397 results on '"Jens Jacob"'
Search Results
352. 33-OR: Intact Muscle Insulin Signaling in Patients with a Gain-of-Function LRP5 Mutation Despite Decreased Insulin Sensitivity.
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SABARATNAM, RUGIVAN, LAUTERLEIN, JENS-JACOB LINDEGAARD, NIELSEN, MORTEN FROST, and HOJLUND, KURT
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Type 2 diabetes (T2D) is characterized by insulin resistance in skeletal muscle. GWAS studies have shown a link between T2D and Wnt signalling, and there is evidence that mutations in LRP5, a co-receptor in the canonical Wnt signaling pathway, may alter insulin sensitivity. Here, we investigated whether a gain-of-function (GoF) LRP5 mutation causing high bone mass is accompanied by changes in insulin sensitivity and abnormalities in the insulin signalling pathway in skeletal muscle. Skeletal muscle biopsies were obtained before and after a euglycemic-hyperinsulinemic clamp (3-h, 40 mU/min/m2) from 13 patients with GoF LRP5 mutation (T253I) and 14 age, and weight-matched controls. Protein abundance/phosphorylation of key mediators of insulin signalling to glucose transport and glycogen synthesis, such as Akt, TBC1D4, glycogen synthase kinase 3 (GSK3α and ß) and Erk1/2 were investigated. Insulin sensitivity measured as insulin-stimulated glucose disposal (Rd) was reduced (25%) in GoF LRP5 mutation carriers (p<0.05). However, the insulin-stimulated phosphorylation of Akt at Ser473 and Thr308, TBC1D4 at Thr642 and Erk1/2 was fully intact in skeletal muscle of GoF LRP5 mutation carriers. Moreover, both the basal and the insulin-mediated inhibitory phosphorylation of GSK3 (α and ß) were unaltered in muscle of LRP5 mutation carriers compared with controls. To further investigate the molecular consequences of this GoF LRP5 mutation, we are currently investigating key regulators of Wnt signalling (activity of ß-catenin and CaMKII) and performing RNA-sequencing in muscle. In conclusion, our data demonstrate that reduced insulin sensitivity in GoF LRP5 mutation carriers is not explained by abnormalities in the classical components of the insulin signalling cascade in skeletal muscle. This suggests that the GOF LRP5 mutation negatively affects insulin sensitivity by other mechanisms possible involving over-activation in Wnt signalling. Disclosure: R. Sabaratnam: None. J. Lauterlein: None. M.F. Nielsen: None. K. Hojlund: None. [ABSTRACT FROM AUTHOR]
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- 2019
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353. Molecular Survey on Brucellosis in Rodents and Shrews - Natural Reservoirs of Novel Brucella Species in Germany?
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Karsten Nöckler, Christian Imholt, Nastasja Kratzmann, Jens A. Hammerl, S. Al Dahouk, Holger C. Scholz, Rainer G. Ulrich, and Jens Jacob
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0301 basic medicine ,Veterinary medicine ,Disease reservoir ,Rodent ,Vulpes ,030106 microbiology ,Population ,Rodentia ,Brucella ,Brucellosis ,03 medical and health sciences ,biology.animal ,Germany ,medicine ,Animals ,education ,Disease Reservoirs ,education.field_of_study ,General Veterinary ,General Immunology and Microbiology ,biology ,Shrews ,Shrew ,General Medicine ,biology.organism_classification ,medicine.disease ,Apodemus - Abstract
Brucellosis is a widespread zoonotic disease introduced from animal reservoirs to humans. In Germany, bovine and ovine/caprine brucellosis were eradicated more than a decade ago and mandatory measures in livestock have been implemented to keep the officially brucellosis-free status. In contrast, surveillance of wildlife is still challenging, and reliable data on the prevalence of brucellae in small mammal populations do not exist. To assess the epidemiology of Brucella spp. in rodents and shrews, a molecular survey was carried out. A total of 537 rodents and shrews were trapped in four federal states located throughout Germany and investigated for the presence of Brucella. Using a two-step molecular assay based on the detection of the Brucella-specific bcsp31 and IS711 sequences in tissue samples, 14.2% (n = 76) of the tested animals were positive. These originated mainly from western and south-western Germany, where preliminary analyses indicate population density-dependent Brucella prevalence in voles (Myodes glareolus) and mice (Apodemus spp.). recA typing revealed a close relationship to a potentially novel Brucella species recently isolated from red foxes (Vulpes vulpes) in Austria. The molecular detection of brucellae in various rodent taxa and for the first time in shrew species shows that these animals may be naturally infected or at least have a history of exposure to Brucella spp.
354. Diabetes og hørenedsættelse på grund af mitokondriel punktmutation
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Jens-Jacob Lindegaard Lauterlein, Inger Olsen, and Knud Yderstraede
355. Human obesity is associated with enhanced insulin signaling and accelerated differentiation of bone marrow stromal stem cell leading to premature skeletal aging
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Michaela Tencerova, Florence Figeac, Anders Kristian Haakonsson, Jens-Jacob Lindegaard Lauterlein, Tina Kamilla Nielsen, Dalia Ali, Kurt Højlund, and Moustapha Kassem
356. Ecologically-based rodent management: its effectiveness in cropping systems in South-East Asia
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Grant R. Singleton, Jens Jacob, and Peter R. Brown
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Rodent ,biology ,Agroforestry ,Ecology (disciplines) ,field populations ,rice ,food and beverages ,Rattus argentiventer ,Plant Science ,economics ,Population ecology ,Development ,Vietnam ,Environmental protection ,Indonesia ,biology.animal ,Scale (social sciences) ,population ecology ,Animal Science and Zoology ,South east asia ,Cropping ,Agronomy and Crop Science ,Food Science - Abstract
Ecologically-based rodent management (EBRM] has re-emerged as a paradigm for large scale rodent management campaigns. This concept has been tested in replicated, village-scale experiments over 4 years on rodent pests in lowland irrigated rice crops. In Indonesia, villages that practised EBRM had a mean increase in rice yield of 6%, whereas production levels were maintained in Vietnam but control costs were reduced. In both countries there was a substantial reduction in rodenticide use in villages practising EBRM. These studies provide strong evidence of the effectiveness of EBRM. The findings also highlighted the need to include end-users early in the development of management strategies. Lessons learned from these studies were extrapolated to the development of strategies for rodent management in intensive organic piggeries and poultry holdings in Europe. The challenge for these producers is not only the identification and then integration of different management actions based on our understanding of the ecology of specific rodent species, but also the integration of ecology, sociology and economics.
357. What affects bait uptake by house mice in Australian grain fields?
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D.A. Jones, Hannu Ylönen, Myfanwy J. Runcie, Grant R. Singleton, and Jens Jacob
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Agroecosystem ,Integrated pest management ,Ecology ,food and beverages ,macromolecular substances ,Pesticide ,Biology ,biology.organism_classification ,Crop ,Animal science ,Agronomy ,parasitic diseases ,Pellet ,General Earth and Planetary Sciences ,Rodenticide ,House mice ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation ,General Environmental Science ,Muridae - Abstract
The main method of pest-rodent control is the distribution of rodenticide baits. Emerging management techniques such as fertility control also may rely on the distribution of bait, but we do not know what affects bait uptake by rodents in crop fields. From October 2000 to February 2001, we measured the importance of individual characteristics (sex, weight, length, reproductive status), mouse abundance, and environmental conditions (vegetation height and cover and food quantity and quality) for free-fed pellet bait uptake by house mice (Mus domesticus). Our study was conducted in a grain-growing region of southeastern Australia using pellet bait that contained Rhodamine B (RB) as a bait marker. High bait uptake was noted when fenceline vegetation was high and pellets were spread at high densities. Lower uptake was noted when the grain crop had high protein content. Vegetation cover, mouse abundance, the amount of spilled grain after harvest, and crop height had no impact on bait uptake. The proportion of RB-positive mice decreased during removal trappings, indicating effective removal of residents. Lactating females were more likely to be RB positive than nonlactating females, possibly because of higher food intake during lactation. Because many females (79.9%) ate bait pellets, bait formulations may be used to effectively deliver fertility-control agents targeted at female house mice.
358. A possible sink for methane on Mars
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Per Nørnberg, Svend Knak Jensen, Jørgen Skibsted, Hans Jørgen Jakobsen, Ten Kate, Inge L., Haraldur Pall Gunnlaugsson, Merrison, Jonathan P., Kai Finster, Ebbe Norskov Bak, Jens Jacob Iversen, and Jens Christian Kondrup
359. Des âges de pierre et de bronze dans l'ancien et le nouveau monde : comparaisons archéologico-ethnographiques / par J. J. A. Worsaae ; traduit du danois par E. Beauvois...
