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Biomedical subjects

T Olsson

Publications and source records attributed to T Olsson.

At least 379 records · Page 21Linked to original sources
PubMed1985

HLA-DR expression, T lymphocyte phenotypes, OKM1 and OKT9 reactive cells in inflammatory myopathy.

Frozen muscle biopsy sections from 13 patients with inflammatory myopathy and from four healthy volunteers were characterized with a double immunohistochemical staining technique, utilizing a panel of antisera to cell surface antigens. The technique enables simultaneous visualization of HLA-DR reactive cells and other cell types, i.e., T lymphocytes. In inflammatory myopathy, large numbers of HLA-DR reactive "macrophage/dendritic" cells were shown. Almost all other inflammatory cells and endothelial cells also expressed HLA-DR, as did the sarcolemma in the vicinity of inflammatory foci. Large numbers of T lymphocytes were detected by alphaLeu-1 antibodies. In most instances, Leu-3a reactive T "helper" lymphocytes dominated over alphaLeu-2a reactive T "suppressor/cytotoxic" lymphocytes. Many T lymphocytes of both phenotypes appeared in close contact with HLA-DR expressing non-T cells. OKM1 and OKT9 antibodies, labeling macrophages and "proliferating" cells, respectively, were common among inflammatory cells. The findings provide basic data that are important for the understanding of inflammatory myopathy.

Adolescent↗
PubMed1985

In vitro synthesis of immunoglobulins and autoantibodies by lymphocytes from various body compartments during chronic relapsing experimental allergic encephalomyelitis.

Mononuclear cells extracted from regional lymph nodes, blood, spleen and central nervous system of guinea pigs with chronic relapsing experimental allergic encephalomyelitis (r-EAE), adjuvant immunized and untreated controls were cultured for 16 h in microtitre plates, and culture supernatants were then used to measure IgG and IgM, as well as IgG class anti-myelin antibody production by enzyme-linked immunosorbent assays. Increased synthesis of these immunoglobulins and antibodies was found during the course of r-EAE both in intra- and extrathecal compartments. Long-term cultures carried out for 7 days gave similar results but anti-myelin, anti-myelin basic protein and IgG synthesis was most pronounced intrathecally. Agarose isoelectric focusing of supernatants from these cultures showed oligoclonal IgG. These findings indicate in vivo synthesis of autoantibodies within the target for immune attack and a partial sequestration of the immune response to this compartment.

Animals↗
PubMed1985

In vivo treatment of rats with monoclonal anti-T-cell antibodies. Immunohistochemical and functional analysis in normal rats and in experimental allergic neuritis.

The effects of intraperitoneal injection of monoclonal anti-rat T-lymphocyte antibodies were evaluated immunohistochemically and functionally in normal rats and in rats with experimental allergic neuritis. In the normal animals a single injection of OX8 antibodies, reactive with suppressor/cytotoxic T cells, completely eliminated OX8-reactive cells from peripheral lymphoid organs and from circulation, whereas the 'pan' T-cell-reactive W3/13 antibodies and the helper T-cell-reactive W3/25 antibodies only caused a partial elimination of their respective target cells. Injection of the W3/13 and W3/25 antibodies but not of OX8 antibodies led to a diminished responsiveness to allogeneic stimulation in vitro for spleen cells obtained from the treated rats, whereas the OX8 injection caused a complete elimination of the in vitro cytotoxic response to allogeneic cells in the mixed lymphocyte reaction-activated spleen cell population. When Lewis rats were injected with peripheral nerve myelin and Freund's adjuvant for the induction of EAN, treatment with W3/13 antibodies completely prevented the onset of disease, whereas treatment with the OX8 antibodies exaggerated the disease symptoms.

Animals↗
PubMed1985

Detection of C polysaccharide in Streptococcus pneumoniae in the sputa of pneumonia patients by an enzyme-linked immunosorbent assay.

The pneumococcal C polysaccharide (PnC) is species specific and believed to be a cell wall component of all pneumococcal types. A sandwich enzyme-linked immunosorbent assay (ELISA) for detection of PnC in sputa has been developed by using a monoclonal antiphosphorylcholine antibody and a polyclonal rabbit anti-PnC antiserum in the test system. A 1-year study of adult hospitalized patients with community-acquired pneumonia was performed. A total of 147 patients with clinical and radiological evidence for pneumonia were accepted for the study. Of these, 105 patients provided a sputum sample upon admission to the ward. The sputa were cultured semiquantitatively as well as tested for the presence of antigen. Of the sputum samples from patients with Streptococcus pneumoniae, 27 of 33 (accounting for a sensitivity of 82%) were positive in the ELISA test. Of the sputum samples from patients with pneumonia of some other known or suspected etiology, 32 of 34 (accounting for a specificity of 94%) were negative. In addition, 7 sputum samples from 31 patients with pneumonia of unknown etiology were positive. The ELISA test described here is in our opinion a sensitive and specific test for detecting PnC from S. pneumoniae in sputa from patients with untreated pneumonia.

