88 results on '"Hansen EW"'
Search Results
2. Introduction of a Novel Self-Injector for Sumatriptan. A Controlled Clinical Trial in General Practice
- Author
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Jensen, K, Tfelt-Hansen, P, Hansen, EW, Krøis, EH, and Pedersen, OS
- Abstract
A novel self-injector for the administration of subcutaneous sumatriptan in the treatment of migraine attacks was tested in 138 patients recruited by family physicians in Denmark; 108 patients completed the initial double-blind, crossover part of the study. Sumatriptan 6 mg s.c. was significantly better than placebo at 30, 60, 90 and 120 min after injection in relieving moderate or severe headache to mild or none as well as relieving any headache to none. At 60 min after injection, the treatment response rate was 61% for sumatriptan and 6% for placebo. During the following open-phase trial of four attacks treated with sumatriptan, treatment response rates were 68–74%. During the total of 538 attacks treated, 12 attempts at using the self-injector failed. In the double-blind and open phases, 81% and 90% of patients respectively found the device easy or very easy to use. Adverse effects were benign and short-lasting, but led seven patients to discontinue the study. In conclusion, subcutaneous sumatriptan administered with a novel self-injector is an effective treatment for migraine compared to placebo in patients treated by their family physician.
- Published
- 1995
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3. Endocannabinoid mediates excitatory synaptic function of β-Neurexins
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Hansen eWang
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Alzheimer Disease ,autism ,LTP ,synaptic plasticity ,neural circuits ,endocannabinoid ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Published
- 2016
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4. Autism spectrum disorders: emerging mechanisms and mechanism-based treatment
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Hansen eWang and Laurie eDoering
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Fragile X Syndrome ,Rett Syndrome ,MeCP2 ,Pathogenesis ,Autism Spectrum Disorders ,Treatment ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Published
- 2015
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5. Targeted pharmacological treatment of autism spectrum disorders: fragile X and Rett syndromes
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Hansen eWang, Sandipan ePati, Lucas ePozzo-Miller, and Laurie eDoering
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Dopamine ,Fragile X Syndrome ,Minocycline ,Oxytocin ,Pharmacology ,Rett Syndrome ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Autism spectrum disorders (ASDs) are genetically and clinically heterogeneous and lack effective medications to treat their core symptoms. Studies of syndromic ASDs caused by single gene mutations have provided insights into the pathophysiology of autism. Fragile X and Rett syndromes belong to the syndromic ASDs in which preclinical studies have identified rational targets for drug therapies focused on correcting underlying neural dysfunction. These preclinical discoveries are increasingly translating into exciting human clinical trials. Since there are significant molecular and neurobiological overlaps among ASDs, targeted treatments developed for fragile X and Rett syndromes may be helpful for autism of different etiologies. Here, we review the targeted pharmacological treatment of fragile X and Rett syndromes and discuss related issues in both preclinical studies and clinical trials of potential therapies for the diseases.
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- 2015
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6. Fragile X mental retardation protein: from autism to neurodegenerative disease
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Hansen eWang
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Alzheimer Disease ,Fragile X Syndrome ,Neurodegenerative Diseases ,autism ,prion protein ,synaptic plasticity ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Published
- 2015
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7. Lipid rafts: a signaling platform linking cholesterol metabolism to synaptic deficits in autism spectrum disorders
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Hansen eWang
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Cholesterol ,Fragile X Syndrome ,Rett Syndrome ,MeCP2 ,Statins ,synaptic plasticity ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Published
- 2014
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8. Reversing autism by targeting downstream mTOR signaling
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Hansen eWang and Laurie C. Doering
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Cognition ,Fragile X Syndrome ,Learning ,Memory ,Neurofibromatosis 1 ,Rett Syndrome ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Published
- 2013
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9. Group I metabotropic glutamate receptor-mediated gene transcription and implications for synaptic plasticity and diseases
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Hansen eWang and Min eZhuo
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Fragile X Syndrome ,Signal Transduction ,LTP ,Mouse ,synaptic plasticity ,LTD ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Stimulation of group I metabotropic glutamate receptors (mGluRs) initiates a wide variety of signaling pathways. Group I mGluR activation can regulate gene expression at both translational and transcriptional levels, and induces translation or transcription dependent synaptic plastic changes in neurons. The group I mGluR-mediated translation-dependent neural plasticity has been well reviewed. In this review, we will highlight group I mGluR-induced gene transcription and its role in synaptic plasticity. The signalling pathways (PKA, CaMKs and MAPKs) which have been shown to link group I mGluRs to gene transcription, the relevant transcription factors (CREB and NF-κB) and target proteins (FMRP and ARC) will be documented. The significance and future direction for characterizing group I mGluR-mediated gene transcription in fragile X syndrome, schizophrenia, drug addiction and other neurological disorders will also be discussed.
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- 2012
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10. Response to correspondence by Johan Øvrevik.
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Frankel M, Madsen AM, and Hansen EW
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- Humans, Air Microbiology, Air Pollution, Indoor analysis, Construction Materials microbiology, Fungi growth & development, Particulate Matter immunology
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- 2014
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11. Exposure and preventive measure to reduce high and daily exposure to Bacillus thuringiensis in potted plant production.
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Madsen AM, Zervas A, Tendal K, Matthiesen CB, Koponen IK, and Hansen EW
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- Aerosols analysis, Female, Humans, Inhalation Exposure analysis, Male, Occupational Exposure prevention & control, Particle Size, Plants, Risk Assessment, Air Pollutants, Occupational analysis, Bacillus thuringiensis, Biological Control Agents, Environmental Monitoring methods, Inhalation Exposure prevention & control
- Abstract
The bacterium Bacillus thuringiensis (Bt) is the active organism in a variety of commercially available products used worldwide as biopesticides. Bt products are applied in large outdoor areas as well as in indoor environments. Even though it has been sold for decades, not much is known about the occupational exposure to Bt. The aim of this study was to obtain knowledge about the exposure to Bt subspecies israelensis (Bti) in a propagation section in a greenhouse, where Bti is applied hourly by a spray boom, and to test a preventive measure to reduce the exposure to airborne Bti. Furthermore, we wanted to study the exposure during work with potted plants treated earlier with Bti. Exposure to aerosols with Bti was measured repeatedly by personal and stationary samplers before and after the intervention. Bti was identified by polymerase chain reaction in air and soil samples. Personal exposure to inhalable Bti in the propagation section was 3×10(5) cfu m(-3) (median level, n = 22); the personal exposure of people working with plants treated earlier with Bti was 3200 cfu m(-3) (median level, n = 17). The highest single measure was found for the person working with the spray boom (7×10(5) cfu m(-3)) but airborne Bti was present at all sampling stations in the propagation section. Bti constituted a high share of the airborne cultivable bacteria and a smaller share of the soilborne bacteria in the propagation section. In a human cell assay, spiking an aerosol sample with a product with Bti increased the inflammatory potential of an aerosol sample from the greenhouse significantly. Based on the inflammatory potential and the high personal exposure, a cover around the spray boom was built as an attempt to reduce the daily exposure to Bti. The cover reduced the personal exposure to Bti from 3.0×10(5) cfu m(-3) to 1.8×10(4) cfu m(-3). The exposure was thus reduced by a factor 17, which is a considerable reduction. Bti was present in different particle size fractions with the majority, both before and after the intervention, in the fraction of airborne particles with an aerodynamic diameter between 1.2 and 3.0 µm. The measured occupational exposure to Bti is discussed in relation to risk evaluation., (© The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.)
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- 2014
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12. Effect of relative humidity on the aerosolization and total inflammatory potential of fungal particles from dust-inoculated gypsum boards.
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Frankel M, Hansen EW, and Madsen AM
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- Denmark, Fungi immunology, HL-60 Cells, Humans, Humidity, Seasons, beta-Glucans analysis, beta-Glucans immunology, Air Microbiology, Air Pollution, Indoor analysis, Construction Materials microbiology, Fungi growth & development, Particulate Matter immunology
- Abstract
The aim of this study was to investigate the effect of relative humidity (RH) on the aerosolization and total inflammatory potential (TIP) of microbial particles released from gypsum boards inoculated with dust samples from homes. After microbial colonization, the gypsum boards were incubated at either high or low RH. The aerosolized particles (0.54-19.8 μm), culturable fungi, β-glucan and the TIP of the aerosolized particles were quantified. Despite the colonization of several fungal groups, Penicillium dominated the aerosolized fraction. Higher emission rates of particles and culturable fungi were found from low RH compared with high RH in both the inhalable and particulate matter <1 μm (PM1 ) fractions, and the TIP was accordingly higher. However, for the aerosolized fractions, the TIP or concentration β-glucan relative to the number of fungi or particles present was higher from high RH compared with low RH. Despite the low number of culturable fungi in PM1 , this fraction showed a high TIP, and the concentration of β-glucan correlated strongly with the TIP of this fraction. The individual particles of the aerosolized PM1 fraction were more inflammatory than the larger particles of the inhalable fraction, and β-glucan may be an important contributor to the inflammatory potential of the aerosolized particles., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
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- 2014
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13. Considerations regarding use of solvents in in vitro cell based assays.
