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1.
Wild Iceland scallops Chlamys islandica from an Icelandic bay were examined for parasites. Queen scallops Aequipecten opercularis from the Faroe Islands and king scallops Pecten maximus and queen scallops from Scottish waters were also examined. Observations revealed heavy infections of eimeriorine parasites in 95–100% of C. islandica but not the other scallop species. All life stages in the apicomplexan reproduction phases, i.e. merogony, gametogony and sporogony, were present. Trophozoites and meronts were common within endothelial cells of the heart’s auricle and two generations of free merozoites were frequently seen in great numbers in the haemolymph. Gamonts at various developmental stages were also abundant, most frequently free in the haemolymph. Macrogamonts were much more numerous than microgamonts. Oocysts were exclusively in the haemolymph; live mature oocysts contained numerous (>500) densely packed pairs of sporozoites forming sporocysts.Analysis of the 18S ribosomal DNA revealed that the parasite from C. islandica is most similar (97.7% identity) to an unidentified apicomplexan isolated from the haemolymph of the giant clam, Tridacna crocea, from Japan. Phylogenetic analyses showed that the novel sequence consistently grouped with the Tridacna sequence which formed a robust sister clade to the rhytidocystid group.We propose the name Margolisiella islandica sp. nov., referring to both type host and type locality.  相似文献   
2.
Several novel thiol-reactive clenbuterol analogues were coupled in high yield with bovine serum albumin (BSA). After labelling of unreacted cysteines with maleimide spin label (MiSL), the yield of the coupling reaction was determined by electron paramagnetic resonance (EPR) spectroscopy and spectral analysis. Two spin-probe populations with different mobility states were quantitatively determined. Molecular dynamics was used to model the structure of clenbuterol analogues and spin label conjugated to BSA and recognition of conjugates by anti-clenbuterol antibodies was demonstrated. The recognition of BSA-A, BSA-C and BSA-S conjugates with monoclonal and polyclonal anti-clenbuterol (mCLB-Ab and rCLB-Ab) antibodies was an indication, that chlorine substituents on the aromatic ring of clenbuterol derivatives are not necessary for the binding of antibodies to the conjugates. These results confirmed the importance of the tert-butylamino group as a part of the epitope and contribute to the understanding of the recognition process with anti-clenbuterol antibodies.  相似文献   
3.

Background  

Liquid chromatography coupled to mass spectrometry (LC/MS) has been widely used in proteomics and metabolomics research. In this context, the technology has been increasingly used for differential profiling, i.e. broad screening of biomolecular components across multiple samples in order to elucidate the observed phenotypes and discover biomarkers. One of the major challenges in this domain remains development of better solutions for processing of LC/MS data.  相似文献   
4.

Background

While beneficial health effects of fish and fish oil consumption are well documented, the incorporation of n-3 polyunsaturated fatty acids in plasma lipid classes is not completely understood. The aim of this study was to investigate the effect of fish oil supplementation on the plasma lipidomic profile in healthy subjects.

Methodology/Principal Findings

In a double-blinded randomized controlled parallel-group study, healthy subjects received capsules containing either 8 g/d of fish oil (FO) (1.6 g/d EPA+DHA) (n = 16) or 8 g/d of high oleic sunflower oil (HOSO) (n = 17) for seven weeks. During the first three weeks of intervention, the subjects completed a fully controlled diet period. BMI and total serum triglycerides, total-, LDL- and HDL-cholesterol were unchanged during the intervention period. Lipidomic analyses were performed using Ultra Performance Liquid Chromatography (UPLC) coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (QTOFMS), where 568 lipids were detected and 260 identified. Both t-tests and Multi-Block Partial Least Square Regression (MBPLSR) analysis were performed for analysing differences between the intervention groups. The intervention groups were well separated by the lipidomic data after three weeks of intervention. Several lipid classes such as phosphatidylcholine, phosphatidylethanolamine, lysophosphatidylcholine, sphingomyelin, phosphatidylserine, phosphatidylglycerol, and triglycerides contributed strongly to this separation. Twenty-three lipids were significantly decreased (FDR<0.05) in the FO group after three weeks compared with the HOSO group, whereas fifty-one were increased including selected phospholipids and triglycerides of long-chain polyunsaturated fatty acids. After seven weeks of intervention the two intervention groups showed similar grouping.

Conclusions/Significance

In healthy subjects, fish oil supplementation alters lipid metabolism and increases the proportion of phospholipids and triglycerides containing long-chain polyunsaturated fatty acids. Whether the beneficial effects of fish oil supplementation may be explained by a remodeling of the plasma lipids into phospholipids and triglycerides of long-chain polyunsaturated fatty acids needs to be further investigated.

