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Siciliani D, Kortner TM, Berge GM, Hansen AK, Krogdahl Å. Effects of dietary lipid level and environmental temperature on lipid metabolism in the intestine and liver, and choline requirement in Atlantic salmon ( Salmo salar L) parr. J Nutr Sci 2023; 12:e61. [PMID: 37252685 PMCID: PMC10214143 DOI: 10.1017/jns.2023.45] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 05/18/2023] [Accepted: 05/02/2023] [Indexed: 05/31/2023] Open
Abstract
Choline was recently established as an essential nutrient for Atlantic salmon at all life stages. Choline deficiency is manifested as an excessive accumulation of dietary fat within the intestinal enterocytes, a condition known as steatosis. Most of today's plant-based salmon feeds will be choline-deficient unless choline is supplemented. Choline's role in lipid transport suggests that choline requirement may depend on factors such as dietary lipid level and environmental temperature. The present study was therefore conducted to investigate whether lipid level and water temperature can affect steatosis symptoms, and thereby choline requirement in Atlantic salmon. Four choline-deficient plant-based diets were formulated differing in lipid level of 16, 20, 25 and 28 % and fed to salmon of 25 g initial weight in duplicate tanks per diet at two different environmental temperatures: 8 and 15 °C. After 8 weeks of feeding, samples of blood, tissue and gut content from six fish per tank were collected, for analyses of histomorphological, biochemical and molecular biomarkers of steatosis and choline requirement. Increasing lipid level did not affect growth rate but increased relative weight and lipid content of the pyloric caeca and histological symptoms of intestinal steatosis and decreased fish yield. Elevation of the water temperature from 8 to 15 °C, increased growth rate, relative weight of the pyloric caeca, and the histological symptoms of steatosis seemed to become more severe. We conclude that dietary lipid level, as well as environmental temperature, affect choline requirement to a magnitude of importance for fish biology and health, and for fish yield.
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Affiliation(s)
- Daphne Siciliani
- Department of Paraclinical Sciences, Norwegian University of Life Sciences, Ås, Norway
| | - Trond M. Kortner
- Department of Paraclinical Sciences, Norwegian University of Life Sciences, Ås, Norway
| | | | | | - Åshild Krogdahl
- Department of Paraclinical Sciences, Norwegian University of Life Sciences, Ås, Norway
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Vøls KK, Kjelgaard-Hansen M, Ley CD, Hansen AK, Petersen M. In vivo fluorescence molecular tomography of induced haemarthrosis in haemophilic mice: link between bleeding characteristics and development of bone pathology. BMC Musculoskelet Disord 2020; 21:241. [PMID: 32290832 PMCID: PMC7158129 DOI: 10.1186/s12891-020-03267-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 04/03/2020] [Indexed: 12/17/2022] Open
Abstract
Background Haemophilic arthropathy is a chronic and debilitating joint disease caused by recurrent spontaneous joint bleeds in patients with haemophilia. Understanding how characteristics of individual joint bleeds relate to the subsequent development of arthropathy could improve management and prevention of this joint disease. Here, we aimed to explore relations between joint bleed characteristics and development of bone pathology in a mouse model of haemophilic arthropathy by using novel in vivo imaging methodology. Methods We characterised induced knee bleeds in a murine model of haemophilic arthropathy by quantitative in vivo fluorescence molecular tomography (FMT) and by measurements of changes in the diameter of the injured knee. Wild-type mice and non-injured haemophilic mice acted as controls. Development of arthropathy was characterised by post mortem evaluation of bone pathology by micro-CT 14 days after bleed-induction. In an in vitro study, we assessed the effect of blood on the quantification of fluorescent signal with FMT. Results In most injured haemophilic mice, we observed significant loss of trabecular bone, and half of the mice developed pathological bone remodelling. Development of pathological bone remodelling was associated with significantly increased fluorescent signal and diameter of the injured knee just 1 day after induction of the bleed. Further, a correlation between the fluorescent signal 1 day after induction of the bleed and loss of trabecular bone reached borderline significance. In the in vitro study, we found that high concentrations of blood significantly decreased the fluorescent signal. Conclusion Our results add novel insights on the pathogenesis of haemophilic arthropathy and underline the importance of the acute phase of joint bleeds for the subsequent development of arthropathy.
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Affiliation(s)
- K K Vøls
- Global Drug Discovery, Novo Nordisk A/S, Novo Nordisk Park 1, 2760, Maaloev, Denmark. .,Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg, Denmark.
| | - M Kjelgaard-Hansen
- Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - C D Ley
- Global Drug Discovery, Novo Nordisk A/S, Novo Nordisk Park 1, 2760, Maaloev, Denmark
| | - A K Hansen
- Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - M Petersen
- Global Drug Discovery, Novo Nordisk A/S, Novo Nordisk Park 1, 2760, Maaloev, Denmark
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Borgen TT, Bjørnerem Å, Solberg LB, Andreasen C, Brunborg C, Stenbro MB, Hübschle LM, Figved W, Apalset EM, Gjertsen JE, Basso T, Lund I, Hansen AK, Stutzer JM, Dahl C, Nordsletten L, Frihagen F, Eriksen EF. Determinants of trabecular bone score and prevalent vertebral fractures in women with fragility fractures: a cross-sectional sub-study of NoFRACT. Osteoporos Int 2020; 31:505-514. [PMID: 31754755 PMCID: PMC7075860 DOI: 10.1007/s00198-019-05215-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 10/28/2019] [Indexed: 12/15/2022]
Abstract
UNLABELLED Determinants of trabecular bone score (TBS) and vertebral fractures assessed semiquantitatively (SQ1-SQ3) were studied in 496 women with fragility fractures. TBS was associated with age, parental hip fracture, alcohol intake and BMD, not SQ1-SQ3 fractures. SQ1-SQ3 fractures were associated with age, prior fractures, and lumbar spine BMD, but not TBS. INTRODUCTION Trabecular bone score (TBS) and vertebral fractures assessed by semiquantitative method (SQ1-SQ3) seem to reflect different aspects of bone strength. We therefore sought to explore the determinants of and the associations between TBS and SQ1-SQ3 fractures. METHODS This cross-sectional sub-study of the Norwegian Capture the Fracture Initiative included 496 women aged ≥ 50 years with fragility fractures. All responded to a questionnaire about risk factors for fracture, had bone mineral density (BMD) of femoral neck and/or lumbar spine assessed, TBS calculated, and 423 had SQ1-SQ3 fracture assessed. RESULTS Mean (SD) age was 65.6 years (8.6), mean TBS 1.27 (0.10), and 33.3% exhibited SQ1-SQ3 fractures. In multiple variable analysis, higher age (βper SD = - 0.26, 95% CI: - 0.36,- 0.15), parental hip fracture (β = - 0.29, 95% CI: - 0.54,- 0.05), and daily alcohol intake (β = - 0.43, 95% CI - 0.79, - 0.08) were associated with lower TBS. Higher BMD of femoral neck (βper SD = 0.34, 95% CI 0.25-0.43) and lumbar spine (βper SD = 0.40, 95% CI 0.31-0.48) were associated with higher TBS. In multivariable logistic regression analyses, age (ORper SD = 1.94, 95% CI 1.51-2.46) and prior fragility fractures (OR = 1.71, 95% CI 1.09-2.71) were positively associated with SQ1-SQ3 fractures, while lumbar spine BMD (ORper SD = 0.75 95% CI 0.60-0.95) was negatively associated with SQ1-SQ3 fractures. No association between TBS and SQ1-SQ3 fractures was found. CONCLUSION Since TBS and SQ1-SQ3 fractures were not associated, they may act as independent risk factors, justifying the use of both in post-fracture risk assessment.
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Affiliation(s)
- T T Borgen
- Department of Rheumatology, Vestre Viken Hospital Trust, Drammen Hospital, Box 800, 3004, Drammen, Norway.
- Department of Clinical Medicine, University of Oslo, Oslo, Norway.
| | - Å Bjørnerem
- Department of Clinical Medicine, UiT - The Arctic University of Norway, Tromsø, Norway
- Department of Obstetrics and Gynecology, University Hospital of North Norway, Tromsø, Norway
| | - L B Solberg
- Division of Orthopedic Surgery, Oslo University Hospital, Oslo, Norway
| | - C Andreasen
- Department of Clinical Medicine, UiT - The Arctic University of Norway, Tromsø, Norway
- Department of Orthopedic Surgery, University Hospital of North Norway, Tromsø, Norway
| | - C Brunborg
- Oslo Centre for Biostatistics and Epidemiology, Research Support Services, Oslo University Hospital, Oslo, Norway
| | - M-B Stenbro
- Department of Rheumatology, Vestre Viken Hospital Trust, Drammen Hospital, Box 800, 3004, Drammen, Norway
| | - L M Hübschle
- Department of Orthopedic Surgery, Vestre Viken Hospital Trust, Drammen Hospital, Drammen, Norway
| | - W Figved
- Department of Orthopedic Surgery, Vestre Viken Hospital Trust, Bærum Hospital, Bærum, Norway
| | - E M Apalset
- Bergen group of Epidemiology and Biomarkers in Rheumatic Disease, Department of Rheumatology, Haukeland University Hospital, Bergen, Norway
- Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
| | - J-E Gjertsen
- Department of Orthopedic Surgery, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - T Basso
- Department of Orthopedic Surgery, St. Olavs University Hospital, Trondheim, Norway
| | - I Lund
- Division of Orthopedic Surgery, Oslo University Hospital, Oslo, Norway
| | - A K Hansen
- Department of Clinical Medicine, UiT - The Arctic University of Norway, Tromsø, Norway
- Department of Orthopedic Surgery, University Hospital of North Norway, Tromsø, Norway
| | - J-M Stutzer
- Department of Orthopedic Surgery, Møre and Romsdal Hospital Trust, Molde Hospital, Molde, Norway
| | - C Dahl
- Department of Community Medicine and Global health, Institute of Health and Society, University of Oslo, Oslo, Norway
| | - L Nordsletten
- Department of Clinical Medicine, University of Oslo, Oslo, Norway
- Division of Orthopedic Surgery, Oslo University Hospital, Oslo, Norway
| | - F Frihagen
- Division of Orthopedic Surgery, Oslo University Hospital, Oslo, Norway
| | - E F Eriksen
- Department of Clinical Medicine, University of Oslo, Oslo, Norway
- Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, Oslo, Norway
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Lindenberg F, Krych L, Kot W, Fielden J, Frøkiær H, van Galen G, Nielsen DS, Hansen AK. Development of the equine gut microbiota. Sci Rep 2019; 9:14427. [PMID: 31594971 PMCID: PMC6783416 DOI: 10.1038/s41598-019-50563-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 09/09/2019] [Indexed: 02/06/2023] Open
Abstract
Shortly after birth the mammalian gut is colonized, by a transient microbiota, highly susceptible to environment and diet, that eventually stabilizes and becomes the resident gut microbiota. In a window of opportunity during the colonization, oral tolerance is established towards resident bacteria. In this study, the development of the equine gut microbiota was investigated in ten foals from parturition until post weaning. We found great differences in the core species of the gut microbiota composition between time-matched samples on Day 7 and 20 post-partum. Between day 20 and Day 50 post-partum, we saw the gut microbiota became increasingly dominated by fiber fermenting species. After Day 50, no significant changes in species abundance were observed. Gene expression analysis of pro- and anti-inflammatory cytokines in the blood revealed no significant changes before and after weaning. In summary, relative stability of the gut microbiota was reached within 50 days post-partum and, weaning did not have a major impact on the microbial composition.
