Search

Background Postoperative pancreatic fistula (POPF) is a life-threatening postoperative complication. The aim of this study was to evaluate the efficacy of the fistula risk score (FRS) and preoperative body composition factors for predicting the occurrence of clinically relevant POPF (CR-POPF) after pancreaticoduodenectomy (PD). Methods In this study, 136 consecutive patients who underwent PD between 2006 and 2018 were enrolled. The risk factors of CR-POPF (grades B and C) were analyzed. Preoperative visceral adipose tissue area (VATA), skeletal mass index (SMI), and subcutaneous adipose tissue area (SATA) were calculated from computed tomography data. Results The overall 30-day mortality and morbidity rates were 0.7 and 38%, respectively. The incidence rates of grade B and C CR-POPF were 27 and 4%, respectively. A univariate analysis revealed that male sex, habitual smoking, prognostic nutritional index (PNI) 4 were significantly associated with the incidence of CR-POPF. A multivariate analysis revealed that PNI 4 were the independent risk factors of CR-POPF. Conclusions Preoperative anthropomorphic imbalance, PNI, and FRS were independent risk factors for CR-POPF. Patients with high-risk factors should be closely monitored during the postoperative period.

Background: Nivolumab has been approved for recurrent or metastatic head and neck cancer (R/M HNC) on March 2017 in Japan. Recently, many researchers have been actively studying the prognostic and ...

Purpose The number of patients on antiplatelet therapy (APT) who need surgery is increasing; however, it is unclear whether APT should be continued for abdominal surgery, particularly laparoscopic colorectal surgery. We investigated the safety of continuing APT for patients undergoing laparoscopic colorectal surgery. Methods We collected retrospective data from 529 patients who underwent laparoscopic colorectal surgery at Hiroshima University between January, 2013 and December, 2018. We analyzed information related to APT. Thirty-six pairs were matched by the propensity score method between patients on APT (APT+) and those not on APT (APT−). We compared the surgical outcomes of both groups. Results Among 463 patients eligible for the study, 48 were on APT for cerebrovascular or cardiovascular disease, and 36 continued to take aspirin. In the case-matched comparison, the amount of intraoperative blood loss in the APT+ group was not significantly higher than that in the APT− group, and the incidences of bleeding complications, thromboembolic complications, and other complications were not significantly different between the groups. Conclusion In a case-matched comparison, continuation of aspirin during laparoscopic colorectal surgery did not increase perioperative complications. In laparoscopic colorectal surgery, continuation of aspirin is an acceptable strategy for patients with thromboembolic risk caused by interruption of APT.

Acute peritonitis has remained a fatal disease despite of recent advances in care and treatment, including antibiotic and anticoagulant treatments. The cause of death is mostly sepsis-induced multiple organ failure. Oxidative stress can play an important role in this situation, but antioxidant therapy to capture any excessive reactive oxygen species has not yet been fully established.Two experiments were performed. In the first experiment, we confirmed the effects of peritoneal lavage with hydrogen-rich saline (HRS) after a cecal ligation and puncture (CLP) operation in rats. In the second experiment, the changes in the hemodynamic state following this procedure were observed in a porcine model of abdominal sepsis to evaluate its safety and utility.Peritoneal lavage with HRS significantly improved the survival after CLP in rats, and it ameliorated the levels of sepsis-induced organ failure. Moreover, it showed anti-inflammatory and anti-apoptosis as well as antioxidant effects. The second experiment demonstrated the potential safety and feasibility of this procedure in a large animal model.This procedure can improve survival after sepsis through mitigating the sepsis-induced organ failure by inhibiting oxidative stress, apoptosis, and inflammatory pathways. Peritoneal lavage with HRS may therefore be an effective, safe, and practical therapy for patients with acute peritonitis.

Background This study aimed to assess the prognostic factors including low skeletal muscle mass index (SMI) and perioperative blood transfusion for patients with hepatocellular carcinoma (HCC) following curative surgery. Methods This study included 139 patients with HCC who underwent hepatectomy between 2005 and 2016. Univariate and multivariate analyses were performed to identify variables associated with overall survival (OS) and recurrence-free survival (RFS). Results Low SMI was significantly related with poor OS, while blood transfusion had a strong impact on RFS. The male ratio and body mass index in the low SMI group were significantly higher than those in the high SMI group. There were no significant differences in age, virus etiology, laboratory data, liver function, tumor makers, and operative variables between the groups. Tumor factors such as tumor diameter, tumor number, poor differentiation, and intrahepatic metastasis (IM) did not significantly differ between the two groups. Operation time, intraoperative blood loss volume, and recurrence ratio were significantly higher in the blood transfusion group than in the non-transfusion group. IM was associated with poor OS and RFS. Conclusions Low SMI and blood transfusion were independently related with long-term prognosis in patients with HCC following curative surgery.

