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In this paper, we are interested in the optimal investment and reinsurance strategies of an insurer who wishes to maximize the expected power utility of its terminal wealth on finite time horizon. We are also interested in the problem of maximizing the growth rate of expected power utility per unit time on the infinite time horizon. The risk process of the insurer is described by an approximation of the classical Cramér–Lundberg process. The insurer invests in a market consisting of a bank account and multiple risky assets. The mean returns of the risky assets depend linearly on economic factors that are formulated as the solutions of linear stochastic differential equations. With this setting, Hamilton–Jacobi–Bellman equations that are derived via a dynamic programming approach have explicit solution obtained by solving a matrix Riccati equation. Hence, the optimal investment and reinsurance strategies can be constructed explicitly. Finally, we present some numerical results related to properties of our optimal strategy and the ruin probability using the optimal strategy. [ABSTRACT FROM AUTHOR]

Purpose: Preoperative pain is known as one of the most powerful risk factors for chronic postoperative inguinal pain (CPIP), while its pathogenesis has not been fully elucidated. The aim of the present study was to evaluate patients with preoperative pain from the pathological perspective and discuss the potential pathogenesis of CPIP in those patients. Methods: This was a single-institutional retrospective study. The study population was inguinal hernia patients with preoperative pain who underwent open anterior hernia repair for primary inguinal hernia with pragmatic ilioinguinal neurectomy during surgery between March 2021 and March 2023. The primary and secondary outcomes were proportion of collagen deposition and mucus accumulation within ilioinguinal nerve in those patients, respectively, which were evaluated histologically using Image J software. Results: Forty patients were evaluated. Median value of proportion of intraneural collagen deposition was 38.3% (27.7–95.9). These values were positively correlated with the duration of pain (r2=0.468, P<0.001). Median value of proportion of mucus accumulation in ilioinguinal nerve was 50.1% (0–82.0). These values had no correlation with any clinicopathological variables. Conclusions: In the present study population, all patients with preoperative pain had intraneural fibrosis within ilioinguinal nerve, and its degree had a positive correlation with the pain duration. [ABSTRACT FROM AUTHOR]

Background: Despite growing evidence of the effectiveness of minimally invasive surgery (MIS) for primary gastric cancer, MIS for remnant gastric cancer (RGC) remains controversial due to the rarity of the disease. This study aimed to evaluate the surgical and oncological outcomes of MIS for radical resection of RGC. Patients and Methods: Patients with RGC who underwent surgery between 2005 and 2020 at 17 institutions were included, and a propensity score matching analysis was performed to compare the short- and long-term outcomes of MIS with open surgery. Results: A total of 327 patients were included in this study and 186 patients were analyzed after matching. The risk ratios for overall and severe complications were 0.76 [95% confidence interval (CI): 0.45, 1.27] and 0.65 (95% CI: 0.32, 1.29), respectively. The MIS group had significantly less blood loss [mean difference (MD), −409 mL; 95% CI: −538, −281] and a shorter hospital stay (MD, −6.5 days; 95% CI: −13.1, 0.1) than the open surgery group. The median follow-up duration of this cohort was 4.6 years, and the 3-year overall survival were 77.9% and 76.2% in the MIS and open surgery groups, respectively [hazard ratio (HR), 0.78; 95% CI: 0.45, 1.36]. The 3-year relapse-free survival were 71.9% and 62.2% in the MIS and open surgery groups, respectively (HR, 0.71; 95% CI: 0.44, 1.16). Conclusions: MIS for RGC showed favorable short- and long-term outcomes compared to open surgery. MIS is a promising option for radical surgery for RGC. [ABSTRACT FROM AUTHOR]

