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31.
Jinte Middeldorp Simone A. van den Berge Eleonora Aronica Dave Speijer Elly M. Hol 《PloS one》2009,4(11)
The human GFAP splice variants GFAPΔ164 and GFAPΔexon6 both result in a GFAP protein isoform with a unique out-of-frame carboxy-terminus that can be detected by the GFAP+1 antibody. We previously reported that GFAP+1 was expressed in astrocytes and in degenerating neurons in Alzheimer''s disease brains. In this study we aimed at further investigating the neuronal GFAP+1 expression and we started by affinity purifying the GFAP+1 antibody. The purified antibody resulted in a loss of neuronal GFAP+1 signal, although other antibodies directed against the amino- and carboxy-terminus of GFAPα still revealed GFAP-immunopositive neurons, as described before. With an in-depth analysis of a western blot, followed by mass spectrometry we discovered that the previously detected neuronal GFAP+1 expression was due to cross-reactivity of the antibody with neurofilament-L (NF-L). This was confirmed by double-label fluorescent immunohistochemistry and western blotting with the unpurified GFAP+1 antibody and an antibody against NF-L. Our data imply that NF-L can accumulate in some tangle-like structures in Alzheimer brains. More importantly, the purified GFAP+1 antibody clearly revealed a specific subtype of astrocytes in the adult human brain. These large astrocytes are present throughout the brain, e.g., along the subventricular zone, in the hippocampus, in the striatum and in the spinal cord of controls, Alzheimer, and Parkinson patients. The presence of a specific GFAP-isoform suggests a specialized function of these astrocytes. 相似文献
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G. Reiner N. Clemens R. Fischer F. Köhler T. Berge S. Hepp H. Willems 《Animal genetics》2009,40(1):57-64
Clinical–chemical traits are diagnostic parameters essential for characterization of health and disease in veterinary practice. The traits show significant variability and are under genetic control, but little is known about the fundamental genetic architecture of this variability, especially in swine. We have identified QTL for alkaline phosphatase (ALP), lactate (LAC), bilirubin (BIL), creatinine (CRE) and ionized sodium (Na+ ), potassium (K+ ) and calcium (Ca++ ) from the serum of 139 F2 pigs from a Meishan/Pietrain family before and after challenge with Sarcocystis miescheriana , a protozoan parasite of muscle. After infection, the pigs passed through three stages representing acute disease, subclinical disease and chronic disease. Forty-two QTL influencing clinical–chemical traits during these different stages were identified on 15 chromosomes. Eleven of the QTL were significant on a genome-wide level; 31 QTL were chromosome-wide significant. QTL showed specific health/disease patterns with respect to the baseline values of the traits as well as the values obtained through the different stages of disease. QTL influencing different traits at different times were found primarily on chromosomes 1, 3, 7 and 14. The most prominent QTL for the investigated clinical–chemical traits mapped to SSC3 and 7. Baseline traits of ALP, LAC, BIL, Ca++ and K+ were influenced by QTL regions on SSC3, 6, 7, 8 and 13. Single QTL explained up to 21.7% of F2 phenotypic variance. Our analysis confirms that variation of clinical–chemical traits is associated with multiple chromosomal regions. 相似文献
35.
Investigation of the antifouling constituents from the brown alga Sargassum muticum (Yendo) Fensholt
Alexandra Bazes Alla Silkina Philippe Douzenel Fabienne Faÿ Nelly Kervarec Danièle Morin Jean-Pascal Berge Nathalie Bourgougnon 《Journal of applied phycology》2009,21(4):395-403
One of the most promising alternatives to toxic heavy metal-based paints is offered by the development of antifouling coatings
in which the active ingredients are compounds naturally occurring in marine organisms and operating as natural antisettlement
agents. Sessile marine macroalgae are remarkably free from settlement by fouling organisms. They produce a wide variety of
chemically active metabolites in their surroundings, potentially as an aid to protect themselves against other settling organisms.
In this study, a dichloromethane extract from the brown seaweed Sargassum muticum was tested in situ and, after 2 months of immersion, showed less fouling organisms on paints in which the extract was included,
compared to paints containing only copper after 2 months of immersion. No barnacles or mussels have been observed on the test
rack. Identification by NMR and GC/MS of the effective compound revealed the abundance of palmitic acid, a commonly found
fatty acid. Pure palmitic acid showed antibacterial activity at 44 μg mL−1, and also inhibited the growth of the diatom Cylindrotheca closterium at low concentration (EC50 = 45.5 μg mL−1), and the germination of Ulva lactuca spores at 3 μg mL−1. No cytotoxicity was highlighted, which is promising in the aim of the development of an environmentally friendly antifouling
paint. 相似文献
36.