Laparoscopic surgery for colorectal cancer, not only early cancer but also advanced cancer, has become standardized by some randomized controlled studies. However, cases involving advanced transverse colon cancer were excluded from these studies due to the technical difficulty of the surgery. Hence, laparoscopic surgery for advanced transverse colon cancer is still a theme that we need to overcome. To solve these issues, it is necessary to establish a standardized approach and surgical technique. The advantage of our method, which approaches from both sides of the transverse mesocolon, is that it is easier to achieve hemostasis when active bleeding occurs because this approach provides space for ligating and sealing. This allows the surgeon to perform lymphadenectomy around the superior mesenteric artery and vein. We introduced the usefulness of the “Pincer approach of the transverse mesocolon” to standardize laparoscopic surgery for advanced transverse colon cancer.

The performance of endoscopic surgery has quickly become widespread as a minimally invasive therapy. However, complications still occur due to technical difficulties. In the present study, we focused on the problem of blind spots, which is one of the several problems that occur during endoscopic surgery and developed “BirdView,” a camera system with a wide field of view, with SHARP Corporation. In the present study, we conducted a clinical trial (Phase I) to confirm the safety and usefulness of the BirdView camera system. We herein report the results. In this study, surgical adverse events were reported in 2 cases (problems with ileus and urination). There were no cases of device failure, damage to the surrounding organs, or mortality. We evaluated the safety of the BirdView camera system. We believe that this camera system will contribute to the performance safe endoscopic surgery and the execution of robotic surgery, in which operators do not have the benefit of tactile feedback.

The image quality and performance of 3-dimensional video image systems has improved along with improvements in technology. However, objective evaluation on the usefulness of 3-dimensional video image systems is insufficient. Therefore, we decided to investigate the usefulness of 3-dimensional video image systems using the objective endoscopic surgery technology evaluating apparatus that we have developed, the Hiroshima University Endoscopic Surgical Assessment Device (HUESAD). The participants were 28 student volunteers enrolled in Hiroshima University (17 men and 11 women, age: median 22.5, range 20–25), with no one having experienced endoscopic surgery training. Testing was carried out by dividing the subjects into two groups to initially carry out HUESAD with 2-dimensional video imaging (N = 14) and with 3-dimensional video imaging (N = 14). Questionnaires were carried out along with the investigation regarding both 2-dimensional and 3-dimensional video imaging. The task was carried out for approximately 15 min regarding both 2-dimensional and 3-dimensional video imaging. Lastly, the Mental Rotation Test, which is a standard space perception ability test, was used to evaluate the space perception ability. No difference was observed in the nauseous and uncomfortable feeling of practitioners between the two groups. Regarding smoothness, no difference was observed between 2-dimensional and 3-dimensional video imaging (p = 0.8665). Deviation (space perception ability) and approaching time (accuracy) were significantly lower with 3-dimensional video imaging compared to 2-dimensional video imaging. Moreover, the approaching time (accuracy) significantly improved in 3-dimensional video imaging compared to 2-dimensional video imaging in the group with low space perception ability (p = 0.0085). Objective evaluation using HUESAD and subjective evaluation by questionnaire revealed that endoscopic surgery techniques significantly improved in 3-dimensional video imaging compared to 2-dimensional video imaging. Moreover, it is believed that this effect is more effective in people with low space perception ability and beginner students.

Aim This study aimed to investigate the clinicopathological predictors of survival in patients with intrahepatic cholangiocarcinoma, mass-forming type (ICC-MF), following curative intent hepatectomy. Methods Clinical characteristics and outcomes were analyzed in a series of 42 patients who underwent curative hepatectomy for ICC-MF between February 1987 and December 2012. The relationship between immunohistochemical expression profiles of mucin (MUC) core proteins (MUC2, MUC5AC, and MUC6) and surgical outcomes was examined. Results The overall median follow-up period was 2.6 years (0.2–17.9). Bile duct reconstruction ( p = 0.017), lymph node metastasis ( p = 0.049), maximal mass diameter ≥5.0 cm ( p = 0.002), and MUC5AC expression ( p = 0.003) were identified as significant adverse predictors of overall survival by univariate analysis. Bile duct reconstruction ( p = 0.048), maximal mass diameter ≥5.0 cm ( p = 0.002), and MUC5AC expression ( p = 0.005) were found to be independent predictors of poor prognosis by multivariate analysis. Maximal mass diameter ≥5.0 cm ( p = 0.011) was found to be an independent predictor for the tumor recurrence. There was a strong correlation between MUC5AC expression and lymph node metastasis ( p = 0.021). MUC6 expression was more frequent in patients with concurrent MUC5AC expression ( p = 0.019). Conclusions MUC5AC expression was significantly related to long-term prognosis and aggressive tumor development, and may be a useful prognostic marker.

