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861.
The harp seal Pagophilus groenlandicus is a major high trophic level predator in the Barents Sea, and to better understand their function in the Barents Sea ecosystem, we need to understand their foraging behaviour during their most intensive feeding period. We analysed the diet composition and prey preference of 184 harp seals and 94 faeces samples, sampled in the northern Barents Sea (around Svalbard) during the period May–August in 1996, 1997, and 2004–2006. Concurrent with the sampling of seals, prey availability was assessed in one area in 1996 and 1997 and in two areas in 2006 using standard acoustic methods. Our study showed that harp seal diet composition varied significantly both in time (year) and space, and that their diets appeared to be size dependent. Both subadult (<150 cm) and adult seals were associated with pelagic crustaceans (particularly krill), whereas primarily adult seals were associated with fish (capelin, gadoids and flatfish). Krill was the most important prey group (63 %) followed by polar cod (16 %) and other fish species (10 %). The prey preference of harp seals varied in time and space; polar cod was often preferred by the seals whereas krill was commonly consumed in lower proportion than observed in the survey area. Gadoids and capelin had either been exploited in the same or less proportion as observed in the survey sea. This study emphasises the ecological significance of krill as prime food for harp seals during their intensive feeding period in summer. 相似文献
862.
Lars Tore Gyland Mikalsen Hari Prasad Dhakal ?yvind S. Bruland Bj?rn Naume Elin Borgen Jahn M. Nesland Dag Rune Olsen 《PloS one》2013,8(10)
Angiogenesis quantification, through vessel counting or area estimation in the most vascular part of the tumour, has been found to be of prognostic value across a range of carcinomas, breast cancer included. We have applied computer image analysis to quantify vascular properties pertaining to size, shape and spatial distributions in photographed fields of CD34 stained sections. Aided by a pilot (98 cases), seven parameters were selected and validated on a separate set from 293 breast cancer patients.Two new prognostic markers were identified through continuous Cox regression with endpoints Breast Cancer Specific Survival and Distant Disease Free Survival: The average size of the vessels as measured by their perimeter (p = 0.003 and 0.004, respectively), and the average complexity of the vessel shapes measured by their solidity (p = 0.004 and 0.004). The Hazard ratios for the corresponding median-dichotomized markers were 2.28 (p = 0.005) and 1.89 (p = 0.016) for the mean perimeter and 1.80 (p = 0.041) and 1.55 (p = 0.095) for the shape complexity. The markers were associated with poor histologic type, high grade, necrosis, HR negativity, inflammation, and p53 expression (vessel size only).Both markers were found to strongly influence the prognostic properties of vascular invasion (VI) and disseminated tumour cells in the bone marrow. The latter being prognostic only in cases with large vessels (p = 0.004 and 0.043) or low complexity (p = 0.018 and 0.024), but not in the small or complex vessel groups (p>0.47). VI was significant in all groups, but showed greater hazard ratios for small and low complexity vessels (6.54–11.2) versus large and high complexity vessels (2.64–3.06).We find that not only the overall amount of produced vasculature in angiogenic hot-spots is of prognostic significance, but also the morphological appearance of the generated vessels, i.e. the size and shape of vessels in the studied hot spots. 相似文献
863.
864.
Karen Fjeldborg Tore Christiansen Marianne Bennetzen Holger J. Møller Steen B. Pedersen Bjørn Richelsen 《Obesity (Silver Spring, Md.)》2013,21(12):2437-2443
Objective: Soluble CD163 (sCD163) is a new macrophage‐specific serum marker elevated in inflammatory conditions. sCD163 is elevated in obesity and found to be a strong predictor of the development of type 2 diabetes. We investigated whether dietary intervention and moderate exercise was related to changes in sCD163 and how sCD163 is associated to insulin resistance in obesity. Design and Methods: Ninety‐six obese subjects were enrolled: 62 followed a very low energy diet (VLED) program for 8 weeks followed by 3‐4 weeks of weight stabilization, 20 followed a moderate exercise program for 12 weeks, and 14 were included without any intervention. Fasting blood samples and anthropometric measures were taken at baseline and after intervention. Thirty‐six lean subjects were included in a control group. Results: sCD163 was significantly higher in obese subjects (2.3 ± 1.0 mg/l) compared with lean (1.6 ± 0.4 mg/l, P < 0.001). Weight loss (11%) induced by VLED resulted in a reduction and partial normalization of sCD163 to 2.0 ± 0.9 mg/l (P < 0.001). Exercise for 12 weeks had no effect on sCD163. At baseline, sCD163 was significantly correlated with BMI (r = 0.46), waist circumference (r = 0.40), insulin resistance measured by the homeostasis model assessment (HOMA‐IR; r = 0.41; all P < 0.001), and the leptin‐to‐adiponectin ratio (r = 0.28, P < 0.05). In a multivariate linear regression analysis with various inflammatory markers, sCD163 (β = 0.25), adiponectin (β = ?0.24), and high sensitivity C‐reactive protein (hs‐CRP; β = 0.20) remained independently and significantly associated to HOMA‐IR (all P < 0.05). After further adjustment for waist circumference, only sCD163 was associated with HOMA‐IR (P < 0.05). Conclusion: The macrophage‐specific serum marker sCD163 is increased in obesity and partially normalized by dietary‐induced weight loss but not by moderate exercise. Furthermore, we confirm that sCD163 is a good marker for obesity‐related insulin resistance. 相似文献
865.