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Beauvois, Eugène (1835-1912). Traducteur, Worsaae, Jens Jacob Asmussen (1821-1885). Auteur du texte, Beauvois, Eugène (1835-1912). Traducteur, and Worsaae, Jens Jacob Asmussen (1821-1885). Auteur du texte
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Avec mode texte
360. La Colonisation de la Russie et du Nord scandinave et leur plus ancien état de civilisation ['Ruslands og det skandinaviske Nordens Bebyggelse og oeldste Kulturforhold'], essai d'archéologie préhistorique comparative, par J. J. A. Worsaae. Traduit par E. Beauvois...
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Beauvois, Eugène (1835-1912). Traducteur, Worsaae, Jens Jacob Asmussen (1821-1885). Auteur du texte, Beauvois, Eugène (1835-1912). Traducteur, and Worsaae, Jens Jacob Asmussen (1821-1885). Auteur du texte
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Avec mode texte
361. The Dynamics of CO2 ‐Driven Granular Flows in Gullies on Mars
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Roelofs, Lonneke, Conway, Susan J., van Dam, Bas, van Eijk, Arjan, Merrison, Jonathan P., Iversen, Jens Jacob, Sylvest, Matthew, Patel, Manish R., Markies, Henk, van Maarseveen, Marcel, McElwaine, Jim, Kleinhans, Maarten G., de Haas, Tjalling, Roelofs, Lonneke, Conway, Susan J., van Dam, Bas, van Eijk, Arjan, Merrison, Jonathan P., Iversen, Jens Jacob, Sylvest, Matthew, Patel, Manish R., Markies, Henk, van Maarseveen, Marcel, McElwaine, Jim, Kleinhans, Maarten G., and de Haas, Tjalling
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Martian gullies are landforms consisting of an erosional alcove, a channel, and a depositional apron. A significant proportion of Martian gullies at the mid‐latitudes is active today. The seasonal sublimation of CO2 ice has been suggested as a driver behind present‐day gully activity. However, due to a lack of in situ observations, the actual processes causing the observed changes remain unresolved. Here, we present results from flume experiments in environmental chambers in which we created CO2‐driven granular flows under Martian atmospheric conditions. Our experiments show that under Martian atmospheric pressure, large amounts of granular material can be fluidized by the sublimation of small quantities of CO2 ice in the granular mixture (only 0.5% of the volume fraction of the flow) under slope angles as low as 10°. Dimensionless scaling of the CO2‐driven granular flows shows that they are dynamically similar to terrestrial two‐phase granular flows, that is, debris flows and pyroclastic flows. The similarity in flow dynamics explains the similarity in deposit morphology with levees and lobes, supporting the hypothesis that CO2‐driven granular flows on Mars are not merely modifying older landforms, but they are actively forming them. This has far‐reaching implications for the processes thought to have formed these gullies over time. For other planetary bodies in our solar system, our experimental results suggest that the existence of gully like landforms is not necessarily evidence for flowing liquids but that they could also be formed or modified by sublimation‐driven flow processes.
362. La Colonisation de la Russie et du Nord scandinave et leur plus ancien état de civilisation ['Ruslands og det skandinaviske Nordens Bebyggelse og oeldste Kulturforhold'], essai d'archéologie préhistorique comparative, par J. J. A. Worsaae. Traduit par E. Beauvois...
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Beauvois, Eugène (1835-1912). Traducteur, Worsaae, Jens Jacob Asmussen (1821-1885). Auteur du texte, Beauvois, Eugène (1835-1912). Traducteur, and Worsaae, Jens Jacob Asmussen (1821-1885). Auteur du texte
- Abstract
Avec mode texte
363. Des âges de pierre et de bronze dans l'ancien et le nouveau monde : comparaisons archéologico-ethnographiques / par J. J. A. Worsaae ; traduit du danois par E. Beauvois...
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Beauvois, Eugène (1835-1912). Traducteur, Worsaae, Jens Jacob Asmussen (1821-1885). Auteur du texte, Beauvois, Eugène (1835-1912). Traducteur, and Worsaae, Jens Jacob Asmussen (1821-1885). Auteur du texte
- Abstract
Avec mode texte
364. Dynamic behaviour of transmission towers: field measurements
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Jensen, Jens Jacob, primary and Folkestad, Gunnar, additional
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- 1984
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365. Discussion of “Cable-Suspended Roof Construction State-of-the-Art”
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Jensen., Jens Jacob, primary
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- 1972
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366. Discussion of 'Cable-Suspended Roof Construction State-of-the-Art'
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Jens Jacob Jensen.
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General Engineering ,State (computer science) ,Roof ,Civil engineering ,Geology - Published
- 1972
367. Obesity-Associated Hypermetabolism and Accelerated Senescence of Bone Marrow Stromal Stem Cells Suggest a Potential Mechanism for Bone Fragility
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Tencerova, Michaela, Frost, Morten, Figeac, Florence, Nielsen, Tina Kamilla, Ali, Dalia, Lauterlein, Jens-Jacob Lindegaard, Andersen, Thomas Levin, Haakonsson, Anders Kristian, Rauch, Alexander, Madsen, Jonna Skov, Ejersted, Charlotte, Højlund, Kurt, and Kassem, Moustapha
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Obesity is associated with increased risk for fragility fractures. However, the cellular mechanisms are unknown. Using a translational approach combining RNA sequencing and cellular analyses, we investigated bone marrow stromal stem cells (BM-MSCs) of 54 men divided into lean, overweight, and obese groups on the basis of BMI. Compared with BM-MSCs obtained from lean, obese BM-MSCs exhibited a shift of molecular phenotype toward committed adipocytic progenitors and increased expression of metabolic genes involved in glycolytic and oxidoreductase activity. Interestingly, compared with paired samples of peripheral adipose tissue-derived stromal cells (AT-MSCs), insulin signaling of obese BM-MSCs was enhanced and accompanied by increased abundance of insulin receptor positive (IR+) and leptin receptor positive (LEPR+) cells in BM-MSC cultures. Their hyper-activated metabolic state was accompanied by an accelerated senescence phenotype. Our data provide a plausible explanation for the bone fragility in obesity caused by enhanced insulin signaling leading to accelerated metabolic senescence of BM-MSCs.
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- 2019
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368. Positron emission tomography visualized stimulation of the vestibular organ is localized in Heschl's gyrus.
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Devantier, Louise, Hansen, Allan K., Mølby‐Henriksen, Jens‐Jacob, Christensen, Christian B., Pedersen, Michael, Hansen, Kim V., Magnusson, Måns, Ovesen, Therese, and Borghammer, Per
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POSITRON emission tomography , *VESTIBULAR stimulation , *VESTIBULAR apparatus , *FUNCTIONAL magnetic resonance imaging , *AUDITORY cortex , *SENSORY receptors , *SEMICIRCULAR canals - Abstract
The existence of a human primary vestibular cortex is still debated. Current knowledge mainly derives from functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) acquisitions during artificial vestibular stimulation. This may be problematic as artificial vestibular stimulation entails coactivation of other sensory receptors. The use of fMRI is challenging as the strong magnetic field and loud noise during MRI may both stimulate the vestibular organ. This study aimed to characterize the cortical activity during natural stimulation of the human vestibular organ. Two fluorodeoxyglucose (FDG)‐PET scans were obtained after natural vestibular stimulation in a self‐propelled chair. Two types of stimuli were applied: (a) rotation (horizontal semicircular canal) and (b) linear sideways movement (utriculus). A comparable baseline FDG‐PET scan was obtained after sitting motion‐less in the chair. In both stimulation paradigms, significantly increased FDG uptake was measured bilaterally in the medial part of Heschl's gyrus, with some overlap into the posterior insula. This is the first neuroimaging study to visualize cortical processing of natural vestibular stimuli. FDG uptake was demonstrated in the medial‐most part of Heschl's gyrus, normally associated with the primary auditory cortex. This anatomical localization seems plausible, considering that the labyrinth contains both the vestibular organ and the cochlea. [ABSTRACT FROM AUTHOR]
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- 2020
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369. Denver shunt in the treatment of refractory ascites in cirrhosis. A randomized controlled trial
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Jens Jacob Krintel, Helmer Ring-Larsen, Jens H. Henriksen, O Siemssen, and C Stadager
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medicine.medical_specialty ,Cirrhosis ,Hepatology ,Randomized controlled trial ,business.industry ,law ,Medicine ,Refractory ascites ,business ,medicine.disease ,Shunt (medical) ,Surgery ,law.invention - Published
- 1989
370. Laboratory study of aerosol settling velocities using Laser Doppler velocimetry.
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Jakobsen, Andreas Boes, Merrison, Jonathan, and Iversen, Jens Jacob
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LASER Doppler velocimetry , *KNUDSEN flow , *AEROSOLS , *FUSED silica , *DRAG (Aerodynamics) , *VELOCITY - Abstract
As a method to experimentally study aerodynamic drag the terminal settling velocities of aerosolized silica and glass microspheres (with sizes of 1–44 μm) have been measured at various gas pressures in the range 0.6–10 mbar and using various gas compositions including He, Ar, Xe, Air, CO 2 , and water vapour. Within the molecular scattering regime, i.e. where the Knudsen number Kn > 10 and up to 500, reasonable agreement has been found with the model of Epstein (1924). Values of the scattering parameter δ were observed to be within the expected range of 1–1.44 for respectively specular/evaporative - diffuse molecular scattering processes. However, δ was seen to depend upon gas composition, specifically for H 2 O; δ = 0.96 ± 0.07, CO 2 ; δ = 1.16 ± 0.07, noble gasses; δ = 1.25–1.44 and in the case of Air δ = 1.18 ± 0.07 which is not in agreement with that conventionally used of around 1.3–1.4. These observations imply disagreement with the concept of a general or universal model of drag for all particle surfaces and atmospheres. Similarly, for Kn < 10 these results were not well described by conventional models such as the semi-empirical expression of Knudsen-Weber (1911) or the general law of fall proposed by Millikan (1923b). Image 1 • Laser Doppler technique to measure microsphere settling velocities. • Agreement with Epstein's model within molecular drag regime. • Gas dependence of molecular scattering parameter. • Poor agreement with Millikan's law of fall. [ABSTRACT FROM AUTHOR]
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- 2019
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371. Quantifying the contact electrification of aerosolized insulating particles.
