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O Andersson

Publications and source records attributed to O Andersson.

At least 37 records · Page 2Linked to original sources
PubMed1996

On the value of menorrhagia as a predictor for coagulation disorders.

The value of menorrhagia as a predictor for mild bleeding disorders has been very little studied and the results are divergent. In the present study on 30 women with objectively verified menorrhagia, we found a significantly increased prevalence of von Willebrand's disease (20%). By keeping a strict sampling and laboratory routine, and by restricting sampling to cycle days 5-7, we also obtained a very low interindividual variation of von Willebrand factor and coagulation factor VIII. We conclude that menorrhagia is a valuable predictor for coagulation and platelet disorders, and that time of sampling is of importance. This should be considered in the investigation of menorrhagia, and can be a guideline in looking for mild bleeding disorders.

Adult↗
PubMed1996

Survey of consumption fish from Swedish waters for chlorinated pesticides and polychlorinated biphenyls.

In this survey eighty-seven samples of consumption fish comprising mainly of salmon, pike, eel, herring, whitefish, sea-trout, perch, pike-perch, mackerel, cod, flounder, plaice and sole collected between 1992-1993 have been analysed for the levels of chlorinated pesticides and polychlorinated biphenyls (PCBs). Considering the diversity in the sizes and assortment, locations, and time of catch, the samples are deemed to represent the normal fish variety available to the local people at various seasons of the year. Virtually all the samples contained CB-153 levels below the new established maximum limit of 0.1 mg/kg fresh weight. Results are compared with those obtained between 1985 and 1993. Neither the total PCB (on fat weight basis) nor CB 153 as a marker showed any clear trend for most of the fish species analysed, particularly for the short period 1991-1993. The pesticides, on the other hand, showed a rather good downward trend up till 1991; some of them seem to have virtually attained a steady state after 1991.

Animals↗
PubMed1996

Importance of a novel oxidative mechanism for elimination of intracellular cholesterol in humans.

We have recently demonstrated that cultured human alveolar macrophages efficiently convert cholesterol into excretable 27-oxygenated products. We show here that increasing the intracellular concentration of cholesterol by a factor of 10 leads to about a twofold increase in the excretion of 27-oxygenated products from cultured macrophages. Inhibition of the sterol 27-hydroxylase caused a significant intracellular accumulation of cholesterol. A direct comparison was made between flux of cholesterol and 27-oxygenated products from macrophages preloaded with [4-14C]cholesterol. Under the specific conditions employed with fetal calf serum in the culture medium, the flux of 27-oxygenated products was about 10% of that of cholesterol. Since the sterol 27-hydroxylase, which converts cholesterol to 27-oxygenated products, is present in many cell types, we suggest that 27-oxygenation is a general mechanism for removal of intracellular cholesterol. To evaluate this hypothesis, we measured the net uptake by the human liver of circulating 27-oxygenated products, which was found to be about 20 mg/24 h. This uptake corresponds to approximately 4% of the bile acid production, assuming quantitative conversion into bile acids. It is concluded that the 27-hydroxylase pathway is of significance for elimination of extrahepatic cholesterol.

Cells, Cultured↗
PubMed1996

The degree of natural allergen exposure modifies eosinophil activity markers in the circulation of patients with mild asthma.

We have previously found that CD9, CD11b, and intracellular ECP (EG2) may be used as activity markers for eosinophils in vitro. The main object of the present study was to determine whether these markers can reflect eosinophil activation in vivo in relation to allergen exposure. for this purpose, six patients with a history of allergic rhinitis and occasional asthma symptoms during the pollen season participated. Blood donors served as controls. Peripheral blood eosinophils were analyzed according to the FOG method and flow cytometry, before and during one birch pollen season with high pollen load (HPL) and one with low pollen load (LPL). The CD9 expression on peripheral eosinophils from the patients was significantly increased both before (P < 0.05) and during (P < 0.01) HPL season, and CD11b expression solely during HPL season (P = 0.01) as compared to controls. The intracellular expression of the EG2 epitope was increased before (P < 0.01) and during (P < 0.05) HPL season, and increased significantly (P < 0.05) during season as compared to before. No changes were observed before and during LPL season. The proportion of eosinophils was increased both before (P < 0.05) and during (P < 0.001) the HPL season as compared to controls. The markers CD9, EG2, and, to a lesser extent, CD11b seem to detect activated eosinophils in the circulation, whereas EG2 may also reflect increased antigen exposure during season.

