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91.
Agneta Egenvall Ane Nødtvedt Johanna Penell Lotta Gunnarsson Brenda N Bonnett 《Acta veterinaria Scandinavica》2009,51(1):42
The primary aim of this article is to review the use of animal health insurance data in the scientific literature, especially
in regard to morbidity or mortality in companion animals and horses. Methods and results were compared among studies on similar
health conditions from different nations and years. A further objective was to critically evaluate benefits and limitations
of such databases, to suggest ways to maximize their utility and to discuss the future use of animal insurance data for research
purposes. Examples of studies on morbidity, mortality and survival estimates in dogs and horses, as well as neoplasia in dogs,
are discussed. 相似文献
92.
Mari T. Jönsson Alejandro Ruete Olle Kellner Urban Gunnarsson Tord Snäll 《Biodiversity and Conservation》2017,26(11):2547-2567
Incorporating functional values in biodiversity monitoring systems could add novel perspectives of the status of biodiversity in conservation areas. Stable frequencies of large foliose nitrogen-fixing cyanolichens likely have positive effects on the nitrogen budget of forests and provide food, material and shelter for invertebrates, gastropods and birds. Stable volumes of deadwood and frequencies of associated fungi provide an important supporting function for ecosystem services such as nutrient cycling, carbon storage and soil formation. Based on regional monitoring data from boreal old-growth forest nature reserves and key habitats, we tested for changes in the frequency of various functionally important substrates and species over time. We detected significant reductions in the frequency of indicator cyanolichens occurring on deciduous trees already after 10 years in key habitats, despite non-significant changes in their host substrates. Frequencies of indicator pendulous lichens Alectoria sarmentosa and Bryoria nadvornikiana had also decreased in key habitats, despite overall stable volumes of large conifer host trees. Lichen reductions were more pronounced in the smaller key habitats compared to the larger formally protected nature reserves, likely due to degrading fragmentation and isolation effects. In contrast to these lichens, the average frequencies of old-growth forest indicator fungi decaying coniferous deadwood and common fungi on deciduous trees (Fomes fomentarius) and coniferous trees (Fomitopsis pinicola) remained unchanged. The studied cyanolichens and fruiting fungi generally had similar extinction rates over 10 years, whilst only cyanolichens had substantially lower colonization rates. Amid a severely fragmented landscape, conservation areas seem to struggle in preserving some of the basic old-growth forest values. 相似文献
93.
Identification of the yellow skin gene reveals a hybrid origin of the domestic chicken 总被引:3,自引:0,他引:3
Eriksson J Larson G Gunnarsson U Bed'hom B Tixier-Boichard M Strömstedt L Wright D Jungerius A Vereijken A Randi E Jensen P Andersson L 《PLoS genetics》2008,4(2):e1000010
Yellow skin is an abundant phenotype among domestic chickens and is caused by a recessive allele (W*Y) that allows deposition of yellow carotenoids in the skin. Here we show that yellow skin is caused by one or more cis-acting and tissue-specific regulatory mutation(s) that inhibit expression of BCDO2 (beta-carotene dioxygenase 2) in skin. Our data imply that carotenoids are taken up from the circulation in both genotypes but are degraded by BCDO2 in skin from animals carrying the white skin allele (W*W). Surprisingly, our results demonstrate that yellow skin does not originate from the red junglefowl (Gallus gallus), the presumed sole wild ancestor of the domestic chicken, but most likely from the closely related grey junglefowl (Gallus sonneratii). This is the first conclusive evidence for a hybrid origin of the domestic chicken, and it has important implications for our views of the domestication process. 相似文献
94.