The optimal prognostic predictive system for gallbladder carcinoma (GBC) has not been established. The gallbladder cancer predictive risk score (GBRS) based on pathological findings identifies incidental GBC patients at risk of recurrence. We aimed to validate the prognostic ability of the GBRS in all GBC patients following curative surgery. Fifty-six patients with GBC who underwent curative surgery between 1996 and 2016 were included in this study. Univariate and multivariate analyses were performed to determine prognostic factors associated with overall and recurrence-free survival, and propensity score-matched analysis was performed. The median patient age was 71.9 years, and 39.3% of patients were males. All patients underwent curative surgery (33.9%, simple cholecystectomy; 66.1%, more advanced procedures, such as hepatectomy; and 32.1%, bile duct reconstruction). On univariate analysis, preoperative carbohydrate antigen 19-9 (CA19–9) ≥ 37 U/mL (p = 0.042), postoperative complications (p = 0.043), and a high GBRS (p

In surgery for elderly patients with colorectal cancer, it is unclear whether radical lymph node (LN) dissection safely offers a survival benefit. The aim of the study was to evaluate the impact of the LN yield in elderly patients undergoing surgery for colorectal cancer.The subjects were selected from a surgical database of 2065 patients aged ≥80 years old who underwent surgery for colorectal cancer at 41 hospitals in Japan between 2003 and 2007. The patients were divided into groups according to the number LN harvested:12 and ≥12. Propensity scores were subsequently matched to balance the baseline characteristics.Of the 954 patients initially selected, 331 were in the12 LN and 623 were in the ≥12 LN group. After cases were matched, 293 patients were allocated to each group, and all covariates were balanced. For short-term outcomes, the time for surgery was longer in the ≥12 LN group, but there was no significant difference in morbidity between the groups. Overall, relapse-free and cancer-specific survival rates were higher in the ≥12 LN group (P = 0.004, 0.001, and 0.02).In patients aged ≥80 years old with stage II-III colon cancer, harvesting ≥12 LN provides a survival benefit, and therefore, limited LN dissection is not recommended in these patients.

BACKGROUND/AIM Perioperative red blood cell transfusion (RBCT) can negatively affect the host's immune system. We investigated the effects of perioperative RBCT on long-term survival among patients with pancreatic ductal adenocarcinoma (PDAC). PATIENTS AND METHODS We retrospectively evaluated 148 patients with PDAC who underwent surgery with curative intent (33 who received RBCTs and 115 who did not). Significant prognostic variables on univariate analysis were subjected to multivariate analyses using a Cox proportional hazard regression model. RESULTS Both groups exhibited significant differences in age, preoperative haemoglobin levels, carbohydrate antigen 19-9 levels, maximum tumour size, tumour staging, operative time, intraoperative blood loss, major vascular resection, and the proportion of pancreaticoduodenectomies performed. Patients who underwent RBCTs exhibited significantly poorer overall survival (p

Systemic inflammation can promote tumor growth. The Glasgow Prognostic Score (GPS), a simple assessment of systemic inflammation status, could be useful to predict the prognosis of hepatocellular carcinoma (HCC) patients after hepatectomy. Consecutive HCC patients were enrolled following hepatectomy at our institution between 2005 and 2012. Univariate and multivariate analyses were performed to identify variables associated with overall survival (OS) and recurrence-free survival. Patients were stratified according to the GPS. To minimize selection bias, propensity score analysis was performed. An elevated GPS (1–2), des-gamma carboxyprothrombin levels (≥40 mAU/mL), and the presence of multiple tumors were significantly associated with a poor OS. Alpha-fetoprotein levels (≥20.0 ng/mL), des-gamma carboxyprothrombin levels (≥40 mAU/mL), and the presence of multiple tumors were independent risk factors for a poor recurrence-free survival. After one-to-one matching, 92 patients each with a normal GPS (0) and an elevated GPS (1–2) had similar preoperative and operative characteristics. Poorer OS times in patients with an elevated GPS were confirmed by excluding possible misinterpretation. An elevated GPS was an independent prognostic indicator for OS after hepatectomy in HCC patients. The GPS, which employs inexpensive and readily available biomarkers, could be a novel tool for predicting survival in such patients.