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Alois, Stefano, Merrison, Jonathan, Iversen, Jens Jacob, and Sesterhenn, Jörn
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VOLTA effect , *AEROSOLS , *INSULATING materials , *ELECTRONEGATIVITY , *SURFACE area - Abstract
The contact electrification of aerosolized micron-scale oxide particles has been investigated experimentally and the size and composition dependence determined. The net charge acquired by particles contacting the aerosolizer was seen to increase linearly with their surface area. A physically meaningful model based upon electron transfer has been applied leading to a predictive expression for the total particle surface charge concentration generated (σ) dependent on the absolute generalized relative electronegativity ( χ AGR ); σ = aχ AGR − b , where a = 4.7 e/μm 2 /V, b = −27 e/μm 2 and χ AGR is obtained by knowing the composition of the two contacting surfaces. The influence of relative humidity and particle cohesion on the contact electrification process was investigated. A maximum surface charge concentration of around 100 e/μm 2 was found, in agreement with previous work. [ABSTRACT FROM AUTHOR]
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- 2018
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372. Contact electrification in aerosolized monodispersed silica microspheres quantified using laser based velocimetry.
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Alois, Stefano, Merrison, Jonathan, Iversen, Jens Jacob, and Sesterhenn, Jörn
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ELECTRIFICATION , *VELOCIMETRY , *MICROSPHERES , *AEROSOLS , *SURFACE charges - Abstract
The contact electrification of aerosolized micro particles has been studied using a novel technique involving laser velocimetry. This has allowed the simultaneous determination of size and electrical charge of individual silica microspheres (in the range 1 – 8 µm). Interestingly the particles interacting with the injector tube have been seen to become electrified with a relatively narrow range of surface charge concentration of around Q/4πr 2 ~ −100 e - /µm 2 (~ −0.02 mC/m 2 ) for all particle sizes. Several combinations of aerosol particle and injector tube composition were also investigated, some of which led to positive particle electrification and all of which resulted in similar values of measured surface charge concentration. The electrification was not seen to be strongly affected by gas composition and is in reasonable agreement with the expected maximum surface charge observed in previous experiments (<0.1 mC/m 2 ). Possible explanations for this effect are discussed, including the possibility of field emission at the contact site. In the future this technique is intended also to be applied to particle-particle induced contact electrification and its material dependence. [ABSTRACT FROM AUTHOR]
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- 2017
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373. Development of the Bone Phenotype and microRNA Profile in Adults With Low‐Density Lipoprotein Receptor‐Related Protein 5–High Bone Mass (LRP5‐HBM) Disease
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Jens‐Jacob Lindegaard Lauterlein, Fatma Gossiel, Moritz Weigl, Richard Eastell, Matthias Hackl, Pernille Hermann, Jens Bollerslev, and Morten Frost
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HIGH BONE MASS ,HR‐pQCT ,LRP5 ,microRNA ,RARE MONOGENETIC BONE DISEASE ,Orthopedic surgery ,RD701-811 ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
ABSTRACT Pathogenic variants in the Wnt‐pathway co‐receptor low‐density lipoprotein (LDL) receptor‐related protein 5 (LRP5) cause high bone mass (LRP5‐HBM) due to insensitivity to the endogenous antagonist of Wnt‐signaling. Although indicating incessant progression of BMD and biomarkers reflecting bone formation, this has not been confirmed in individuals with LRP5‐HBM. We investigated how the LRP5‐HBM bone phenotype changes with age in adults and is associated with quantitative changes of bone turnover markers and bone‐related microRNAs (miRNAs) in the circulation. Whole body, lumbar spine, total hip, and femoral neck areal BMD (aBMD) and radial and tibial bone microarchitecture and geometry were assessed using DXA and HR‐pQCT scans of 15 individuals with LRP5‐HBMT253I (11 women; median age 51 years; range, 19 to 85 years) with a time interval between scans of 5.8 years (range, 4.9 to 7.6 years). Fasting P1NP and CTX were measured in 14 LRP5‐HBMT253I individuals and age‐, sex‐, and body mass index (BMI)‐matched controls, and 187 preselected miRNAs were quantified using qPCR in 12 individuals and age‐, sex‐, and BMI‐matched controls. DXA and HR‐pQCT scans were assessed in subjects who had reached peak bone mass (aged >25 years, n = 12). Femoral neck aBMD decreased by 0.8%/year (p = 0.01) and total hip by 0.3%/year, and radial volumetric BMD (vBMD) increased 0.3%/year (p = 0.03). Differences in bone turnover markers at follow‐up were not observed. Compared to controls, 11 of the 178 detectable miRNAs were downregulated and none upregulated in LRP5‐HBM individuals, and five of the downregulated miRNAs are reported to be involved in Wnt‐signaling. Bone loss at the hip in LRP5‐HBM individuals demonstrates that the bone phenotype does not uniformly progress with age. Differentially expressed miRNAs may reflect changes in the regulation of bone turnover and balance in LRP5‐HBM individuals. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.
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- 2021
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374. Cortical Activity During an Attack of Ménière's Disease—A Case Report
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Louise Devantier, Allan K. Hansen, Jens-Jacob Mølby-Henriksen, Michael Pedersen, Per Borghammer, Therese Ovesen, and Måns Magnusson
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case report ,Menière's disease ,neuroimaging ,PET ,cortical activity ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Background: Ménière's disease (MD) is a chronic peripheral vestibular disorder with recurrent episodes of vertigo accompanied by fluctuating hearing loss, tinnitus and aural fullness in the affected ear. There are several unanswered fundamental questions regarding MD, one of these being cortical activity during a MD attack. However, it is not possible to plan an investigation in an episodic disease as MD.Objective: To visualize cortical activity during an attack of MD.Method:18F-FDG PET scans were used to visualize cortical activity in a 62 years old male suffering from definite MD. Two 18F-FDG PET scans were performed. One to show activity during the attack and one to show normal baseline brain activity 7 days after the attack.Results: A number of low-magnitude fluctuations in the 18F-FDG FDG uptake were found in 18F-FDG PET examination following the MD attack compared to the patient's own baseline 18F-FDG FDG scan. Across both hemispheres no significant changes were seen. However, reduced activity was observed in most of the orbitofrontal, frontal cortices as well as Heschl's gyrus and insula.Conclusion: This is the first neuroimaging showing alteration of brain activity during an attack in a patient with MD. No strong focal alterations was seen. It is noteworthy that the decreased activity observed was in the insula and Heschl's gyrus that seems to be core areas for processing information from the labyrinth. It is also of interest that decreased activity rather than hyperactivity was observed.
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- 2021
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375. PET Visualized Stimulation of the Vestibular Organ in Menière's Disease
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Louise Devantier, Allan K. Hansen, Jens-Jacob Mølby-Henriksen, Christian Bech Christensen, Tina Lildal, Michael Pedersen, Måns Magnusson, Per Borghammer, and Therese Ovesen
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Menière's disease ,central vestibular system ,vestibular cortex ,positron emission tomography ,neuroimaging ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Introduction: The cortical metabolic activity in patients with Menière's disease has not been investigated. The aim of this study was to investigate the 18F-FDG cerebral uptake in Menière's patients compared to healthy controls.Method: Eight patients with right-sided Menière's disease and fourteen healthy controls underwent a video head impulse test (vHIT), test of utricular function with ocular vestibular evoked myogenic potentials (oVEMP) and three 18F-FDG-based PET examinations of the brain. Participants were seated in a self-propelled chair, injected with 18F-FDG and then exposed to 35 min of chair motion stimulation, followed by a PET scan. Two types of natural vestibular stimuli were applied, predominantly toward the right horizontal semicircular canal (angular acceleration) and right utriculus (linear acceleration). For baseline scans, participants were injected with 18F-FDG while seated without movement.Results: Analyses of baseline scans revealed decreased 18F-FDG-uptake in the medial part of Heschl's gyrus in the left hemisphere in patients with Menière's disease compared to healthy controls. During angular vestibular stimulation there was also a significantly decreased 18F-FDG uptake in the intersection between the medial part of Heschl's gyrus and the parietal operculum in the left hemisphere and bilaterally in the posterior part of insula. During linear stimulation, Menière's patients showed decreased 18F-FDG uptake in the medial part of Heschl's gyrus in the right hemisphere and also bilaterally in the posterior insula. In addition, decreased 18F-FDG uptake was seen in the thalamus during vestibular stimulation.Conclusion: Heschl's gyrus, the posterior part of insula, and thalamus have previously been shown to be core areas for processing vestibular inputs. Patients with Menière's disease solely differed from the healthy controls with lower cortical activity in these areas at baseline and during natural vestibular stimulation.
