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991.
992.
Athanasios K. Anagnostopoulos Aggeliki Kolialexi Ariadni Mavrou Konstantinos Vougas Nikos Papantoniou Aris Antsaklis Emmanuel Kanavakis Michael Fountoulakis George Th. Tsangaris 《Journal of Proteomics》2010,73(5):943-950
Klinefelter syndrome is a sex chromosomal abnormality (47, XXY karyotype), occurring approximately in 1 in 1000 male live births. In the present study proteomic analysis was performed in twelve 2nd trimester amniotic fluid samples, eight coming from pregnancies with normal males and four with Klinefelter syndrome foetuses, as shown by routine prenatal cytogenetic analysis. Samples were analysed by 2-DE, coupled with MALDI-TOF-MS analysis. Three proteins (Ceruloplasmin, Alpha-1-antitrypsin and Zinc-alpha-2-glycoprotein) were found to be up-regulated in samples obtained from pregnancies with Klinefelter syndrome foetuses, whereas four proteins (Apolipoprotein A-I, Plasma retinol-binding protein, Gelsolin, and Vitamin D-binding protein) were down regulated when compared to proteins detected in samples from normal foetuses. The differential expression of Ceruloplasmin, Apolipoprotein A-I and Plasma retinol-binding protein was further confirmed by immunoblotting. Since these proteins are likely to cross the placenta barrier and be detected in maternal plasma they could be used as biomarkers for the non-invasive prenatal diagnosis of Klinefelter syndrome. 相似文献
993.
Exposure to stress causes differential neural modifications in various limbic regions, namely the prefrontal cortex, hippocampus and amygdala. We investigated whether α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) phosphorylation is involved with these stress effects. Using an acute inescapable stress protocol with rats, we found opposite effects on AMPA receptor phosphorylation in the medial prefrontal cortex (mPFC) and dorsal hippocampus (DH) compared to the amygdala and ventral hippocampus (VH). After stress, the phosphorylation of Ser831-GluA1 was markedly decreased in the mPFC and DH, whereas the phosphorylation of Ser845-GluA1 was increased in the amygdala and VH. Stress also modulated the GluA2 subunit with a decrease in the phosphorylation of both Tyr876-GluA2 and Ser880-GluA2 residues in the amygdala, and an increase in the phosphorylation of Ser880-GluA2 in the mPFC. These results demonstrate that exposure to acute stress causes subunit-specific and region-specific changes in glutamatergic transmission, which likely lead to the reduced synaptic efficacy in the mPFC and DH and augmented activity in the amygdala and VH. In addition, these findings suggest that modifications of glutamate receptor phosphorylation could mediate the disruptive effects of stress on cognition. They also provide a means to reconcile the contrasting effects that stress has on synaptic plasticity in these regions. Taken together, the results provide support for a brain region-oriented approach to therapeutics. 相似文献
994.
Eva Untersmayr Giovanna Bises Philipp Starkl Charles L. Bevins Otto Scheiner George Boltz-Nitulescu Fritz Wrba Erika Jensen-Jarolim 《PloS one》2010,5(2)
Background
IgE antibodies play a paramount role in the pathogenesis of various intestinal disorders. To gain insights in IgE-mediated pathophysiology of the gut, we investigated the expression of the high affinity IgE receptor FcεRI in human intestinal epithelium.Methodology/Principal Findings
FcεRI α-chain, as detected by immunohistochemistry, was positive in epithelial cells for eight of eleven (8/11) specimens from colon cancer patients and 5/11 patients with inflammation of the enteric mucosa. The FcεRIα positive epithelial cells co-expressed FcεRIγ, whereas with one exception, none of the samples was positive for the β-chain in the epithelial layer. The functionality of FcεRI was confirmed in situ by human IgE binding. In experiments with human intestinal tumor cell lines, subconfluent Caco-2/TC7 and HCT-8 cells were found to express the α- and γ-chains of FcεRI and to bind IgE, whereas confluent cells were negative for γ-chains.Conclusions/Significance
Our data provide the first evidence that the components of a functional FcεRI are in vitro expressed by the human intestinal epithelial cells depending on differentiation and, more importantly, in situ in epithelia of patients with colon cancer or gastrointestinal inflammations. Thus, a contribution of FcεRI either to immunosurveillance or pathophysiology of the intestinal epithelium is suggested. 相似文献995.
Passannante M Marti CO Pfefferli C Moroni PS Kaeser-Pebernard S Puoti A Hunziker P Wicky C Müller F 《PloS one》2010,5(10):e13681
Biochemical purifications from mammalian cells and Xenopus oocytes revealed that vertebrate Mi-2 proteins reside in multisubunit NuRD (Nucleosome Remodeling and Deacetylase) complexes. Since all NuRD subunits are highly conserved in the genomes of C. elegans and Drosophila, it was suggested that NuRD complexes also exist in invertebrates. Recently, a novel dMec complex, composed of dMi-2 and dMEP-1 was identified in Drosophila. The genome of C. elegans encodes two highly homologous Mi-2 orthologues, LET-418 and CHD-3. Here we demonstrate that these proteins define at least three different protein complexes, two distinct NuRD complexes and one MEC complex. The two canonical NuRD complexes share the same core subunits HDA-1/HDAC, LIN-53/RbAp and LIN-40/MTA, but differ in their Mi-2 orthologues LET-418 or CHD-3. LET-418 but not CHD-3, interacts with the Krüppel-like protein MEP-1 in a distinct complex, the MEC complex. Based on microarrays analyses, we propose that MEC constitutes an important LET-418 containing regulatory complex during C. elegans embryonic and early larval development. It is required for the repression of germline potential in somatic cells and acts when blastomeres are still dividing and differentiating. The two NuRD complexes may not be important for the early development, but may act later during postembryonic development. Altogether, our data suggest a considerable complexity in the composition, the developmental function and the tissue-specificity of the different C. elegans Mi-2 complexes. 相似文献
996.
