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Amaral MG Campos VF Seixas FK Cavalcanti PV Selau LP Deschamps JC Collares T 《Biological research》2011,44(3):229-234
Testis-mediated gene transfer (TMGT) has been used as in vivo gene transfer technology to introduce foreign DNA directly into testes, allowing mass gene transfer to offspring via mating. In this study, we used plasmid DNA (pEGFP-N1) mixed with dimethylsulfoxide (DMSO), N,N-dimethylacetamide (DMA) or liposome (Lipofectin) in an attempt to improve TMGT. Males receiving consecutive DNA complex injections were mated to normal females to obtain F0 progeny. In vivo evaluation of EGFP expression, RT-PCR and PCR were used to detect the expression and the presence of exogenous DNA in the progeny. We also evaluated possible testicular damage by histological procedures. PC R and RT-PCR analyses revealed that liposome and DMSO increased the rate of TMGT. Histological analyses demonstrated that repeated (4 times) injections of DNA complexes can affect spermatogenesis. DMSO was the most deleterious among the reagents tested. In this study, we detected the presence of transgene in the progeny, and its expression in blood cells. Consecutive injections of DNA complexes were associated with impaired spermatogenesis, suggesting requirement of optimal conditions for DNA delivery through TMGT. 相似文献
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Cerdeira LT Schneider MP Pinto AC de Almeida SS dos Santos AR Barbosa EG Ali A Aburjaile FF de Abreu VA Guimarães LC Soares Sde C Dorella FA Rocha FS Bol E Gomes de Sá PH Lopes TS Barbosa MS Carneiro AR Jucá Ramos RT Coimbra NA Lima AR Barh D Jain N Tiwari S Raja R Zambare V Ghosh P Trost E Tauch A Miyoshi A Azevedo V Silva A 《Journal of bacteriology》2011,193(24):7025-7026
In this work, we report the whole-genome sequence of Corynebacterium pseudotuberculosis bv. equi strain CIP 52.97 (Collection Institut Pasteur), isolated in 1952 from a case of ulcerative lymphangitis in a Kenyan horse, which has evidently caused significant losses to agribusiness. Therefore, obtaining this genome will allow the detection of important targets for postgenomic studies, with the aim of minimizing problems caused by this microorganism. 相似文献
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Campos VF de Leon PM Komninou ER Dellagostin OA Deschamps JC Seixas FK Collares T 《Theriogenology》2011,76(8):1552-1560
The objectives were to investigate whether: 1) nanotransfectants are more effective than other common transfection methods for SMGT; 2) NanoSMGT is able to transmit exogenous DNA molecules to bovine embryos; and 3) halloysite clay nanotubes (HCNs) can be used as a transfection reagent to improve transgene transmission. Four transfection systems were used: naked DNA (without transfectant), lipofection, nanopolymer, and halloysite clay nanotubes. Plasmid uptake by sperm and its transfer to embryos were quantified by conventional and real-time PCR, as well as EGFP expression by florescence microscopy. Furthermore, sperm motility and viability, and embryo development were investigated. Mean number of plasmids taken up was affected (P < 0.05) by transfection procedure, with the nanopolymer being the most effective transfectant (∼153 plasmids per spermatozoon). None of the treatments affected sperm motility or viability. The mean number of plasmids transmitted to four-cell stage embryos was higher (P < 0.05) in nanopolymer and HCNs than liposomes and naked DNA groups. The number of embryos carrying the transgene increased from 8–10% using naked DNA or liposomes to 40–45% using nanopolymer or HCN as transfectants (P < 0.05). There were no significant differences among transfection procedures regarding blastocyst formation rate of resulting embryos. However, no EGFP-expressing embryo was identified in any treatment. Therefore, nanotransfectants improved transgene transmission in bovine embryos without deleterious effects on embryo development. To our knowledge, this was the first time that bovine embryos carrying a transgene were produced by NanoSMGT. 相似文献
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Adriano Caliman Luciana S. Carneiro Reinaldo L. Bozelli Vinicius F. Farjalla Francisco A. Esteves 《Oikos》2011,120(11):1639-1648