Adult↗
PubMed1995

Glass-ceramic-coated titanium hip endoprosthesis. Experimental study in rabbits.

Titanium alloy hip endoprostheses coated with a bioactive glass ceramic (BGC) were followed in rabbits. All test endoprostheses remained stable, and image analysis showed an average of 78% bonding of the BGC-coated implants to bone at 52 weeks. The uncoated Ti-alloy controls demonstrated an average of 37% bone coverage after 52 weeks. By scanning electron microscopy the thickness of the BGC reaction layer was found to stabilize at 60 microns after bioactive bone bonding. The results indicate that the BGC coating must be thicker than the reaction layer to prevent detachment from the core metal.

Alloys↗
PubMed1995

Allergen challenge-induced entry of alpha 2-macroglobulin and tryptase into human nasal and bronchial airways.

BACKGROUND: Microvascular-epithelial exudation of bulk plasma may characterize inflammatory airway diseases. This study compares the acute allergen challenge-induced mast cell and exudative responses in nasal and bronchial airways. The focus is on alpha 2-macroglobulin as an index of luminal entry of plasma exudates. METHODS: Separate nasal and bronchial allergen challenges were carried out outside the pollen season in eight patients with pollen-induced seasonal allergic rhinitis. The levels of different-sized plasma proteins (albumin molecular weight, 66,000 d and alpha 2-macroglobulin molecular weight, 725,000 d) and tryptase were determined in pre- and postchallenge nasal lavage and bronchoalveolar lavage (BAL) fluids. Diluent and increasing doses of allergen were sprayed into the right nasal cavity, and each challenge was followed by a nasal lavage (volume, 15 ml) with a "nasal pool" device (recovery, > 80%). Endobronchial allergen challenge (individual doses) and BAL (volume, 2 x 25 ml) were performed in a lobe bronchus through a fiberoptic bronchoscope (recovery, 30%). Saline challenge and BAL were carried out in the contralateral lung as control. RESULTS: The levels of albumin, alpha 2-macroglobulin, and tryptase increased dose-dependently in postchallenge nasal lavage fluids (p < 0.05) and correlated to nasal symptoms. In particular, albumin and alpha 2-macroglobulin correlated (r = 0.98, p < 0.001). Both alpha 2-macroglobulin and tryptase, but not albumin, were increased in BAL fluids from the allergen-challenged side (p < 0.05). CONCLUSION: Local allergen challenge causes luminal entry of tryptase and alpha 2-macroglobulin in the nose and bronchi of patients with allergy. We suggest that mast cell and plasma exudation responses may be similar in human nasal and bronchial airways and that albumin levels (in BAL fluids) may not well reflect the exudation process in bronchial airways.

Adult↗
PubMed1994

Atherosclerosis and sterol 27-hydroxylase: evidence for a role of this enzyme in elimination of cholesterol from human macrophages.

