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Two trials with Atlantic salmon ( Salmo salar) were conducted to evaluate the potential of krill meal to improve feed intake. In the first experiment, after transfer to sea water, salmon smolts were fed diets added 75 or 150 g kg−1 Antarctic krill meal in substitution for fish meal for 13 weeks. The apparent digestibility coefficient for crude protein and the majority of the amino acids was significantly lower in the feeds added krill meal (around 83.5%) than in the control diet (84.9%), whereas the digestibility of crude lipids, dry matter and energy was not significantly different among the three diets. Krill meal addition resulted in higher feed intake, which led to higher growth rates and final body weights. In the second experiment, large salmon were fed a diet containing 100 g kg−1 krill meal for 6 weeks before slaughter. Their feed intake and growth performance were assessed, and fillet and visceral fat contents were measured. Salmon fed the 100 g kg−1 krill meal diet tended to eat more, resulting in significantly increased growth rates, when compared to control fish. Fish fed krill meal also had a significantly lower condition factor. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to identify pathogenic variants of the ryanodine receptor 2 ( RYR2) gene in a cohort of persons aged 0-40 years who died of sudden unexpected death syndrome (SUD), including a cohort of infants who died of sudden infant death syndrome (SIDS). We genetically screened 29 of the 105 exons of the RYR2 gene associated with catecholaminergic polymorphic ventricular tachycardia (CPVT) in 74 cases of SUD without reported structural abnormalities of the heart. Cases were selected from the case database at the Institute of Forensic Medicine, and subsequent mutational screening by DNA sequencing was performed to detect variants in DNA samples extracted from blood samples of deceased persons. A total of 7 of the examined 74 cases were heterozygous for a rare sequence variant in the RYR2 gene. We identified five novel missense variants (p.Q486H, p.D1872N, p.G2367R, p.E4213D, and p.H4579Y), one synonymous variant (p.L4767L), and one previously reported missense variant (p.G4315E). Follow-up studies were possible in family members of three probands (p.Q486H, p.D1872N, and p.H4579Y), and clinical examinations were conducted in family members of two of these probands (p.Q486H and p.H4579Y). In conclusion, we identified a higher prevalence of variants in the CPVT-associated gene RYR2 than in a previously reported cohort of SIDS (9.4% vs. 1-2%). Segregation studies show that one variant (p.H4579Y) co-segregates with CPVT and is presumed to be pathogenic. [ABSTRACT FROM AUTHOR]

Echinococcus multilocularis is highly endemic in red foxes in southern Belgium (region of Wallonia), especially in the higher located forested areas. The north of Belgium, including the regions of Flanders and Brussels, is more urbanized and has been colonized entirely by red foxes since the 1980s. A temperospatial analysis of compiled epidemiological data from 1996 to 2003 predicted a northwest spread of the cestode from Wallonia and the Netherlands towards Flanders and Brussels ( Prev. Vet. Med. 2006, 76, 137-150). In 2007-2008, none of 187 examined foxes from the north tested positive (<2.8%, α = 0.01), compared to 1.7% in 1996-1999. This suggests that the parasite is not emerging in the examined area and the endemic region has not significantly extended northwest during the last decade. The possible reasons are discussed in the article, including the relatively low altitude, milder climate or low abundance of suitable intermediate hosts. The low prevalence in foxes and the generally low infection rate in humans imply that the risk for public health in Flanders and Brussels is limited anno 2007-2008. [ABSTRACT FROM AUTHOR]

De Cauwer B, Van Den Berge K, Cougnon M, Bulcke R & Reheul D (2010). Weed seedbank responses to 12 years of applications of composts, animal slurries or mineral fertilisers. Weed Research 50, 425–435. Fertiliser amendments can impact weed populations in a variety of ways. This study evaluated the effects of 12-year-long applications of different fertilisation systems on size and composition of the weed seedbank in a conventionally managed maize monoculture field. Fertilisation systems included all factorial combinations of two dairy cattle slurry rates, three vegetable, fruit and garden waste compost rates, and three synthetic N fertiliser rates. Soil samples were taken in each subplot in May 2008 after sowing and prior to herbicide application. Residues recovered from soil samples were tested for weed seedling emergence to characterise soil seedbanks. Total weed seedbank density was affected by mineral N fertilisation, but not by compost or animal slurry application. Weed seedbank composition was related to compost amendment and mineral N fertilisation. Annual compost amendments reduced seedbank density of some persistent species (e.g., Chenopodium album and Solanum nigrum) irrespective of mineral N fertilisation. Compost is a promising tool for incorporation into integrated weed control strategies aimed at reducing weed seedbank persistence. [ABSTRACT FROM AUTHOR]