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Affiliation(s)
- F Lindenberg
- Brogaarden Aps, Copenhagen, Denmark. .,Faculty of Health and Medical Sciences, Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - L Krych
- Faculty of Sciences, Department of Food Science, University of Copenhagen, Copenhagen, Denmark
| | - W Kot
- Department of Environmental Sciences, Aarhus University, København, Denmark
| | | | - H Frøkiær
- Faculty of Health and Medical Sciences, Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
| | - G van Galen
- Faculty of Health and Medical Sciences, Department of Veterinary Clinical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - D S Nielsen
- Faculty of Sciences, Department of Food Science, University of Copenhagen, Copenhagen, Denmark
| | - A K Hansen
- Faculty of Health and Medical Sciences, Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
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Lindenberg F, Krych L, Fielden J, Kot W, Frøkiær H, van Galen G, Nielsen DS, Hansen AK. Expression of immune regulatory genes correlate with the abundance of specific Clostridiales and Verrucomicrobia species in the equine ileum and cecum. Sci Rep 2019; 9:12674. [PMID: 31481726 PMCID: PMC6722064 DOI: 10.1038/s41598-019-49081-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 08/16/2019] [Indexed: 01/06/2023] Open
Abstract
Billions of bacteria inhabit the gastrointestinal tract. Immune-microbial cross talk is responsible for immunological homeostasis, and symbiotic microbial species induce regulatory immunity, which helps to control the inflammation levels. In this study we aimed to identify species within the equine intestinal microbiota with the potential to induce regulatory immunity. These could be future targets for preventing or treating low-grade chronic inflammation occurring as a result of intestinal microbial changes and disruption of the homeostasis. 16S rRNA gene amplicon sequencing was performed on samples of intestinal microbial content from ileum, cecum, and colon of 24 healthy horses obtained from an abattoir. Expression of genes coding for IL-6, IL-10, IL-12, IL-17, 18 s, TNFα, TGFβ, and Foxp3 in the ileum and mesenteric lymph nodes was measured by qPCR. Intestinal microbiota composition was significantly different in the cecum and colon compared to the ileum, which contains large abundances of Proteobacteria. Especially members of the Clostridiales order correlated positively with the regulatory T-cell transcription factor Foxp3 and so did the phylum Verrucomicrobia. We conclude that Clostridiales and Verrucomicrobia have the potential to induce regulatory immunity and are possible targets for intestinal microbial interventions aiming at regulatory immunity improvement.
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Affiliation(s)
- F Lindenberg
- Brogaarden Aps, Lynge, Denmark. .,University of Copenhagen, Faculty of Health and Medical Sciences, Department of Veterinary and Animal Sciences, Copenhagen, Denmark.
| | - L Krych
- University of Copenhagen, Faculty of Sciences, Department of Food Science, Copenhagen, Denmark
| | | | - W Kot
- Department of Environmental Sciences, Aarhus University, Aarhus, Denmark
| | - H Frøkiær
- University of Copenhagen, Faculty of Health and Medical Sciences, Department of Veterinary and Animal Sciences, Copenhagen, Denmark
| | - G van Galen
- University of Copenhagen, Faculty of Health and Medical Sciences, Department of Veterinary Clinical Sciences, Copenhagen, Denmark
| | - D S Nielsen
- University of Copenhagen, Faculty of Sciences, Department of Food Science, Copenhagen, Denmark
| | - A K Hansen
- University of Copenhagen, Faculty of Health and Medical Sciences, Department of Veterinary and Animal Sciences, Copenhagen, Denmark
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Albrodt P, Jamal MT, Hansen AK, Jensen OB, Blume G, Paschke K, Crump P, Georges P, Lucas-Leclin G. Coherent combining of high brightness tapered amplifiers for efficient non-linear conversion. Opt Express 2019; 27:928-937. [PMID: 30696171 DOI: 10.1364/oe.27.000928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 12/17/2018] [Indexed: 06/09/2023]
Abstract
We report on a coherent beam combination of three high-brightness tapered amplifiers, which are seeded by a single-frequency laser at λ = 976 nm in a simple architecture with efficiently cooled emitters. The maximal combined power of 12.9 W is achieved at a combining efficiency of > 65%, which is limited by the amplifiers' intrinsic beam quality. The coherent combination cleans up the spatial profile, as the central lobe's power content increases by up to 86%. This high-brightness infrared beam is converted into the visible by second harmonic generation. This results in a high non-linear conversion efficiency of 4.5%/W and a maximum power over 2 W at 488 nm, which is limited by thermal effects in the periodically poled lithium niobate (PPLN).
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Tranberg B, Hellgren LI, Lykkesfeldt J, Hansen AK. High-fat feeding induces mobilization of vitamin C in obese prone rats. Res Vet Sci 2018; 119:167-169. [PMID: 29945036 DOI: 10.1016/j.rvsc.2018.06.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 06/06/2018] [Accepted: 06/10/2018] [Indexed: 11/30/2022]
Abstract
In obesity and dyslipidemia, hydrolysis of triacylglycerol (TAG) into non-esterified fatty acids (NEFAs) may contribute to insulin resistance, and production of oxygenated, bioactive polyunsaturated fatty acids may increase oxidative stress. Here we show that after six weeks of high-fat feeding of obese prone rats (Crl:OP(CD), vitamin C was increased both in liver (P < 0.01) and plasma (P < 0.001), while both TAG (P < 0.01) and NEFA (P < 0.001) were lower than in low-fat fed control rats. Hepatic vitamin C biosynthesis was similar between groups, indicating that a new steady state level was established with a higher vitamin C level adequate for supplying the systemic needs. Glucose and insulin sensitivity were unaffected at this stage. Eventually, the mobilization of vitamin C may be seen as a mechanism to protect the host against insulin resistance.
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Affiliation(s)
- B Tranberg
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - L I Hellgren
- Department of Systems Biology, Center for Biological Sequence Analysis, Technical University of Denmark, Lyngby, Denmark
| | - J Lykkesfeldt
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - A K Hansen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark.
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Jaeckel E, Basu A, Pieber TR, Hansen AK, Sach-Friedel S, Thomsen KMD, Basu R, Haahr H. Stärkere frühe postprandiale Suppression der endogenen Glucoseproduktion mit Faster aspart im Vergleich zu Insulin aspart. DIABETOL STOFFWECHS 2018. [DOI: 10.1055/s-0038-1641780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- E Jaeckel
- Medizinische Hochschule Hannover, Hannover, Germany
| | - A Basu
- Mayo Clinic, Rochester, United States
| | - TR Pieber
- Medizinische Universität, Graz, Austria
| | | | | | | | - R Basu
- Mayo Clinic, Rochester, United States
| | - H Haahr
- Novo Nordisk A/S, Søborg, Denmark
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Thairu MW, Skidmore IH, Bansal R, Nováková E, Hansen TE, Li-Byarlay H, Wickline SA, Hansen AK. Efficacy of RNA interference knockdown using aerosolized short interfering RNAs bound to nanoparticles in three diverse aphid species. Insect Mol Biol 2017; 26:356-368. [PMID: 28314050 DOI: 10.1111/imb.12301] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
RNA interference (RNAi) has emerged as a promising method for validating gene function; however, its utility in nonmodel insects has proven problematic, with delivery methods being one of the main obstacles. This study investigates a novel method of RNAi delivery in aphids, the aerosolization of short interfering RNA (siRNA)-nanoparticle complexes. By using nanoparticles as a siRNA carrier, the likelihood of cellular uptake is increased, when compared to methods previously used in insects. To determine the efficacy of this RNAi delivery system, siRNAs were aerosolized with and without nanoparticles in three aphid species: Acyrthosiphon pisum, Aphis glycines and Schizaphis graminum. The genes targeted for knockdown were carotene dehydrogenase (tor), which is important for pigmentation in Ac. pisum, and branched chain-amino acid transaminase (bcat), which is essential in the metabolism of branched-chain amino acids in all three aphid species. Overall, we observed modest gene knockdown of tor in Ac. pisum and moderate gene knockdown of bcat in Ap. glycines along with its associated phenotype. We also determined that the nanoparticle emulsion significantly increased the efficacy of gene knockdown. Overall, these results suggest that the aerosolized siRNA-nanoparticle delivery method is a promising new high-throughput and non-invasive RNAi delivery method in some aphid species.
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Affiliation(s)
- M W Thairu
- Department of Entomology, University of Illinois, Urbana-Champaign, IL, USA
| | - I H Skidmore
- Department of Entomology, University of Illinois, Urbana-Champaign, IL, USA
| | - R Bansal
- Department of Entomology, The Ohio State University, Wooster, OH, USA
| | - E Nováková
- Department of Entomology, University of Illinois, Urbana-Champaign, IL, USA
| | - T E Hansen
- Department of Entomology, University of Illinois, Urbana-Champaign, IL, USA
| | - H Li-Byarlay
- Department of Entomology, North Carolina State University, Raleigh, NC, USA
| | - S A Wickline
- School of Medicine, Washington University in St. Louis, MO, USA
| | - A K Hansen
- Department of Entomology, University of Illinois, Urbana-Champaign, IL, USA
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Hansen AK, Christensen M, Noordegraaf D, Heist P, Papastathopoulos E, Loyo-Maldonado V, Jensen OB, Skovgaard PMW. Efficient generation of 1.9 W yellow light by cascaded frequency doubling of a distributed Bragg reflector tapered diode. Appl Opt 2016; 55:9270-9274. [PMID: 27857320 DOI: 10.1364/ao.55.009270] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Watt-level yellow emitting lasers are interesting for medical applications, due to their high hemoglobin absorption, and for efficient detection of certain fluorophores. In this paper, we demonstrate a compact and robust diode-based laser system in the yellow spectral range. The system generates 1.9 W of single-frequency light at 562.4 nm by cascaded single-pass frequency doubling of the 1124.8 nm emission from a distributed Bragg reflector (DBR) tapered laser diode. The absence of a free-space cavity makes the system stable over a base-plate temperature range of 30 K. At the same time, the use of a laser diode enables the modulation of the pump wavelength by controlling the drive current. This is utilized to achieve a power modulation depth above 90% for the second harmonic light, with a rise time below 40 μs.
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Abstract
Renal epithelial proliferation has previously been found to be a common condition in a colony of Lewis × Brown Norway (BN) F2 hybrid rats. The aim of this study was to investigate the prevalence and clinical consequences of this condition in pure inbred BN and Lewis rats. Renal epithelial proliferation was found in 29 of 49 BN rats (59%) examined and in four of 50 Lewis rats (8%) examined. Serum creatinine and serum corticosterone was not influenced by the condition. Haematuria was more common in BN rats with (74%) than without renal papillary proliferation (35%, P < 0.05), but it may not be used to diagnose renal epithelial proliferation, as we found rats having renal epithelial proliferation without showing haematuria and rats showing haematuria without having renal epithelial proliferation. Haematuria was also common in Lewis rats (16-56% dependent of age and gender), in which renal epithelial proliferation were found in only 8%. Fluctuating asymmetry, which was used as a measure of developmental instability, was found to be increased in rats with renal epithelial proliferation ( P < 0.05). Haematuria was also found to be related to the degree of fluctuating asymmetry ( P < 0.01). Although the prevalence of renal epithelial proliferation is clearly higher in BN rats than in Lewis rats ( P < 0.01), and although in previous reports the condition was found in F2 BN × Lewis hybrids and not in F1 BN × Lewis hybrids it cannot clearly be defined as having been caused by a single Mendelian gene, as we found it in both inbred strains. Futhermore, we found that morphologically the proliferations could be placed on the papillary as well as the medullary wall of the renal pelvis, while previously it has only been described on the papillary wall.
