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Biomedical subjects

E Jansson

Publications and source records attributed to E Jansson.

At least 181 records · Page 10Linked to original sources
PubMed1978

Electron probe X-ray microanalysis of human muscle biopsies.

The elemental composition of human muscle fibres have been determined by electron probe microanalysis. In order to distinguish between different types of fibres, two approaches were used. In one approach individual fibres were isolated, portions of them used for a typing by histochemical methods and the main part used for X-ray microanalysis. In the other approach the muscle biopsy was serial-sectioned, some sections used for a histochemical typing and the others (16 micrometer thick cryosections) used for X-ray microanalysis in th eelectron microscopy. The comparison of the ratios between P, S and K in Study No. 1 and 2 indicates different concentrations of sulphur in the subsarcolemmal zone and in the interior of the fibre. Both routes give information on all elements (except the ten lightest ones) contained in the fibres or in sections of them, provided the concentration is high enough. In order to obtain quantitative data, expressed as mmol/kgw, the spectra of the specimens were compared to those of standards of known composition and the data subjected to a so called ZAF-correction (corrections for the atomic number effect, absorption of X-rays in the specimen and secondary fluorescence). Quantitative data concerning phosphorus, sulphur, chlorine and potassium were obtained in Study No. 2. A significantly higher sulphur concentration was found in type IIA muscle fibres as compared to those of type I.

Chlorine↗
PubMed1978

Studies in sarcoidosis: intradermal Mycoplasma test.

Mycoplasma strain 215-M, closely related to Mycoplasma orale type 1, was grown in human macrophage monolayers in vitro. Sonicated homogenates of macrophages diluted in saline solution were used for intradermal skin tests in 19 patients with sarcoidosis and in 25 patients with a variety of other diseases. Positive skin-test reactions to this newly developed Mycoplasma test material were observed significantly more often in the patients with sarcoidosis than in the other patients.

Adult↗
PubMed1978

Cross-sectional area of the thigh muscle in man measured by computed tomography.

Nine subjects with different training background were studied by means of muscle biopsy from musculus vastus lateralis. The cross-cut area of the different muscle fibre types was measured. By the use of a soft tissue X-ray technique, computed tomography, a cross-sectional picture of the thigh was produced at the same level as the biopsy was taken. The total cross-cut area of the vastus lateralis muscle was measured from this picture. This technique to measure a cross-cut muscle area from an X-ray picture was evaluated and found to be accurate and reproducible. The mean fibre area was highly correlated (r = 0.91; P less than 0.001) to the cross-cut area of the vastus lateralis muscle. The total number of fibres in the vastus lateralis muscle was estimated. It was concluded that the cross-sectional area of the thigh muscle can be accurately determined by means of computed tomography. The larger cross-sectional area of the vastus lateralis muscle in well trained subjects was primarily explained by a larger cross-sectional area of the fibre, while the total number of fibres in the vastus lateralis muscle seemed to be fairly equal among the subjects.

Adipose Tissue↗
PubMed1977

Muscle adaptation to extreme endurance training in man.

To evaluate the effect of extreme endurance training on muscle fibre composition and activities of oxidative enzymes in different fibre types biopsies were taken from vastus lateralis, gastrocnemius and deltoideus of elite orienteers. Comparisons were made between the (trained) leg muscles and the (relatively untrained) arm muscles, and with leg muscles of 16--18 years old boys. The orienteers had the same percentage type I fibres and vastus lateralis and gastrocnemius as in deltoideus, but higher percentage type I fibres in vastus lateralis compared with the controls. The similarity between trained and untrained muscle in the orienteers suggests that training had not caused the high percentage type I fibres which rather might be the result of selection of individuals with the best prerequisites for high oxidative capacity. However, the distribution of type II subgroups in the leg muscles of the orienteers differed from both their own deltoideus and leg muscles of the controls, the relationship IIA/IIB being altered in favour of the more oxidative IIA. The leg muscles of the orienteers also showed an increased occurrence of the normally IIC fibre. These latter findings point at the possibility of a training induced alteration in the subgroup pattern. Unlike in the controls there was no significant difference in succinate dehydrogenase activity, measured in single fibres, between type I and II fibres in gastrocnemius of the orienteers. Thus, type II fibres have the ability metabolically to adapt to high oxidative demands. This might to some extent be mediated by a conversion from IIB to IIA form.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed1977

Fiber types and metabolic potentials of skeletal muscles in sedentary man and endurance runners.

This description of some of the present knowledge on skeletal muscle fibers, their metabolic potentials, and their interplay with the degree of physical activity has revealed that skeletal muscle of man has a very large capacity for adaptation. Moreover, this adaptability appears to be of utmost importance for the metabolic response as well as for performance. Although all this is true, it should not distract us from the fact that we are lacking the most important information. The questions that need to be answered are: What triggers the changes to take place? Which are the regulatory mechanisms?

Adaptation, Physiological↗
PubMed1977

Isolation of a mycoplasma from three patients with lepromatous leprosy.

Using a modified cell-free culture medium and modern microscopic equipment, a mycoplasma was isolated from scrapings of skin lesions of three patients with lepromatous leprosy. Three specimens were taken from the first patients. All five isolates were arginine-positive and their antibiotic sensitivity was identical with only one slight exception.

Humans↗
PubMed1976

The nature of the training response; peripheral and central adaptations of one-legged exercise.