The LDL receptor (LDLR) plays an essential role in the regulation of plasma (LDL) cholesterol concentrations by virtue of its ability to clear plasma LDL. Down-regulation of the LDLR by proprotein convertase subtilisin/kexin 9 (PCSK9) has recently emerged as a regulatory mechanism that controls plasma LDL cholesterol concentrations. Studies in which PCSK9 is over-expressed in mice, have demonstrated that PCSK9, by enhancing hepatic LDLR degradation, decreases the availability of the LDLR for LDL uptake, resulting in increased plasma LDL cholesterol levels. However, PCSK9 has also recently been shown to mediate down-regulation of surface receptors other than the LDLR, suggesting that it may have much broader roles than initially thought. [ABSTRACT FROM AUTHOR]

Mutations in the KCNQ1, HERG, SCN5A, minK and MiRP1 genes cause long QT syndrome (LQTS), of which there are two forms: the Romano Ward syndrome and the Jervell and Lange-Nielsen syndrome. We have performed DNA sequencing of the LQTS-associated genes in 169 unrelated patients referred for genetic testing with respect to Romano Ward syndrome and in 13 unrelated patients referred for genetic testing with respect to Jervell and Lange-Nielsen syndrome. A total of 37 different mutations in the 5 genes, of which 20 were novel, were identified. Among patients with the most stringent clinical criteria of Romano Ward syndrome, a mutation was identified in 71 %. Twelve of the 13 unrelated patients referred for genetic testing with respect to Jervell and Lange-Nielsen syndrome were provided with a molecular genetic diagnosis. Cascade genetic screening of 505 relatives of index patients with molecularly defined LQTS identified 251 mutation carriers. The observed penetrance was 41 %. Although caution must be exerted, the prevalence of heterozygotes for mutations in the LQTS-associated genes in Norway could be in the range 1/100-1/300, based on the prevalence of patients with Jervell and Lange-Nielsen syndrome. [ABSTRACT FROM AUTHOR]

We have used angle-resolved photoelectron spectroscopy to investigate the occupied antibonding electron states of the Ag(1 1 0)(n×1)O surface along different directions in the surface Brillouin zone. We present experimental evidence that several earlier results obtained along Γ–Y (along the Ag–O chains) contain admixtures from contamination, most probably from carbonate-like contributions. New results are obtained along Γ–X and Γ–S (perpendicular to the chains). These data indicate that the n=2 structure is stabilized by repulsive electronic interaction between neighbouring chains, which diminishes drastically for n=3 and disappears almost completely at n&ges;4. This observation points to a strain field within the substrate which stabilizes the geometry between n=3 (interchain distance 8.7 A˚) and n=8 (23.1 A˚). Its existence is indirectly seen in the n-dependence of the surface phonon energies at Γ, which can be explained quantitatively by umklapp-processes induced by the lateral periodicity of the strain field. We compare our photoemission results for (2 × 1)O with available surface band structure calculations. [Copyright &y& Elsevier]

Using angle-resolved photoemission at ℎω=21.2 eV we have measured the electronic energy band dispersion perpendicular to the Cu–O chains, i.e. along the Γ–X and Y–S directions of the surface Brillouin zone. Our work treats exclusively the occupied antibonding states observed at binding energies between EF and the upper edge of the Cu d-bands. We studied both the fully oxygen-covered surface (0.5 ML coverage) and the striped surface (global coverage <0.5 ML), where alternating Cu(1 1 0) and (2 × 1)O domains form a quasi-1D nanograting. In addition we analyze an umklapp-process of bulk substrate emission. It is induced by the (2 × 1) lattice of the adsorbate and needs to be distinguished from oxygen-derived electronic properties. We compare our results with earlier experimental studies and with available surface band structure calculations. [Copyright &y& Elsevier]