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Affiliation(s)
- C Stub
- Division of Laboratory Animal Science and Welfare, Department of Pharmacology and Pathobiology, Royal Veterinary and Agricultural University, 3 Ridebanevej, DK-1870 Frederiksberg C, Denmark
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Sørensen KR, Roepstorff K, Wiinberg B, Hansen AK, Tranholm M, Nielsen LN, Kjelgaard-Hansen M. The F8(-/-) rat as a model of hemophilic arthropathy. J Thromb Haemost 2016; 14:1216-25. [PMID: 27060449 DOI: 10.1111/jth.13328] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Indexed: 01/20/2023]
Abstract
UNLABELLED Essentials Validating the F8 rat as a new intermediate-size animal model of hemophilic arthropathy. Factor VIII (FVIII) treated F8(-/-) rats suffered induced hemarthrosis analyzed by histopathology. F8 (-/-) animals develop hemophilic arthropathy upon hemarthrosis, preventable by FVIII treatment. The F8 (-/-) rat presents as a new pharmacologic model of hemophilic arthropathy. SUMMARY Background Translational animal models of hemophilia are valuable for determining the pathobiology of the disease and its co-morbidities (e.g. hemophilic arthropathy, HA). The biologic mechanisms behind the development of HA, a painful and debilitating condition, are not completely understood. We recently characterized a F8(-/-) rat, which could be a new preclinical model of HA. Objectives To establish the F8(-/-) rat as a model of HA by determining if the F8(-/-) rat develops HA resembling human HA after an induced joint bleed and whether a second joint bleed causes further disease progression. Methods Wild-type and F8(-/-) rats were treated with vehicle or recombinant human factor VIII (rhFVIII) prior to a needle-induced joint bleed. Joint swelling was measured prior to injury, the following 7 days and upon euthanasia. Histologic sections of the joint were stained, and athropathic changes identified and scored with regard to synovitis, bone remodelling, cartilage degradation and hemosiderin deposition. Results Vehicle-treated F8(-/-) rats experienced marked joint swelling and developed chronic degenerative joint changes (i.e. fibrosis of the subsynovial membrane, chondrocyte loss and excessive bone remodeling). Treatment with rhFVIII reduced or prevented swelling and degenerative joint changes, returning the F8(-/-) animals to a wild-type phenotype. Conclusion The hemophilic phenotype of the F8(-/-) rat resulted in a persistent hemarthrosis following an induced joint bleed. This caused development of HA resembling human HA, which was prevented by rhFVIII treatment, confirming the potential of the F8(-/-) rat as a model of HA.
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Affiliation(s)
- K R Sørensen
- Translational Haemophilia Pharmacology, Novo Nordisk A/S, Maaloev, Denmark
- Veterinary Disease Biology, University of Copenhagen, Copenhagen, Denmark
| | - K Roepstorff
- Histology and Bioimaging, Novo Nordisk A/S, Maaloev, Denmark
| | - B Wiinberg
- Translational Haemophilia Pharmacology, Novo Nordisk A/S, Maaloev, Denmark
| | - A K Hansen
- Veterinary Disease Biology, University of Copenhagen, Copenhagen, Denmark
| | - M Tranholm
- Haemophilia Pharmacology, Novo Nordisk A/S, Maaloev, Denmark
| | - L N Nielsen
- Translational Haemophilia Pharmacology, Novo Nordisk A/S, Maaloev, Denmark
- Veterinary Clinical and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
| | - M Kjelgaard-Hansen
- Translational Haemophilia Pharmacology, Novo Nordisk A/S, Maaloev, Denmark
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Islam A, Hansen AK, Mennan C, Martinez-Zubiaurre I. Mesenchymal stromal cells from human umbilical cords display poor chondrogenic potential in scaffold-free three dimensional cultures. Eur Cell Mater 2016; 31:407-24. [PMID: 27232667 DOI: 10.22203/ecm.v031a26] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Many researchers world over are currently investigating the suitability of stromal cells harvested from foetal tissues for allogeneic cell transplantation therapies or for tissue engineering purposes. In this study, we have investigated the chondrogenic potential of mesenchymal stromal cells (MSCs) isolated from whole sections of human umbilical cord or mixed cord (UCSCs-MC), and compared them with cells isolated from synovial membrane (SMSCs), Hoffa's fat pad (HFPSCs) and cartilage. All MSCs were positive for surface markers including CD73, CD90, CD105, CD44, CD146 and CD166, but negative for CD11b, CD19, CD34, CD45 and HLA-DR in addition to CD106 and CD271. Chondrogenic potential of all cell sources was studied using 3D pellet cultures incubated in the presence of different combinations of anabolic substances such as dexamethasone, IGF-1, TGF-β1, TGF-β3, BMP-2 and BMP-7. BMP-2 and dexamethasone in combination with TGF-β1 or TGF-β3 excelled at inducing chondrogenesis on SMSCs, HFPSCs and chondrocytes, as measured by glycosaminoglycans and collagen type II staining of pellets, quantitative glycosaminoglycan expression, quantitative PCR of cartilage signature genes and electron microscopy. In contrast, none of the tested growth factor combinations was sufficient to induce chondrogenesis on UCSCs-MC. Moreover, incubation of UCSCs-MC spheroids in the presence of cartilage pieces or synovial cells in co-cultures did not aid chondrogenic induction. In summary, we show that in comparison with MSCs harvested from adult joint tissues, UCSCs-MC display poor chondrogenic abilities. This observation should alert researchers at the time of considering UCSCs-MC as cartilage forming cells in tissue engineering or repair strategies.
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Affiliation(s)
- A Islam
- Institute of Clinical Medicine, University of Tromsø, Tromsø, 9037,
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Hansen AK, Tawfieq M, Jensen OB, Andersen PE, Sumpf B, Erbert G, Petersen PM. Concept for power scaling second harmonic generation using a cascade of nonlinear crystals. Opt Express 2015; 23:15921-15934. [PMID: 26193569 DOI: 10.1364/oe.23.015921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Within the field of high-power second harmonic generation (SHG), power scaling is often hindered by adverse crystal effects such as thermal dephasing arising from the second harmonic (SH) light, which imposes limits on the power that can be generated in many crystals. Here we demonstrate a concept for efficient power scaling of single-pass SHG beyond such limits using a cascade of nonlinear crystals, in which the first crystal is chosen for high nonlinear efficiency and the subsequent crystal(s) are chosen for power handling ability. Using this highly efficient single-pass concept, we generate 3.7 W of continuous-wave diffraction-limited (M(2)=1.25) light at 532 nm from 9.5 W of non-diffraction-limited (M(2)=7.7) light from a tapered laser diode, while avoiding significant thermal effects. Besides constituting the highest SH power yet achieved using a laser diode, this demonstrates that the concept successfully combines the high efficiency of the first stage with the good power handling properties of the subsequent stages. The concept is generally applicable and can be expanded with more stages to obtain even higher efficiency, and extends also to other combinations of nonlinear media suitable for other wavelengths.
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Abstract
Gut microbiota regulated imbalances in the host's immune profile seem to be an important factor in the etiology of type 1 diabetes (T1D), and identifying bacterial markers for T1D may therefore be useful in diagnosis and prevention of T1D. The aim of the present study was to investigate the link between the early gut microbiota and immune parameters of non-obese diabetic (NOD) mice in order to select alleged bacterial markers of T1D. Gut microbial composition in feces was analyzed with 454/FLX Titanium (Roche) pyro-sequencing and correlated with diabetes onset age and immune cell populations measured in diabetic and non-diabetic mice at 30 weeks of age. The early gut microbiota composition was found to be different between NOD mice that later in life were classified as diabetic or non-diabetic. Those differences were further associated with changes in FoxP3(+) regulatory T cells, CD11b(+) dendritic cells, and IFN-γ production. The model proposed in this work suggests that operational taxonomic units classified to S24-7, Prevotella, and an unknown Bacteriodales (all Bacteroidetes) act in favor of diabetes protection whereas members of Lachnospiraceae, Ruminococcus, and Oscillospira (all Firmicutes) promote pathogenesis.
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Key Words
- CD, cluster of differentiation
- DC, dendritic cell
- FoxP3, forkhead box
- IFN, interferon
- IFN-γ
- MLN, mesenteric lymph node
- NKT, natural killer T cell
- NOD mice
- PCA, principal component analysis
- PCoA, principal coordinate analysis
- PLN, pancreatic lymph node
- Treg, regulatory T cell
- Type 1 diabetes
- gut microbiota
- regulatory immunity
- siLP, small intestinal lamina propria
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Affiliation(s)
- Ł Krych
- Department of Food Science; Faculty of Science; University of Copenhagen; Copenhagen, Denmark,Correspondence to: Ł Krych;
| | - DS Nielsen
- Department of Food Science; Faculty of Science; University of Copenhagen; Copenhagen, Denmark
| | - AK Hansen
- Department of Veterinary Disease Biology; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen, Denmark
| | - CHF Hansen
- Department of Veterinary Disease Biology; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen, Denmark
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Pyndt Jørgensen B, Krych L, Pedersen TB, Plath N, Redrobe JP, Hansen AK, Nielsen DS, Pedersen CS, Larsen C, Sørensen DB. Investigating the long-term effect of subchronic phencyclidine-treatment on novel object recognition and the association between the gut microbiota and behavior in the animal model of schizophrenia. Physiol Behav 2014; 141:32-9. [PMID: 25545766 DOI: 10.1016/j.physbeh.2014.12.042] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 12/22/2014] [Accepted: 12/24/2014] [Indexed: 12/26/2022]
Abstract
Subchronic phencyclidine (subPCP) treatment induces schizophrenic-like behavior in rodents, including cognitive deficits and increased locomotor sensitivity towards acute administration of PCP. Evidence is accumulating that the gut microbiota (GM) influences behavior through modulation of the microbiota-gut-brain axis, and hence, part of the variation within this animal model may derive from variation in the GM. The aims of this study was to investigate first, the duration of subPCP-induced cognitive impairment in the novel object recognition test, and second, the possible effect of subchronic PCP-treatment on the GM, and the association between the GM and the behavioral parameters. The association was further investigated by antibiotic reduction of the GM. Male Lister Hooded rats were dosed twice daily i.p. with either 5mg/kg PCP or sterile isotonic saline for seven days followed by a seven-day washout period. Rats were tested in the novel object recognition and the locomotor activity assays immediately after, three weeks after, or six weeks after washout, and the fecal GM was analyzed by high throughput sequencing. Antibiotic- and control-treated rats were tested in the same manner following washout. In conclusion, subPCP-treatment impaired novel object recognition up to three weeks after washout, whereas locomotor sensitivity was increased for at least six weeks after washout. Differences in the core gut microbiome immediately after washout suggested subPCP treatment to alter the GM. GM profiles correlated to memory performance. Administration of ampicillin abolished the subPCP-induced memory deficit. It thus seems reasonable to speculate that the GM influences memory performance, contributing to variation within the model.