Marthe T. Maehlen Sella A. Provan Diederik P. C. de Rooy Annette H. M. van der Helm - van Mil Annemarie Krabben Tore Saxne Elisabet Lindqvist Anne Grete Semb Till Uhlig Désirée van der Heijde Inger Lise Mero Inge C. Olsen Tore K. Kvien Benedicte A. Lie 《PloS one》2013,8(4)
Objective
Apolipoprotein E (APOE) genotypes are associated with cardiovascular disease (CVD) and lipid levels. In rheumatoid arthritis (RA), an association has been found with disease activity. We examined the associations between APOE genotypes and disease susceptibility and markers of disease severity in RA, including radiographic joint damage, inflammatory markers, lipid levels and cardiovascular markers.Method
A Norwegian cohort of 945 RA patients and 988 controls were genotyped for two APOE polymorphisms. We examined longitudinal associations between APOE genotypes and C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) as well as hand radiographs (van der Heijde Sharp Score(SHS)) in 207 patients with 10 year longitudinal data. Lipid levels, cardiovascular markers and history of CVD were compared across genotypes in a cross sectional study of 136 patients. Longitudinal radiological data of cohorts from Lund and Leiden were available for replication. (N = 935, with 4799 radiographs).Results
In the Norwegian cohort, associations between APOE genotypes and total cholesterol (TC) and low-density lipoproteins (LDL) were observed (ε2<ε3/ε3<ε4, p = 0.03 and p = 0.02, respectively). No association was present for acute phase reactant or CVD markers, but a longitudinal linear association between APOE genotypes and radiographic joint damage was observed (p = 0.007). No association between APOE genotypes and the severity of joint destruction was observed in the Lund and Leiden cohorts, and a meta- analysis combining all data was negative.Conclusion
APOE genotypes are associated with lipid levels in patients with RA, and may contribute to dyslipidemia in some patients. APOE genotypes are not consistently associated with markers of inflammation or joint destruction in RA. 相似文献866.
Background
Haptocorrin (HC) carries cobalamin analogues (CorA), but whether CorA are produced in the body is unknown. All cobalamins (Cbl) to the foetus are delivered by the Cbl-specific protein transcobalamin (TC), and therefore analysis of cord serum for CorA may help to clarify the origin of CorA.Methods
HC-CorA were quantified in paired samples of cord serum from newborns and serum from mothers (n = 69).Results
The CorA-concentration was higher in cord serum (median = 380, range: 41–780 pmol/L) than in serum from the mothers (median = 160, range: 64–330 pmol/L), (p<0.0001). HPLC-analysis showed CorA-peaks with retention times of 13.5, 14,5 and 16.5 min in samples from both the mother and cord serum. The peak with retention time 16.5 min constituted 24% (mother) and 45% (cord serum) of the total amount CorA, and eluted as does dicyanocobinamide.Conclusion
Our results support that CorA in the human body are derived from Cbl. 相似文献867.
Ola Johnsson Jonas Andersson Gunnar Lidén Charlotta Johnsson Tore Hägglund 《Biotechnology progress》2013,29(3):817-824
A new strategy for controlling substrate feed in the exponential growth phase of aerated fed‐batch fermentations is presented. The challenge in this phase is typically to maximize specific growth rate while avoiding the accumulation of overflow metabolites which can occur at high substrate feed rates. In the new strategy, regular perturbations to the feed rate are applied and the proximity to overflow metabolism is continuously assessed from the frequency spectrum of the dissolved oxygen signal. The power spectral density for the frequency of the external perturbations is used as a control variable in a controller to regulate the substrate feed. The strategy was implemented in an industrial pilot scale fermentation set up and calibrated and verified using an amylase producing Bacillus licheniformis strain. It was shown that a higher biomass yield could be obtained without excessive accumulation of harmful overflow metabolites. The general applicability of the strategy was further demonstrated by implementing the controller in another process using a Bacillus licheniformis strain currently used in industrial production processes. In addition, in this case a higher growth rate and decreased accumulation of overflow metabolites in the exponential growth phase was achieved in comparison to the reference controller. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:817–824, 2013 相似文献
868.
Alignment-Independent Comparisons of Human Gastrointestinal Tract Microbial Communities in a Multidimensional 16S rRNA Gene Evolutionary Space 总被引:1,自引:0,他引:1
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Knut Rudi Monika Zimonja Bente Kvenshagen Jarle Rugtveit Tore Midtvedt Merete Eggesb 《Applied microbiology》2007,73(8):2727-2734
We present a novel approach for comparing 16S rRNA gene clone libraries that is independent of both DNA sequence alignment and definition of bacterial phylogroups. These steps are the major bottlenecks in current microbial comparative analyses. We used direct comparisons of taxon density distributions in an absolute evolutionary coordinate space. The coordinate space was generated by using alignment-independent bilinear multivariate modeling. Statistical analyses for clone library comparisons were based on multivariate analysis of variance, partial least-squares regression, and permutations. Clone libraries from both adult and infant gastrointestinal tract microbial communities were used as biological models. We reanalyzed a library consisting of 11,831 clones covering complete colons from three healthy adults in addition to a smaller 390-clone library from infant feces. We show that it is possible to extract detailed information about microbial community structures using our alignment-independent method. Our density distribution analysis is also very efficient with respect to computer operation time, meeting the future requirements of large-scale screenings to understand the diversity and dynamics of microbial communities. 相似文献
869.
Salcedo Claudia Wagner Antonie Andersen Jens V. Vinten Kasper Tore Waagepetersen Helle S. Schousboe Arne Freude Kristine K. Aldana Blanca I. 《Neurochemical research》2021,46(10):2676-2686
Neurochemical Research - Alterations in neurotransmitter homeostasis, primarily of glutamate and GABA, is strongly implicated in the pathophysiology of Alzheimer’s disease (AD). Homeostasis... 相似文献
870.
Kristofer Andréasson Tore Saxne Agneta Scheja Izabela Bartosik Thomas Mandl Roger Hesselstrand 《Arthritis research & therapy》2014,16(1):R46