PubMed Health⌕ Search

Biomedical subjects

O Andersen

Publications and source records attributed to O Andersen.

At least 55 records · Page 3Linked to original sources
PubMed1997

Effects of acute iron overload on Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss).

Distribution of radioiron to various tissues after intraperitoneal injections was examined in Atlantic salmon and rainbow trout. Liver and spleen were found to be the major iron storage tissues. Injections of 1 or 5 mg iron as ferric ammonium citrate led to a fall in hemoglobin levels in both species after 2 d. Hemoglobin levels returned to normal levels in rainbow trout after 8 d, but Atlantic salmon had not recovered, and Hb levels fell below 3 g/100 mL. In both species, the fall in Hb was associated with a raise in iron levels in spleen and liver, suggesting damage to erythrocytes. Atlantic salmon liver ferritin showed a two- to threefold increase, while rainbow trout showed a sixfold increase, and a more rapid response. The toxic effect of iron in fish appears to be different from the effect in other vertebrates.

Animals↗
PubMed1997

Increased expression of B7-1 costimulatory molecule on cerebrospinal fluid cells of patients with multiple sclerosis and infectious central nervous system disease.

The expression of the costimulatory molecule B7-1 (BB-1; CD80) and its ligand CD28 was investigated on peripheral blood (PB) and cerebrospinal fluid (CSF) T and B lymphocytes and monocytes in 11 patients with relapsing-remitting multiple sclerosis (MS) 21 age-matched healthy controls and 10 patients with central nervous system (CNS) infectious disease (CID). Three channel flow cytometry was used with a novel gating technique in order to unambiguously identify the low numbers of B lymphocytes present in normal CSF. There was a significantly higher fraction of B7-1+ B lymphocytes in the CSF of patients with MS (72%) and CID (69%) when compared with healthy individuals (53%; p < 0.0001 and p < 0.002, respectively). Furthermore, two patients with a clinical picture of encephalitis showed a profoundly increased B7-1 expression on CSF monocytes. Comparison of absolute numbers of B7-1+ B lymphocytes/mL CSF between MS patients and healthy controls revealed a highly increased frequency of these cells among MS patients (235 cells/mL in MS patients versus 3.9 cells/mL in controls; p < 0.0001) with no overlap between the groups, which was otherwise seen for all other analyzed cell populations. We therefore hypothesize that activated B lymphocytes expressing high levels of B7-1 may be of pathogenetic importance in the development and maintenance of the MS disease.

Adolescent↗
PubMed1997

Serum amyloid P component binds to influenza A virus haemagglutinin and inhibits the virus infection in vitro.

Serum amyloid P component (SAP) is a member of the phylogenetically conserved and structurally related group of proteins called pentraxins. SAP exhibits multispecific calcium-dependent binding to oligosaccharides with terminal N-acetyl-galactosamine, mannose and glucuronic acid. The authors report that SAP can bind to influenza A virus and inhibit agglutination of erythrocytes mediated by the virus subtypes H1N1, H2N2 and H3N2. SAP also inhibits the production of haemagglutinin (HA) an the cytopathogenic effect of influenza A virus in MDCK cells. The binding of SAP to the virus requires physiological calcium concentrations and is blocked by specific SAP antibodies. Denaturated and renaturated SAP retained inhibition of HA. Electron microscopy shows Ca(2+)-dependent binding of SAP to spikes on the viral envelope and immunoblotting indicates that SAP binds to a 50-55 kDa peptide corresponding to the mass of the HA1 peptide. Of several monosaccharides tested only D-mannose interfered with SAP's inhibition of both HA and infectivity. The glycosaminoglycans heparan sulfate and heparin, which bind SAP, reduced SAPs binding to the virus. The results indicate that the inhibition by SAP is due to steric effects when SAP binds to terminal mannose on oligosaccharides localized close to the sialic acid-binding site of the HA trimer.

Acetylgalactosamine↗
PubMed1997

Unemployment and cancer in Denmark, 1970-1975 and 1986-1990.

We have analysed cancer mortality and cancer incidence among unemployed persons identified from the Danish linkage studies based on the 1970 census and the 1986 register-based census. In 1970, 1% of Danish men were unemployed; in 1986, 14% were unemployed. In both periods, unemployed men had an excess cancer mortality of close to 25% when they were followed-up for a five-year period and their mortality was compared with that of all men in the labour force. Unemployed women in the 1970 cohort also had an excess cancer mortality of 25%. Cancer incidence data were not available for the 1986 cohort. For both cohorts, the excess risk came mainly from lung cancer. Survey data from Denmark in the 1980s indicated that unemployed men had a slightly higher smoking prevalence before unemployment than men who continued working, and that unemployment did not increase smoking. It is therefore unlikely that the excess lung cancer risk among unemployed men is explained by differences in smoking habits alone.