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Affiliation(s)
- B Pyndt Jørgensen
- Section of Experimental Animal Models, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Thorvaldsensvej 57, 1871 Frederiksberg C., Denmark.
| | - L Krych
- Department of Food Science, Faculty of Science, University of Copenhagen, Denmark
| | - T B Pedersen
- Nonclinical Safety Research, H. Lundbeck A/S, Valby, Denmark
| | - N Plath
- Synaptic Transmission, H. Lundbeck A/S, Valby, Denmark
| | - J P Redrobe
- Synaptic Transmission, H. Lundbeck A/S, Valby, Denmark
| | - A K Hansen
- Section of Experimental Animal Models, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Thorvaldsensvej 57, 1871 Frederiksberg C., Denmark
| | - D S Nielsen
- Department of Food Science, Faculty of Science, University of Copenhagen, Denmark
| | - C S Pedersen
- Synaptic Transmission, H. Lundbeck A/S, Valby, Denmark
| | - C Larsen
- Section of Experimental Animal Models, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Thorvaldsensvej 57, 1871 Frederiksberg C., Denmark
| | - D B Sørensen
- Section of Experimental Animal Models, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Thorvaldsensvej 57, 1871 Frederiksberg C., Denmark
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Ellekilde M, Krych L, Hansen CHF, Hufeldt MR, Dahl K, Hansen LH, Sørensen SJ, Vogensen FK, Nielsen DS, Hansen AK. Characterization of the gut microbiota in leptin deficient obese mice - Correlation to inflammatory and diabetic parameters. Res Vet Sci 2014; 96:241-50. [PMID: 24556473 DOI: 10.1016/j.rvsc.2014.01.007] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 01/08/2014] [Accepted: 01/26/2014] [Indexed: 02/07/2023]
Abstract
Gut microbiota have been implicated as a relevant factor in the development of type 2 diabetes mellitus (T2DM), and its diversity might be a cause of variation in animal models of T2DM. In this study, we aimed to characterise the gut microbiota of a T2DM mouse model with a long term vision of being able to target the gut microbiota to reduce the number of animals used in experiments. Male B6.V-Lep(ob)/J mice were characterized according to a number of characteristics related to T2DM, inflammation and gut microbiota. All findings were thereafter correlated to one another in a linear regression model. The total gut microbiota profile correlated to glycated haemoglobin, and high proportions of Prevotellaceae and Lachnospiraceae correlated to impaired or improved glucose intolerance, respectively. In addition, Akkermansia muciniphila disappeared with age as glucose intolerance worsened. A high proportion of regulatory T cells correlated to the gut microbiota and improved glucose tolerance. Furthermore, high levels of IL-10, IL-12 and TNF-α correlated to impaired glucose tolerance, blood glucose or glycated haemoglobin. The findings indicate that gut microbiota may contribute to variation in various disease read-outs in the B6.V-Lep(ob)/J model and considering them in both quality assurance and data evaluation for the B6.V-Lep(ob)/J model may have a reducing impact on the inter-individual variation.
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Affiliation(s)
- M Ellekilde
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Grønnegårdsvej 18, DK-1870 Frederiksberg C, Denmark.
| | - L Krych
- Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 30, DK-1958 Frederiksberg, Denmark
| | - C H F Hansen
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Grønnegårdsvej 18, DK-1870 Frederiksberg C, Denmark
| | - M R Hufeldt
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Grønnegårdsvej 18, DK-1870 Frederiksberg C, Denmark; Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 30, DK-1958 Frederiksberg, Denmark; Centre for Applied Laboratory Animal Research, Scanbur A/S, Silovej 16-18, DK-2690 Karlslunde, Denmark
| | - K Dahl
- Novo Nordisk, Department of Diabetes and Obesity Pharmacology, Novo Nordisk Park, DK-2760 Måløv, Denmark
| | - L H Hansen
- Department of Biology, Faculty of Science, University of Copenhagen, 1307 Copenhagen K, Denmark
| | - S J Sørensen
- Department of Biology, Faculty of Science, University of Copenhagen, 1307 Copenhagen K, Denmark
| | - F K Vogensen
- Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 30, DK-1958 Frederiksberg, Denmark
| | - D S Nielsen
- Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 30, DK-1958 Frederiksberg, Denmark
| | - A K Hansen
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Grønnegårdsvej 18, DK-1870 Frederiksberg C, Denmark
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Gu M, Kortner TM, Penn M, Hansen AK, Krogdahl Å. Effects of dietary plant meal and soya-saponin supplementation on intestinal and hepatic lipid droplet accumulation and lipoprotein and sterol metabolism in Atlantic salmon (Salmo salar L.). Br J Nutr 2014; 111:432-44. [PMID: 24507758 DOI: 10.1017/s0007114513002717] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Altered lipid metabolism has been shown in fish fed plant protein sources. The present study aimed to gain further insights into how intestinal and hepatic lipid absorption and metabolism are modulated by plant meal (PM) and soya-saponin (SA) inclusion in salmon feed. Post-smolt Atlantic salmon were fed for 10 weeks one of four diets based on fishmeal or PM, with or without 10 g/kg SA. PM inclusion resulted in decreased growth performance, excessive lipid droplet accumulation in the pyloric caeca and liver, and reduced plasma cholesterol levels. Intestinal and hepatic gene expression profiling revealed an up-regulation of the expression of genes involved in lipid absorption and lipoprotein (LP) synthesis (apo, fatty acid transporters, microsomal TAG transfer protein, acyl-CoA cholesterol acyltransferase, choline kinase and choline-phosphate cytidylyltransferase A), cholesterol synthesis (3-hydroxy-3-methylglutaryl-CoA reductase) and associated transcription factors (sterol regulatory element-binding protein 2 and PPARγ). SA inclusion resulted in reduced body pools of cholesterol and bile salts. The hepatic gene expression of the rate-limiting enzyme in bile acid biosynthesis (cytochrome P450 7A1 (cyp7a1)) as well as the transcription factor liver X receptor and the bile acid transporter abcb11 (ATP-binding cassette B11) was down-regulated by SA inclusion. A significant interaction was observed between PM inclusion and SA inclusion for plasma cholesterol levels. In conclusion, gene expression profiling suggested that the capacity for LP assembly and cholesterol synthesis was up-regulated by PM exposure, probably as a compensatory mechanism for excessive lipid droplet accumulation and reduced plasma cholesterol levels. SA inclusion had hypocholesterolaemic effects on Atlantic salmon, accompanied by decreased bile salt metabolism.
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Affiliation(s)
- Min Gu
- Department of Basic Science and Aquatic Medicine, Norwegian School of Veterinary Science, Aquaculture Protein Centre (a CoE), PO Box 8146 Dep, NO-0033 Oslo, Norway
| | - Trond M Kortner
- Department of Basic Science and Aquatic Medicine, Norwegian School of Veterinary Science, Aquaculture Protein Centre (a CoE), PO Box 8146 Dep, NO-0033 Oslo, Norway
| | - Michael Penn
- Department of Basic Science and Aquatic Medicine, Norwegian School of Veterinary Science, Aquaculture Protein Centre (a CoE), PO Box 8146 Dep, NO-0033 Oslo, Norway
| | | | - Åshild Krogdahl
- Department of Basic Science and Aquatic Medicine, Norwegian School of Veterinary Science, Aquaculture Protein Centre (a CoE), PO Box 8146 Dep, NO-0033 Oslo, Norway
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Versolato OO, Schwarz M, Hansen AK, Gingell AD, Windberger A, Kłosowski L, Ullrich J, Jensen F, Crespo López-Urrutia JR, Drewsen M. Decay rate measurement of the first vibrationally excited state of MgH+ in a cryogenic Paul trap. Phys Rev Lett 2013; 111:053002. [PMID: 23952392 DOI: 10.1103/physrevlett.111.053002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Indexed: 06/02/2023]
Abstract
We present a method to measure the decay rate of the first excited vibrational state of polar molecular ions that are part of a Coulomb crystal in a cryogenic linear Paul trap. Specifically, we have monitored the decay of the |ν = 1, J = 1)(X) towards the |ν = 0, J = 0)(X) level in MgH+ by saturated laser excitation of the |ν = 0, J = 2)(X)-|ν = 1, J = 1)(X) transition followed by state selective resonance enhanced two-photon dissociation out of the |ν = 0, J=2)(X) level. The experimentally observed rate of 6.32(0.69) s(-1) is in excellent agreement with the theory value of 6.13(0.03) s(-1) (this Letter). The technique enables the determination of decay rates, and thus absorption strengths, with an accuracy at the few percent level.
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Affiliation(s)
- O O Versolato
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany.
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20
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Schwarz M, Versolato OO, Windberger A, Brunner FR, Ballance T, Eberle SN, Ullrich J, Schmidt PO, Hansen AK, Gingell AD, Drewsen M, López-Urrutia JRC. Cryogenic linear Paul trap for cold highly charged ion experiments. Rev Sci Instrum 2012; 83:083115. [PMID: 22938282 DOI: 10.1063/1.4742770] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Storage and cooling of highly charged ions require ultra-high vacuum levels obtainable by means of cryogenic methods. We have developed a linear Paul trap operating at 4 K capable of very long ion storage times of about 30 h. A conservative upper bound of the H(2) partial pressure of about 10(-15) mbar (at 4 K) is obtained from this. External ion injection is possible and optimized optical access for lasers is provided, while exposure to black body radiation is minimized. First results of its operation with atomic and molecular ions are presented. An all-solid state laser system at 313 nm has been set up to provide cold Be(+) ions for sympathetic cooling of highly charged ions.
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Affiliation(s)
- M Schwarz
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany.
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Hansen CHF, Krych L, Nielsen DS, Vogensen FK, Hansen LH, Sørensen SJ, Buschard K, Hansen AK. Early life treatment with vancomycin propagates Akkermansia muciniphila and reduces diabetes incidence in the NOD mouse. Diabetologia 2012; 55:2285-94. [PMID: 22572803 DOI: 10.1007/s00125-012-2564-7] [Citation(s) in RCA: 351] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 03/21/2012] [Indexed: 10/28/2022]
Abstract
AIMS/HYPOTHESIS Increasing evidence suggests that environmental factors changing the normal colonisation pattern in the gut strongly influence the risk of developing autoimmune diabetes. The aim of this study was to investigate, both during infancy and adulthood, whether treatment with vancomycin, a glycopeptide antibiotic specifically directed against Gram-positive bacteria, could influence immune homeostasis and the development of diabetic symptoms in the NOD mouse model for diabetes. METHODS Accordingly, one group of mice received vancomycin from birth until weaning (day 28), while another group received vancomycin from 8 weeks of age until onset of diabetes. Pyrosequencing of the gut microbiota and flow cytometry of intestinal immune cells was used to investigate the effect of vancomycin treatment. RESULTS At the end of the study, the cumulative diabetes incidence was found to be significantly lower for the neonatally treated group compared with the untreated group, whereas the insulitis score and blood glucose levels were significantly lower for the mice treated as adults compared with the other groups. Mucosal inflammation was investigated by intracellular cytokine staining of the small intestinal lymphocytes, which displayed an increase in cluster of differentiation (CD)4(+) T cells producing pro-inflammatory cytokines in the neonatally treated mice. Furthermore, bacteriological examination of the gut microbiota composition by pyrosequencing revealed that vancomycin depleted many major genera of Gram-positive and Gram-negative microbes while, interestingly, one single species, Akkermansia muciniphila, became dominant. CONCLUSIONS/INTERPRETATION The early postnatal period is a critical time for microbial protection from type 1 diabetes and it is suggested that the mucolytic bacterium A. muciniphila plays a protective role in autoimmune diabetes development, particularly during infancy.
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Affiliation(s)
- C H F Hansen
- Section of Biomedicine, Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 57, 1870, Frederiksberg C, Denmark.
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Abstract
The metabolic syndrome (MetS) is one of the most important challenges to public health and biomedical research. Animal models of MetS, such as leptin-deficient obese mice, obese spontaneously hypertensive rats, JCR: LA-cp rats and the Ossabaw and Göttingen minipigs, have contributed to our understanding of the pathophysiological basis and the development of novel therapies. For a complex disease syndrome, no animal model can be expected to serve all needs of research. Although each animal model has limitations and strengths, used together in a complementary fashion, they are essential for research on the MetS and for rapid progress in understanding the aetiology and pathogenesis towards a cure. The purpose of this review is to assess how current animal models contributed to our knowledge of the human MetS, and to systematically evaluate the strengths and weaknesses of the currently available 78 animal models from 11 species.
