Topography, Molecular

For cyclohexane derivatives, convulsive activity is associated, apparently specifically, with a particular molecular topography that is only achieved with the aaaeee arrangement of substituents However, the norbornene and camphene carbon skeletons apparently permit the attainment of a similar topography... 

Figure 5. Molecular topographies of phenol, water, and phenol-water clusters as obtained from theoretical electron density. (Reproduced with permission from Ref. 245 American Chemical Society, 2005.)...

Figure 7. Molecular topographies of protonated water clusters. (Results from Ref. 297.)...

Bader et al. first clarified the molecular topography of density distributions. For example, they defined the width and length of a molecule in terms of the density contours of 0.002 a.u. The density difference maps... 

Eisenman EM, Hawkes R (1993) Antigenic compartmentation in the mouse cerebellar cortex Zebrin and HNK-1 reveal a complex, overlapping molecular topography. J. Comp. Neurol, 335, 586-605. 

Compared to 66.5% of gene therapy clinical trials aiming at the treatment of cancer, only 2 of the 12 siRNA clinical trials are designed for cancer therapy, indicating the siRNA cancer therapy is still in its infancy. Same as the therapeutic application of pDNA, the major bottleneck for a successful siRNA therapy is the efficient delivery. Scientists have gained extensive experiences in the delivery of pDNA and these experiences can be utilized for the delivery of plasmid-based shRNA. However, the same experience cannot be transferred to siRNA directly since siRNA is very different from pDNA in terms of the molecular weight, molecular topography, and in vivo stability. In addition, compared to pDNA, siRNA is more difficult to be condensed into nanosized complex. Nevertheless, many nonviral vectors have been developed for siRNA delivery and one of them was recently approved for phase I clinical trial. 

For a working definition of molecular structure, we have adopted the one given by Eliel The structure of a molecule is completely defined by the number and kind of atoms and the linkages between them . We have applied the term molecular topography to the three-dimensional arrangement of the atoms in a particular conformation the term configuration is also used. The term molecular topology refers to the set of atoms and connections within the molecular skeleton, that is, the molecular structure as defined by Eliel. 

K. M. Wiencek and M. Fletcher, Effects of substratum wettability and molecular topography on the initial adhesion of bacteria to chemically defined substrata... 

Cunningham, B. A., Hoffman, S., Rutishauser, U., Hemperly, J. J., and Edelman, G. M., 1983, Molecular topography of the neural cell adhesion molecule N-CAM Surface orientation and location of sialic acid-rich and binding regions, Proc. Natl. Acad. Sci. USA 80 3116-3120. 

Song, P.-S., The molecular topography of phytochrome chromophore and apoprotein, J. Photochem. Photobiol, 2, 43, 1989. 

Singh, B. R. and DasGupta, B. R., 1989b, Molecular topography and secondary structure comparisons of botulinum toxin types A, B and E. Mol. Cell. Biochem. 86 87-95. 

Singh, B.R., Kokan-Moore, N.P. and Bergdoll, M.S. 1988b. Molecular topography of toxic shock syndrome toxin as revealed by spectroscopic studies. Biochemistry 27 8730-8735. 

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