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Rat organic solute carrier protein 1 (rOscp1) was isolated from a rat testis cDNA library. Isolated rOscp1 cDNA consisted of 1089 base pairs that encoded a 363-amino acid protein, and the amino acid sequence was 88% and 93% identical to that of human OSCP1 (hOSCP1) and mouse Oscp1 (mOscp1), respectively. The message for rOscp1 is highly detected in rat testis. When expressed in X. oocytes, rOscp1 mediated the high affinity transport of p-aminohippurate (PAH) with a Km value of 15.7+/-1.9 microM, and rOscp1-mediated organic solutes were exhibited in time- and Na+-independent manners. rOscp1 also transported various structurally heterogenous compounds such as testosterone, dehydroepiandrosterone sulfate (DHEA-S), and taurocholate with some differences in substrate specificity compared with hOSCP1. Immunohistochemical analysis revealed that the rOscp1 protein is localized in the basal membrane side of Sertoli cells as observed in mouse testis [Kobayashi et al., 2007; Kobayashi, Y., Tsuchiya, A., Hayashi, T., Kohyama, N., Ohbayashi, M., Yamamoto, T., 2007. Isolation and characterization of polyspecific mouse organic solute carrier protein 1 (mOscp1). Drug Metabolism and Disposition 35 (7), 1239-1245]. Thus, the present results indicate that a newly isolated cDNA clone, rOscp1, is a polyspecific organic solute carrier protein with some differences in substrate specificity compared with human and mouse OSCP1.  相似文献   
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Elastic fibers play the principal roles in providing elasticity and integrity to various types of human organs, such as the arteries, lung, and skin. However, the molecular mechanism of elastic fiber assembly that leads to deposition and crosslinking of elastin along microfibrils remains largely unknown. We have previously shown that developing arteries and neural crest EGF-like protein (DANCE) (also designated fibulin-5) is essential for elastogenesis by studying DANCE-deficient mice. Here, we report the identification of latent transforming growth factor-beta-binding protein 2 (LTBP-2), an elastic fiber-associating protein whose function in elastogenesis is not clear, as a DANCE-binding protein. Elastogenesis assays using human skin fibroblasts reveal that fibrillar deposition of DANCE and elastin is largely dependent on fibrillin-1 microfibrils. However, downregulation of LTBP-2 induces fibrillin-1-independent fibrillar deposition of DANCE and elastin. Moreover, recombinant LTBP-2 promotes deposition of DANCE onto fibrillin-1 microfibrils. These results suggest a novel regulatory mechanism of elastic fiber assembly in which LTBP-2 regulates targeting of DANCE on suitable microfibrils to form elastic fibers.  相似文献   
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Viral vector systems are efficient for transfection of foreign genes into many tissues. Especially, retrovirus based vectors integrate the transgene into the genome of the target cells, which can sustain long term expression. However, it has been demonstrated that the transduction efficiency using retrovirus is relatively lower than those of other viruses. Ultrasound was recently reported to increase gene expression using plasmid DNA, with or without, a delivery vehicle. However, there are no reports, which show an ultrasound effect to retrovirus-mediated gene transfer efficiency. Retrovirus-mediated gene transfer systems were used for transfection of 293T cells, bovine aortic endothelial cells (BAECs), rat aortic smooth muscle cells (RASMCs), and rat skeletal muscle myoblasts (L6 cells) with beta-galactosidase (beta-Gal) genes. Transduction efficiency and cell viability assay were performed on 293T cells that were exposed to varying durations (5 to 30 seconds) and power levels (1.0 watts/cm(2) to 4.0 watts/cm(2)) of ultrasound after being transduced by a retrovirus. Effects of ultrasound to the retrovirus itself was evaluated by transduction efficiency of 293T cells. After exposure to varying power levels of ultrasound to a retrovirus for 5 seconds, 293T cells were transduced by a retrovirus, and transduction efficiency was evaluated. Below 1.0 watts/cm(2) and 5 seconds exposure, ultrasound showed increased transduction efficiency and no cytotoxicity to 293T cells transduced by a retrovirus. Also, ultrasound showed no toxicity to the virus itself at the same condition. Exposure of 5 seconds at the power of 1.0 watts/cm(2) of an ultrasound resulted in significant increases in retrovirus-mediated gene expression in all four cell types tested in this experiment. Transduction efficiencies by ultrasound were enhanced 6.6-fold, 4.8-fold, 2.3-fold, and 3.2-fold in 293T cells, BAECs, RASMCs, and L6 cells, respectively. Furthermore, beta-Gal activities were also increased by the retrovirus with ultrasound exposure in these cells. Adjunctive ultrasound exposure was associated with enhanced retrovirus-mediated transgene expression in vitro. Ultrasound associated local gene therapy has potential for not only plasmid-DNA-, but also retrovirus-mediated gene transfer.  相似文献   
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The essential oils extracted from the leaves and the shoots of five Abies species (Pinaceae) growing in Japan, i.e., A. firma, A. homolepis, A. veitchii, A. mariesii, and A. sachalinensis, were characterized by GC-FID and GC/MS analyses. The yields of the essential oils extracted from A. sachalinensis were the highest among them. A significant amount of α-pinene was contained in the essential oils of all the Abies species examined. In A. homolepis and A. veitchii, significant differences in the content of the essential oils were found depending on whether these were extracted from the leaves or from the shoots. Regarding the enantiomeric ratio of α-pinene, the (+)-enantiomer was predominant in the oil extracted from the leaves of A. firma, while (-)-α-pinene was present in higher amounts in the oils of A. veitchii (leaves and shoots), A. mariesii (leaves and shoots), and A. sachalinensis (shoots). The fact that there may be a quantitative and qualitative difference in the components of the essential oils extracted from the different parts of a plant was investigated by cluster analysis.  相似文献   
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