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Timm M, Saaby L, Moesby L, and Hansen EW
- Abstract
Cell culture systems are widely used for the investigation of in vitro immunomodulatory effects of medicines and natural products. Since many pharmacological relevant compounds are water-insoluble, solvents are frequently used in cell based assays. Although many reports describe the cellular effects of solvents at high concentrations, only a few relate the effects of solvents used at low concentrations. In this report we investigate the interference of three commonly used solvents: Dimethyl sulfoxide (DMSO), ethanol and β-cyclodextrin with five different cell culture systems. The effects of the solvents are investigated in relation to the cellular production of interleukin (IL)-6 or reactive oxygen species (ROS) after lipopolysaccharide (LPS) stimulation. We show that DMSO above 1 % reduces readout parameters in all cell types but more interestingly the 0.25 and 0.5 % solutions induce inhibitory effects in some cell types and stimulatory effects in others. We also found that LPS induced ROS production was more affected than the IL-6 production in the presence of ethanol. Finally we showed that β-cyclodextrin at the investigated concentrations did not have any effect on the LPS induced IL-6 production and only minor effects on the ROS production. We conclude that the effects induced by solvents even at low concentrations are highly relevant for the interpretation of immunomodulatory effects evaluated in cell assays. Furthermore, these results show the importance of keeping solvent concentrations constant in serial dilution of any compound investigated in cell based assays.
- Published
- 2013
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14. Comment on: Harte et al. High fat intake leads to acute postprandial exposure to circulating endotoxin in type 2 diabetic subjects. Diabetes Care 2012;35:375-382.
- Author
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Hansen HS, Moesby L, Timm M, and Hansen EW
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- Female, Humans, Male, Diabetes Mellitus, Type 2 blood, Diet, High-Fat adverse effects, Endotoxins blood
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- 2013
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15. Seasonal variations of indoor microbial exposures and their relation to temperature, relative humidity, and air exchange rate.
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Frankel M, Bekö G, Timm M, Gustavsen S, Hansen EW, and Madsen AM
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- Colony Count, Microbial, Denmark, Endotoxins analysis, Humidity, Particulate Matter isolation & purification, Temperature, Air Microbiology, Bacteria isolation & purification, Fungi isolation & purification, Seasons
- Abstract
Indoor microbial exposure has been related to adverse pulmonary health effects. Exposure assessment is not standardized, and various factors may affect the measured exposure. The aim of this study was to investigate the seasonal variation of selected microbial exposures and their associations with temperature, relative humidity, and air exchange rates in Danish homes. Airborne inhalable dust was sampled in five Danish homes throughout the four seasons of 1 year (indoors, n = 127; outdoors, n = 37). Measurements included culturable fungi and bacteria, endotoxin, N-acetyl-beta-d-glucosaminidase, total inflammatory potential, particles (0.75 to 15 μm), temperature, relative humidity, and air exchange rates. Significant seasonal variation was found for all indoor microbial exposures, excluding endotoxin. Indoor fungi peaked in summer (median, 235 CFU/m(3)) and were lowest in winter (median, 26 CFU/m(3)). Indoor bacteria peaked in spring (median, 2,165 CFU/m(3)) and were lowest in summer (median, 240 CFU/m(3)). Concentrations of fungi were predominately higher outdoors than indoors, whereas bacteria, endotoxin, and inhalable dust concentrations were highest indoors. Bacteria and endotoxin correlated with the mass of inhalable dust and number of particles. Temperature and air exchange rates were positively associated with fungi and N-acetyl-beta-d-glucosaminidase and negatively with bacteria and the total inflammatory potential. Although temperature, relative humidity, and air exchange rates were significantly associated with several indoor microbial exposures, they could not fully explain the observed seasonal variations when tested in a mixed statistical model. In conclusion, the season significantly affects indoor microbial exposures, which are influenced by temperature, relative humidity, and air exchange rates.
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- 2012
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16. Comparison of sampling methods for the assessment of indoor microbial exposure.
- Author
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Frankel M, Timm M, Hansen EW, and Madsen AM
- Subjects
- Bacteria isolation & purification, Endotoxins analysis, Fungi isolation & purification, Seasons, Statistics, Nonparametric, Air Microbiology, Air Pollution, Indoor analysis, Dust analysis
- Abstract
Unlabelled: Indoor microbial exposure has been related to allergy and respiratory disorders. However, the lack of standardized sampling methodology is problematic when investigating dose-response relationships between exposure and health effects. In this study, different sampling methods were compared regarding their assessment of microbial exposures, including culturable fungi and bacteria, endotoxin, as well as the total inflammatory potential (TIP) of dust samples from Danish homes. The Gesamtstaubprobenahme (GSP) filter sampler and BioSampler were used for sampling of airborne dust, whereas the dust fall collector (DFC), the electrostatic dust fall collector (EDC), and vacuum cleaner were used for sampling of settled dust. The GSP assessed significantly higher microbial levels than the BioSampler, yet measurements from both samplers correlated significantly. Considerably higher levels of fungi, endotoxin, and TIP were found in the EDC compared with the DFC, and regarding fungi, the EDC correlated more strongly and significantly with vacuumed dust than the DFC. Fungi in EDC and vacuum dust correlated most strongly with airborne dust, and in particular, the measurements from the EDC associated well with those from GSP. Settled dust from the EDC was most representative of airborne dust and may thus be considered as a surrogate for the assessment of indoor airborne microbial exposure., Practical Implications: Significant discrepancies between sampling methods regarding indoor microbial exposures have been revealed. This study thus facilitates comparison between methods and may therefore be used as a frame of reference when studying the literature or when conducting further studies on indoor microbial exposure. Results also imply that the relatively simple EDC method for the collection of settled dust may be used as an alternative to otherwise tedious and time-consuming airborne dust sampling., (© 2012 John Wiley & Sons A/S.)
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- 2012
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17. Immunomodulatory effects of testosterone evaluated in all-trans retinoic acid differentiated HL-60 cells, granulocytes, and monocytes.
- Author
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Boje A, Moesby L, Timm M, and Hansen EW
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- Adult, Cell Differentiation, Cells, Cultured, Granulocytes immunology, HL-60 Cells, Humans, Interleukin-8 immunology, Male, Monocytes immunology, Reactive Oxygen Species immunology, Tretinoin, Granulocytes drug effects, Immunologic Factors pharmacology, Monocytes drug effects, Testosterone pharmacology
- Abstract
The sex hormones are known to affect innate immunity in humans. In this study we evaluated the immunomodulatory effects of testosterone in a model system comprising of all-trans retinoic acid differentiated HL-60 cells, and confirmed the results in human granulocytes and monocytes. Results showed that testosterone at pharmacological doses reduced the production of interleukin-8 and reactive oxygen species from differentiated HL-60 cells in a concentration dependent manner without affecting phagocytosis. The cells were stimulated with zymosan, lipopolysaccharide, or Bacillus subtilis. At the highest concentration of testosterone (120 μM), interleukin-8 secretion was reduced 42-80%, and production of reactive oxygen species was reduced 32-46%. Flutamide, an antagonist of the classical intracellular androgen receptor, was unable to antagonize the immunosuppressive effect of testosterone. We further demonstrated that the suppressive effect of testosterone has a short onset time. Our results suggest that testosterone affects the fast operating membrane bound androgen receptor or a rapid acting enzyme system. Testosterone, at pharmacological doses, was also shown to suppress generation of reactive oxygen species and interleukin-8 in human granulocytes and monocytes, respectively, to a similar extent as observed in differentiated HL-60 cells., (Copyright © 2012 Elsevier B.V. All rights reserved.)
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- 2012
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18. Reduction of Sb(V) in a human macrophage cell line measured by HPLC-ICP-MS.
- Author
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Hansen C, Hansen EW, Hansen HR, Gammelgaard B, and Stürup S
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- Antimony analysis, Antiparasitic Agents analysis, Biotransformation, Cell Line, Chromatography, High Pressure Liquid, Chromatography, Ion Exchange, Culture Media, Humans, Macrophages chemistry, Mass Spectrometry, Oxidation-Reduction, Reactive Oxygen Species metabolism, Respiratory Burst drug effects, Antimony metabolism, Antimony Sodium Gluconate metabolism, Antiparasitic Agents metabolism, Macrophages metabolism
- Abstract
Drugs based on pentavalent antimony are first-line treatment of the parasite disease leishmaniasis. It is generally believed that Sb(V) acts as a prodrug, which is activated by reduction to Sb(III); however, the site of reduction is not known. It has been hypothesised that the reduction takes place in the parasites' host cells, the macrophages. In this study, the human macrophage cell line Mono Mac 6 was exposed to Sb(V) in form of the drug sodium stibogluconate (Pentostam™). Cell extracts were analysed for Sb species by high-performance liquid chromatography with inductively coupled plasma-mass spectrometry detection. We found that Sb(V) is actually reduced to Sb(III) in the macrophages; up to 23% of the intracellular Sb was found as Sb(III). Transfer of the cells to Sb-free medium rapidly decreased their Sb(V) and Sb(III) content. Induction of the cell's production of reactive oxygen species did not have any marked effect on the intracellular amounts of Sb(III).
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- 2011
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19. Adverse events following immunization in children: retrospective analysis of spontaneous reports over a decade.