Adult↗
PubMed1985

Cerebrospinal fluid immunoglobulin abnormalities in systemic lupus erythematosus.

Central nervous system (CNS) involvement is a common and important complication in systemic lupus erythematosus. The mechanisms for CNS involvement are poorly understood and reliable diagnostic procedures are lacking. Pairs of serum and cerebrospinal fluid (CSF) specimens from 17 patients with clinical and serological manifestations of systemic lupus erythematosus were analysed. All 11 patients with definite or suspect clinical CNS disorder revealed some kind of abnormality in the CSF, in contrast to three of seven systemic lupus erythematosus patients without CNS disorder. The most prominent findings in systemic lupus erythematosus patients with CNS disorder were immune aberrations with oligoclonal bands on agarose isoelectric focusing (AIF) and elevation of IgG and IgM index, probably reflecting intrathecal production of IgG and IgM respectively. Intrathecal production of antiviral antibodies was found in four of 12 patients by AIF followed by immunofixation and subsequent autoradiography. An enzyme-linked immunoabsorbent assay (ELISA) could not detect autoantibodies against structural brain antigens.

Adolescent↗
PubMed1984

Chemiluminescent immunosorbent assay of serum myoglobin based on the luminol reaction.

A simple and sensitive method for the determination of serum myoglobin is described. Myoglobin was determined in the range of 10-500 micrograms/1 by the chemiluminescent luminol reaction after adsorption to anti-myoglobin IgG onto a solid phase. Only 50 microliter of serum has to be used and the luminescent immunoassay (LIA) has a better sensitivity and a wider linear range than the conventional radioimmunoassay (RIA). However, in its present form LIA has a higher imprecision than RIA. In clinical specimens the correlation between the two methods was excellent.

Antibody Specificity↗
PubMed1984

IgM and IgG responses during chronic relapsing experimental allergic encephalomyelitis (r-EAE).

During chronic relapsing experimental allergic encephalomyelitis (r-EAE) in guinea pigs, serum IgM and IgG concentrations increased markedly early in disease. Serum IgM and IgG increased similarly in control animals immunized with Freund's incomplete adjuvant (FIA) and Mycobacterium tuberculosis (MT). In the chronic phase of r-EAE but not in control animals, elevated IgM was also found in central nervous system (CNS) extracts, suggesting intrathecal IgM synthesis. IgG antibodies against myelin and myelin basic protein (MBP) were regularly detected in r-EAE sera from day 21 post inoculation (p.i.), reaching maximum levels in the early chronic phase. IgG antibodies against galactocerebroside (GC) and galactose appeared in some r-EAE sera. Oligoclonal IgG bands were demonstrated in all r-EAE guinea pig sera 21-26 days p.i. The bands in serum decreased in number and strength in the chronic phase. They could be traced to antibodies against MT in 4 of 10 animals, but not to antibodies against myelin, MBP, GC or galactose. Oligoclonal IgG bands were also regularly visualized in r-EAE CNS 124 days p.i., suggesting persistent intrathecal IgG synthesis. They varied in number and migration between different regions of individual CNS. Oligoclonal CNS IgG was related to antibodies against MT in only one of 7 animals, and in no case to antibodies against myelin.

Animals↗
PubMed1984

Increased luminol enhanced chemiluminescence from peripheral granulocytes in juvenile periodontitis.

The granulocyte function in patients with juvenile periodontitis (JP) (eight men and six women, aged 13-33 yr) and sex and age matched controls was determined by the luminol enhanced chemiluminescence (CL) induced by opsonized and unopsonized bacteria or latex beads. Maximal CL induced by latex beads with or without autologus serum did not differ between the two groups. However, bacteria with or without autologous serum seemed to induce a higher maximal CL in the JP group. The difference was statistically significant for the results obtained with opsonized bacteria. Serum opsonized bacteria induced a much higher maximal CL than the unopsonized. The opsonin dependent reaction indicates a close association with the process of phagocytosis. The increased CL of granulocytes in JP could indicate the formation of extracellularly free oxygen radicals with the potential to damage tissue. These observations support a possible involvement of the granulocytes in the pathogenesis of JP.

Adolescent↗
PubMed1984

Analysis of alveolar ventilation in the newborn.

