Biomedical subjects

M Gunnarsson

Publications and source records attributed to M Gunnarsson.

At least 19 recordsLinked to original sources

PubMed2004

Neurofilament and glial fibrillary acidic protein in multiple sclerosis.

OBJECTIVE: To evaluate levels of neurofilament light (NFL) and glial fibrillary acidic protein (GFAP) in CSF from patients with multiple sclerosis (MS) in relation to clinical progress of the disease. METHODS: CSF levels of NFL and GFAP were determined by sensitive ELISAs in 99 patients with different subtypes of MS, classified in terms of "ongoing relapse" or "clinically stable disease," and 25 control subjects. Levels were compared with paraclinical data such as immunoglobulin G index and inflammatory cell count in the CSF, and the levels were related to Expanded Disability Status Scale score and progression index at clinical follow-up evaluations later in the disease course. RESULTS: NFL and GFAP levels were elevated in MS patients as compared with control subjects (p < 0.001). The NFL levels were higher at relapses, whereas GFAP levels were unaffected. High NFL levels correlated with progression in patients with an active relapse (r = 0.49; p < 0.01) and in clinically stable patients (r = 0.29; p < 0.05). GFAP correlated to progression in the total patient cohort (r = 0.24; p < 0.05). Moreover, a strong correlation between NFL levels and inflammatory cell counts was evident in the group of patients with an ongoing relapse (r = 0.52; p = 0.001). CONCLUSIONS: CSF levels of neurofilament light and glial fibrillary acidic protein may have prognostic value in multiple sclerosis.

Adult↗

PubMed2003

Native and transformed alpha2-macroglobulin in plasma from patients with multiple sclerosis.

Multiple sclerosis (MS) is an inflammatory demyelinating disease with unknown etiology. Various proteinases have been observed in increased levels in the central nervous system of patients with MS, which may contribute to the release of immunogenic myelin components. alpha2-Macroglobulin (alpha2M) inhibits a broad spectrum of proteinases sterically, undergoing major conformational changes induced by the proteinases themselves. Moreover, alpha2M acts as a carrier of several cytokines in the systemic circulation. By use of radial immunodiffusion, we determined the total alpha2M levels in plasma from 28 MS patients and 15 control subjects [14 patients with other neurologic diseases (OND) and one healthy individual]. No significant differences in total alpha2M concentration were observed between the MS patients and the control subjects. A comparison of the degree of alpha2M transformation in MS patients with different disease courses and controls was performed, using monoclonal antibodies (mAbs) specific for binding to native and transformed alpha2M, respectively. The fractions of transformed alpha2M were significantly increased in patients with secondary or primary progressive disease course compared with the controls. No significant differences were obtained using a native-specific mAb. At least a major proportion of alpha2M from the MS patients was able to change conformation from its native to its transformed state, as demonstrated by a shift in mAb reactivity, following methylamine treatment of the plasma samples. In conclusion, the results indicate that plasma alpha2M may be inactivated at a higher degree in patients with chronic progressive MS compared with patients with OND. This may influence the levels of proteinases and cytokines in the systemic circulation and may furthermore have diagnostic implications.

Adult↗

PubMed2002

No radiation protection reasons for restrictions on 14C urea breath tests in children.

Traditional (14)C urea breath tests are normally not used for younger children because the radiation exposure is unknown. High sensitivity accelerator mass spectrometry and an ultra-low amount (440 Bq) of (14)C urea were therefore used both to diagnose Helicobacter pylori (HP) infection in seven children, aged 3-6 years, and to make radiation dose estimates. The activity used was 125 times lower than the amount normally used for older children and 250 times lower than that used for adults. Results were compared with previously reported biokinetic and dosimetric data for adults and older children aged 7-14 years. (14)C activity concentrations in urine and exhaled air per unit administered activity for younger children (3-6 years) correspond well with those for older children (7-14 years). For a child aged 3-6 years who is HP negative, the urinary bladder wall receives the highest absorbed dose, 0.3 mGy MBq(-1). The effective dose is 0.1 mSv MBq(-1) for the 3-year-old child and 0.07 mSv MBq(-1) for the 6-year-old child. For two children, the 10 min and 20 min post-(14)C administration samples of exhaled air showed a significantly higher amount of (14)C activity than for the rest of the children, that is 6% and 19% of administered activity exhaled per hour compared with 0.3-0.9% (mean 0.5%) of administered activity exhaled per hour indicating that these two children that is were HP positive. For a 3-year-old HP positive child, absorbed dose to the urinary bladder wall was 0.3 mGy MBq(-1) and effective dose per unit of administered activity was 0.4 mSv MBq(-1). Using 55 kBq, which is a normal amount for older children when liquid scintillation counters are used for measurement, the effective dose will be approximately 6 micro Sv to a 3-year-old HP negative child and 20 microSv to a HP positive child. Thus there is no reason for restrictions on performing a normal (14)C urea breath test, even on young children.