Adult↗
PubMed1996

[Infections in connection with epidural catheterization].

Seventy-eight patients with culture-positive epidural catheters were studied. Fifty-nine had symptoms of exit site infection and 11 patients had clinical meningitis, two of whom also had en epidural abscess. This corresponds to a local infection incidence of at least 4.3% and an incidence of central nervous system infection of at least 0.7% at Odense University Hospital. The patients with generalized symptoms of infection had been catheterized for a longer time, and were older than patients with only local symptoms of infection. The microorganisms isolated from the epidural catheters were coagulase- negative staphylococci (41%), Staphylococcus aureus (35%), Gram-negative bacilli (14%) and other bacteria (10%). The Gram-negative bacilli and S. aureus caused serious infections more frequently than the others. We discuss the symptoms and diagnosis of spinal epidural abscess and propose prophylactic and diagnostic guidelines for epidural catheter-related infections.

Adult↗
PubMed1996

Occupation and ischemic heart disease in the European Community: a comparative study of occupations at potential high risk.

Four longitudinal studies of mortality and morbidity by occupation based on individual record linkage of information and two cross-sectional studies of mortality were compared in order to identify occupations at high risk of ischemic heart disease. In more than one country an increased risk of ischemic heart disease was found in drivers of buses, taxies, and lorries, in bakers, in naval officers and fishermen, in hotel and restaurant workers, in senior police, customs, and other uniformed men, in barbers and hairdressers, in warehouse and wholesale staff, as well as in laboratory assistants and in radio and telegraph operators. Occupations found at high risk in Denmark were also found at high risk in Great Britain and Italy. These occupations may be at genuine high risk. None of these groups work day-work only and several of the groups have psychologically demanding work but unsatisfactory decision authority. Identification of occupations at high risk may help to develop focused preventive strategies.

Adolescent↗
PubMed1996

Acyclovir treatment of relapsing-remitting multiple sclerosis. A randomized, placebo-controlled, double-blind study.

Acyclovir treatment was used in a randomized, double-blind, placebo-controlled clinical trial with parallel groups to test the hypothesis that herpes virus infections are involved in the pathogenesis of multiple sclerosis (MS). Sixty patients with the relapsing-remitting form of MS were randomized to either oral treatment with 800 mg acyclovir or placebo tablets three times daily for 2 years. The clinical effect was investigated by an extensive test battery consisting of neurological examinations, neuro-ophthalmological and neuropsychological tests, and evoked potentials. Results were based on "intent-to-treat" data and the primary outcome measure was the exacerbation rate. In the acyclovir group (n = 30), 62 exacerbations were recorded during the treatment period, yielding an annual exacerbation rate of 1.03. The placebo group (n = 30) had 94 exacerbations and an annual exacerbation rate of 1.57. Thus, 34% fewer exacerbations were encountered during acyclovir treatment. This difference in exacerbation rate between the treatment groups was not significant (P = 0.083). However, this trend to a lower disease activity in acyclovir-treated patients was supported in subsequent data analysis. If the patients were grouped according to exacerbation frequencies, i.e. into low (0-2), medium (3-5) and high (6-8) rate groups, the difference between acyclovir and placebo treatment was significant (P = 0.017). Moreover, in a subgroup of the population with a duration of the disease of at least 2 years providing an exacerbation rate base-line before entry, individual differences in exacerbation rates were compared between the 2-year pre-study period and the study period in acyclovir-treated (n = 19) and placebo (n = 20) patients and acyclovir-treated patients showed a significant reduction of exacerbations (P = 0.024). Otherwise, neurological parameters were essentially unaffected by acyclovir treatment and there were no convincing signs of reduced neurological deterioration in the acyclovir group. This study indicates that acyclovir treatment might inhibit the triggering of MS exacerbations and thus suggests that acyclovir-susceptible viruses might be involved in the pathogenesis of MS. This possibility warrants further investigation.

Acyclovir↗
PubMed1996

Referral bias among health workers in studies using hospitalization as a proxy measure of the underlying incidence rate.