Background: The safety of robotic gastrectomy (RG) for gastric cancer in daily clinical settings and the process by which surgeons are introduced and taught RG remain unclear. This study aimed to evaluate the safety of RG in daily clinical practice and assess the learning process in surgeons introduced to RG. Methods: Patients who underwent RG for gastric cancer at Kyoto University and 12 affiliated hospitals across Japan from January 2017 to October 2019 were included. Any morbidity with a Clavien–Dindo classification grade of II or higher was evaluated. Moreover, the influence of the surgeon's accumulated RG experience on surgical outcomes and surgeon-reported postoperative fatigue were assessed. Results: A total of 336 patients were included in this study. No conversion to open or laparoscopic surgery and no in-hospital mortality were observed. Overall, 50 (14.9%) patients developed morbidity. During the study period, 14 surgeons were introduced to robotic procedures. The initial five cases had surprisingly lower incidence of morbidity compared to the following cases (odds ratio 0.29), although their operative time was longer (+ 74.2 min) and surgeon's fatigue scores were higher (+ 18.4 out of 100 in visual analog scale). Conclusions: RG was safely performed in actual clinical settings. Although the initial case series had longer operative time and promoted greater levels of surgeon fatigue compared to subsequent cases, our results suggested that RG had been introduced safely. [ABSTRACT FROM AUTHOR]

We are interested in problems related to forward starting options for Hull–White stochastic volatility model. Our objective is to obtain analytical, semi-analytical, or approximated expressions of its price for simulation. To obtain an analytical representation of the price, we use Yor's formula. However, the analytical formula is difficult to implement. Next we consider semi-analytical expressions for the price. In order to have them, we use the tower property for conditional expectations with a certain filtration and explicitly calculate it. Then, we consider an expansion expression for the price using the semi-analytical expression to have a simple expression. The semi-analytical expressions and the expansion expression can reduce computational costs and standard errors when the Monte Carlo method is used. Finally, some numerical results are given to show their accuracy and efficiency. [ABSTRACT FROM AUTHOR]

Background: Internal hernia (IH) is one of the critical complications after gastrectomy with Roux-en-Y reconstruction, which can be prevented by closing mesenteric defects. However, only few studies have investigated the incidence of IH after laparoscopic total gastrectomy (LTG) with Roux-en-Y reconstruction for gastric cancer till date. This study aimed to assess the efficacy of defect closure for the prevention of IH after LTG. Methods: This multicenter, retrospective cohort study collected data from 714 gastric cancer patients who underwent LTG with Rou-en-Y reconstruction between 2010 and 2016 in 13 hospitals. We evaluated the incidence of postoperative IH by comparing closure and non-closure groups of Petersen's defect, jejunojejunostomy mesenteric defect, and transverse mesenteric defect. Results: The closure group for Petersen's defect included 609 cases, while the non-closure group included 105 cases. The incidence of postoperative IH in the closure group for Petersen's defect was significantly lower than it was in the non-closure group (0.5% vs. 4.8%, p < 0.001). The closure group for jejunojejunostomy mesenteric defect included 641 cases, while the non-closure group included 73 cases. The incidence of postoperative IH in the closure group of jejunojejunostomy mesenteric defect was significantly lower than that in the non-closure group (0.8% vs. 4.1%, p = 0.004). Out of 714 patients, 41 underwent retro-colic reconstruction. No patients in the transverse mesenteric defect group developed IH. Conclusion: Mesenteric defect closure after LTG with Roux-en-Y reconstruction may reduce postoperative IH incidence. Endoscopic surgeons should take great care to prevent IH by closing mesenteric defects. [ABSTRACT FROM AUTHOR]

Background and Objective: Although older patients with coronavirus disease 2019 (COVID-19) are at the high risk of exacerbation that requires treatment with remdesivir, the safety of this medication is unclear in clinical practice, especially among older patients. We aimed to retrospectively evaluate the safety of remdesivir in older patients with COVID-19 who required hospitalization in our institute. Methods: We reviewed patients with COVID-19 who were treated with remdesivir at our institute between July 2020 and May 2021. We defined older patients as those aged 80 years or older at admission; all other patients were defined as younger patients. We evaluated the safety of remdesivir by examining the incidence of discontinuation of remdesivir treatment because of adverse events and the incidence of any adverse events. Results: A total of 80 patients were included in this study. Compared with younger patients, fewer older patients were treated with remdesivir for more than 5 days: 4 (15.4%) vs 23 (42.6%). Discontinuation of remdesivir because of adverse events occurred in one older patient (3.9%) and four younger patients (7.4%) [p > 0.99]. Remdesivir-induced liver dysfunction was the most frequent adverse event, which occurred in 29 (36.3%) patients. There were no significant differences in the incidence of remdesivir-induced liver dysfunction, renal dysfunction, and fatigue. Conclusions: The safety of remdesivir was suggested to be comparable between patients older than 80 years of age and patients younger than 80 years of age. The results of this study may encourage the administration of remdesivir to this older patient group. [ABSTRACT FROM AUTHOR]