Adolescent↗

PubMed2001

Conformational state and receptor recognition of the C-terminal domain of human alpha(2)-macroglobulin after dissociation into half-molecules.

BACKGROUND: Dissociation of native human alpha(2)-macroglobulin (alpha(2)M) by sodium thiocyanate generates stable half-molecules with intact thiol esters. Significant conformational changes occur by the dissociation, which are similar to those occurring by transformation from native to methylamine-treated alpha(2)-macroglobulin. METHODS: The conformational state of the receptor-binding domain of the half-molecules was investigated by receptor binding and clearance studies, and by use of a panel of 11 monoclonal antibodies (mAbs) specific for the 18-kDa C-terminal receptor-binding fragment of alpha(2)-macroglobulin. RESULTS: The half-molecules simultaneously express epitopes specific for native, as well as epitopes specific for transformed alpha(2)-macroglobulin. While it is possible to immunochemically discriminate between the different forms of tetrameric protein, the half-molecules retain a conformational state with no observed conformational changes in the C-terminal domain following cleavage of thiol esters or bait regions. The in vivo clearance rate in mice was consequently significantly slower for the half-molecules than for the tetrameric receptor-recognized forms of alpha(2)-macroglobulin. Furthermore, half-molecules demonstrate lower affinity for binding to mouse macrophages than methylamine-treated tetrameric alpha(2)-macroglobulin in competition studies. CONCLUSIONS: It is suggested that contact zones are functionally important for mediating conformational switches, which result in trapping and exposure of the receptor-binding sites.

Animals↗

PubMed2000

Sorption Studies of Cobalt(II) on Colloidal Hematite Using Potentiometry and Radioactive Tracer Technique.

The sorption of Co(II) on colloidal hematite was studied as a function of pH, ionic strength, and Co(II) concentration. Two different techniques were used, yielding two different sets of information: (i) potentiometric titrations that provide information on the number of protons released as a function of pH owing to the sorption of Co(II) and (ii) measurement of the amount of cobalt sorbed on the surface as a function of pH using a radioactive tracer, (60)Co. At low Co(II) concentrations (10(-8) M), the sorption was found to be independent of ionic strength but there seems to be a weak ionic strength dependence at higher Co(II) concentrations (10(-4) M). The adsorption edge moved to higher pH with increasing Co(II) concentration. For the high Co(II) concentration, the number of protons released per cobalt sorbed increased from zero to approximately 1.5. The basic charging properties of hematite were modeled with four different surface complexation models. The 1-pK Basic Stern Model (BSM), with binding of electrolyte ions to the Stern plane, seems to be the most reasonable model if the ambition is to describe experimental data at different ionic strengths. The sorption of cobalt was modeled with the 1-pK BSM. By introducing a low concentration of high affinity surface sites for cobalt sorption it was possible to model the sorption in very wide cobalt concentrations, ranging from 10(-8) M to 10(-4) M. Copyright 2000 Academic Press.

Journal Article↗

PubMed2000

Aberrant forms of alpha(2)-macroglobulin purified from patients with multiple sclerosis.

The biochemical properties of alpha(2)-macroglobulin were investigated in four patients with multiple sclerosis and compared to alpha(2)-macroglobulin from healthy controls. An impaired stability of alpha(2)-macroglobulin from the multiple sclerosis patients was demonstrated as a spontaneous conversion to an electrophoretic"fast" form of alpha(2)-macroglobulin upon purification and storage, with a concomitant decrease in functional capacity to inhibit proteinases. The ability to form complexes with proteinases was significantly reduced in alpha(2)-macroglobulin purified from the multiple sclerosis patients. The aberrant molecular arrangements of the protein were not due to proteinase cleavages in the bait regions of alpha(2)-macroglobulin, as demonstrated by gel electrophoresis and protein sequencing. The number of functional thiol esters, however, was reduced in alpha(2)-macroglobulin purified from the multiple sclerosis patients, an observation compatible with the impaired proteinase binding property. Furthermore, differences in isoelectric points were observed between alpha(2)-macroglobulin from the multiple sclerosis patients and alpha(2)-macroglobulin from healthy controls. The results suggest that aberrant forms of alpha(2)-macroglobulin may be present in patients with multiple sclerosis.

