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排序方式: 共有893条查询结果,搜索用时 46 毫秒
1.
Nathan D. Mathewson Orr Ashenberg Itay Tirosh Simon Gritsch Elizabeth M. Perez Sascha Marx Livnat Jerby-Arnon Rony Chanoch-Myers Toshiro Hara Alyssa R. Richman Yoshinaga Ito Jason Pyrdol Mirco Friedrich Kathrin Schumann Michael J. Poitras Prafulla C. Gokhale L. Nicolas Gonzalez Castro Marni E. Shore Kai W. Wucherpfennig 《Cell》2021,184(5):1281-1298.e26
2.
Ugur Sahin Sylvia Kraft-Bauer Sascha Ohnesorge M. Pfreundschuh Christoph Renner 《Cancer immunology, immunotherapy : CII》1996,42(1):9-14
The combination of CD16/CD30 bispecific monoclonal antibodies (bi-mAb) and unstimulated human resting natural killer (NK)
cells can cure about 50% of mice with severe combined immunodeficiency (SCID) bearing subcutaneously growing established Hodgkin’s
lymphoma. As interleukin-2 (IL-2) and IL-12 have been shown to increase NK cell activity, we tested the capacity of these
cytokines to increase bi-mAb-mediated NK cell cytotoxicity against two types of human tumors (Hodgkin’s disease and colorectal
carcinoma). Unstimulated NK cells needed a three- to five-times higher antibody concentration than cytokine-stimulated NK
cells to exert similar levels of bi-mAb-mediated cytotoxicity. The augmented tumor cell lysis was achieved with IL-12 at considerably
lower concentrations than with IL-2 and was associated with a significantly increased bi-mAb-mediated intracellular Ca2+ mobilization. The efficiency of IL-12 in this setting together with its low toxicity make it the ideal candidate for a combination
therapy with NK-cell-activating bi-mAb in human tumors that are resistant to standard treatment.
Received: 26 July 1995 / Accepted: 16 November 1995 相似文献
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5.
Janine Walter Sascha Hausmann Thomas Drepper Michael Puls Thorsten Eggert Marcel Dihn�� 《PloS one》2012,7(9)
Usage of the enhanced green fluorescent protein (eGFP) in living mammalian cells is limited to aerobic conditions due to requirement of oxygen during chromophore formation. Since many diseases or disease models are associated with acute or chronic hypoxia, eGFP-labeling of structures of interest in experimental studies might be unreliable leading to biased results. Thus, a chromophore yielding a stable fluorescence under hypoxic conditions is desirable. The fluorescence of flavin mononucleotide (FMN)-based fluorescent proteins (FbFPs) does not require molecular oxygen. Recently, the advantages of FbFPs for several bacterial strains and yeasts were described, specifically, their usage as a real time fluorescence marker in bacterial expression studies and their ability of chromophore formation under anaerobic conditions. Our objective was to verify if FbFPs also function in mammalian cells in order to potentially broaden the repertoire of chromophores with ones that can reliably be used in mammalian studies under hypoxic conditions. In the present study, we demonstrate for the first time, that FbFPs can be expressed in different mammalian cells, among them murine neural stem cells during proliferative and differentiated stages. Fluorescence intensities were comparable to eGFP. In contrast to eGFP, the FbFP fluorescence did not decrease when cells were exposed to defined hypoxic conditions neither in proliferating nor in differentiated cells. Thus, FbFPs can be regarded as an alternative to eGFP in studies that target cellular structures which are exposed to hypoxic conditions. 相似文献
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8.
Spatio-temporal mapping of local soil pH changes induced by roots of lupin and soft-rush 总被引:1,自引:0,他引:1
Nicole Rudolph Sebastian Voss Ahmad B. Moradi Stefan Nagl Sascha E. Oswald 《Plant and Soil》2013,369(1-2):669-680
Aims
The rhizosphere is a dynamic system strongly influenced by root activity. Roots modify the pH of their surrounding soil causing the soil pH to vary as a function of distance from root surface, location along root axes, and root maturity. Non-invasive imaging techniques provide the possibility to capture pH patterns around the roots as they develop.Methods
We developed a novel fluorescence imaging set up and applied to the root system of two lupin (Lupinus albus L., Lupinus angustifolius L.) and one soft-rush (Juncus effusus L.) species. We grew plants in glass containers filled with soil and equipped with fluorescence sensor foils on the container side walls. We gained highly-resolved data on the spatial distribution of H+ around the roots by taking time-lapse images of the samples over the course of several days.Results
We showed how the soil pH in the vicinity of roots developed over time to different values from that of the original bulk soil. The soil pH in the immediate vicinity of the root surface varied greatly along the root length, with the most acidic point being at 0.56–3.36 mm behind the root tip. Indications were also found for temporal soil pH changes due to root maturity.Conclusion
In conclusion, this study shows that this novel optical fluorescence imaging set up is a powerful tool for studying pH developments around roots in situ. 相似文献9.
