Background
The first step toward increasing the level of patient safety in endoscopic surgery is for all endoscopic surgeons to acquire fundamental skills, including psychomotor skills, in the ...preoperation stage of training. The current study aimed to evaluate the effectiveness of virtual reality (VR) simulator training and box training for training the fundamental skills of endoscopic surgery.
Methods
For this study, 35 medical students at Kyushu University were divided into three groups: simulator (SIM) group (
n
= 20), box trainer (BOX) group (
n
= 20), and control group (
n
= 15). None of the students had any experience assisting with endoscopic surgery or any previous training for endoscopic surgery. The students in the SIM group underwent training using a VR simulator, the Procedicus MIST, 2 h per day for 2 days. The students in the BOX group underwent training using a box trainer 2 h per day for 2 days. The students in the control group watched an educational video for 30 min. The endoscopic surgical skills of all the students were evaluated before and after training with a task of suturing and knot tying using a box trainer.
Results
Although no significant differences were found between the three groups in the total time taken to complete the evaluation task before training, there were significant improvements in the SIM and BOX groups after training compared with the control group. Box training increased errors during the task, but simulator training did not.
Conclusion
The findings showed that box training and VR training have different outcomes. The authors expect that the best curriculum for their training center would involve a combination that uses the merits of both methods.
In a co-culture of osteoclast precursor cells and synovial cells, interleukin-6 (IL-6) induces osteoclast formation. In contrast, in a monoculture of osteoclast precursor cells, IL-6 directly ...suppresses receptor activator for nuclear factor κB ligand (RANKL)-induced differentiation of osteoclast precursor cells into osteoclasts. In the present study, we explored why the effect of IL-6 differed between the monoculture and the co-culture systems. In the monoculture, mouse osteoclast precursor cell line, RAW 264·7 (RAW) cells were cultured with soluble RANKL (sRANKL) for 24 h or 3 days. sRANKL increased both expression of osteoclastogenesis marker, tartrate-resistant acid phosphatase isoform 5b (TRAP5b) and nuclear factor of activated T cells cytoplasmic 1 (NFATc1), whereas the co-addition of IL-6 decreased them both in a dose-dependent manner. In the co-culture, RAW cells and human synovial cell line, SW982 cells were cultured with IL-6 + soluble IL-6 receptor (sIL-6R) for 3 days. TRAP5b and NFATc1 expression reduced by IL-6 was increased by the addition of SW982 cells in a manner dependent upon the number of added cells. IL-6 + sIL-6R treatment significantly induced RANKL production in SW982 cells, and anti-RANKL antibody inhibited IL-6 + sIL-6R-induced osteoclastogenesis. SW982 cells expressed high levels of ICAM-1 originally, and ICAM-1 expression was increased significantly by IL-6 + sIL-6R. Anti-ICAM-1 antibody suppressed IL-6-induced osteoclastogenesis. Finally, in the monoculture system, addition of sICAM-1 dose-dependently restored the expression of TRAP5b reduced by IL-6. Similar results were obtained when the formation of TRAP-positive multi-nuclear cells were examined using mouse bone marrow cells. In conclusion, IL-6 gave different results in the co-culture and monoculture systems because in the co-culture, ICAM-1 from the synovial cells restored osteoclastogenesis suppressed by IL-6.
We successfully fabricated a MnBi2Te4/Bi2Te3 heterostructure by incorporating Mn and Te inside the topmost quintuple layer of Bi2Te3, as unambiguously confirmed by low-energy electron diffraction I−V ...and scanning transmission electron microscopy measurements. The surface-state Dirac cone of the heterostructure showed little change compared to that of pristine Bi2Te3, and x-ray magnetic circular dichroism measurements showed that the system was paramagnetic down to 5.6 K. These results are in contrast to previous works on related materials that showed magnetic order around 10 K as well as theoretical predictions and suggest the intricacy of the magnetic properties of two-dimensional van der Waals magnets.
With the growth and sophistication of laparoscopic surgery, increased attention is now being focused on safety and complications.
In an attempt to address questions regarding the safety of ...laparoscopic surgery, a retrospective study of the time period from January 1991 to December 1995 was conducted by the Study Group of Endoscopic Surgery in Kyushu, Japan.