We investigate the inelastic lifetime of electrons in copper at excitation energies Ef between 7 and 20 eV above the Fermi level. High-resolution photoemission experiments allow to determine the inelastic inverse lifetime of final state electrons precisely by measuring the line widths of s,p-band direct transitions. Energy coincidence measurements on Cu(1 0 0) and Cu(1 1 0) show dramatically different line widths which can be quantitatively explained by calculations within the one-step model of photoemission as well as by numerical line shape calculations. Our analysis shows that the distinct line widths on the differently oriented surfaces do not result from lifetime effects but from the influence of the band structure. All observations are in good agreement with a linearly increasing lifetime width Γe=a(Ef−EF), with a=(0.13±0.01) in the energy range mentioned above. [Copyright &y& Elsevier]

We present a high-resolution study of photoemission line widths observed at Ag(1 1 0). A careful data analysis yields k-resolved hole lifetimes τh of d-holes at the X-point of the bulk band structure. At the upper d-band edge we derive τh&ges;22 fs, i.e. more than one order of magnitude larger than predicted for a free-electron gas. In agreement with recent ab initio calculations for d-hole dynamics in Ag we interpret this lifetime enhancement by a small scattering cross-section of d-holes with sp-states below the Fermi level EF. With increasing distance to EF the d-hole lifetimes get rapidly shorter because of the increasing density of d-states and corresponding contributions of intra-d-band scattering processes. [Copyright &y& Elsevier]

Abstract: We report the case of a 59-year-old man with a pheochromocytoma in which erectile dysfunction was the main symptom. Erectile function was related to the amount of noradrenaline secreted by the tumor, as was determined when recurrence of the malignancy was diagnosed twice. Erectile function could be restored by lowering the level of noradrenaline excretion, either by removal of the noradrenaline-producing tumor or by treatment with doxazosin. By stimulating alpha-1-adrenoceptors, high levels of noradrenaline are likely to result in excessive contraction of the corpus cavernosum and penile vessels and, thereby, cause erectile dysfunction. [Copyright &y& Elsevier]

Objective: Missense mutations in the proprotein convertase subtilisin/kexin type 9 (PCSK9) gene have been found to cause autosomal dominant hypercholesterolemia. The objective of this study was to investigate possible mechanisms by which mutation D374Y in the PCSK9 gene causes hypercholesterolemia. Material and Methods: Binding and internalization of low-density lipoprotein LDL in Epstein-Barr virus (EBV)-transformed lymphocytes from D374Y heterozygotes were examined. The autocatalytic activity of the D374Y mutant was studied in transiently transfected HEK293 cells. Results: As determined by Western blot analysis of transiently transfected HEK293 cells, the autocatalytic activity of the D374Y mutant was approximately 95% of the wild-type. Levels of PCSK9 mRNA in EBV-transformed lymphocytes from D374Y heterozygotes and normal controls were similar and less than 1/1000 of the level in HepG2 cells. The amount of cell surface LDL receptors (LDLRs) in EBV-transformed lymphocytes from five D374Y heterozygotes was non-significantly increased by 17% compared with the amount in normal controls. LDLR-dependent binding and internalization of LDL in EBV-transformed lymphocytes from D374Y heterozygotes were non-significantly reduced by 11% and 12%, respectively, compared to the corresponding values in normal controls. Conclusions: LDLR-mediated endocytosis of LDL is not reduced in EBV-transformed lymphocytes from D374Y heterozygotes. Because of the extremely low levels of PCSK9 mRNA in EBV-transformed lymphocytes, it is possible that the LDLR-dependent endocytosis of LDL could be more severely affected in hepatocytes from D374Y heterozygotes than in EBV-transformed lymphocytes. [ABSTRACT FROM AUTHOR]

