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Biomedical subjects

E Jansson

Publications and source records attributed to E Jansson.

At least 73 records · Page 4Linked to original sources
PubMed1996

Muscle ubiquinone in healthy physically active males.

Thirty-five (35) healthy physically active males had muscle biopsies taken from their vastus lateralis muscle to analyze for ubiquinone (vitamin Q, UQ), oxidative (muscle fiber types expressed as %ST and citrate synthase activity, CS) and fermentative (lactate dehydrogenase, LD) profiles. Graded cycle ergometer exercise to determine the intensities corresponding to onset of blood lactate accumulation set to 4.0 mmol x l-1 (WOBLA) and symptom limited exercise ('maximal', WSL) were also undertaken. Eleven (11) subjects had also recently participated in a marathon race. UQ was positively related to CS (r = 0.67, p < 0.001) and %ST (r = 0.60, p < 0.001) but not to LD. UQ was also positively related to exercise capacity and/or marathon performance (e.g. WOBLA x kg-1 BW, r = 0.70, p < 0.001). It was suggested that muscle UQ allocation in man was related to variables describing molecular oxygen availability, respiratory activity and oxidative energy releasing processes but not to fermentation activity. UQ allocation to ST fibers/CS activity was suggested to be due to the double role of UQ: 1) as a mitochondrial coenzyme (CoQ10) and 2) as a nonspecific antioxidant.

Adult↗
PubMed1996

Different responses of skeletal muscle following sprint training in men and women.

Six male and ten female physically active students performed 30-s sprint training on a cycle ergometer three times a week for 4 weeks, to investigate the training responses of skeletal muscle and to evaluate possible sex differences in this respect. Three repeated sprint tests with a 20-min rest in between were performed and muscle biopsies from the vastus lateralis muscle were taken before and after the training period. Mean power (average of sprint I-III) and type IIB cross-sectional fibre area increased only in the women (7% and 25% respectively) following sprint training, resulting in a decreased sex difference. There was an increase in total lactate dehydrogenase (LD) activity following sprint training in both sexes, although the levels were lower in the women both before and after training. Glycogen content increased and the activity of LD iso-enzyme 1 decreased in the women, but not in men. It was hypothesised that both the smaller areas of type II fibres and lower activity of LD generally seen in women may be due in part to less frequent activation of type II fibres in women than in men. If this were the case, the women should respond to sprint training (a type of training that activates type II fibres) to a relatively greater extent than men. That the observed increase in type IIB fibre area in response to sprint training was greater in the women than in men supported the hypothesis of the study. However, the results for LD activity, which showed a similar response in the men and the women, did not support the hypothesis.

Adult↗
PubMed1996

Cardiac nuclear hormone receptor mRNA in heart failure in man.

Eight donor hearts and six explanted hearts due to dilated cardiomyopathy, normal skeletal muscle and liver were analysed. Glucocorticoid receptor (GR) and thyroid hormone receptor (T3R) isoforms beta 1, beta 2, alpha 1 and alpha 2 mRNA abundance were determined by solution hybridization. Both GR and T3R receptor mRNA isoforms were lower in the myocardium as compared to skeletal muscle and in particular to liver. GR mRNA abundance was higher than that of any T3R isoform while the sum of ligand-binding isoforms (beta 1, beta 2 and alpha 1) were similar in the myocardium and in skeletal muscle as opposed to the liver where GR mRNA was higher. GR mRNA abundance was similar in right and left ventricles from donor hearts and in cardiomyopathy. T3R beta 1 showed higher levels in the right ventricle with higher levels in cardiomyopathy as compared to donor heart. T3R isoform alpha 1 and especially the alpha 1/alpha 2 ratio were lower in left ventricle in cardiomyopathy compared to donor hearts. In conclusion, GR and T3R isoforms mRNA abundance are low in the human myocardium. In the failing myocardium GR and T3R beta 2 and alpha 2 show no signs of reactivity while T3R beta 1 and alpha 1 mRNA adapt.

Adolescent↗
PubMed1996

Development of muscular endurance and strength from adolescence to adulthood and level of physical capacity in men and women at the age of 34 years.

This study investigated the development of muscular endurance and strength from the age of 16 to the age of 34 and the fitness components at the age of 34 in men and women. A randomly selected group consisting of 220 boys and 205 girls was tested in 1974 and reinvestigated 18 years later. Muscular endurance and strength increased significantly in 4 of the 5 remeasured tests for the men; bench press increased by 58%, two-hand lift by 20%, hand grip by 16% and Sargent jump by 8%. For the women there was a significant increase in bench press and two-hand lift by 25% and 7% respectively, but hand grip and Sargent jump decreased with a few per cent. The hip and trunk flexion test, sit-up, decreased remarkably in both men (58%) and women (78%). At the age of 16 physical capacity was significantly higher in all tests in the men. This was also the situation at the age of 34 except for VO2 max in ml.kg-1.min-1 and muscular endurance in the back muscles. There were no differences in flexibility between men and women except for less flexibility in the hamstring muscles in the men. The result of the balance test was significantly better in the men.