Contacts with health services like hospitals or general practitioners are usually the only available proxy measure of incidence of disease in studies based on secondary data and differential referrals or care-seeking behavior often bias such proxy measures. In former analyses based on the Occupational Hospitalization Register in Denmark assisting nurses had high Standardized Hospitalization Ratios for many diseases. It was, however, suspected that it fully or partly was due to a referral bias or self-selection to hospital treatment rather than exposures to occupational hazards. The aim of the present study is to evaluate the referral bias hypothesis by comparing hospitalization and mortality data for health workers for a disease category with a high mortality. Cohorts of all gainfully employed 20- to 59-year-old Danes were formed in order to compare Standardized Mortality Ratios and Standardized Hospitalization Ratios of ischemic heart disease (IHD) in occupational groups. The follow-up period was 10 years. For most of the investigated occupational groups a similar disease pattern was found whether hospitalization or death was used as the outcome measure. In "nurse assistants" a statistically significant higher risk was, however, found using hospitalization due to IHD as the end point rather than mortality. Additional analysis did not support the hypothesis that the finding could be explained by differentiated hospitalization due to social factors. The true incidence rates of the disease need not be equally well described by proxy measures such as hospitalization diagnosis or death diagnosis in all occupational groups. Differential access to medical treatment in some groups may lead to bias when hospital data are used as proxy measures for the underlying incidence rates.

Bias↗
PubMed1996

Binding of complement proteins C1q and C4bp to serum amyloid P component (SAP) in solid contra liquid phase.

Serum amyloid P component (SAP), a member of the conserved pentraxin family of plasma proteins, binds calcium dependently to its ligands. The authors investigated SAPs interaction with the complement proteins C4b binding protein (C4bp) and C1q by ELISA, immunoelectrophoresis and electron microscopy. Binding of these proteins to SAP was demonstrated when SAP was immobilized using F(ab')2 anti-SAP, but not when SAP reacted with these proteins in liquid phase; thus the binding to human SAP was markedly phase state dependent. Presaturation of solid phase SAP with heparin, which binds SAP with high affinity, did not interfere with the subsequent binding of C4bp or C1q to SAP. In contrast, collagen I and IV showed partial competition with the binding of C1q to SAP. Using fresh serum, immobilized native SAP bound C4bp whereas binding of C1q/C1 could not be demonstrated. Altogether the results indicate that firm binding of C1q and C4bp to SAP requires that SAP is presented on a solid phase, that C1q and C4bp react with sites distinct from the heparin binding site, and that C1q and collagen I share binding sites on SAP. Immobilized native SAP, aggregated SAP and SAP-heparansulphate complexes induced no detectable complement activation.

Animals↗
PubMed1996

Isolation and characterization of porcine mannan-binding proteins of different size and ultrastructure.

The authors report on the purification and characterization of mannan- binding proteins (MBP) isolated from porcine serum. The MBPs were purified by use of PEG precipitation, affinity chromatography on mannan-Sepharose, protein A- and anti-porcine IgM-Sepharose followed by gel filtration. The MBP proteins were collagenase sensitive and showed gamma 1-gamma 2-electrophoretic mobility. The MBP designated pMBP-28 had a molecular mass of 28 kDa when analysed on SDS-PAGE under reducing conditions and eluted corresponding to a molecular mass of approximately 700 kDa on gel filtration chromatography. Electron micrographs of pMBP-28 revealed an oligomeric protein similar to rodent MBP-A and human MBP but with a predominance of penta- and hexameric molecules. Another protein designated pMBP-27 was composed of peptides of 27 kDa and had an Mr of 300-350 kDa on gel filtration chromatography. Electron microscopy of pMBP-27 showed dimer and trimer molecules; the trimers without distinct stalk regions. The N-terminal 26(pMBP-27) and 24(MBP-28) amino acid residues showed 54% and 58% identity with human MBP.pMBP-28 showed a higher degree of sequence similarity to rat and mouse MBP-A (60% identity) than to mouse and rat MBP-C (41-45% identity). Both pMBPs exhibited Ca2+-dependent binding to D-mannose immobilized on agarose but no significant binding to N-acetyl-D-glucosamine- or fucose-agarose. The results further suggested the presence of a third pMBP which copurified with pMBP-27 but this protein was not sequenced.

Amino Acid Sequence↗
PubMed1996

Dietary fibres reduce blood pressure, serum total cholesterol and platelet aggregation in rats.

