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11.
Böhme H Rudloff E Schöne F Schumann W Hüther L Flachowsky G 《Archives of animal nutrition》2007,61(4):308-316
The nutritive value of genetically modified myristic acid-rich rapeseed, in which a acyl-thioesterase gene inserted, was studied. Crude nutrients, amino acid and fatty acid profiles as well as mineral and glucosinolate contents were determined and compared with those of the non-transgenic parental cultivar. The concentration of crude nutrients, minerals and amino acids were found to be within the range of natural variance. The myristic and palmitic acid content increased from 0.1 - 11.4% and from 3.6-20%, respectively, at the expense of oleic acid, which decreased from 68.6-42.6% of total fatty acids. The glucosinolate contents increased from 12.4 micromol/g in the parental plant to 19 micromol/g DM in the GM-plant. Full-fat rapeseed of both cultivars was incorporated in pig diets at a level of 15%, and the digestibility and the production efficiency were tested under ad libitum feeding conditions with ten pigs each over the growing finishing period from 32-105 kg BW. The experimental diets did not show significant differences in digestibility and energetic feeding value. However, feed intake and weight gain decreased presumably due to the increasing glucosinolate intake associated with the feeding of transgenic rapeseed. The dietary fatty acids profile influenced the fatty acid profile of body fat. Myristic acid accumulated in back fat and intramuscular fat while the oleic acid content decreased. The increased glucosinolate intake affected the weight of thyroid glands and their iodine concentration. 相似文献
12.
The CNS of bilateral symmetric organisms is characterized by intensive contralateral axonal connections. Genetic screens in Drosophila have identified only a few genes required for guiding commissural growth cones toward and across the midline. Two evolutionarily conserved signaling molecules, Netrin and Slit, are expressed in the CNS midline cells. Netrin acts primarily as an attractive signaling cue, whereas Slit mediates repulsive functions. Here, we describe a detailed analysis of the Drosophila gene schizo, which is required for commissure formation. schizo leads to a commissural phenotype reminiscent of netrin mutant embryos. Double-mutant analyses indicate that Netrin and Schizo act independently. The schizo mutant phenotype can be suppressed by either expressing netrin in the CNS midline cells or by a reduction of the slit gene dose, indicating that the balance of attractive and repulsive signaling is impaired in schizo mutants. Overexpression of the schizo RNA in the CNS midline using the GAL4/UAS system leads to a slit phenocopy, suggesting that schizo primarily antagonizes Slit signaling. This is further supported by cell type-specific rescue experiments. The schizo gene generates at least two proteins containing a conserved Sec7 and a pleckstrin homology domain (PH) characteristic for guanine nucleotide exchange factors (GEF) acting on ARF GTPases, which are known to regulate endocytosis. In support of the notion that schizo regulates Slit expression via endocytosis, we found that block of endocytosis leads to a schizo-like phenotype. We thus propose that the balance of the two signaling cues Netrin and Slit can be regulated, controlling membrane dynamics. 相似文献
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14.
Toneff T Mende-Mueller L Wu Y Hwang SR Bundey R Thompson LM Chesselet MF Hook V 《Journal of neurochemistry》2002,82(1):84-92
Proteolytic fragments of huntingtin (htt) in human lymphoblast cell lines from HD and control cases were compared to those in human HD striatal and cortical brain regions, by western blots with epitope-specific antibodies. HD lymphoblast cell lines were heterozygous and homozygous for the expanded CAG triplet repeat mutations, which represented adult onset and juvenile HD. Lymphoblasts contained NH(2)- and COOH-terminal htt fragments of 20-100 kDa, with many similar htt fragments in HD compared to control lymphoblast cell lines. Detection of htt fragments in a homozygous HD lymphoblast cell line demonstrated proteolysis of mutant htt. It was of interest that adult HD lymphoblasts showed a 63-64 kDa htt fragment detected by the NH(2)-domain antibody, which was not found in controls. In addition, control and HD heterozygous cells showed a common 60-61 kDa band (detected by the NH(2)-domain antibody), which was absent in homozygous HD lymphoblast cells. These results suggest that the 63-64 kDa and 60-61 kDa NH(2)-domain htt fragments may be associated with mutant and normal htt, respectively. In juvenile HD lymphoblasts, the presence of a 66-kDa, instead of the 63-64 kDa N-domain htt fragment, may be consistent with the larger polyglutamine expansion of mutant htt in the juvenile case of HD. Lymphoblasts and striatal or cortical regions from HD brains showed similarities and differences in NH(2)- and COOH-terminal htt fragments. HD striatum showed elevated levels of 50 and 45 kDa NH(2)-terminal htt fragments [detected with anti(1-17) serum] compared to controls. Cortex from HD and control brains showed similar NH(2)-terminal htt fragments of 50, 43, 40, and 20 kDa; lymphoblasts also showed NH(2)-terminal htt fragments of 50, 43, 40, and 20 kDa. In addition, a 48-kDa COOH-terminal htt band was elevated in HD striatum, which was also detected in lymphoblasts. Overall, results demonstrate that mutant and normal htt undergo extensive proteolysis in lymphoblast cell lines, with similarities and differences compared to htt fragments observed in HD striatal and cortical brain regions. These data for in vivo proteolysis of htt are consistent with the observed neurotoxicity of recombinant NH(2)-terminal mutant htt fragments expressed in transgenic mice and in transfected cell lines that may be related to the pathogenesis of HD. 相似文献
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16.