Adolescent↗
PubMed1996

Physical activity pattern in men and women at the ages of 16 and 34 and development of physical activity from adolescence to adulthood.

The aim of this study was to investigate gender-related differences in physical activity patterns at the ages of 16 and 34 and to analyse those factors that might contribute to an explanation of physical activity habits in adulthood. A randomly selected group, consisting of 220 boys and 205 girls, was tested in 1974 and reinvestigated in 1992 by means of a questionnaire. Eighty-eight per cent participated in the reinvestigation. At the age of 16 more boys (69%) than girls (51%) participated in some sports activity in their leisure time. The results showed an overall decrease in participation in vigorous physical activity, although participation in light physical activity remained relatively constant. At the age of 34, there was no difference in overall physical activity between men and women, but the men exercised more vigorously (44% vs. 29%). Early experience of physical activity at the age of 16 decreased the risk of becoming inactive in adulthood. At the age of 34 cohabiting for the men, and having children and high socio-economic class for the women, increased the risk of being physically inactive in adulthood, whereas positive beliefs about health effects of exercise decreased the risk for both men and women.

Adolescent↗
PubMed1995

Effect of spasmolytic drugs on esophageal foreign bodies.

Muscle spasm has been proposed as the cause for esophageal food impaction. The aim was therefore to treat esophageal foreign bodies with spasmolytic drugs influencing both striated and smooth muscles of the esophagus. A multicenter, placebo-controlled, double-blind study of glucagon and diazepam was undertaken in 43 patients. The foreign body disimpacted in 9 of 24 patients given active substances and in 6 of 19 patients given placebo; there was no significant difference between these two groups. Almost all disimpactions occurred several hours after injection of the drugs. The hypothesis of muscle spasm as an important cause of esophageal obstruction was rejected. Medical therapies for food disimpaction other than spasmolytic drugs have to be investigated.

Adolescent↗
PubMed1995

Do highly physically active females have a lowered basal metabolic rate?

In several studies estimated energy intake has been found to be low compared with estimated energy expenditure in female athletes. It has therefore been suggested that female athletes may have a depressed basal energy expenditure (BMR). The main purpose of the present study was to explore this possibility by measuring BMR in physically extremely active females. Eight female dancers and 7 controls with low physical activity, all musicians, were studied; the variables measured included body weight, height, skinfold thickness and total body potassium. BMR was measured by indirect calorimetry. In conclusion, the present study lends no support to the idea of a lowered basal metabolic rate in female athletes as an explanation of the general finding of a lower estimated energy intake than energy expenditure in this type of subjects.

Adult↗
PubMed1995

Beta 1 and beta 2 adrenoceptor ligand and mRNA expression in dilated cardiomyopathy.

beta 1 and beta 2 adrenoceptor ligand activity has been shown to be down-regulated in failing myocardium. It is the aim of this study to test the hypothesis that also mRNA levels are down-regulated in dilated cardiomyopathy. beta 1 and beta 2 adrenoceptor ligand activities and mRNA expressions were analyzed in left ventricular biopsies from six organ donor hearts, in papillary muscles from seven patients operated on for mitral regurgitation, and in six explanted hearts as the result of dilated cardiomyophathy. mRNA levels were determined by solution hybridization. beta 1 ligand activity was decreased in the cases of mitral regurgitation (p < 0.01) and dilated cardiomyopathy (p < 0.001). beta 2 ligand activity did not differ between the three groups. mRNA expression was depressed in mitral regurgitation regarding both beta 1 (p < 0.001) and beta 2 (p < 0.01), while no differences were observed in dilated cardiomyopathy as compared to the donor hearts. The regulation of beta 1 and beta 2 adrenoceptor ligand activity and mRNA expression appears to follow a specific pattern in dilated cardiomyopathy. The specific down-regulation of beta 1 ligand activity seems to occur at a posttranslational level.

Adipose Tissue↗
PubMed1995

Na,K-ATPase receptor subunits alpha 1, alpha 2 and alpha 3 mRNA in dilated cardiomyopathy.