Few studies have investigated the risk factors in patients with peritoneal carcinomatosis (PC) from colorectal cancer (CRC) who die within 3 months of undergoing surgical intervention and systemic chemotherapy. This study aimed to identify the risk factors associated with the post-treatment 3-month mortality rate. Retrospectively collected data from Hiroshima University were analyzed for patients presenting with synchronous PC from CRC between 1992 and 2012. The clinical, histological and survival data were evaluated and correlated with the overall survival rate at 3 months after surgical intervention. In patients who underwent surgical intervention with systemic chemotherapy for synchronous PC from CRC (N = 65), a Kaplan–Meier analysis and the log-rank test revealed that systemic chemotherapy (P = 0.023) and the modified Glasgow Prognostic Score (mGPS) (P = 0.00001) were associated with the 3-month mortality rate. Multivariate analyses using these two factors revealed that the mGPS (0/1, 2) (odds ratio 8.087; 95 % CI 1.512–43.25; P = 0.015) was an independent risk factor for the 3-month mortality rate. The mGPS is an important independent predictor of the 3-month mortality rate in patients who undergo surgical intervention with systemic chemotherapy for synchronous PC from CRC. The mGPS could aid surgeons in choosing the appropriate treatment strategy and best care for patients.

In this study, we present electroencephalographic (EEG) recording data obtained in correlation with timing behavior in rats trained in a 30-s peak interval (PI) procedure. The distribution of lever press responses was found to be Gaussian, peaking at approximately 30 s: lever pressing behavior increased for 30 s then decreased after the reinforcement time. We recorded EEG activity in the hippocampus (hippocampal theta wave) and striatum during the task, and evaluated whether the EEG power correlated with the behavior pattern. We found that the striatum EEG, but not the hippocampal theta wave, showed a good correlation with the response pattern in the 30-s PI. This result suggests that striatum neurons fired more synchronously at the time of reinforcement, thus supporting a critical role for synchronization of firing of striatal neurons in regulating timing mechanisms. This article is part of a Special Issue entitled: Associative and Temporal Learning.

The hippocampus is important in learning during a discrimination-reversal task. In this task, animals first learn to emit the go response to one stimulus and the no-go response to another stimulus (S1+, S2−) during the discrimination phase, and then they learn to reverse these relationships between stimulus and response during the reversal phase (S1−, S2+). To emit a no-go response for non-reinforced trial during the reversal phase, animals needed to inhibit the previously learned response pattern. This study examined the relationship between the reversal phase of the discrimination-reversal task and hippocampal electric activity in operant conditioning. The results revealed that hippocampal theta power transiently declined during the non-reinforced trial in the reversal phase compared with that during the discrimination phase. This decrease was observed during the 400–600-ms epoch after the onset of stimulus presentation. This study suggested that transient decline in hippocampal theta power is related to negative memory retrieval.

This study examined hippocampal theta power during configural and non-configural tasks in rats. Experiment 1 compared hippocampal theta power during a negative patterning task (A+, B+, AB-) to a configural task and a simple discrimination task (A+, B-) as a non-configural task. The results showed that hippocampal theta power during the non-reinforcement trial (non-RFT) of the negative patterning task was higher than that during the simple discrimination task. However, this hippocampal power may reflect sensory processing for compound stimuli that have cross-modality features (the non-RFT of the negative patterning task was presented together with visual and auditory stimuli, but the non-RFT of the simple discrimination task was presented with visual or auditory stimulus alone). Thus, in experiment 2, we examined whether the experiment 1 results were attributable to sensory processing of a compound stimulus by comparing hippocampal theta power during negative patterning (A+, B+, AB-), simultaneous feature-negative (A+, AB-), and simple discrimination tasks (A+, B-). Experiment 2 showed that hippocampal theta activity during the non-RFT in the negative patterning task was higher than that in the simultaneous feature-negative and simple discrimination tasks. Thus, we showed that hippocampal theta activity increased during configural tasks but not during non-configural tasks.

The aim of our study is to assess the impact of skill in laparoscopic surgery on the learning of robot-assisted surgery by urologic surgeons using the Mimic dV-trainer (MdVT).Twenty-three urologic surgeons using the MdVT were assessed. Ten of them were laparoscopic surgeons certified by the Japanese Society of Endourology. Each of the subjects completed four trials of a program consisting of four EndoWrist modules and two needle-driving modules. The performances of all subjects were recorded using a built-in scoring algorithm.In only one of the needle-driving tasks, Suture Sponge (that all subjects felt was the most difficult task), the scores of the certified laparoscopic surgeons became significantly better than those of the other subjects at the 2nd and the 3rd trials (p=0.0236 and p=0.0043 at the 2nd and 3rd trials, respectively). At the 4th trial there was no significant difference between the two groups with regard to the overall scores of any tasks.Our data indicate that familiarity with laparoscopic surgery is not associated with any advantage in learning the most fundamental techniques of robot-assisted surgery.