Abstract: Much data indicates that lowering of plasma triglyceride levels by hypolipidemic agents is caused by a shift in the liver metabolism towards activation of peroxisome proliferator activated receptor (PPAR)α-regulated fatty acid catabolism in mitochondria. Feeding rats with lipid lowering agents leads to hypolipidemia, possibly by increased channeling of fatty acids to mitochondrial fatty acid oxidation at the expense of triglyceride synthesis. Our hypothesis is that increased hepatic fatty acid oxidation and ketogenesis drain fatty acids from blood and extrahepatic tissues and that this contributes significantly to the beneficial effects on fat mass accumulation and improved peripheral insulin sensitivity. To investigate this theory we employ modified fatty acids that change the plasma profile from atherogenic to cardioprotective. One of these novel agents, tetradecylthioacetic acid (TTA), is of particular interest due to its beneficial effects on lipid transport and utilization. These hypolipidemic effects are associated with increased fatty acid oxidation and altered energy state parameters of the liver. Experiments in PPARα-null mice have demonstrated that the effects hypolipidemic of TTA cannot be explained by altered PPARα regulation alone. TTA also activates the other PPARs (e.g., PPARδ) and this might compensate for deficiency of PPARα. Altogether, TTA-mediated clearance of blood triglycerides may result from a lowered level of apo C-III, with a subsequently induction of hepatic lipoprotein lipase activity and (re)uptake of fatty acids from very low density lipoprotein (VLDL). This is associated with an increased hepatic capacity for fatty acid oxidation, causing drainage of fatty acids from the blood stream. This can ultimately be linked to hypolipidemia, anti-adiposity, and improved insulin sensitivity. [Copyright &y& Elsevier]

Examines the effects of a fatty acid analogue, tetradecylthioacetic acid (TTA), on the functional phenotype of native, human acute myeloid leukemia (AML) cells. Healthy individuals receiving oral TTA treatment; Preparation and culture of normal peripheral blood mononuclear cells; Preparation of AML blasts.

Although the phylogeography of European mammals has been extensively investigated since the 1990s, many studies were limited in terms of sampling distribution, the number of molecular markers used and the analytical techniques employed, frequently leading to incomplete postglacial recolonisation scenarios. The broad-scale genetic structure of the European badger (Meles meles) is of interest as it may result from historic restriction to glacial refugia and/or recent anthropogenic impact. However, previous studies were based mostly on samples from western Europe, making it difficult to draw robust conclusions about the location of refugia, patterns of postglacial expansion and recent demography. In the present study, continent-wide sampling and analyses with multiple markers provided evidence for two glacial refugia (Iberia and southeast Europe) that contributed to the genetic variation observed in badgers in Europe today. Approximate Bayesian computation provided support for a colonisation of Scandinavia from both Iberian and southeastern refugia. In the whole of Europe, we observed a decline in genetic diversity with increasing latitude, suggesting that the reduced diversity in the peripheral populations resulted from a postglacial expansion processes. Although MSVAR v.1.3 also provided evidence for recent genetic bottlenecks in some of these peripheral populations, the simulations performed to estimate the method's power to correctly infer the past demography of our empirical populations suggested that the timing and severity of bottlenecks could not be established with certainty. We urge caution against trying to relate demographic declines inferred using MSVAR with particular historic or climatological events. [ABSTRACT FROM AUTHOR]