Sascha Naomi McKeon Marta Moreno Maria Anise Sallum Marinete Marins Povoa Jan Evelyn Conn 《Memórias do Instituto Oswaldo Cruz》2013,108(5):605-615
To evaluate whether environmental heterogeneity contributes to the
genetic heterogeneity in Anopheles triannulatus, larval habitat
characteristics across the Brazilian states of Roraima and Pará and genetic
sequences were examined. A comparison with Anopheles goeldii
was utilised to determine whether high genetic diversity was unique to
An. triannulatus. Student t test and
analysis of variance found no differences in habitat characteristics between the
species. Analysis of population structure of An. triannulatus
and An. goeldii revealed distinct demographic histories in a
largely overlapping geographic range. Cytochrome oxidase I
sequence parsimony networks found geographic clustering for both species;
however nuclear marker networks depicted An. triannulatus with
a more complex history of fragmentation, secondary contact and recent
divergence. Evidence of Pleistocene expansions suggests both species are more
likely to be genetically structured by geographic and ecological barriers than
demography. We hypothesise that niche partitioning is a driving force for
diversity, particularly in An. triannulatus. 相似文献
10.
Kornelia Neveling Lilian?A. Martinez-Carrera Irmgard H?lker Angelien Heister Aad Verrips Seyyed?Mohsen Hosseini-Barkooie Christian Gilissen Sascha Vermeer Maartje Pennings Rowdy Meijer Margot te?Riele Catharina?J.M. Frijns Oksana Suchowersky Linda MacLaren Sabine Rudnik-Sch?neborn Richard?J. Sinke Klaus Zerres R.?Brian Lowry Henny?H. Lemmink Lutz Garbes Joris?A. Veltman Helenius?J. Schelhaas Hans Scheffer Brunhilde Wirth 《American journal of human genetics》2013,92(6):946-954
Spinal muscular atrophy (SMA) is a heterogeneous group of neuromuscular disorders caused by degeneration of lower motor neurons. Although functional loss of SMN1 is associated with autosomal-recessive childhood SMA, the genetic cause for most families affected by dominantly inherited SMA is unknown. Here, we identified pathogenic variants in bicaudal D homolog 2 (Drosophila) (BICD2) in three families afflicted with autosomal-dominant SMA. Affected individuals displayed congenital slowly progressive muscle weakness mainly of the lower limbs and congenital contractures. In a large Dutch family, linkage analysis identified a 9q22.3 locus in which exome sequencing uncovered c.320C>T (p.Ser107Leu) in BICD2. Sequencing of 23 additional families affected by dominant SMA led to the identification of pathogenic variants in one family from Canada (c.2108C>T [p.Thr703Met]) and one from the Netherlands (c.563A>C [p.Asn188Thr]). BICD2 is a golgin and motor-adaptor protein involved in Golgi dynamics and vesicular and mRNA transport. Transient transfection of HeLa cells with all three mutant BICD2 cDNAs caused massive Golgi fragmentation. This observation was even more prominent in primary fibroblasts from an individual harboring c.2108C>T (p.Thr703Met) (affecting the C-terminal coiled-coil domain) and slightly less evident in individuals with c.563A>C (p.Asn188Thr) (affecting the N-terminal coiled-coil domain). Furthermore, BICD2 levels were reduced in affected individuals and trapped within the fragmented Golgi. Previous studies have shown that Drosophila mutant BicD causes reduced larvae locomotion by impaired clathrin-mediated synaptic endocytosis in neuromuscular junctions. These data emphasize the relevance of BICD2 in synaptic-vesicle recycling and support the conclusion that BICD2 mutations cause congenital slowly progressive dominant SMA. 相似文献