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1.
Proc Biol Sci ; 284(1859)2017 Jul 26.
Article in English | MEDLINE | ID: mdl-28724727

ABSTRACT

Trophic cascades occur in many ecosystems, but the factors regulating them are still elusive. We suggest that an overlooked factor is that trophic interactions (TIs) are often scale-dependent and possibly interact across spatial scales. To explore the role of spatial scale for trophic cascades, and particularly the occurrence of cross-scale interactions (CSIs), we collected and analysed food-web data from 139 stations across 32 bays in the Baltic Sea. We found evidence of a four-level trophic cascade linking TIs across two spatial scales: at bay scale, piscivores (perch and pike) controlled mesopredators (three-spined stickleback), which in turn negatively affected epifaunal grazers. At station scale (within bays), grazers on average suppressed epiphytic algae, and indirectly benefitted habitat-forming vegetation. Moreover, the direction and strength of the grazer-algae relationship at station scale depended on the piscivore biomass at bay scale, indicating a cross-scale interaction effect, potentially caused by a shift in grazer assemblage composition. In summary, the trophic cascade from piscivores to algae appears to involve TIs that occur at, but also interact across, different spatial scales. Considering scale-dependence in general, and CSIs in particular, could therefore enhance our understanding of trophic cascades.


Subject(s)
Ecosystem , Fishes , Food Chain , Animals , Bays , Biomass , Predatory Behavior , Sweden
2.
Scand J Rheumatol ; 46(1): 1-10, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27172254

ABSTRACT

OBJECTIVES: Heterophilic antibodies, such as rheumatoid factor (RF), are known to interfere with enzyme-linked immunosorbent assays (ELISAs). Treatment of rheumatoid arthritis (RA) with tumour necrosis factor (TNF)-α blockers is well established. The aims of this study were to develop a protocol for blocking the interaction of present heterophilic antibodies and to validate this procedure by evaluating the effect on correlations of cytokine levels to clinical response in RA patients treated with adalimumab. METHOD: Fourteen patients with active RA were evaluated at baseline and 3 months after starting adalimumab treatment. Cytokines were analysed with a commercial 12-plex bead ELISA. To block interference by RF, a commercial blocker (HeteroBlock) was used. To determine the optimal concentration of HeteroBlock, patient sera were analysed with different concentrations of HeteroBlock. Subsequently, baseline and follow-up sera from the 14 patients were analysed and correlated with clinical outcome. RESULTS: Measured cytokine levels were reduced in the majority of samples when adding the blocker. The optimal concentration of HeteroBlock was 1600 µg/mL of serum. Sera with high RF levels were more prone to produce false positive values, although some RF-negative sera also demonstrated evidence of interference. HeteroBlock did not interfere with the analysis. In RA patients treated with adalimumab, changes in interleukin (IL)-6 levels between baseline and follow-up correlated with changes in erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in sera with added HeteroBlock. CONCLUSIONS: When analysing sera from patients with RA with multiplex bead ELISA, the assay should be evaluated for interference by heterophilic antibodies, and if present corrected with, for example, HeteroBlock.


Subject(s)
Arthritis, Rheumatoid/blood , Arthritis, Rheumatoid/immunology , Cytokines/blood , Enzyme-Linked Immunosorbent Assay/methods , Rheumatoid Factor , Adalimumab/therapeutic use , Aged , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care/methods
3.
J Fish Biol ; 83(4): 939-62, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24090556

ABSTRACT

In March 2006, a 360 km² no-take zone (NTZ) was established north of Gotland in the central Baltic Sea, with the purpose to scientifically evaluate the effects of a fishing ban on flatfish populations. A monitoring programme was set up to study the populations in the NTZ and in a reference area east of Gotland where the fishing pressure was high. The programme included fishing with multimesh survey nets, modelling of potential larval export and estimation of fish consumption by large marine predators. Overall, the results showed a clear positive effect of the NTZ on turbot Scophthalmus maximus, with higher densities in the closed area compared with the fished area and also higher densities after closure compared with before. The NTZ also had older individuals and a more even sex ratio. This, in combination with a high potential for larval export from the NTZ to Gotland, shows that the marine reserve may be important for maintaining a viable S. maximus stock at Gotland. Also, for flounder Platichthys flesus, the densities were higher in the NTZ compared to the reference area and there was a net larval export to the fished area. For both species, density-dependent growth was evident, with a lower length at age in the closed area. Potential predation by grey seal Halichoerus grypus and great cormorant Phalacrocorax carbo sinesis on flatfishes, that could hamper the evaluation of the marine reserve, was also addressed. Taken together, the results show that there are clear benefits of the fishing ban for both flatfish species within the NTZ, while the net effects on fisheries are difficult to quantify.