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Aagaard L, Hansen EW, and Hansen EH
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- Adolescent, Age Factors, Child, Child, Preschool, Denmark, Female, Humans, Infant, Male, Retrospective Studies, Severity of Illness Index, Sex Factors, Time Factors, Vaccination methods, Vaccines administration & dosage, Adverse Drug Reaction Reporting Systems statistics & numerical data, Vaccination adverse effects, Vaccines adverse effects
- Abstract
Purpose: There is no doubt that paediatric immunization prevents serious diseases, but the administration of these vaccines to healthy children also involves risks of adverse drug reactions (ADRs), some of which are potentially serious. The current body of evidence on ADRs from immunization therapy at the population level is partly contradictory across countries, time periods and childhood immunization programmes. The objective of our study was to characterize reported adverse events (AEFIs) following immunization in Danish children., Methods: Adverse events (AEFIs) in 0- to 17-year-old children and adolescents reported to the Danish Medicines Agency (DKMA) between 1998 and 2007 were analysed. The unit of analysis was one AEFI. Data were categorized with respect to time, age, and gender of the children, suspected vaccines, category and seriousness of the AEFIs, and reporting rate., Results: During the study period, the DKMA received 1,365 reports covering 2,600 AEFIs, corresponding to 60% of all adverse events reported for children. One third of the AEFIs were classified as serious, and two deaths were reported. The annual number of serious AEFIs remained constant during the study period. Approximately 80% of AEFIs were reported in children aged 0-2 years. Of all reported AEs, 45% were in the category "general disorders and administration site conditions", followed by the categories "skin and subcutaneous tissue disorders" (20% of total AEFIs) and "nervous system disorders" (16% of total AEFIs). The largest share of serious events was from the category "nervous system disorders" (33% of serious AEFIs). The most frequently reported serious AEs were febrile convulsions, pyrexia, and injection-site reactions., Conclusions: In Denmark, a large number of AEFIs following paediatric immunization have been reported, but the majority of cases were non-serious.
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- 2011
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20. Isolation of immunomodulatory triterpene acids from a standardized rose hip powder (Rosa canina L.).
- Author
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Saaby L, Jäger AK, Moesby L, Hansen EW, and Christensen SB
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- Cell Line, Cell Survival, Humans, Immunologic Factors isolation & purification, Interleukin-6 metabolism, Oleanolic Acid isolation & purification, Pentacyclic Triterpenes, Triterpenes isolation & purification, Betulinic Acid, Ursolic Acid, Immunologic Factors pharmacology, Oleanolic Acid pharmacology, Plant Extracts pharmacology, Rosa chemistry, Triterpenes pharmacology
- Abstract
A previously published systematic review and a metaanalysis have concluded that the consumption of standardized rose hip powder (Rosa canina L.) can reduce pain in osteoarthritis patients. Synovial inflammation has been suggested to play an important role in the pathogenesis of osteoarthritis and mainly to involve infiltration of the synovial membrane by macrophages. Therefore, the immunomodulatory effect of standardized rose hip powder of Rosa canina L. was investigated and active principles isolated using the Mono Mac 6 cell line as a model for human macrophages. Treatment of Mono Mac 6 cells with the residue of a crude dichloromethane extract of rose hip powder significantly and concentration dependently inhibited the lipopolysaccharide induced interleukin-6 release. Through bioassay-guided fractionation the immunomodulatory effect of the dichloromethane extract was correlated to a mixture of three triterpene acids; oleanolic acid, betulinic acid and ursolic acid (IC(50) 21 ± 6 µm). Further studies revealed that only oleanolic acid and ursolic acid, but not betulinic acid, could inhibit the lipopolysaccharide induced interleukin-6 release from Mono Mac 6 cells when tested separately. Combination of either oleanolic acid or ursolic acid with betulinic acid enhanced the immunomodulatory effect of the two triterpene acids., (Copyright © 2010 John Wiley & Sons, Ltd.)
- Published
- 2011
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21. "The upper limits of vegetation on Mauna Loa, Hawaii": a 50th-anniversary reassessment.
- Author
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Juvik JO, Rodomsky BT, Price JP, Hansen EW, and Kueffer C
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- Climate Change, Demography, Geological Phenomena, Hawaii, Time Factors, Altitude, Ecosystem, Plants classification
- Abstract
In January 1958, a survey of alpine flora was conducted along a recently constructed access road across the upper volcanic slopes of Mauna Loa, Hawaii (2525-3397 m). Only five native Hawaiian species were encountered on sparsely vegetated historic and prehistoric lava flows adjacent to the roadway. A resurvey of roadside flora in 2008 yielded a more than fourfold increase to 22 species, including nine native species not previously recorded. Eight new alien species have now invaded this alpine environment, although exclusively limited to a few individuals in ruderal habitat along the roadway. Alternative explanations for species invasion and altitudinal change over the past 50 years are evaluated: (1) changes related to continuing primary succession on ameliorating (weathering) young lava substrates; (2) local climate change; and (3) road improvements and increased vehicular access which promote enhanced car-borne dispersal of alien species derived from the expanding pool of potential colonizers naturalized on the island in recent decades. Unlike alpine environments in temperate latitudes, the energy component (warming) in climate change on Mauna Loa does not appear to be the unequivocal driver of plant invasion and range extension. Warming may be offset by other climate change factors including rainfall and evapotranspiration.
- Published
- 2011
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22. Safety pharmacology, toxicology and pharmacokinetic assessment of human Gc globulin (vitamin D binding protein).
- Author
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Pihl TH, Jørgensen CS, Santoni-Rugiu E, Leifsson PS, Hansen EW, Laursen I, and Houen G
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- Animals, Dogs, Drug Evaluation, Preclinical, Drug Stability, Female, Guinea Pigs, HL-60 Cells, Horses blood, Human Umbilical Vein Endothelial Cells, Humans, Infusions, Intravenous, Injections, Intravenous, Male, Mice, Neovascularization, Physiologic drug effects, Organ Specificity, Rabbits, Rats, Species Specificity, Tissue Distribution, Toxicity Tests, Acute, Toxicity Tests, Chronic, Vitamin D-Binding Protein blood, Vitamin D-Binding Protein pharmacokinetics, Vitamin D-Binding Protein toxicity
- Abstract
Gc globulin is an important protein of the plasma actin-scavenger system. As such, it has been shown to bind free actin and prevent hypercoagulation and shock in patients with massive actin release resulting from severe tissue injuries. Treatment of such patients with Gc globulin could therefore potentially be life-saving. This article presents pre-clinical toxicology experiments conducted on purified plasma-derived human Gc globulin. The Gc globulin formulation was shown to be stable for at least 4 years with full retention of actin-binding capacity. In vitro studies did not reveal activation of the kallikrein system or the complement system and cellular studies showed no toxic effects on a variety of human cell lines. In vivo studies showed no acute toxic effects in mice, rats or guinea pigs upon intravenous infusion. A 14-day local tolerance study in rabbits showed no adverse effects, and 14-day toxicity studies in rats and horses did not show any unwanted reactions. In a 14-day toxicology study in beagle dogs, formation of antibodies was seen and in the end of the study period, three out of four dogs showed clinical immunological reactions, which could be ascribed to the formation of antibodies. The half-life, T, for human Gc globulin was 12 hr in rats, 16 hr in horses and 30 hr in dogs. The safety profile of plasma-derived Gc globulin is concluded to be consistent to that required for use in man., (© 2010 The Authors. Basic & Clinical Pharmacology & Toxicology © 2010 Nordic Pharmacological Society.)
- Published
- 2010
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23. Direct interaction between CD91 and C1q.
- Author
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Duus K, Hansen EW, Tacnet P, Frachet P, Arlaud GJ, Thielens NM, and Houen G
- Subjects
- Antigens, CD immunology, Calreticulin metabolism, Complement C1q immunology, Enzyme-Linked Immunosorbent Assay, Humans, Leukocytes, Mononuclear immunology, Leukocytes, Mononuclear metabolism, Ligands, Low Density Lipoprotein Receptor-Related Protein-1, Protein Binding, Surface Plasmon Resonance, Time Factors, Antigens, CD metabolism, Complement C1q metabolism
- Abstract
C1q-mediated removal of immune complexes and apoptotic cells plays an important role in tissue homeostasis and the prevention of autoimmune conditions. It has been suggested that C1q mediates phagocytosis of apoptotic cells through a receptor complex assembled from CD91 (alpha-2- macroglobulin receptor, or low-density lipoprotein receptor-related protein) and calreticulin, with CD91 being the transmembrane part and calreticulin acting as the C1q-binding molecule. In the present study, we observe that C1q binds cells from a CD91 expressing monocytic cell line as well as monocytes from human blood. C1q binding to monocytes was shown to be correlated with CD91 expression and could be inhibited by the CD91 chaperone, receptor-associated protein. We also report data showing a direct interaction between CD91 and C1q. The interaction was investigated using various protein interaction assays. A direct interaction between purified C1q and CD91 was observed both by ELISA and a surface plasmon resonance assay, with either C1q or CD91 immobilized. The interaction showed characteristics of specificity because it was time-dependent, saturable and could be inhibited by known ligands of both CD91 and C1q. The results obtained show for the first time that CD91 recognizes C1q directly. On the basis of these findings, we propose that CD91 is a receptor for C1q and that this multifunctional scavenger receptor uses a subset of its ligand-binding sites for clearance of C1q and C1q bound material.
- Published
- 2010
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24. Assessment of the total inflammatory potential of bioaerosols by using a granulocyte assay.