Baseline cerebral regional saturation (rSO2) measured using the INVOS 5100C (Medtronic, MN, USA) varies widely among patients with cardiac and/or renal diseases. To identify significant correlates of baseline rSO2 and to investigate intraoperative rSO2 changes, we conducted a retrospective study in 494 patients undergoing on-pump cardiovascular surgery. Correlations between preoperative blood laboratory test variables and baseline rSO2 before anesthesia were examined. Intraoperative rSO2 changes were analyzed. Of all the variables examined, log-transformed B-type natriuretic peptide (BNP) most significantly and negatively correlated with baseline rSO2 (r = − 0.652, p < 0.0001). Intraoperatively, rSO2 showed the lowest value during cardiopulmonary bypass (CPB) (median rSO2: 56.2% during CPB vs. 63.9% at baseline, p < 0.0001). Although rSO2 during CPB correlated positively with hemoglobin concentration and oxygen delivery during CPB (r = 0.192, p < 0.0001; and r = 0.172, p = 0.0001, respectively), it correlated much more closely with baseline rSO2 (r = − 0.589, p < 0.0001). Thus, patients showing low baseline rSO2 primarily associated with preoperatively high BNP continued to show low rSO2 even during CPB independent of hemodynamics artificially controlled by CPB. Our findings suggest that low baseline rSO2 in patients with high BNP due to cardiac and/or renal diseases is more likely to result from tissue edema causing alterations in optical pathlength and thus in calculated rSO2 values, not readily modifiable with CPB, rather than actual cerebral hemodynamic alterations readily modifiable with CPB. These may partly explain why the INVOS oximeter is a trend monitor requiring baseline measures. [ABSTRACT FROM AUTHOR]

Poor trastuzumab (Tmab) response of patients with human epidermal growth factor receptor 2-overexpressing gastric or gastroesophageal junction adenocarcinoma (HER2-GEA) is associated with the inhibition of phosphatase and tensin homolog (PTEN) expression. In this multicenter, retrospective observational study, pathological samples of patients with HER2-GEA receiving Tmab-combined chemotherapy were immunohistochemically analyzed for PTEN expression. The primary endpoints were disease control rate (DCR), progression-free survival (PFS), and overall survival (OS). We assessed the effect of conventional chemotherapy and Tmab alone or combined with PI3K pathway inhibitors in vitro in HER2-GEA cells with or without PTEN expression. Twenty-nine and 116 patients were in the PTEN-loss and PTEN-positive groups, respectively. In patients with the target region, DCR was significantly lower in PTEN-loss patients than in PTEN-positive patients (67% and 87%, respectively, p = 0.049). The multivariate analysis demonstrated that PTEN loss was significantly associated with shorter PFS (HR = 1.63, p = 0.035) and OS (HR = 1.83, p = 0.022). PTEN knockdown did not affect the cytostatic effect of 5-FU and cisplatin, whereas Tmab combined with the PI3K/mTOR inhibitor NPV-BEZ235 suppressed PTEN-knockdown cell proliferation. In patients with HER2-GEA, PTEN loss is a predictive biomarker of Tmab resistance and prognostic factor. Molecular-targeted therapy with a PI3K/mTOR inhibitor would be effective for HER2-GEA with PTEN loss. [ABSTRACT FROM AUTHOR]

Risk-sensitive asset management on both finite and infinite time horizons are treated on a market with a bank account and a risky stock. The risk-free interest rate is formulated as a geometric Brownian motion, and affects the return of the risky stock. The problems become standard risk-sensitive control problems. We derive the Hamilton–Jacobi–Bellman equations and study these solutions. Using solutions, we construct optimal strategies and optimal values. [ABSTRACT FROM AUTHOR]

