Makoto Kosuge

A comprehensive gene expression analysis of human hepatocellular carcinoma cell lines as components of a bioartificial liver using a radial flow bioreactor

Background/Aims: The cells constituting a bioartificial liver are crucial for an effective liver support system. We compared global gene expression profiles in a radial flow bioreactor or a monolayer culture of three functional liver cell lines previously established from human hepatocellular carcinoma.

A comparison of laparoscopic energy devices on charges in thermal power after application to porcine mesentery.

Introduction: Advances in energy devices have played a major role in the rapid expansion of laparoscopic surgery. However, complications due to these energy devices are occasionally reported, and if the characteristics of these devices are not well understood, serious complications may occur. This study evaluated various typical energy devices and measured temperature rises in the adjacent tissue and in the devices themselves. Equipment and Methods: We used the following 7 types of energy devices: AutoSonix (AU), SonoSurg (SS), Harmonic Scalpel (HS), LigaSure Atlas (LA), LigaSure Dolphin Tip (LD), monopolar diathermy (Mono), and bipolar scissors (Bi). Laparoscopy was performed under general anesthesia in pigs, and the mesentery was dissected using each energy device. Tissue temperature at a distance of 1 mm from the energy device blade before and after dissection was measured. Temperature of the device blade both before and after dissection, time required for dissection, and interval until the temperature fell to 100°C, 75°C, and 50°C were documented. Results: Temperature of the surrounding tissue using each device rose the most with the Mono (50.5±8.0°C) and the least with the HS in full mode (6.2±0.7°C). Device temperature itself rose the highest with the AU in full mode (318.2±49.6°C), and the least with the Bi (61.9±4.8°C). All ultrasonic coagulation and cutting devices (AU, SS, and HS) had device temperatures increase up to ≥100°C, and even at 8 seconds after completing dissection, temperatures remained at ≥100°C. Conclusions: Because the adjacent tissue temperature peaked with the Mono, cautious use near the intestine and blood vessels is necessary. In addition, the active blades of all ultrasonic coagulation and cutting devices, regardless of model, developed high temperatures exceeding 100°C. Therefore, an adequate cooling period after using these devices is therefore necessary between applications.

Comparison of anchoring capacity of mesh fixation devices in ventral hernia surgery.

Background A reliable method of fixation of intraperitoneal mesh is required both in laparoscopic and open surgery for ventral hernia. We evaluated anchoring capacity of 3 fixation devices available for clinical use. Materials and Methods Anchoring capacity of 3 commercially available fixation devices were compared by counting the number of sheets anchored by a single firing under a fixed pressure. A total of 5 trials were conducted for each device. Results The number of sheets fixed (mean±SD) were, 12.4±1.1 for a coil type; 11.4±1.3 for a helical type; and 5.8±0.5 for a staple type tacker. The fixation capacity of the staple type was significantly lower than the other 2 types (P<0.0001). However, there was not statistically significant difference between the coil type and the helical type tackers. Conclusions The helical and coil type tackers in ventral hernia equally provide deep penetration that may contribute to strong fixation of the intraperitoneal mesh to the abdominal wall.

Standardization of surgical procedures to reduce risk of anastomotic leakage, reoperation, and surgical site infection in colorectal cancer surgery: a retrospective cohort study of 1189 patients

PurposeAnastomotic leakage (AL) and surgical site infection (SSI) are prevalent complications of colorectal surgery. To lower this risk, we standardized our surgical procedures in 2012, with a preferential use of laparoscopic approach (LS) for both colon and rectal surgery, combined with triangulating anastomosis (TA) for colon surgery and defunctioning ileostomy (DI) for low anterior resection. Our aim was to evaluate the outcomes of our standardized procedures.MethodsThe incidence rate of AL (primary outcome) and of reoperation and SSI (secondary outcome) was compared before (early period, n = 648) and after (late period, n = 541) standardization, through a retrospective analysis.ResultsThe incidence rate of AL (6.6 versus 1.8%; P = 0.001), reoperation (3.5 versus 0.7%; P = 0.0012), and SSI (7.7 versus 4.6%; P = 0.029) was lower in late than in the early period. For colon cancer, TA and LS reduced the risk of AL (2.1 versus 0.3%, P = 0.020, for TA, and 3.2 versus 0.4%, P = 0.0027, for LS) and reoperation (2.9 versus 0.3%, P = 0.003, for TA, and 2.5 versus 0.2%, P = 0.0040, for LS). For rectal cancer, the incidence of all adverse outcomes (AL, reoperation, and SSI) was lower in cases treated by LS. However, the incidence of AL was lower in the late than in early period (P = 0.002) and with LS (P = 0.002). On multivariate analysis, late period and LS were independent factors of a lower risk of adverse outcomes.ConclusionsOur surgical standardization seems to be effective in lowering the risks of AL, reoperation, and SSI after colorectal cancer surgery.