13 male subjects were studied and placed in 3 groups. Each group exercised one leg with sprint (S), or endurance (E) training and the other leg oppositely or not at all (NT). Oxygen uptake (Vo2), heart rate and blood lactate were measured for each leg separately and for both legs together during submaximal and maximal bicycle work before and after 4 weeks of training with 4-5 sessions per week. Muscle samples were obtained from the quadriceps muscle and assayed for succinate dehydrogenase (SDH) activity, and stained for myofibrillar ATPase. In addition, eight of the subjects performed after the training two-legged exercise at 70% Vo2 max for one hour. The measurements included muscle glycogen and lactate concentrations of the two legs as well as the blood flow and the a-v difference for O2, glucose and lactate.

Adaptation, Physiological↗
PubMed1975

Fine structure of single fibres of human skeletal muscle.

Individual muscle fibres were separated from freeze-dried needle biopsies and classed as type I or type II fibres according to their myofibrillar ATP-ase. Portions of the same fibres were processed for electron microscopy and their fine structure examined. Type I fibres were found to have thicker Z-bands and more mitochondria and lipid droplets than the type II fibres.

Adenosine Triphosphatases↗
PubMed1975

Studies on the pathogenicity for rat of a mycoplasma isolated from rheumatoid arthritis.

The pathogenicity for rat of M. arthritidis strain Jasmin and strain 20-P from rheumatoid synovial tissue were studied. Only strain Jasmin produced signs of illness in four of the 12 rats infected. A mycoplasma was isolated from three tissue specimens. Ten of the 48 rats investigated showed mycoplasma antibodies. Five rats showed minor inflammatory changes in the distal joints of the limbs. The failure to induce arthritic symptoms in rats inoculated with strain 20-P from rheumatoid arthritis may be due to its 10-year long storage outside the animal host.

Animals↗
PubMed1975

Metabolic characteristics of fibre types in human skeletal muscle.

Muscle biopsy samples were obtained from healthy subjects in order to evaluate quantitative differences in single fibres of substrate (glycogen and triglyceride) and ion concentrations (Na+ and K+) as well as enzyme activity levels (succinate-dehydrogenase, SDH; phosphofructokinase, PFK; 3-hydroxyacyl-CoA-dehydrogenase, HAD; myosin ATPase) between human skeletal muscle fibre types. After freeze drying of the muscle specimen fragments of single fibres were dissected out and stained for myofibrillar-ATPase with preincubations at pH's of 10.3, 4.6, 4.35. Type I ("red") and II A,B, and C ("white") fibres could then be identified. Glycogen content was the same in different fibres, whereas triglyceride content was highest in Type I fibres (2-3 X Type II). No significant differences were observed for Na+ and K+ between fibre types. The activity for the enzymes studied were quite different in the fibre types (SDH and HAD, Type I is approximately 1.5 X Type II; PFK Type I is approximately 0.5 X Type II, Myosin ATPase Type I is approxiamtely 0.4 X Type II). The subgroups of Type II fibres were distinguished by differences in both SDH and PFK activities (SDH, Type II C is greater than A is greater than B; PFK, Type II B is greater than A is approximately C). It is concluded that contractile and metabolic characteristics of human skeletal fibres are very similar to many other species. One difference, however, appears to be than no Type II fibres have an oxidative potential higher than Type I fibres.

Adenosine Triphosphatases↗
PubMed1975

Mycoplasma antibodies in rheumatoid arthritis.

Sera of 100 patients under examination at the Outpatient Department of the Rheumatism Foundation Hospital were studied by the indirect hemagglutination technique, using both mycoplasma reference strains, and isolates from RA and SLE as antigens. The series consisted of five groups: I, definite RA (49 patients); II, probable RA (11); III, possible RA or nonspecific inflammatory arthritis (34); IV, osteoarthrosis (2); V, Reiter's disease (4). Mycoplasma antibodies in titres of 16 or higher were encountered in groups I-IV in 26, 8, 19, and one case respectively. Twenty-one out of 106 blood donors had antibodies against an isolate from RA and/or M. arthritidis strain PG 6. The titres found were 16 or 32, except in two cases, 128. In the definite RA group, 21 out of 26 patients possessing mycoplasma antibodies, showed titres of 16 or higher against isolates from RA and/or SLE, 12 against M. arthritidis strain PG 6 and/or Campo, 8 against M. fermentans, and 6 against a T-strain from NGU. Antibodies against M. arthritidis strain Campo were found more often than against strain PG 6. The longer the duration of the arthritic symptoms was, the more frequent seemed also to be the occurrence of mycoplasma antibodies.

Antibodies, Bacterial↗
PubMed1975

Recent progress in mycoplasma research.

Today, 12 years after the identification of Eaton agent as a mycoplasma, much new information on this infection has accumulated. Better methods have become available, which will be helpful in determining whether other mycoplasmas might be human pathogens, e.g., some ureaplasmas in nongonococcal urethritis. Experimental mycoplasma infections in birds and animals have revealed common features with immune complex diseases in man. They may serve, therefore, as useful models for human mycoplasma disease. However, the most important finding in recent mycoplasma research has been the isolation of mycoplasma viruses. Viruses belonging to three different groups have been discovered. It will be interesting to study whether the virus determines the pathogenicity of mycoplasmas or not.

Acholeplasma laidlawii↗