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991.
Buddenbrockia plumatellae is an active, muscular, worm-shapedparasite of freshwater bryozoans. This rare and enigmatic animalhas been assigned to the Myxozoa on the basis of 18S ribosomalDNA sequences and the presence of malacosporean spores. Herewe report cloning of four homologous protein-coding genes fromBuddenbrockia worms, the putatively conspecific sac-shaped parasiteoriginally described as Tetracapsula bryozoides and the relatedsac-shaped parasite Tetracapsuloides bryosalmonae, the causativeagent of proliferative kidney disease in salmonid fish. Analysesare consistent with the hypothesis that Buddenbrockia is indeeda malacosporean myxozoan, but do not provide support for conspecificitywith either T. bryozoides or T. bryosalmonae. Implications forthe evolution of worm-like body plans in the Myxozoa are discussed.  相似文献   
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Spinal cord injury (SCI) results in paralysis below the injury and strategies are being developed that support axonal regrowth, yet recovery lags, in part, because many axons are not remyelinated. Herein, we investigated strategies to increase myelination of regenerating axons by overexpression of platelet-derived growth factor (PDGF)-AA and noggin either alone or in combination in a mouse SCI model. Noggin and PDGF-AA have been identified as factors that enhance recruitment and differentiation of endogenous progenitors to promote myelination. Lentivirus encoding for these factors was delivered from a multichannel bridge, which we have previously shown creates a permissive environment and supports robust axonal growth through channels. The combination of noggin+PDGF enhanced total myelination of regenerating axons relative to either factor alone, and importantly, enhanced functional recovery relative to the control condition. The increase in myelination was consistent with an increase in oligodendrocyte-derived myelin, which was also associated with a greater density of cells of an oligodendroglial lineage relative to each factor individually and control conditions. These results suggest enhanced myelination of regenerating axons by noggin+PDGF that act on oligodendrocyte-lineage cells post-SCI, which ultimately led to improved functional outcomes.  相似文献   
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2-[(2H(9))Butoxy]acetic acid and 2-(3-methylbutoxy)acetic acid were synthesized, mixed with 2-butoxyacetic acid, and separated by capillary gas chromatography on a fused-silica column with a length of 50 m, inside diameter of 0.200 mm, and a "free fatty acid phase" wall coating of 0.3 microm film. 2-[(2H(9))Butoxy]acetic acid, 2-butoxyacetic acid, and 2-(3-methylbutoxy)acetic acid were baseline resolved at retention times of 13.55, 13.78, and 15.20 min; 2-(3-methylbutoxy)acetic acid having a peak efficiency of 360,000. Mass spectrometric detection using selected ion monitoring at m/z 66, 57, and 71 showed linear analytical responses from 0.04 ng to at least 200 ng with a limit of detection of 0.04 ng for 2-butoxyacetic acid.  相似文献   
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