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Affiliation(s)
- O Varga
- Laboratory Animal Science group, Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal.
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Hansen AK, Galante M, McCarren D, Sears S, Scime EE. Simultaneous two-dimensional laser-induced-fluorescence measurements of argon ions. Rev Sci Instrum 2010; 81:10D701. [PMID: 21033894 DOI: 10.1063/1.3460630] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Recent laser upgrades on the Hot Helicon Experiment at West Virginia University have enabled multiplexed simultaneous measurements of the ion velocity distribution function at a single location, expanding our capabilities in laser-induced fluorescence diagnostics. The laser output is split into two beams, each modulated with an optical chopper and injected perpendicular and parallel to the magnetic field. Light from the crossing point of the beams is transported to a narrow-band photomultiplier tube filtered at the fluorescence wavelength and monitored by two lock-in amplifiers, each referenced to one of the two chopper frequencies.
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Affiliation(s)
- A K Hansen
- Department of Physics, West Virginia University, P.O. Box 6315, Morgantown, West Virginia 26506-6315, USA.
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Abstract
An increasing number of rodents are housed in individually ventilated cage (IVC) systems, as these seem to be very effective for the protection of animals against infections, as well as protecting the staff against allergens. For the IVC systems to be properly ventilated, a huge amount of air has to be blown into the cage, which may cause a draught at animal level inside the cage. The aim of the present study was to evaluate the preferences of mice for differing levels of air speeds and air changes inside the cage. It has been concluded that mice do react to draughts, whereas they do not seem to be affected by a high number of air changes delivered without draught, which underlines the importance of applying draught-free IVC systems for mice.
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Affiliation(s)
- T C Krohn
- Centre for Applied Laboratory Animal Research, Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen, 1870 Frederiksberg C, Denmark
| | - A K Hansen
- Centre for Applied Laboratory Animal Research, Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen, 1870 Frederiksberg C, Denmark
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Hufeldt MR, Nielsen DS, Vogensen FK, Midtvedt T, Hansen AK. Family relationship of female breeders reduce the systematic inter-individual variation in the gut microbiota of inbred laboratory mice. Lab Anim 2010; 44:283-9. [PMID: 20713427 DOI: 10.1258/la.2010.010058] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The gut microbiota (GM) may influence disease expression in several animal models for inflammatory diseases. It may therefore seem reasonable to pursue reduction in the number of animals used for individual studies by reducing the variation in the GM. Previous studies have shown that the composition of the GM is related to genetics to a certain extent. We hypothesized that the GM similarity in a group of mice born by mothers not being sisters would be lower than that in a group born by mothers being sisters. The lower similarity could lead to clustering of the GM of mice born by non-sisters according to their mothers, while such clustering would not be visible if the mothers were sisters. We used 16S rRNA gene (V3 region) polymerase chain reaction-derived amplicon profiling by denaturing gradient gel electrophoresis (DGGE) to study the GM composition in caecum samples of 33 eight-week-old C57BL/6Sca mice from a breeding set-up with dam breeders that were sisters, as well as caecum samples of 35 eight-week-old C57BL/6Sca mice from a breeding set-up with dam breeders that were not sisters. Principal component analysis revealed a significant difference between the litters from the breeding set-up with dam breeders that were not sisters, whereas no significant difference between the litters based on the breeding set-up with dam breeders that were sisters was observed. The results obtained indicate that the systematic variation in the GM of inbred mice can be reduced by increasing the family relatedness of the breeding pairs.
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Affiliation(s)
- M R Hufeldt
- Department of Veterinary Disease Biology, Faculty of Life Sciences, Centre for Applied Laboratory Animal Research, University of Copenhagen, 1870 Frederiksberg C, Denmark
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Hansen AK, Josefsen K, Pedersen C, Buschard K. Neonatal stimulation of beta-cells reduces the incidence and delays the onset of diabetes in a barrier-protected breeding colony of BB rats. Exp Clin Endocrinol 2009; 101:189-93. [PMID: 8223991 DOI: 10.1055/s-0029-1211230] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The off-spring in a barrier maintained colony of spontaneously type 1 diabetic BB/Wor/Mol-BB rats was treated with a daily injection of either saline, forskolin, arginine, glucose or both glucose and arginine for the first six days after birth. The incidence was reduced from 88% to 72% by the neonatal stimulation with arginine and glucose in combination, which also delayed the onset time from 76.0 +/- 2.2 days to 88.1 +/- 2.3 days. No such effect was observed after stimulation with either one of the compounds. Neonatal stimulation with forskolin also delayed the onset to 87.9 +/- 3.8 days, however without reducing the incidence. A higher incidence of diabetes was observed in the barrier-protected rats taking part in this study than in an earlier study using BB rats of the same origin, but kept under conventional conditions.
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Affiliation(s)
- A K Hansen
- Animal Department, Panum Institute, University of Copenhagen
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27
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Thon R, Vondeling H, Lassen J, Hansen AK, Ritskes-Hoitinga M. An interview study of phenotypic characterization of genetically-modified mice. Lab Anim 2009; 43:278-83. [PMID: 19237456 DOI: 10.1258/la.2008.0080058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
An interview study was carried out with the aim of clarifying the reasons for the limited use of phenotypic characterization of genetically-modified mice (GMM) and identifying issues hindering its implementation. A total of 15 users of GMM participated in semi-structured face-to-face interviews, which were audio-taped and transcribed. The results were extracted using content analysis by theme. The investigation confirmed that few animals were systematically phenotyped and an observational approach was found to be widespread. The primary interest of the interviewees was phenotyping for impaired animal welfare. The concept of phenotyping was widely understood and perceived as a scientific advantage. The comprehensiveness of the protocols and the resources required for phenotyping were seen as problematic. All participants addressed this issue, be it regarding lack of time, money or expertise. Also, among the negative statements were worries about the capability of the available protocols to produce the information needed by the individual scientist. Phenotyping was predicted to become much more widespread in the future and its success was expected to depend on the development of reliable, fast and inexpensive methods. The study identified different aims of phenotyping and the suitability of the published protocols for these purposes was discussed. The contradiction between the limited use of characterization and its advantages was also discussed and proposals for the improvement of future phenotyping strategies are formulated.
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Affiliation(s)
- R Thon
- Pixiegene A/S, Axelborg, Axeltorv 3, DK-1609 Copenhagen V, Denmark.
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Christensen SD, Mikkelsen LF, Fels JJ, Bodvarsdóttir TB, Hansen AK. Quality of plasma sampled by different methods for multiple blood sampling in mice. Lab Anim 2008; 43:65-71. [PMID: 19001062 DOI: 10.1258/la.2008.007075] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
For oral glucose tolerance test (OGTT) in mice, multiple blood samples need to be taken within a few hours from conscious mice. Today, a number of essential parameters may be analysed on very small amounts of plasma, thus reducing the number of animals to be used. It is, however, crucial to obtain high-quality plasma or serum in order to avoid increased data variation and thereby increased group sizes. The aim of this study was to find the most valid and reproducible method for withdrawal of blood samples when performing OGTT. Four methods, i.e. amputation of the tail tip, lateral tail incision, puncture of the tail tip and periorbital puncture, were selected for testing at 21 degrees C and 30 degrees C after a pilot study. For each method, four blood samples were drawn from C57BL/6 mice at 30 min intervals. The presence of clots was registered, haemolysis was monitored spectrophotometrically at 430 nm, and it was noted whether it was possible to achieve 30-50 microL blood. Furthermore, a small amount of extra blood was sampled before and after the four samplings for testing of whether the sampling induced a blood glucose change over the 90 min test period. All methods resulted in acceptable amounts of plasma. Clots were observed in a sparse number of samples with no significant differences between the methods. Periorbital puncture did not lead to any haemolysed samples at all, and lateral tail incision resulted in only a few haemolysed samples, while puncture or amputation of the tail tip induced haemolysis in a significant number of samples. All methods, except for puncture of the tail tip, influenced blood glucose. Periorbital puncture resulted in a dramatic increase in blood glucose of up to 3.5 mmol/L indicating that it is stressful. Although lateral tail incision also had some impact on blood glucose, it seems to be the method of choice for OGTT, as it is likely to produce a clot-free non-haemolysed sample, while periorbital sampling, although producing a high quality of sample, induces such a dramatic change in blood glucose that it should not be applied for OGTT in mice.
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Affiliation(s)
- S D Christensen
- Department of Veterinary Pathobiology, University of Copenhagen, Dyrlaegevej 88, DK-1870 Frederiksberg C, Denmark
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29
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Abstract
Implantable microchips provide a secure, permanent and unique identification of individual animals. When performing fetal intervention studies in experimental animal models easy and secure identification of fetuses is desirable, as having test and control groups within the same uterus reduces the total number of animals used in a study. The aims of this study were: (1) to establish a protocol to identify porcine fetuses in utero by microchip implantation and (2) to assess postnatally whether clinical or pathological reactions to the implant occurred. Two Danish Landrace/Danish Large White crossbred sows at day 100 of gestation were used. The sows were sedated with azaperone and induced with propofol intravenously. Anaesthesia was maintained with isoflurane and oxygen. Antibiotics were administered intramuscularly (i.m.) at induction and analgesia was given pre-, intra- and postoperatively. A laparotomy was performed and the uterus exteriorized. The rump of the first fetus was recognized through the uterine wall and the thigh muscle of the fetus was fixed between the thumb and the forefinger. The microchip was then implanted into the fetus at an angle of 45° i.m. in the lateral hindleg using an insertion device with a 12G needle. The same procedure was done in every fetus. The uterus was returned to the abdomen and the abdominal wall closed. The sows gave birth to 24 liveborn piglets and one stillborn. None of the liveborn piglets were limping at the time of birth and no visible cutaneous or palpable reactions on the hindlegs were observed. Following euthanasia, the microchip was easily localized and no macroscopic reactions at the implantation site were seen. None of the piglets had more than one microchip implanted. Histology showed a chronic mild foreign body granulomatous inflammatory response with peripheral eosinophils surrounding the microchip. No inflammation was evident in the adjacent muscles. It is concluded that transuterine identification of piglets two weeks before delivery is feasible using a microchip implant as an effective, easy and reliable method for identification of individuals after birth.
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Affiliation(s)
- M M Birck
- Division of Laboratory Animal Science and Welfare, Department of Veterinary Pathobiology, Faculty of Life Sciences
| | - T Iburg
- Section of Pathology, Department of Veterinary Pathobiology, Faculty of Life Sciences
| | - M Schmidt
- Veterinary Reproduction and Obstetrics, Department of Large Animals Sciences, Faculty of Life Sciences
| | - P T Sangild
- Department of Human Nutrition, Faculty of Life Sciences, University of Copenhagen, Denmark
| | - A K Hansen
- Division of Laboratory Animal Science and Welfare, Department of Veterinary Pathobiology, Faculty of Life Sciences
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Ejsing-Duun M, Josephsen J, Aasted B, Buschard K, Hansen AK. Dietary gluten reduces the number of intestinal regulatory T cells in mice. Scand J Immunol 2008; 67:553-9. [PMID: 18476878 DOI: 10.1111/j.1365-3083.2008.02104.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
It is well established that gluten-free diet reduces the incidence of type 1 diabetes mellitus (T1D) in non-obese diabetic (NOD) mice, though the mechanism is not known. However, regulatory T cells (Treg) are likely to play an important role. Also, it is known that dietary gluten induces an intestinal increase in the bacterium Lactococcus garvieae, but the importance of this phenomenon for T1D development is doubtful. Our hypothesis is that gluten is responsible for mediating its effect on T1D through the influence on Treg development independent of gluten-induced Lactococci. Four groups of female NOD and BALB/c mice of 3 week old were fed either a gluten-free diet or a standard diet. Lactococcus garvieae or saline water was administered per oral to one of each dietary group. Spleen and Peyer's patches were sampled from BALB/c mice for flow cytometric monitoring of IL-10 and Treg. NOD mice were diagnosed diabetic with blood glucose level >12 mmol/l. Dietary gluten significantly decreased the occurrence of Tregs by 10-15% (P < 0.05) in mice compared with those fed a standard diet. These results and the diabetes incidence were independent of the gluten-induced bacterial factor Lactococci. The prevalence of Treg was 5- to 10-fold more abundant in the Peyer's patches than in the spleen (P < 0.001). In conclusion, dietary gluten has a significant negative quantitative impact on the generation of Treg in mice, independent of gluten-induced Lactococcus garvieae, and Treg are far more abundant in Peyer's patches than in the spleen.