Background Laparoscopic surgery has spread quickly during the past twenty years, and has become one of the important treatments in the field of colorectal surgery. Recently, natural orifice transluminal endoscopic surgery (NOTES) has been studied as the next generation of minimally-invasive surgery, but the feasibility and safety of the NOTES method have not been evaluated. In such a situation, single-incision laparoscopic surgery has attracted interest from surgeons worldwide. However, single-incision laparoscopic colorectal surgery has not yet been standardized. Methods From February 2010, single-incision laparoscopic colectomy was performed for 7 patients presenting with early colon cancer. All procedures were performed by two experts with the License of Endoscopic Surgical Skill Qualification System (ESSQS) of Japan Society for Endoscopic Surgery (JSES) in the field of colorectal Surgery. Results We used the Gelport system (Applied Medical, Rancho Santa Margarita, CA, USA) as the access port and 3 trocars of different sizes (Ethicon, Inc., Cincinnati, OH, USA). Using this technique, we did not experience any difficulties or use any articulated instruments. All of the present 7 patients underwent the single-incision laparoscopic colectomy successfully and had no complications. Conclusion: Single-incision laparoscopic surgery using the Gelport was performed safely in the present cases. The use of the Gelport as an access port can address the technical difficulty associated with this new technique.

Neuroactive steroids are synthesized in the central and peripheral nervous systems. The purpose of this study was to analyze the effects of environmental enrichment on neuroactive steroidogenesis in the rat hippocampus. Environmental enrichment rats were housed in a group of nine in a large cage and three groups of pair-housed rats were housed in a standard cage for 8 weeks. The levels of mRNAs for steroidogenic enzymes and proteins in hippocampus were quantified by real-time RT-PCR. Environmental enrichment increased the mRNA expression levels of 5α-reductase-1 and 3α-hydroxysteroid dehydrogenase, which catalyze synthesis of allopregnanolone from progesterone. Hence, environmental enrichment appears to affect allopregnanolone synthesis.

The purpose of this study was to investigate whether the rat P3-like potential reflects "attention processes" rather than "arousal level". After controlling for arousal levels, event-related potentials (ERPs) of the rat were recorded at the anterior cingulate cortex and hippocampal CA1 during active and passive oddball paradigms. The arousal level of the passive group was equivalent to that of the active group, while the amplitude of the P3-like potential during the active paradigm was greater than that during the passive paradigm for both sites. These results provide evidence that the rat P3-like component reflects "attention processes", which is also the case for the human P3 component. Rats can provide a useful model for investigation of the neural mechanisms of the P3 in humans.

Background Although previous studies have demonstrated the needs for a spatial cognitive ability that can give an accurate understanding of the position, orientation, and size and form of the objects in endoscopic surgery, there has been no study on the relationship between the skills of robot-assisted surgery and spatial cognitive ability. Objective To assess the effect of spatial cognitive ability on gain in robot-assisted surgical skills of urological surgeons. Materials and Methods The robot-assisted surgery skills of 24 urological surgeons who had no previous experience with the Mimic dV-Trainer (MdVT) and had not been the main surgeon in robot-assisted surgery and 20 volunteer medical students who had no previous experience of the MdVT were assessed by using a program consisting of 4 kinds of tasks. Their performances were recorded using a built-in scoring algorithm. Their spatial cognitive abilities were also assessed using a mental rotation test. Results Although there was a significant correlation between the spatial cognitive ability and a score of 2 for the more difficult tasks for student groups using the MdVT, there was no significant correlation between them for all tasks for groups of urological surgeons. Conclusion The results of the present study indicate that differences in spatial cognitive ability in urological surgeons have no effect on the gain in fundamental robot-assisted surgery skills whereas there was a significant correlation between the spatial cognitive ability and fundamental robot-assisted surgical skills in the volunteers.