- Author
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Timm M, Madsen AM, Hansen JV, Moesby L, and Hansen EW
- Subjects
- Acetylglucosaminidase analysis, Air Pollution, Indoor analysis, Biological Assay, Colony Count, Microbial, Endotoxins analysis, Environmental Monitoring, Granulocytes immunology, Inhalation Exposure analysis, Occupational Exposure analysis, beta-Glucans analysis, Aerosols analysis, Air Microbiology, Bacteria isolation & purification, Biofuels, Fungi isolation & purification
- Abstract
Occupational health symptoms related to bioaerosol exposure have been observed in a variety of working environments. Bioaerosols contain microorganisms and microbial components. The aim of this study was to estimate the total inflammatory potential (TIP) of bioaerosols using an in vitro assay based on granulocyte-like cells. A total of 129 bioaerosol samples were collected in the breathing zone of workers during their daily working routine at 22 biofuel plants. The samples were analyzed by traditional assays for dust, endotoxin, fungal spores, (1-->3)-beta-d-glucan, total number of bacteria, the enzyme N-acetyl-beta-d-glucosaminidase (NAGase; primarily originating from fungi), Aspergillus fumigatus, and mesophilic and thermophilic actinomycetes; the samples were also assayed for TIP. In a multilinear regression four factors were significant for the TIP values obtained: endotoxin (P < 0.0001), fungal spores (P < 0.0001), (1-->3)-beta-d-glucan (P = 0.0005), and mesophilic actinomycetes (P = 0.0063). Using this model to estimate TIP values on the basis of microbial composition, the correlation to the measured values was r = 0.91. When TIP values obtained in the granulocyte assay were related to the primary working area, we found that bioaerosol samples from personnel working in straw storage facilities showed high TIP values ( approximately 50 times the TIP of unstimulated controls). In contrast, bioaerosol samples from personnel with work functions in offices or laboratories showed low TIP values ( approximately 5 times the TIP of the unstimulated control). This indicates, as expected, that these areas were less contaminated. In conclusion, the granulocyte assay reacts to multiple contaminants in the environmental samples and can be used to obtain a measurement of TIP. Therefore, potential occupational health effects related to inflammation of the airways in a working environment can be estimated using this assay.
- Published
- 2009
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25. Nanoparticle temperature estimation in combined ac and dc magnetic fields.
- Author
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Rauwerdink AM, Hansen EW, and Weaver JB
- Subjects
- Calibration, Magnetics, Nanoparticles, Temperature
- Abstract
The harmonics produced by the nonlinear magnetization of superparamagnetic nanoparticles have been utilized in a number of budding medical devices. Here we expand on an earlier technique for quantitatively measuring nanoparticle temperature in a purely ac field by including the presence of a static field. The ability to quantify nanoparticle temperature by tracking changes in the 4th/2nd harmonic ratio is presented and shown to achieve an accuracy of 0.79 K. The advantage of even harmonics, issues with odd harmonics in the presence of a static field and the potential for future incorporation into an imaging system are discussed.
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- 2009
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26. MCF-7 human mammary adenocarcinoma cells exhibit augmented responses to human insulin on a collagen IV surface.
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Listov-Saabye N, Jensen MB, Kiehr B, Hansen EW, Svendsen JE, Lundby A, Holm GM, and Oleksiewicz MB
- Subjects
- Adenocarcinoma pathology, Animals, Breast Neoplasms pathology, Cell Line, Tumor, Collagen Type IV pharmacology, Dose-Response Relationship, Drug, Estradiol metabolism, Female, Humans, Hypoglycemic Agents metabolism, Hypoglycemic Agents pharmacology, Insulin analogs & derivatives, Insulin pharmacology, Lethal Dose 50, Mice, Mitogens metabolism, Mitosis, Reference Standards, Reproducibility of Results, Thymidine metabolism, Adenocarcinoma metabolism, Breast Neoplasms metabolism, Collagen Type IV metabolism, Insulin metabolism
- Abstract
Human mammary cell lines are extensively used for preclinical safety assessment of insulin analogs. However, it is essentially unknown how mitogenic responses can be optimized in mammary cell-based systems. We developed an insulin mitogenicity assay in MCF-7 human mammary adenocarcinoma cells, under low serum (0.1% FCS) and phenol red-free conditions, with 3H thymidine incorporation as endpoint. Based on EC50 values determined from 10-fold dilution series, beta-estradiol was the most potent mitogen, followed by human IGF-1, human AspB10 insulin and native human insulin. AspB10 insulin was significantly more mitogenic than native insulin, validating the ability of the assay to identify hypermitogenic human insulin analogs. With MCF-7 cells on a collagen IV surface, the ranking of mitogens was maintained, but fold mitogenic responses and dynamic range and steepness of dose-response curves were increased. Also, PI3K pathway activation by insulin was enhanced on a collagen IV surface. This study provided the first determination and ranking of the mitogenic potencies of standard reference compounds in an optimized MCF-7 assay. The optimized MCF-7 assay described here is of relevance for in vitro toxicological testing and carcinogenicity safety assessment of new insulin compounds., (Copyright 2009 John Wiley & Sons, Ltd.)
- Published
- 2009
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27. Magnetic nanoparticle temperature estimation.
- Author
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Weaver JB, Rauwerdink AM, and Hansen EW
- Subjects
- Computer-Aided Design, Equipment Design, Equipment Failure Analysis, Nanomedicine methods, Nanoparticles radiation effects, Reproducibility of Results, Sensitivity and Specificity, Temperature, Thermography methods, Magnetics instrumentation, Nanomedicine instrumentation, Nanoparticles chemistry, Thermography instrumentation
- Abstract
The authors present a method of measuring the temperature of magnetic nanoparticles that can be adapted to provide in vivo temperature maps. Many of the minimally invasive therapies that promise to reduce health care costs and improve patient outcomes heat tissue to very specific temperatures to be effective. Measurements are required because physiological cooling, primarily blood flow, makes the temperature difficult to predict a priori. The ratio of the fifth and third harmonics of the magnetization generated by magnetic nanoparticles in a sinusoidal field is used to generate a calibration curve and to subsequently estimate the temperature. The calibration curve is obtained by varying the amplitude of the sinusoidal field. The temperature can then be estimated from any subsequent measurement of the ratio. The accuracy was 0.3 degree K between 20 and 50 degrees C using the current apparatus and half-second measurements. The method is independent of nanoparticle concentration and nanoparticle size distribution.
- Published
- 2009
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28. Cryopreservation of differentiated HL-60 cells for pyrogen testing.
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Timm M, Bartelt S, Moesby L, and Hansen EW
- Subjects
- Antineoplastic Agents pharmacology, Dose-Response Relationship, Drug, HL-60 Cells, Humans, Neutrophils cytology, Pyrogens immunology, Pyrogens pharmacology, Reactive Oxygen Species analysis, Reactive Oxygen Species immunology, Sensitivity and Specificity, Tretinoin pharmacology, Biological Assay methods, Cell Differentiation drug effects, Cryopreservation, Neutrophils immunology, Pyrogens analysis
- Abstract
All-trans retinoic-acid (ATRA) differentiated HL-60 cells can be used to detect pyrogens such as bacteria, bacterial components, yeasts and fungi. Differentiated HL-60 cells obtain neutrophil like characteristics and if stimulated the differentiated HL-60 cells produce reactive oxygen species in a dose dependent manner. Culturing and differentiation of cell lines are time consuming activities and require suitable facilities; cryopreservation of pre-differentiated cells could provide the basis for an easily distributable pyrogen testing kit. Cryopreservation of granulocytes has proven to be very complicated and neutrophils are especially difficult to cryopreserve, most likely due to their large degree of granulation. Here we present evidence that HL-60 cells can be differentiated with ATRA and subsequently cryopreserved. Upon thawing the cells retain their ROS producing capabilities and reactivity towards pyrogens. Further, the cells retain their ability to react dose dependently towards lipopolysaccharide (LPS), lipoteichoic acid (LTA) and zymosan. At pathophysiologically relevant concentrations of LPS, LTA and zymosan the cells retain full reactivity for at least two months when stored in liquid nitrogen. In conclusion, ATRA differentiated HL-60 cells are cryopreservable and retain reactivity upon thawing. It is therefore possible to produce an in-vitro in-house pyrogen test kit for medicines and related products.
- Published
- 2008
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29. Effect of moist heat sterilisation on the pyrogenicity of cell wall components from Staphylococcus aureus.
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Moesby L, Timm M, and Hansen EW
- Subjects
- Cell Line, Hot Temperature, Humans, Indicators and Reagents, Interleukin-6 metabolism, Lipopolysaccharides pharmacology, Peptidoglycan pharmacology, Teichoic Acids pharmacology, Cell Wall chemistry, Pyrogens pharmacology, Staphylococcus aureus chemistry, Sterilization
- Abstract
As opposed to endotoxins very little is known about the heat resistance of Gram positive pyrogens. The aim of this study is to examine the pyrogenic activity of the cell wall components lipoteichoic acid and peptidoglycan from Staphylococcus aureus after moist heat sterilisation. The pyrogenic activity is determined as the ability of the substances to induce interleukin-6 secretion in Mono Mac 6 cells. The standard terminal moist heat sterilisation procedures (121 degrees C for 15min and 134 degrees C for 3min) are not able to inactivate the pyrogenic activity of S. aureus lipoteichoic acid and peptidoglycan. However after longer treatment times the pyrogenic activity of lipoteichoic acid is removed at both 121 degrees C and 134 degrees C. In contrast the activity of peptidoglycan is not removed after 160min at neither 121 degrees C nor 134 degrees C where only a 2-log reduction is obtained. In conclusion the terminal moist heat sterilisation procedures described by the European Pharmacopoeia are not able to inactivate the interleukin-6 inducing activity of S. aureus lipoteichoic acid and peptidoglycan.
