Differences in the Difficulty of Accessing Various 3-Dimensional Locations Under Mirror-Image Conditions During Laparoscopic Surgery.

BACKGROUND: Laparoscopic colon surgery frequently requires performing maneuvers under mirror-images conditions; the complexity differs depending on the surgical site location in the abdominal cavity. However, no previous reports have examined this. METHODS: Eleven surgeons participated in this study. Operations were performed on 25 points placed at the bottom and sides of a laparoscopic training box under mirror-image conditions. The mean time-point required to operate at each point and variation between surgeons were evaluated. RESULTS: When the right hand was used, time-points to touch the right side-superficial ends were 0.50 to 0.58 and 0.27 to 0.45 for the other sites. With the left hand, time-points to touch the left side-superficial ends were 0.58 to 0.63 and 0.28 to 0.51 for the other sites, indicating that the most difficult manipulation was at the proximal site of the surgical port. The variation in the difficulty according to the spots increased with a decrease in the surgeon's experience (right hand, r =-0.248; left hand, r =-0.491). CONCLUSIONS: In performing laparoscopic surgery under mirror-image conditions, the technical difficulty varies by location, and operating in locations close to the forceps port is the most difficult.

Analysis of the Positional Relationship Among the Operator, Camera, and Monitor: Overcoming the Difficulties of Mirror-image Conditions During Laparoscopic Surgery.

BACKGROUND: Although methods to overcome difficulties associated with mirror-image conditions have been investigated, the ideal spatial relationship among the operator line of sight, monitor location, and camera location remains unclear. Moreover, the best training method for improving laparoscopic surgical skills under varying operator line of sight, camera, and monitor positions is unknown. We aimed to investigate the role of laparoscopic training under mirror-image conditions in improving surgical efficiency and whether prior surgical experience affects such training. METHODS: This prospective study was conducted at the Department of Surgical Oncology, Tokyo University, Japan. Twenty-five surgeons participated. Novice (n=14), trained (n=7), and expert (n=4) participants performed the simulated task in a box trainer while varying the positional relationships among the surgeons, camera, and monitor. Five patterns were repeatedly performed 5 times per day for 4 days over 2 weeks. RESULTS: The most significant differences in terms of the time required to complete the task under mirror-image conditions among the 3 groups were on day 1 (novices: 185.8 s, trained: 79.7 s, and experts: 46.5 s, P=0.009). However, after 4 days of training, the corresponding times did not differ among the 3 groups (26.0, 30.7, and 23.1 s, respectively; P=0.415). Laparoscopic training was sufficiently effective under mirror-image conditions. CONCLUSIONS: Mirror-image surgical conditions provided the most difficult setting, because surgeons and assistants often became disoriented, and task performance was most degraded. However, just 4 days of training was found to be sufficient to overcome the difficulties encountered while performing laparoscopic procedures under mirror-image conditions.

Halogenated polycyclic aromatic hydrocarbons in edible aquatic species of two Asian countries: Congener profiles, biomagnification, and human risk assessment.

Seventy-five contaminants including chlorinated/brominated/parent polycyclic aromatic hydrocarbons (Cl/Br/PAHs) were investigated in 29 edible aquatic species from the Indian Ocean near Sri Lanka and 10 species from the Pacific Ocean near Japan. Concentrations of total ClPAHs and BrPAHs in the samples were 2.6-57 and 0.30-9.5 ng/g-dry weight from the Indian Ocean, and 0.35-18 and 0.03-3.3 ng/g-dry weight from the Pacific Ocean, respectively. Comparing the profiles of Cl/BrPAHs among the samples, congeners of chlorinated and brominated pyrene were predominant components and enhanced the potential for biomagnification in the sample from the off-shore pelagic environment in the Indian Ocean. The incremental lifetime cancer risks estimated by intake of the targets in consuming aquatic organisms showed that approximately one-third of studied organisms exceeded the acceptable risk level for Sri Lankans.

Production of protective antibodies against Porphyromonas gingivalis strains by immunization with recombinant gingipain domains.

We studied the effect of antibodies against Porphyromonas gingivalis gingipain domains, preparing them against three recombinant fragments of RgpA (catalytic domain, r-Rgp CAT; hemagglutinin domains, r-Rgp 44 and r-Rgps 15-27) and one fragment of Kgp (catalytic domain, r-Kgp CAT). Enhancement of opsonization and killing by human polymorphonuclear leukocytes were measured in the noninvasive FDC 381 and invasive W50 strains of P. gingivalis. Anti-r-Rgp 44 was the most effective in both strains of P. gingivalis. The present findings lead us to recommend RgpA 44 as a candidate immunogen for vaccines against P. gingivalis.