27-Hydroxycholesterol was found in surprisingly high amounts in atherosclerotic human femoral arteries. When human macrophages were cultured in a medium containing serum, there was a significant transfer of 27-hydroxy-cholesterol and 3 beta-hydroxy-5-cholestenoic acid from the cells into the medium. Sterol 27-hydroxylase (EC 1.14.13.15) is likely to be responsible for formation of the two products as shown by use of immunoblotting, a specific inhibitor, and the 18O-labeling technique. Sterol 27-hydroxylase has the unusual ability to hydroxylate the same methyl group three times to give a carboxylic acid; thus, 3 beta-hydroxy-5-cholestenoic acid is likely to be a direct product of the enzyme. The production of these steroids increased after addition of cholesterol to the culture medium. By using deuterium-labeled cholesterol, it was ascertained that most of the oxidized products were formed from exogenous cholesterol taken up by the cells. 27-Hydroxycholesterol and 3 beta-hydroxy-5-cholestenoic acid are present in the circulation and are efficiently converted into bile acids in human liver. It is suggested that conversion of cholesterol into 27-hydroxycholesterol and 3 beta-hydroxy-5-cholestenoic acid represents a general defence mechanism for macrophages and possibly also other peripheral cells exposed to cholesterol. Absence of this defence mechanism may contribute to the premature atherosclerosis known to occur in patients with sterol 27-hydroxylase deficiency (cerebrotendinous xanthomatosis).

Aged↗
PubMed1994

Heterologous expression of human uteroglobin/polychlorinated biphenyl-binding protein. Determination of ligand binding parameters and mechanism of phospholipase A2 inhibition in vitro.

High level expression of a human polychlorinated biphenyl-binding protein (hPCB-BP; also termed uteroglobin or CC10) was achieved in Escherichia coli. The recombinant protein (rhPCB-BP) constituted approximately 1% of total bacterial lysate proteins as judged from in vitro ligand binding assays using 4,4'-bis([3H]methylsulfonyl)-2,2',5,5'-tetrachlorobiphenyl. rhPCB-BP was purified to homogeneity in its native dimeric form. Saturation analysis experiments indicated a Kd of approximately 69 nM for the binding of 4,4'-bis([3H]methylsulfonyl)-2,2',5,5'-tetrachlorobiphenyl to rhPCB-BP. The average number of binding sites (Bmax) calculated from such experiments on purified rhPCB-BP was 49 nmol/mg of protein and is close to the theoretical value of 1 mol of ligand associating with 1 mol of dimeric protein. Purified rhPCB-BP was also found to cause a dose-dependent inhibition of the enzyme porcine pancreatic phospholipase A2 (PLA2) in vitro. Increasing the concentrations of calcium abolished the inhibition of PLA2 by rhPCB-BP, suggesting that the protein functions in vitro by sequestering Ca2+, an essential PLA2 cofactor. This notion was further supported by direct evidence that 45Ca2+ binds to rhPCB-BP. 1 mol of dimeric protein was also found to bind 2 mol of ruthenium red, an organic dye that detects Ca(2+)-binding proteins, with a Kd of 3 microM. This binding was inhibited by Ca2+, with an IC50 of 7 mM. Finally, it was demonstrated that the addition of a high affinity ligand for the protein had no effect on its ability to inhibit PLA2 under conditions of limiting concentrations of calcium, and the addition of Ca2+ did not affect the binding characteristics of the PCB ligand, suggesting that these two properties of the protein are independent. Our results strongly support the notion that ligand binding is a conserved feature of the homologous uteroglobin/PCB-BP/cc10 proteins in different species, whereas our results question the suggested role of these proteins as specific inhibitors of PLA2.

Calcium↗
PubMed1994

Do lowered factor VII levels at extremely high endogenous oestradiol levels protect against thrombin formation?

The purpose of the study was to find a model to study the effect of endogenous oestradiol on haemostasis. Hormones and haemostatic variables were therefore measured before and after in vitro fertilization and egg replacement therapy in 14 women with tubal infertility. The differences between the levels of the haemostatic variables at minimum and maximum levels of oestradiol and progesterone were evaluated. A significant increase in the plasma levels of coagulation factor VIII, von Willebrand factor and fibrinogen was found between samples drawn before stimulation and at the highest oestradiol levels (P < 0.002, P < 0.002 and P < 0.015, respectively). However, coagulation factor VII activity and antigen decreased significantly (P < 0.001 and P = 0.009, respectively). The levels of the coagulation inhibitors protein C and antithrombin decreased (P < 0.003 and P = 0.008, respectively), while that of free protein S increased (P = 0.039). No significant changes were observed in the fibrinolytic variables or in those reflecting thrombin activity (prothrombin fragment 1 + 2, thrombin-antithrombin complexes, soluble fibrin and D-dimers). In conclusion, the increase in the levels of factor VIII, von Willebrand factor, fibrinogen and the decrease in the levels of antithrombin and protein C may, if coagulation is triggered, contribute to a hypercoagulable state. The depressed factor VII levels and the tendency to elevated free protein S levels may constitute a protective mechanism that modulates the coagulation system when levels of oestradiol become extremely high.