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Affiliation(s)
- M Ejsing-Duun
- Department of Veterinary Pathobiology, Faculty of Life Sciences, University of Copenhagen, Frederiksberg C, Denmark
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Abstract
PNMT (phenylethanolamine-N-methyl-transferase) is the enzyme that catalyzes the formation of epinephrine from norepinephrine. In transgenic mice over-expressing PNMT, observations revealed a very high level of aggression compared to their background strain, C57BL/6J. To evaluate the influence of PNMT on aggression and emotionality in this transgenic line, single-sex male and female groups were independently established that consisted of either four wild-type mice or four transgenic mice overexpressing PNMT. The members of each group were littermates. Mixed single-sex groups consisting of two transgenic mice and two wild-type mice were also established. Almost no fights were observed within the female groups. In males, the transgenic line showed a significantly higher level of fighting than controls (p=0.007) and mixed male groups (p=0.02). Housing mice from the transgenic line in mixed groups with wild-type mice seems to decrease the level of aggression in the transgenic line. In conclusion, this is the first study to demonstrate a clear, significant increase in aggression arising from PNMT overexpression. This suggests an important role for central epinephrine levels in aggressive behavior.
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Affiliation(s)
- D B Sørensen
- The Royal Veterinary and Agricultural University of Copenhagen, Division of Laboratory Animal Science and Welfare, Department of Veterinary Pathobiology, Frederiksberg, Denmark.
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Dahl K, Kirkeby S, d'Apice AFJ, Mathiassen S, Hansen AK. The bacterial flora of α-Gal knockout mice express the α-Gal epitope comparable to wild type mice. Transpl Immunol 2005; 14:9-16. [PMID: 15814276 DOI: 10.1016/j.trim.2004.11.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2004] [Revised: 11/05/2004] [Accepted: 11/16/2004] [Indexed: 11/19/2022]
Abstract
The human genome possesses pseudogenes for the enzyme alpha1,3 galactosyltransferase and hence, human cells and tissues do not express the Galalpha terminated trisaccharide structure Galalpha1-3Galbeta1-4GlcNAc, the so-called alpha-Gal epitope. Circulating antibodies specific for this carbohydrate epitope are, however, present in high amounts in humans. It has previously been hypothesized that the antibody production is induced by the presence of the alpha-Gal epitope in the cell walls of the enteric flora, especially Enterobacteriaceae spp. However, in mice, in which the epitope has been deleted by targeted mutation of the gal-transferase gene, alpha-Gal antibodies do not appear without prior immunization, although the mice through their growth probably have been exposed to a normal bacterial flora of e.g. Enterobacteriaceae spp. It is unknown whether there are different types of immune reactions to antigenic carbohydrate expressing bacteria and whether there are discrepancies in the enteric flora between these knockout mice and their wild type litter mates. In this study the enteric flora of alpha-Gal knockout and wild type mice was compared both in relation to the prevalence of different types of bacteria in the two groups of mice, as well as in relation to the expression of the epitope on the surface of Enterobacteriaceae spp. Our results showed that the enteric flora did not differ significantly between knockout and wild type mice and that it was comparable to the flora known to be present in the intestines of other mice. All Enterobacteriaceae spp. examined expressed the alpha-Gal epitope no matter whether they were isolated from knockout or wild type mice. It is, therefore, discussed whether it is more reasonable to assume that alpha-Gal antibodies in mammals that do not produce alpha1,3 galactosyltransferase such as in the knock mice and in humans are the result of another antigen stimulant than these common representatives of the enteric flora, that we isolated from the two types of mice. Possible candidates for a carrier in humans could be bacteria or viruses not isolated from barrier-bred mice.
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Affiliation(s)
- K Dahl
- Division of Laboratory Animal Science and Welfare, Department of Veterinary Pathobiology, Royal Veterinary and Agricultural University, Dyrlaegevej 35, DK-1870 Frederiksberg C, Denmark
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Mellau LSB, Jørgensen RJ, Bartlett PC, Enemark JMD, Hansen AK. Effect of anionic salt and highly fermentable carbohydrate supplementations on urine pH and on experimentally induced hypocalcaemia in cows. Acta Vet Scand 2005; 45:139-47. [PMID: 15663074 PMCID: PMC1820990 DOI: 10.1186/1751-0147-45-139] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The objective of this experiment was to determine the effect of dietary grain on calcium homeostasis. Six rumen-fistulated dairy cows with 3 or more previous lactations and no history of parturient paresis were randomly assigned to a sequence of diets in a crossover study with 4 periods of 10 days each. Dietary treatments were: A control ration consisting of wrap grass silage alone (1), the control ration supplemented with ammonium chloride and ammonium sulphate salt solution (2), control ration following a period with supplementation (3) and control ration supplemented with increasing amounts of barley from 4 to 10 kg/cow per day, expected to produce subclinical rumen acidosis (4). Daily intake of the diets was adjusted to 14 kg DM/cow per day. On day 11, the calcium-regulating mechanisms in cows were challenged until recumbency by a standardized intravenous EDTA infusion and cows were left to recover spontaneously. Anion supplementation and the feeding of highly fermentable carbohydrate lowered urine pH below 7.0 due to subclinical acidosis. During spontaneous recovery from EDTA induced hypocalcaemia, the cows more quickly regained a whole blood free calcium concentration of 1.00 mmol/L if they had most recently been supplemented with either anionic salts or with increasing amounts of barley, as compared to the basic ration. It is concluded that so-called slug-feeding or 'steaming up' with highly fermentable carbohydrates before parturition in milk fever susceptible cows enhanced calcium homeostasis similar to the effect seen in cows on anionic diets.
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Affiliation(s)
- L S B Mellau
- Cattle Production Medicine Research Group, Department of Large Animal Sciences, The Royal Veterinary and Agricultural University, Denmark.
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Jelsing J, Olsen AK, Cumming P, Gjedde A, Hansen AK, Arnfred S, Hemmingsen R, Pakkenberg B. A volumetric screening procedure for the Göttingen minipig brain. Exp Brain Res 2005; 162:428-35. [PMID: 15668795 DOI: 10.1007/s00221-004-2026-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2003] [Accepted: 06/14/2004] [Indexed: 10/25/2022]
Abstract
A screening procedure was developed to provide quantitative estimates of structural parameters, regional volumes and neuron number, in a neurotoxicologic study of the Göttingen minipig brain. The study material consisted of normal controls and brains collected from young minipigs which had been exposed in utero to the mitotic inhibitor methylazoxymethanol acetate (MAM). Based on stereological principles and systematic sampling techniques, volumetric data from pre-selected regions of the pig brain was obtained using Cavalieri's principles and point-counting. Secondarily, estimates of total hemispheric neocortical cell numbers were obtained from pre-selected groups to test the potential effect of MAM on neuron number. No significant differences were observed in volume of the pre-selected regions of MAM intoxicated pigs nor in estimates of total neocortical neuron number.
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Affiliation(s)
- J Jelsing
- Research Laboratory for Stereology and Neuroscience, University Hospital Copenhagen, Bispebjerg, Denmark.
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35
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Arnfred SM, Lind NM, Gjedde A, Hansen AK. Scalp recordings of mid-latency AEP and auditory gating in the Göttingen minipig: a new animal model in information processing research. Int J Psychophysiol 2004; 52:267-75. [PMID: 15094249 DOI: 10.1016/j.ijpsycho.2003.11.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2003] [Revised: 11/13/2003] [Accepted: 11/19/2003] [Indexed: 11/30/2022]
Abstract
Early central information processing, measured in humans by the gating of the middle latency auditory evoked potential (AEP) P50 and the effect of attention on AEP N100, is affected in schizophrenia. Exploring the possibility of using miniature pigs in longitudinal studies of chronic neuropsychiatric disorders, we present a method for recording seven channel surface middle latency AEP in the awake animal. The AEP and the AEP gating measured in a paired stimulus paradigm similar to the P50 gating paradigm used in humans, were recorded in six adult male minipigs in two sessions. The AEP had a stable N40/P60/N120/P200 configuration and in the gating paradigm the difference between stimulus one (S1) and two (S2) P60 and N120 amplitudes were significant. Mean AEP P60 gating ratio (S2/S1) at the posterior central electrode was 0.66 (std 0.29) range 0.21-1.08 and corresponding N120 was 0.60 (std 0.19) range 0.28-0.76. The method presented is feasible for scalp recordings of middle latency evoked potentials in the awake animal, but further studies of interval sensitivity and the effect of arousal manipulation are needed to assess the equivalence of the pig components to those of the human at similar latencies.
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Affiliation(s)
- S M Arnfred
- Department of Psychiatry, H:S Hvidovre Hospital, University Hospital of Copenhagen, Brøndbyøstervej 160, DK-2605 Brøndby, Denmark.
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Abstract
INTRODUCTION Clinical databases are increasingly being employed to evaluate the quality of treatments, including patients with peripheral vascular disease. Valid data is vital to the value of these analyses. OBJECTIVE To assess the validity of clinical data in a population-based national vascular registry. DESIGN Traditional reproducibility study was supplemented by refilling of data by an independent observer, thereby creating three data sets for comparison. MATERIALS AND METHODS Twenty prospectively recorded electronic forms from each department were selected randomly from the Danish National Vascular Registry. Data forms were refilled by the surgeons of the department concerned, and by an independent member of the board of the Danish National Vascular Registry. Refilling was performed blinded to the original forms. CONCLUSIONS A high degree of accuracy of clinical data can be achieved. An independent observer makes it possible to evaluate the classification of observer dependent parameters and explain differences in the reproducibility of data.
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Affiliation(s)
- J Laustsen
- Department of Cardiothoracic and Vascular Surgery T, Aarhus University Hospital, Skejby Sygehus, Denmark
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Jegstrup I, Thon R, Hansen AK, Hoitinga MR. Characterization of transgenic mice--a comparison of protocols for welfare evaluation and phenotype characterization of mice with a suggestion on a future certificate of instruction. Lab Anim 2003; 37:1-9. [PMID: 12626067 DOI: 10.1258/002367703762226647] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A thorough welfare evaluation performed as part of a general phenotype characterization for both transgenic and traditional mouse strains could not only contribute to the improvement of the welfare of laboratory animals, but could also be of benefit to scientists, laboratory veterinarians and the inspecting authorities. A literature review has been performed to identify and critically evaluate already existing protocols for phenotype and welfare characterization. There are several relevant schemes available, among others the SHIRPA method, the modified score sheet of Morton and Griffiths, the FRIMORFO phenotype characterization scheme and the behavioural phenotype schemes as described by Crawley. These protocols have been evaluated according to four goals: Their ability (1) to reveal any special needs or problems with a transgenic strain, (2) to cover the informational needs of the purchaser/user of the strain, (3) to refine the welfare of the transgenic animal model by identifying relevant humane endpoints, (4) to prevent the duplication of animal models that have already been developed. The protocols described are useful for characterizing the phenotype and judging welfare disturbances, however the total amount of information and the degree of detail varies considerably from one scheme to another. We present a proposal regarding the practical application of the various schemes that will secure proper treatment and the identification of humane endpoints. It is advocated that with every purchase of a particular strain, an instruction document should accompany the strain. This document needs to give detailed descriptions of the typical characteristics of the strain, as well as necessary actions concerning relevant treatment and humane endpoints. At the moment no such documents are required. The introduction of these types of documents will contribute to improvements in animal welfare as well as experimental results in laboratory animal experimentation.