The effects of dietary fat and dietary fibres on blood pressure, serum lipids and platelet aggregation in spontaneously hypertensive and Wistar-Kyoto rats have been investigated. The systolic and diastolic blood pressure values were increased with increasing amounts of dietary fat and normalized by dietary fibre supplementation. The greatest reduction in blood pressure was obtained by a combination of reduced dietary fat and supplementary dietary fibre. Addition of dietary fibre when the amount of dietary fat was high or reduction of dietary fat when the amount of dietary fibre was low gave a smaller effect. In both rat strains the decreases in systolic and diastolic blood pressure values after reducing dietary fat and/or increasing dietary fibre were about 10-15 mmHg. Serum total cholesterol and serum HDL-cholesterol concentrations were reduced by reduction of dietary fat or a combination of dietary fat reduction and dietary fibre addition. A combination of dietary fat reduction and dietary fibre addition was the most effective dietary change for reducing serum triacylglycerol concentration and platelet aggregation. The present study demonstrates that in this experimental model it is possible to reduce risk indicators of coronary heart disease significantly by changing dietary habits.

Animals↗
PubMed1996

Elimination of recently absorbed methyl mercury depends on age and gender.

The toxicokinetics of some toxic metals have been demonstrated to depend on the age of the exposed individuals. Most studies focused solely upon age-dependent differences in degree of absorption. The present study aimed at investigating possible age-dependent differences in elimination of CH3HgCl using 203Hg and repeated whole-body counting of live mice to quantitate the whole-body retention. With increasing age at the time of exposure to a single oral dose of CH3HgCl, the rate of elimination more than doubled in male mice. As intestinal absorption of CH3HgCl is almost complete, the findings must pertain either to an age-related increased excretion capacity or an age-dependent change in the excretion mechanism. To study whether saturation of the excretion mechanism could explain this observation, groups at different age were supplemented with non-labeled CH3HgCl in the drinking water during a two weeks observation period after administration of a single dose of CH3203HgCl. Supplementation did not influence the rate of elimination of CH3HgCl in mature males. Accordingly, the mechanism causing the observed age-dependent change in elimination rate is not a matter of saturation but an age-dependent development of a more efficient mechanism for CH3HgCl elimination. Further, as elimination of mercury absorbed during a prolonged period of exposure through drinking water was not influenced by age, the critical step for the age-dependent mechanism for elimination of CH3HgCl seems to be the initial absorption and distributional phase after exposure and most likely involves the hepatic handling of methyl mercury.

Absorption↗
PubMed1996

Linomide reduces the rate of active lesions in relapsing-remitting multiple sclerosis.

The synthetic immunomodulator Linomide, a quinoline-3-carboxamide, has a profound inhibitory influence in several experimental autoimmune diseases, including acute and chronic experimental allergic encephalomyelitis. In a double-blind trial, 31 patients with relapsing-remitting multiple sclerosis were randomized to oral doses of 2.5 mg Linomide or placebo once a day for six months. Fourteen patients receiving Linomide and 14 receiving placebo completed the trial, and the results were based on this population. The mean number of active (new and enlarged T2 weighted) lesions per monthly MRI scan was 1.37 in the patients receiving Linomide and 4.22 in the patients receiving placebo (p = 0.043). The percentage of scans with active MRI lesions was lower in the Linomide-treated group (p = 0.0064). When neurologic deficit was assessed by the Regional Functional Scoring System (RFSS), the Linomide group showed an improvement of 1% of the maximal RFSS range and the placebo group a deterioration of 0.2% (p = 0.14). There were three patients with relapses in the Linomide-treated group and six in the placebo group (p = 0.22). A slightly decreased proportion of natural killer cells in cerebrospinal fluid and peripheral blood was noted in the Linomide group. A severe adverse event of pleuropericarditis occurred in one of the Linomide-treated patients. The most frequent adverse event was musculoskeletal pain, of mild to severe degree, which tended to diminish after three months on Linomide therapy.