Background/Aims: Liver transplantation (LT) is promising method of treatment for hepatocellular carcinoma (HCC) patients, but is limited by donor organ shortages and tumor progression during long wait periods. This study investigated the efficacy of salvage living donor LT (LDLT) after initial liver resection (LR) in HCC patients. Methods: Sixty patients with HCC who underwent primary LDLT (n = 45) or salvage LDLT after initial LR (n = 15) were enrolled. Significant prognostic variables determined by univariate analysis were subjected to multivariate analysis using a Cox proportional hazard regression model. Cox proportional hazards models with inverse probability of treatment weighting (IPTW) based on propensity score were used to adjust for selection bias between groups. Results: The salvage group had significantly higher Child-Pugh class A (p = 0.003), ≥3 pretransplant treatments (p = 0.007), and reoperation rates for postoperative bleeding (p = 0.032) than the primary LDLT group, whereas overall and recurrence-free survival rates were comparable. After IPTW matching, the salvage LDLT group had significantly more reoperations for postoperative bleeding (hazard ratio 7.948, p = 0.017). Conclusions: First-line LR followed by salvage LDLT allows survival equal to that of primary LDLT. Salvage LDLT following primary LR could be an effective therapy.

One of the disadvantages of laparoscopic surgery is its decreased tactile feedback. Surgical experience compensates for the decline in the sense of touch due to an improved ability to process visual information. Stochastic resonance (SR) is known to improve tactile sensation. In this study, we sought to improve the tactile feedback in laparoscopic surgery using SR to safely perform laparoscopic surgery. Ten surgeons (nine males and one female, age: 30–44 years, median age: 34) with the experiences of >50 laparoscopic surgeries volunteered to participate in this study. We tested the hypothesis that low-level noise applied to the hand can enhance the tactile sensation during surgery. We performed this experiment under three hand conditions (bare-handed conditions, gloved conditions and using the laparoscopic instrument with gloved hands). A piezoelectric actuator that generates vibrations was attached on the radial side of the participant’s index finger or to the grip of the laparoscopic instrument. Fine-touch tests were performed using the Semmes–Weinstein test kit. Moreover, we planned laparoscopic suturing and knot-tying tasks in the dry box and using an animal model under controlled vibrations. In the touch tests using bare hands, gloved hands and the laparoscopic instrument, the mean correct ratio was significantly lower than that observed in the test with no vibrations. Moreover, the OSATS scores for the laparoscopic suturing and knot-tying tasks showed significantly better scores with vibrations. This technique has a potential to be a great help in establishing safer and high-quality laparoscopic procedures.

Hippocampal functions are influenced by steroid hormones, such as testosterone and estradiol. It has been demonstrated that hippocampus-derived steroid hormones play important roles in neuronal protection and synapse formation. Our research groups have demonstrated that estradiol is de novo synthesized in the rat hippocampus. However, the mechanism(s) regulating this synthesis remains unclear. It has been reported that tributyltin, an environmental pollutant, binds to the retinoid X receptor (RXR) and modifies estrogen synthesis in human granulosa-like tumor cells. This compound can penetrate the blood brain barrier, and tends to accumulate in the brain. Based on these facts, we hypothesized that tributyltin could influence the hippocampal estradiol synthesis. A concentration of 0.1 μM tributyltin induced an increase in the mRNA content of P450(17α) and P450arom in hippocampal slices, as determined using real-time PCR. The transcript levels of other steroidogenic enzymes and a steroidogenic acute regulatory protein were not affected. The estradiol level in rat hippocampal slices was subsequently determined using a radioimmunoassay. We found that the estradiol synthesis was stimulated by ∼2-fold following a 48-h treatment with 0.1 μM tributyltin, and this was accompanied by transcriptional activation of P450(17α) and P450arom. Tributyltin stimulated de novo hippocampal estradiol synthesis by modifying the transcription of specific steroidogenic enzymes.

Robot-assisted surgery using the da Vinci Surgical System provides three-dimensional images. However, no research has yet been done on the relationship between the system’s operation and spatial cognitive ability. This study focuses on the operator’s spatial cognitive ability which can impact acquisition of the skills required to operate the da Vinci Surgical System. The participants of the study were 20 volunteers who were students at Hiroshima University (9 men and 11 women, average age 21.1 ± 1.6 years). Depending on the mental rotation test’s score the participants were divided into two groups, one with High group (n = 10), and the other with Low group (n = 10). Both groups were tested using Hiroshima University endoscopic surgical assessment device (HUESAD) and the da Vinci Surgical System simulator dV-Trainer. HUESAD; No significant difference was noted between the two groups in terms of smoothness (p = 0.3867). In terms of accuracy and spatial cognitive ability, the High group scored significantly lower values than the Low group. dV-Trainer; In terms of overall Score, no significant difference was seen between the two groups (pick and place: p = 0.1639; peg board: p = 0.1883; thread the rings: p = 0.8928; suture sponge: p = 0.3238). This study indicates that differences in spatial cognitive ability have no impact at the initial stages to operate the da Vinci Surgical System. Despite this, it should be repeated that the da Vinci Surgical System is not something that facilitates simple surgery that can be implemented by anyone.

