Search PubMed⌕ Search

Biomedical subjects

M Olsson

Publications and source records attributed to M Olsson.

At least 163 records · Page 9Linked to original sources
PubMed1982

Blood glutathione-peroxidase levels in skin diseases: effect of selenium and vitamin E treatment.

Blood glutathione-peroxidase (GSH-Px) was determined in 61 healthy subjects and 506 patients with various skin disorders. Depressed levels were observed in patients with psoriasis, eczema, atopic dermatitis, vasculitis, mycosis fungoides and dermatitis herpetiformis. Low values of GSH-Px were also found in some patients with pemphigoid, acne conglobata, polymyositis, rheumatoid arthritis, scleroderma and systemic lupus erythematodes. Vegetarian diet, malnutrition and alcohol abuse could possibly account for the low values in some patients. Fifty patients with low GSH-Px levels were treated with tablets containing 0.2 mg selenium as Na2SeO3 and 10 mg tocopheryl succinate. The GSH-Px levels increased slowly within 6-8 weeks of treatment. The clinical effect was encouraging and calls for controlled studies.

Adolescent↗
PubMed1980

Repair of alkylated DNA in Escherichia coli. Methyl group transfer from O6-methylguanine to a protein cysteine residue.

O6-Methylguanine residues disappear from alkylated DNA by an inducible repair process in Escherichia coli. The reaction can be studied in a cell-free system, using DNA treated with a radioactive methylating agent as substrate. The disappearance of labeled O6-methylguanine from DNA is not accompanied by release of radioactive material in an acid-soluble form. Instead, the methyl group of O6-methylguanine appears to be transferred enzymatically to a protein cysteine residue. Radioactively labeled S-methylcysteine has been identified in protein hydrolysates after incubation of the alkylated DNA with a partly purified E. coli methyltransferase activity. The radioactive amino acid residue shows properties identical with those of S-methylcysteine by automatic amino acid analysis and paper chromatography in several solvent systems. Moreover, oxidation of the compound with hydrogen peroxide yields a product which co-chromatographs with S-methylcysteine sulfone.

Alkylation↗
PubMed1977

Genetic control of alpha-fetoprotein synthesis in the mouse.

To approach the genetic mechanism that turns off the synthesis of alpha-fetoprotein (AFP) after birth, we assumed that a change in this mechanism might affect the low basal level of AFP that can be detected in the adult organism. The concentration of AFP was therefore determined for serum from adult mice of 27 different inbred strains. With one exception, this basal level was between 34 and 173 ng/ml, which is about 10(5)-fold less than the serum concentration at birth. In one strain, BALB/c/J, the AFP level was found to be considerably increased; it was about 10-fold higher than in other strains at 9-10 wk of age. Two other substrains of BALF/c mice showed normally low AFP levels. Kinetic studies show that the rate with which AFP disappears from serum after birth is reduced in BALB/c/J mice as compared to other strains. The increased AFP level of BALB/c/J mice appears to be due to an increased rate of synthesis of AFP, since the rate of catabolism of AFP was found to be normal in these mice. Genetic analysis was performed by crossing BALB/c/J mice with mice having an ordinary AFP level, followed by determination of AFP levels in mice of the F1 and F2 generations as well as in back-cross mice. The results clearly indicate that the increased AFP level in BALB/c/J mice is controlled by a single recessive Mendelian gene, which has been named Raf (for regulation of alphafetoprotein). The Raf gene could be directly involved in the regulation of AFP synthesis, but it may also control AFP levels only indirectly, e.g., by regulating the synthesis of a hormone that controls AFP synthesis.

Age Factors↗
PubMed1977

Breast milk composition in Ethiopian and Swedish mothers. III. Amino acids and other nitrogenous substances.

The content of amino acids and other nitrogenous substances was determined in milk samples from Ethiopian and Swedish mothers. The Ethiopian mothers were divided into two groups, one with children having low weight for age and one with children having standard weight for age. All children were in the age range 2 to 5 months, and there were eight in each group. The main findings were as follows: 1) The mean daily milk volumes and total daily nitrogen content in the milk were found to be similar in all three groups. The Swedish group had a significantly lower nitrogen content per milliliter than did the Ethiopian group with low weight for age. 2) The total amino acid composition of the milk was almost identical in the three groups studied except for the tyrosine value, which was significantly lower in the Ethiopian standard group than in the low weight for age group. The composition corresponded well with previous findings. 3) The protein fraction constituted 90 to 92% of the total amino acids, the peptide fraction 4 to 5%, and the free amino acids 5%. 4) The concentrations of free amino acids in milk were lower (2 to 6 times) than in plasma, except for glutamic and aspartic acid. The taurine concentration was much higher in milk than in plasma. Only the urea levels in milk and plasma were significantly correlated. The implications of these findings in child health are discussed.