Subject(s)
Conservation of Natural Resources/methods , Fisheries/methods , Flatfishes , Animals , Ecosystem , Female , Larva , Male , Oceans and Seas , Population Dynamics , Sex Ratio , Sweden
4.
Osteoporos Int ; 24(2): 533-40, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22525983

ABSTRACT

SUMMARY: Middle-aged women with active commuting had significantly lower risk for wrist fracture than women commuting by car/bus. INTRODUCTION: Our purpose was to investigate whether a physically active lifestyle in middle-aged women was associated with a reduced risk of later sustaining a low-trauma wrist fracture. METHODS: The Umeå Fracture and Osteoporosis (UFO) study is a population-based nested case-control study investigating associations between lifestyle and fragility fractures. From a cohort of ~35,000 subjects, we identified 376 female wrist fracture cases who had reported data regarding their commuting habits, occupational, and leisure physical activity, before they sustained their fracture. Each fracture case was compared with at least one control drawn from the same cohort and matched for age and week of reporting data, yielding a total of 778 subjects. Mean age at baseline was 54.3 ± 5.8 years, and mean age at fracture was 60.3 ± 5.8 years. RESULTS: Conditional logistic regression analysis with adjustments for height, body mass index, smoking, and menopausal status showed that subjects with active commuting (especially walking) were at significantly lower risk of sustaining a wrist fracture (OR 0.48; 95 % CI 0.27-0.88) compared with those who commuted by car or bus. Leisure time activities such as dancing and snow shoveling were also associated with a lower fracture risk, whereas occupational activity, training, and leisure walking or cycling were unrelated to fracture risk. CONCLUSION: This study suggests that active commuting is associated with a lower wrist fracture risk, in middle-aged women.


Subject(s)
Osteoporotic Fractures/prevention & control , Transportation/methods , Wrist Injuries/prevention & control , Aged, 80 and over , Case-Control Studies , Exercise/physiology , Female , Humans , Life Style , Middle Aged , Motor Activity/physiology , Osteoporotic Fractures/epidemiology , Osteoporotic Fractures/physiopathology , Risk Factors , Seasons , Sweden/epidemiology , Wrist Injuries/epidemiology , Wrist Injuries/physiopathology
5.
Scand J Rheumatol ; 42(2): 123-30, 2013.
Article in English | MEDLINE | ID: mdl-23126587

ABSTRACT

OBJECTIVE: Suggested predictors of rheumatoid arthritis (RA) include environmental exposure, such as smoking. Our purpose was to investigate potential predictors of RA in a nested case-control study based on a prospective cohort. METHOD: Between 1991 and 1996, 30,447 persons were included in the Malmö Diet and Cancer Study (MDCS). Individuals who developed RA after inclusion up to 31 December 2004 were identified by linking the database to different registers. Four controls were selected for every case. Data on lifestyle factors were collected in the MDCS. RESULTS: We identified 172 incident cases of RA [36 men/136 women, mean age at diagnosis 63 years, 69% rheumatoid factor (RF) positive, median time from inclusion to diagnosis 5 (range 1-13) years]. In bivariate analyses, baseline smoking [odds ratio (OR) 2.02, 95% confidence interval (CI) 1.31-3.12] and a low level of formal education (i.e. ≤ 8 years; OR 2.42, 95% CI 1.18-4.93 vs. University degree) predicted subsequent development of RA. Infrequent baseline alcohol consumption was a predictor of RA (OR 3.47, 95% CI 1.91-6.30) compared to recent use (within the past month), and individuals with moderate baseline alcohol consumption (3.5-15.2 g/day vs. < 3.5 g/day) tended to have a reduced risk of RA (OR 0.48, 95% CI 0.22-1.05) in multivariate analyses, adjusted for smoking and level of education. CONCLUSIONS: Smoking and a low level of formal education were found to be independent predictors of RA. Moderate alcohol consumption may also be associated with a reduced risk.


