Showing papers by "Christer Hogstrand published in 2009"
TL;DR: The mechanisms of cellular zinc homeostasis are discussed, and an important role is proposed for the zinc transporter solute carrier family 39, member 7 (SLC39A7; commonly referred to as ZIP7), which releases zinc from the endoplasmic reticulum and might be required for tyrosine kinase activation.
211 citations
TL;DR: It is concluded that the indirect effects of Cu exposure regulate gene expression to a much greater degree than the direct effects.
Abstract: Although copper (Cu) is an essential micronutrient for all organisms, in excess, waterborne Cu poses a significant threat to fish from the cellular to population level. We examined the physiologica...
52 citations
TL;DR: Insight is provided into mechanisms by which MeHg may impair cellular processes in addition to behavioral impairments such as those associated with learning and memory, and the potential utility of an integrated approach incorporating gene expression with behavioral endpoints is highlighted.
49 citations
TL;DR: It is suggested that the preference of trout to use cool water temperatures may supersede behaviors to avoid heavy metals, and trout will avoid dissolved metals at concentrations below those measured in Prickly Pear Creek.
Abstract: A history of hard-rock mining has resulted in elevated concentrations of heavy metals in Prickly Pear Creek (MT, USA). Remediation has improved water quality; however, dissolved zinc and cadmium concentrations still exceed U.S. Environmental Protection Agency water-quality criteria. Physical habitat, salmonid density, fish health, and water quality were assessed, and metal concentrations in fish tissues, biofilm, and macroinvertebrates were determined to evaluate the existing condition in the watershed. Cadmium, zinc, and lead concentrations in fish tissues, biofilm, and invertebrates were significantly greater than those at the upstream reference site and an experimental site farther downstream of the confluence. Fish densities were greatest, and habitat quality for trout was better, downstream of the confluence, where water temperatures were relatively cool (16°C). Measures of fish health (tissue metal residues, histology, metallothionein concentrations, and necropsies), however, indicate that the health of trout at this site was negatively affected. Trout were in colder but more contaminated water and were subjected to increased trace element exposures and associated health effects. Maximum water temperatures in Prickly Pear Creek were significantly lower directly below Spring Creek (16°C) compared to those at an experimental site 10 km downstream (26°C). Trout will avoid dissolved metals at concentrations below those measured in Prickly Pear Creek; however, our results suggest that the preference of trout to use cool water temperatures may supersede behaviors to avoid heavy metals.
16 citations
01 Jan 2009
16 citations
01 Jan 2009
10 citations
01 Jan 2009
TL;DR: In this article, the European Food Safety Authority (EFSA) was asked to deliver a scientific opinion on the safety and efficacy of the product Biosprint ® as a feed additive for sows.
Abstract: SUMMARY Following a request from the European Commission, the European Food Safety Authority (EFSA) was asked to deliver a scientific opinion on the safety and efficacy of the product Biosprint ® (Saccharomyces cerevisiae) as a feed additive for sows. This product is already authorised without a time limit for use in piglets, cattle for fattening and dairy cows. Saccharomyces cerevisiae is considered by EFSA to have QPS status and therefore no assessment of safety for the target species, the consumer and the wider environment is required. The use with sows is considered unlikely to introduce hazards for users of the products not already considered. Consequently, in the present assessment the FEEDAP Panel has considered only the efficacy of the additive Biosprint ® for the target species. Evidence that the additive, when fed to sows over the entire production cycle, is able to produce a significant beneficial effect on the weight of litters and individual piglets was demonstrated in the three studies provided. Therefore, the FEEDAP Panel concludes that the efficacy of Biosprint ® is demonstrated in sows at the minimum recommended dose.
7 citations
01 Jan 2009
TL;DR: The FEEDAP Panel concluded from an acute study in dogs that tachycardia and peripheral vasodilatation observed are in line with the expected pharmacological action and it appeared that the dog could be considered as more sensitive to ractopamine (β-adrenergic substances).