Background: Presently, there is no consensus as to what procedure of intracorporeal esophagojejunostomy (EJS) in totally laparoscopic total gastrectomy (TLTG) is best to reduce postoperative complications. The aim of this study was to demonstrate the superiority of linear stapled reconstruction in terms of anastomotic-related complications for EJS in TLTG.Methods: We collected data on 829 consecutive gastric cancer patients who underwent TLTG reconstructed by the Roux-en-Y method with radical lymphadenectomy between January 2010 and December 2016 in 13 hospitals. The patients were divided into two groups according to reconstruction method and matched by propensity score. Postoperative EJS-related complications were compared between the linear stapler (LS) and the circular stapler (CS) groups.Results: After matching, data from 196 patients in each group were analyzed. The overall incidence of EJS-related complications was significantly lower in the LS group than in the CS group (4.1% vs. 11.7%, p = 0.008). The incidence of EJS anastomotic stenosis during the first year after surgery was significantly lower in the LS group than in the CS group (1.5% vs. 7.1%, p = 0.011). The incidence of EJS bleeding did not differ significantly between the groups, although no bleeding was observed in the LS group (0% vs. 2.0%, p = 0.123). The incidence of EJS leakage did not differ significantly between the groups (2.6% vs. 3.6%, p = 0.771).Conclusion: The use of linear stapled reconstruction is safer than the use of circular stapled reconstruction for intracorporeal EJS in TLTG because of its lower risks of stenosis. [ABSTRACT FROM AUTHOR]

Background: Increased B-type natriuretic peptide (BNP) and decreased free triiodothyronine (fT3) are associated with increased mortality after cardiac surgery. However, previous studies have addressed mortality primarily in patients undergoing coronary artery bypass graft, and not in those undergoing valve surgery. We assessed abilities of BNP and fT3 to predict mortality after valve surgery. Methods: This retrospective study included 1050 consecutive patients who underwent valve surgery with normothermic cardiopulmonary bypass (CPB). Predictors of in-hospital mortality were identified with logistic regression analyses. Cutoff values were determined with receiver operating curve analyses. Results: There were 23 deaths (2.2%). By univariate analyses, fT3, log-transformed BNP (log BNP), cholinesterase, estimated glomerular filtration rate, and albumin were profoundly associated with in-hospital mortality (p < 0.0001 for each). By a multivariate analysis, however, only fT3 and log BNP remained significant (p = 0.0053 and p = 0.0449, respectively). fT3 and log BNP remained significant after adjustment for CPB time, and also after adjustment for the EuroSCORE II or JapanSCORE (p < 0.05 for each). Odds ratio and 95% confidence interval from univariate binary analysis for in-hospital mortality were 7.22 (3.12–17.58) for fT3 ≤ 2.21 pg/mL, 6.01 (2.54–15.77) for BNP ≥ 219 pg/mL, and 9.79 (4.21–22.74) for both combined (p < 0.0001 for each). Conclusions: fT3 and BNP predict in-hospital mortality after valve surgery, independent of each other, independent of CPB time, and independent of established mortality risk SCOREs. Additions of fT3 and BNP may enhance predictive utilities of established mortality risk SCOREs. [ABSTRACT FROM AUTHOR]