- Published
- 2008
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30. Immunomodulatory effects of honey cannot be distinguished from endotoxin.
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Timm M, Bartelt S, and Hansen EW
- Subjects
- Animals, Cell Line, Granulocytes cytology, Granulocytes immunology, Humans, Interleukin-6 immunology, Monocytes cytology, Monocytes immunology, Polymyxin B metabolism, Wound Healing immunology, Endotoxins immunology, Honey, Immunologic Factors immunology
- Abstract
In recent years, the use of honey has re-emerged as a remedy for wound treatment. Effects of honey have been related to the presence of an unidentified component that induces release of inflammatory cytokines from monocytic cells. The present study was intended to further characterize the reported in vitro effects of honey. Our results show that natural honeys induce interleukin-6 release from Mono Mac 6 cells as well as release of reactive oxygen species from all-trans retinoic acid (ATRA) differentiated HL-60 cells. The natural honeys contained substantial amounts of endotoxin, and the responses observed in the cell based assays were similar to the responses induced by endotoxin alone. In addition, we determined that the immunomodulatory component present in the natural honeys was retained in the ultra filtrated fraction with a molecular weight greater than 20 kDa. The component was resistant to boiling and its immunomodulatory activity could be abrogated by the addition of polymyxin B. We speculate that the observed in vitro immunomodulatory effects of honey might solely be explained by the endotoxin content in the natural honeys.
- Published
- 2008
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31. Proton spin diffusion in polyethylene as a function of magic-angle spinning rate. A phenomenological approach.
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Jia Z, Zhang L, Chen Q, and Hansen EW
- Abstract
Starting from the phenomenological Bloembergen-Purcell-Pound equation a relation between magic-angle spinning (MAS) rate and spin diffusion is derived. The resulting model equation was fitted to observed spin diffusion versus MAS rate data obtained at 298 K on an high-density polyethylene sample, revealing a reduction in the effective spin diffusivity by (65 + 5)% when increasing the MAS rate from 2 to 12 kHz. The same model equation enabled the rigid-lattice diffusivity to be estimated and was found to be only slightly higher, by approximately 10%, compared to the spin diffusivity observed at the lowest MAS rate applied (2 kHz). Moreover, the model equation predicts a reduction in the effective spin diffusivity by more than 90% when increasing the MAS rate to more than 30 kHz.
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- 2008
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32. Airway inflammation and adjuvant effect after repeated airborne exposures to di-(2-ethylhexyl)phthalate and ovalbumin in BALB/c mice.
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Larsen ST, Hansen JS, Hansen EW, Clausen PA, and Nielsen GD
- Subjects
- Adjuvants, Immunologic administration & dosage, Aerosols, Aluminum Hydroxide, Animals, Bronchoalveolar Lavage Fluid cytology, Cells, Cultured, Cytokines metabolism, Diethylhexyl Phthalate administration & dosage, Disease Models, Animal, Dose-Response Relationship, Drug, Eosinophils drug effects, Female, Humans, Immunoglobulin E blood, Immunoglobulin G blood, Inflammation immunology, Inflammation metabolism, Inflammation pathology, Lymphocytes drug effects, Mice, Mice, Inbred BALB C, Neutrophils drug effects, Ovalbumin, Plasticizers administration & dosage, Respiratory Hypersensitivity immunology, Respiratory Hypersensitivity metabolism, Respiratory Hypersensitivity pathology, Risk Assessment, Adjuvants, Immunologic toxicity, Diethylhexyl Phthalate toxicity, Inflammation chemically induced, Inhalation Exposure, Plasticizers toxicity, Respiratory Hypersensitivity chemically induced
- Abstract
Background: Epidemiological studies have suggested an association between exposure to phthalate plasticizers, including di-(2-ethylhexyl)phthalate (DEHP), and increased prevalence of asthma, rhinitis or wheezing. Furthermore, studies in mice have demonstrated an adjuvant effect from DEHP after parenteral administration with the model allergen ovalbumin (OVA)., Objective: Exposures to DEHP were investigated for adjuvant effects and airway inflammation in a mouse inhalation model., Methods: BALB/cJ mice were exposed to aerosols of 0.022-13 mg/m(3) DEHP and 0.14 mg/m(3) OVA 5 days/week for 2 weeks and thereafter weekly for 12 weeks. Mice exposed to OVA alone or OVA+Al(OH)(3) served as control groups. Finally, all groups were exposed to a nebulized 1% OVA solution on three consecutive days. Serum, bronchoalveolar lavage (BAL) fluid, and draining lymph nodes were collected 24h later., Results: In the OVA+Al(OH)(3) group, significantly increased levels of OVA-specific IgE and IgG1 in serum as well as of eosinophils in BAL fluid were observed. DEHP affected OVA-specific IgG1 production in a concentration-dependent manner, whereas little effect was seen on IgE and IgG2a. Dose-dependent increases in inflammatory cells were observed in BAL fluids, leading to significantly higher lymphocyte, neutrophil and eosinophil numbers in the OVA+13 mg/m(3) DEHP group. Ex vivo cytokine secretion by cultures of draining lymph nodes suggested that DEHP has a mixed Th1/Th2 cytokine profile., Conclusion: Airborne DEHP is able to increase serum IgG1 and lung inflammatory cell levels, but only at very high concentrations. Realistic DEHP levels do not have an adjuvant effect or induce allergic lung inflammation in the present mouse model.
- Published
- 2007
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33. Fluid self-diffusion in Scots pine sapwood tracheid cells.
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Johannessen EH, Hansen EW, and Rosenholm JB
- Subjects
- Cell Wall physiology, Computer Simulation, Diffusion, Magnetic Resonance Spectroscopy methods, Models, Theoretical, Pinus physiology, Pinus sylvestris, Toluene analysis, Water analysis, Cell Wall chemistry, Pinus chemistry, Pinus cytology, Toluene chemistry, Water chemistry
- Abstract
The self-diffusion coefficients of water and toluene in Scots pine sapwood was measured using low field pulsed field gradient nuclear magnetic resonance (PFG-NMR). Wood chips of 8 mm diameter were saturated with the respective liquids, and liquid self-diffusion was then traced in one dimension orthogonal to the tracheid cell walls in the wood's radial direction. The experimental echo attenuation curves were exponential, and characteristic self-diffusion coefficients were produced for diffusion times spanning from very short times to times on the order of magnitude of seconds. Observed self-diffusion coefficients were decaying asymptotically as a function of diffusion time, an effect which was ascribed to the cell walls' restriction on confined liquid diffusion. The observed self-diffusion behavior in Scots pine sapwood was compared to self-diffusion coefficients obtained from simulations of diffusion in a square. Principles of molecular displacements in confined geometries were used for elucidating the wood's cellular structure from the observed diffusion coefficients. The results were compared with a mathematical model for diffusion between parallel planes.
- Published
- 2006
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34. Utilization of the human cell line HL-60 for chemiluminescence based detection of microorganisms and related substances.
- Author
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Timm M, Hansen EW, Moesby L, and Christensen JD
- Subjects
- Bacillus subtilis isolation & purification, Bacillus subtilis metabolism, Candida albicans isolation & purification, Candida albicans metabolism, Cell Differentiation, Drug Contamination, HL-60 Cells drug effects, HL-60 Cells microbiology, Humans, Indicators and Reagents, Lipopolysaccharides pharmacology, Luminescence, Luminol, Pyrogens isolation & purification, Reactive Oxygen Species analysis, Reactive Oxygen Species metabolism, Reproducibility of Results, Teichoic Acids pharmacology, Time Factors, Tretinoin, Biological Assay methods, HL-60 Cells metabolism, Pyrogens analysis
- Abstract
In this paper we describe a new pyrogen assay using the human leukemia cell line HL-60. The cell line is differentiated using all-trans retinoic acid (ATRA) to generate a cell population that resembles mature granulocytes. The differentiated HL-60 cell is capable of generating reactive oxygen species (ROS) when challenged with pyrogenic substances. In a luminol enhanced chemilumimetric assay the responsiveness of differentiated HL-60 cells is tested towards Salmonella typhimurium, Bacillus subtilis, Saccharomyces cerevisiae, Candida albicans, lipopolysaccharide (LPS) and lipoteichoic acid (LTA). The results show a poor sensitivity to S. typhimurium but displays good sensitivity towards B. subtilis, LTA and LPS. Furthermore, the sensitivity towards the yeasts C. albicans and S. cerevisiae is considerably better than obtained in other in vitro cell systems. Overall these results indicate that the HL-60 cell assay possibly could be evolved to a supplementary assay for the known pyrogenic detection assays. Furthermore, the utilization of the assay for pyrogenic examination of recombinant drugs derived from yeast expression systems would be relevant to examine.
- Published
- 2006
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35. Pore morphology of porous polymer particles probed by NMR relaxometry and NMR cryoporometry.
- Author
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Hansen EW, Fonnum G, and Weng E
- Abstract
The pore size distribution (PSD) and pore connectivity (PC) within porous polymer particles are probed by combining NMR cryoporometry and NMR relaxometry (spin-spin relaxation). With water as a probe molecule, the constant K in the so-called Gibbs-Thompson equation and the surface relaxivity (rho2) were determined to be K = (420 +/- 50) KA and rho2 = (0.44 +/- 0.01) x 10(-6) ms(-1), respectively. Also, the thickness of the interface layer was estimated to be of the order of one monolayer of water molecules. A detailed analysis of the complete set of NMR data enabled the morphology or pore structure to be probed, and is thoroughly discussed in the text.