Adult↗

PubMed2000

Decreased stability of alpha2-macroglobulin purified from patients with multiple sclerosis.

OBJECTIVES: To investigate conformational properties of alpha2-macroglobulin from multiple sclerosis patients. MATERIALS AND METHODS: alpha2-macroglobulin was purified to homogeneity from plasma of 4 multiple sclerosis patients and 5 healthy controls. The plasma and the purified alpha2-macroglobulin from each individual were investigated using polyacrylamide gel electrophoresis. RESULTS: Impaired stability of purified alpha2-macroglobulins from multiple sclerosis patients was demonstrated with spontaneous conversion to an electrophoretic "fast" form upon purification and following storage not ascribable to bait region cleavage. CONCLUSION: alpha2-macroglobulin from multiple sclerosis patients displays altered stability. Possible functional impairments of proteinase inhibition mechanisms are discussed.

Adult↗

PubMed2000

Immunochemical aberrations of alpha2-macroglobulin purified from a patient with multiple sclerosis.

We report on a patient with primary progressive multiple sclerosis who was found to present alpha2-macroglobulin with aberrant immunochemical properties. alpha2-macroglobulin was purified from plasma and investigated in ELISA using highly conformation specific monoclonal antibodies. The purified alpha2-macroglobulin displayed reactivity with antibodies specific for binding to native alpha2-macroglobulin as well as with antibodies specific for binding to transformed alpha2-macroglobulin. Furthermore, following methylamine treatment, alpha2-macroglobulin from the multiple sclerosis patient presented a reduced shift in antibody reactivity from the native-specific to the transformed-specific antibodies, as compared to normal alpha2-macroglobulin. In conclusion, the results suggest that alpha2-macroglobulin from this multiple sclerosis patient presents conformational aberrations, which may have implications on the capacity to eliminate proteinases from the systemic circulation.

Adult↗

PubMed2000

Conformational variants of human alpha2-macroglobulin are reflected in a C-terminal 'switch region'.

Human alpha2-macroglobulin displays extensive conformational changes when induced to transform into new quaternary structures, which are eliminated from the systemic circulation by receptor-mediated endocytosis. One major region involved in these conformational changes is located in a segment of 30 amino acids from Glu1314 to Ser1343 (-Glu-Glu-Phe-Pro-Phe-Ala-Leu-Gly-Val-Gln-Thr-Leu-Pro-Gln-Thr-Cys-Asp -Glu-Pro-Lys-Ala-His-Thr-Ser-Phe-Gln-Ile-Ser-Leu-Ser-), which we term the 'switch region' of alpha2-macroglobulin, as deduced by immunochemical techniques. Monoclonal antibodies were generated using either native, methylamine-treated or the 18-kDa C-terminal receptor-binding fragment as the immunogen. From an extensive number of obtained hybridomas, 11 mAbs were selected because of their capacity to bind to the C-terminal fragment. Irrespective of the original configuration of the antigen used for immunization, seven of the antibodies were shown to be reactive with a set of overlapping epitopes, closely positioned within the 'switch region', as confirmed by the use of synthetic peptides covering the entire C-terminal fragment. The specificities of the seven individual antibodies, as determined by ELISA and BIAcore technologies, revealed a pronounced conformational pleomorphism in the 'switch region'. The results indicate that the 'switch region' may be involved in the exposure of the receptor recognition site and can be used as an indicator region for different conformational states of alpha2-macroglobulin.

Amino Acid Sequence↗

PubMed2000

Effects of inhalation of corticosteroids immediately after experimental chlorine gas lung injury.

BACKGROUND: To assess the effects of treatment with nebulized corticosteroids immediately after chlorine gas injury. METHODS: Eighteen anesthetized and mechanically ventilated pigs were exposed to chlorine gas (140 ppm for 10 minutes) and observed for 6 hours. Nine pigs were treated with nebulized beclomethasone-dipropionate 20 microg/kg (BDP group), and nine pigs were given no treatment (control group). RESULTS: All animals developed severe pulmonary dysfunction. The initial decrease in PaO2 was similar in both groups, but BDP-treated animals improved whereas control animals deteriorated (p < 0.005; analysis of variance). Pulmonary vascular resistance increased in both groups but less in the BDP group (p < 0.01). Lung-thorax compliance was better preserved in the BDP group (p < 0.01), and oxygen delivery was significantly better in the BDP group (p < 0.01). One animal died in the BDP group, as did three animals in the control group. CONCLUSION: Immediate treatment with nebulized BDP improved pulmonary and cardiovascular function after experimental chlorine gas injury.

Administration, Inhalation↗

PubMed2000

Fewer problems with dry nasal mucous membranes following local use of sesame oil.