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- 2020
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376. Obesity-Associated Hypermetabolism and Accelerated Senescence of Bone Marrow Stromal Stem Cells Suggest a Potential Mechanism for Bone Fragility
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Michaela Tencerova, Morten Frost, Florence Figeac, Tina Kamilla Nielsen, Dalia Ali, Jens-Jacob Lindegaard Lauterlein, Thomas Levin Andersen, Anders Kristian Haakonsson, Alexander Rauch, Jonna Skov Madsen, Charlotte Ejersted, Kurt Højlund, and Moustapha Kassem
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Biology (General) ,QH301-705.5 - Abstract
Summary: Obesity is associated with increased risk for fragility fractures. However, the cellular mechanisms are unknown. Using a translational approach combining RNA sequencing and cellular analyses, we investigated bone marrow stromal stem cells (BM-MSCs) of 54 men divided into lean, overweight, and obese groups on the basis of BMI. Compared with BM-MSCs obtained from lean, obese BM-MSCs exhibited a shift of molecular phenotype toward committed adipocytic progenitors and increased expression of metabolic genes involved in glycolytic and oxidoreductase activity. Interestingly, compared with paired samples of peripheral adipose tissue-derived stromal cells (AT-MSCs), insulin signaling of obese BM-MSCs was enhanced and accompanied by increased abundance of insulin receptor positive (IR+) and leptin receptor positive (LEPR+) cells in BM-MSC cultures. Their hyper-activated metabolic state was accompanied by an accelerated senescence phenotype. Our data provide a plausible explanation for the bone fragility in obesity caused by enhanced insulin signaling leading to accelerated metabolic senescence of BM-MSCs. : Tencerova et al. show that in human obesity, BM-MSCs exhibit a hypermetabolic state defined by upregulation of insulin signaling with enhanced adipogenesis and increased intracellular reactive oxygen species (ROS), leading to a senescence bone microenvironment contributing to bone fragility. Moreover, increased abundance of IR+ and LEPR+ BM-MSCs is characteristic of this phenotype, with an activated metabolic rate in obese subjects. Keywords: obesity, skeletal fragility, bone marrow skeletal stem cells, adipose-derived stem cells, differentiation potential, adipogenesis, insulin signaling
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- 2019
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377. Optimizing selectivity of anion hydrophobic multimodal chromatography for purification of a single‐chain variable fragment.
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Sakhnini, Laila I., Pedersen, Anja K., León, Ileana Rodríguez, Greisen, Per J., Hansen, Jens Jacob, Vester‐Christensen, Malene B., Bülow, Leif, and Dainiak, Maria B.
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CHROMATOGRAPHIC analysis , *ANIONS , *SURFACE properties , *PROTEIN fractionation , *LIQUID chromatography-mass spectrometry , *EXPERIMENTAL design , *PROTEOMICS - Abstract
Single‐chain variable fragments (scFv) are widely used in several fields. However, they can be challenging to purify unless using expensive Protein L‐based affinity adsorbents or affinity tags. In this work, a purification process for a scFv using mixed‐mode (MM) chromatography was developed by design of experiments (DoE) and proteomics for host cell protein (HCP) quantification. Capture of scFv from human embryonic kidney 293 (HEK293) cell feedstocks was performed by hydrophobic charge induction chromatography (MEP HyperCel™), whereafter polishing was performed by anion hydrophobic MM chromatography (Capto Adhere™). The DoE designs of the polishing step included both binding and flow‐through modes, the latter being the standard mode for HCP removal. Chromatography with Capto Adhere™ in binding‐mode with elution by linear salt gradient at pH 7.5 resulted in optimal yield, purity and HCP reduction factor of 98.9 > 98.5%, and 14, respectively. Totally, 258 different HCPs were removed, corresponding to 84% of identified HCPs. The optimized conditions enabled binding of the scFv to Capto Adhere™ below its theoretical pI, while the majority of HCPs were in the flow‐through. Surface property maps indicated the presence of hydrophobic patches in close proximity to negatively charged patches that could potentially play a role in this unique selectivity. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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378. MarsTEM sensor simulations in Martian dust environment.
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Colombatti, Giacomo, Bettanini, Carlo, Aboudan, Alessio, Debei, Stefano, Esposito, Francesca, Molfese, Cesare, Cecere, Anselmo, Merrison, John, and Iversen, Jens Jacob
- Subjects
- *
MARTIAN surface , *TESTING of wind tunnels , *COMPUTER simulation , *TEMPERATURE sensors - Abstract
A wind tunnel test campaign has been conducted prior to the landing of the Exomars2016 EDM module on the Meridiani Planum on the 19th of October 2016. Test were performed in the Mars wind tunnel facility at Aahrus University (DK) under the 2015 Europlanet Call. The facility was available for a 5 days campaign where different environmental configurations were tested and both a full scale DREAMS (Dust Characterisation, Risk Assessment, and Environment Analyser on the Martian Surface) Metmast model and a Descent Module mockup were studied. In particular the MarsTEM (Mars TEMperature sensor), the temperature sensor of the DREAMS package onboard Exomars2016, was studied for different wind velocities and directions, effect of light sources and presence of dust. The test showed that the sensor response is dependent on wind direction but only slightly on wind velocities. It also seems that the presence of the dust in the wind and the consequent dust deposit on the Metmast and the sensor itself uniforms the response for different wind velocities and directions. Light is also affecting the measurements but it is still not so clear what will be the effect on Mars due to the particular light sources used for the test. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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379. Suppression head impulse paradigm in healthy adolescents – A novel variant of the head impulse test.
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Devantier, Louise, Hoskison, Emma, Ovesen, Therese, and Henriksen, Jens-Jacob MØlby
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- *
HUMAN research subjects , *TEENAGERS , *VESTIBULAR function tests , *SACCADIC eye movements , *EXAMINERS (Education) - Abstract
BACKGROUND: Suppression Head Impulse Paradigm (SHIMP), a novel variant of the Head Impulse Test has been introduced. At the same time, the Head Impulse Test was renamed to the Head Impulse Paradigm (HIMP). Contrary to HIMP saccades, SHIMP saccades are a sign of vestibular function. OBJECTIVE: 1) To compare SHIMP and HIMP feasibility, vestibular-ocular reflex (VOR) gain value and the saccadic pattern in healthy adolescents. 2) To compare SHIMP and HIMP feasibility in the hands of an experienced and an inexperienced HIMP examiner. METHOD: A total of 29 adolescents from Skåde Municipal School, Denmark were tested with HIMP and then with SHIMP. RESULTS: Neither covert nor overt saccades were observed in the HIMP, whereas SHIMP saccades were observed in all SHIMP reports. SHIMP gain values were statistically lower than HIMP gain values. A statistically significant difference was observed between the two examiners' right SHIMP gain values, but not for the left SHIMP gain values or the HIMP gain values. CONCLUSIONS: We found that HIMP and SHIMP tests are feasible in healthy adolescents for experienced as well as inexperienced examiners. However, one must be aware of potential pitfalls in the execution and interpretation of both tests. This is a well-known fact for the HIMP test, but additional considerations are needed to obtain reliable results from the SHIMP test. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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380. The Use of Computer-Assisted Home Exercises to Preserve Physical Function after a Vestibular Rehabilitation Program: A Randomized Controlled Study
- Author
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Michael Smaerup, Uffe Laessoe, Eric Grönvall, Jens-Jacob Henriksen, and Else Marie Damsgaard
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Medicine (General) ,R5-920 - Abstract
Objective. The purpose of this study was to evaluate whether elderly patients with vestibular dysfunction are able to preserve physical functional level, reduction in dizziness, and the patient’s quality of life when assistive computer technology is used in comparison with printed instructions. Materials and Methods. Single-blind, randomized, controlled follow-up study. Fifty-seven elderly patients with chronic dizziness were randomly assigned to a computer-assisted home exercise program or to home exercises as described in printed instructions and followed for tree month after discharge from an outpatient clinic. Results. Both groups had maintained their high functional levels three months after finishing the outpatient rehabilitation. No statistically significant difference was found in outcome scores between the two groups. In spite of moderate compliance levels, the patients maintained their high functional level indicating that the elderly should not necessarily exercise for the first three months after termination of the training in the outpatient clinic. Conclusion. Elderly vestibular dysfunction patients exercising at home seem to maintain their functional level, level of dizziness, and quality of life three months following discharge from hospital. In this specific setup, no greater effect was found by introducing a computer-assisted training program, when compared to standard home training guided by printed instructions. This trial is registered with NCT01344408.