Blood Coagulation Disorders↗
PubMed1994

The role of diabetes mellitus and hypertriglyceridaemia as coronary risk factors in treated hypertension: 15 years of follow-up of antihypertensive treatment in middle-aged men in the Primary Prevention Trial in Göteborg, Sweden.

OBJECTIVE: To analyse the importance of diabetes mellitus and hypertriglyceridaemia as potential risk factors for coronary heart disease (CHD) in middle-aged, treated hypertensive men. DESIGN: A prospective, long-term observational study. SUBJECTS: Derived from a random population sample--686 hypertensive men aged 47-54 years at entry--followed for 15 years at a special out-patient hypertension clinic. INTERVENTION AND OUTCOME MEASURES: The patients were mainly treated with beta-adrenoceptor blockers and/or thiazide diuretics. Cardiovascular morbidity was closely monitored during follow-up. RESULTS: In all, 133 subjects suffered a CHD event during follow-up. The presence of diabetes mellitus at entry more than doubled the CHD risk and a 1 mmol l-1 increment of the serum triglyceride level at entry increased the CHD risk by 21%. In multivariate analyses, smoking, the presence of diabetes mellitus at entry, serum cholesterol and signs or symptoms of hypertensive end organ damage were found to be independent risk factors for CHD. In absolute terms the existence of cardiovascular damage was of much greater prognostic importance than were the presence of various metabolic abnormalities. Of the mean in-study variables, both the average serum cholesterol level and the achieved diastolic blood pressure were significantly associated with CHD. However, new diabetes mellitus which developed during follow-up as well as mean serum triglyceride levels were not associated with CHD. CONCLUSIONS: Diabetes mellitus and hypertriglyceridaemia present at the start of treatment have a prognostic impact in treated hypertensive men, whereas when such metabolic disorders develop during drug treatment they seem to be of much less importance. Smoking and already existing evidence of hypertensive end organ damage are of utmost importance for the prognosis in this type of patient.

Adrenergic beta-Antagonists↗
PubMed1993

Reflex sympathetic activation induces acute insulin resistance in the human forearm.

Inferences about the association between sympathetic overactivity and insulin resistance have been drawn from the infusion of sympathomimetic amines in supraphysiological doses. We used the isolated perfused human forearm to investigate the effect of reflex-induced sympathetic nervous system activation on the peripheral utilization of glucose in the skeletal muscles of 14 healthy men. Local hyperinsulinemia in the forearm (132 +/- 25 microunits/mL for 90 minutes) induced a significant increase in the utilization of glucose from baseline (16.4 +/- 3.1 mg.dL-1.min-1 per 100 mL forearm volume) to a plateau (85.7 +/- 15.1 mg.dL-1.min-1 per 100 mL forearm volume) between 40 and 60 minutes of insulin infusion but did not alter the utilization of oxygen. Reflex sympathetic nervous system activation was elicited by unloading of cardiopulmonary receptors with bilateral thigh cuff inflation to 40 mm Hg between 60 and 90 minutes of insulin infusion. Blood flow in the forearm was significantly decreased with inflation of thigh cuffs (average decrease of 19%, p < 0.0001). As a result of thigh cuff inflation, there was a reduction in the utilization of glucose (a decrease of 23%, p < 0.02), whereas oxygen utilization was unchanged. We find that an increase in sympathetic nervous system activation (within the normal range of physiological responses) can cause acute insulin resistance in the forearm of healthy volunteers. The reflex caused no change in oxygen utilization, but the same stimulus elicited a decrease in the utilization of glucose.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Morphology of osteogenesis in bioactive glass interface.