Subject(s)
Alcohol Drinking/adverse effects , Arthritis, Rheumatoid/epidemiology , Educational Status , Smoking/adverse effects , Aged , Case-Control Studies , Cohort Studies , Female , Humans , Incidence , Male , Middle Aged , Prospective Studies , Risk Factors
6.
Osteoporos Int ; 24(5): 1587-98, 2013 May.
Article in English | MEDLINE | ID: mdl-23085859

ABSTRACT

UNLABELLED: Prevention of hip fractures is of critical public health importance. In a cohort of adults from eight European countries, evidence was found that increased adherence to Mediterranean diet, measured by a 10-unit dietary score, is associated with reduced hip fracture incidence, particularly among men. INTRODUCTION: Evidence on the role of dietary patterns on hip fracture incidence is scarce. We explored the association of adherence to Mediterranean diet (MD) with hip fracture incidence in a cohort from eight European countries. METHODS: A total of 188,795 eligible participants (48,814 men and 139,981 women) in the European Prospective Investigation into Cancer and nutrition study with mean age 48.6 years (±10.8) were followed for a median of 9 years, and 802 incident hip fractures were recorded. Diet was assessed at baseline through validated dietary instruments. Adherence to MD was evaluated by a MD score (MDs), on a 10-point scale, in which monounsaturated were substituted with unsaturated lipids. Association with hip fracture incidence was assessed through Cox regression with adjustment for potential confounders. RESULTS: Increased adherence to MD was associated with a 7 % decrease in hip fracture incidence [hazard ratio (HR) per 1-unit increase in the MDs 0.93; 95 % confidence interval (95 % CI) = 0.89-0.98]. This association was more evident among men and somewhat stronger among older individuals. Using increments close to one standard deviation of daily intake, in the overall sample, high vegetable (HR = 0.86; 95 % CI = 0.79-0.94) and high fruit (HR = 0.89; 95 % CI = 0.82-0.97) intake was associated with decreased hip fracture incidence, whereas high meat intake (HR = 1.18; 95 % CI = 1.06-1.31) with increased incidence. Excessive ethanol consumption (HR high versus moderate = 1.74; 95 % CI = 1.32-2.31) was also a risk factor. CONCLUSIONS: In a prospective study of adults, increased adherence to MD appears to protect against hip fracture occurrence, particularly among men.


Subject(s)
Diet, Mediterranean/statistics & numerical data , Hip Fractures/epidemiology , Adult , Age Factors , Aged , Cohort Studies , Europe/epidemiology , Feeding Behavior , Female , Hip Fractures/prevention & control , Humans , Incidence , Life Style , Male , Middle Aged , Prospective Studies , Sex Factors
7.
Reprod Toxicol ; 30(4): 558-65, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20656018

ABSTRACT

Exposure of rodents in utero to perfluorooctane sulfonate (PFOS) impairs perinatal development and survival. Following intravenous or gavage exposure of C57Bl/6 mouse dams on gestational day (GD) 16 to (35)S-PFOS (12.5mg/kg), we determined the distribution in dams, fetuses (GD18 and GD20) and pups (postnatal day 1, PND1) employing whole-body autoradiography and liquid scintillation counting. In dams, levels were highest in liver and lungs. After placental transfer, (35)S-PFOS was present on GD18 at 2-3 times higher levels in lungs, liver and kidneys than in maternal blood. In PND1 pups, levels in lungs were significantly higher than in GD18 fetuses. A heterogeneous distribution of (35)S-PFOS was observed in brains of fetuses and pups, with levels higher than in maternal brain. This first demonstration of substantial localization of PFOS to both perinatal and adult lungs is consistent with evidence describing the lung as a target for the toxicity of PFOS at these ages.


Subject(s)
Alkanesulfonic Acids/pharmacokinetics , Environmental Pollutants/pharmacokinetics , Fluorocarbons/pharmacokinetics , Maternal Exposure , Maternal-Fetal Exchange , Alkanesulfonic Acids/blood , Animals , Animals, Newborn/blood , Animals, Newborn/metabolism , Brain/metabolism , Environmental Pollutants/blood , Female , Fetal Blood/chemistry , Fetus/metabolism , Fluorocarbons/blood , Kidney/metabolism , Liver/metabolism , Lung/metabolism , Mice , Mice, Inbred C57BL , Pregnancy , Scintillation Counting , Sulfur Radioisotopes , Tissue Distribution , Whole Body Imaging
8.
Allergy ; 64(6): 919-26, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19183417