The safety of laparoscopic surgery (LAP) in elderly patients with colorectal cancer has not been demonstrated. The aim of this study was to compare the outcomes of LAP and open surgery (OP) and estimate the feasibility of LAP in colorectal cancer patients aged ≥80 years. We conducted a propensity scoring matched case–control study of colon and rectal cancer patients aged ≥80 years using data from 41 hospitals between 2003 and 2007. A total of 1,526 colon cancer patients and 282 rectal cancer patients underwent surgery and were included in the analysis. The primary end point was 3-year overall survival (OS). Secondary end points included disease-free survival (DFS), cancer-specific survival (CSS), and postoperative complications. LAP and OP were compared in 804 colon cancer patients (402 pairs) and 114 rectal cancer patients (57 pairs) after all covariates were balanced, and no significant differences were observed, except for tumor size in colon cancer. OS, DFS, and CSS did not differ between the groups for either colon cancer (P = 0.916, 0.968, and 0.799, respectively) or rectal cancer (P = 0.765, 0.519, and 0.950, respectively). In colon cancer cases, LAP was associated with fewer morbidities than was OP (24.9 vs. 36.3 %, P

This paper reports experimental results on a surgical grasping forceps with a vibration actuator that enhances a tactile perception ability. A short-time exposure of tactile receptors to sub-sensory white-noise vibration is known to improve perception ability. This phenomenon, called stochastic resonance (SR) in the somatosensory system, is expected to enhance the sense of touch when the weak vibration is applied to a fingertip, and thereby improve associated motor skills. A lead zirconate titanate (PZT) actuator was attached on the grip of surgical grasping forceps. A passive sensory test has been conducted for healthy subjects to confirm the efficacy of the device. Statistical significance has been observed when appropriate noise is applied. To investigate the effect of the noise intensity, a summing network of FitzHugh-Nagumo model neurons was built. The simulation results showed that a network with relatively large units can improve the detection capability of the input signal.

This study examined configural association theory and conflict resolution models in relation to hippocampal neural activity during positive patterning tasks. According to configural association theory, the hippocampus is important for responses to compound stimuli in positive patterning tasks. In contrast, according to the conflict resolution model, the hippocampus is important for responses to single stimuli in positive patterning tasks. We hypothesized that if configural association theory is applicable, and not the conflict resolution model, the hippocampal theta power should be increased when compound stimuli are presented. If, on the other hand, the conflict resolution model is applicable, but not configural association theory, then the hippocampal theta power should be increased when single stimuli are presented. If both models are valid and applicable in the positive patterning task, we predict that the hippocampal theta power should be increased by presentation of both compound and single stimuli during the positive patterning task. To examine our hypotheses, we measured hippocampal theta power in rats during a positive patterning task. The results showed that hippocampal theta power increased during the presentation of a single stimulus, but did not increase during the presentation of a compound stimulus. This finding suggests that the conflict resolution model is more applicable than the configural association theory for describing neural activity during positive patterning tasks.

The hippocampus is essentially involved in learning and memory processes. Its functions are affected by various neuromodulators, including 17β-estradiol, testosterone, and retinoid. Brain-synthesized steroid hormones act as autocrine and paracrine modulators. The regulatory mechanism underlying brain steroidogenesis has not been fully elucidated. Synthesis of sex steroids in the gonads is stimulated by retinoic acids. Therefore, we examined the effects of retinoic acids on estradiol and testosterone biosynthesis in the rat hippocampus. We used cultured hippocampal slices from 10- to 12-d-old male rats to investigate de novo steroidogenesis. The infant rat hippocampus possesses mRNAs for steroidogenic enzymes and retinoid receptors. Slices were used after 24 h of preculture to obtain maximal steroidogenic activity because steroidogenesis in cultured slices decreases with time. The mRNA levels for P45017α, P450 aromatase and estrogen receptor-β in the slices were increased by treatment with 9-cis-retinoic acid but not by all-trans-isomer. The magnitude of stimulation and the shape of the dose-response curve for the mRNA level for P45017α were similar to those for cellular retinoid binding protein type 2, the transcription of which is activated by retinoid X receptor signaling. 9-cis-Retinoic acid also induced a 1.7-fold increase in the protein content of P45017α and a 2-fold increase in de novo synthesis of 17β-estradiol and testosterone. These steroids may be synthesized from a steroid precursor(s), such as pregnenolone or other steroids, or from cholesterol, as so-called neurosteroids. The stimulation of estradiol and testosterone synthesis by 9-cis-retinoic acid might be caused by activation of P45017α transcription via retinoid X receptor signaling.

