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G Jansson

Publications and source records attributed to G Jansson.

At least 19 recordsLinked to original sources
PubMed1995

Anti-endomysium and anti-gliadin antibodies as serological markers for coeliac disease in childhood: a clinical study to develop a practical routine.

Anti-gliadin and anti-endomysium antibodies were analyzed in 174 children with suspected or verified coeliac disease with the aim of developing a practical routine. The biopsy was performed without knowledge of the antibody levels. To screen for coeliac disease is children younger than 2 years, we suggest the use of IgA anti-gliadin antibodies, giving a sensitivity of 100% and a specificity of 86%. In older children both tests should be used in parallel, i.e. a biopsy should be performed if at least one of the tests is positive, giving a sensitivity of 98% and a specificity of 81%. To avoid unnecessary biopsy before mucosal relapse can be demonstrated during gluten challenge in a child without clinical symptoms, we suggest that the tests are used as serial testing, i.e. a biopsy should be performed if both tests are positive.

Adolescent↗
PubMed1994

Serum food antibodies analyzed by enzyme-linked immunosorbent assay (ELISA) and diffusion-in-gel (DIG)-ELISA methods in children with and without celiac disease.

Serum antibodies IgA, IgG, and IgM against gliadin, ovalbumin, and beta-lactoglobulin were analyzed at the time of 228 small bowel biopsies in 116 celiac children. These were compared to the antibody levels at the time of biopsies performed in 199 children, where the biopsy discarded a clinical suspicion of celiac disease. For antibodies against gliadin, the enzyme-linked immunosorbent assay (ELISA) and diffusion-in-gel (DIG)-ELISA methods were compared. It was found that the combined information from IgA and IgG antigliadin antibodies gave the highest specificity (94%) and sensitivity (89%). The antibody responses to food antigens decreased with age in both celiac and reference children. The ELISA and DIG-ELISA methods gave comparable results and were equally efficient.

Adolescent↗
PubMed1993

Stimulating effects of mercuric- and silver ions on the superoxide anion production in human polymorphonuclear leukocytes.

In a survey of a number of heavy metal ions for effects on the oxidative metabolism (respiratory burst) of human polymorphonuclear leukocytes (neutrophils) we have found that mercury(II) and silver ions in micromolar concentration significantly increase the production of superoxide anions in cells, initiated by formyl-methionyl-leucylphenylalanine (fMLP). The stimulation of radical formation induced by a certain ion concentration varied considerably in cells isolated from different blood donors, from a moderate increase to a very large (up to 400% of control values). When the soluble stimulator phorbol myristate acetate (PMA) or the particulate stimulator Zymosan were used to initiate the cell respiratory burst, no additional stimulating effects by the metal ions on superoxide anion formation were observed. This fact might indicate that the effect of the metal ions on the fMLP-dependent initiation of cell activity is a mechanism coupled to the interaction between the chemotactic peptide and its corresponding receptor molecules on the cell surface. By increasing the concentration of silver ions during pre-incubation of resting neutrophils, a spontaneous activation of the cells could be recorded at a concentration exceeding 5 microM. However, the silver ion concentration at which such spontaneous initiation of the respiratory burst occurred varied significantly between blood samples from different donors with a concentration range of 5 to 15 microM. This effect could not be shown for mercuric ions due to the toxicity of the metal above 5 microM. Blood samples from some donors contained neutrophils that could be activated by either mercuric- or silver ions at concentration as low at 1 microM. The spontaneous activation of neutrophils with elevated concentrations of silver ions is kinetically similar to the PMA-induced. The onset of superoxide anion formation is preceded by a lag period whose length varies in time with the concentration of agent applied to the cells. It is a known fact that once the neutrophils have been activated with fMLP it is not possible to reactivate the cells by a second supplementation of fMLP. However, after cessation of the fMLP-induced activation, addition of PMA or silver ions gives rise to renewed production of superoxide anions. We propose two different mechanisms of action of silver ions on oxidative metabolism of neutrophils.(ABSTRACT TRUNCATED AT 400 WORDS)

Anions↗
PubMed1991

Oestrogen-induced enhancement of myeloperoxidase activity in human polymorphonuclear leukocytes--a possible cause of oxidative stress in inflammatory cells.