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Affiliation(s)
- I Jegstrup
- Centre of Bioethics and Risk Assessment, Biomedical Laboratory, University of Southern Denmark, Winsloewparken 23, DK-5000 Odense C, Denmark.
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Naver B, Stub C, Møller M, Fenger K, Hansen AK, Hasholt L, Sørensen SA. Molecular and behavioral analysis of the r6/1 huntington′s disease transgenic mouse. Neuroscience 2003; 122:1049-57. [PMID: 14643771 DOI: 10.1016/j.neuroscience.2003.08.053] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Transgenic mice expressing exon 1 of the human Huntington's disease (HD) gene carrying a 115 CAG repeat (line R6/1) are characterized by a neurologic phenotype involving molecular, behavioral and motor disturbances. We have characterized the R6/1 to establish a set of biomarkers, which could be semi-quantitatively compared. We have measured motor fore- and hindlimb coordination, fore- and hindpaw footprinting, general activity and anxiety, feetclasping, developmental instability. Molecular investigations involved measurements of cannabinoid receptor 1 mRNA, met-enkephalin peptide, dopamine and cyclic AMP-regulated phosphoroprotein 32 kDa and neuronal inclusions. Molecular and behavioral testing was performed on female hemizygotic R6/1 transgenic mice and female wildtype littermates between 6 and 36 weeks of age. We show that the cannabinoid receptor 1 receptor is severely and rapidly downregulated in the R6/1 mouse between the 8(th) to the 10(th) week of age. At 14 weeks of age the first transgenic mice showed a behavioral phenotype measured by feetclasping. However, there was great variation between the individual animals. At 11 weeks of age the mice demonstrated progressively increasing developmental instability as measured by fluctuating asymmetry. Weight differences were evident by 22 weeks of age. Mice tested at 23 and 24 weeks of age showed significant impairments in open field and plus-maze analysis respectively. We observed no significant abnormalities in stride length of the R6/1 mouse model. As the analyzed parameters are easily detected and measured, the R6/1 mouse appears to be a good model for evaluating new drugs or types of therapy for HD.
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Affiliation(s)
- B Naver
- Section of Neurogenetics, Institute of Medical Biochemistry and Genetics, Dep G, The Panum Institute, University of Copenhagen, Blegdamsvej 3, Building 24.4.24, DK-2200 Copenhagen N, Denmark.
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Olsen AK, Bladbjerg EM, Marckmann P, Larsen LF, Hansen AK. The Göttingen minipig as a model for postprandial hyperlipidaemia in man: experimental observations. Lab Anim 2002; 36:438-44. [PMID: 12396288 DOI: 10.1258/002367702320389116] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Postprandial hyperlipidaemia is believed to be atherogenic. This study aimed to establish a minipig model to investigate determinants of postprandial lipid metabolism. In a randomized cross-over design seven minipigs were subjected to six different feeding regimens: intragastric fat loads of 1, 2, and 4 g fat (Intralipid, 20%) kg(-1) in two fractions 1.5 h apart (1/3 first, 2/3 second), 2 g fat (Intralipid kg(-1) in one fraction, and 2 g olive oil kg(-1) in two fractions, all after pre-feeding with standard diet, and finally 2 g fat (Intralipid kg(-1) in two fractions without pre-feeding. Blood was sampled before and hourly for 7 h after gavaging, and plasma triglycerides were measured. Triglycerides increased significantly in all the feeding regimens (P < 0.001), except when olive oil was used as the fat source. A borderline significant dose-response effect of the Intralipid dose on the triglyceride response was observed. We found no significant differences in triglyceride response whether 2 g fat (Intralipid kg(-1) was given in one or two fractions, with or without pre-feeding. We conclude that postprandial hyperlipidaemia in minipigs can be induced by gavaging an emulgated lipid solution (1-4 g fat/kg, Intralipid, while olive oil is not applicable. There is no need to administer the fat fractionated or to withhold food prior to administration.
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Affiliation(s)
- A K Olsen
- Department for Thrombosis Research, University of Southern Denmark, Ribe County Hospital, Esbjerg, Denmark.
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Abstract
Fluctuating asymmetry, which reflects small, random deviations from symmetry in otherwise bilaterally symmetrical characters, may be used as an indicator of developmental instability in humans and farm animals, and it may also be applicable as a stress indicator. We intended to find a method to allow the use of fluctuating asymmetry as a stress indicator in laboratory animals. That method had to be reproducible and reliable. Furthermore, its applicability in laboratory animals would be improved if it was possible to obtain measurements on the skin surface that correlated with results obtained by measuring the skeleton directly. Seven traits in mice and five traits in rats were evaluated for their applicability for measuring fluctuating asymmetry in mice and rats. Two out of the seven traits, i.e. the width of the joint between the third metatarsal bone and the digital bone on the hind paw, and the length of the incisor tooth at the top, were found to be reliable and reproducible for detecting fluctuating asymmetry in mice as well as in rats. Three out of the seven traits, i.e. the width of the carpal bones, the width of the joint between the tibia and the tarsal bones, and the length of the incisor tooth at the bottom, did express fluctuating asymmetry, but showed a poor day-to-day reproducibility. If the day-to-day reproducibility could be increased, these three traits might also be suitable for measuring fluctuating asymmetry in mice and rats. The last two traits, i.e. the length of ulna and the length of calcaneus plus metatarsal bone i.v., measured both on the skin surface and directly on the bone, did not express fluctuating asymmetry, and had a poor day-to-day reproducibility. These two traits are not suitable for measuring fluctuating asymmetry in mice and rats.
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Affiliation(s)
- C Stub
- Division of Laboratory Animal Science and Welfare, Department of Pharmacology and Pathobiology, Royal Veterinary and Agricultural University, 3 Ridebanevej, DK-1870 Frederiksberg C, Denmark.
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Chapman BE, Anderson JK, Biewer TM, Brower DL, Castillo S, Chattopadhyay PK, Chiang CS, Craig D, Den Hartog DJ, Fiksel G, Fontana PW, Forest CB, Gerhardt S, Hansen AK, Holly D, Jiang Y, Lanier NE, Prager SC, Reardon JC, Sarff JS. Reduced edge instability and improved confinement in the MST reversed-field pinch. Phys Rev Lett 2001; 87:205001. [PMID: 11690477 DOI: 10.1103/physrevlett.87.205001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2001] [Indexed: 05/23/2023]
Abstract
Improved confinement has been achieved in the MST through control of the poloidal electric field, but it is now known that the improvement has been limited by bursts of an edge-resonant instability. Through refined poloidal electric field control, plus control of the toroidal electric field, we have suppressed these bursts. This has led to a total beta of 15% and a reversed-field-pinch-record estimated energy confinement time of 10 ms, a tenfold increase over the standard value which for the first time substantially exceeds the confinement scaling that has characterized most reversed-field-pinch plasmas.
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Affiliation(s)
- B E Chapman
- University of Wisconsin, Madison, Wisconsin 53706, USA.
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Abstract
Pre-analytical handling may be an important determinant of haematological variables, if analysis is delayed. We investigated the effect of anticoagulants, i.e. tripotassium ethylenediamine-tetraacetic acid (EDTA) and citric acid, theophylline, adenosine, dipyridamole (CTAD), storage time (0.5, 1.5, 3.5, 5.5, 7.5, 25.5 and 27.5 h after blood sampling), and storage temperature (5 degrees C and 20 degrees C) on the variation in haemoglobin (HGB), red blood cell count (RBC), haematocrit (HCT), white blood cell count (WBC), and platelet count (PLT) in minipigs. Medians of HGB, RBC, HCT, WBC and PLT were significantly higher in EDTA tubes than in CTAD tubes due to the dilution effect of the anticoagulant. We found a minor significant increase in HCT after 25.5 h in blood stored at 20 degrees C, and at the same time a minor significant increase in WBC in EDTA tubes stored at 20 degrees C. We found a significant decrease in PLT in blood stored at 5 degrees C, especially in EDTA tubes. Minor variations were also observed in HGB and RBC. Our results indicate that PLT should only be measured in tubes placed at room temperature. If HCT or WBC analyses are to be performed on the day after blood sampling, the samples must be stored in a refrigerator until analysis. Our studies underline that time delay before analysis of haematological variables can cause increased variation, and should therefore be limited as far as possible in order to reduce the number of animals needed to make reliable conclusions.
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Affiliation(s)
- A K Olsen
- Department of Thrombosis Research, University of Southern Denmark, Esbjerg.
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Olsen AK, Larsen LF, Bladbjerg EM, Hansen AK, Jespersen J, Marckmann P. A high-fat meal does not activate blood coagulation factor VII in minipigs. Blood Coagul Fibrinolysis 2001; 12:117-22. [PMID: 11302473 DOI: 10.1097/00001721-200103000-00005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
It is a matter of debate whether postprandial activation of blood coagulation factor VII (FVII) is associated with an increased risk of thrombosis. To clarify this question, an animal model in which consequences of dietary FVII activation can be studied in a more detailed way would be an important tool. We studied postprandial FVII activation in seven non-fasting Göttingen minipigs. Intralipid (4 g/kg) was administered through a gastric tube in two fractions at 9.00 a.m. (one-third of total dose) and 10.30 a.m. (two-thirds of total dose). Blood samples were drawn 0.5 h before (baseline) and 2, 3, 3.5, 4, 5, and 6 h after the first fat load. Triglycerides, activated FVII (FVIIa), FVII coagulant activity (FVIIc), FVII amidolytic activity (FVIIam) and prothrombin fragment I + 2 (F1 + 2) were analysed in plasma samples. Median plasma triglycerides were significantly raised from 0.67 mmol/l (baseline) to 2.56 mmol/l 5 h postprandially (P < 0.001). There were no significant changes in FVIIa (9.6 U/l at baseline), FVIIam (142% at baseline) and F1 + 2 (0.13 nmol/l at baseline). FVIIc decreased from 141% at baseline to 114% 6 h postprandially (P < 0.001). As a high-fat meal does not seem to activate blood coagulation FVII in minipigs, the pig is apparently not a relevant model for the study of dietary FVII activation and thrombin generation.
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Affiliation(s)
- A K Olsen
- Department of Thrombosis Research, University of Southern Denmark.
