Increasing digesta viscosity may increase parasite establishment in the small intestine of sheep

Strongyle infections and diarrhoea are major problems for the sheep industry, but the nutritional factors determining faecal consistency and susceptibility to enteric diseases are not well understood. Soluble non-starch polysaccharides (sNSP) have been shown to affect the physico-chemical environment of the gut lumen, by increasing viscosity of digesta and affecting microbial fermentation in the large intestine; however, the role of sNSP in sheep has not been studied. sNSP have been shown to increase parasite establishment in the small intestine of mice (3) and decrease parasite establishment in the large intestine of pigs (2). Carboxymethylcellulose (CMC) is a non-fermentable viscous-forming agent that is used to study the effect of soluble NSP in increasing digesta viscosity independent of potential effects on fermentation (I). The aims of this study were to investigate whether increasing viscosity of digesta using CMC may affect establishment of Trichostrongylus colubriformis and Telodorsagio (Ostenagia) circumcincta in sheep and whether the type of roughage and CMC may affect faecal consistency in sheep with strongyle infections

Increasing viscosity of digesta has detrimental effects on faecal consistency in sheep

Although diarrhoea and faecal soiling of fleece are major problems for the sheep meat and wool industries, there is little information on the nutritional factors that determine faecal consistency in sheep. Research in monogastric species has shown that the soluble non-starch polysaccharide (sNSP) content of the diet is a major determinant of faecal consistency and susceptibility of animals to enteric diseases (2, 3), but there have been no studies on the role of sNSP in sheep. sNSP have profound effects on the physio-chemical conditions of the gut lumen by increasing viscosity of digesta and affecting microbial fermentation in the large intestine (2). Carboxymethylcellulose (CMC) is a non-fermentable viscous-forming agent that has been used in pig diets to study the effect of sNSP of increasing digesta viscosity, independently of potential effects on fermentation (2). This study aimed to investigate if CMC could be used as a model for studying the effect of increasing digesta viscosity in sheep and whether dietary CMC supplementation would have any detrimental effects on faecal consistency

Similarity searching in databases of three-dimensional molecules and macromolecules

This paper discusses algorithmic techniques for measuring the degree of similarity between pairs of threedimensional (3-D) chemical molecules represented by interatomic distance matrices. A comparison of four methods for the calculation of 3-D structural similarity suggests that the most effective one is a procedure that identifies pairs of atoms, one from each of the molecules that are being compared, that lie at the center of geometrically-related volumes of 3-D space. This atom mapping method enables the calculation of a wide range of types of intermolecular similarity coefficient, including measures that are based on physicochemical data. Massively-parallel implementations of the method are discussed, using the AMT Distributed Array Processor, that achieve a substantial increase in performance when compared with a sequential implementation on a UNIX workstation. Current work involves the use of angular information and the extension of the method to field-based similarity searching. Similarity searching in 3-D macromolecules is effected by the use of a maximal common subgraph (MCS) isomorphism algorithm with a novel, graph-based representation of the tertiary structures of proteins. This algorithm is being used to identify similarities between the 3-D structures of proteins in the Brookhaven Protein Data Bank; its use is exemplified by searches involving the NAD-binding fold motif

Temperature and salinity effects on strontium incorporation in otoliths of larval spot (Leiostomus xanthurus)

Author Posting. © National Research Council Canada, 2004. This article is posted here by permission of National Research Council Canada for personal use, not for redistribution. The definitive version was published in Canadian Journal of Fisheries and Aquatic Sciences 61 (2004): 34-42, doi:10.1139/F03-143.Temperature dependence of strontium/calcium (Sr/Ca) ratios in foraminiferal calcite and coral aragonite is well established; however, factors controlling Sr/Ca ratios in fish otoliths remain obscure. To assess temperature dependence of Sr/Ca in marine fish otoliths, we reared spot (Leiostomus xanthurus) larvae under controlled temperature (17–26 °C) and salinity (15‰ and 25‰). We found a significant linear relationship between temperature and Sr/Ca ratios, with a sensitivity of approximately 5%·°C–1. Otolith Sr/Ca values were also significantly higher at a salinity of 25‰ vs. 15‰, after accounting for differences in dissolved Sr/Ca ratios in the ambient water, with a sensitivity of approximately 1%/salinity (‰). These observations complicate the use of Sr/Ca ratios to determine temperature histories of spot larvae, because accurate temperature reconstructions are possible only with a priori knowledge of both ambient salinity and dissolved Sr/Ca ratios. Fully marine species residing in oceanic waters will not experience significant salinity variations; therefore, otolith Sr/Ca ratios may be useful recorders of temperature exposure. Otolith Sr/Ca thermometry in coastal fish species that make regular excursions into estuarine waters will be more problematic. Multiple geochemical tracers, including oxygen stable isotopes and other trace elements, may be necessary to accurately reconstruct temperature and salinity histories in these species.This research was supported by grants from the National Science Foundation to S.R.T. (OCE-0134998) and to S.R.T. and C.M.J. (OCE-9876565), a grant in aid to G.B.M. from the International Women’s Fishing Association, and a PEO International Women’s Organization Scholar Award to G.B.M

Regulation and governance of multinational drug trials in stroke : Barriers and possibilities

Over the last 10 years, there has been stagnation in the number of multinational drug trials in stroke in Europe. One important cause of this is probably the increased burden of laws and regulations that came with the European Union Clinical Trials Directive. The main objective of research regulation and governance should be to protect research participants, their tissues, and data, but the approval systems are complex, regulation is variably interpreted and enforced, and the assessment of studies is often not proportionate to the risk of the research to participants. Such unnecessary barriers should be reduced by simplifying, centralizing, and harmonizing the application process, and by applying regulatory and governance requirements in a way that is proportionate to the potential harms to the patients. The traditional functions of a regulator (in setting, monitoring, and enforcing quality standards) could also be supplemented with an aim to actively help researchers achieve these standards, for example, by giving advice, and ultimately with an aim to facilitate and promote research, for example, by integrating research in everyday clinical practice. Research networks offer one way of integrating research and clinical practice across multiple centers, and can streamline research delivery by supporting researchers deal professionally and efficiently with the regulations and governance requirements. © 2015 World Stroke Organization

Regulation and governance of multinational drug trials in stroke : Barriers and possibilities

Over the last 10 years, there has been stagnation in the number of multinational drug trials in stroke in Europe. One important cause of this is probably the increased burden of laws and regulations that came with the European Union Clinical Trials Directive. The main objective of research regulation and governance should be to protect research participants, their tissues, and data, but the approval systems are complex, regulation is variably interpreted and enforced, and the assessment of studies is often not proportionate to the risk of the research to participants. Such unnecessary barriers should be reduced by simplifying, centralizing, and harmonizing the application process, and by applying regulatory and governance requirements in a way that is proportionate to the potential harms to the patients. The traditional functions of a regulator (in setting, monitoring, and enforcing quality standards) could also be supplemented with an aim to actively help researchers achieve these standards, for example, by giving advice, and ultimately with an aim to facilitate and promote research, for example, by integrating research in everyday clinical practice. Research networks offer one way of integrating research and clinical practice across multiple centers, and can streamline research delivery by supporting researchers deal professionally and efficiently with the regulations and governance requirements. © 2015 World Stroke Organization