Search PubMed⌕ Search

Biomedical subjects

T Olsson

Publications and source records attributed to T Olsson.

At least 397 records · Page 22Linked to original sources
PubMed1983

Musculo-skeletal symptoms in early sarcoidosis. Twenty-four newly diagnosed patients and a two-year follow-up.

Musculo-skeletal symptoms were screened in 24 consecutive patients with newly diagnosed sarcoidosis and followed up two years later. Ten patients had joint involvement. Symptoms were most frequently found in ankle joints, followed by hand and knee joints. Arthritis was found in seven (29%) patients, two of whom suffered from monoarthritis of foot and wrist joint, respectively. Three patients had tenosynovitis. Muscle symptoms such as myalgia were present in six patients. Open biopsy of the gastrocnemius muscle showed epithelioid cell granulomatosis in nine of 20 patients. Only three of these nine patients had symptoms of myalgia, although not in the biopsied muscle. At follow-up, musculo-skeletal symptoms were found in only three patients, all of whom initially had Löfgren's syndrome.

Adult↗
PubMed1983

Methodological aspects on the firefly luciferase assay of adenine nucleotides in whole blood and red blood cells.

The firefly luciferase assay of adenosine-5'-triphosphate (ATP) is used in a simple procedure for the determination of adenine nucleotides in whole blood and red blood cells. Cells are lysed with cold trichloroacetic acid and nucleotides are determined in the lysate after dilution with buffer. In a comparative study with the spectrophotometric assay of ATP, extracts were prepared by centrifugation of the lysate to remove interfering turbidity. This step resulted in a significant loss of ATP in the clear supernatant. This loss could be avoided by determination of ATP by the firefly luciferase assay in diluted uncentrifuged lysates. The yields of ATP, ATP + ADP and ATP + ADP + AMP were compared in a red blood cell preparation after lysis with trichloroacetic acid and another lytic method based on the detergent triton X-100. The precision was better with acid whereas yields were essentially the same with both methods. The method of standardization, external or internal, was of little practical importance regarding yields and precision, but internal calibration is recommended to ensure that there is no interaction of the luciferase reaction with lytic reagent or sample.

Adenosine Diphosphate↗
PubMed1982

A sensitive method for determination of serum hemoglobin based on iso-luminol chemiluminescence.

A simple and rapid method for determination of serum hemoglobin is described. Hemoglobin may be determined in serum within the range of 0.02-400 mg/1 by the sensitive chemiluminescent iso-luminol reaction. The iso-luminol assay was considerably more sensitive than the conventional colorimetric procedure based on tetramethylbenzidine. Precision and accuracy were higher with the iso-luminol assay especially at low levels of hemoglobin. The correlation between the luminescent and colorimetric method was linear but the colorimetric determinations resulted in higher concentrations of hemoglobin. This discrepancy was probably caused by non-heme serum iron which interfered more strongly with the colorimetric method.

Benzidines↗
PubMed1982

beta 1-and beta 2-adrenoceptor stimulatory effects of prenalterol.

Prenalterol, previously characterized as a functionally cardioselective partial beta-adrenoceptor agonist, was shown to relax K+ -elicited contractures in the uterine muscle from progesterone pretreated rats (pD2 7.7) and to increase beating rate in the rat right atrium (pD2 8.0) at about the same concentrations with maximal effects corresponding to 94 and 82% respectively of those of isoproterenol. Terbutaline, with equal maximal effects as isoproterenol, was 50 times more potent in the uterus (pD2 7.8) than in the right atrium (pD2 6.1). Both tissues displayed a high sensitivity to isoproterenol (pD2 9.1 in both tissues) indicating large receptor reserves for the full agonist. The maximal relaxing effect of prenalterol in the uterus was obtained at about a three-fold increase of the cyclic AMP content, which is similar to that obtained with isoproterenol at a corresponding relaxation. The effects in the uterine muscle of all three agonists were mediated through beta 2-adrenoceptors since beta 2-adrenoceptor blockers (ICI 118, 551 and IPS 339) antagonized the effects in concentrations which had only marginal effects on the atrial responses of the agonists. The beta 1-antagonists pafenolol and pamatolol in concentrations higher than those, which blocked the effects of the agonists on beating rate, were devoid of inhibitory effects in the uterus. These results indicate that prenalterol possesses the ability to elicit a functional response by stimulation of either beta 1-or beta 2-adrenoceptors provided that the tissue has a large spare receptor reserve for full agonists.

Adrenergic beta-Agonists↗
PubMed1982

Demonstration of serum IgG antibodies against myelin during the course of relapsing experimental allergic encephalomyelitis in guinea pigs.

Chronic relapsing allergic encephalomyelitis (r-EAE) was induced in a local strain of guinea pigs. By the use of isoelectric focusing (IF) followed by antigen immunofixation and autoradiography, antibodies directed against central nervous system (CNS) myelin were detected in 21 of 23 sera sampled during the course of r-EAE. Previous absorption of the sera with CNS myelin reduced or abolished antibody activity on autoradiograms. One r-EAE guinea pig developed definite oligoclonal IgG bands in serum while in 7 r-EAE animals faint oligoclonal IgG bands were present. The mobility of oligoclonal IgG bands differed from the mobility of antimyelin antibody bands on autoradiograms. The significance of these findings has not been definitely elucidated but the antimyelin antibodies may possibly be involved in the pathogenesis of the disease while oligoclonal IgG bands may represent an epiphenomenon not pathogenetically related to r-EAE.