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Jørgensen KH, Hansen AK, Buschard K. Five fold increase of insulin concentration delays the absorption of subcutaneously injected human insulin suspensions in pigs. Diabetes Res Clin Pract 2000; 50:161-7. [PMID: 11106830 DOI: 10.1016/s0168-8227(00)00196-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Human NPH U100 (100 IU/ml), given once daily, is often absorbed too fast to cover the basal insulin demand throughout 24 h. The aim of the present study was to examine whether the absorption of human insulin suspensions would be delayed by increasing the insulin concentration from U100 to U500. In each experiment 10 IU of corresponding human Ul00 and U500 preparations, labelled with 125I-insulin, were injected subcutaneously and contralaterally in the neck of a pig followed by monitoring residual radioactivity over the injection sites. The time until 75, 50 and 25% residual radioactivity (T(75%), T(50%) and T(25%)) using NPH U500 was compared with NPH U100 in 14 experiments: T(75%): 5.0+/-0.5 (mean+/-SEM) vs 3.8+/-0.3 h (P=0.007, paired t-test), T(50%): 12. 2+/-0.9 vs 9.0+/-0.6 h (P=0.003) and T(25%). 24.2+/-1.2 vs 17.9+/-1. 2 h (P=0.001). The corresponding values for semilente U500 compared with semilente U100 in eight experiments were: T(75%): 2.8+/-0.4 vs 1.6+/-0.2 h (P=0.02), T(50%): 5.6+/-0.6 vs 3.4+/-0.3 h (P=0.01) and T(25%): 10.9+/-1.1 vs 7.2+/-0.7 h (P=0.009). Thus, the absorption of a given dose of human NPH or human semilente insulin in pigs is substantially delayed by changing the insulin concentration from Ul00 to U500. Human NPH U500 appears to be more appropriate than human NPH U100 for injection once daily in basal insulin therapy.
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Affiliation(s)
- K H Jørgensen
- Bartholin Instituttet, Kommunehospitalet, DK-1399, Copenhagen, Denmark.
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Hansen AK, Almagri AF, Craig D, Hegna CC, Prager SC, Sarff JS. Momentum transport from nonlinear mode coupling of magnetic fluctuations. Phys Rev Lett 2000; 85:3408-3411. [PMID: 11030908 DOI: 10.1103/physrevlett.85.3408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2000] [Indexed: 05/23/2023]
Abstract
A cause of observed anomalous plasma momentum transport in a reversed-field pinch is determined experimentally. Magnetohydrodynamic theory predicts that nonlinear interactions involving triplets of tearing modes produce internal torques that redistribute momentum. Evidence for the nonlinear torque is acquired by detecting the correlation of momentum redistribution with the mode triplets, with the elimination of one of the modes in the triplet, and with the external driving of one of the modes.
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Affiliation(s)
- AK Hansen
- University of Wisconsin Department of Physics,1150 University Avenue, Madison, Wisconsin 53706, USA
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Abstract
Antiobiogrammes were made of a number of isolates of Staphylococcus aureus, Escherichia coli and Pasteurella pneumotropica derived from rodent, rabbit or minipig colonies never treated with antibiotics. For S. aureus no differences between rats and mice were found in the percentage of resistant isolates. Gentamicin and erythromycin were found to be the most efficient, while the highest percentages of resistance were found to be against penicillins and sulphonamides. In general, the results from antibiogrammes on E. coli were rather uniform, with only slight differences between isolates from different species, except that more vancomycin and tetracycline-resistant minipig isolates were found. In almost all isolates of E. coli, resistance was shown against penicillin, fucidin, macrolides, lincosamides and tiamulin. For a number of antibiotics, mouse isolates of P. pneumotropica were more frequently found to be sensitive than rat isolates. The resistance patterns of E. coli from the minipigs were quite similar to resistance patterns found in farm pigs, but apart from this, the resistance patterns of the bacterial species tested did not resemble human or farm animal patterns in any of the animal species, and, therefore, these studies do not support the theory that S. aureus and E. coli in laboratory animal colonies derive from the normal flora of the human caretakers. The fact that rodent species of E. coli, in contrast to human and farm animal species, are sensitive to ampicillin, tetracyclines, and the combination of sulphonamides and trimethoprim, might be due to the fact that these antibiotics are not used in rodent populations.
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Affiliation(s)
- A K Hansen
- Department of Pharmacology and Pathobiology, Royal Veterinary and Agricultural University, Frederiksberg, Denmark
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Iida H, Law I, Pakkenberg B, Krarup-Hansen A, Eberl S, Holm S, Hansen AK, Gundersen HJ, Thomsen C, Svarer C, Ring P, Friberg L, Paulson OB. Quantitation of regional cerebral blood flow corrected for partial volume effect using O-15 water and PET: I. Theory, error analysis, and stereologic comparison. J Cereb Blood Flow Metab 2000; 20:1237-51. [PMID: 10950386 DOI: 10.1097/00004647-200008000-00009] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Limited spatial resolution of positron emission tomography (PET) can cause significant underestimation in the observed regional radioactivity concentration (so-called partial volume effect or PVE) resulting in systematic errors in estimating quantitative physiologic parameters. The authors have formulated four mathematical models that describe the dynamic behavior of a freely diffusible tracer (H215O) in a region of interest (ROI) incorporating estimates of regional tissue flow that are independent of PVE. The current study was intended to evaluate the feasibility of these models and to establish a methodology to accurately quantify regional cerebral blood flow (CBF) corrected for PVE in cortical gray matter regions. Five monkeys were studied with PET after IV H2(15)O two times (n = 3) or three times (n = 2) in a row. Two ROIs were drawn on structural magnetic resonance imaging (MRI) scans and projected onto the PET images in which regional CBF values and the water perfusable tissue fraction for the cortical gray matter tissue (hence the volume of gray matter) were estimated. After the PET study, the animals were killed and stereologic analysis was performed to assess the gray matter mass in the corresponding ROIs. Reproducibility of the estimated parameters and sensitivity to various error sources were also evaluated. All models tested in the current study yielded PVE-corrected regional CBF values (approximately 0.8 mL x min(-1) x g(-1) for models with a term for gray matter tissue and 0.5 mL x min(-1) x g(-1) for models with a term for a mixture of gray matter and white matter tissues). These values were greater than those obtained from ROIs tracing the gray matter cortex using conventional H2(15)O autoradiography (approximately 0.40 mL x min(-1) x g(-1)). Among the four models, configurations that included two parallel tissue compartments demonstrated better results with regards to the agreement of tissue time-activity curve and the Akaike's Information Criteria. Error sensitivity analysis suggested the model that fits three parameters of the gray matter CBF, the gray matter fraction, and the white matter fraction with fixed white matter CBF as the most reliable and suitable for estimating the gray matter CBF. Reproducibility with this model was 11% for estimating the gray matter CBF. The volume of gray matter tissue can also be estimated using this model and was significantly correlated with the results from the stereologic analysis. However, values were significantly smaller compared with those measured by stereologic analysis by 40%, which can not be explained by the methodologic errors. In conclusion, the partial volume correction was essential in quantitation of regional CBF. The method presented in this article provided the PVE-corrected regional CBF in the cortical gray matter tissue. This study also suggests that further studies are required before using MRI derived anatomic information for PVE correction in PET.
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Affiliation(s)
- H Iida
- The Neurobiology Research Unit, The Copenhagen University Hospital, Rigshospitalet, Denmark
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Abstract
Two indirect immunofluorescence (IIF) assays, two enzyme-linked immunosorbent assays (ELISAs) and the carbon immunoassay (CIA) for determination of antibodies to Encephalitozoon cuniculi were compared using 210 sera of rabbits, 135 of which originated from seven infected colonies, while 75 originated from four uninfected colonies. There was no evidence of a difference between the different assays with respect to the number of positive sera. There was a clear correlation between the quantitative response measured by IIF and CIA and the other assays, and between both IIF tests, while no such correlation was found in the quantitative response measured by ELISAs, which might be explained by the less quantitative nature of the ELISA. Therefore quantitative determination of antibodies to E. cuniculi should be performed by IIF and not by ELISA. The nosographic sensitivities N1 and specificities N2 of the assays were > or = 0.94 and > or = 0.97 respectively. Small differences in N1 and N2 between the assays, although not statistically significant, were responsible for differences in the calculated predictive values of a positive test and of a negative test. As expected, the magnitude of these differences depended on the fraction of positive sera sampled from a given colony. There was strong evidence of such a difference between the fraction of positive sera found in different colonies, but the sample size from some colonies was too small to allow any conclusion, whether this was due to differences in the prevalences of the infection in the colonies or something else. We conclude that any of the assays will be suitable for the routine health monitoring of laboratory rabbit colonies for E. cuniculi infection, as recommended by the Federation of European Laboratory Animal Science Associations.
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Affiliation(s)
- R Boot
- Section of Laboratory Animal Microbiology, LIS, National Institute of Public Health and the Environment (RIVM), Bilthoven, The Netherlands
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Schou S, Hansen AK. Marburg and Ebola virus infections in laboratory non-human primates: a literature review. Comp Med 2000; 50:108-23. [PMID: 10857001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
BACKGROUND AND PURPOSE Several non-human primate species are used as laboratory animals for various types of studies. Although importation of monkeys may introduce different diseases, special attention has recently been drawn to Marburg and Ebola viruses. This review presented here discusses the potential risk of these viruses for persons working with non-human primates as laboratory animals by focusing on epidemiology, virology, symptoms, pathogenesis, natural reservoir, transmission, quarantine of non-human primates, therapy, and prevention. CONCLUSION A total of 23 Marburg and Ebola virus outbreaks causing viral hemorrhagic fever has been reported among humans and monkeys since the first outbreak in Marburg, Germany in 1967. Most of the 1,100 human cases, with nearly 800 deaths, developed in Africa due mainly to direct and intimate contact with infected patients. Few human cases have developed after contact with non-human primates used for various scientific purposes. However, adequate quarantine should be applied to prevent human infections not only due to Marburg and Ebola viruses, but also to other infective agents. By following proper guidelines, the filovirus infection risk for people working with non-human primates during quarantine exists, but is minimal. There seems to be little risk for filovirus infections after an adequate quarantine period. Therefore, non-human primates can be used as laboratory animals, with little risk of filovirus infections, provided adequate precautions are taken.
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Affiliation(s)
- S Schou
- Department of Oral Surgery, School of Dentistry, Faculty of Health Sciences, University of Copenhagen and University Hospital (Rigshospitalet), Denmark
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Abstract
Attempts were made to clarify whether laboratory guineapigs may harbour a poliovirus which, in 1911, was described as the cause of a disease called guineapig lameness. By the use of ELISA for antibodies against the poliovirus, Theiler's murine encephalomyelitis virus (TMEV), it was shown that two pet shop guineapigs suffering from lameness had extremely high titres against poliovirus, while healthy guineapigs from the same pet shop were negative. Clearly positive results were also found in 35 out of 152 laboratory guineapig sera. Positive results were found in only two out of six breeding centres, but in three out of three experimental units, all of which purchased guineapigs from one of the seropositive breeding colonies. The diseased guineapigs recovered fully after treatment with vitamins in the drinking water, a treatment used for guineapig lameness by small animal practitioners. A theory that vitamin C deficient guineapigs are, due to an impaired steroid secretion, predisposed to succumbing to infection and develop demyelinating disease similar to that in TMEV infected mice is discussed briefly. Guineapig sera were also tested serologically for other infections. Antibodies against lymphocytic choriomeningitis virus, Clostridium piliforme and Toxoplasma gondii were not found, but one breeding colony was infected with adenovirus, pneumonia virus of mice, reovirus type 3, Sendai virus, parainfluenza (simian) virus type 5 and Encephalitozoon cuniculi. Two other breeding colonies were infected with both reovirus type 3 and E. cuniculi. In all three experimental units infection with adenovirus was observed, and in two of these Sendai virus and E. cuniculi antibodies were also found. The pet shop guineapigs were infected with adenovirus, reovirus type 3 and E. cuniculi.
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Affiliation(s)
- A K Hansen
- Department of Experimental Medicine, University of Copenhagen, Denmark.
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