Many people experience problems with a dry nasal mucous membrane, often without wondering why. Their noses itch and burn and dried mucus collects there. These problems are exacerbated during the winter, in air-conditioned environments and after nasal irradiation. Twenty patients experiencing problems with dryness of the nose were selected from outpatient clinics, together with twenty patients who had previously undergone nasal irradiation. During the first five days no treatment was administered. For the following twenty days the patients sprayed sesame oil into each nostril three times a day. For the last five days no treatment was given. When both groups received treatment and sprayed sesame oil (Nozoil) in their noses, the nasal problems decreased significantly. The greatest effect is exerted on dryness. The side effects from using this oil are few in number and mild.

Administration, Intranasal↗

PubMed1999

Cortical magnetic stimulation in patients with genuine stress incontinence: correlation with results of pelvic floor exercises.

Pelvic floor training is an established conservative method of treatment in patients with genuine stress incontinence. It is not known why only a proportion of patients benefit from this form of treatment, while others with a comparable degree of incontinence do not. Since muscle awareness is of vital importance in pelvic floor training, we decided to investigate whether differences in outcome might be explained by differences in cortical control of the pelvic floor muscles. The function in the total motor pathway to the pelvic floor muscles was examined with cortical magnetic stimulation and circumvaginal EMG recording. Since lesions of the peripheral motor pathway have been demonstrated in patients with genuine stress incontinence, possible differences at this level were investigated by means of terminal pudendal motor latencies, using electrical nerve stimulation and anal recording EMG. We found that patients who succeeded with pelvic floor exercises for genuine stress incontinence had a significantly higher probability of response to cortical magnetic stimulation and significantly larger response amplitudes than the patients who did not benefit from training. The findings in the latter group did not differ from those of a healthy control group. No differences between the groups were found in the terminal pudendal motor latencies. We conclude that women with genuine stress urinary incontinence, successfully alleviated by a physiotherapeutic training program, have a higher degree of corticofugal control of their perineal muscles than women who do not succeed with the same treatment program and healthy controls. Neurourol. Urodynam. 18:437-445, 1999.

Adult↗

PubMed1999

Female stress, urge, and mixed urinary incontinence are associated with a chronic and progressive pelvic floor/vaginal neuromuscular disorder: An investigation of 317 healthy and incontinent women using vaginal surface electromyography.

Reduction of the maximum vaginal surface electromyography (EMG) activity has previously been demonstrated in women with stress, urge, and mixed incontinence in comparison with healthy volunteers [Gunnarsson and Mattiasson, Scand J Urol Nephol 157:89-95, 1994]. The present study was performed to investigate if these EMG changes are age dependent and whether healthy parous women in general might show an age-related decrease of vaginal and pelvic neuromuscular activity. A total of 317 women, 144 with urinary incontinence and 173 healthy volunteers, 20 to 76 years of age, were investigated. The maximum EMG activity during repeated short contractions (2 s) was measured. We found that parous women who have maintained continence through the years had a normal pelvic floor function as estimated with vaginal surface EMG. In contrast, all three groups of incontinent women showed a successive decrease of the EMG activity with increasing age. This difference was highly significant (P < 0.001) in women above the age of 50. No significant differences could be seen between groups when stress, urge, and mixed incontinent women were compared. Even though any convincing correlation between the amount of urinary leakage and the reduction of EMG activity was not found, we conclude that a chronic and progressive deterioration of the pelvic-vaginal neuromuscular function occurs in women who develop urinary incontinence. The results support the view that a common pathophysiological mechanism in patients with stress, urge, and mixed incontinence might exist. The findings might help to establish a new perspective for the understanding of the pathophysiology, diagnosis, treatment, and prevention of female incontinence. Neurourol. Urodynam. 18:613-621, 1999.

Adult↗

PubMed1999

Tolerance induction using the Malmö treatment model 1982-1995.

The ultimate goal in the treatment of haemophilia patients with inhibitors is to eradicate permanently the inhibitor and induce tolerance. Here we summarize our experience at the Malmö centre regarding tolerance induction according to the Malmö Treatment Model. The protocol includes immunoadsorption if needed, neutralization of inhibitor and replacement with factor concentrates, cyclophosphamide intravenously for 2 days (12-15 mg kg-1 bw) and then orally (2-3 mg kg-1 bw) for an additional 8-10 days and intravenous gammaglobulin daily at dosages of 0.4 g kg-1 bw for 5 days. This protocol has been applied in 23 haemophilia patients with inhibitors, 16 haemophilia A patients and seven haemophilia B patients. Altogether 36 attempts have been made to induce tolerance. Ten of the 16 haemophilia A (62.5%) and 6/7 patients with haemophilia B (86%) became tolerant after the treatment. The chances of success or failure are roughly equal, if the series is considered in a historical perspective. The data showed that the chances of success in tolerance induction with the Malmö protocol were best in those patients with low inhibitor titres, with relatively low historical inhibitory peak and with a long interval since the previous replacement therapy. This was especially true where no inflammatory state was present at the start or during tolerance induction. The advantage with this method compared to the high-dose regimen is that in the successful cases tolerance can be achieved within 3-4 weeks.