Micromolar concentrations of beta-estradiol, estrone, 16-alpha-hydroxyestrone and estriol enhance the oxidative metabolism of activated human PMNL's. The corresponding 2-hydroxylated estrogens 2-OH-estradiol, 2-OH-estrone and 2-OH-estriol act on the contrary as powerful inhibitors of cell activity. Equilenine, a naturally occurring steroid hormone structurally closely related to estrone, removes the estrogen-induced increase in oxidative metabolism of activated PMNL's without diminishing cell activity determined in the absence of enhancing hormone. A number of other female and male sexual hormones were without potentiating effect. The cell response to hormone treatment was assayed as increase (or decrease) in LU-dependent CL of activated PMNL's. When assaying LUC-dependent CL of the cells no stimulatory effects of the estrogens could be detected. This fact may imply that the myeloperoxidase enzyme system of the cells is the target for the hormonal action. Various inhibition experiments using activated PMNL's or purified MPO confirmed this conclusion. The efficicious hormones induced approximately a doubling of CL of activated cells and a tenfold increase of the activity of purified MPO. If cell activity was initiated by the additions of low concentrations of hydrogen peroxide, the presence of estrogens caused a remarkable enhancement of the luminol-dependent chemiluminescence. PMNL's activated with fMLP release MPO activity into the surrounding cell medium. It has been found here that the presence of estrogens in micromolar concentrations greatly increases such enzyme release. Release of MPO activity from the cells could be achieved by the mere addition of estrogenic hormones. Estrogen-induced release of enzyme activity was abrogated by the simultaneous presence of equilenine in the cell suspension. Released enzyme responded vigorously to estrogens in the presence of chloride ions and its substrate, hydrogen peroxide. About a tenfold increase in enzyme activity could be measured in the presence of 5 microM beta-estradiol or esteriol. The activity of the released enzyme (as well of purified MPO) was effectively inhibited by small amounts of anti-MPO antibodies. This observation together with other inhibition experiments was taken as evidence for the view that the released enzyme was identical with myeloperoxidase.

Equilenin↗
PubMed1989

Intestinal permeability to inert sugars and different-sized polyethyleneglycols in children with celiac disease.

Intestinal permeability was measured in a total of 42 children, 29 of whom had celiac disease. The celiac children were studied at presentation, during gluten-free diet, and/or at gluten challenge. The permeability was assessed by oral lactulose/L-rhamnose in all 42 children and also by different-sized polyethylene glycols (PEG) in 36 children. Results were compared with the findings of small intestinal biopsy. The mean of the permeability tests in children with enteropathy was significantly abnormal compared with the result in children with a normal mucosal morphology. The lactulose/L-rhamnose test and the PEG test gave equivalent results in the same child. In the celiac children abnormal permeability properties at presentation normalized during gluten-free diet and reappeared during gluten challenge. It is concluded that measurement of intestinal permeability may be a valuable tool in monitoring children with celiac disease, preferably when serial measurements are available in the same child.

Adolescent↗
PubMed1989

Intestinal permeability assessed with different-sized polyethylene glycols in children undergoing small-intestinal biopsy for suspected celiac disease.

The gastrointestinal permeability was assessed by means of an oral load of a mixture of different-sized polyethylene glycols (PEG 400 and PEG 1000) in 76 children undergoing small-intestinal biopsy because of suspected celiac disease. Children with a mucosal abnormality suggestive of celiac disease had a lower urinary recovery of larger PEG molecules. They also displayed an altered permeability barrier, as evidenced by a lower ratio of recovery between large (1074 Da) and small (370 Da) PEG molecules. Gluten elimination and gluten challenge caused a significant change in PEG recoveries in children undergoing repeated PEG tests. Repeated assessments of intestinal permeability by means of different-sized PEGs after gluten withdrawal and challenge could complement or indicate suitable time for performing small-intestinal biopsy in children with gluten intolerance.

Adolescent↗
PubMed1986

Coeliac disease in children of short stature without gastrointestinal symptoms.