ABSTRACT

BACKGROUND: Defined particles carrying tightly bound allergens at high density have been suggested as alternatives in allergy vaccination. Carbohydrate based particles (CBP), sized 2 microm, provide a platform for covalent coupling of allergens. OBJECTIVE: To investigate the mechanisms of antigen presentation by CBP, as well as cellular and humoral responses after vaccination with the major cat allergen Fel d 1, covalently coupled to CBP. METHODS: Mice (n = 10/group) were subcutaneously vaccinated with CBP-rFel d 1, CBP or phosphate buffer saline (PBS) before sensitization with rFel d 1 and challenged with cat dander extract. Fluorescent and (75)Se-radiolabeled tracking of allergens and particles were performed with flow cytometry and whole-body autoradiography. Humoral, cellular and regulatory immune responses were analyzed by ELISA and flow cytometry. Cytokines were measured in bronchoalveolar lavage fluid and splenocyte cultures. RESULTS: CBP-rFel d 1 prevented induction of airway inflammation and induced allergen-specific T-cell anergy. CBP-rFel d 1 also induced rapid IgM and IgG1-responses compared with soluble rFel d 1. Particles were phagocytosed by antigen-presenting cells and transported to draining lymph nodes and spleen. Moreover, antigen coupled to CBP remained longer at the injection site compared with alum. CONCLUSIONS: Covalent coupling of rFel d 1 to CBP induces rapid antibody production, prevents induction of allergic immune responses and systemic allergen spreading. Thus, CBP comprise several attractive adjuvant features for use in allergy vaccination. CLINICAL IMPLICATIONS: Prolonged allergen exposure through covalent coupling to particles suitable for phagocytosis, provides an adjuvant for safer and efficient allergy vaccination.


Subject(s)
Adjuvants, Immunologic/administration & dosage , Carbohydrates/administration & dosage , Glycoproteins/administration & dosage , Hypersensitivity/prevention & control , Vaccination , Animals , CD11c Antigen/analysis , Female , Glycoproteins/immunology , Immunoglobulin G/blood , Mice , Mice, Inbred BALB C , Phagocytosis , T-Lymphocytes/immunology
9.
Ann Rheum Dis ; 68(4): 526-30, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18477739

ABSTRACT

OBJECTIVE: To determine whether breast feeding or the use of oral contraceptives (OCs) affects the future risk of rheumatoid arthritis (RA) in a community-based prospective cohort. METHODS: A community-based health survey (18 326 women) was linked to regional and national registers, and incident cases of RA were identified. All women with a diagnosis of RA after inclusion in the health survey (n = 136) and four female controls for every case, who were alive and free from RA when the index person was given a diagnosis of RA, were included in a case-control study. Data on lifestyle factors at baseline were derived from a self-administered questionnaire. Potential predictors were examined in logistic regression models. RESULTS: 136 women with incident RA were compared with 544 age-matched controls. A longer history of breast feeding was associated with a reduced risk of RA (OR 0.46 (95% CI 0.24 to 0.91) for women who had breast fed for >/=13 months and OR 0.74 (95% CI 0.45 to 1.20) for those who had breast fed for 1-12 months, compared with those who had never breast fed). The protective effect of longer breast feeding remained significant after adjustment for smoking and level of education in multivariate models, and point estimates were protective also when the analyses were restricted to parous women. Neither parity nor OC use had any significant effect on the risk of RA. CONCLUSION: In this study, long-term breast feeding, but not OC use, was associated with a significant reduction in the risk of RA.


Subject(s)
Arthritis, Rheumatoid/prevention & control , Breast Feeding , Contraceptives, Oral , Adult , Aged , Case-Control Studies , Female , Humans , Logistic Models , Longitudinal Studies , Multivariate Analysis , Pregnancy , Risk
10.
Osteoporos Int ; 19(9): 1267-73, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18214568

ABSTRACT

UNLABELLED: In a study of a 12-year population-based injury register, Umeå, Sweden, we analyzed the fracture mechanisms and fracture pattern in men and women 50 years and older. Low-energy trauma was responsible for the major and costliest part of the fracture panorama, but the pattern differs between age groups. INTRODUCTION: Osteoporosis-related fracture is a major health problem: the number of hip fractures is expected to double to 2030. While osteoporosis is one of many risk factors, trauma is almost always involved. Therefore, we analyzed injury mechanisms in patients aged over 50. METHODS: We registered injury mechanism, cause, diagnosis in all trauma patients at Umeå University hospital, Sweden. This population-based register (1993-2004) comprises a total of 113,668 injuries (29,189 fractures). Patients >or=50 years contributed to 13,279 fractures. RESULTS: Low-energy trauma (fall <1 m) caused 53% of all fractures >or=50 years and older. In those over 75 low-energy trauma caused >80%. The seasonal variation of fractures was maximally 25%. With increasing age, proximal fractures became more common, in both upper and lower extremities. Proximal locations predominate in older age groups. CONCLUSIONS: Low-energy trauma was responsible for the largest and costliest part of the fracture panorama. In fact, almost all fractures in middle-aged and old people were caused by low-energy mechanisms; thus, most fractures in these patients have a fragility component, and the contribution of osteoporosis-related fractures is more important than previously thought. A better understanding of injury mechanisms also in low-energy trauma is a prerequisite for preventive interventions.


