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S Thunell

Publications and source records attributed to S Thunell.

54 records · Page 3Linked to original sources
PubMed1984

Age-related differences in the serum prolactin response during standardized surgery.

The aim with the present study was to assess possible age-related differences in the serum prolactin, cortisol and blood glucose responses to standardized surgical stress in humans. Relatively healthy men suffering from inguinal hernias were selected. The subjects were divided into a group of younger people (M=36.4 years, r=23-45, n=7) and one of older people (M=66.5 years, r=56-75, n=9). Surgery was carried out under general anesthesia. Blood was drawn before, during and following the operation. Blood pressure and pulse rate were also monitored. No differences were noticed in plasma prolactin, cortisol, and blood glucose during basal conditions. Even though plasma prolactin increased significantly in both groups during surgery, it was higher in the younger group (M=56.2 micrograms/1) as compared with 28.7 micrograms/l for the older group, p less than .01. Plasma prolactin during surgery, but not under basal conditions, correlated inversely with age. No differences between groups were found during surgery in blood glucose and serum cortisol. This study indicates a diminished stress response in older subjects, possibly due to age-related neuroendocrine changes.

Adult↗
PubMed1984

A filter paper dry blood spot procedure for acute intermittent porphyria population screening by use of whole blood uroporphyrinogen-I-synthase assay.

A filter paper dry blood spot procedure for the determination of whole blood uroporphyrinogen-I-synthase (UIS) activity is presented. The method is based on the concept of enzyme specific activity, the enzyme activity being related to the haemoglobin concentration of the assay sample. The diagnostic capacity with regard to the acute intermittent porphyria (AIP) gene carrier state is shown to be equivalent to that of a washed red cell reference method. On grounds of easy capillary blood sampling, uncomplicated and safe mail specimen transport and simple laboratory reception routines, the method is stated to be well adapted for use in AIP preadolescent population screening.

Adolescent↗
PubMed1983

Genetic regulation of the red cell uroporphyrinogen-I-synthetase level in families with acute intermittent porphyria.

The uroporphyrinogen-I-synthetase (UIS) activity in red blood cells was determined in 206 individuals from 48 nuclear families ascertained through a proband with acute intermittent porphyria (AIP) as well as in 230 members belonging to 53 nuclear families with no signs of AIP. Complex segregation analysis showed that the UIS activity is regulated by a major locus (a dominant or additive gene) together with a considerable multifactorial component.

Ammonia-Lyases↗
PubMed1982

Platelet factor 4 plasma levels at rest and after exercise in patients with recent myocardial infarction.

Plasma levels of platelet factor 4 (PF 4) were determined in 30 patients with recent acute myocardial infarction. Comparisons were made with the levels in 26 age-matched controls. In another 15 patients, also with recent myocardial infarction, PF 4 plasma levels were determined before and immediately after a standardized exercise stress test. At rest, none of the patients had elevated PF 4 levels. Only one patient demonstrated an increase after exercise. These findings are in conflict with some recent reports. The importance of age-matched controls, the hazard of in vitro platelet activation and the possible effect of beta-blocking and calcium-antagonistic drugs on PF 4 plasma levels is discussed below.

Aged↗
PubMed1982

Enhanced in vivo platelet activation in diabetes mellitus.

Plasma levels of platelet factor 4 (PF4) determined in 58 apparently healthy subjects were found to increase with age. In 66 insulin dependent diabetics, PF4 plasma levels were increased but unrelated to the age of subject. Mean fibrinopeptide A levels were elevated in the diabetics but not correlated to PF4 levels. Activation of the coagulation system with thrombin generation thus seems to be operative in diabetes, but the enhanced platelet activation also observed in this disease is probably not thrombin mediated. No correlation was found between PF4 plasma concentration and the degree of vascular complication, HbA1C, blood glucose, 24-h urinary glucose, serum cholesterol or serum triglycerides.

Adult↗
PubMed1982

Why is the patient with acute intermittent porphyria not light sensitive?

Acute intermittent porphyria (AIP) belongs to the group "inborn errors of metabolism". The disease is inherited as an autosomal dominant gene and characterized by abdominal, neurological and neuropsychiatric symptoms. The basic defect in AIP is assumed to be a mutation in the genetic system which controls the uroporphyrinogen-I-synthetase (UIS) activity. The UIS activity in erythrocytes is about 50% lower in gene carriers than among their non-porphyric siblings. The metabolic block in the haem synthesis is situated between porphobilinogen and uroporphyrinogen and leads to high levels of porphyrin precursors but no accumulation of porphyrins. Since the porphyrin precursors do not cause light sensitivity and tissue porphyrins are not markedly increased most patients with AIP are not light sensitive.

Child↗
PubMed1981

Follow-up of women with large-for-dates infants. Early insulin and C-peptide response to intravenous glucose, blood lipids and HLA-types.

