It is well established that many metal ions accelerate the spontaneous degradation of RNA. This property has been exploited in several ways to garner information about RNA structure, especially in regards to the location of site-specifically bound metal ions, the presence of defined structural motifs, and the occurrence of conformational changes in structured RNAs. In this chapter, we review th...

introduction: the value of embryonic stem-like cells in cloning is obvious. production of cloned animals can be achieved by introduction of these cells into a tetraploid embryo. tetraploid embryo is used as a feeder for development of embryonic stem-like cells and can be produced in vitro by electro-fusion of 2-cell embryos. the aim of this study was to ass,essthe effect of voltage alteration a...

the aim of this study was to examine the possible morphological and morphometric changes resulting from vitrification of embryos at the cleavage stage. in this study, 30 mice early-cleavage embryos at different stages of cleavage, resulting from in vitro fertilization (ivf) techniques, were examined before and after vitrification. digital images were taken from embryos before and after vitrific...

Most of the small ribozymes, including those that have been investigated as potential therapeutic agents, appear to be rather poor catalysts. These RNAs use an internal phosphoester transfer mechanism to catalyze site-specific RNA cleavage with apparent cleavage rate constants typically <2 min(-1). We have identified variants of one of these, the Neurospora Varkud satellite ribozyme, that self-...

background and aims: the caspases are unique proteases that mediate the host cell apoptosis during viral infection. in this study, we identified the caspase cleavage motifs of h5n1 and h9n2 influenza viruses isolated during 1998-2012. materials and methods: amino acid sequences of the eleven proteins encoded by the viruses as the caspase substrates downloaded from ncbi. the caspase cleavage mot...

Background: The aim of our study was to compare the resulting from transfer of embryos that cryopereserved in cleavage stage after thawing and transfer of embryos after thawing and culture in sequentional media until blastocyst formation. Materials and Methods: In this prospective clinical study, we have evaluated 128 cycles in women undergone in vitro fertilization (IVF) or intracytoplasmic sp...

the aim of this study was to compare the effect of time of parthenogenetic activation (22 hr versus 27 hr after in vitro maturation-ivm) on in vitro development of ovine oocytes using either single (ionomycin 5 ?m for 5 min or ethanol 7% for 7 min) or combined (ionomycin and ethanol with 6-dmap 2 mm for 3 hr) activation treatments. the abattoir-derived in vitro matured activated oocytes were cu...