- Published
- 2016
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381. Designing monoclonal antibody fragment-based affinity resins with high binding capacity by thiol-directed immobilisation and optimisation of pore/ligand size ratio.
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Sakhnini, Laila Ismail, Pedersen, Anja Kallesøe, Ahmadian, Haleh, Hansen, Jens-Jacob, Bülow, Leif, and Dainiak, Maria
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- *
MONOCLONAL antibodies , *LIGAND binding (Biochemistry) , *ENCAPSULATION (Catalysis) , *PORE size (Materials) , *STERIC hindrance - Abstract
Monoclonal antibody (mAb) based affinity resins usually suffer from low binding capacity, most probably as a result of steric hindrance by the large 150 kDa size of the mAb and a random immobilisation approach. The present work investigates the influence of a variety of factors on dynamic binding capacity (DBC) such as pore/ligand size ratio, accessibility of ligand and ligand density. The effect of pore/ligand size ratio was investigated using Fab and scFv fragments on various resins with different pore sizes. The accessibility of the ligand was investigated by a site-directed immobilisation approach, where three C-terminal tags, PPKPPK, FLAG™ and Cys, were introduced into the Fab fragments for immobilisation on resins via amino-, carboxyl- and thiol-groups, respectively. The scFv fragments were tagged at the C-terminal only with FLAG™ to enable a straight forward purification procedure, and were immobilised to resins via amino- and carboxyl-groups. The target protein had a molecular weight (MW) of 50 kDa. A 3-fold higher dynamic binding capacity at 100% breakthrough (DBC 100% ) was observed for Fab wild-type (wt) on CNBr-activated Sepharose 4 FF relative to mAb on same resin at the same ligand density. However, no major difference in DBC 100% was observed between Fab wt and scFv immobilised on CNBr-activated Sepharose 4 FF at the same ligand density. Thus, further increase of pore/ligand size ratio from Fab to scFv on a resin with average pore size of 300 Å, did not seem to be beneficial. Among the tested tags, only the C-terminal Cys tag proved to site-direct the ligands during immobilisation as it allowed the DBC 100% to increase 1.6-fold as compared to Fab wt immobilised via amino-groups on CNBr-activated Sepharose 4 FF and Actigel ALD Superflow at the same ligand density. The influence of ligand density was investigated by selecting immobilised Fab Cys on Sulfhydryl-reactive resin. Increasing ligand density from 0.103 to 0.202 μmol/mL resulted in the same utilisation yield (82–85%), whereas a further increase in ligand density from 0.202 to 0.328 μmol/mL resulted in a 20%-unit decrease in utilisation yield and less steep breakthrough curve, suggesting steric hindrance in the pores of the resin. In addition, site-directed affinity ligands resulted in a more pronounced, sigmoid-shaped breakthrough curve, leading to more efficient use of capacity. The highest DBC 100% was obtained for Fab Cys on Sulfhydryl-reactive resin and scFv on Actigel ALD Superflow; 11 mg/mL and 10 mg/mL, respectively, as compared to the DBC 100% of 0.8 mg/mL for mAb on CNBr-activated Sepharose 4 FF. Pore/ligand size ratio of 3, which was achieved for Fab ligands on the studied resins, was shown to be feasible for capturing a protein in MW of 50 kDa. Totally, a 13.8-fold improvement in DBC 100% was achieved with the Fab-based affinity resin coupled via the C-terminal Cys as compared to the mAb-based affinity resin. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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382. MarsTEM sensor simulations in Martian dust environment
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Giacomo Colombatti, Alessio Aboudan, C. Bettanini, J. J. Iversen, Cesare Molfese, John Merrison, Anselmo Cecere, Francesca Esposito, Stefano Debei, ITA, DNK, Colombatti, Giacomo, Bettanini, Carlo, Aboudan, Alessio, Debei, Stefano, Esposito, Francesca, Molfese, Cesare, Cecere, Anselmo, Merrison, John, and Iversen, Jens Jacob
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Meridiani Planum ,010504 meteorology & atmospheric sciences ,Meteorology ,Full scale ,01 natural sciences ,Exomars2016 ,Martian surface ,0103 physical sciences ,Electrical and Electronic Engineering ,DREAMS ,010303 astronomy & astrophysics ,Instrumentation ,MarsTEM ,Wind tunnel chamber ,DREAMS, Exomars2016, MarsTEM, Wind tunnel chamber, Instrumentation, Electrical and Electronic Engineering ,0105 earth and related environmental sciences ,Wind tunnel ,Martian ,Applied Mathematics ,Mars Exploration Program ,Wind direction ,Condensed Matter Physics ,13. Climate action ,Mockup ,Environmental science - Abstract
A wind tunnel test campaign has been conducted prior to the landing of the Exomars2016 EDM module on the Meridiani Planum on the 19th of October 2016. Test were performed in the Mars wind tunnel facility at Aahrus University (DK) under the 2015 Europlanet Call. The facility was available for a 5 days campaign where different environmental configurations were tested and both a full scale DREAMS (Dust Characterisation, Risk Assessment, and Environment Analyser on the Martian Surface) Metmast model and a Descent Module mockup were studied. In particular the MarsTEM (Mars TEMperature sensor), the temperature sensor of the DREAMS package onboard Exomars2016, was studied for different wind velocities and directions, effect of light sources and presence of dust. The test showed that the sensor response is dependent on wind direction but only slightly on wind velocities. It also seems that the presence of the dust in the wind and the consequent dust deposit on the Metmast and the sensor itself uniforms the response for different wind velocities and directions. Light is also affecting the measurements but it is still not so clear what will be the effect on Mars due to the particular light sources used for the test.
- Published
- 2018
383. Laboratory studies of aeolian sediment transport processes on planetary surfaces
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Keld Rømer Rasmussen, Jonathan Merrison, Alexandre Valance, Department of Earth Sciences [Aarhus], Aarhus University [Aarhus], Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Department of Physics and Astronomy [Aarhus], We acknowledge Andreas Boes Jakobsen and Jens Jacob Iversen for their help and support with the experimental work in the Aarhus wind tunnel. We would like to thank Pascal Dupont, Ahmed Ould El Mochtar, and Marc Lämmel for fruitful discussion during the workshop ‘Fluid-Mediated Particle Transport in Geophysical Flows’, 2013-09-23 to 2013-12-20 at the Kavli Institute, UCSB. Marc Lämmel also derived Fig. 17B from our experimental data. We also acknowledge two anonymous reviewers for the valuable comments and suggestions., and Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
splash ,Dust detachment ,010504 meteorology & atmospheric sciences ,Saltation ,Splash ,010502 geochemistry & geophysics ,01 natural sciences ,Aeolian laboratory studies ,Shields parameter ,Wind speed ,ripple spacing ,Particle tracking velocimetry ,Saltation (geology) ,saltation ,Particle velocity ,Shear velocity ,Particle trajectory ,Geomorphology ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Wind tunnel ,Mechanics ,Ripple spacing ,dust detachment ,particle trajectory ,Aeolian processes ,[PHYS.COND.CM-SCM]Physics [physics]/Condensed Matter [cond-mat]/Soft Condensed Matter [cond-mat.soft] ,Geology - Abstract
International audience; We review selected experimental saltation studies performed in laboratory wind tunnels and collision experiments performed in (splash-) laboratory facilities that allow detailed observations between impinging particles on a stationary bed.We also discuss progress in understanding aeolian transport in nonterrestrial environments. Saltation studies in terrestrial wind tunnels can be divided into two groups. The first group comprises studies using a short test bed, typically 1–4m long, and focuses on the transitional behavior near the upwind roughness discontinuity where saltation starts. The other group focuses on studies using long test beds — typically 6 m or more — where the saturated saltation takes place under equilibrium conditions between wind flow and the underlying rough bed. Splash studies using upscaled model experiments allow collision simulations with large spherical particles to be recorded with a high speed video camera. The findings indicate that the number of ejected particles per impact scales linearlywith the impact velocity of the saltating particles. Studies of saturated saltation in several facilities using predominantly Particle Tracking Velocimetry or Laser Doppler Velocimetry indicate that the velocity of the (few) particles having high trajectories increases with increasing friction velocity. However, the speed of the majority of particles that do not reachmuch higher than Bagnold's focal point is virtually independent of Shields parameter—at least for lowor intermediate u⁎-values. In this case mass flux depends on friction velocity squared and not cubed as originally suggested by Bagnold. Over short beds particle velocity shows stronger dependence on friction velocity and profiles of particle velocity deviate from those obtained over long beds. Measurements using horizontally segmented traps give average saltation jump-lengths near 60–70 mm and appear to be only weakly dependent on friction velocity, which is in agreement with some, but not all, older or recent wind tunnel observations. Similarly some measurements performed with uniform sand samples having grain diameters of the order of 0.25–0.40mmindicate that ripple spacing depends on friction velocity in a similar way as particle jump length. The observations are thus in agreementwith a recent ripple model that link the typical jump length to ripple spacing. A possible explanation for contradictory observations in some experiments may be that long observation sequences are required in order to assure that equilibrium exists between ripple geometry and wind flow.Quantitative understanding of saltation characteristics onMars still lacks important elements. Based upon image analysis and numerical predictions, aeolian ripples have been thought to consist of relatively large grains (diameter N 0.6mm) and that saltation occurs at high wind speeds (N26 m/s) involving trajectories that are significantly longer than those on Earth (by a factor of 10–100). However, this is not supported by recent observations from the surface of Mars, which shows that active ripples in their geometry and composition have characteristics compatible with those of terrestrial ripples (Sullivan et al., 2008). Also the highest average wind speeds on Mars have been measured to be b20 m/s, with even turbulent gusts not exceeding 25 m/s. Electrification is seen as a dominant factor in the transport dynamics of dust onMars, affecting the structure, adhesive properties and detachment/entrainment mechanisms specifically through the formation of aggregates (Merrison et al., 2012). Conversely for terrestrial conditions electric fields typically observed are not intense enough to significantly affect sand transport rates while little is known in the case of extra-terrestrial environments.