Twelve healthy term infants were examined at the median ages of 2 1/2 and 26 hours. Their alveolar ventilation, efficiency of ventilation, functional residual capacity, and lung nitrogen elimination patterns were studied by means of a computerised nitrogen wash out method. The results showed that alveolar ventilation and functional residual capacity increased over the period studied. At the same time effective dead space decreased leaving minute ventilation unchanged. Distribution of ventilation did not change.

Aging↗
PubMed1984

Calculation of lung volume in newborn infants by means of a computer-assisted nitrogen washout method.

A clinically adapted method for the calculation of the functional residual capacity in newborn infants has been developed. The method is based on a multiple breath nitrogen washout test, during which the ventilatory air flow and the nitrogen concentration signals are sampled by a minicomputer, which also performs the calculations. The ventilatory air flow is measured by a pneumotachometer connected to a face-out volume displacement body plethysmograph, and the nitrogen concentration by a nitrogen analyzer. The functional residual capacity volume is calculated from the sampled signals by adding the expired nitrogen volumes during each expiration, and finally dividing this sum by the initial alveolar nitrogen concentration. Before the calculations, the sampled signals are adjusted regarding nitrogen analyzer delay and plethysmograph characteristics. The method presented is designed to minimize the test equipment influence on the baby's respiration and also to inhibit the necessity of pneumotachometer compensations normally connected with washout methods. Furthermore, the calculated breath-by-breath values of end-expiratory nitrogen concentration, nitrogen volume, inspired and expired tidal volume, are stored on disk for further analysis and resimulation of the test. The method has been tested on a mechanical lung model and on washouts from healthy newborn infants. The model tests indicate that the accuracy and the reproducibility of the method are good, and the results from the infants are in good agreement with previously obtained results.

Computers↗
PubMed1984

Heart rate variability and electrocardiogram changes in the fetal lamb during hypoxia and beta-adrenoceptor stimulation.

Hypoxic changes in the ST waveform of the fetal electrocardiogram (FECG), with elevated T waves as the main response, have earlier been described in the fetal lamb as mediated via the beta-adrenoceptor cells, initiated by catecholamine release. A similar background to the increase in fetal heart rate variability (FHRV) during hypoxemia has been suggested. The aim of the present study was to elucidate this question and also to compare FHRV and changes in the ST waveform of the FECG as indicators of fetal distress. Twenty-six acutely exteriorized mature lamb fetuses were submitted to periods of graded hypoxemia. Fetal blood gases were measured and oxygen content was calculated. The FHRV was analyzed by a computer program and calculated as the differential index (DI) and the interval index (II). Eighty seconds of the recorded ECG coinciding in time with each fetal blood sample were analyzed using a PDP 11/40 minicomputer. The ECG signal was sampled at a rate of 1250 samples per second giving a resolution in time of 0.8 msec. Each QRS complex was detected with a semi-automatic program using a cross-correlation algorithm. QRS complexes that by the program were signalled to be doubtful were visually examined and either rejected or approved. Hence, the resulting list of R-R intervals was practically free from artefacts. From this list of R-R intervals the DI and II were computed according to YEH et al. [30]. Hypoxemia resulted in initially strongly increased DI from 3.1 +/- 2.5 to 17.7 +/- 13.8 (p less than 0.001) and in II from 1.88 +/- 0.65 to 3.77 +/- 2.06 (p less than 0.001) (Fig. 1). Obviously the change in oxygen content per se was strongly associated with the variability indices, as we found a strong correlation between delta oxygen content/min and delta DI/min (r = 0.81). In five fetuses the effect of prolonged hypoxemia on DI was studied (Fig. 2). After the initial rise from 1.6 +/- 1.1 to 31.2 /+- 9.0 (p less than 0.02) DI decreased to 19.4 +/- 20.7. A regression analysis showed a strong connection between DI and PaO2, (n = 93, T = - 5.34), whether there was no relation between DI and pH (T = - 1.85). There is strong evidence that hypoxemia and asphyxia induce an increase in the concentration of catecholamines in fetal blood [2, 23].(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1984

Does glucose administration affect the cerebral response to fetal asphyxia?

This study was designed to test whether the fetal brain has an increased resistance towards asphyxia at high levels of blood-glucose, compared with low levels. 35 fetal sheep were exteriorized and investigated under general anesthesia. Cerebral blood flow (CBF) was estimated with the 133Xenon-washout method. Cerebral uptake of oxygen, glucose, and lactate was measured. Somatosensory evoked potentials (SEP) were recorded. The fetuses were subjected to controlled asphyxia by ventilating the ewes with gas mixtures low in oxygen. The blood sugar levels of the fetuses were varied over a four-fold range. During normal oxygenation of the fetus variations in the blood glucose concentration induced considerable changes in the cerebral glucose uptake, whereas CBF and oxygen uptake were unaffected. During asphyxia, hyperglycemia was associated with rapid development of acidosis and reduction in cerebral oxygen consumption together with deterioration of the neurophysiological characteristics of the brain. Far from being beneficial during asphyxia, fetal hyperglycemia appeared to reduce the tolerance of the fetal brain towards asphyxia. This report together with other evidence provides support for the view that extra glucose might be disadvantageous for the asphyxiated fetus.