Bone formation around bioactive glass implants (S56.5P4) in the trabeculous subchondral bone in the distal femur of rabbits was studied by histology and scanning electron microscopy. Three types of tissue: bone, connective and hematopoietic tissue developed around the implants resulting in lamellar new bone covering 76% of the surface of the implants at twelve weeks. Bone formation around implants began as woven bone changing mainly to lamellar, osteon like new bone in contact with the S56.5P4 surface. Endochondral ossification was absent. In the area of bone containing hematopoietic tissue, new bone grew often as a thin layer along the implant surface. However, bone seemed to form adjacent to the implant surface through osteo-conduction. Only 21% of the implant surface was covered by loose connective tissue. Some proteoglycan containing thin fluid filled spaces were seen ten days after implantation. In few areas with apparent breakdown of the implant surface decreased amount or no bone formation was observed. Von Kossa method stained the reaction layer as two parallel dark brown lines, toluidine blue as two blue stripes, whereas van Gieson did not stain the reaction layer at all. In conclusion, the present histological results indicate bone bonding, which is a physico-chemical process observed between S56.5P4 implant and host bone.

Animals↗
PubMed1992

On laboratory problems in diagnosing mild von Willebrand's disease.

By providing some examples of variations in the levels of von Willebrand factor antigen (vWF:Ag), ristocetin cofactor, and Factor VIII during one month, the authors wish to emphasize the difficulty of diagnosing mild forms of von Willebrand's disease (vWD), especially type I. In three of 15 normal female volunteers the vWF:Ag levels, on some sampling occasions, were so low (0.25-0.30 IU/mL, normal greater than 0.50 IU/mL) that the diagnosis of vWD type I might be made while on other occasions normal levels were obtained. The coefficients of variation (CV) for vWF:Ag in these three women were 12%, 25%, and 43%. However, CVs of similar magnitude were also observed for "non-diseased" males and females. The ratio F VIII/vWF:Ag also varied greatly. In the three women with suspected vWD it was 36%, 15%, and 34%. A representative level for the entire cycle of vWF:Ag and ristocetin cofactor seems to have been obtained in the follicular phase and therefore it is suggested that in order to make the diagnosis of vWD type I, at least in females, blood samples should be taken in this phase.

Adult↗
PubMed1992

Rat lung polycholorinated biphenyl-binding protein: effect of glucocorticoids on the expression of the Clara cell-specific protein during fetal development.

Certain metabolites of polychlorinated biphenyls (PCBs) are retained in the Clara cells and in the airway lumen of rodent lung due to their interaction with a secretory 13-kDa protein. The expression of this Clara cell-specific, PCB-binding protein (PCB-BP) during the fetal development of the rat lung was studied by means of ligand binding and a monospecific antiserum. The PCB-BP and specific 4,4'-bis([3H]methylsulfony)-2,2',5,5'-tetrachlorobiphenyl binding was first detected on gestational Day 19 and subsequently the levels of PCB-BP and specific ligand binding increased as a function of gestational age. The start site of transcription for the rat PCB-BP gene was determined by primer extension analysis and the information thus obtained was used to develop a quantitative assay for the corresponding mRNA based on solution hybridization and S1 nuclease mapping. The appearance of PCB-BP mRNA during fetal lung development preceded the detection of immunoreactive protein and ligand binding by 1 day. By Day 21, the level of PCB-BP mRNA was 15 ng/100 micrograms total lung RNA which is approximately 30-40% of adult levels. In utero exposure to the synthetic glucocorticoid betamethasone was shown to increase specific 4,4'-bis([3H]methylsulfonyl)2,2',5,5'- tetrachlorobiphenyl binding, PCB-BP protein, and PCB-BP mRNA if administered from gestational Day 18 and onward. By Days 21-22, glucocorticoid treatment resulted in a two- to threefold increase in the levels of specific ligand binding, immunoreactivity, and mRNA, i.e., to approximately adult levels.

Animals↗