In a previous study we determined the glucose disappearance rate (kt) in 129 newborn large-for-dates infants (LFD) born to mothers without known diabetes. Twenty-six infants (i.e. 20.6%) had elevated kt values similar to those in offspring of diabetic mothers. A follow-up study of 123 of these mothers was performed 7 years after delivery and included determination of early insulin and C-peptide response to intravenous glucose, plasma concentrations of 3-hydroxybutyrate, cholesterol, triglycerides, lipoproteins and HLA-typing. Two subjects had developed diabetes and altogether 14% had a kt below 1.0. Measures of the early insulin and C-peptide response to glucose were equally well correlated to maternal kt values (r = 0.40, P less than 0.001). Measures of the early insulin and C-peptide responses were significantly correlated (r = 0.64, P less than 0.001). The frequency distribution of HLA antigens were not different from normal and there was no association between HLA-B8 or B15 and impaired insulin response or glucose tolerance. Multiple regression and discriminate analysis of clinical and biochemical variables could not accurately identify women with high or low kt values. Multiple regression analysis using infant kt value as the dependent variable disclosed only a weak, but significant, inverse association to maternal insulin response to glucose at follow-up.

Adult↗
PubMed1979

Bacteriuria diagnosis and antibiotic susceptibility testing in a group practice by dipslide techniques.

In group practice, screening for bacteriuria and antibacterial susceptibility testing of bacteria in urine specimens were performed by dipslide methods (Uricult and Sensicult, Orion Diagnostica) and the results were evaluated with respect to conventional cultivation of urine specimens and standardized susceptibility testing by the disc diffusion method at a bacteriological laboratory. Bacteriuria diagnosis by screening by the Uricult method seemed to be satisfactorily performed except for some streptococcal strains. In the case of direct susceptibility testing by the Sensicult dipslide method, however, the results obtained by personnel at the surgeries and by trained bacteriologists displayed unacceptable disparities, despite the fact that a continuously running training programme was established.

Anti-Bacterial Agents↗
PubMed1977

A gel filament as an analytical tool: the testing of an affinity chromatographic, product-immobilizing linear gel for determination of enzymatic activity.

A new technique for quantitative analysis is proposed. An underfined volume of the test solution is exposed to a reagent in the form of a gel filament of capillary dimensions. The linear progress in the gel of the compound in question is followed with the aid of the coloured reaction products deposited along its path. With the use of the enzyme gamma-glutamyl transpeptidase it is shown that the velocity in the system of the component to be analysed, as determined by measurement of its coloured track, is related to its activity in the test solution.

Aniline Compounds↗
PubMed1977

Thin-layer chromatographic procedure for the detection, isolation and identification of basic psychotropic drugs in urine.

A procedure is described for the detection and identification of basic psychoactive drugs in urine. In the analytical system proposed, detection is dependent on thin-layer chromatography and chromophoric spraying of the resulting chromatogram. Identification is based on the extractability of the compound at the pH applied, on RF values in two solvents, on colour characteristics after exposure to a sequence of reagents, on fluorescence and UV-absorption characteristics, on retention times in different gas-liquid chromatographic systems and on the behaviour in ion-pair extraction with methyl orange. The procedure has been applied to some narcotic alkaloids and amines which exhibit central stimulant action.

Alkaloids↗
PubMed1976

Antibacterial susceptibility testing by the dip-slide technique: a methodological evaluation.

Antibacterial susceptibility testing of urine specimens by the dip-slide method was compared to the standardized disc diffusion method. A boarder line of 12 mm inhibition zone on the slide could be used to select strains resistant to sulphisadimidine, ampicillin, nitrofurantoin or nalidixic acid. In the case of the sulphonamide, the results were grewtly influenced by composition of the medium. Susceptibility testing with the dip-slide method seems to be a useful test to differentiate strains likely to respond to therapy from resistant strains.

Ampicillin↗
PubMedDate not supplied

Porphyrin status in aluminum foundry workers exposed to hexachlorobenzene and octachlorostyrene.

The possible interference of hexachlorobenzene and octachlorostyrene (i.e., thermal byproducts from hexachloroethane in aluminum degassing) with porphyrin metabolism was investigated in exposed workers. Urine specimens from 9 male aluminum foundry workers (i.e., smelters) at 6 different companies and from 18 controls-matched for sex, age, residence, and socioeconomic status-were analyzed for total porphyrins and porphyrin isomers. Workers exposed to hexachlorobenzene and octachlorostyrene had a statistically significant increase in urinary total porphyrins, compared with controls (mean +/- standard deviation: 13.63 +/- 11.13 micromol/mol creatinine and 6.24 +/- 3.84 micromol/mol creatinine, respectively; p = .02). The authors attributed the results mainly to differences in excretion of coproporphyrins-notably coproporphyrin III. Erythrocyte uroporphyrinogen decarboxylase activity was similar in both groups. There was a high correlation between levels of hexachlorobenzene and octachlorostyrene, respectively, in plasma and urinary excretion of porphyrins; these findings, however, relied heavily on 1 subject for whom extreme values were obtained. The results indicated that occupational exposure to hexachlorobenzene and octachlorostyrene in aluminum degassing with hexachloroethane may affect porphyrin metabolism in a manner consistent with early secondary coproporphyrinuria-the first recognized step in the development of chronic hepatic porphyria. It was also noted that changes remained detectable some years after exposure ceased.

Adult↗