Adolescent↗
PubMed1975

Rubidium redistribution after suprarenal caval ligation in the rat.

The distribution of infused 86 Rb Cl between different organs was followed for 48 hours. When SRVCL was perfused 15 hours after the 86 Rb Cl infusion, there was a redistribution with loss of Rb from the kidneys and the thigh musculature and an increase in the Rb concentration in the liver and shoulder musculature.

Animals↗
PubMedDate not supplied

Promiscuity in sand lizards (Lacerta agilis) and adder snakes (Vipera berus): causes and consequences.

We review postcopulatory phenomena in the Swedish sand lizard (Lacerta agilis) and adder (Vipera berus), and in particular, links between female promiscuity, determinants of paternity, and offspring viability. In both species, females mate multiply and exhibit a positive relationship between the number of partners and offspring viability. We conclude that this relationship is most likely the result of variable genetic compatibility between mates arising from postcopulatory phenomena, predominantly assortative fertilization with respect to parental genotypes. However, males who were more successful at mate acquisition were also more successful in situations of sperm competition, suggesting a possible link between male (diploid and haploid) genetic quality per se and probability of fertilization. Neither the number of partners nor the number of matings influenced the risk of infertility in sand lizards, suggesting that selection for reduced risk of infertility is not a sufficient explanation for maintaining female promiscuity in this population. Finally, we conclude that the relatively low genetic variability exhibited by our study populations may have facilitated detection of genetic benefits compared to more outbred ones. However, recent work derived from outbred populations in other taxa suggest a greater generality of the principles we discuss than previously may have been appreciated.

Animals↗
PubMedDate not supplied

Thyroid tissue characterization by proton magnetic resonance relaxation time determination.

Measurements were performed at 37 degrees C on 49 fresh samples excised from cancerous (n = 16) or non-malignant (n = 33) thyroid tissues of 23 patients. They were carried out for protons at a frequency of 10.7 MHz with pulse sequences (90 degrees-t-90 degrees) and (90 degrees-t-180 degrees-t) for T1 and T2 respectively. The estimates were correlated to histopathology with quantitative measurements of the proportions of colloid, thyroid epithelium, fibrosis, and haemorrhage tissue. Discriminant analysis of malignant and non-malignant tissues using T1 and T2 values, was not successful. T1 and T2 values were correlated to each other. Both were correlated to the proportions of water, thyroid epithelium and haemorrhage and inversely correlated to the amount of colloid. Multiple regression analysis revealed that T2 values were more tissue-specific than T1 values. The analyses indicate possibilities to identify different thyroid tissues by magnetic resonance imaging, especially by T2 weighted MR images.

Body Water↗
PubMedDate not supplied

Tooth-implant and implant supported fixed partial dentures: a 10-year report.

PURPOSE: The use of implants for prosthetic rehabilitation of partially edentulous patients is increasing. However, the possibilities of placing implants in the posterior part of the mandible are often limited. The purpose of this longitudinal study with 10 years of follow-up was to evaluate the use of short implants supporting fixed partial dentures (FPD) in the posterior part of the mandible, and to compare implant supported FPDs to tooth-implant supported FPDs. MATERIALS AND METHODS: The patient material comprised 23 patients with residual mandibular anterior teeth, and each patient received FPDs unilaterally. On one side the FPD was supported by two implants, and on the other side by one implant and one tooth, thus permitting intraindividual comparison. The distribution of the two types of FPDs in each jaw was randomized. Implant success rates, marginal bone changes, and mechanical complications were studied. RESULTS: The tooth-implant connection did not demonstrate any negative influences on the overall success rates for the 10-year period, nor were the shorter implants found to be less favorable. CONCLUSION: It is suggested that a prosthetic construction supported by both a tooth and an implant may be recommended as a predictable and reliable treatment alternative in the posterior mandible.

Alveolar Bone Loss↗