- Published
- 2015
384. Hantavirus infections in forestry workers
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Bjedov, Linda, Margaletić, Josip, Vucelja, Marko, Miletić-Medved, Marica, Matijević, Ivana, Cvetko Krajinović, Lidija, Markotić, Alemka, Jens, Jacob, and Alexandra, Esther
- Subjects
lcsh:Agriculture ,Puumala hantavirus ,rodents ,lcsh:Botany ,forestry workers ,lcsh:S ,bank vole ,Dobrava-Belgrade hantavirus ,lcsh:QK1-989 - Abstract
Forestry workers are exposed to wild animals, vegetation and soil, which may contain pathogens harmful to humans. Infection can have different pathways from inhalation, direct contact and vector-borne inoculation through the skin injuries. The aim of our study was to determine infection rates in forestry workers caused by different rodent-borne hantaviruses (HTV) in the central Posavina region, Croatia. We tested sera of 295 forestry workers for the presence of specific IgG antibodies for Puumala, Dobrava-Belgrade and Hantaan. Additionally at two different locations also in Posavina region 105 wild rodents were trapped and tested for HTV using direct fluorescence antibody test. Only bank voles were screened for presence of PUU N antigen using Western blot method. Nova Gradiška and Slavonski Brod are - known as endemic regions for HTV. However, the high HTV seroprevalence of foresters (16.3%) was unexpected. 11.2 % of forestry workers were infected with Puumala hantavirus (PUUV) and 4.4% with Dobrava-Belgrade hantavirus (DOBV) and rest of 0.7% were positive for both viruses. Overall 14% of rodents trapped on two locations were tested positive for HTV. In lungs of 26.3% of bank voles virus antigen was detected. Such high infection rates in forestry workers show how important is to monitor rodent populations and to analyze prevalence of particular rodent born zoonoses.
- Published
- 2011
385. The functional role of the autolysis loop in the regulation of factor X upon hemostatic response.
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Bonde AC, Lund J, Hansen JJ, Winther JR, Nielsen PF, Zahn S, Tiainen P, Olsen OH, Petersen HH, and Bjelke JR
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- Factor Va chemistry, Factor Xa metabolism, Humans, Prothrombin chemistry, Thromboplastin genetics, Thromboplastin metabolism, Factor X chemistry
- Abstract
Background: The regulation of factor X (FX) is critical to maintain the balance between blood coagulation and fluidity., Objectives: To functionally characterize the role of the FX autolysis loop in the regulation of the zymogen and active form of FX., Methods: We introduced novel N-linked glycosylations on the surface-exposed loop spanning residues 143-150 (chymotrypsin numbering) of FX. The activity and inhibition of recombinant FX variants was quantified in pure component assays. The in vitro thrombin generation potential of the FX variants was evaluated in FX-depleted plasma., Results: The factor VIIa (FVIIa)-mediated activation and prothrombin activation was reduced, presumably through steric hinderance. Prothrombin activation was, however, recovered in presence of cofactor factor Va (FVa) despite a reduced prothrombinase assembly. The introduced N-glycans exhibited position-specific effects on the interaction with two FXa inhibitors: tissue factor pathway inhibitor (TFPI) and antithrombin (ATIII). K
i for the inhibition by full-length TFPI of these FXa variants was increased by 7- to 1150-fold, whereas ATIII inhibition in the presence of the heparin-analog Fondaparinux was modestly increased by 2- to 15-fold compared with wild-type. When supplemented in zymogen form, the FX variants exhibited reduced thrombin generation activity relative to wild-type FX, whereas enhanced procoagulant activity was measured for activated FXa variants., Conclusion: The autolysis loop participates in all aspects of FX regulation. In plasma-based assays, a modest decrease in FX activation rate appeared to knock down the procoagulant response even when down regulation of FXa activity by inhibitors was reduced., (© 2021 International Society on Thrombosis and Haemostasis.)- Published
- 2022
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386. Development of the Bone Phenotype and microRNA Profile in Adults With Low-Density Lipoprotein Receptor-Related Protein 5-High Bone Mass (LRP5-HBM) Disease.
- Author
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Lauterlein JL, Gossiel F, Weigl M, Eastell R, Hackl M, Hermann P, Bollerslev J, and Frost M
- Abstract
Pathogenic variants in the Wnt-pathway co-receptor low-density lipoprotein (LDL) receptor-related protein 5 (LRP5) cause high bone mass (LRP5-HBM) due to insensitivity to the endogenous antagonist of Wnt-signaling. Although indicating incessant progression of BMD and biomarkers reflecting bone formation, this has not been confirmed in individuals with LRP5-HBM. We investigated how the LRP5-HBM bone phenotype changes with age in adults and is associated with quantitative changes of bone turnover markers and bone-related microRNAs (miRNAs) in the circulation. Whole body, lumbar spine, total hip, and femoral neck areal BMD (aBMD) and radial and tibial bone microarchitecture and geometry were assessed using DXA and HR-pQCT scans of 15 individuals with LRP5-HBM
T253I (11 women; median age 51 years; range, 19 to 85 years) with a time interval between scans of 5.8 years (range, 4.9 to 7.6 years). Fasting P1NP and CTX were measured in 14 LRP5-HBMT253I individuals and age-, sex-, and body mass index (BMI)-matched controls, and 187 preselected miRNAs were quantified using qPCR in 12 individuals and age-, sex-, and BMI-matched controls. DXA and HR-pQCT scans were assessed in subjects who had reached peak bone mass (aged >25 years, n = 12). Femoral neck aBMD decreased by 0.8%/year ( p = 0.01) and total hip by 0.3%/year, and radial volumetric BMD (vBMD) increased 0.3%/year ( p = 0.03). Differences in bone turnover markers at follow-up were not observed. Compared to controls, 11 of the 178 detectable miRNAs were downregulated and none upregulated in LRP5-HBM individuals, and five of the downregulated miRNAs are reported to be involved in Wnt-signaling. Bone loss at the hip in LRP5-HBM individuals demonstrates that the bone phenotype does not uniformly progress with age. Differentially expressed miRNAs may reflect changes in the regulation of bone turnover and balance in LRP5-HBM individuals. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research., Competing Interests: MH and MW report personal fees from TAmiRNA GmbH, outside the submitted work. RE reports grants from Amgen, grants and personal fees from IDS, grants from Alexion, grants and personal fees from Roche, personal fees from GSK Nutrition, personal fees from Mereo, personal fees from Sandoz, grants and personal fees from Nittobo, personal fees from AbbVie, personal fees from Samsung, personal fees from Haoma Medica, personal fees from Elsevier, personal fees from CL Bio, personal fees from FNIH, personal fees from Viking, personal fees from UCSF, personal fees from Biocon, from Lyramid, outside the submitted work., (© 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.)- Published
- 2021
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387. Cortical Activity During an Attack of Ménière's Disease-A Case Report.
