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131.
A system for population control of insects is proposed. It is based on transgenic insects expressing an enzyme which converts an inactive pro-drug into an active, toxic form. A model system is presented which relies on transposon-mediated integration of a bacterial cytosine deaminase (CD) gene into the genome of Drosophila melanogaster. We demonstrate female-specific sterility and transgene-dependent lethality when flies carrying the CD gene under a Drosophila female-specific promoter/enhancer are treated with 5-Fluorocytosine, a low-toxicity nucleoside analogue which is converted to toxic 5-Fluorouracil by the enzyme. The approach can be used with existing pro-insecticides and appropriate converting enzymes in combination with established mass rearing technology, for targeted, environmentally acceptable control of insects of economic and public health importance. 相似文献
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Papaziogas B Koutelidakis IM Giamarellos-Bourboulis EJ Lazaridis C Koussoulas V Galanis I Giamarellou H Atmatzidis K 《Prostaglandins, leukotrienes, and essential fatty acids》2004,71(4):221-225
AIM OF THE STUDY: To evaluate the early effect of inguinal hernia repair by the tension-free method compared to the conventional Andrew's technique on lipid peroxidation. PATIENTS-METHODS: Thirty-four patients subjected to elective hernia repair were enrolled in the study divided in two groups. Group A (n=18) underwent hernia repair by the tension-free method using a polypropylene mesh. Group B (n=16) underwent hernia repair by the Andrew's technique (i.e. a modification of the Bassini's technique). Venous blood samples were drawn preoperatively and at 12, 24 and 48 h postoperatively. Malondialdehyde (MDA) was estimated by the thiobarbiturate assay. RESULTS: Neutrophil counts were significantly higher in patients of group B compared to group A at 12 and 48 h postoperatively. Concentrations of fibrinogen were similar between the two groups. MDA was significantly higher in patients of group B hours compared to group A at 12, 24 and 48 h postoperatively. Positive correlation was found between neutrophil counts and MDA at 12 h (r: +0.43, P: 0.015) and 48 h (r: +0.496, P: 0.005) but not at 24 h. No correlation was found between serum fibrinogen and MDA. CONCLUSION: Hernia repair by the Andrews's technique elicits a sustained triggering of lipid peroxidation, compared to the tension-free method. 相似文献
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Charalambos Magoulas Ada Loverre-Chyurlia Sumaia Abukashawa Laure Bally-Cuff Donal A. Hickey 《Journal of molecular evolution》1993,36(3):234-242
Summary Previous studies have demonstrated that the expression of the -amylase gene is repressed by dietary glucose in Drosophila melanogaster. Here, we show that the -amylase gene of a distantly related species, D. virilis, is also subject to glucose repression. Moreover, the cloned amylase gene of D. virilis is shown to be glucose repressible when it is transiently expressed in D. melanogaster larvae. This cross-species, functional conservation is mediated by a 330-bp promoter region of the D. virilis amylase gene. These results indicate that the promoter elements required for glucose repression are conserved between distantly related Drosophila species. A sequence comparison between the amylase genes of D. virilis and D. melanogaster shows that the promoter sequences diverge to a much greater degree than the coding sequences. The amylase promoters of the two species do, however, share small clusters of sequence similarity, suggesting that these conserved cis-acting elements are sufficient to control the glucose-regulated expression of the amylase gene in the genus Drosophila.Offprint requests to: D.A. Hickey 相似文献
135.
Length polymorphism in the threonine-glycine-encoding repeat region of theperiod gene inDrosophila 总被引:4,自引:0,他引:4
Rodolfo Costa Alexandre A. Peixoto Justin R. Thackeray Raymond Dalgleish Charalambos P. Kyriacou 《Journal of molecular evolution》1991,32(3):238-246
Summary Single-fly polymerase chain reaction amplification and direct DNA sequencing revealed high levels of length polymorphism in
the threonine-glycine encoding repeat region of theperiod (per) gene in natural populations ofDrosophila melanogaster. DNA comparison of two alleles of identical lengths gave a high number of synonymous substitutions suggesting an ancient
time of separation. However detailed examination of the sequences of different Thr-Gly length variants indicated that this
divergence could be understood in terms of four deletion/insertion events. InDrosophila pseudoobscura a length polymorphism is observed in a five-amino acid degenerate repeat, which corresponds tomelanogaster's Thr-Gly domain. In spite of the differences betweenD. melanogaster andD. pseudoobscura in the amino acid sequence of the repeats, the predicted secondary structures suggest evolutionary and mechanistic constraints
on theper protein of these two species. 相似文献
136.