Subject(s)
Fractures, Bone/etiology , Accidental Falls/statistics & numerical data , Accidents, Home/statistics & numerical data , Age Distribution , Aged , Aged, 80 and over , Female , Fractures, Bone/epidemiology , Fractures, Bone/pathology , Humans , Incidence , Lower Extremity/injuries , Male , Middle Aged , Osteoporosis/complications , Osteoporosis/epidemiology , Registries , Seasons , Sweden/epidemiology , Upper Extremity/injuries
11.
Neurotoxicology ; 28(6): 1120-8, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17655932

ABSTRACT

2,6-Dichlorophenyl methylsulphone and a number of structurally related chemicals are CYP-activated toxicants in the olfactory mucosa in mice and rats. This toxicity involves both the olfactory neuroepithelium and its subepithelial nerves. In addition, 2,6-dichlorophenyl methylsulphone induces glial acidic fibrillary protein expression (Gfap, a biomarker for gliosis) in the olfactory bulb, as well as long-lasting learning deficits and changes in spontaneous behavior in mice and rats. So far the 2,5-dichlorinated isomer has not been reported to cause toxicity in the olfactory system, although it gives rise to transient changes in spontaneous behavior. In the present study we used 15k cDNA gene arrays and real-time RT-PCR to determine 2,6-dichlorophenyl methylsulphone-induced effects on gene expression in the olfactory bulb in mice. Seven days following a single ip dose of 2,6-dichlorophenyl methylsulphone, 56 genes were found to be differentially expressed in the olfactory bulb. Forty-one of these genes clustered into specific processes regulating, for instance, cell differentiation, cell migration and apoptosis. The genes selected for real-time RT-PCR were chosen to cover the range of B-values in the cDNA array analysis. Altered expression of Gfap, mt-Rnr2, Ncor1 and Olfml3 was confirmed. The expression of these genes was measured also in mice dosed with 2,5-dichlorophenyl methylsulphone, and mt-Rnr2 and Olfml3 were found to be altered also by this isomer. Combined with previous data, the results support the possibility that the persistent neurotoxicity induced by 2,6-dichlorophenyl methylsulphone in mice represents both an indirect and a direct effect on the brain. The 2,5-dichlorinated isomer, negative with regard to CYP-catalyzed toxicity in the olfactory mucosa, may prove useful to resolve this issue.


Subject(s)
Benzene Derivatives/toxicity , Gene Expression Profiling , Gene Expression/drug effects , Olfactory Bulb/drug effects , Olfactory Mucosa/drug effects , Sulfones/toxicity , Animals , Benzene Derivatives/administration & dosage , Cluster Analysis , Female , Gene Expression Profiling/methods , Glial Fibrillary Acidic Protein/genetics , Glial Fibrillary Acidic Protein/metabolism , Glycoproteins/genetics , Glycoproteins/metabolism , Injections, Intraperitoneal , Isomerism , Mice , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Nuclear Receptor Co-Repressor 1 , Olfactory Bulb/metabolism , Olfactory Bulb/pathology , Olfactory Mucosa/metabolism , Olfactory Mucosa/pathology , Oligonucleotide Array Sequence Analysis , Polymerase Chain Reaction , RNA, Messenger/metabolism , Repressor Proteins/genetics , Repressor Proteins/metabolism , Sulfones/administration & dosage , Time Factors
12.
Scand J Rheumatol ; 36(3): 179-83, 2007.
Article in English | MEDLINE | ID: mdl-17657670

ABSTRACT

OBJECTIVE: We sought to investigate the cost of living with rheumatoid arthritis (RA) and evaluate the influence of both demographics and specific disease characteristics on these costs. METHODS: We used a population-based questionnaire to survey 895 patients living in the city of Malmö, Sweden, during 2002. Data were obtained on direct resource consumption, investments, informal care and work capacity, as well as utility, function and patients' assessment of disease severity and pain. RESULTS: The survey was completed by 613 patients (68%). Their mean age was 66 years, 74% were female and the mean duration of disease was 16.7 years. The total mean annual cost per patient was 108,370 SEK (12,020 EUR). Direct costs represented 41% of that amount and were predominantly for drugs [14% of the participants were receiving treatment with tumour necrosis factor (TNF) blockers], community services and hospitalisation. Function measured with the Health Assessment Questionnaire (HAQ) was the main statistical predictor for all types of costs except sick leave, which was most strongly associated with patients' perception of global health. CONCLUSION: This is the first study in Sweden to include all costs incurred by a group representative of RA in the community. In comparison with previous studies, total costs had increased by more than 40%. Furthermore, direct costs were higher and constituted a great proportion of total costs because of more intensive treatments (i.e. the use of TNF blockers). Future comparisons will enable health economic evaluations on a community level.