The response rate was 84.4% (152 of 180 hospitals). During the last 5 years 17,626 patients underwent endoscopic operations and 87.5% (15, 422 patients) had laparoscopic surgery while 12.5% (2,204 patients) underwent thoracoscopic surgery. In 96.6% of the hospitals a minimal open laparotomy was used. Among the various operations, a cholecystectomy was performed in the largest number of patients (13, 787). The total number of complications was 415 (2.7%), of which 156 (37.6%) were related to needle or trocar insertion. Visceral injury was found in 22 patients (0.14%): major vessel injury in 10, gastrointestinal tract injury in 11, and liver injury in one patient. Abdominal wall injury was seen in 79 patients (0.52%), bleeding in 70 (0.46%), and a hernia in 9 (0.06%). Extraperitoneal insufflation occurred in 55 patients (0.36%). There was no mortality. The complication rate significantly decreased year by year after the use of laparoscopic surgery began.
The most common complications of laparoscopic surgery are related to needle and trocar insertion. These are preventable by placement under direct vision with verification of the intraperitoneal location of the needle and trocar.
Modeling of the associations between mortality and air pollution data from 652 cities, mostly in the northern hemisphere, showed that concentrations of inhalable and fine particulate matter were ...associated with daily all-cause, cardiovascular, and respiratory mortality. An interactive map allows the reader to explore the geographic distribution of PM, and a Quick Take summarizes the findings in a short video.
Bone contouring is currently the best treatment for fibro-osseous lesions after bone growth arrest. Navigation systems available for this surgery allow intra-operative visualisation with improved ...cosmetic outcomes. However, conventional navigation systems using superficial skin registration cannot prevent subtle discrepancies.
To address this problem, we used a non-invasive cranial bone registration that uses patient-specific dental templates to maintain exact registration. We created the preset goal using the mirror image of the unaffected side for unilateral lesions, and using images obtained before the onset of symptoms for bilateral lesions. This system achieved precise pre-operative simulation. A sound aid in the navigation system provided information regarding proximity to critical structures and to the preset goal.
We used this system to contour fibro-osseous lesions in three patients. All patients achieved good facial contours and improvement in symptoms.
This method offers a safe, rapid surgical aid in treating orbital fibro-osseous lesions.
No reports exist on the role of laparoscopic hepatectomy in the short- and long-term outcomes of patients with hepatocellular carcinoma (HCC). We present our results from using laparoscopic ...hepatectomy for HCC and discuss the importance of this procedure.
To investigate the role of laparoscopic hepatectomy in the short- and long-term outcomes, 17 patients with HCC who underwent laparoscopic hepatectomy (laparoscopic hepatectomy group) were compared with 38 patients who underwent conventional open hepatectomy (open hepatectomy group) during the same period.
No differences in operation time, blood loss, rate of blood transfusion, or incidence of postoperative complications were found between the two groups. The postoperative hospital stay for the laparoscopic hepatectomy group was significantly shorter than for the open hepatectomy group. With long-term prognosis, no difference was found in survival rate and disease-free survival rate between the two groups. No recurrence was found in the stump of the remaining liver after laparoscopic hepatectomy.
Laparoscopic hepatectomy has resulted in a better short-term outcome after surgery than conventional open hepatectomy. The long-term prognosis in the laparoscopic hepatectomy group was similar to that in the open hepatectomy group. Therefore, laparoscopic hepatectomy can be a new alternative for treatment of cirrhotic patients with HCC when patients are strictly selected.
The reason for the large male predominance in the occurrence of hepatocellular carcinoma (HCC) remains unknown, and sex hormones may contribute to this phenomenon. We examined possible associations ...of serum levels of testosterone, free testosterone, estradiol, sex hormone binding globulin, and testosterone:estradiol ratio (T:E2 ratio) with HCC development in a follow-up study of 46 Japanese male patients with liver cirrhosis predominantly of hepatitis C virus origin (76%). Serum samples were collected between December 1985 and December 1987, and the patients were completely followed until the end of 1995 for an average of 5.1 years. During the follow-up period, 20 patients (43%) developed HCC. Univariate analysis demonstrated that serum T:E2 ratio and testosterone were significant predictors of HCC; the hazard ratios (and 95% confidence intervals) in the middle and upper tertiles relative to the lower tertile were 2.0 (0.5-7.6) and 4.0 (1.1-14.6; P trend = 0.03) for T:E2 ratio and 0.8 (0.2-3.1) and 2.9 (1.0-8.5; P trend = 0.05) for testosterone. Adjustment for age, serum albumin, hepatitis virus markers, and other clinicobiological variables substantially increased the corresponding hazard ratios. In multivariate analysis, serum free testosterone appeared to be associated with increased risk, yet independent associations with estradiol and sex hormone binding globulin were not evident. These results indicate that elevated serum testosterone, together with decreased serum estrogens, may promote the development of HCC in cirrhosis.
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