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191.
Dr. Ursula Sonnewald Linda R. White Elin Ødegård Niels Westergaard Inger J. Bakken Jan Aasly Geirmund Unsgård Arne Schousboe 《Neurochemical research》1996,21(9):987-993
[U-13C]Glutamate metabolism was studied in primary brain cell cultures. Cell extracts as well as redissolved lyophilized media
were subjected to nuclear magnetic resonance spectroscopy in order to identify13C labeled metabolites. Both neurons and astrocytes metabolized glutamate extensively with13C label appearing in aspartate in all cultures. Additionally, GABA is synthesized in the GABAergic cortical neurons. Labeling
of lactate and glutamine was prominent in medium from astrocytes, but not detectable in cerebral cortical neurons. Cerebellar
granule neurons showed some labeling of lactate. Glutamate derived from the first turn of the tricarboxylic acid cycle (1,2,3-13C3-isotopomer) is present in all cell types analyzed. However, glutamate derived from the second turn of the cycle was only
detected in granule neurons. In astrocytes, the transaminase inhibitor aminooxyacetic acid not only abolished the appearance
of aspartate, but also of the 1,2,3-13C3-isotopomer of glutamate, thus showing that transmination is necessary for the conversion of 2-oxoglutarate to glutamate.
The entry of glutamate into the tricarboxylic acid cycle was, however, not seriously impaired. 3-nitropropionic acid abolished
the appearance of aspartate, the 1,2,3-13C3-isotopomer of glutamate and lactate in cerebellar granule neurons.
Special issue dedicated to Dr. Herman Bachelard. 相似文献
192.
Øystein Bruserud Laila Mentzoni Brynjar Foss Jann Bergheim Sigbjørn Berentsen Ingerid Nesthus 《Cancer immunology, immunotherapy : CII》1997,43(5):275-282
Normal peripheral blood mononuclear cells (PBMC responders) were cultured together with non-irradiated allogeneic PBMC (more
than 95% leukaemia blasts) derived from patients with acute leukaemia (referred to as leukaemic PBMC stimulators). Cytokine
secretion was determined as cytokine concentrations in supernatants. Both normal PBMC and enriched CD4+ and CD8+ T cells responded to allostimulation with interferon (IFNγ) secretion. Interleukin-1 (IL-1) receptor antagonist and IL-2-neutralizing
antibodies decreased IFNγ secretion. Exogenous IL-1β, IL-2 and IL-7 increased allostimulated IFNγ secretion, whereas decreased
levels were seen in the presence of IL-6, IL-10 and granulocyte-colony-stimulating factor (G-CSF). During allorecognition
IFNγ -neutralizing antibodies decreased acute myelogenous leukaemia (AML) blast secretion of G-CSF. We conclude that (i) both
CD4+ and CD8+ T cells show allostimulated cytokine secretion in response to allogeneic stimulator cells containing a dominating population
of native, cytokine-secreting leukaemia blasts, and (ii) IFNγ released during this response can modulate the function of allogeneic
AML blasts.
Received: 4 June 1996 / Accepted: 15 October 1996 相似文献
193.
T lymphocyte secretion of interleukin-13 (IL-13) in response to different activation signals was characterized in vitro. IL-13
release was investigated when virus transformed B lymphocytes or acute myelogenous leukaemia (AML) blasts were used as accessory
cells during T cell activation. First, a majority of both CD4+ and CD8+ TCRαβ+ T lymphocyte clones, derived from normal individuals and bone marrow transplant recipients, secreted IL-13 in response to
a standardized mitogenic activation signal (phytohaemagglutinin+IL-2+ B lymphocyte accessory cells). The CD4+ cells showed significantly higher IL-13 levels than the CD8+ subsets. Second, when leukaemic accessory cells (more than 95% AML blasts) were used during T cell activation, IL-13 was
released both during alloactivation of normal T lymphocytes and during mitogen activation of posttransplant T cells. Third,
when normal T lymphocytes were stimulated with allogeneic AML blasts, addition of IL-13-neutralizing monoclonal antibodies
decreased interferon γ levels. Although addition of IL-13-neutralizing antibodies did not alter granulocyte-colony-stimulating
factor secretion by allostimulating AML blasts, altered blast proliferation was detected for certain patients. Thus, most
T cell clones can release IL-13, and IL-13 can modulate cytokine responses during T cell recognition of allogeneic AML cells.
Received: 24 April 1997 / Accepted: 24 July 1997 相似文献
194.
Reikvam Håkon Hatfield Kimberley Bruserud Øystein 《Metabolomics : Official journal of the Metabolomic Society》2016,12(1):1-11
Metabolomics - Allogeneic stem cell transplantation is used in the treatment of younger patients with severe hematological diseases, especially hematological malignancies, and acute graft versus... 相似文献
195.