17beta-estradiol is synthesized de novo in the rat hippocampus. However, the regulatory mechanism of hippocampal estradiol synthesis has remained unclear. We investigated the effects of social isolation on rat hippocampal estradiol synthesis. Rats were divided into two groups: social isolation and pair housed group. Socially isolated rats were housed individually while pair housed rats were housed two per cage for 8 weeks. Social isolation activated the transcription of neurosteroidogenic molecules, including steroidogenic acute regulatory protein (StAR) and CYP19 (cytochrome P450arom). These two molecules are involved in the regulatory step for steroidogenesis and final step of estradiol synthesis. In contrast, the mRNA levels were not affected in rat olfactory bulb. The hippocampal estradiol content was increased in accordance with the increased mRNA levels. The hippocampal estradiol content exhibited correlations with the StAR and P450arom mRNA levels. These data suggest that social isolation may enhance de novo estradiol synthesis in the hippocampus.

Background In stage IV colorectal cancer (CRC) with unresectable metastases, whether or not resection of the primary tumor should be indicated remains controversial. We aim to determine the impact of primary tumor resection on the survival of stage IV CRC patients with unresectable metastases. Methods We retrospectively investigated 103 CRC patients with stage IV colorectal cancer with metastases, treated at Hiroshima University Hospital between 2007 and 2013. Of these, those who had resectable primary tumor but unresectable metastases and received any chemotherapy were included in the study. We analyzed the overall survival (OS) and short-term outcomes between the patients who received up-front systemic chemotherapy (USC group) and those who received primary tumor resection followed by chemotherapy (PTR group). Results Of the 57 included patients, 15 underwent USC and 42 PTR. The median survival times were 13.4 and 23.9 months in the USC and PTR groups, respectively (P = 0.093), but multivariate analysis for the overall survival showed no significant difference between the two groups (hazard ratio, 1.30; 95% confidence interval (CI), 0.60 to 2.73, P = 0.495). In the USC group, the disease control rate of primary tumor was observed in 12 patients (80.0%), but emergency laparotomy was required for 1 patient. Morbidity in the PTR group was observed in 18 cases (42.9%). Conclusions The overall survival did not differ significantly between the USC and PTR groups. USC may help avoid unnecessary resection and consequently the high morbidity rate associated with primary tumor resection for stage IV CRC with unresectable metastases.

Background Single-port laparoscopic surgery is a new technique that leaves no visible scar. This new technique has generated strong interest among surgeons worldwide. However, single-port laparoscopic colon surgery has not yet been standardized. Our aim in this study was to evaluate the feasibility of single-port laparoscopic colectomy compared with conventional laparoscopic colectomy for colon cancer. Methods We conducted a case-matched, controlled study comparing single-port laparoscopic colectomy to conventional laparoscopic colectomy for right-sided colon cancer. Results A total of ten patients were included for the single-port laparoscopic colectomy (S-LAC) group and ten patients for the conventional laparoscopic colectomy (C-LAC) group. The length of the skin incision in the S-LAC group was significantly shorter than that of the C-LAC group. Conclusion Our early experiences indicated that S-LAC for right-sided colon cancer is a feasible and safe procedure and that S-LAC results in a better cosmetic outcome.

Background Robotic surgery is a new technique with the benefits of a three-dimensional view, the ability to use multi-degree-of-freedom forceps, the elimination of physiological tremors, and a stable camera view. The aim of this study was to evaluate the feasibility and short-term outcomes of robotic surgery for colorectal cancer as initial cases, compared with conventional laparoscopic surgery. Methods From July 2010 to June 2013, ten patients with left-sided colon and rectal cancer underwent robotic surgery, and 121 received conventional laparoscopic surgery. Both groups were balanced in terms of age, gender, American Society of Anesthesiologists (ASA) score, body mass index (BMI), operative history, TNM staging, and tumor location. Moreover, in order to improve objectivity and approximate a randomized controlled study, we used the propensity score matching method. The matching was successful because the ROC analysis showed a well-balanced curve (C = 0.535). Results Following propensity score matching, ten patients were included in the robotic surgery group and 20 patients were included in the conventional laparoscopic surgery group. There were no significant differences in the short-term clinicopathologic outcomes between the robotic surgery group and the conventional laparoscopic surgery group. However, the operative time was significantly longer in the robotic surgery group than in the conventional laparoscopic surgery group. Conclusions There were no significant differences between the robotic surgery group and the conventional laparoscopic surgery group with respect to short-term clinicopathologic outcomes, with the exception of the operative time. Our early experience indicates that robotic surgery is a promising tool, particularly in patients with rectal cancer. Electronic supplementary material The online version of this article (doi:10.1186/s12957-015-0517-6) contains supplementary material, which is available to authorized users.