4 and T3 production rates were enhanced, T4 production being in median 135 nmol.day-1.70 kg-1 (range 111-200) in patients with small cell carcinoma of the lung vs 98 nmol.day-1.70 kg-1 (range 69-134) in controls (P less than 0.01), and T3 production being 46 nmol.day-1.70 kg-1 (range 33-65) vs 31 nmol.day-1.70 kg-1 (range 24-45) (P less than 0.01). The mean transit time was shortened for both T4 and T3, T4 mean transit time being 5.9 days (3.9-8.0 days) vs 8.3 days (6.1-11.2 days) in controls (P less than 0.01), and T3 mean transit time being 0.74 days (0.36-0.98 days) vs 1.03 days (0.81-1.45 days) in controls (P less than 0.01). Serum total and free T4 and T3 levels were unchanged. Basal serum TSH levels and the TSH response to iv TRH were also normal. Thyroid-stimulating immunoglobulins were only present in the serum in 1 of 6 patients. Thus, thyroid hormone production seemed under pituitary regulation. The peripheral effect of thyroid hormones was evaluated measuring serum sex hormone binding globulin levels, which were increased to in median 270% (77-310%) (P less than 0.01) of that in controls, suggesting some degree of hyperthyroidism in liver tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Patterns of dental fluorosis in a European country in relation to the fluoride concentration of drinking water.

Dental fluorosis among 456 14-16-year-old schoolchildren who had resided continuously since birth in their respective study areas was recorded using the Thylstrup and Fejerskov classification system. The children fell into four groups according to fluoride concentration of their drinking water: (1) less than or equal to 0.1 ppm; (2) 0.3-0.5 ppm; (3) 0.5-1.25 ppm; and (4) 1.26-2.0 ppm. It was found that the later in childhood the tooth was formed, the higher was the prevalence of dental fluorosis. The fluoride concentration in the drinking water affected the prevalence of dental fluorosis in all teeth except the lower incisors, which are formed very early in life. Apart from these teeth, the proportionate increase of dental fluorosis with increasing water fluoride concentration was almost the same for all tooth types. However, the actual amount of increase in the prevalence and degree of fluorosis was greatest among those teeth that formed later during childhood. The observed fluorosis is presumed to result from and reflect the drinking water habits in the population as well as the patterns of use of fluoride prophylactics.

Adolescent↗

Relationships between serum thyrotropin, serum free thyroxine (T4), and 3,5,3'-triiodothyronine (T3) and the daily T4 and T3 production rates in euthyroid patients with multinodular goiter.

Serum TSH, as measured by a sensitive assay, and serum free T4 and T3, as measured by an ultrafiltration technique, were compared in 14 euthyroid patients with multinodular goiter and 14 normal subjects. T4 and T3 turnover studies also were performed, using the single injection, noncompartmental approach. The goitrous patients had serum free T3 levels within the normal range, but their median serum T3 level was increased compared to that in the normal subjects [goitrous patients, 5.48 pmol/L (range, 4.41-9.03); normal subjects, 4.12 pmol/L (range, 2.58-5.78); P less than 0.01]. The T3 production rate (PR) also was elevated in the patients (median, 39.4 nmol/day X 70 kg; range, 28.7-70.5) compared to that in the normal subjects 31.1 nmol/day X 70 kg; range, 24.4-45.2); P less than 0.05). No differences were found between the two groups with regard to serum free T4 levels or T4 PRs. Serum TSH levels in the patients were reduced (median, 0.20 mU/L; range, less than 0.05-1.6) compared to those in normal subjects (1.8 mU/L; range, 0.36-5.1; P less than 0.01). A significant inverse correlation was found between serum TSH levels and free T3 levels (r = 0.70; P less than 0.001), whereas serum TSH did not correlate with serum free T4 or the PR of T4 or T3. Our data suggest that clinically and biochemically euthyroid patients with multinodular goiter have slight T3 hyperproduction, and TSH secretion in the patients studied was more closely related to serum free T3 levels than to serum free T4 levels or the T3 or T4 PR.

Adult↗

The influence of free fatty acids on the free fraction of thyroid hormones in serum as estimated by ultrafiltration.

Thyroid hormones are displaced from their binding proteins in serum during nonthyroidal somatic illness, and FFA have been claimed to contribute. It seems mandatory to evaluate this effect using techniques for the measurements of serum free thyroid hormones in which serum remains undiluted. We measured the effect of 7 common human FFA on the free fraction of T4, T3 and rT3 in serum from healthy subjects using an ultrafiltration technique by which serum is diluted only minimally. In addition we measured the effect of oleic acid on the free fractions of the iodothyronines in pooled serum from healthy subjects and in pooled serum from patients with nonthyroidal illness. All FFA tested were able to displace both T4, T3 and rT3, but to a varying degree, arachidonic and linoleic acid being the most potent ones. A 20% increase in the free fractions of T4, T3 and rT3, respectively, was obtained by adding between 1.7-3.3 mmol/l, 1.3-4.6 mmol/l and 1.0-2.4 mmol/l of the different FFA. A serum pool obtained from patients with nonthyroidal somatic illness was more sensitive to oleic acid than a serum pool obtained from healthy subjects, since 2-3 times less oleic acid was necessary to induce a 20% increase in the free fractions of thyroid hormones. It is concluded that FFA are able to displace both T4, T3 and rT3 from their serum binding proteins in healthy subjects as well as in patients with nonthyroidal illness. However, serum from patients with nonthyroidal illness was more sensitive to the displacing activity of oleic acid than serum from healthy subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebrovascular Disorders↗