Understanding the mechanisms that drive complementary interactions among species is key to the progress of the debate over the role of biodiversity in ecosystem functioning. In addition, interspecific interactions among physical ecosystem engineers have rarely been framed in the context of biodiversity experiments. Here, we provide an empirical test of how the physical niche space of species influences the effects of the biodiversity of bioturbators on cross‐habitat nutrient fluxes in benthic sediments. In the laboratory, we orthogonally manipulated the number and composition of three benthic invertebrate bioturbator species that differ in the dimensions of their bioturbating space niche; i.e. their vertical distribution in the sediment over a gradient of sediment depth and volume. The ammonium (NH4‐N) flux from the sediment to the water was positively related to bioturbator species richness only in the sediments with the deepest depth and greatest volume. The non‐additive effects of bioturbator species richness on the benthic–pelagic NH4‐N flux increased linearly with sediment depth and volume, but only in the three‐species mixtures. Furthermore, no individual species dominated the rates of H4‐N fluxes, indicating that biodiversity effects were mainly driven by complementarity. These results suggest that sediment bioturbating space mediates the magnitude of non‐additive effects among the three invertebrate species and sheds light on the importance of physical niche space in modulating the positive effects of biodiversity on ecosystem functioning. 相似文献
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Loschi RH Monteiro JV Rocha GH Mayrink VD 《Biometrical journal. Biometrische Zeitschrift》2007,49(6):824-839
In this paper we analyze the fraction of non-disjunction in Meiosis I assuming reference (non-informative) priors. We consider Jeffreys's approach to built a non-informative prior (Jeffreys's prior) for the fraction of non-disjunction in Meiosis I. We prove that Jeffreys's prior is a proper distribution. We perform Monte Carlo studies in order to compare Bayes estimates obtained assuming Jeffreys's and uniform priors. We consider full Bayesian significance test (FBST) and Bayes factor (BF) for testing precise hypothesis on the fraction of non-disjunction in Meiosis I. The ultimate goal of this paper is to compare these two test procedures through simulation studies using both prior specifications. An application to Down Syndrome data is also presented. 相似文献
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Taxonomic status and phylogenetic relationships of Marmosa agilis peruana Tate, 1931 (Didelphimorphia: Didelphidae), with comments on the morphological variation of Gracilinanus from central–western Brazil 下载免费PDF全文
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Andressa C. Lannes Bruno Leal Juliana S. Novais Viviane Lione Georgia C. T. S. Monteiro André L. Lourenço Plínio C. Sathler Alessandro K. Jordão Carlos R. Rodrigues Lúcio M. Cabral Anna Claudia Cunha Vinicius Campos Vítor F. Ferreira Maria Cecília B. V. de Souza Dilvani O. Santos Helena C. Castro 《Current microbiology》2014,69(3):357-364
Bacterial multiresistance is a health problem worldwide that demands new antimicrobials for treating bacterial-related infections. In this study, we evaluated the antimicrobial activity and the theoretical toxicology profile of N-substituted-phenylamino-5-methyl-1H-1,2,3-triazole-4-carbohydrazide derivatives against gram-positive and gram-negative bacteria clinical strains. On that purpose we determined the minimum inhibitory (MIC) and bactericidal (MBC) concentrations, the in vitro cytotoxicity, and in silico risk profiles, also comparing with antimicrobial agents of clinical use. Among the 16 derivatives analyzed, four nitrofurans (N–H–FUR–NO2, N–Br–FUR–NO2, N–F–FUR–NO2, N–Cl–FUR–NO2) showed promising MIC and MBC values (MIC = MBC = 1–16 μg/mL). The experimental data revealed the potential of these derivatives, which were comparable to the current antimicrobials with similar bactericidal and bacteriostatic profiles. Therefore, these molecules may be feasible options to be explored for treating infections caused by multiresistant strains. Our in vitro and in silico toxicity reinforced these results as these derivatives presented low cytotoxicity against human macrophages and low theoretical risk profile for irritant and reproductive effects compared to the current antimicrobials (e.g., vancomycin and ciprofloxacin). The molecular modeling analysis also revealed positive values for their theoretical druglikeness and drugscore. The presence of a 5-nitro-2-furfur-2-yl group seems to be essential for the antimicrobial activity, which pointed these acylhydrazone derivatives as promising for designing more potent and safer compounds. 相似文献
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