We consider an optimal investment, consumption, and life insurance purchase problem for a wage earner. We treat a stochastic factor model that the mean returns of risky assets depend linearly on underlying economic factors formulated as the solutions of linear stochastic differential equations. We discuss the partial information case that the wage earner can not observe the factor process and use only past information of risky assets. Then, our problem is formulated as a stochastic control problem with partial information. Applying the dynamic programming principle, we derive a coupled system of the Hamilton–Jacobi–Bellman (HJB) equation and two backward stochastic differential equations (BSDEs), and obtain the explicit solution. Finally, we strictly prove the verification theorem, and construct the optimal investment-consumption-insurance strategy. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer (GC) patients with positive peritoneal lavage cytology (CY1) and/or localized peritoneum metastasis (P1a) are defined as stage IV in the 15th edition of the Japanese Classification of Gastric Cancer. In Japan, the most common treatment for patients with CY1 and/or P1a is gastrectomy followed by postoperative chemotherapy. Patients and Methods: Subjects in this multi-institutional retrospective study were GC patients with CY1 and/or P1a who received surgical resection that leaves no macroscopically visible disease. Patients were selected from 34 institutions in Japan between 2007 and 2012. Selection criteria included adenocarcinoma, no distant metastasis except CY1 and P1a, and no prior treatment for GC before surgery. Results: Among 824 patients registered, 506 were identified as eligible, with a background of P0CY1, P1aCY0, or P1aCY1 (72.5%, 16.0%, and 11.5% of subjects, respectively). Sixty-two patients had not received postoperative chemotherapy (no-Cx), whereas 444 patients had received postoperative chemotherapy: S-1 monotherapy (S-1; n = 267, 52.7%), cisplatin plus S-1 (CS; n = 114, 22.5%), and others (n = 63, 12.6%). Overall survival (OS) was 29.5, 24.7, 25.4 and 9.9 months in the S-1, CS, 'others', and no-Cx groups, respectively [CS vs. S-1: hazard ratio (HR) 1.15, 95% confidence interval (CI) 0.89–1.50; p = 0.275]. In multivariate analysis, OS was similar between the S-1 and CS groups (CS vs. S-1: HR 1.19, 95% CI 0.92–1.55; p = 0.18). Conclusions: Postoperative chemotherapy after gastrectomy that leaves no macroscopically visible disease may have some survival benefits for GC patients with CY1 and/or P1a. In contrast, S-1 plus cisplatin seems to have no additional benefit over S-1 treatment alone. [ABSTRACT FROM AUTHOR]

Background: The authors previously showed the significant efficacy of S-1 plus cisplatin for gastric cancer with limited peritoneal metastasis. They conducted a phase 2 study to evaluate the safety and efficacy of induction chemotherapy using a docetaxel, cisplatin, and S-1 (DCS) triplet regimen to treat gastric cancer with peritoneal metastasis. Methods: The key eligibility criteria were gastric cancer with peritoneal metastasis or positive peritoneal cytology but no other distant metastases and capability of oral administration. The patients received three 28-day cycles of DCS (60 mg/m2 of cisplatin, 40 mg/m2 of docetaxel on day 1, and 80 mg/m2 of S-1 from day 1 to day 14), then underwent D2 gastrectomy if R0 was possible. The primary end point was the R0 resection rate. The sample size was determined to have 80% power for detecting a 20% improvement in the R0 resection rate over a 45% baseline for a one-tailed alpha of 0.1. Results: Among 30 enrolled patients, 24 completed three cycles of DCS. The most frequent grade 3 or 4 toxicity was neutropenia (60%). A complete response of peritoneal metastasis was observed in 16 patients, and 14 patients achieved R0 resection (47%; 95% confidence interval 28–66%). When the extent of peritoneal metastasis was classified as P0CY1, P1, P2, and P3 according to the Japanese classification, the R0 resection rates were respectively 63%, 60%, 46% and 0%. Conclusions: Induction chemotherapy with DCS is safe and can achieve R0 resection for some patients with limited peritoneal metastasis or positive peritoneal cytology. The efficacy, however, appears similar to that of S-1 plus cisplatin. [ABSTRACT FROM AUTHOR]

We consider a financial model that captures the characteristics of a large trader and an insider. This trader has some influence on the dynamics of prices. Moreover, the information of the insider is the final price plus a blurring noise that disappears as the final time approaches. In such a setting, we try to obtain the explicit solution of a risk-sensitive portfolio optimization problem with a finite time horizon. [ABSTRACT FROM AUTHOR]

The bacterial flagellum is a biological nanomachine for the locomotion of bacteria, and is seen in organisms like Salmonella and Escherichia coli. The flagellum consists of tens of thousands of protein molecules and more than 30 different kinds of proteins. The basal body of the flagellum contains a protein export apparatus and a rotary motor that is powered by ion motive force across the cytoplasmic membrane. The filament functions as a propeller whose helicity is controlled by the direction of the torque. The hook that connects the motor and filament acts as a universal joint, transmitting torque generated by the motor to different directions. This report describes the use of molecular dynamics to study the bacterial flagellum. Molecular dynamics simulation is a powerful method that permits the investigation, at atomic resolution, of the molecular mechanisms of biomolecular systems containing many proteins and solvent. When applied to the flagellum, these studies successfully unveiled the polymorphic supercoiling and transportation mechanism of the filament, the universal joint mechanism of the hook, the ion transfer mechanism of the motor stator, the flexible nature of the transport apparatus proteins, and activation of proteins involved in chemotaxis. [ABSTRACT FROM AUTHOR]