997.
Fritz Höffeler 《当今生物学》2014,44(1):52-60
How humans and their food affect each other There are numerous interactions and dependencies between humans and their food. They are reflected especially in changes in the genetic compositions and in modifications of gene regulations. Four pathways of interaction have been identified so far: The individual gene repertoire of man determines the reactions of his body to the consumed food (nutrigenetics); nutrients are influencing the regulation of a variety of our genes (nutrigenomics); traditional dietary habits can lead to reciprocal genetic changes in humans and their food organisms (coevolutional processes); humans are changing the gene repertorie of almost all of their food organisms by positive selection of desired properties and by negative selections of unwanted properties (breeding and cultivation). 相似文献
998.
A Mutation in VPS35, Encoding a Subunit of the Retromer Complex, Causes Late-Onset Parkinson Disease
Alexander Zimprich Anna Benet-Pagès Walter Struhal Elisabeth Graf Sebastian H. Eck Marc N. Offman Dietrich Haubenberger Sabine Spielberger Eva C. Schulte Peter Lichtner Shaila C. Rossle Norman Klopp Elisabeth Wolf Klaus Seppi Walter Pirker Stefan Presslauer Brit Mollenhauer Regina Katzenschlager Thomas Foki Christoph Hotzy Eva Reinthaler Ashot Harutyunyan Robert Kralovics Annette Peters Fritz Zimprich Thomas Brücke Werner Poewe Eduard Auff Claudia Trenkwalder Burkhard Rost Gerhard Ransmayr Juliane Winkelmann Thomas Meitinger Tim M. Strom 《American journal of human genetics》2011,(1):168-175
To identify rare causal variants in late-onset Parkinson disease (PD), we investigated an Austrian family with 16 affected individuals by exome sequencing. We found a missense mutation, c.1858G>A (p.Asp620Asn), in the VPS35 gene in all seven affected family members who are alive. By screening additional PD cases, we saw the same variant cosegregating with the disease in an autosomal-dominant mode with high but incomplete penetrance in two further families with five and ten affected members, respectively. The mean age of onset in the affected individuals was 53 years. Genotyping showed that the shared haplotype extends across 65 kilobases around VPS35. Screening the entire VPS35 coding sequence in an additional 860 cases and 1014 controls revealed six further nonsynonymous missense variants. Three were only present in cases, two were only present in controls, and one was present in cases and controls. The familial mutation p.Asp620Asn and a further variant, c.1570C>T (p.Arg524Trp), detected in a sporadic PD case were predicted to be damaging by sequence-based and molecular-dynamics analyses. VPS35 is a component of the retromer complex and mediates retrograde transport between endosomes and the trans-Golgi network, and it has recently been found to be involved in Alzheimer disease. 相似文献
999.
Mayi TH Rigamonti E Pattou F Staels B Chinetti-Gbaguidi G 《Biochemical and biophysical research communications》2011,404(1):1195-462
Adipose tissue macrophages (ATM) are the major source of visfatin, a visceral fat adipokine upregulated during obesity. Also known to play a role in B cell differentiation (pre-B cell colony-enhancing factor (PBEF)) and NAD biosynthesis (nicotinamide phosphoribosyl transferase (NAMPT)), visfatin has been suggested to play a role in inflammation.Liver X Receptor (LXR) and Peroxisome Proliferator-Activated Receptor (PPAR)γ are nuclear receptors expressed in macrophages controlling the inflammatory response. Recently, we reported visfatin as a PPARγ target gene in human macrophages. In this study, we examined whether LXR regulates macrophage visfatin expression. Synthetic LXR ligands decreased visfatin gene expression in a LXR-dependent manner in human and murine macrophages. The decrease of visfatin mRNA was paralleled by a decrease of protein secretion. Consequently, a modest and transient decrease of NAD+ concentration was observed. Interestingly, LXR activation decreased the PPARγ-induced visfatin gene and protein secretion in human macrophages.Our results identify visfatin as a gene oppositely regulated by the LXR and PPARγ pathways in human macrophages. 相似文献
1000.
The root anatomy of the subalpine to alpine plant species Saussurea discolor (Willd.) DC., and Saussurea pygmaea (Jacq.) Spreng., (Asteraceae) has been investigated by means of light and fluorescence microscopy on specimens of Austrian
provenance. Both species develop a so called interxylary cork which mediates the splitting of the root into various strands.
This phenomenon takes place in the secondary xylem and involves the development of a periderm separating the originally solid
xylem cylinder. Interxylary cork is currently known from approximately 40 species of the Dicotyledones. This is the first
report of this specific anatomical structure from the two studied species. 相似文献