Gunnarsson M Frängsmyr L Stigbrand T Jensen PE 《Protein expression and purification》2003,27(2):238-243
The human alpha(2)-macroglobulin gene is approximately 48 kb in size and consists of 36 exons, which encode the 180 kDa subunit of this large tetrameric protein. In this investigation, a procedure of sequencing human alpha(2)-macroglobulin mRNA, using mRNA from lipopolysaccharide-stimulated peripheral blood mononuclear cells as template in RT-PCR, was developed. Incubation of peripheral blood mononuclear cell populations with lipopolysaccharide induced alpha(2)-macroglobulin mRNA expression reaching levels detectable by RT-PCR. Extracted human alpha(2)-macroglobulin mRNA was used to determine the nucleotide sequence of a 500 bp DNA segment encoding the most C-terminal, receptor-binding part of the protein, using alpha(2)-macroglobulin specific primers. The sequence obtained matched the earlier published sequence of human alpha(2)-macroglobulin, except for three point mutations, i.e., cytosine for guanine, cytosine for thymidine and thymidine for adenine substitutions at positions 4369, 4423, and 4511, respectively. None of these alterations, however, affect the amino acid sequence of the protein. In conclusion, we demonstrate a new, improved, approach to sequence human alpha(2)-macroglobulin mRNA by overexpressing the protein in peripheral blood mononuclear cells. This procedure may be useful in the search for mutations in alpha(2)-macroglobulin, examining its role in the pathogenesis of human diseases. 相似文献
95.
Edman K Eriksson B Svensson L Gunnarsson PO 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,785(2):311-316
Laquinimod is an immunomodulator that is currently in clinical trials. For pharmacokinetic and toxicokinetic studies in animals and humans a sensitive and accurate bioanalytical method was required. In this paper a bioanalytical method for the determination of laquinimod by liquid chromatography is described. After a protein precipitation step the plasma sample was injected onto a coupled-column HPLC system. After further purification from macromolecules on a short restricted access material C(18) column the analyte was transferred to a reversed-phase C(18) analytical column and separated from interfering substances. The analyte was detected by UV detection. The method was validated with respect to linearity, selectivity, precision, accuracy, limit of quantitation, limit of detection, recovery and stability. The limit of quantitation was 0.75 micromol/L, the intermediate precision was 1.8-3.6% (C.V.) and the accuracy was 97.7-114.7%. In conclusion, the method was found to perform well and is suitable for use in pharmacokinetic and toxicokinetic studies. 相似文献
96.
Gunnarsson N Bruheim P Nielsen J 《Journal of industrial microbiology & biotechnology》2003,30(3):150-156
Nonomuraea sp. ATCC 39727 is a novel actinomycete species and the producer of A40926, a glycopeptide antibiotic structurally similar
to teichoplanin. In the present study, a defined minimal medium was designed for Nonomuraea fermentation. The influence of initial phosphate, glucose and ammonium concentrations on antibiotic productivity was investigated
in batch fermentation and the effect of glucose limitation was studied in fed-batch fermentation. It was found that low initial
concentrations of phosphate and ammonium are beneficial for A40926 production and that productivity is not enhanced during
glucose limitation. Furthermore, the initiation of A40926 production was not governed by residual ammonium and phosphate concentrations,
although the level of these nutrients strongly influenced A40926 production rates and final titers.
Electronic Publication 相似文献
97.
98.
Fine mapping of the SLEB2 locus involved in susceptibility to systemic lupus erythematosus 总被引:6,自引:0,他引:6
Magnusson V Lindqvist AK Castillejo-López C Kristjánsdottir H Steinsson K Gröndal G Sturfelt G Truedsson L Svenungsson E Lundberg I Gunnarsson I Bolstad AI Haga HJ Jonsson R Klareskog L Alcocer-Varela J Alarcón-Segovia D Terwilliger JD Gyllensten UB Alarcón-Riquelme ME 《Genomics》2000,70(3):307-314
We have previously reported linkage of systemic lupus erythematosus to chromosome 2q37 in multicase families from Iceland and Sweden. This locus (SLEB2) was identified by linkage to the markers D2S125 and D2S140. In the present study we have analyzed additional microsatellite markers and SNPs covering a region of 30 cM around D2S125 in an extended set of Nordic families (Icelandic, Swedish, and Norwegian). Two-point linkage analysis in these families gave a maximum lod score at the position of markers D2S2585 and D2S2985 (Z = 4.51, PIC = 0.65), by applying a "model-free" pseudo-marker linkage analysis. Based on multipoint linkage analysis in the Nordic families, the most likely location of the SLEB2 locus is estimated to be in the interval between D2S125 and the position of markers D2S2585 and D2S2985, with a peak multipoint lod score of Z = 6.03, assuming a dominant pseudo-marker model. Linkage disequilibrium (LD) analysis was performed using the data from the multicase families and 89 single-case families of Swedish origin, using the same set of markers. The LD analysis showed evidence for association in the single-case and multicase families with locus GAAT3C11 (P < 0.0003), and weak evidence for association was obtained for several markers located telomeric to D2S125 in the multicase families. Thirteen Mexican families were analyzed separately and found not to have linkage to this region. Our results support the presence of the SLEB2 locus at 2q37. 相似文献
99.