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Devantier L, Hansen AK, Mølby-Henriksen JJ, Pedersen M, Borghammer P, Ovesen T, and Magnusson M
- Abstract
Background: Ménière's disease (MD) is a chronic peripheral vestibular disorder with recurrent episodes of vertigo accompanied by fluctuating hearing loss, tinnitus and aural fullness in the affected ear. There are several unanswered fundamental questions regarding MD, one of these being cortical activity during a MD attack. However, it is not possible to plan an investigation in an episodic disease as MD. Objective: To visualize cortical activity during an attack of MD. Method:
18 F-FDG PET scans were used to visualize cortical activity in a 62 years old male suffering from definite MD. Two18 F-FDG PET scans were performed. One to show activity during the attack and one to show normal baseline brain activity 7 days after the attack. Results: A number of low-magnitude fluctuations in the18 F-FDG FDG uptake were found in18 F-FDG PET examination following the MD attack compared to the patient's own baseline18 F-FDG FDG scan. Across both hemispheres no significant changes were seen. However, reduced activity was observed in most of the orbitofrontal, frontal cortices as well as Heschl's gyrus and insula. Conclusion: This is the first neuroimaging showing alteration of brain activity during an attack in a patient with MD. No strong focal alterations was seen. It is noteworthy that the decreased activity observed was in the insula and Heschl's gyrus that seems to be core areas for processing information from the labyrinth. It is also of interest that decreased activity rather than hyperactivity was observed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Devantier, Hansen, Mølby-Henriksen, Pedersen, Borghammer, Ovesen and Magnusson.)- Published
- 2021
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388. A lower-than-expected saltation threshold at Martian pressure and below.
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Andreotti B, Claudin P, Iversen JJ, Merrison JP, and Rasmussen KR
- Abstract
Aeolian sediment transport is observed to occur on Mars as well as other extraterrestrial environments, generating ripples and dunes as on Earth. The search for terrestrial analogs of planetary bedforms, as well as environmental simulation experiments able to reproduce their formation in planetary conditions, are powerful ways to question our understanding of geomorphological processes toward unusual environmental conditions. Here, we perform sediment transport laboratory experiments in a closed-circuit wind tunnel placed in a vacuum chamber and operated at extremely low pressures to show that Martian conditions belong to a previously unexplored saltation regime. The threshold wind speed required to initiate saltation is only quantitatively predicted by state-of-the art models up to a density ratio between grain and air of [Formula: see text] but unexpectedly falls to much lower values for higher density ratios. In contrast, impact ripples, whose emergence is continuously observed on the granular bed over the whole pressure range investigated, display a characteristic wavelength and propagation velocity essentially independent of pressure. A comparison of these findings with existing models suggests that sediment transport at low Reynolds number but high grain-to-fluid density ratio may be dominated by collective effects associated with grain inertia in the granular collisional layer., Competing Interests: The authors declare no competing interest.
- Published
- 2021
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389. How comorbidities impact Early Warning Score as a predictor of 7-day mortality.
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Langsted SND, Dynesen JJ, Liesanth JY, Jessen MK, Mackenhauer J, Ahrensberg J, and Kirkegaard H
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- Adult, Aged, Cohort Studies, Comorbidity, Denmark, Female, Humans, Male, Middle Aged, Outcome Assessment, Health Care, Risk Assessment, Risk Factors, Critical Illness mortality, Early Warning Score, Health Status Indicators, Hospital Mortality
- Abstract
Background: Early Warning Score systems are used to monitor patients at risk of deterioration. How comorbidities impact Early Warning Score's ability to predict short-term mortality in the emergency department is not fully elucidated. The aim of the study was to investigate how comorbidities impact Early Warning Score as predictor of 7-day mortality., Methods: This is an observational cohort study of adult emergency department patients attending one of the five emergency departments in Central Region Denmark from 1 March 2015 to 31 May 2015. Charlson Comorbidity Index was used as a measure of comorbidities. Logistic regression was used to calculate the odds ratio for 7-day mortality. Patients were compared in three groups: Charlson Comorbidity Index: 0, 1-2, 3+., Results: A total of 30 060 adult patients attended one of the five emergency departments. Nineteen thousand one hundred twenty-three patients were included. Charlson Comorbidity Index 3+ patients presenting with Early Warning Score 0, 1-2 or 3-4 had significantly higher odds ratio of 7-day mortality compared to Charlson Comorbidity Index 0 patients with equal Early Warning Score. For patients with Early Warning Score 5+, Charlson Comorbidity Index -status had no significant impact on 7-day mortality after adjusting for age., Conclusion: In patients presenting with lower acuity (Early Warning Score 0-4) Charlson Comorbidity Index has a significant impact on 7-day mortality regardless of Early Warning Score. Including Charlson Comorbidity Index status in Early Warning Score or adjusting for Charlson Comorbidity Index -status could increase the predictive value of Early Warning Score in predicting 7-day mortality.
- Published
- 2020
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390. PET Visualized Stimulation of the Vestibular Organ in Menière's Disease.
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Devantier L, Hansen AK, Mølby-Henriksen JJ, Christensen CB, Lildal T, Pedersen M, Magnusson M, Borghammer P, and Ovesen T
- Abstract
Introduction: The cortical metabolic activity in patients with Menière's disease has not been investigated. The aim of this study was to investigate the
18 F-FDG cerebral uptake in Menière's patients compared to healthy controls. Method: Eight patients with right-sided Menière's disease and fourteen healthy controls underwent a video head impulse test (vHIT), test of utricular function with ocular vestibular evoked myogenic potentials (oVEMP) and three18 F-FDG-based PET examinations of the brain. Participants were seated in a self-propelled chair, injected with18 F-FDG and then exposed to 35 min of chair motion stimulation, followed by a PET scan. Two types of natural vestibular stimuli were applied, predominantly toward the right horizontal semicircular canal (angular acceleration) and right utriculus (linear acceleration). For baseline scans, participants were injected with18 F-FDG while seated without movement. Results: Analyses of baseline scans revealed decreased18 F-FDG-uptake in the medial part of Heschl's gyrus in the left hemisphere in patients with Menière's disease compared to healthy controls. During angular vestibular stimulation there was also a significantly decreased18 F-FDG uptake in the intersection between the medial part of Heschl's gyrus and the parietal operculum in the left hemisphere and bilaterally in the posterior part of insula. During linear stimulation, Menière's patients showed decreased18 F-FDG uptake in the medial part of Heschl's gyrus in the right hemisphere and also bilaterally in the posterior insula. In addition, decreased18 F-FDG uptake was seen in the thalamus during vestibular stimulation. Conclusion: Heschl's gyrus, the posterior part of insula, and thalamus have previously been shown to be core areas for processing vestibular inputs. Patients with Menière's disease solely differed from the healthy controls with lower cortical activity in these areas at baseline and during natural vestibular stimulation., (Copyright © 2020 Devantier, Hansen, Mølby-Henriksen, Christensen, Lildal, Pedersen, Magnusson, Borghammer and Ovesen.)- Published
- 2020
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391. Improving the Developability of an Antigen Binding Fragment by Aspartate Substitutions.
- Author
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Sakhnini LI, Greisen PJ, Wiberg C, Bozoky Z, Lund S, Wolf Perez AM, Karkov HS, Huus K, Hansen JJ, Bülow L, Lorenzen N, Dainiak MB, and Pedersen AK
- Subjects
- Amino Acid Substitution, Animals, Antigens immunology, Computer Simulation, HEK293 Cells, Humans, Immunoglobulin Fab Fragments genetics, Immunoglobulin Fab Fragments immunology, Mice, Peptide Library, Protein Multimerization genetics, Protein Stability, Aspartic Acid chemistry, Immunoglobulin Fab Fragments chemistry
- Abstract
Aggregation can be a major challenge in the development of antibody-based pharmaceuticals as it can compromise the quality of the product during bioprocessing, formulation, and drug administration. To avoid aggregation, developability assessment is often run in parallel with functional optimization in the early screening phases to flag and deselect problematic molecules. As developability assessment can be demanding with regard to time and resources, there is a high focus on the development of molecule design strategies for engineering molecules with a high developability potential. Previously, Dudgeon et al. [(2012) Proc. Natl. Acad. Sci. U. S. A. 109, 10879-10884] demonstrated how Asp substitutions at specific positions in human variable domains and single-chain variable fragments could decrease the aggregation propensity. Here, we have investigated whether these Asp substitutions would improve the developability potential of a murine antigen binding fragment (Fab). A full combinatorial library consisting of 393 Fab variants with single, double, and triple Asp substitutions was first screened in silico with Rosetta; thereafter, 26 variants with the highest predicted thermodynamic stability were selected for production. All variants were subjected to a set of developability studies. Interestingly, most variants had thermodynamic stability on par with or improved relative to that of the wild type. Twenty-five of the variants exhibited improved nonspecificity. Half of the variants exhibited improved aggregation resistance. Strikingly, while we observed remarkable improvement in the developability potential, the Asp substitutions had no substantial effect on the antigenic binding affinity. Altogether, by combining the insertion of negative charges and the in silico screen based on computational models, we were able to improve the developability of the Fab rapidly.
- Published
- 2019
- Full Text
- View/download PDF
392. [Diabetes and hearing impairment due to mitochondrial mutation].