- Published
- 2005
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36. Dry and moist heat sterilisation cannot inactivate pyrogenicity of Gram positive microorganisms.
- Author
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Moesby L, Hansen EW, Christensen JD, Høyer CH, Juhl GL, and Olsen HB
- Subjects
- Animals, Humans, Pyrogens, Rabbits, Gram-Positive Bacteria pathogenicity, Hot Temperature, Sterilization methods
- Abstract
In the monocytic cell line Mono Mac 6 pyrogens induce interleukin-6 secretion dose dependently. The aim of this study is to examine the interleukin-6 inducing capacity of Gram positive Staphylococcus aureus and Bacillus subtilis endospores after moist and dry heat sterilisation. Moist heat sterilisation of B. subtilis endospores for 15 min at 121 degrees C and 134 degrees C can only reduce the interleukin-6 inducing capacity to 57% and 63%, respectively, compared to untreated. Moist heat sterilisation of S. aureus for 60 min at 121 degrees C and 134 degrees C does not reduce the interleukin-6 inducing capacity of S. aureus. On the contrary moist heat sterilisation at 134 degrees C for 10, 20 and 40 min significantly increases the interleukin-6 inducing capacity compared to untreated S. aureus. This is confirmed in the rabbit pyrogen test. Dry heat sterilisation of B. subtilis endospores at 220 degrees C for 45 min reduces the interleukin-6 inducing capacity to 2% compared to untreated endospores. Dry heat treatment of S. aureus at 220 degrees C for 30 min only reduces the activity to 55%. However, after 250 degrees C for 30 min or 220 degrees C for 6h there is no detectable activity of S. aureus. In conclusion, neither the interleukin-6 inducing activity nor the pyrogenicity of S. aureus and endospores of B. subtilis can be inactivated by the heat sterilisation procedures described by the European Pharmacopoeia.
- Published
- 2005
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37. Regulation of interleukin-6 secretion in murine pituicytes.
- Author
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Thorn A, Tuxen M, Moesby L, Hansen EW, and Christensen JD
- Subjects
- Animals, Cells, Cultured, Dose-Response Relationship, Drug, Drug Synergism, Imines pharmacology, Interferon-gamma pharmacology, Interleukin-1 pharmacology, Male, Mice, Mice, Inbred Strains, Nitric Oxide metabolism, Nitric Oxide Donors pharmacology, Nitric Oxide Synthase antagonists & inhibitors, Nitroso Compounds pharmacology, Pituitary Gland cytology, Pituitary Gland drug effects, Interleukin-6 metabolism, Pituitary Gland metabolism
- Abstract
Pituicytes, the astrocytic glial cells of the neural lobe, are known to secrete interleukin-6 and nitric oxide upon stimulation with various inflammatory mediators, i.e. interleukin-1beta. Nitric oxide is described to modulate the secretion of interleukin-6 in various cell types. The aim of the present study was to investigate the effect of nitric oxide on interleukin-1beta induced interleukin-6 secretion. Furthermore the effect of interferon-gamma on interleukin-6 and nitric oxide release was investigated. Cultures of pituicytes were prepared of neural lobes from male mice. The effect of interleukin-1beta and interferon-gamma on interleukin-6 and nitric oxide secretion was investigated in pituicytes cultured for 14 days. The secretion of interleukin-6 and nitric oxide was determined after 24 h of stimulation. Pituicytes secrete interleukin-6 upon stimulation with interleukin-1beta dose dependently but did not induce any detectable nitric oxide release. Co-stimulation with interferon-gamma and interleukin-1beta induced a significant nitric oxide release. In addition interferon-gamma inhibits interleukin-1beta induced interleukin-6 secretion dose dependently. The observed effect of interferon-gamma on interleukin-6 secretion was not affected by the specific inducible nitric oxide synthase inhibitor 1400W (N-(3-[aminomethyl]benzyl)acetamidine). Furthermore interferon-gamma dose dependently inhibits unstimulated interleukin-6 secretion. Use of the nitric oxide releaser DETA/NO (2,2'-(hydroxynitrosohydrazono)bis-ethanimine) demonstrated that nitric oxide does not inhibit interleukin-1beta induced interleukin-6 secretion. These results demonstrated that nitric oxide has no influence on interleukin-1beta induced interleukin-6 secretion in cultured pituicytes. However the results are showing that interferon-gamma has an inhibitory effect on interleukin-6 secretion.
- Published
- 2005
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38. Pulsed-field gradient nuclear magnetic resonance study of transport properties of fluid catalytic cracking catalysts.
- Author
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Kortunov P, Vasenkov S, Kärger J, Fé Elía M, Perez M, Stöcker M, Papadopoulos GK, Theodorou D, Drescher B, McElhiney G, Bernauer B, Krystl V, Kocirik M, Zikanova A, Jirglova H, Berger C, Gläser R, Weitkamp J, and Hansen EW
- Subjects
- Catalysis, Diffusion, Particle Size, Porosity, Magnetic Resonance Spectroscopy, Zeolites chemistry
- Abstract
Pulsed-field gradient nuclear magnetic resonance (PFG NMR) has been applied to study molecular diffusion in industrial fluid catalytic cracking (FCC) catalysts and in USY zeolite for a broad range of molecular displacements and temperatures. The results of this study have been used to elucidate the relevance of molecular transport on various displacements for the rate of molecular exchange between catalyst particles and their surroundings. It turned out that this rate, which may determine the overall rate and selectivity of FCC process, is primarily related to the diffusion mode associated with displacements larger than the size of zeolite crystals located in the particles but smaller than the size of the particles. This conclusion has been confirmed by comparative studies of the catalytic performance of different FCC catalysts.
- Published
- 2005
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39. Endospores of B subtilis are pyrogenic and activate Mono Mac 6 cells: importance of the CD14 receptor.
- Author
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Moesby L, Hansen EW, Christensen JD, Tommerup L, and Nielsen C
- Subjects
- Cell Division drug effects, Cell Line, Humans, Interleukin-6 metabolism, Kinetics, Lipopolysaccharides toxicity, Monocytes drug effects, Monocytes microbiology, Recombinant Proteins pharmacology, Spores, Bacterial physiology, Bacillus subtilis pathogenicity, Bacillus subtilis physiology, Lipopolysaccharide Receptors physiology
- Abstract
The monocytic cell line Mono Mac 6 is sensitive to pyrogens and interleukin-6 secretion is induced after exposure to pyrogens. The aim of this study is to examine the pyrogenic activity and the interleukin-6-inducing capacity of the Gram-positive B. subtilis bacteria, endospores and isolated cell wall components. Furthermore the involvement of CD14 in activation of interleukin-6 release is investigated. All test substances are pyrogenic in the rabbit pyrogen test. The test substance is incubated with monocytic cells (Mono Mac 6) for 24 h and the secreted interleukin-6 is determined in a sandwich immunoassay. B. subtilis bacteria and endospores induce interleukin-6 in a dose-dependent manner. Endospores are less potent than bacteria. Lipoteichoic acid (LTA) isolated from B. subtilis induces interleukin-6 in a dose-dependent manner, whereas muramyl dipeptide (MDP) is unable to induce interleukin-6. Lipopolysaccharides (LPS) dose-dependently induce interleukin-6 release, but the curve differs from that of LTA both in shape and offset. The interleukin-6 secretion induced by LPS, LTA and B. subtilis bacteria can be blocked by 73-85% by an antibody directed against CD14, whereas the antibody only blocks 25% of B. subtilis endospores-induced interleukin-6 release. The results might indicate that B. subtilis endospores use an additional pathway to CD14 to activate mononuclear cells.
- Published
- 2003
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40. Inducible nitric oxide synthase is responsible for nitric oxide release from murine pituicytes.
- Author
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Kjeldsen TH, Rivier C, Lee S, Hansen EW, Christensen JD, and Moesby L
- Subjects
- Animals, Gene Expression Regulation, Enzymologic drug effects, Glial Fibrillary Acidic Protein analysis, Inflammation Mediators metabolism, Interleukin-6 metabolism, Lipopolysaccharides pharmacology, Male, Mice, Mice, Inbred ICR, Nitric Oxide Synthase genetics, Nitric Oxide Synthase Type I, Nitric Oxide Synthase Type II, Nitric Oxide Synthase Type III, Nitrites metabolism, Pituitary Gland, Posterior cytology, Pituitary Gland, Posterior immunology, RNA, Messenger analysis, Nitric Oxide metabolism, Nitric Oxide Synthase metabolism, Pituitary Gland, Posterior enzymology
- Abstract
This study investigated whether pituicytes were able to produce and release nitric oxide (NO), and which type of nitric oxide synthase (NOS) would be responsible for this phenomenon. Lipopolysaccharide (LPS) 1 micro g/ml was used as inflammatory mediator. Because pituicytes are known to secrete interleukin (IL)-6 upon stimulation with LPS, this parameter was also investigated. Cultured pituicytes, from 4-week-old male mice, were stimulated with LPS for 6 h or 24 h. At 24 h, there was a significant increase in accumulated nitrite indicating NO formation. In contrast, IL-6 release was already significantly higher 6 h after stimulation and further increased at 24 h. The correlation between accumulated nitrite and secreted IL-6 was 0.84 after 24 h of incubation with LPS. The expression of inducible NOS (iNOS) mRNA in the pituicytes was significantly higher than the control level after 6 h and 24 h of exposure to LPS, with levels at 6 h being significantly higher than those at 24 h. There was no detected expression of endothelial NOS or neuronal NOS mRNA. Cultured pituicytes were also subjected to immunocytochemistry for iNOS protein at 6, 12, and 24 h after stimulation with LPS. Most cells were positive for iNOS, but there were no observable differences with the time points that we used. Collectively, these results show that pituicytes are able to produce NO, and that the inducible form of NOS is responsible for this production. Furthermore, there is a weak correlation between NO and IL-6 released from pituicytes after 24 h of stimulation with LPS.