Subject(s)
Arthritis, Rheumatoid/economics , Cost of Illness , Aged , Arthritis, Rheumatoid/drug therapy , Female , Health Care Costs , Humans , Male , Multivariate Analysis , Tumor Necrosis Factor-alpha/antagonists & inhibitors
13.
J Radiol Prot ; 26(2): 161-87, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16738414

ABSTRACT

The BIOMOSA (BIOsphere MOdels for Safety Assessment of radioactive waste disposal) project was part of the EC fifth framework research programme. The main goal of this project was to improve the scientific basis for the application of biosphere models in the framework of long-term safety studies of radioactive waste disposal facilities and to enhance the confidence in using biosphere models for performance assessments. The study focused on the development and application of a generic biosphere tool BIOGEM (BIOsphere GEneric Model) using the IAEA BIOMASS reference biosphere methodology, and the comparison between BIOGEM and five site-specific biosphere models. The site-specific models and the generic model were applied to five typical locations in Europe, resulting in estimates of the annual effective individual doses to the critical groups and the ranking of the importance of the exposure pathways for each of the sites. Uncertainty in the results was also estimated by means of stochastic calculations based on variation of the site-specific parameter values. This paper describes the generic model and the deterministic and stochastic results obtained when it was applied to the five sites. Details of the site-specific models and the corresponding results are described in two companion papers. This paper also presents a comparison of the results between the generic model and site-specific models. In general, there was an acceptable agreement of the BIOGEM for both the deterministic and stochastic results with the results from the site-specific models.


Subject(s)
Ecosystem , Models, Biological , Radiation Monitoring/methods , Radioactive Pollutants/analysis , Risk Assessment/methods , Body Burden , Computer Simulation , Europe , Radiation Dosage , Relative Biological Effectiveness , Risk Factors
14.
J Radiol Prot ; 25(4): 375-91, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16340067

ABSTRACT

In the framework of the BioMoSA project for the development of biosphere assessment models for radioactive waste disposal the Reference Biosphere Methodology developed in the IAEA programme BIOMASS was applied to five locations, situated in different European countries. Specific biosphere models were applied to assess the hypothetical contamination of a range of agricultural and environmental pathways and the dose to individuals, following contamination of well water. The results of these site-specific models developed by the different BioMoSA partners, and the individual normalised dose to the exposure groups were compared against each other. Ingestion of drinking water, fruit and vegetables were found to be among the most important pathways for almost all radionuclides. Stochastic calculations revealed that consumption habits, transfer factors, irrigation rates and distribution coefficients (Kd(s)) were the most important parameters that influence the end results. Variations in the confidence intervals were found to be higher for sorbing elements (e.g. (36)Cl, (237)Np, (99)Tc, (238)U, (129)I) than for mobile elements (e.g. (226)Ra, (79)Se, (135)Cs, (231)Pa, (239)Pu). The influence of daughter products, for which the distribution into the biosphere was calculated individually, was also shown to be important. This paper gives a brief overview of the deterministic and stochastic modelling results and the parameter sensitivity. A screening methodology was introduced to identify the most important pathways, simplify a generic biosphere tool and refine the existing models.


Subject(s)
Models, Theoretical , Radioactive Waste , Radiometry/methods , Refuse Disposal/methods , Water Pollutants, Radioactive/analysis , Water Supply , Adult , Environmental Exposure , Europe , Humans , Infant , Monte Carlo Method , Refuse Disposal/standards , Risk Assessment
15.
J Radiol Prot ; 25(4): 343-73, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16352869

ABSTRACT

This paper describes the development and application of site-specific biosphere models that might be used for assessment of potential exposures in the framework of performance assessment studies of nuclear waste disposals. Model development follows the Reference Biosphere Methodology that has been set up in the framework of the BIOMASS study. In this paper, the application is to real sites at five European locations for which environmental and agricultural conditions have been described and characterised. For each of the sites a biosphere model has been developed specifically assuming a release of radionuclides to waters that are used by humans, for example as drinking water for humans and cattle and as irrigation water. Among the ingestion pathways, the intakes of drinking water, cereals, leafy vegetables, potatoes, milk, beef and freshwater fish are included in all models. Annual individual doses were calculated, and uncertainties in the results were estimated by means of stochastic calculations. To enable a comparison, all results were normalised to an activity concentration in groundwater of 1 Bq m(-3) for each of the radionuclides considered ((36)Cl, (79)Se, (99)Tc, (129)I, (135)Cs, (226)Ra, (231)Pa, (230)Th, (237)Np, (239)Pu, and (238)U), i.e. those that are usually most relevant in performance assessment studies of nuclear waste disposals. Although the results do not give answers in absolute terms on potential future exposures, they indicate the spectrum of exposures that might occur in different environments and specify the interaction of environmental conditions, human habits and potential exposure.