Abstract: SUMMARY Ractopamine hydrochloride is pharmacologically classified as a phenethanolamine βadrenoceptor agonist. The use of the substance as a feed additive is authorised in different countries (USA, Canada, Japan and Mexico) for growth promotion of fattening pigs and cattle. Ractopamine has not been assessed in the EU so far. Following a request from the European Commission, the European Food Safety Authority (EFSA) was asked to provide an opinion on the JECFA evaluation for ractopamine hydrochloride, having consulted and closely co-operated with other organisations such as EMEA and the Community Reference Laboratory responsible for β-agonists (BVL in Berlin). The metabolic fate of ractopamine hydrochloride is similar in the target species (pig and cattle), laboratory animals and humans. The FEEDAP Panel concluded from an acute study in dogs that tachycardia and peripheral vasodilatation observed are in line with the expected pharmacological action. From another acute study in dogs, with limited statistical power, a pharmacological NOAEL of 2 µg kg -1 bw could be derived. Comparing dog and monkey data it appeared that the dog could be considered as more sensitive to ractopamine (β-adrenergic substances). However, the FEEDAP Panel considered that there was not enough data to support this conclusion.
5 citations
01 Jan 2009
4 citations
01 Jan 2009
TL;DR: The FEEDAP Panel considers the data insufficient to finally conclude on the efficacy of Bonvital in chickens for fattening.
Abstract: SUMMARY Following a request from the European Commission, the European Food Safety Authority (EFSA) was asked to deliver a scientific opinion on the safety and efficacy of the product Bonvital used as feed additive for chickens for fattening. The microbial feed additive Bonvital is a preparation of Enterococcus faecium. This product is authorised for use in piglets, pigs for fattening, sows and chickens for fattening (until April 2009). The applicant is now seeking authorisation for use of this product as a zootechnical additive (functional group: gut flora stabilisers) in feed for chickens for fattening at a dose range of 0.5 x 10 9 –2 x 10 9 CFU kg -1 of complete feedingstuff. Data from four studies were provided, only two of which included the minimum recommended dose. Efficacy was demonstrated at a dose of around 0.5 x 10 9 CFU kg -1 feed in two studies. In a field trial with 34500 birds, the effect seen in the Bonvital group could not be used as evidence of efficacy due to the weaknesses of the experimental design. The FEEDAP Panel considers the data insufficient to finally conclude on the efficacy of Bonvital in chickens for fattening. The compatibility of Bonvital has been demonstrated with the coccidiostats robenidine hydrochloride, maduramicin ammonium, diclazuril, decoquinate, halofuginone hydrobromide, monensin sodium and lasalocid A sodium.
4 citations
01 Jan 2009
TL;DR: A preliminary evaluation of the safety and efficacy of paromomycin sulphate when used as feed additive under the category coccidiostats/histomonostats found it shows an antimicrobial effect on susceptible bacterial strains at levels considerably lower than those proposed for feed use.
Abstract: SUMMARY Following a request from the European Commission (Article 15 of Regulation (EC) No 1831/2003), the European Food Safety Authority (EFSA) was asked to deliver a preliminary evaluation of the safety and efficacy of paromomycin sulphate when used as feed additive under the category coccidiostats/histomonostats. HistoBloc ® contains 8 % paromomycin sulphate, an aminoglycoside antibiotic, produced by fermentation of Streptomyces chrestomyceticus. It is applied to prevent histomoniasis in turkeys for fattening and turkeys reared for breeding at concentrations between 100 and 400 mg kg -1 complete feed. The safety for the target animal of paromomycin sulphate from histoBloc ® at the highest proposed dose (400 mg kg -1 diet) could not be established due to the absence of data. Paromomycin sulphate shows an antimicrobial effect on susceptible bacterial strains at levels considerably lower than those proposed for feed use. Even at the lowest proposed feed concentration (100 mg kg -1 diet), it selects for resistance and cross-resistances at high frequency against a variety of other aminoglycosides among intestinal bacteria. As aminoglycoside antibiotics are used in human and veterinary medicine, serious consequences
TL;DR: Protein extraction and two-dimensional SDS-polyacrylamide gel electrophoresis of the protein extracts in bacteria exposed to very high concentrations of AgNO3 revealed a general reduction in the number of expressed proteins, although two protein spots were conspicuously over expressed in the exposed bacteria compared to control.
01 Jan 2009