Animals↗
PubMed1982

A whole body autoradiographic study on the distribution of 14C-labelled di-(2-ethylhexyl)phthalate in mice.

Di-(2-ethylhexyl)phthalate (DEHP), a plasticizer used for polyvinylchloride polymers, has been reported to leach from blood transfusion bags and the plastic material in hemodialysis units into the blood. Phthalate esters are known to be hepatotoxic and teratogenic in experimental animals. Reports on the distribution and metabolism of DEHP indicate that the compound in largely excreted from the body within a few days. In the present investigation the distribution and tissue retention after administration of [14C]DEHP (carbonyl-14C or 2-ethylhexyl-1-14c) was studied in pregnant and non-pregnant mice with whole body autoradiography. Initially a high activity was observed in the brown fat, liver, gall bladder, intestinal contents, kidney and urinary bladder. Pretreatment with DEHP, phenobarbital sodium or 3-methylcholanthrene caused a relative increase of the activity in the brown fat, indicating that induced metabolic conversion of DEHP leads to an increased deposition of radioactivity in brown fat. After administration of DEHP (carbonyl-14C), but not DEHP (2-ethylhexyl-1-14C),marked retention was observed in the skin, cartilage and tendons. The mechanism responsible for the slow accumulation in these connective tissues is not known. In the early embryo a high concentration was observed in the neuroepithelium. This pronounced uptake may be correlated to the DEHP-induced malformations exencephaly and spina bifida observed in mice.

Animals↗
PubMed1982

Clinical application of evoked EEG responses in infants. III: congenital hypothyroidism.

Previous studies have shown a close relationship between maturation of the central nervous system and development of evoked EEG responses. In this study, 13 infants with congenital hyperthyroidism were examined between the ages of one week and 17 weeks in an attempt to evaluate the degree of developmental retardation and the influence of hormonal treatment. It was found that visual evoked responses were abnormal in 12 of the patients, the most common abnormality being an immature abnormal response pattern. Latency was increased significantly in 10 of the 11 patients who were diagnosed before the age of six months, but was normal in the remaining two who were diagnosed later. A significant reduction of photic driving occurred in only two patients; it was the sole abnormality in one of them. Both the response pattern and latency became normal during treatment. The authors conclude that recording visual evoked responses is a simple and useful method of evaluating cerebral function in congenital hypothyroidism, both before and during treatment.

Brain↗
PubMed1982

A scoring system for antenatal identification of fetal growth retardation.

A scoring system for selection of pregnancies at risk of intrauterine growth retardation (IUGR) is presented. It is based on eight weighted items which include information from previous pregnancies and from the current one including the increment of fundal height and of maternal weight. With a risk population of 7% all IUGR infants were included. The IUGR infants constituted 34% of the risk group.

Birth Weight↗
PubMed1982

Measurement of stroke volume with impedance cardiography.

Simultaneous determination of stroke volume with impedance cardiography and the dye dilution technique was compared in 11 healthy men before and after exercise. The correlation coefficient for all measurements was 0.82. Mean stroke volume determined by impedance cardiography was significantly (P less than 0.001) lower than mean stroke volume calculated by the dye dilution technique. However, there was no significant difference in the mean change in stroke volume determined by the two techniques during serial measurements. The reproducibility of single impedance-determined stroke volumes (6.9 ml) was not significantly different from single values obtained by dye dilution (7.3 ml). Impedance cardiography was found to be a safe, reliable, non-invasive method for the measurement of changes in stroke volume in healthy individuals before and after exercise. At present, direct estimation of absolute values of stroke volume is not recommended using impedance cardiography. Calibration of the impedance technique against other established techniques in a given application is necessary.

Adult↗
PubMed1981

Assessment of renal parenchymal thickness in normal children.

The normal range of variation of the parenchymal thickness in well defined parts of the kidney was determined in children (0 to 15 years). The values were correlated with the distance between the superior surface of L1 and the inferior surface of L3. The ratio between the parenchymal thickness on the right side and the left side was also determined. The results are compiled in two nomograms.

Adolescent↗
PubMed1981

Relation between blood resistivity and hematocrit in fresh human fetal blood.

This study determined the relation between hematocrit and resistivity of fetal blood and compared it with values obtained in similar studies on adult blood. Both exponential and Maxwell-Frick-estimated relationships were calculated and compared. The results indicate that there is no significant difference between resistivity in adult and fetal blood. The best relation between blood resistivity and fetal hematocrit is obtained by using the Maxwell-Frick estimated curve calculated in the following manner: (formula: see text).

Adult↗
PubMed1981

Peripheral nerve repair.

