---

a catastrophe happened years ago in the palace of rich and famous family of Cenci in Rome that ignited the creation of a play named The Cenci by two significant playwrights with different approaches and writing ideas. This study is a comparative analysis of different approaches of these two writers: Percy Bysshe Shelley’s theory, regarding the popular romanticism movement in the 19th century England and Antonin Artaud’s theory, considering his beliefs on the theater of cruelty. The purpose of this paper is to find the intellectual similarities and differences between these two writers in their approach toward the same historical event and their standpoint on its link to the theater and the text. Poetic verbal descriptions are significant in Shelley’s work; while Artaud, with his opposition to the literature of theater, tries to emphasize on directing and performance and writing the play with his favorite functions and performing methods. The comparative analysis of these two plays will describe their thematic differences. The results of this study suggest that in order to subtract the violence of Cenci’s event, Percy Bysshe Shelley has limited himself to the events that only take place in dialogues and those which show the actions of characters in different acts just in speech; however, Antonin Artaud presents the violent actions in the present time and with a redoubled rage by using mute characters and omitting subsidiary scenes.

---

Objective: CREB1 is an important downstream protein for many signaling pathways. By designing efficient siRNAs against CREB1, it may be possible to assess the role of molecules involved in signaling pathways in different cell types. In this research the efficiency of CREB1 knockdown by two different siRNAs in K562 cells has been studied. Materials and Methods: siRNAs have been designed according to the criteria suggested by Reynolds et al. K562 cells were transfected by siRNA using Lipofectamine 2000. The efficiency of CREB knockdown has been assessed by quantitative relative Real-time PCR. Results: Our results have shown that only one of the siRNAs has a high level of inhibitory effect on CREB1 gene expression. The expression of CREB1 by this siRNA was knocked-down by 87% in K562 cells. Conclusion: In this research, although two siRNAs were designed according to the Reynolds et al. criteria, only one showed an inhibitory effect. Reasons other than the aforementioned criteria may be involved in effectiveness of siRNAs.