Animals↗
PubMed1984

Improved detection of oligoclonal IgG in cerebrospinal fluid by isoelectric focusing in agarose, double-antibody peroxidase labeling, and avidin-biotin amplification.

To demonstrate oligoclonal IgG bands (I) in unconcentrated cerebrospinal fluid, we used isoelectric focusing in agarose followed by protein transfer to cellulose nitrate membrane, double-antibody peroxidase labeling, and avidin-biotin amplification. I can be reliably seen after isoelectric focusing of 5-microL specimens containing 125 ng of IgG (25 mg/L). Thus the technique is more sensitive than others (e.g., silver staining) and more reliable than radioimmunofixation. When we used this technique with fluids from 62 patients with multiple sclerosis and infectious disease of the central nervous system, 84% displayed I, a percentage not increased when the same specimens were concentrated to 3.5 g of IgG per liter, examined by agarose isoelectric focusing, and stained with Coomassie Blue. Results for 53 patients with tension headache and psychoneurosis were all negative. By obviating the need to concentrate samples of cerebrospinal fluid the present method is a useful, sensitive alternative for demonstrating I.

Avidin↗
PubMed1983

Ia-expressing cells and T lymphocytes of different subsets in peripheral nerve tissue during experimental allergic neuritis in Lewis rats.

Inflammatory infiltrates in sciatic nerves during the acute phase of experimental allergic neuritis in the Lewis rat have been characterized with regard to occurrence and distribution of Ia-expressing cells and T-lymphocyte subsets by the help of an immunohistochemical double-staining technique, enabling the simultaneous visualization of T lymphocytes and Ia-expressing non-T cells. Large numbers of Ia-expressing irregular macrophage-like/dendritic cells were seen both within inflammatory infiltrates and within afflicted nervous tissue. Many W3/13-reactive T lymphocytes of both 'helper' and 'suppressor/cytoxic' phenotypes appeared in close contact with these Ia-expressing non-T cells, particularly within the infiltrates. B lymphocytes and plasma cells were relatively few and mainly found close to endoneurial vessels.

Animals↗
PubMed1983

Preservation of red blood cells: studies of erythrocyte adenine nucleotides using luminescence analysis.

The levels of ATP and total adenine nucleotides (ATP + ADP + AMP) were determined by firefly luciferase assay in red blood cells during storage for 5 weeks at 4 degrees C. With few exceptions, no significant differences in nucleotide levels were found between whole blood stored in CPD-adenine and various preparations of red blood cells in CPD-adenine or CPD with saline-adenine-glucose (SAG) as additive. The levels of ATP and total adenine nucleotides during storage are discussed in relation to glucose levels, extracellular pH and shelf life of the red blood cells.

Adenine Nucleotides↗
PubMed1983

Direct tissue isoelectric focusing of nervous system and muscle sections for detection of IgG patterns.

Agarose isoelectric focusing (IF) of 5-70 microns sections of frozen autopsy material (direct tissue IF; DTIF) from the central nervous system (CNS) and peripheral nervous system (PNS), and from muscle biopsy, followed by immunofixation with unlabeled or radiolabeled anti-serum against human gamma chains or IgG Fc fragments has been developed for analysis of IgG patterns. The DTIF technique followed by antiserum immunofixation is a promising tool for characterization of proteins in autopsy and biopsy materials from nervous and muscular systems. In multiple sclerosis brains, oligoclonal IgG bands were found which differed regarding number and mobility between the brains, and also between two different regions in single brains. For PNS, IgG patterns were easily detectable. In polymyositis muscle, no difference was found for IgG patterns when compared with normal muscle or serum.

Humans↗
PubMed1983

Leakage of adenylate kinase from stored blood cells.

The bioluminescent firefly luciferase assay for ATP was used to measure adenylate kinase activity in plasma. The formation of ATP from ADP was measured continuously in a coupled assay using a luminometer. Optimal analytical conditions were determined for the coupled reaction. The assay was used to follow accumulation of adenylate kinase in plasma of different preparations of stored red blood cells. Adenylate kinase was found to be released concomitantly with hemoglobin during aging. There was a high degree of correlation between the amount of accumulated hemoglobin and adenylate kinase. The assay was also used to measure lysis of stored platelets during aging.

Adenosine Diphosphate↗