R. Fernández M. Schubert A. M. Vargas‐Velázquez A. Brownlow G. A. Víkingsson U. Siebert L. F. Jensen N. Øien D. Wall E. Rogan B. Mikkelsen W. Dabin A. H. Alfarhan S. A. Alquraishi K. A. S. Al‐Rasheid G. Guillot L. Orlando 《Molecular ecology resources》2016,16(1):266-276
The field of population genetics is rapidly moving into population genomics as the quantity of data generated by high‐throughput sequencing platforms increases. In this study, we used restriction‐site‐associated DNA sequencing (RADSeq) to recover genomewide genotypes from 70 white‐beaked (Lagenorhynchus albirostris) and 43 Atlantic white‐sided dolphins (L. acutus) gathered throughout their north‐east Atlantic distribution range. Both species are at a high risk of being negatively affected by climate change. Here, we provide a resource of 38 240 RAD‐tags and 52 981 nuclear SNPs shared between both species. We have estimated overall higher levels of nucleotide diversity in white‐sided (π = 0.0492 ± 0.0006%) than in white‐beaked dolphins (π = 0.0300 ± 0.0004%). White‐sided dolphins sampled in the Faroe Islands, belonging to two pods (N = 7 and N = 11), showed similar levels of diversity (π = 0.0317 ± 0.0007% and 0.0267 ± 0.0006%, respectively) compared to unrelated individuals of the same species sampled elsewhere (e.g. π = 0.0285 ± 0.0007% for 11 Scottish individuals). No evidence of higher levels of kinship within pods can be derived from our analyses. When identifying the most likely number of genetic clusters among our sample set, we obtained an estimate of two to four clusters, corresponding to both species and possibly, two further clusters within each species. A higher diversity and lower population structuring was encountered in white‐sided dolphins from the north‐east Atlantic, in line with their preference for pelagic waters, as opposed to white‐beaked dolphins that have a more patchy distribution, mainly across continental shelves. 相似文献
196.
Anna B. Mazzarella Sanne Boessenkool Kjartan Østbye Leif Asbjørn Vøllestad Emiliano Trucchi 《Ecology and evolution》2016,6(10):3161-3173
Understanding the genetic basis of traits involved in adaptive divergence and speciation is one of the most fundamental objectives in evolutionary biology. Toward that end, we look for signatures of extreme plate loss in the genome of freshwater threespine sticklebacks (Gasterosteus aculeatus). Plateless stickleback have been found in only a few lakes and streams across the world; they represent the far extreme of a phenotypic continuum (plate number) that has been studied for years, although plateless individuals have not yet been the subject of much investigation. We use a dense single nucleotide polymorphism dataset made using RADseq to study fish from three freshwater populations containing plateless and low plated individuals, as well as fish from full plated marine populations. Analyses were performed using FastStructure, sliding windows FST, Bayescan and latent factor mixed models to search for genomic differences between the low plated and plateless phenotypes both within and among the three lakes. At least 18 genomic regions which may contribute to within‐morph plate number variation were detected in our low plated stickleback populations. We see no evidence of a selective sweep between low and plateless fish; rather reduction of plate number within the low plated morph seems to be polygenic. 相似文献
197.
L. Fugger N. Morling L. P. Ryder N. Ødum J. Georgsen A. Svejgaard 《Immunogenetics》1989,30(3):208-213
DP gene typing using in vitro DNA amplification combined with sequence-specific oligonucleotide probes has recently been reported.
The resulting DNA amplification was specific for theHLA-DPB locus. Typing for the individualDPB alleles was exclusively dependent on the hybridizations of the probes but hampered by close sequence homology between differentDP alleles yielding complex patterns of reactivity with a panel of probes. We report the combined use of allele-specific DNA
in vitro amplification and allele-specific oligonucleotides in typing forDPB1
*
03 andDPB1
*
06. Complete concordance with PLT typing was observed for theDPB1
*
03 alleles, while in the DPB1*06 group, at least three variantDPB1
*
06 alleles were identified which have not been described previously. 相似文献
198.
Berdal Bjørn P. Olsvik Ørjan Alrnlid Torbjørn Larsen Hans Jørgen Lorentzen-Styr Anne-Marie 《Acta veterinaria Scandinavica》1983,24(1):65-73
Toxoplasma gondii IgG antibodies were measured in 212 goat sera, comparing the Sabin-Feldman dye-test and a three-layer sandwich enzyme-linked immunosorbent assay (ELISA). With 98 % concordance obtained between these 2 tests, the results are at the same paragon as for human sera. Accordingly, the ELISA sandwich procedure appears to be suitable for large-scale analysis of goat sera. The discordant 2 % were ELISA positive and dye-test negative. One possible explanation of the divergent titres is given using an immunized goat model. 相似文献
199.
Rat livers were fixed by perfusion with glutaraldehyde via the portal vein and postfixed with a mixture of osmium tetroxide and potassium ferricyanide. Subsurface cisterns and vesicles were demonstrated, and, from serial sections, it appears that these organelles are part of large, fenestrated cisterns situated parallel to and at a distance of 20-40 nm from the lateral plasma membrane. Some of the cisterns possessed ribosomes on the surface facing the interior of the cell and, at points, they were continuous with the endoplasmic reticulum. From the lateral cisterns, tubules approached the plasma membrane facing the space of Disse and the sinusoid. A network of tubules was found in the vicinity of the bile canaliculus; a part of it lay close to the canalicular plasma membrane. Serial sectioning revealed that this network was continuous with the lateral cisterns via the endoplasmic reticulum. This morphology resembles that of tubulo-cisternal endoplasmic reticulum of such transporting epithelia as the choroid plexus and the renal proximal tubules. 相似文献
200.
The membrane systems of the cardiac muscle cell of Munida tenuimana G. O. Sars are described. The sarcolemma invaginates at the Z level, forming tubules. Narrow tubules branch off in a longitudinal direction from these transverse and radially arranged tubules, forming a narrow transverse collar at the H level where dyadic and triadic junctions are formed with the sarcoplasmic reticulum. 相似文献