Risk-sensitive asset management problems, both those with a finite horizon and those with an infinite horizon, are studied in a financial market model that has a Wishart autoregressive-type jump-diffusion factor, which is a positive-definite symmetric matrix-valued process. The model describes the stochasticity of the market covariance structure, the interest rates, and the risk-premium of the risky assets. We obtain explicit representations of the solutions to the problems. [ABSTRACT FROM AUTHOR]

We consider risk-sensitive asset management on both finite and infinite time horizons. In particular, we treat the risk-seeking case. The returns and volatilities of the assets are random and affected by some economic factors, modeled as a diffusion process. The problems become standard risk-sensitive control problems. We derive the Hamilton-Jacobi-Bellman equations and study these solutions. Using solutions, we construct optimal strategies and optimal values. Moreover, we solve an upside large deviations probability maximization problem by conducting the duality relation with the infinite time horizon problem. [ABSTRACT FROM AUTHOR]

Background: The incidence of surgical site infection (SSI) is reportedly lower in laparoscopic colorectal surgery than in open surgery, but data on the difference in SSI incidence between colon and rectal laparoscopic surgeries are limited. Methods: The incidence and risk factors for SSI, and the effect of oral antibiotics in colon and rectal laparoscopic surgeries, were investigated as a sub-analysis of the JMTO-PREV-07-01 (a multicenter, randomized, controlled trial of oral/parenteral vs. parenteral antibiotic prophylaxis in elective laparoscopic colorectal surgery). Results: A total of 582 elective laparoscopic colorectal resections, comprising 376 colon surgeries and 206 rectal surgeries, were registered. The incidence of SSI in rectal surgery was significantly higher than in colon surgery (14 vs. 8.2 %, P = 0.041). Although the incidence of incisional SSI was almost identical (7 %) between the surgeries, the incidence of organ/space SSI in rectal surgery was significantly higher than in colon surgery (6.3 vs. 1.1 %, P = 0.0006). The lack of oral antibiotics was significantly associated with the development of SSI in colon surgery. Male sex, stage IV cancer, and abdominoperineal resection were significantly associated with SSI in rectal surgery. The combination of oral and parenteral antibiotics significantly reduced the overall incidence of SSI in colon surgery (relative risk 0.41, 95 % confidence interval 0.19-0.86). Conclusion: The incidence of SSI in laparoscopic rectal surgery was higher than in colon surgery because of the higher incidence of organ/space SSI in rectal surgery. The risk factors for SSIs and the effect of oral antibiotics differed between these two procedures. [ABSTRACT FROM AUTHOR]

For OS, non-platinum containing regimen, two or more sites of metastases, and PTEN loss were significantly related to shorter OS in patients with HER2-GEA based on the univariate analysis (p = 0.049, p = 0.002, and p = 0.023, respectively). For OS, platinum-containing regimen, two or more lesions of metastases, and PTEN loss were significantly related to shorter OS in patients with HER2-GEA based on the univariate analysis (p = 0.049, p = 0.002, and p = 0.023, respectively). [Extracted from the article]

Background: Distal gastrectomy with Billroth-I reconstruction (DGBI) is the most commonly used treatment approach for gastric cancer patients in Japan. The aim of this study was to assess and elucidate the effect of different surgical DGBI techniques on postgastrectomy syndrome (PGS) using the Postgastrectomy Syndrome Assessment Scale-45 (PGSAS-45). Methods: The newly created PGSAS-45 composed of 45 questions was used in this study. The scale was distributed to 2,922 patients who underwent gastrectomy >1 year prior. Completed forms were returned by 2,520 patients (86 %), of which 909 underwent DGBI. The effects of performing the Kocher maneuver, differences in the size of the gastric remnant and differences the anastomosis technique had on the main outcome measures of PGSAS-45 were analyzed. Results: Patients for whom the Kocher maneuver was performed experienced significantly worse meal-related distress and poorer quality of ingestion. Additionally, a less satisfactory physical and mental component summary from the SF-8 was reported. Patients with larger gastric remnants showed significantly better scores on the diarrhea subscale, a slightly better trend for the need for additional meals and dissatisfaction with eating. Regarding the anastomosis technique, there was no difference between the hand-sewn, circular stapler (CS) and linear stapler end-to-end anastomosis, and there was also no difference between the end-to-end and side-to-end anastomosis with the CS. Conclusions: The Kocher maneuver may increase meal-related distress, reduce the quality of ingestion and impart a negative effect on quality of life (QOL). The larger gastric remnants may cause reduction in diarrhea and an improvement in meal-related scores. [ABSTRACT FROM AUTHOR]