- Published
- 2003
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41. Utility of the dentin matrix protein 1 (DMP1) gene for resolving mammalian intraordinal phylogenetic relationships.
- Author
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Van Den Bussche RA, Reeder SA, Hansen EW, and Hoofer SR
- Subjects
- Amino Acid Sequence, Animals, Molecular Sequence Data, Sequence Alignment, Chiroptera genetics, Evolution, Molecular, Phosphoproteins genetics, Phylogeny
- Abstract
We sequenced exon 6 of the nuclear dentin matrix protein 1 (DMP1) gene from 19 species of bats (order Chiroptera) to assess the utility of this gene for higher-level phylogenetic studies. Bayesian analysis revealed high support (posterior probabilities >/=0.95) for monophyly of Noctilionoidea (Phyllostomidae, Noctilionidae, and Mormoopidae), all genera and most families examined. Comparison of the phylogenetic information present in DMP1 with mitochondrial rDNA and nuclear RAG2 genes indicated no significant heterogeneity. Thus, we concatenated these three data sets into a single "total evidence" phylogenetic analysis. Combined analysis was congruent with study of RAG2 and combined RAG2 and mtrDNA sequences, but improved support (Bayesian posterior probabilities) for many nodes. Our results indicate that exon 6 of DMP1 is rapidly evolving, able to tolerate non-frame shifting insertion and deletion events, is more variable than RAG2, and provides phylogenetic resolution from the interfamilial to infraclass levels in mammals.
- Published
- 2003
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- View/download PDF
42. Baclofen influences lipopolysaccharide-mediated interleukin-6 release from murine pituicytes.
- Author
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Kjeldsen TH, Hansen EW, Christensen JD, and Moesby L
- Subjects
- Animals, Cells, Cultured, Male, Mice, Pituitary Gland, Posterior cytology, Baclofen pharmacology, Interleukin-6 metabolism, Lipopolysaccharides pharmacology, Pituitary Gland, Posterior drug effects, Pituitary Gland, Posterior metabolism
- Abstract
Pituicytes, the glial cells of the neurohypophysis, secrete interleukin-6 upon stimulation with various inflammatory mediators, i.e. lipopolysaccharide. Previous studies have identified several receptors on pituicytes. This study investigates the effect of GABA(B) receptor activation on interleukin-6 release from pituicytes. Cultured murine pituicytes were stimulated for 24 h with lipopolysaccharide (0.5 ng/ml) to give a significant interleukin-6 release compared to control. The interleukin-6 release was significantly potentiated by the GABA(B) receptor agonist (R)-4-amino-3-(4-chlorophenyl) butanoic acid (R-baclofen; 10, 100 or 500 microM). However, R-baclofen itself (10, 100 or 500 microM) did not stimulate the interleukin-6 secretion. Furthermore, the potent GABA(B) receptor antagonists 3-[[(3,4-Dichlorophenyl)methyl]amino]propyl]diethoxymethyl) phosphinic acid (CGP52432; 30 or 300 microM) and (RS)-3-Amino-2-(4-chlorophenyl)-2-hydroxypropyl-sulphonic acid (2-OH-saclofen; 10 or 100 microM) did not remove the effect of R-baclofen (100 microM). Gamma-amino butyric acid (GABA; 30 or 300 microM) did not alter the lipopolysaccharide-mediated interleukin-6 response. After 30 min, intracellular cyclic AMP (cAMP) was higher in cells stimulated with lipopolysaccharide compared to control, and R-baclofen significantly inhibited this increase in cAMP. Nevertheless, neither lipopolysaccharide nor R-baclofen had any effect on intracellular cAMP after 24 h of stimulation. The results suggest that the effect of R-baclofen on lipopolysaccharide-stimulated interleukin-6 secretion is independent of GABA(B) receptors.
- Published
- 2002
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43. Characterization and phylogenetic utility of the mammalian protamine p1 gene.
- Author
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Van Den Bussche RA, Hoofer SR, and Hansen EW
- Subjects
- Amino Acid Sequence, Animals, Artiodactyla classification, Artiodactyla genetics, Base Composition, Carnivora classification, Carnivora genetics, Chiroptera classification, Chiroptera genetics, DNA chemistry, DNA genetics, Humans, Mammals classification, Molecular Sequence Data, Primates classification, Primates genetics, Rodentia classification, Rodentia genetics, Sequence Alignment, Sequence Analysis, DNA, Sequence Homology, Amino Acid, Mammals genetics, Phylogeny, Protamines genetics
- Abstract
We sequenced the protamine P1 gene (ca. 450 bp) from 20 bats (order Chiroptera) and the flying lemur (order Dermoptera). We compared these sequences with published sequences from 19 other mammals representing seven orders (Artiodactyla, Carnivora, Cetacea, Perissodactyla, Primates, Proboscidea, and Rodentia) to assess structure, base compositional bias, and phylogenetic utility. Approximately 80% of second codon positions were guanine, resulting in protamine proteins containing a high frequency of arginine residues. Our data indicate that codon usage for arginine differs among higher mammalian taxa. Parsimony analysis of 40 species representing nine orders produced a well-resolved tree in which most nodes were supported strongly, except at the lowest taxonomic levels (e.g., within Artiodactyla and Vespertilionidae). These data support monophyly of several taxa proposed by morphologic and molecular studies (all nine orders: Laurasiatheria, Cetartiodactytla, Yangochiroptera, Noctilionoidea, Rhinolophoidea, Vespertilionoidea, Phyllostomidae, Natalidae, and Vespertilionidae) and, in agreement with recent molecular studies, reject monophyly of Archonta, Volitantia, and Microchiroptera. Bats were sister to a clade containing Perissodactyla, Carnivora, and Cetartiodactyla, and, although not unequivocally, rhinolophoid bats (traditional microchiropterans) were sister to megachiropterans. Sequences of the protamine P1 gene are useful for resolving relationships at and above the familial level in bats, and generally within and among mammalian orders, but with some drawbacks. The coding and intervening sequences are small, producing few phylogenetically informative characters, and aligning the intron is difficult, even among closely related families. Given these caveats, the protamine P1 gene may be important to future systematic studies because its functional and evolutionary constraints differ from other genes currently used in systematic studies., ((C)2002 Elsevier Science (USA).)
- Published
- 2002
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44. Endotoxin testing of proteins for parenteral administration using the Mono Mac 6 assay.
- Author
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Moesby L, Hansen EW, and Christensen JD
- Subjects
- Administration, Oral, Animals, Biological Assay methods, Cell Line, Humans, Monocytes cytology, Proteins, Rabbits, Sensitivity and Specificity, Drug Contamination, Endotoxins analysis, Monocytes physiology, Pharmaceutical Preparations standards
- Abstract
Background: Pharmaceutical products containing proteins cause problems in testing for endotoxin and pyrogens. Many proteins interfere with the LAL test and the proteins are immunogenic in rabbits. The monocytic cell line Mono Mac 6 is an alternative assay for detection of endotoxin and other pyrogens., Objective: To evaluate the use of the Mono Mac 6 assay for quantitative detection of endotoxin in proteins., Method: The quantitative detection of endotoxin in the three pharmaceutical products human albumin, gamma-globulin and somatropin was evaluated., Results: For the three proteins the detection limit of the Mono Mac 6 assay was far below the threshold endotoxin limit described by the European Pharmacopoeia. Interference of two of the proteins with the Mono Mac 6 assay was observed, but the problems could be overcome either by dilution of the product or by comparison of the test with an endotoxin standard curve prepared in a solution of the respective pyrogen-free protein., Conclusion: The Mono Mac 6 assay is a reliable method for quantitative detection of endotoxin in proteins.
- Published
- 2000
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45. Ultrasonication of pyrogenic microorganisms improves the detection of pyrogens in the Mono Mac 6 assay.
- Author
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Moesby L, Hansen EW, and Christensen JD
- Subjects
- Cell Line, Humans, Monocytes cytology, Monocytes drug effects, Pyrogens chemistry, Pyrogens pharmacology, Candida albicans chemistry, Gram-Negative Bacteria chemistry, Gram-Positive Bacteria chemistry, Interleukin-6 metabolism, Monocytes microbiology, Sonication
- Abstract
The monocytic cell line Mono Mac 6 is sensitive to pyrogens. When exposed to pyrogens secretion of interleukin-6 is induced. However, some eukaryotic pyrogenic microorganisms are not detectable. The aim of this study is to introduce a pretreatment of samples to expand the detection range of the assay. The interleukin-6 inducing capacity of a broad spectrum of UV-killed and ultrasonicated microorganisms is examined in Mono Mac 6 cells. The interleukin-6 secretion is determined in a sandwich immunoassay (DELFIA). The Mono Mac 6 assay is able to detect UV-killed Bacillus subtilis, Staphylococcus aureus and Salmonella typhimurium, but neither Candida albicans nor Aspergillus niger. After ultrasonication of the microorganisms it is possible to detect C. albicans and A. niger. The interleukin-6 inducing ability of the examined microorganisms is in no case reduced after ultrasonic treatment. However, ultrasonication of S. aureus results in a 100-fold increase in the interleukin-6 response. Even after ultrasonication Streptococcus faecalis can not be detected. Ultrasonication is an easy and simple method for expanding the detection range in the Mono Mac 6 assay.