Na,K-ATPase receptor density has been shown to be down-regulated with decreasing ejection fraction in patients with chronic heart failure. It was the aim of the present study to determine whether down-regulation is detected also at the mRNA level. Six donor hearts and six explanted hearts due to dilated cardiomyopathy (ejection fraction 23 +/- 5%) were analyzed. RNA was extracted. Quantitative Na,K-ATPase receptor catalytic subunit alpha 1, alpha 2 and alpha 3 mRNA expression was determined by solution hybridization. No cross-reactivity occurred between the three probes. alpha 1 mRNA was expressed at about 5 and 10 times higher (p < 0.001) concentrations than alpha 2 and alpha 3 mRNA, respectively, and alpha 2 mRNA higher (p < 0.001) than alpha 3. There were no differences between right and left ventricles and between donor hearts and patients with dilated cardiomyopathy. In conclusion, Na,K-ATPase alpha 1 mRNA is the predominant subunit expressed in human myocardium. Depressed ejection fraction in dilated cardiomyopathy is not associated with changed mRNA subunit expression. Documented downregulation of Na,K-ATPase activity, therefore, may be associated with the structural and membrane-related beta subunit or posttranscriptional modification of the catalytic subunits.

Adolescent↗
PubMed1994

Prediction of physical activity level in adulthood by physical characteristics, physical performance and physical activity in adolescence: an 11-year follow-up study.

The purpose of the study was to investigate to what extent the physical activity pattern in adulthood can be predicted by physical characteristics, performance and activity in adolescence. A group of 62 men and 43 women completed a questionnaire concerning physical activity during their leisure time at the ages of 16 and 27 years. An activity index produced from the questionnaire. At the age of 16 years, the subjects were also tested for strength (strength test battery) and running performance (9-min run). Maximal oxygen uptake (VO2max) was estimated from a submaximal test and a muscle biopsy specimen was taken and analysed for fibre types (percentages of types I, IIA, IIB). The proportion of subjects engaged in some kind of physical activity during their leisure time was approximately 70% among the women and 80% among the men at both ages. The time spent on physical activity (minutes per week) decreased with age for the men but not for the women. The women devoted less time to physical activity than the men both at age 16 and 27 years. The attitude to endurance activities had changed to a more positive attitude among the women and to a less positive attitude among the men at age 27 years. The aerobic potential (VO2max and percentage of type I fibre), running performance, strength performance, physical activity and marks in physical education at age 16 years explained 82% of the physical activity level in adulthood for the women and 47% for the men.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Muscle strength from adolescence to adulthood--relationship to muscle fibre types.

The aim of the present study was to reinvestigate muscle strength and the relationship to muscle fibre and the level of physical activity in adult men and women previously studied during adolescence. A group of 55 men and 26 women were tested for maximal strength (handgrip, Sargent jump and two-hand lift) and completed a questionnaire concerning physical activity during their leisure time (activity index) at the ages of 16 and 27 years. Biopsy specimens were taken from the vastus lateralis and analysed for fibre type (percentage of I, IIA, IIB) and fibre area (area I, area IIA, area IIB). The sex differences in strength increased from age 16 to 17 years. Body dimension, sex, percentage of type II, mean fibre area and the activity index contributed to explaining 50-75% of the strength at both ages. Different changes in relationship between fibre type composition and strength in women and men was seen with increasing age. In the women, the relationship between strength and the percentage of type II fibres changed with age (from 16 to 27 years of age) from a positive correlation (only Sargent jump) to negative correlations for all the strength tests, i.e. the more type I fibres the stronger the subject. A positive correlation between strength and the level of physical activity during leisure time was revealed in the women at both ages. The positive correlation between strength and type II fibres in the 16-year-old men had disappeared at age 27. No systematic relationships between strength and the level of physical activity were seen in the men at either 16 or 27 years of age. It is suggested that women may be more dependent on physical activity than adult men to develop strength and the percentage of type I fibres reflects the degree of physical activity among adult women but not among adolescent women.

Adolescent↗
PubMed1994

AMP deaminase in skeletal muscle of healthy males quantitatively determined by new assay.

A new, sensitive assay for the quantitative determination of AMP deaminase activity in human skeletal muscle is presented. The method is based on the determination of the direct product of the AMP deaminase reaction, the formed IMP, by high performance liquid chromatography (HPLC). In order to evaluate the relationship between AMP deaminase activity on the one hand and the contractile and metabolic characteristics of the muscle and the physical performance on the other, muscle biopsies were taken from 20 male subjects. The subjects also performed a 30 s sprint test on a cycle ergometer. The inter-individual variation in AMP deaminase activity was large, ranging from 5.4 to 27.4 microkat g-1 dry muscle. AMP deaminase was positively correlated with phosphofructokinase (PFK), the marker of the glycolytic capacity of the muscle, but there was no correlation with enzymes of oxidative metabolism, such as 3-hydroxyacyl-CoA dehydrogenase and citrate synthase, or with the activity of myokinase and lactate dehydrogenase. There was no significant correlation between AMP deaminase activity and the proportion of the different muscle fibre types. A weak positive correlation was found between the sprint performance and the AMP deaminase activity. In conclusion, the HPLC assay was found to be a fast, sensitive and reliable method for the quantitative determination of AMP deaminase activity in muscle. A direct relationship between AMP deaminase activity on the one hand and glycolytic capacity and sprint performance on the other was found. However, no relationship to oxidative capacity or contractile properties was found.

