Single site laparoscopy, while in its infancy, is being explored for potential areas of application within the realm of gynecology. Gynecologic Oncology is a field with high potential benefit from the single site technique. It boasts many practical and theoretical surgical improvements, such as facilitated specimen removal, which are elaborated further in this chapter. While much more research is needed, there are exciting and uniquely useful utilities of Laparo-endoscopic Single-site Surgery (LESS) in gynecology oncology.
Rhodopsin, the mammalian dim light photoreceptor, is the canonical model for G protein-coupled receptors. Activation of rhodopsin occurs when the covalently bound inverse agonist, retinal, absorbs a photon and undergoes an 11-cis to all-trans isomerization. Two critical components of the visual cycle occur with the (1) hydrolytic release of all-trans retinaldehyde and subsequent (2) uptake of 11-cis retinaldehyde to reform the Schiff base linkage in the apoprotein opsin. Two pores on the surface of opsin are connected via the retinal channel, as discovered upon solution of the X-ray crystal structure (Park et al., Nature, 2008), and could serve as potential entryways for uptake and release. Using molecular dynamics simulations, we examined the behavior of rhodopsin in the Meta-II conformation (active) under Meta-I conditions (inactive), and discovered that the retinal binding pocket is flexible enough to allow a 180° rotation along the long axis of the retinal polyene chain. This result reconciles a discrepancy between the known polyene chain orientation from crystallographic and spectroscopic studies and opens the door for further investigation into the intermolecular interactions between the retinal ligand and the apoprotein opsin. Subsequent docking studies of both isomers of retinal into the opsin channel were then conducted to identify the mechanism for uptake and release. Our results suggest that retinal undergoes unidirectional uptake through Pore A and release through Pore B, and that aromatic sidechain interactions play a key role in stabilizing retinal within the opsin channel. These findings are significant in developing our understanding of the retinoid cycle and how ligand-receptor interactions in rhodopsin relate to G protein-coupled receptor activation.
Minimally invasive gynecologic surgery is a rapidly growing field, with new modalities and methods being explored constantly. Since the inception of laparoscopic surgery, the goal has been to minimize incision size, which has been further extrapolated to focus on less incisions with Laparoendoscopic Single-site Surgery (LESS). Single site surgery has several advantages, disadvantages, and historically relevant utility. Throughout the ensuing text, the nuances of LESS will be explored and described in detail. Our purpose in this chapter is to explore the history and utility of single site surgery. We hope to set the stage for the extensive coverage and contents of the text to elaborate on LESS and its use in modern Gynecology.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.