Ergonomic port placement in laparoscopic colorectal surgery.

AIM: Port placement in laparoscopic surgery has important ergonomic implications. A manipulation angle (MA) of 60° has been shown to maximize task efficiency. We calculated the MA used during various stages of both right hemicolectomy (RH) and high anterior resection (AR). METHOD: We compared two methods of port placement for each operation. RH-PP1 included ports in the left iliac fossa and left upper quadrant. RH-PP2 included ports suprapubically and in the left iliac fossa. We calculated the MA of each of these methods in mobilizing both the caecum and hepatic flexure. AR-PP1 included ports in the right iliac fossa and right upper quadrant. AR-PP2 included ports suprapubically and in the right iliac fossa. We calculated the MA of each of these methods in mobilizing the splenic flexure, descending-sigmoid junction and the recto-sigmoid junction. RESULTS: For RH-PP1, the mean MA for mobilizing the caecum and hepatic flexure was 38° and 52°, respectively. For RH-PP2, the mean MA for mobilising the caecum and hepatic flexure was 58° and 44°, respectively. For AR-PP1, the mean MA for mobilizing the splenic flexure, the descending-sigmoid junction and the recto-sigmoid junction was 77°, 41° and 18°, respectively. For AR-PP2, the mean MA for mobilizing the splenic flexure, the descending-sigmoid junction and the recto-sigmoid junction was 40°, 56° and 34°, respectively. CONCLUSION: There are no two port placements that will allow for an ideal MA at every stage of mobilization for either right- or left-sided resection.

An optimized fluorescence in situ hybridization procedure for detecting rye chromosomes in wheat.

In situ hybridization with an interspersed repeat clone from rye, pSc119, was shown to be useful for detecting rye chromosomes introduced into wheat. However, since pSc119 also shows strong hybridization to a few sites in certain wheat chromosomes, small rye chromosome segments added to wheat may be difficult to detect. In this study, detection of rye chromosomes present in triticale and triticale X wheat hybrids was accomplished with the use of a subfragment from pSc119 (pSc119.1) whose sequence is dispersed throughout the rye chromosomes and only weakly cross-hybridizes to a few telomeric and centromeric regions of wheat. The in situ hybridization conditions were optimized to readily distinguish rye chromosomes from wheat chromosomes without the need for intensive analysis of hybridization patterns. Rye chromosomes were readily detected using fluorescence in situ hybridization. Fluorescence detection provided increased sensitivity over enzymatic detection and allowed signals to be amplified with repeated use of biotinylated anti-avidin antibody and avidin-FITC. Detection of rye chromatin was further optimized by doubling the probe concentration. Finally, double exposure photography of the same cell with two different filters provided another means to further increase the contrast between rye and wheat chromosomes.