- Published
- 2000
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46. A comparative study of Mono Mac 6 cells, isolated mononuclear cells and Limulus amoebocyte lysate assay in pyrogen testing.
- Author
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Moesby L, Jensen S, Hansen EW, and Christensen JD
- Subjects
- Biological Assay, Cell Line, Humans, Immunoassay, In Vitro Techniques, Indicators and Reagents, Interleukin-6 metabolism, Kinetics, Lipopolysaccharides pharmacology, Monocytes metabolism, Stimulation, Chemical, Tumor Necrosis Factor-alpha metabolism, Limulus Test, Monocytes drug effects, Pyrogens pharmacology
- Abstract
Pyrogen induced secretion of interleukin 6 (IL-6) in Mono Mac 6 (MM6) cells was measured. The ability of the MM6 cell culture to detect pyrogens was compared to the Limulus amoebocyte lysate (LAL) test and isolated mononuclear cells (MNC). The detection limit of MM6 for lipopolysaccharide (LPS) and Staphylococcus aureus was comparable to that of MNC. Aspergillus niger and Candida albicans induced IL-6 in isolated MNC, but not in MM6. The detection limit for Salmonella typhimurium in the MM6 assay was comparable to that of the LAL assay. As expected, S. aureus and C. albicans did not show any LAL activity. A. niger and Influenza virus showed some activity in the LAL test, but could not be detected by MM6 cells. In conclusion, the MM6 assay is a good supplement to the current pyrogen assays for detection of LPS, S. aureus and S. typhimurium, but the MM6 assay could not detect A. niger, C. albicans and Influenza virus.
- Published
- 1999
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47. Endotoxin-stimulated release of cytokines by cultured cells from the murine neurohypophysis: role of dexamethasone and indomethacin.
- Author
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Hansen EW, Malling D, and Christensen JD
- Subjects
- Animals, Cells, Cultured, Cellular Senescence, Interleukin-1 metabolism, Interleukin-6 metabolism, Male, Mice, Pituitary Gland, Posterior drug effects, Cytokines metabolism, Dexamethasone pharmacology, Indomethacin pharmacology, Lipopolysaccharides pharmacology, Pituitary Gland, Posterior metabolism
- Abstract
It is well established that many cell types produce inflammatory cytokines and we were interested to see whether cells in the neurohypophysis had this ability. This study examines the effect of lipopolysaccharide (LPS) on cytokine production in cultured murine neural lobe (NL) cells. Cells were cultured from the neurohypophysis of mice not older than 5 days and the experiments were performed after 12 days in culture. The majority of cells in culture were immunoreactive for glial fibrillary acidic protein, indicating that the cells were pituicytes. Cytokines were measured in 24-hour samples using commercial ELISA kits. Cells growing in a medium free of endotoxin released 94.3 +/- 6.6 pg IL-6/NL/24 h (mean +/- SEM, n = 21). The release of interleukin-6 (IL-6) was reversible and increased concentration dependently with LPS in the concentration range of 0.1-1 ng/ml. The addition of 1 ng/ml LPS increased the IL-6 release 12-fold to a maximum value of 1,134 +/- 85.5 pg IL-6/NL/24 h (mean +/- SEM, n = 6). No trace of interleukin-1beta (IL-1beta) (<3 pg/NL/24 h) or tumor necrosis factor-alpha (<10 pg/NL/24 h) was detected after LPS stimulation. We examined the effect of dexamethasone (10(-6) M) and indomethacin (10(-4) M) on the release of IL-6 in submaximally stimulated cells. Dexamethasone inhibited the unstimulated and the LPS-stimulated release of IL-6 by 70 and 81%, respectively. Indomethacin had no influence on the release, and it is concluded that cyclooxygenase is not involved in the response. A close association exists between the membrane of the neurosecretory endings and the pituicytes in the neurohypophysis. This naturally raises the question as to whether IL-6 might reflect a physiological connection between the two cell types.
- Published
- 1999
- Full Text
- View/download PDF
48. Adrenaline influences the release of interleukin-6 from murine pituicytes: role of beta2-adrenoceptors.
- Author
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Christensen JD, Hansen EW, Frederiksen C, Mølris M, and Moesby L
- Subjects
- Adrenergic beta-Antagonists pharmacology, Animals, Atenolol pharmacology, Cells, Cultured, Drug Interactions, Interleukin-1 metabolism, Mice, Pituitary Gland, Posterior cytology, Pituitary Gland, Posterior metabolism, Propanolamines pharmacology, Propranolol pharmacology, Epinephrine pharmacology, Interleukin-6 metabolism, Pituitary Gland, Posterior drug effects, Receptors, Adrenergic, beta-2 metabolism
- Abstract
In this study, we examined the effect of adrenaline and interleukin-1beta on interleukin-6 secretion from cultured murine neurohypophyseal cells. Cells were cultured from neurohypophyses of 3- to 5-week-old mice and experiments were performed after 13 days in culture. Interleukin-6 was measured in 24-h samples using a sandwich fluoroimmunoassay. Unstimulated cells released 19+/-3 fmol interleukin-6/neurohypophysis/24 h (mean +/- S.E.M., n = 42). Adrenaline and interleukin-1beta increased the release of interleukin-6 from the cells in a concentration-dependent manner. Incubation with adrenaline (10(-6) M) or interleukin-1beta (11 pM) induced maximal secretion of interleukin-6, resulting in a 2.2-fold and 19.8-fold increase, respectively (P<0.01). The action of adrenaline (10(-6) M) and interleukin-1beta (1.1 pM) was examined separately and together. The sum of the effect of the two compounds given alone was significantly less (P<0.05) than the effect when adrenaline and interleukin-1beta were given together. We examined the effect of the beta-adrenoceptor antagonist propranolol (3.4x10(-6) M), the beta2-adrenoceptor antagonist (+/-)-1-[2,3-(Dihydro-7-methyl-1H-inden-4-yl)oxy]-3-[(1-methyl-eth yl)amino]-2-butanol (ICI 118551) (10(-7) M) and the beta1-adrenoceptor antagonist atenolol (10(-7) M and 10(-6) M) on the adrenaline-stimulated release of interleukin-6. Propranolol and ICI 118551 completely blocked the action of adrenaline, whereas atenolol was inactive. It is concluded that the stimulatory effect of adrenaline is mediated via beta2-adrenoceptors.
- Published
- 1999
- Full Text
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49. Pyrogen testing of lipid-based TPN using Mono Mac 6 monocyte cell line and DELFIA.
- Author
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Moesby L, Hansen EW, and Christensen JD
- Subjects
- Biological Assay, Cell Line, Cross Reactions, Europium, Fluoroimmunoassay methods, Humans, Indicators and Reagents, Interleukin-6 analysis, Quality Control, Drug Contamination, Lipopolysaccharides analysis, Monocytes chemistry, Parenteral Nutrition, Total, Pyrogens analysis
- Abstract
Objective: Measurement of lipopolysaccharide (LPS) induced interleukin-6 (IL-6) secretion in Mono Mac 6 cells., Method: Dissociation-enhanced lanthanide fluoro immunoassay (DELFIA), a technique based on time-resolved fluorescence., Results: A comparison of DELFIA and the B9 bioassay showed a correlation between the results of the two assays. DELFIA did not show any crossreactivity with the human cytokines TNFalpha, IL-1beta, IL-1alpha, IL-2, IL-4, IFNgamma, murine IL-6 or LPS. In aqueous solution the detection limit was 2.5 pg LPS/ml, and in a 25% dilution of a lipid-based total parenteral nutrition (TPN) product it was 25 pg LPS/ml. TPN did not interfere with the DELFIA assay, but the IL-6 secretion from the Mono Mac 6 cells was inhibited at TPN concentrations above 25%., Conclusion: A combination of Mono Mac 6 cells with DELFIA was found to be a reliable method for detecting LPS, but further validation by independent laboratories is justified.
- Published
- 1997
- Full Text
- View/download PDF
50. Carbon NMR used in probing the exchange of ethanol with water in water-saturated cement pastes.
- Author
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Hansen EW and Gran HC
- Subjects
- Diffusion, Ethanol, Water, Construction Materials, Magnetic Resonance Spectroscopy
- Abstract
The exchange of water by ethanol in two water-saturated cement pastes has been investigated by carbon NMR. The two cement pastes differed only in their thermal history. The diffusion of ethanol into the cement paste was shown to be described by Fickian diffusion, assuming one-dimensional diffusion under perfect sink boundary conditions. The diffusion coefficients were calculated to be (1.28 +/- 0.14) 10(-7) cm2/s for the virgin cement sample and (4.38 +/- 0.57) 10(-7) m2/s for the preheated cement sample (preheated at 105 degrees C for 12 h), respectively. The measurements indicate an extensive exchange between water and ethanol.
- Published
- 1996
- Full Text
- View/download PDF
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