Subject(s)
Environmental Exposure/standards , Radioactive Waste , Radiometry/methods , Refuse Disposal/methods , Animals , Europe , Food Contamination/prevention & control , Humans , Risk Assessment , Soil Pollutants, Radioactive/standards , Water Pollution, Radioactive
16.
J Vet Pharmacol Ther ; 26(3): 205-11, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12755905

ABSTRACT

Xylazine is an alpha2-adrenoceptor agonist sedative with a much higher interspecies variability in effect than detomidine, another alpha2-agonist used in veterinary practice. In the present study, we have used radioligand binding in brain tissue to investigate if the high species variation in sensitivity to xylazine could be explained in terms of receptor interactions. Species known to be more (cattle) or less (swine and rats) sensitive to xylazine were used. There was no variation in the density or the subtype pattern of the alpha2-adrenoceptors that could explain the species variation recorded in vivo, as a homogenous population of the alpha2A/D-subtype (200-300 fmol/mg protein) was found in all species. The species differences in the affinities of xylazine and detomidine were minor and similar for the two drugs. The only parameter investigated where a significant species difference was found for xylazine but not for detomidine was the slope of the inhibition binding curve when the G-protein coupling was diminished. For xylazine this slope was considerably lower than unity (i.e. 0.77 +/- 0.075) using cattle preparations compared with 0.92 +/- 0.037 (mean +/- SE) and 0.90 +/- 0.028, respectively for swine and rats, while for detomidine this parameter was close to unity in all species (cattle, swine, rat). This finding indicates that the species variation in effect for xylazine could be due to differences at the G-protein level or further down-stream in the effect cascade.


Subject(s)
Adrenergic alpha-Agonists/pharmacology , Brain/drug effects , Imidazoles/pharmacology , Receptors, Adrenergic, alpha-2/drug effects , Xylazine/pharmacology , Adrenergic alpha-Agonists/administration & dosage , Animals , Brain/metabolism , Brain Stem/drug effects , Brain Stem/metabolism , Cattle/metabolism , Dose-Response Relationship, Drug , Female , Imidazoles/administration & dosage , Male , Radioligand Assay/veterinary , Rats/metabolism , Species Specificity , Swine/metabolism , Xylazine/administration & dosage
17.
J Drug Target ; 10(6): 469-78, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12575737

ABSTRACT

Picolinic acid (PA) protects against quinolinic acid- and kainic acid-induced neurotoxicity in the brain. To study the uptake of PA to the brain, we administered [3H]PA via a unilateral nasal instillation or iv injection to mice. Autoradiography demonstrated a rapid uptake of radioactivity in the olfactory nerve layer and in the ipsilateral olfactory bulb (OB) following nasal instillation of [3H]PA. After 4 h, there was a high level of radioactivity in the central parts of the ipsilateral OB and olfactory peduncle. Moreover, iv injection of [3H]PA demonstrated a selective uptake and retention of radioactivity in the OB. Gas chromatography-mass spectrometry (GC-MS) demonstrated the presence of PA and PA-glycine conjugate in the OB. In mice with reduced peripheral olfactory innervations there was a decreased uptake of [3H]PA in the OB as compared to controls suggesting that an intact olfactory neuroepithelium is a prerequisite for an uptake of PA to the OB. There is an increased interest in brain targeting of drugs with limited ability to pass the blood-brain barrier. The present results demonstrate that PA fulfils structural requirements for a transfer along the olfactory pathways to the brain.


Subject(s)
Brain/metabolism , Drug Delivery Systems/methods , Olfactory Pathways/metabolism , Picolinic Acids/administration & dosage , Administration, Intranasal , Animals , Brain/drug effects , Female , Injections, Intravenous , Mice , Olfactory Pathways/drug effects , Picolinic Acids/pharmacokinetics
18.
Scand J Rheumatol ; 29(6): 358-64, 2000.
Article in English | MEDLINE | ID: mdl-11132204