Migration is fundamental in the life of many birds and entails significant energetic and time investments. Given the importance of arrival time in the breeding area and the relatively short period available to reproduce (particularly at high latitudes), it is expected that birds reduce spring migration duration to a greater extent than autumn migration, assuming that pressure to arrive into the wintering area might be relaxed. This has previously been shown for several avian groups, but recent evidence from four tracked Icelandic whimbrels Numenius phaeopus islandicus, a long distance migratory wader, suggests that this subspecies tends to migrate faster in autumn than in spring. Here, we 1) investigate differences in seasonal migration duration, migration speed and ground speed of whimbrels using 56 migrations from 19 individuals tracked with geolocators and 2) map the migration routes, wintering and stopover areas for this population. Tracking methods only provide temporal information on the migration period between departure and arrival. However, migration starts with the fuelling that takes place ahead of departure. Here we estimate the period of first fuelling using published fuel deposition rates and thus explore migration speed using tracking data. We found that migration duration was shorter in autumn than in spring. Migration speed was higher in autumn, with all individuals undertaking a direct flight to the wintering areas, while in spring most made a stopover. Wind patterns could drive whimbrels to stop in spring, but be more favourable during autumn migration and allow a direct flight. Additionally, the stopover might allow the appraisal of weather conditions closer to the breeding areas and/or improve body condition in order to arrive at the breeding sites with reserves. 相似文献
100.
Anna Gillman Shaman Muradrasoli Hanna S?derstr?m Fredrik Holmberg Neus Latorre-Margalef Conny Tolf Jonas Waldenstr?m Gunnar Gunnarsson Bj?rn Olsen Josef D. J?rhult 《Applied and environmental microbiology》2015,81(7):2378-2383
Influenza A virus (IAV) has its natural reservoir in wild waterfowl, and emerging human IAVs often contain gene segments from avian viruses. The active drug metabolite of oseltamivir (oseltamivir carboxylate [OC]), stockpiled as Tamiflu for influenza pandemic preparedness, is not removed by conventional sewage treatment and has been detected in river water. There, it may exert evolutionary pressure on avian IAV in waterfowl, resulting in the development of resistant viral variants. A resistant avian IAV can circulate among wild birds only if resistance does not restrict viral fitness and if the resistant virus can persist without continuous drug pressure. In this in vivo mallard (Anas platyrhynchos) study, we tested whether an OC-resistant avian IAV (H1N1) strain with an H274Y mutation in the neuraminidase (NA-H274Y) could retain resistance while drug pressure was gradually removed. Successively infected mallards were exposed to decreasing levels of OC, and fecal samples were analyzed for the neuraminidase sequence and phenotypic resistance. No reversion to wild-type virus was observed during the experiment, which included 17 days of viral transmission among 10 ducks exposed to OC concentrations below resistance induction levels. We conclude that resistance in avian IAV that is induced by exposure of the natural host to OC can persist in the absence of the drug. Thus, there is a risk that human-pathogenic IAVs that evolve from IAVs circulating among wild birds may contain resistance mutations. An oseltamivir-resistant pandemic IAV would pose a substantial public health threat. Therefore, our observations underscore the need for prudent oseltamivir use, upgraded sewage treatment, and surveillance for resistant IAVs in wild birds. 相似文献