The neuron is remarkable as a cell with a prolonged process, the axon. Various substances and organelles are transported up and down the axon. Axotomy profoundly affects this axonal transport. The proximal stump of the axon seals off and organelles accumulate. Terminal sprouts appear and move towards the distal stump. Soon after reinnervation neurotransmission reappears. Initially polyneuronal innervation occurs but this is then eliminated. Somatopetal axonal transport has been studied using tracer macromolecules in the mouse facial neuron model. Transport was blocked by axotomy from terminals in muscle but persisted at the injured axonal membrane. This stopped when the axonal membrane grew over the stump. Transport returned after reinnervation. Such transport may carry the signals that govern neuronal response to axotomy.

Animals↗
PubMed1981

TULIPS: the Uppsala-Linkoping Image Processing System.

The Uppsala-Linkoping Image Processing System, TULIPS, is described. TULIPS, a hardware-software system designed for cell image processing, was developed at Uppsala University Hospital in cooperation with the Department of Electrical Engineering at Linkoping University. The hardware part of the image processing system is built around a high-speed data bus with a capacity of about 40 M byte/sec connected to a PDP-11/55 host computer. An image memory, an LSI-11 microcomputer and a video interface for displaying the image memory content on a TV monitor are also connected to the high-speed bus. An automated microscope and a "Poulsen processor" for low resolution segmentation, both to be attached to the high-speed bus, are being developed. A monitor and an interpreter for an image processing language have been implemented on the host computer. This software system allows interactive, as well as batch, processing. The degree of user interaction is easily adapted to the user's needs. The image processing language is command oriented, and it is easily expanded by adding new commands. The system has been used both for studies in the field of quantitative microscopy and as a platform for development and testing of new image processing algorithms.

Computers↗
PubMed1980

Cytophotometric quantification of retrograde axonal transport of a fluorescent tracer (primuline) in mouse facial neurons.

A method for cytophotometric quantifications of retrograde axonal transport of a fluorescent tracer in tissue sections is described. As a fluorescent tracer the anionic vital stain primuline proved to be suitable since it resulted in a strong yellow-green fluorescence, which faded very slowly permitting localization of cells during illumination with UV-light. Primuline injected into the muscles of the vibrissae in mice was transported to the corresponding nerve cell bodies in the facial nucleus, where it appeared as fluorescent granules 9 h after the injection. The fluorescence intensity increased with increasing exposure times and concentrations of the injected tracers. The motor endplates showed no ultrastructural changes after the tracer injections. The motor endplates showed no ultrastructural changes after the tracer injections. With this method a substantial increase in tracer accumulation in facial neurons could be revealed during nerve regeneration 11 days after crushing the facial nerve. Small alterations in neuronal tracer accumulation could be measured after intoxication of the mice with botulinum and tetanus toxins. Since these toxins should cause a decrease or increase in the degree of synaptic activity the amount of retrograde axonal transport may to a certain extent be dependent on the synaptic function. The findings with this new technique therefore indicate that quantitative changes occur in axonal transport in materials from the periphery during different pathological and physiological conditions, which may be important for an understanding of how a nerve cell body is dependent on its peripheral field of innervation.

Animals↗
PubMed1980

Impedance cardiographic assessment of symptomatic patent ductus arteriosus.

A modified impedence cardiographic technique was developed using a tetrapolar apnea monitor and minicomputer system. Evaluation of this technique in premature infants with and without symptomatic patent ductus arteriosus indicates that the magnitude of the cardiac-related deflection in the impedance signal is useful in the assessment of ductus shunting. Since the infant under study is involved only by the attachment of two double electrodes to the thorax, continuous assessment of ductur shunting is possible without disturbing routine care.

Cardiography, Impedance↗
PubMed1980

Somatopetal transport of horseradish peroxidase following incorporation into axonal sprouts and axons in neuromas after nerve transection.

Horseradish peroxidase (HRP) applied to the proximal stump of the facial nerve of the mouse 5 h after section diffused into the endoneurium and was incorporated by endocytosis into axons densely packed with organelles. By 24 h to 16 days after the section, uptake of the tracer into profiles of outgrowing axonal sprouts rich in vesicles and vacuoles was registered. Subsequently HRP accumulated in corresponding perikarya. Tracer transport from neuromas was demonstrated 32 and 64 days after section. In this way influences from outgrowing nerve sprouts and axons in neuromas may reach nerve cell bodies.

Animals↗
PubMed1979

Luminescence immunoassay (LIA): a solid-phase immunoassay monitored by chemiluminescence.

A luminescence immunoassay (LIA) has been developed utilizing the chemiluminescent luminol reaction with heme as catalyst. Rabbit antibody against human serum albumin was quantitated in antigen coated plastic tubes using commercially available goat anti-rabbit IgG conjugated to horseradish peroxidase which was the source of heme. The measurable range of antibody is considerably wider by LIA than by enzyme immunoassays. The time to develop and measure activity is short and constant which makes LIA suitable for automation. In its present form, LIA is slightly less sensitive but has better day-to-day reproducibility than corresponding enzymes immunoassays.

Immunoassay↗