Adolescent↗

PubMed1999

Factors of the plasminogen activator system in human testis, as demonstrated by in-situ hybridization and immunohistochemistry.

A growing body of evidence suggests that the plasminogen activator (PA) system is crucially involved in reproductive physiology in both sexes. Certain factors of the PA system have been found to be present in organs of the male reproductive tract in various species, and the presence of several of the factors was recently demonstrated in monkey testis. The present morphological study was therefore designed to investigate the occurrence and distribution of the tissue and urokinase plasminogen activators (t-PA and u-PA), the u-PA receptor (u-PAR) and the plasminogen activator inhibitors (PAI-1 and PAI-2) in normal human testis. Intraoperative specimens from seven patients undergoing orchidectomy or testicular biopsy were studied using in-situ hybridization (ISH) and immunohistochemistry (IHC). All five factors studied could be detected with both the ISH and IHC procedures. The ISH signals were localized to sites in the testicular tubules in a stage-specific manner. There was good correlation between results obtained with the two methods, though in IHC the tubules were stained more uniformly. The findings provide support for the involvement of the PA system in human male reproductive physiology.

Animals↗

PubMed1999

Local corticosteroid treatment of caustic injuries of the esophagus. A preliminary report.

So far, no therapy has been shown to reduce the incidence of strictures in the esophagus after ingestion of caustic agents. Two patients with pronounced caustic ingestion injuries were treated locally with solutions of corticosteroids normally used for inhalation therapy in lung diseases. Serious strictures did not appear, and their swallowing returned to normal. Further studies are needed.

Administration, Topical↗

PubMed1998

Binding of soluble myelin basic protein to various conformational forms of alpha2-macroglobulin.

Myelin basic protein is known to be released into the circulation following traumatic injuries or demyelination within the central nervous system, resulting in the generation of potentially immunogenic myelin basic protein material. In this investigation we have studied the binding of bovine and human myelin basic protein to human alpha2-macroglobulin, which was found to be the only major myelin basic protein-binding protein in human plasma. Myelin basic protein bound to all three conformational forms of alpha2-macroglobulin studied, i.e., native alpha2-macroglobulin, methylamine-treated alpha2-macroglobulin, and chymotrypsin-treated alpha2-macroglobulin. Zinc chloride (1 mM) or 1 mM iodoacetamide partly blocked the complex formation between myelin basic protein and alpha2-macroglobulin, while 1 mM magnesium chloride, 1 mM calcium chloride, or 1 mM EDTA had no effect on binding. Chymotrypsin and trypsin can degrade myelin basic protein to fragments which do not bind to alpha2-macroglobulin. However, when myelin basic protein was complexed with any of the conformational forms of alpha2-macroglobulin, no significant release of Na[125I]-labeled myelin basic protein occurred after proteinase treatment. The results suggest that binding of myelin basic protein to alpha2-macroglobulin may protect extracellular compartments in vivo from immunogenic myelin basic protein fragments and alpha2-macroglobulin may participate in the specific clearance of myelin basic protein from the circulation.

Blood Proteins↗

PubMed1998

Immunoadsorption for removal of inhibitors: update on treatments in Malmö-Lund between 1980 and 1995.

Treatment of severe bleeding and the performance of surgery in haemophilia patients with inhibitors creates severe problems. It is generally agreed that treatment is most effective if circulating levels of factor VIII/IX can be achieved long enough for control of haemostasis. Immunoadsorption with protein A for the removal of inhibitor has improved treatment for patients with initial inhibitor titres too high to neutralize by infusion alone. This is a summary of our experience in Malmö regarding immunoadsorption and haemostasis. A total of 19 applications with immunoadsorption in 10 patients were performed. On all occasions it was possible to eliminate totally the inhibitor or reduce it to low levels that could easily be neutralized with factor concentrate. Haemostatic levels of coagulation factors could be maintained for 5-9 days in all but one patient. This period was sufficient to stop ongoing haemorrhage or prevent excessive bleeding at surgical interventions.

Factor IX↗