Adjuvants, Immunologic↗
PubMed1996

Apparent water permeability as a physiological parameter in crustaceans

This article reviews the use of apparent water permeability (AWP) calculated from measurements of isotope-labelled water flux as a physiological estimate of whole-body water permeability in aquatic invertebrates. The rationale and practices of AWP calculations are described in an Appendix. AWP calculations have provided a wealth of information. However, the validity of the method and therefore also of the information obtained have been questioned. Consequently, the use of AWP data in discussions of osmotic and fluid homeostatic questions in aquatic invertebrates is limited. This article reviews three decades of published experiments in which measurements of isotope-labelled water fluxes were used to estimate water permeability in aquatic invertebrates. Data on 24 species of arthropod, most of them decapod crustaceans, are presented. The combined data indicate that the results obtained by different investigators on the same species show good agreement, even though different tracers and experimental methods have been applied. When available, results from other kinds of studies were used to evaluate the results obtained using the AWP measurements. The various results demonstrate that AWP is influenced not only by natural environmental factors, such as salinity and temperature, and by anthropogenic factors, such as potentially toxic trace metals, but that it is also regulated by intrinsic factors, such as ecdysis and life cycle stage. The results obtained can often be explained as effects of components of the habitat of the animal. Accordingly, studies on variations in AWP contribute to our understanding of the different physiological strategies used by species living in a changing environment. We conclude that calculations of AWP offer reliable, relevant physiological data in a range of crustacean species, as long as methodological limitations and uncertainties are kept in mind. In addition, we propose some possible new ways of applying AWP calculations to marine invertebrates other than crustaceans. A major part of this review describes results already obtained for the shore crab Carcinus maenas as this species is probably the animal on which most work has been carried out. We suggest topics for future work on this species and review the possibility of using AWP in C. maenas as a biomarker of metal exposure.

Journal Article↗
PubMed1996

Variation in risk indicators of cardiovascular disease during the menstrual cycle: an investigation of within-subject variations in glutathione peroxidase, haemostatic variables, lipids and lipoproteins in healthy young women.

Variations in erythrocyte glutathione peroxidase activity, serum concentrations of lipids and lipoproteins and in blood coagulation and fibrinolysis during the menstrual cycle were studied in healthy young women. Blood samples were drawn twice a week for 9 weeks. A group of males was used for estimation of the influence on the results of factors which were not related to the menstrual cycle. Variations during the menstrual cycle were demonstrated in several of the factors analysed. The activity of glutathione peroxidase was lowest at ovulation. The clotting activity of factor II+ VII+X and the concentration of fibrinogen were lowest during mid-cycle, and the number of platelets increased in the follicular phase (days 5-9). Statistically significant variations in the fibrinolytic factors analysed (tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) were not observed during the menstrual cycle. The serum concentrations of cholesterol and LDL cholesterol were significantly higher at the start of the menstrual cycle (days 3-8) than later in the cycle (days 19-24). The concentration of HDL cholesterol was lowest in the late luteal phase (days 23-28).

Adult↗
PubMed1995

[Problems when swallowing tablets. A questionnaire study from general practice].

Dysphagia, or difficulty in swallowing tablets, may greatly affect compliance. This report presents the results of our survey, which was undertaken to determine the proportion of a general practitioner's patient population who had difficulty in swallowing tablets, and to identify the reasons for the difficulty. 6,158 questionnaires were received from patients who consulted a general practitioner. More than 1/4 (26%) of the total patient population (or 1,576) said they had problems in swallowing tablets. A prominent complaint was the size of the tablet, followed by the surface, form and taste of the tablet. Twice as many women as men experienced swallowing problems. Elderly patients (> 70 years) had less difficulty than younger patients when taking tablets. To achieve good compliance and optimal pharmacotherapy, it is important for medical practitioners and pharmaceutical personnel to be aware of the general problems connected to swallowing tablets, to enable them to select the correctly formulated drug for their patients. New and novel oral drug formulations, such as tablets that dissolve in seconds on the tongue without water, may alleviate the problem of swallowing tablets. They offer substantial advantages over ordinary tablets, are more convenient to administer, and enhance the potential for improved compliance in patients who experience difficulty in taking tablets.

Adolescent↗
PubMed1995

Zinc and manganese bioavailability from human milk and infant formula used for very low birthweight infants, evaluated in a rat pup model.

The bioavailability of zinc and manganese from diets used for very low birthweight infants was investigated in a rat pup model using radioisotopes. The effect of protein source and content and of pasteurization was evaluated, and two different approaches for evaluation of zinc and manganese bioavailability from the studied human milk and infant formula for very low birthweight infants was high. Liver uptake of 65Zn from labeled premature infant diets in sucklings rat pups was 26-29%, and absorption calculated as the difference between administered dose and nonabsorbed activity 6 h after oral intubation was 93-95%. Retention of manganese calculated as the sum of 54Mn retained by organs and carcass was 85-95% from human milk and premature infant formula, and absorption calculated from nonabsorbed activity was 83-88% after 6 h. Fortification of early human milk significantly increased the bioavailability of zinc. No effect of pasteurization of human milk was found on zinc or manganese bioavailability. Liver zinc uptake was found to be a more sensitive parameter than absorption for evaluation of diets with a high zinc bioavailability. Measurement of retained activity of manganese in carcass and organs was judged to be the preferred parameter for evaluation of diets with high manganese availability.

Absorption↗