Trial Registration

ClinicalTrials.gov NCT01034423  相似文献   
5.
Progression to type 1 diabetes is characterized by complex interactions of environmental, metabolic and immune system factors, involving both degenerative pathways leading to loss of pancreatic β-cells as well as protective pathways. The interplay between the degenerative and protective pathways may hold the key to disease outcomes, but no models have so far captured the two together. Here we propose a mathematical framework, an ordinary differential equation (ODE) model, which integrates metabolism and the immune system in early stages of disease process. We hypothesize that depending on the degree of regulation, autoimmunity may also play a protective role in the initial response to stressors. We assume that β-cell destruction follows two paths of loss: degenerative and autoimmune-induced loss. The two paths are mutually competing, leading to termination of the degenerative loss and further to elimination of the stress signal and the autoimmune response, and ultimately stopping the β-cell loss. The model describes well our observations from clinical and non-clinical studies and allows exploration of how the rate of β-cell loss depends on the amplitude and duration of autoimmune response.  相似文献   
6.
    
Homopolysaccharide (glucan and fructan) synthesis from sucrose by sucrase enzymes in lactic acid bacteria (LAB) has been well studied in the genera Leuconostoc, Streptococcus and Lactobacillus . This study aimed to identify and characterize genes encoding glucansucrase/glucosyltransferase (GTF) and fructansucrases/fructosyltransferase (FTF) enzymes from genomic DNA of 'rare' Indonesian exopolysaccharide-producing LAB. From a total of 63 exopolysaccharide-producing LAB isolates obtained from foods, beverages and environmental samples, 18 isolates showing the most slimy and mucoid colony morphologies on sucrose were chosen for further study. By comparing bacterial growth on De Man, Rogosa and Sharpe (MRS)-sucrose with that on MRS-raffinose, and using the results of a previous PCR screening study with degenerate primer pairs targeting the conserved catalytic domain of GTFs, various strains were identified as producers of fructan (13), of glucan only (five) or as potential producers of both glucan and fructan (nine). Here, we report the characteristics of three gtf genes and one ftf gene obtained from Weissella confusa strains MBF8-1 and MBF8-2. Strain MBF8-1 harbored two putative gtf genes with high sequence similarity to GTFB of Lactobacillus reuteri 121 and GTF180 of L. reuteri 180, respectively. Strain MBF8-2 possessed single gtf and ftf genes with high sequence similarity to GTFKg3 of Lactobacillus fermentum Kg3 and DSRWC of Weissella cibaria , and FTF levansucrase of L. reuteri 121, respectively.  相似文献   
7.
  总被引:1,自引:0,他引:1  
A novel clustering approach named Clustering Objects on Subsets of Attributes (COSA) has been proposed (Friedman and Meulman, (2004). Clustering objects on subsets of attributes. J. R. Statist. Soc. B 66, 1–25.) for unsupervised analysis of complex data sets. We demonstrate its usefulness in medical systems biology studies. Examples of metabolomics analyses are described as well as the unsupervised clustering based on the study of disease pathology and intervention effects in rats and humans. In comparison to principal components analysis and hierarchical clustering based on Euclidean distance, COSA shows an enhanced capability to trace partial similarities in groups of objects enabling a new discovery approach in systems biology as well as offering a unique approach to reveal common denominators of complex multi-factorial diseases in animal and human studies. Doris Damian, Matej Orešič, and Elwin Verheij contributed equally to this work.  相似文献   
8.
Recent clinical evidence suggests important role of lipid and amino acid metabolism in early pre-autoimmune stages of type 1 diabetes pathogenesis. We study the molecular paths associated with the incidence of insulitis and type 1 diabetes in the Non-Obese Diabetic (NOD) mouse model using available gene expression data from the pancreatic tissue from young pre-diabetic mice. We apply a graph-theoretic approach by using a modified color coding algorithm to detect optimal molecular paths associated with specific phenotypes in an integrated biological network encompassing heterogeneous interaction data types. In agreement with our recent clinical findings, we identified a path downregulated in early insulitis involving dihydroxyacetone phosphate acyltransferase (DHAPAT), a key regulator of ether phospholipid synthesis. The pathway involving serine/threonine-protein phosphatase (PP2A), an upstream regulator of lipid metabolism and insulin secretion, was found upregulated in early insulitis. Our findings provide further evidence for an important role of lipid metabolism in early stages of type 1 diabetes pathogenesis, as well as suggest that such dysregulation of lipids and related increased oxidative stress can be tracked to beta cells.  相似文献   
9.
10.
The morphometric analyses and genetic variability assessed by RAPD markers have been used to analyse relations among six Serapias taxa from Croatia (S. istriaca, S. pulae originally described as hybrid, S. ionica, S. vomeracea, S. lingua and S. cordigera). S. istriaca distributed in southern Istria and the island of Lošinj and S. pulae stenoendemic taxon distributed only in southern Istria S. ionica is endemic to the Ionian and Dalmatian islands, while the remaining taxa are more widely distributed. The obtained results shows that the endemic S. istriaca is a well characterised taxon, that S. pulae is a hybrid between S. istriaca and S. lingua and that the hybrid is morphologically and genetically more similar to S. lingua than the second parental species S. istriaca. The division into the subsections Steno-, Medio- and Platypetalae is founded based on the floral morphology while the division into the sections Serapias and Bilamellaria is not evident in the quantitative morphological and genetic analyses. Furthermore, considerable genetic resemblance between S. vomeracea and S. ionica was established.  相似文献   
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