Eighty-seven children with short stature (height more than 2 SD below the mean for age and sex) were investigated by small intestinal biopsy. There was no obvious reason for their growth retardation found by routine examination and they had no gastrointestinal symptoms. Coeliac disease was found in two children and probable coeliac disease in two children. Although the prevalence of coeliac disease was comparatively low in this study of Swedish children with short stature, it emphasizes the fact that coeliac disease must be considered in a child with short stature even in the absence of gastrointestinal symptoms.

Adolescent↗
PubMed1985

Formation of antibodies to native DNA in rats after administration of native DNA treated with the xanthine-xanthine oxidase system.

The injection of native (double-stranded) deoxyribonucleic acid treated with the xanthine-xanthine oxidase system and emulsified with complete Freund's adjuvant into rats over a prolonged period of time induces the formation of antibodies to double-stranded DNA. The titer of antibodies was determined by an enzyme-linked immunosorbent assay (ELISA) in sera from treated animals. Control experiments using untreated native DNA or phosphate buffered saline likewise emulsified with Freund's Adjuvant showed only insignificant increases in titers of the antibody.

Animals↗
PubMed1984

Long-term follow-up of infants under intensive care with tracheotomy during the period 1956-1965.

Twenty-seven infants who survived intensive care during early infancy in the pioneering period of neonatal intensive care (1956-1965) were investigated after 8-17 years. The selection criterion was maintenance of a tracheotomy for more than 15 days during the first 12 months of life. A variety of clinical, physiological, radiological and psychiatric sequelae was found. Respiratory symptoms were the dominating problem during the post-tracheotomy period. The long-term follow-up revealed that these symptoms had a strong tendency to subside. At the time of the follow-up, as many as 20 children (74%) did not experience any functional impairment.

Child Development↗
PubMed1983

Similar prevalence of coeliac disease in children and middle-aged adults in a district of Sweden.

Coeliac disease in children and adults is considered to be a variety of the same disorder. This gains epidemiological support in the present study, which reports on the observed prevalence of coeliac disease in an area of Sweden (population, 140 500). On 1 July 1981, the prevalence rate was found to be 104/100 000 (1:960) among children, and the same figure, 106/00 000 (1:950), was found for coeliac disease unaccompanied by dermatitis herpetiformis in the middle-aged population. The figures were obtained in patients seeking medical are and thus represent minimum rates, and it is likely that the actual prevalence of coeliac disease in Sweden will prove still higher.

Adolescent↗
PubMed1983

Tactile guidance of movement.

In some prototype mobility aids for the blind information about the environment is obtained with the aid of patterns within a matrix of tactile point stimuli. The aim of this report is to summarize some experiments on the possibilities of guiding movements in 3-D space by devices of this kind, the movements studied being: (1) batting a ball, (2) walking and pointing to a target, and (3) slalom walking. The results were that movements could be guided by such a matrix with reasonable precision and time consumption. There are many remaining problems, especially in a cluttered environment, but they can be expected to be decreased if we are able to increase our knowledge about how touch, or rather the haptic system, is functioning, and if we can utilize this knowledge in constructing more effective tactile displays.

Blindness↗
PubMed1980

Event perception.

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Blindness↗
PubMed1979

Muscle abnormalities in coeliac disease: studies on gross motor development and muscle fibre composition, size and metabolic substrates.

In 11 children with coeliac disease gross motor development was assessed before and during diet treatment using the gross motor subscale of the Denver developmental screening test. ATP, creatine phosphate (CP), glycogen and lactate concentrations, muscle fibre size and fibre composition were measured in specimens obtained by needle biopsy from the vastus lateralis muscle. Before treatment, gross motor development was delayed. ATP, and to a lesser extent, CP and glycogen concentrations were lowered compared to a control group. After treatment, gross motor development was normal and no differences in ATP, CP or glycogen concentrations were found compared to the control group. Fibre size seemed unaffected by the disease. The percentage of type 1 fibres was significantly lower before treatment, compared to values obtained during treatment and from the control group. Whether these metabolic changes were due to the coeliac disease per se or the inactivity which it causes was not possible to establish. In humans, only altered neurogenic influence on the muscles has been previously shown to give changes in fibre composition.

Adenosine Triphosphate↗