Purpose: We assessed the incidence of coronary artery disease (CAD) during hospitalization after emergency surgery for a type A acute aortic dissection. Methods: A total of 123 patients underwent multi-slice computed tomography (MSCT) scans during an early stage after surgery. The patients were divided into two groups: group I consisted of 14 patients (11.4 %) who had coronary artery stenosis of more than 75 % on MSCT, and group II consisted of 109 patients (88.6 %) who had no coronary lesions. Results: The prevalence of diabetes, dyslipidemia and a smoking history was significantly higher in group I. Although the serum low-density lipoprotein cholesterol levels were similar, the high-density lipoprotein cholesterol (HDL) level was significantly lower in group I (36.4 ± 7.9 mg/dl) than in group II (49.6 ± 13.5 mg/dl, P = 0.0005). The maximum carotid intima-media thickness (IMT) was significantly thicker in group I (1.17 ± 0.37 mm) compared to group II (0.96 ± 0.33 mm, P = 0.0297). The logistic regression analysis detected that a carotid IMT over 1.1 mm (odds ratio 4.35, P = 0.0371) and HDL less than 40 mg/dl (odds ratio 3.90, P = 0.0482) were predictors for CAD. Conclusions: CAD screening should be recommended for patients with aortic dissection who have several atherosclerosis risk factors, even after emergency surgery. [ABSTRACT FROM AUTHOR]

Purpose: Anatomical liver resection is usually based on Couinaud's anatomical concept. In contrast, Hjortsjo's concept, which divides the right anterior section of the liver into ventral and dorsal segments by the vertical plane named the ventral segment fissure (VSF), has been rarely utilized for liver resection. Identification of the VSF is the most difficult step in liver resection based on Hjortsjo's concept. This study aimed to detail liver resection based on Hjortsjo's concept and report surgical outcomes of this procedure. Methods: We reviewed the records of 166 consecutive patients who underwent liver resection between September 2009 and June 2012 at Kyoto Medical Center and identified seven liver resections in which Hjortsjo's concept was utilized. These patients consisted of four men and three women aged 55-79 years. Four patients had hepatocellular carcinoma and cirrhosis and three patients had metachronous colorectal liver metastasis. Results: Liver resection along the VSF consisted of two extended left medial sectionectomies, three extended right posterior sectionectomies, and one Sg 7+8-dorsal resection by a venous-drainage-guided approach and one Sg 8-dorsal resection by a Glissonian approach. In all patients, the VSF was successfully identified as a congested or ischemic border on the liver surface. Mortality and major morbidity were nil. No patients underwent blood transfusion. After a median follow-up of 15 months, there were no deaths or local recurrence. Conclusions: Anatomical liver resection based on Hjortsjo's concept is feasible and advantageous over conventional liver resection because it preserves more parenchyma. The venous-drainage-guided approach is an effective method for identifying the VSF. [ABSTRACT FROM AUTHOR]