Jørgen Berge Paul E. Renaud Ketil Eiane Bjørn Gulliksen Finlo R. Cottier Øystein Varpe Torleiv Brattegard 《Polar Biology》2009,32(7):953-961
Whereas Arctic benthic decapods are not a species-rich group, they can dominate the local epifauna and play important roles
in the ecosystem. We studied the decapod fauna from Isfjorden (Svalbard, Norway, 78°N) by sampling from 22 stations and comparing
with 50 and 100-year-old data from the same localities. Our data provide no evidence of changes in the species composition
of decapods during the last 50 years. Hence, we do not observe the poleward shift of species found in several pelagic communities
in the North Atlantic. However, there is statistical evidence for changes in the community structure between 1908 and both
1958 and 2007. The main change is a shift towards communities more dominated by the spider crab Hyas araneus and the hermit crab Pagurus pubescens in 2007, and with a corresponding decrease in the two shrimp species Lebbeus polaris and Spirontocaris spinus. These shrimps are specialist predators compared to the more opportunistic, scavenging crabs. We argue that increased disturbance
levels may be a causal factor behind the observed community change, with likely sources of disturbance including trawling
and climatic fluctuations. 相似文献
37.
Anders Wittrup Si-He Zhang Gerdy B. ten Dam Toin H. van Kuppevelt Per Bengtson Maria Johansson Johanna Welch Matthias M?rgelin Mattias Belting 《The Journal of biological chemistry》2009,284(47):32959-32967
Cellular uptake of several viruses and polybasic macromolecules requires the expression of cell-surface heparan sulfate proteoglycan (HSPG) through as yet ill defined mechanisms. We unexpectedly found that among several cell-surface-binding single chain variable fragment (scFv) anti-HS antibody (αHS) clones, only one, AO4B08, efficiently translocated macromolecular cargo to intracellular vesicles through induction of HSPG endocytosis. Interestingly, AO4B08-induced PG internalization was strictly dependent on HS 2-O-sulfation and appeared independent of intact N-sulfation. AO4B08 and human immunodeficiency virus (HIV)-Tat, i.e. a well known cell-penetrating peptide, were shown to compete for the internalizing PG population. To obtain a more detailed characterization of this pathway, we have developed a procedure for the isolation of endocytic vesicles by conjugating AO4B08 with superparamagnetic nanoparticles. [35S]sulfate-labeled HSPG was found to accumulate in isolated, AO4B08-containing vesicles, providing the first biochemical evidence for intact HSPG co-internalization with its ligand. Further analysis revealed the existence of both syndecan, i.e. a transmembrane HSPG, and glycosyl-phosphatidyl-inositol-anchored glypican in purified vesicles. Importantly, internalized syndecan and glypican were found to co-localize in AO4B08-containing vesicles. Our data establish HSPGs as true internalizing receptors of macromolecular cargo and indicate that the sorting of cell-surface HSPG to endocytic vesicles is determined by a specific HS epitope that can be carried by both syndecan and glypican core protein. 相似文献
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Gudrun Valdimarsdottir Marie-José Goumans Fumiko Itoh Susumu Itoh Carl-Henrik Heldin Peter ten Dijke 《BMC cell biology》2006,7(1):16-11
Background
In endothelial cells (EC), transforming growth factor-β (TGF-β) can bind to and transduce signals through ALK1 and ALK5. The TGF-β/ALK5 and TGF-β/ALK1 pathways have opposite effects on EC behaviour. Besides differential receptor binding, the duration of TGF-β signaling is an important specificity determinant for signaling responses. TGF-β/ALK1-induced Smad1/5 phosphorylation in ECs occurs transiently. 相似文献40.
Valve replacement in patients with mitral valve regurgitation is indicated when symptoms occur or left ventricular function becomes impaired. Using different surgical techniques, mitral valve reconstruction has lead to earlier interventions with good clinical results. In order to determine the possibility of a mitral valve reconstruction, echocardiographic parameters are necessary. With transoesophageal echocardiography a segmental analysis of the entire mitral valve can be performed; mitral valve motion abnormalities and severity and direction of the regurgitation jet can be judged. From this analysis clues for underlying pathology can be derived as well as the eligibility of a successful mitral valve reconstruction. This article focuses on transoesophageal examination with segmental analysis in patients with mitral valve regurgitation. 相似文献