ABSTRACT

OBJECTIVE: To identify clinical and genetic risk factors for extra-articular manifestations of rheumatoid arthritis (ExRA). METHODS: ExRA patients were identified retrospectively using predefined criteria in two hospital-based cohorts of RA patients, and compared to non-extraarticular RA controls from one of the cohorts, matched for disease duration. RESULTS: Forty-nine living and thirteen deceased cases of ExRA were identified. Extra-articular disease was predicted by the demonstration of antinuclear antibodies (Odds ratio (OR) 3.6; 95% CI: 1.4-9.1) and the presence of rheumatoid nodules within two years from RA diagnosis (OR 3.4; 95%, CI: 1.1-10.9) or at any time before ExRA onset (OR 2.8; 95% CI: 1.1-7.2). Male sex and rheumatoid factor did not affect the risk of ExRA. Although present in the majority of cases as well as controls, the disease associated HLA-DRB1 subtypes were not significant predictors of ExRA. CONCLUSION: Extra-articular manifestations of rheumatoid arthritis in a hospital based population were predicted by antinuclear antibodies and rheumatoid nodules.


Subject(s)
Arthritis, Rheumatoid/complications , Rheumatoid Nodule/etiology , Adolescent , Adult , Antibodies, Antinuclear/analysis , Arthritis, Rheumatoid/immunology , Child , Cohort Studies , Female , HLA-DR Antigens/analysis , HLA-DRB1 Chains , Humans , Male , Middle Aged , Prognosis , Retrospective Studies
19.
Rheumatology (Oxford) ; 38(7): 668-74, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10461483

ABSTRACT

OBJECTIVE: The prevalence and distribution of extra-articular manifestations of rheumatoid arthritis (ExRA) and associated mortality were studied retrospectively in a cohort of RA patients admitted to University Hospital, Malmö, Sweden, during the period 1990-94. RESULTS: Of 489 patients who fulfilled the 1987 ACR criteria for RA, 37 manifested onset of ExRA, predominantly serositis and cutaneous vasculitis, during the period, corresponding to a cumulative incidence of 7.9%. The occurrence of ExRA was independent of disease stage. Among patients with ExRA, 1 death/4.3 person-years at risk (pyr) occurred, as compared with 1 death/11.4 pyr in the non-ExRA subgroup. The age- and sex-adjusted mortality rate ratio was 2.49 (95% confidence interval 1.43-4.03). The major cause of death among ExRA cases was heart disease, which occurred in 9/13 cases (69%) in comparison to the expected 2.4 cases. CONCLUSION: In this series, serositis and cutaneous vasculitis were predominant extra-articular manifestations of RA; and mortality was greater in the ExRA than in the non-ExRA subgroup, perhaps due to a high frequency of associated heart disease.


Subject(s)
Arthritis, Rheumatoid/complications , Cardiovascular Diseases/epidemiology , Serositis/epidemiology , Vasculitis/epidemiology , Adolescent , Adult , Aged , Arthritis, Rheumatoid/mortality , Cardiovascular Diseases/etiology , Cause of Death , Cohort Studies , Comorbidity , Female , Humans , Male , Middle Aged , Prevalence , Retrospective Studies , Serositis/etiology , Sweden/epidemiology , Vasculitis/etiology
20.
Scand J Rheumatol ; 28(3): 160-5, 1999.
Article in English | MEDLINE | ID: mdl-10380838

ABSTRACT

The aim of this study was to evaluate differences in disease activity, disability, and medical treatment in consecutive patients with rheumatoid arthritis seen at the outpatient clinics in Malmö, in 1978 (n = 148) and 1995 (n = 164). The groups were similar with regard to age, gender, disease duration, and the proportion having had hip or knee replacement surgery. The patients in 1995 had lower values for CRP (p<0.001), Ritchie Articular Index (mean values: 5.5 vs. 9.9, p<0.001), and Steinbrocker functional class index (mean values: 1.96 vs. 2.16, p<0.001) than the 1978 group. The 1995 patient group was also more extensively treated with DMARD:s (68 vs. 51%, p<0.01) and glucocorticosteroids (23 vs. 12%, p<0.02) and had historically been treated with almost twice as many DMARD:s (2.7 vs. 1.5, p<0.001). Similar findings regarding disease activity and disability were made when restricting the analysis to subgroups of patients that were seropositive or had a shorter disease duration (< 5 yrs). The lower disease severity in the 1995 group may be secondary to a more active medical treatment, although other possibilities such as differences in selection and secular changes in disease severity unrelated to medication cannot be excluded.


Subject(s)
Arthritis, Rheumatoid/physiopathology , Adult , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/blood , Arthritis, Rheumatoid/drug therapy , Cohort Studies , Disability Evaluation , Female , Humans , Male , Middle Aged , Rheumatoid Factor/blood
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