Objectives. To expand our understanding of the structure and function of proprotein convertase subtilisin/kexin type 9 (PCSK9) by studying how naturally occurring mutations in PCSK9 disrupt the function of PCSK9. Design. Mutations in PCSK9 were identified by sequencing of DNA from subjects with hypo- or hypercholesterolemia. The effect of the identified mutations on the autocatalytic cleavage and secretion of PCSK9, as well as the effect on PCSK9-mediated degradation of the low density lipoprotein receptors, were determined in HepG2 or HEK293 cells transiently transfected with mutant PCSK9-containing plasmids. The findings were collated to the clinical characteristics of the subjects possessing these mutations, and the phenotypic effects were analysed in terms of available structural data for PCSK9. Results. Five novel mutations in PCSK9 were identified. Mutation R215H was a gain-of-function mutation which causes hypercholesterolemia. Mutation G236S and N354I were loss-of-function mutations due to failure to exit the endoplasmic reticulum or failure to undergo autocatalytic cleavage, respectively. Mutations A245T and R272Q were most likely normal genetic variants. By comparing the number of patients with gain-of-function mutations in PCSK9 with the number of familial hypercholesterolemia heterozygotes among subjects with hypercholesterolemia, the prevalence of subjects with gain-of-function mutations in PCSK9 in Norway can be estimated to one in 15 000. Conclusion. This study has provided novel information about the structural requirements for the normal function of PCSK9. However, more studies are needed to determine the mechanisms by which gain-of-function mutations in PCSK9 cause hypercholesterolemia. [ABSTRACT FROM AUTHOR]

During the last century, the European polecat Mustela putorius populations in most of Europe declined and survived in fragmented patches, because of habitat alterations and direct persecution. To assess the genetic consequences of the demographic decline and to describe the spatial pattern of genetic diversity, 250 polecats sampled at seven localities from five European countries – Poland, Denmark (southern Denmark and northern Denmark), Spain, Belgium (eastern and western) and the Netherlands – were screened by means of nine microsatellite loci. Genetic diversity estimated by mean expected heterozygosity ( HE) and allelic richness (AR) were moderately high within populations [range: 0.50 (northern Denmark) ≤ HE≤0.64 (Poland) and 1.33≤AR≤7.80] as compared with other carnivores and mustelids. Bottleneck tests suggested that polecat populations in southern Denmark and Poland have declined recently and populations from northern Denmark and the Netherlands have expanded recently, whereas the remaining populations did not show any sign of demographic change. Recent demographic changes could suggest that some of the populations are still not in equilibrium, which could partly explain the relatively high genetic variability observed in polecat populations despite the drastic decline in population size observed in several European countries. A significant heterozygote deficiency [ FIS=0.19; 0.01≤95% confidence interval (CI)≤0.32] suggests substructuring within the total European sample. Partitioning of the genetic variation among sampling locations ( FST=0.14; 0.06≤95% CI≤0.23) and pairwise FST between localities (range: 0.01≤ FST≤0.37) without any correlation with the geographic distances between localities were found, suggesting a recent divergence and a restriction of gene flow between populations and the action of genetic drift. An assignment test showed that the Polish and the northern Danish populations were the most unique, whereas the other populations were partially admixed. Factorial component analysis tests indicate a subdivision of the total sample into two distinct groups: one including the samples from Poland and the two Danish localities and the second group comprising the remaining localities investigated. The observed pattern of genetic differentiation is suggested to be due to two main routes of recolonization after the last glacial period. To compare the results obtained with microsatellite data, the most variable region of the mitochondrial DNA (d-loop) was sequenced and different phylogenetic reconstructions and genetic diversity analyses based on nucleotide ( π) and haplotype diversity ( h) measures within populations were performed using a subsample of populations. The lack of well-defined geographical structure, as well as the reduced level of mitochondrial DNA variability ( π: 0.00274±0.00038; h: 0.876±0.028) that was found, has been previously reported in several studies on different carnivores and supports the hypothesis of post-glacial recolonization from southern or eastern refugees of Europe as suggested by the microsatellite data. Implications for conservation strategies of the polecat at the European level are discussed. [ABSTRACT FROM AUTHOR]

The first record of the tapeworm Echinococcus multilocularis (Cestoda, Taeniidae) in Red foxes (Vulpes vulpes) in northern Belgium is described. Between 1996 and 1999, 237 dead foxes were examined for the presence of this tapeworm using the intestinal scraping technique. Four foxes (1.7%) were found to be infected with E. multilocularis and showed medium to very high parasitic burdens. Three infected foxes originated from the south of the study area and the fourth animal came from the north of the study area near the border with The Netherlands. These findings are discussed in relation to the high endemicity of E. multilocularis in southern Belgium and to the increased distribution of the Red fox (V. vulpes) in northern Belgium during the last two decades. [Copyright &y& Elsevier]