AMP Deaminase↗
PubMed1994

Clinical evaluation of the CDI System 400 blood gas monitor.

The CDI 400 blood gas monitor was evaluated by investigating its clinical performance in 30 patients undergoing cardiac surgery requiring cardiopulmonary bypass. Arterial and venous blood samples were withdrawn during stable hypothermic conditions. Reference analysis was performed on the ABL4 blood gas analyzer. A total of 229 samples were included for calculations of bias and precision. Simple regression analysis was utilized to illustrate the relationship between the tested monitor and its reference. Results revealed an acceptable agreement for pH and arterial pO2 measurements. Venous pO2 bias and precision were poor (+0.76 +/- 1.07 kPa). Arterial and venous pCO2 were generally overestimated (+0.5 +/- 0.4 kPa and +0.2 +/- 0.4 kPa). Performance given as correlation coefficients indicated a similar pattern. Slopes and intercepts deviated from the line of identity for all parameters analysed. In summary: the CDI 400 is a valid instrument in guiding the perfusionist with crucial trend information. However, its general performance implies that a reference blood gas analyser is still needed.

Aged↗
PubMed1994

Continuous venous oximetry: a comparative study between the CDI 100 and the Bentley OxySat II.

Two in-line oxygen saturation monitors, the CDI 100 and OxySat II, were evaluated in the clinical setting. Eighty-seven venous blood samples were drawn during 20 elective cardiopulmonary bypass procedures. Monitor readings were compared to OSM III co-oximeter values. The results revealed that saturation (%) determination was biased, -3.16 +/- 2.21 SD for the CDI 100 and -0.34 +/- 2.17 SD for the OxySat II. Hemoglobin (g/dl) and hematocrit (%) measurement, available only for the CDI 100, resulted in a bias of +5.54 +/- 5.68 SD and +1.94 +/- 1.78 SD, respectively. It was concluded that both monitors operated within clinically acceptable limits, with a more favorable outcome for the OxySat II.

Aged↗
PubMed1993

Rapid identification of Renibacterium salmoninarum using an oligonucleotide probe complementary to 16S rRNA.

Bacterial kidney disease in salmonid fish is caused by the slow-growing Gram-positive rod, Renibacterium salmoninarum. The partial sequence of 16S rRNA from R. salmoninarum was determined and compared with published bacterial 16S rRNA sequences. From this sequence information, a 30-bases-long oligonucleotide was designed and used as a specific probe for identification of R. salmoninarum in filter hybridization experiments. Strong specific hybridization signals were observed for all strains of R. salmoninarum tested. Furthermore, no cross-hybridization could be seen against 22 other bacterial species, among them other salmonid fish pathogens. The detection limit for the probe in direct filter hybridization by the dot-blot technique was 2.5 x 10(4) bacteria. It was also possible to detect R. salmoninarum in clinical samples by direct filter hybridization.

Animals↗
PubMed1993

Running capacity from adolescence to adulthood. Relationship to physical characteristics.

It has been shown earlier that the proportion of slow twitch (type I) fibres in the leg musculature is directly related to running performance in boys but not in girls at the age of 16. The purpose of the present study was to determine whether this pattern remains in adulthood. Forty-one men and 19 women were tested at the age of 16 and 27 years. Muscle biopsy specimens were obtained from the vastus lateralis and analysed for fibre type (I%, IIA%, IIB%). Maximal oxygen uptake (VO2max) was estimated from a submaximal exercise test. Running performance (9-min run) was assessed in a modified Cooper test. At age 16, the 9-min run was positively correlated with type I% and VO2max for the men. For the women, the 9-min run was positively correlated with VO2max but not with type I%. At age 27, the 9-min run was positively correlated with type I % and VO2max for both men and women. The appearance at the age of 27 of a relationship between running performance and type I% in the women could be related to the increase with age in the VO2max found in the women in the present study. These results support an earlier formulated hypothesis that a certain level of VO2max must be reached before peripheral factors such as the muscle fibre type composition are of any significance for the performance in a 9-min run.

Adolescent↗