- Author
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Lauterlein JJ, Olsen I, Yderstræde K, and Nielsen MF
- Subjects
- Deafness complications, Diabetes Mellitus, Type 2 complications, Female, Genetic Predisposition to Disease, Humans, MELAS Syndrome complications, Magnetic Resonance Imaging, Male, Middle Aged, Pedigree, Young Adult, DNA, Mitochondrial genetics, Deafness genetics, Diabetes Mellitus, Type 2 genetics, MELAS Syndrome genetics
- Abstract
Mutations in the mitochondrial genome can cause mitochondrial diabetes. We present two cases in which the same mutation, mtDNA3243A>G, caused two different phenotypes: maternally inherited diabetes and deafness and mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes. Mitochondrial disease can imitate a variety of common con-ditions and should be considered in the case of multisystem disease, complex neurological symptoms or neurological symptoms combined with symptoms of other organ systems.
- Published
- 2014
393. [Extended medical education--at any cost?].
- Author
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Manhem S, Bunne J, Fredriksson JJ, Karim H, Nyberg G, Nyman A, Sturm A, and Nylander A
- Subjects
- Clinical Clerkship, Clinical Competence standards, Sweden, Education, Medical economics, Education, Medical organization & administration, Education, Medical standards
- Published
- 2011
394. Similar recovery rates of Fusobacterium necrophorum from recurrently infected and non-infected tonsils.
- Author
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Klug TE, Henriksen JJ, Fuursted K, and Ovesen T
- Subjects
- Adolescent, Adult, Child, Female, Fusobacterium Infections surgery, Fusobacterium necrophorum pathogenicity, Humans, Male, Prospective Studies, Recurrence, Statistics, Nonparametric, Tonsillitis microbiology, Tonsillitis surgery, Treatment Outcome, Young Adult, Fusobacterium Infections pathology, Fusobacterium necrophorum isolation & purification, Palatine Tonsil microbiology, Tonsillectomy, Tonsillitis pathology
- Abstract
Introduction: Recent studies implicate the presence of Fusobacterium necrophorum (FN) in recurrent tonsillitis (RT), acute tonsillitis and peritonsillar abscess. The objective of the present study was to determine whether FN plays a role in RT by comparing bacteriologic results from patients suffering from RT, tonsillar hypertrophy and halitosis or persistent sore throat syndrome (PSTS). We analyzed both tonsils to determine the degree of concordance., Material and Methods: A prospective study was conducted in 80 patients aged 8-30 years who were undergoing elective tonsillectomy. The patients were divided into four groups according to indication for surgery. Aerobic and anaerobic cultures from the tonsillar surface and core were analyzed., Results: FN was detected less frequently in the tonsillar cores of RT patients (22%) than in those of patients without RT (30%) (p=0.44). FN detection frequencies ranged between 20% and 35% across the four groups. Betahaemolytic streptococci groups A/C/G (BHS) were detected significantly (p=0.007) more often in the RT group than in the halitosis/PSTS group., Conclusion: A possible role of FN in RT was not substantiated. Our results indicate that FN is likely to be part of the normal flora. The tonsillar surface and core flora carry considerable interpersonal diversity, but is very similar bilaterally in each individual. Other factors seem to play a major role in the development of the represented tonsillar diseases., Funding: Not relevant., Trial Registration: The study was approved by The Research Ethics Committee of Aarhus County (no. 20050034).
- Published
- 2011
395. Home management of oral anticoagulation via telemedicine versus conventional hospital-based treatment.
- Author
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Christensen H, Lauterlein JJ, Sørensen PD, Petersen ER, Madsen JS, and Brandslund I
- Subjects
- Adult, Aged, Aged, 80 and over, Drug Monitoring instrumentation, Female, Humans, International Normalized Ratio, Male, Middle Aged, Patient Education as Topic, Telemedicine instrumentation, User-Computer Interface, Young Adult, Anticoagulants blood, Drug Monitoring methods, Microcomputers, Telemedicine methods
- Abstract
Background and Objective: We have developed an expert computer system for the control of oral anticoagulation therapy, accessible by the patients via their own computer. To investigate if the weekly measurement and dosing of international normalized ratio (INR) at home using the online Internet-based system was superior to conventional treatment, we performed a randomized, controlled trial., Patients and Methods: All 669 patients in our anticoagulation clinic were asked to participate in the trial, providing that they had Internet access and could use the CoaguChek XS system. A total of 140 patients were included and randomized to (A) once weekly measurement and report online, (B) twice weekly measurement and report online, and (C) continued conventional treatment with INR measurement in the lab every 4 weeks and dose adjustment by letter., Results: Group A had 79.7% (95% CI 79.0-80.3) of time in therapeutic range (TTR), group B 80.2% (95% CI 79.4-80.9) of TTR, and group C 72.7% (95% CI 71.9-73.4) TTR. Groups A and B perform statistically significantly better than the conventional group C, with a difference of TTR of 7% points (p < 2.2 × 10(-16)), whereas no difference was seen between A and B., Conclusion: Home measurement of INR and the reporting and dosing of results online once a week increase TTR from 72% to 79% as compared to conventional computer-assisted monitoring in an anticoagulation clinic.
- Published
- 2011
- Full Text
- View/download PDF
396. The influence of statin treatment on the inflammatory biomarkers YKL-40 and HsCRP in patients with stable coronary artery disease.
- Author
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Mygind ND, Harutyunyan MJ, Mathiasen AB, Ripa RS, Thune JJ, Gøtze JP, Johansen JS, and Kastrup J
- Subjects
- Adipokines, Aged, Chitinase-3-Like Protein 1, Cholesterol blood, Female, Humans, Male, Middle Aged, Biomarkers blood, C-Reactive Protein immunology, Coronary Artery Disease blood, Coronary Artery Disease drug therapy, Coronary Artery Disease immunology, Glycoproteins blood, Glycoproteins immunology, Hydroxymethylglutaryl-CoA Reductase Inhibitors therapeutic use, Inflammation blood, Inflammation immunology, Lectins blood, Lectins immunology
- Abstract
Objective: The inflammatory biomarker YKL-40 is elevated and associated with mortality in patients with stable coronary artery disease (CAD). The aim was to investigate the influence of statin treatment and lipid status on serum YKL-40 and Hs-CRP in patients with stable CAD., Design: Serum YKL-40, HsCRP, total cholesterol, HDL-c, LDL-c and triglycerides levels were measured in 404 statin treated and in 404 matched non-statin treated patients with stable CAD., Results: YKL-40 was significantly higher in non-statin treated 110 µg/l (median) compared with 65 µg/l in statin treated (p < 0.001). HsCRP was 3.3 mg/l in non-statin treated compared with 2.1 mg/l in statin treated (p < 0.001). YKL-40 was not related to cholesterol levels for either statin or non-statin treated patients in the univariate analysis. In statin treated patients, HsCRP was related to a high level of total-cholesterol (p = 0.01) and a low level of HDL-c (p < 0.001)., Conclusions: HsCRP, but not YKL-40, is associated with the cholesterol levels in statin treated patients. This indicates that YKL-40 could be a superior prognostic biomarker in patients with stable CAD, since it is independent of changes in cholesterol levels in both statin and non-statin treated patients.
- Published
- 2011
- Full Text
- View/download PDF
397. Single-nucleotide variations in the genes encoding the mitochondrial Hsp60/Hsp10 chaperone system and their disease-causing potential.
- Author
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Bross P, Li Z, Hansen J, Hansen JJ, Nielsen MN, Corydon TJ, Georgopoulos C, Ang D, Lundemose JB, Niezen-Koning K, Eiberg H, Yang H, Kølvraa S, Bolund L, and Gregersen N
- Subjects
- Butyryl-CoA Dehydrogenase genetics, Child, Child, Preschool, Humans, Infant, Infant, Newborn, Malonates metabolism, Malonates urine, Promoter Regions, Genetic, Sudden Infant Death genetics, Chaperonin 10 genetics, Chaperonin 60 genetics, Genetic Predisposition to Disease, Mitochondrial Proteins genetics, Polymorphism, Single Nucleotide
- Abstract
Molecular chaperones assist protein folding, and variations in their encoding genes may be disease-causing in themselves or influence the phenotypic expression of disease-associated or susceptibility-conferring variations in many different genes. We have screened three candidate patient groups for variations in the HSPD1 and HSPE1 genes encoding the mitochondrial Hsp60/Hsp10 chaperone complex: two patients with multiple mitochondrial enzyme deficiency, 61 sudden infant death syndrome cases (MIM: #272120), and 60 patients presenting with ethylmalonic aciduria carrying non-synonymous susceptibility variations in the ACADS gene (MIM: *606885 and #201470). Besides previously reported variations we detected six novel variations: two in the bidirectional promoter region, and one synonymous and three non-synonymous variations in the HSPD1 coding region. One of the non-synonymous variations was polymorphic in patient and control samples, and the rare variations were each only found in single patients and absent in 100 control chromosomes. Functional investigation of the effects of the variations in the promoter region and the non-synonymous variations in the coding region indicated that none of them had a significant impact. Taken together, our data argue against the notion that the chaperonin genes play a major role in the investigated diseases. However, the described variations may represent genetic modifiers with subtle effects.
- Published
- 2007
- Full Text
- View/download PDF
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