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Anne Berit Samuelsen Berit Smestad Paulsen Jens Kristian Wold Svein H. Knutsen Haruki Yamada 《Carbohydrate polymers》1998,35(3-4):145-153
PMIa is a Type II arabinogalactan with anti-complementary activity isolated from the leaves of Plantago major L. It has a molecular weight of 77000–80000 Da and consists of arabinose (38%), galactose (49%), rhamnose (6%), galacturonic acid (7%) and 1.5% protein with hydroxyproline, alanine and serine as the main amino acids. Characterization of PMIa by methylation and GC-MS, methanolysis and GC, Smith degradation, weak acid hydrolysis, 13C-NMR, 1H-NMR, two-dimensional heteronuclear NMR and DEPT show that it consists of 1,3-linked galactan chains with 1,6-linked galactan side chains attached to position 6. The side chains are further branched in position 3 with 1,3-linked galactose residues which have 1,6-linked galactose attached to position 6; these 1,3- and 1,6-linked galactose chains altogether probably form a network. Terminal and 1,5-linked arabinose in furanose form are attached to the galactan mainly through position 3 of the 1,6-linked galactose side chains. 相似文献
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Per-Olof Eriksson Emil Aaltonen Rodrigo Petoral Jr Petter Lauritzson Hideki Miyazaki Kristian Pietras Sven M?nsson Lennart Hansson Peter Leander Oskar Axelsson 《PloS one》2014,9(10)
The current study was carried out to test the potential of a new nanomaterial (Spago Pix) as a macromolecular magnetic MR contrast agent for tumor detection and to verify the presence of nanomaterial in tumor tissue. Spago Pix, synthesized by Spago Nanomedical AB, is a nanomaterial with a globular shape, an average hydrodynamic diameter of 5 nm, and a relaxivity (r1) of approximately 30 (mM Mn)−1 s−1 (60 MHz). The material consists of an organophosphosilane hydrogel with strongly chelated manganese (II) ions and a covalently attached PEG surface layer. In vivo MRI of the MMTV-PyMT breast cancer model was performed on a 3 T clinical scanner. Tissues were thereafter analyzed for manganese and silicon content using inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The presence of nanomaterial in tumor and muscle tissue was assessed using an anti-PEG monoclonal antibody. MR imaging of tumor-bearing mice (n = 7) showed a contrast enhancement factor of 1.8 (tumor versus muscle) at 30 minutes post-administration. Contrast was retained and further increased 2–4 hours after administration. ICP-AES and immunohistochemistry confirmed selective accumulation of nanomaterial in tumor tissue. A blood pharmacokinetics analysis showed that the concentration of Spago Pix gradually decreased over the first hour, which was in good agreement with the time frame in which the accumulation in tumor occurred. In summary, we demonstrate that Spago Pix selectively enhances MR tumor contrast in a clinically relevant animal model. Based on the generally higher vascular leakiness in malignant compared to benign tissue lesions, Spago Pix has the potential to significantly improve cancer diagnosis and characterization by MRI. 相似文献
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Gene expression of myogenic factors and phenotype-specific markers in electrically stimulated muscle of paraplegics. 总被引:2,自引:0,他引:2
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Characterization of Emetic Bacillus weihenstephanensis, a New Cereulide-Producing Bacterium 下载免费PDF全文
Line Thorsen Bjarne Munk Hansen Kristian Fog Nielsen Niels Bohse Hendriksen Richard Kerry Phipps Birgitte Bjrn Budde 《Applied microbiology》2006,72(7):5118-5121
Cereulide production has until now been restricted to the species Bacillus cereus. Here we report on two psychrotolerant Bacillus weihenstephanensis strains, MC67 and MC118, that produce cereulide. The strains are atypical with regard to pheno- and genotypic characteristics normally used for identification of emetic B. cereus strains. MC67 and MC118 produced cereulide at temperatures of as low as 8°C. 相似文献
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Lymphocytes use the integrin leukocyte function‐associated antigen‐1 (LFA‐1) to cross the vasculature into lymph nodes (LNs), but it has been uncertain whether their migration within LN is also LFA‐1 dependent. We show that LFA‐1 mediates prolonged LN residence as LFA‐1?/? CD4 T cells have significantly decreased dwell times compared with LFA‐1+/+ T cells, a distinction lost in hosts lacking the major LFA‐1 ligand ICAM‐1. Intra‐vital two‐photon microscopy revealed that LFA‐1+/+ and LFA‐1?/? T cells reacted differently when probing the ICAM‐1‐expressing lymphatic network. While LFA‐1+/+ T cells returned to the LN parenchyma with greater frequency, LFA‐1?/? T cells egressed promptly. This difference in exit behaviour was a feature of egress through all assessed lymphatic exit sites. We show that use of LFA‐1 as an adhesion receptor amplifies the number of T cells returning to the LN parenchyma that can lead to increased effectiveness of T‐cell response to antigen. Thus, we identify a novel function for LFA‐1 in guiding T cells at the critical point of LN egress when they either exit or return into the LN for further interactions. 相似文献