Nancy Wedel Paul Toselli Charalambos Pothoulakis Barbara Faris Pamela Oliver Carl Franzblau Thomas Lamont 《Experimental cell research》1983,148(2):413-422
The mechanism by which Clostridium difficile toxin B causes cells in culture to round was investigated. Cultured human lung fibroblasts and rabbit aortic smooth muscle cells were treated with partially purified or purified toxin B and monitored by light and transmission electron microscopy (TEM). Both preparations caused progressive cell rounding which correlated with disorganization of actin-containing myofilament bundles. Thin myofilaments became fragmented and finally disappeared (after 24 h) and dense bodies became more prominent, while all other organelles appeared unaffected. 相似文献
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Charalambos Neophytou Elnura Torutaeva Silvia Winter Harald Meimberg Hubert Hasenauer Manuel Curto 《Tree Genetics & Genomes》2018,14(6):82
Microsatellite markers are still the marker of choice for many research questions in the field of forest genetics. However, the number of available markers is often low for species that have not been studied intensively like the tree of heaven (Ailanthus altissima). During the last decade, next-generation sequencing (NGS) has offered advanced techniques for efficiently identifying microsatellite markers and accurately genotyping samples. Here, we identify new microsatellite markers for the tree of heaven by applying an NGS-based method using the Illumina MiSeq platform. NGS technology was proved to be an effective method for fast and cost-efficient identification of microsatellite markers by implementing a genotyping-by-sequencing approach based on Illumina amplicon sequencing (SSR-GBS). We screened three populations from Eastern Austria for genetic variation at 19 newly identified microsatellite loci. We tested two different genotyping approaches: (1) considering only allele lengths (forming a so-called “allele length dataset”), (2) taking also single nucleotide polymorphisms (SNPs) within the amplified fragments into account (forming a so-called “SNP dataset”). The results revealed higher values for all genetic diversity parameters, as well as a better resolution of genetic assignment, when the latter approach was followed. Thus, by taking advantage of sequence information which is provided by SSR-GBS, one may achieve considerable gains in performance using the same marker set. The developed markers provide a cost-efficient tool for genotyping populations of tree of heaven and the approach presented here promises to be of high value for medium throughput genotyping applications in non-model forest tree species. We will use this method to widen the perspectives for further population genetic investigations of the tree of heaven. 相似文献
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We analyzed 28 species of the genus Drosophilafor the presence of the Tc1-like transposable element Minosusing Southern blot hybridization under high stringency conditions. The Minostransposon was found in members of both the Drosophilaand the Sophophorasubgenus showing a distribution that is wider if compared to other well-studied Drosophilatransposons such as the Pelement, hoboand mariner. The presence of Minos-hybridizing sequences was discontinuous in the Sophophorasubgenus, especially in the melanogasterspecies group. Using the Polymerase Chain Reaction we amplified a portion corresponding to the putative Minostransposase from different Drosophilaspecies. Cloning and sequence analysis of randomly selected Minoscopies from D. mojavensisis, D. saltansand D. willistonisupports the idea that event(s) of horizontal transfer may have contributed to the spreading of this transposon in the Drosophilagenus.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Regent Lee Roman Fischer Philip D. Charles David Adlam Alessandro Valli Katalin Di Gleria Rajesh K. Kharbanda Robin P. Choudhury Charalambos Antoniades Benedikt M. Kessler Keith M. Channon 《Clinical proteomics》2017,14(1):22