Paul LD Maurer HH 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,789(1):43-57
Eschscholtzia californica preparations are in use as phytopharmaceuticals and as herbal drugs. Studies are described on the metabolism and the toxicological analysis of the Eschscholtzia californica alkaloids californine and protopine in rat urine using gas chromatography-mass spectrometry. The identified metabolites indicated that californine is extensively metabolized by N-demethylation and/or single or double demethylenation with consecutive catechol-O-methylation of one of the hydroxy groups. Protopine, however, only undergoes extensive demethylenation of the 2,3-methylenedioxy group followed by catechol-O-methylation. All phenolic hydroxy metabolites were found to be partly conjugated. The authors' systematic toxicological analysis procedure using full-scan gas chromatography-mass spectrometry after acid hydrolysis, liquid-liquid extraction and microwave-assisted acetylation allowed the detection of the main metabolites of californine and protopine in rat urine after a dose which should correspond to that of drug users. Therefore, use of Eschscholtzia californica preparations should also be detectable in human urine by the authors' systematic toxicological analysis procedure. 相似文献
17.
dos Santos Fagundes I Rotta LN Schweigert ID Valle SC de Oliveira KR Huth Krüger A Souza KB Souza DO Perr ML 《Neurochemical research》2001,26(3):245-249
We have investigated the glycine, serine and leucine metabolism in slices of various rat brain regions of 14-day-old or adult rats, using [1-14C]glycine, [2-14C]glycine, L-[3-14C]serine and L-[U-14C]leucine. We showed that the [1-14C]glycine oxidation to CO2 in all regions studied occurs almost exclusively through its cleavage system (GCS) in brains of both 14-day-old and adults rats. In 14-day-old rats, the highest oxidation of [1-14C]glycine was in cerebellum and the lowest in medulla oblongata. In these animals, the L-[U-14C]leucine oxidation was lower than the [1-14C]glycine oxidation, except in medulla oblongata where both oxidations were the same. Serine was the amino acid that showed lowest oxidation to CO2 in all structure studied. In adult rats brains, the highest oxidation of [1-14C]glycine was in cerebral cortex and the lowest in medulla oblongata. We have not seen difference in the lipid synthesis from both glycine labeled, neither in 14-day-old rats nor in adult ones, indicating that the lipids formed from glycine were not neutral. Lipid synthesis from serine was significantly high than lipid synthesis and from all other amino acids studied in all studied structures. Protein synthesis from L-[U-14C]leucine was significantly higher than that from glycine in all regions and ages studied. 相似文献
18.
Liane Correia-Costa Ana Cristina Santos Milton Severo António Guerra Franz Schaefer Alberto Caldas Afonso Henrique Barros Ana Azevedo 《PloS one》2015,10(6)
Objective
To evaluate the association between obesity indices and blood pressure (BP) at 4 years of age, in each sex, and to quantify to which extent this association is mediated by inflammation and insulin resistance (IR).Materials and Methods
We studied 1250 4-year-old children selected from the population-based birth cohort Generation XXI. Associations between body mass index (BMI) z-score and waist-to-height ratio (WHtR), office BP, inflammation (high sensitivity C-reactive protein) and IR (HOMA-IR index) were assessed. Path Analysis, a modified multivariate regression approach, was applied to test causal models and quantify direct and indirect effects of predictors of systolic (SBP) and diastolic BP (DBP).Results
SBP and DBP increased significantly with BMI and WHtR in both sexes. There was a strong direct association (explaining 74.1-93.2% of the total association) of both measures of adiposity with SBP, in both sexes. This association was additionally indirectly mediated by IR, particularly regarding WHtR (20.5% in girls and 9.4% in boys). Mediation by inflammation did not reach statistical significance in either sex. Regarding DBP, the direct effect of adiposity was strong (>95% for BMI and WHtR in boys) and the mediation by IR was much smaller in boys than in girls.Discussion
The direct association between adiposity and BP in healthy 4-year-old children is strong and IR plays an important mediating role. The strength of effects of IR and inflammation suggests sex differences in the complex interplay between BP, adiposity and inflammation. 相似文献19.
Juan L. Torres-Pérez Liane S. Guild Roy A. Armstrong Jorge Corredor Anabella Zuluaga-Montero Ramón Polanco 《PloS one》2015,10(11)
Reef corals typically contain a number of pigments, mostly due to their symbiotic relationship with photosynthetic dinoflagellates. These pigments usually vary in presence and concentration and influence the spectral characteristics of corals. We studied the variations in pigment composition among seven Caribbean shallow-water Scleractinian corals by means of High Performance Liquid Chromatography (HPLC) analysis to further resolve the discrimination of corals. We found a total of 27 different pigments among the coral species, including some alteration products of the main pigments. Additionally, pigments typically found in endolithic algae were also identified. A Principal Components Analysis and a Hierarchical Cluster Analysis showed the separation of coral species based on pigment composition. All the corals were collected under the same physical environmental conditions. This suggests that pigment in the coral’s symbionts might be more genetically-determined than influenced by prevailing physical conditions of the reef. We further investigated the use of remote sensing reflectance (Rrs) as a tool for estimating the total pigment concentration of reef corals. Depending on the coral species, the Rrs and the total symbiont pigment concentration per coral tissue area correlation showed 79.5–98.5% confidence levels demonstrating its use as a non-invasive robust technique to estimate pigment concentration in studies of coral reef biodiversity and health. 相似文献
20.
Anita Kloss-Brandst?tter Hansi Weissensteiner Gertraud Erhart Georg Sch?fer Lukas Forer Sebastian Sch?nherr Dominic Pacher Christof Seifarth Andrea St?ckl Liane Fendt Irma Sottsas Helmut Klocker Christian W. Huck Michael Rasse Florian Kronenberg Frank R. Kloss 《PloS one》2015,10(8)