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Molecular Biology Reports - Parkinson’s disease (PD) is a chronic neurodegenerative disease. Unfortunately, the effectiveness of anti-Parkinson treatments gradually diminishes owing to the...  相似文献   
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Most of the commercialized Bt crops express cry genes under 35S promoter that induces strong gene expression in all plant parts. However, targeted foreign gene expression in plants is esteemed more important as public may be likely to accept ‘less intrusive’ expression of transgene. We developed plant expression constructs harboring cry1Ac gene under control of wound-inducible promoter (AoPR1) to confine Bt gene expression in insect wounding parts of the plants in comparison with cry1Ac gene under the control of 35S promoter. The constructs were used to transform four Turkish cotton cultivars (GSN-12, STN-468, Ozbek-100 and Ayhan-107) through Agrobacterium tumefaciens strains GV2260 containing binary vectors p35SAcBAR.101 and AoPR1AcBAR.101 harboring cry1Ac gene under control of 35S and AoPR1, respectively. Phosphinothricin (PPT) was used at concentration of 5 mg L?1 for selection of primary transformants. The primary transformants were analyzed for transgene presence and expression standard molecular techniques. The transformants exhibited appreciable mortality rates against larvae of Spodoptera exigua and S. littoralis. It was found that mechanical wounding of T 1 transgenic plants was effective in inducing expression of cry1Ac protein as accumulated levels of cry1Ac protein increased during post-wounding period. We conclude that use of wound-inducible promoter to drive insecticidal gene(s) can be regarded as a valuable insect-resistant management strategy since the promoter activity is limited to insect biting sites of plant. There is no Bt toxin accumulation in unwounded plant organs, seed and crop residues, cotton products and by-products, thus minimizing food and environmental concerns.  相似文献   
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Heat‐shock proteins (HSP) are molecular chaperones for protein molecules. These proteins play an important role in protein–protein interactions such as, folding and assisting in the establishment of proper protein conformation and prevention of unwanted protein aggregation. A small HSP gene GHSP26 present in Gossypium arboreum responds to dehydration. In the present study, an attempt was made to overcome the problem of drought stress in cotton. A cDNA of GHSP26 was isolated from G. arboreum, cloned in plant expression vector, pCAMBIA‐1301 driven by the cauliflower mosaic virus 35S promoter and introduced into Gossypium hirsutum. The integration and expression studies of putative transgenic plants were performed through GUS assay; PCR from genomic DNA, and quantitative real‐time PCR analysis. Transgenic cotton plants showed an enhanced drought tolerance, suggesting that GHSP26 may play a role in plant responsiveness to drought. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010  相似文献   
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The ability of the flavonoid lentinan (LAN) to enhance the repair of paclitaxel (PAC)‐induced DNA damage and apoptosis in mouse bone marrow cells was investigated. Moreover, the possible mechanism underlying this modulation was determined. LAN was neither genotoxic nor apoptogenic at doses equivalent to 1 or 2 mg/kg/day. Pretreatment of mice with LAN significantly enhances the repair of PAC‐induced DNA damage and bone marrow suppression in a dose dependent manner. Moreover, LAN affords significant protection against PAC‐induced apoptosis. A significant increase of reactive oxygen species and a decrease in reduced glutathione levels were observed after PAC treatment and prior administration of LAN before PAC challenge ameliorated these oxidative stress markers. Conclusively, our study provides, for the first time, that LAN enhances the repair of PAC‐induced DNA damage and apoptosis that resides, at least in part, on its ability to modulate the cellular antioxidant levels and consequently protect bone marrow cells from PAC genotoxicity. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:370‐377, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21499  相似文献   
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This experiment was performed to evaluate the possible embryotoxic and teratogenic effects of doxycycline during rat development. Twenty‐one female rats were used and distributed into three groups equally (seven animals/group). The low dose group received doxycycline at a dose of 5 mg/kg bw/day orally from the 6th to 14th day of gestation. The high dose group received 10 mg/kg bw/day orally for the same period, the Control group received 1 mL distilled water orally for the same period. The dams were dissected on the 20th day of gestation and their fetuses were subjected to morphological, skeletal, and histological examination. Moreover, DNA damage analysis of liver cells of pregnant rats and their fetuses or fetal skull was assessed by Comet assay. The obtained results showed a significant decrease in fetal body weight, several morphological anomalies, and severe lack of ossification on the skull bones, phalanges, and sternum bone as well as shortness in the ulna and radius bones. Histological studies of pregnant rats revealed congestion and dilatation of the central vein of the liver lobules and fatty degeneration of the hepatocytes. In addition, 20 day‐fetuses showed a marked increase of necrotic hepatocytes associated with an increased average of megakaryocytes and periportal leukocytic infiltration. Moreover, doxycycline induced a significant increase in the percentage of DNA damage and tail length of examined samples. Conclusively, doxycycline caused certain fetal abnormalities, so it is advisable to avoid using this drug during pregnancy.  相似文献   
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In Vitro Cellular & Developmental Biology - Plant - A simple and improved Agrobacterium-mediated transformation protocol of tomato (Solanum lycopersicum) cultivar Rio Grande was developed to...  相似文献   
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In this study, micromorphological features of the leaf epidermal cells of 17 species of Iranian Cotoneaster were determined. The studied species were compared with each other and with phylogenetic relationships established by previous studies. Three populations of C. integerrimus and C. multiflorus were studied as representatives of C. subgen. Cotoneaster and Chaenopetalum, respectively. To evaluate quantitative and qualitative characters, multiple correspondence analysis (MCA) and factor analysis of mixed data (FAMD) were performed. Finally, relationships among the taxa were illustrated by hierarchical clustering analysis. Three stomatal types were identified, i.e. anomocytic, stephanocytic and actino‐stephanocytic. The wax and cuticle density was higher in species from semi‐moist habitats than in those from dry and semi‐dry habitats. The patterns formed by the anticlinal walls of the epidermal cells were sinuous, repand and straight‐curved. Interestingly, there was a significant relationship between the length of leaves, the density of the indumentum and the pattern formed by the anticlinal cell walls. The leaves of species with large leaves also have lower hair density and more curved anticlinal cell walls. It appears probable that climatic conditions affected the evolution of leaf micro‐morphological characters during the early diversification of the genus, but that these characters have subsequently been permanently fixed by phylogenetic constraints and thus appear diagnostic for extant species.  相似文献   
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