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101.
Cazzato A Capobianco ML Zambianchi M Favaretto L Bettini C Barbarella G 《Bioconjugate chemistry》2007,18(2):318-322
Oligomers of thiophene are widely studied compounds for their electronic and optoelectronic properties. Despite their strong fluorescence, their use as markers for biomolecules, especially for oligonucleotides (ONs), is still largely unexplored. Here, we describe the synthesis of a series of ON molecular beacons employing different oligothiophenes as fluorescent probes and discuss their fluorescence emissions in comparative experiments with and without dabcyl as a quencher, in their hairpin and linear conformations, and as duplexes after hybridization with a complementary target. 相似文献
102.
Rakosy-Tican E Aurori CM Dijkstra C Thieme R Aurori A Davey MR 《Plant cell reports》2007,26(5):661-671
Potato is one of the main targets for genetic improvement by gene transfer. The aim of the present study was to establish
a robust protocol for the genetic transformation of three dihaploid and four economically important cultivars of potato using
Agrobacterium tumefaciens carrying the in vivo screenable reporter gene for green fluorescent protein (gfp) and the marker gene for neomycin phosphotransferase (nptII). Stem and leaf explants were used for transformation by Agrobacterium tumefaciens strain LBA4404 carrying the binary vector pHB2892. Kanamycin selection, visual screening of GFP by epifluorescent microscopy,
PCR amplification of nptII and gfp genes, as well as RT-PCR and Southern blotting of gfp and Northern blotting of nptII, were used for transgenic plant selection, identification and analysis. Genetic transformation was optimized for the best
performing genotypes with a mean number of shoots expressing gfp per explant of 13 and 2 (dihaploid line 178/10 and cv. ‘Baltica’, respectively). The nptII marker and gfp reporter genes permitted selection and excellent visual screening of transgenic tissues and plants. They also revealed the
effects of antibiotic selection on organogenesis and transformation frequency, and the identification of escapes and chimeras
in all potato genotypes. Silencing of the gfp transgene that may represent site-specific inactivation during cell differentiation, occurred in some transgenic shoots of
tetraploid cultivars and in specific chimeric clones of the dihaploid line 178/10. The regeneration of escapes could be attributed
to either the protection of non-transformed cells by neighbouring transgenic cells, or the persistence of Agrobacterium cells in plant tissues after co-cultivation. 相似文献
103.
Giulio Cerullo Cristian Manzoni Larry Lüer Dario Polli 《Photochemical & photobiological sciences》2007,6(2):135-144
In this paper we discuss how to push the temporal resolution limits of transient absorption spectroscopy in order to detect very fast processes (energy relaxation, energy or charge transfer, vibrational coherence) taking place in molecules of biological relevance. After reviewing the main principles of femtosecond pump-probe spectroscopy, we describe an experimental setup based on two synchronized non-collinear optical parametric amplifiers (NOPAs). Each NOPA can be independently configured to generate ultra-broadband sub-10 fs visible pulses, tunable 10-15 fs visible pulses, tunable 15-40 fs near-infrared pulses (900-1500 nm). This system enables to perform pump-probe experiments over nearly two octaves of spectrum with sub-20 fs temporal resolution. We then present an application example highlighting the capability of this instrument to track excited state dynamics in biomolecules on the sub-100 fs timescale: the study of carotenoid-bacteriochlorophyll energy transfer processes in peripheral light-harvesting complexes (LH2) from purple bacteria. We show that, by comparing excited-state dynamics of the carotenoids in organic solvents and inside the LH2 complexes, it is possible to visualize in the time domain the primary events in photosynthesis. 相似文献
104.
Vallejos-Almirall Alejandro Riquelme Margarita Uribe Elena Agurto-Muñoz Cristian Rosas Anali Vergara Carola 《Journal of applied phycology》2022,34(5):2371-2382
Journal of Applied Phycology - Ultraviolet (UV) radiation generates cyclobutane pyrimidine dimer (CPD) photoproducts in the DNA of skin cells, causing photoaging and non-melanoma skin cancer.... 相似文献
105.
Marie-Anne Tartanson Laurence Soussan Matthieu Rivallin Sophie Pecastaings Cristian V. Chis Diego Penaranda Christine Roques Catherine Faur 《Applied and environmental microbiology》2015,81(20):7135-7142
The bactericidal activity of an Al2O3-TiO2-Ag granular material against an Escherichia coli strain was confirmed by a culture-based method. In particular, 100% of microorganisms were permanently inactivated in 30 to 45 min. The present work aimed to investigate the mechanisms of the bactericidal action of this material and their dynamics on Escherichia coli using different techniques. Observations by transmission electron microscopy (TEM) at different times of disinfection revealed morphological changes in the bacteria as soon as they were put in contact with the material. Notably highlighted were cell membrane damage; cytoplasm detachment; formation of vacuoles, possibly due to DNA condensation, in association with regions exhibiting different levels of electron density; and membrane lysis. PCR and flow cytometry analyses were used to confirm and quantify the observations of cell integrity. The direct exposure of cells to silver, combined with the oxidative stress induced by the reactive oxygen species (ROS) generated, was identified to be responsible for these morphological alterations. From the first 5 min of treatment with the Al2O3-TiO2-Ag material, 98% of E. coli isolates were lysed. From 30 min, cell viability decreased to reach total inactivation, although approximately 1% of permeable E. coli cells and 1% of intact cells (105 genomic units · ml−1) were evidenced. This study demonstrates that the bactericidal effect of the material results from a synergic action of desorbed and supported silver. Supported silver was shown to generate the ROS evidenced. 相似文献
106.
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108.
Gene Expression Changes in Progression of Cervical Neoplasia Revealed by Microarray Analysis of Cervical Neoplastic Keratinocytes
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110.
Stasi LP Bhimani K Borriello M Canciani L Caselli G Colace F Ferioli C Kaswala M Mennuni L Piepoli T Pucci S Salvi M Shirsath V Zanelli T Zerbi S 《Bioorganic & medicinal chemistry letters》2011,21(21):6336-6340
The construction of a EP(4) antagonists pharmacophore model and the discovery of a highly potent oxepinic series of EP(4) antagonists is discussed. Compound 1a exhibits an excellent selectivity profile toward EP(2) receptor subtype and low cytochrome P450 inhibition potential. 相似文献