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111.
112.
Maintaining pH and blood gases in a narrow range is essential to sustain normal biochemical reactions. Decreased oxygenation, poor tissue perfusion, disturbance to CO2 expiration, and shortage of HCO3 − can lead to metabolic acidosis. This is a common situation in swine, and originates from a broad range of medical conditions. pH and blood gases appear to be under genetic control, and populations with physiological traits closer to the pathological thresholds may be more susceptible to developing pathological conditions. However, little is known about the genetic basis of such traits. We have therefore estimated phenotypic and genetic variability and identified quantitative trait loci (QTL) for pH and blood gases in blood samples from 139 F2 pigs from the Meishan/Pietrain family. Samples were taken before and after challenge with Sarcocystis miescheriana , a protozoan parasite of muscle. Twenty-seven QTL influencing pH and blood gases were identified on nine chromosomes. Five of the QTL were significant on a genome-wide level; 22 QTL were significant on a chromosome-wide level. QTL for pH-associated traits have been mapped to SSC3, 18 and X. QTL associated with CO2 have been detected on SSC6, 7, 8 and 9, and QTL associated with O2 on SSC2 and SSC8. QTL showed specific health/disease patterns that were related to the physiological state of the pigs from day 0, to acute disease (day 14), convalescence (day 28) and chronic disease (day 42). The results demonstrate that pH and blood gases are influenced by multiple chromosomal areas, each with relatively small effects. 相似文献
113.
We analyzed the molecular forms of acetylcholinesterase (AChE) in the nematode Steinernema carpocapsae. Two major AChEs are involved in acetylcholine hydrolysis. The first class of AChE is highly sensitive to eserine (IC50 = 0.05 microM). The corresponding molecular forms are: an amphiphilic 14S form converted into a hydrophilic 14.5S form by mild proteolysis and two hydrophilic 12S and 7S forms. Reduction of the amphiphilic 14S form with 10 mM dithiothreitol produces hydrophilic 7S and 4S forms, indicating that it is an oligomer of hydrophilic catalytic subunits linked by disulfide bond(s) to a hydrophobic structural element that confers the amphiphilicity to the complex. Sedimentation coefficients suggest that 4S, 7S, 12S forms correspond to hydrophilic monomer, dimer, tetramer and that the 14S form is also a tetramer linked to one structural element. The second class of AChE is less sensitive to eserine (IC50 = 0.1 mM). Corresponding molecular forms are hydrophilic and amphiphilic 4S forms (monomers) and a major amphiphilic 7S form converted into a hydrophilic dimer by Bacillus thuringiensis phosphatidylinositol-specific phospholipase C. This amphiphilic 7S form thus possesses a glycolipid anchor. It appears that Steinernema (a very primitive invertebrate) presents AChEs with two types of membrane association that closely resemble those described for amphiphilic G2 and G4 forms of AChE in more evolved animals. 相似文献
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Sigve Nakken Morten Johansen Julien Fillebeen Ole Petter Berge Harald Kirker?d Tor-Kristian Jenssen Eivind Hovig 《Bioinformation》2012,8(22):1119-1122
Experimental models of human tissues and disease phenotypes frequently rely upon immortalized cell lines, which are easily
accessible and simple to use due to their infinite capability of cell division. For decades, cell lines have been used to investigate
cellular mechanisms of disease and the efficacy of drugs, most prominently for human cancers. However, the large body of
knowledge with respect to human cell lines exists primarily in an unstructured fashion, that is, as free text in the scientific
literature. Here we present CellLineMiner, a novel text mining-based web database that provides a comprehensive view of human
cell line knowledge. The application offers a simple search in all indexed cell lines, accompanied by a rapid display of all identified
literature associations. The CellLineMiner is intended to serve as a knowledge resource companion to the cellular model systems
used in biomedical research.
Availability
CellLineMiner is accessible at http://dev.pubgene.com/cellmine 相似文献119.
Paul E. Renaud Jørgen Berge Øystein Varpe Ole Jørgen Lønne Jasmine Nahrgang Camilla Ottesen Ingeborg Hallanger 《Polar Biology》2012,35(3):401-412
During a recent period of increased influx of warm Atlantic water to the western coast of Svalbard, we have observed a northward
expansion of boreal Atlantic cod (Gadus morhua) and haddock (Melanogrammus aeglefinus) into areas dominated by the native polar cod (Boreogadus saida). To determine the potential impact of new ecological interactions, we studied the diet of co-occurring juvenile gadoids
in fjords, open water, and sea ice around Svalbard. We also reviewed the available literature on polar cod feeding in different
habitats across the Arctic to determine whether region, habitat, or fish size may influence diet. Feeding by polar cod in
the pelagic zone was size dependent, with small fish primarily consuming Calanus spp. and smaller copepods, with an increasing ration of Themisto spp. at larger sizes. In benthic habitats, diets were more varied and included considerably more unidentified material and
sediment. Less than 40% dietary overlap was detected among the three species when they were found together. Stable isotope
analyses indicated these patterns were representative of longer-term assimilation. The low interspecific dietary overlap suggests
little direct competition. Future increases in abundance and the high predation potential of the boreal taxa, however, may
impact the persistence of polar cod on some Arctic shelves. 相似文献
120.
Therese H. Røst Line L. Haugan Moi Kjetil Berge Bart Staels Gunnar Mellgren Rolf K. Berge 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2009,1791(11):1076-1083
Tetradecylthioacetic acid (TTA) is a hypolipidemic modified fatty acid and a peroxisome proliferator-activated receptor (PPAR) ligand. The mechanisms of TTA-mediated effects seem to involve the PPARs, but the effects have not been assigned to any specific PPAR subtype. PPARα−/− mice were employed to study the role of PPARα after TTA treatment. We also performed in vitro transfection assays to obtain mechanistic knowledge of how TTA affected PPAR activation in the presence of PPARγ coactivator (PGC)-1 and steroid receptor coactivators (SRC)-1 and SRC-2, which are associated with energy balance and mitochondrial biogenesis. We show that TTA increases hepatic fatty acid β-oxidation in PPARα−/− mice. TTA acts as a pan-PPAR ligand in vitro, and PGC-1, SRC-1 and SRC-2 have cell type and PPAR-specific effects together with TTA. In the absence of exogenous ligands, SRC-1 did not induce PPAR activity, while PGC-1 was the most potent PPAR coactivator. When the coactivators were overexpressed, pronounced effects of TTA were observed especially for PPARδ and PPARγ. We conclude that PPARα is involved in, but not required for, the hypolipidemic mechanisms of TTA. It appears that the activity of PPARδ, with substantial contribution of nuclear receptor coactivators, PGC-1 in special, is conducive to TTA's mechanism of action. 相似文献