Purpose: Postcardiotomy cardiogenic shock is still associated with a poor prognosis. We reviewed patients undergoing extracorporeal membrane oxygenation (ECMO) support for postcardiotomy cardiogenic shock and assessed their long-term outcomes. Methods: The subjects were 47 patients who received ECMO support for cardiogenic shock after open heart surgery. We analyzed the long-term survival and risk factors for early or late death. Results: Twenty-nine patients were weaned off ECMO support, but 15 of these patients died during their hospital stay. An independent predictor of mortality during ECMO support was incomplete sternum closure (OR 4.089, 95 % CL 1.003-16.67, p = 0.049) and a predictor of mortality after weaning off ECMO was more than 48 h of support (OR 8.975, 95 % CL 1.281-62.896, p = 0.027). Fourteen patients were discharged from hospital, but seven of these patients died during the follow-up period owing to cardiac events ( n = 2) or non-cardiac causes ( n = 5). The actuarial survival rates were 34.0 % at 30 days, 29.8 % at 1 year, and 17.6 % at 10 years. Conclusion: Although postcardiotomy cardiogenic shock requiring ECMO support is associated with high morbidity and mortality, the long-term survival rate is acceptable. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed (1) to evaluate the impact of clinical factors, particularly operation by trainees, on the short-term outcomes of laparoscopic resection for sigmoid and rectosigmoid cancer, and (2) to determine patients suitable for operation by trainees. Methods: From a prospectively maintained single-institution database, we identified 133 patients who underwent laparoscopic resection for sigmoid or rectosigmoid cancer between 2007 and 2010. Gender, age, body mass index (BMI), previous abdominal surgery, tumor location, tumor size, tumor stage, extent of lymph node dissection, and primary surgeon were evaluated using univariate and multivariate analyses to determine the predictive significance of these variables on surgical outcomes including operative time, blood loss, complication, postoperative stay, and retrieved lymph nodes. Results: Multivariate analysis showed that location of the tumor in the rectosigmoid ( p < 0.001), higher BMI ( p < 0.001), operation by trainees ( p < 0.001), male gender ( p = 0.002), and greater tumor depth ( p = 0.011) were independently predictive of longer operative time. Larger tumor size ( p = 0.025) and higher BMI ( p = 0.040) were independently predictive of greater blood loss. Larger tumor size was also related to longer postoperative stay ( p = 0.001) and a greater number of retrieved lymph nodes ( p = 0.001). Conclusions: This study identified operation by trainees as an independent risk factor for longer operative time but with no negative impact on any of the other outcomes. Female patients with a low BMI, sigmoid cancer, shallow tumor depth, and/or small tumor are suitable for operation by trainees. [ABSTRACT FROM AUTHOR]

Cardiogenic shock is associated with a high mortality rate in patients with acute myocardial infarction (AMI). We developed a new treatment approach named heart rest therapy (HRT) for complete revascularization in the early stage of AMI using an ultra-short-acting β-blocker (landiolol) and an Impella left ventricular assist device and verified the effect of this therapy in a swine model. In 18 male pigs, AMI was induced by left anterior descending coronary artery occlusion at the level of the second diagonal branch for 120 min, followed by 240 min of reperfusion. The animals were divided into three groups: group A had no support, group B was supported with the Impella, and group C was treated with HRT from 90 min after ischemia to 240 min after reperfusion. Infarct ratio (percentage of the infarct area relative to the area at infarct risk) was significantly reduced in group C (group A 65.38 ± 6.07, group B 39.66 ± 11.16, group C 21.78 ± 7.29), with a significant difference between groups A and B ( P < 0.001), A and C ( P < 0.001), and B and C ( P = 0.006). Heart rates were significantly lower in group C at 30 min ( P = 0.01), 60 min ( P = 0.022), and 240 min ( P = 0.032) after reperfusion compared with group B, without development of hypotension. HRT at the early stage in AMI stabilized the hemodynamic conditions and reduced infarct size and complications in a swine model. These results suggest that HRT can improve the prognosis of patients with AMI. [ABSTRACT FROM AUTHOR]

Background: This study aims to evaluate the clinical and anatomical factors, particularly pelvic dimensions that influence the difficulty of performing laparoscopic anterior resection for rectal cancer.Methods: We studied 50 consecutive patients who underwent laparoscopic anterior resection with double-stapling technique (DST) anastomosis for rectal cancer between January 2006 and February 2010. Staging was performed by computed tomography. Five pelvic dimensions (anteroposterior and transverse diameters of pelvic inlet and outlet, and pelvic depth) were measured using three-dimensional volume-rendering images. We also examined a number of other clinical characteristics, including gender, history of laparotomy, body mass index (BMI), operator, tumor location, tumor depth, nodal involvement, and tumor diameter. Univariate and multivariate analyses were performed to determine the predictive significance of these variables on surgical difficulty based on operative time and intraoperative blood loss.Results: Males had significantly shorter pelvic inlets and outlets and significantly greater pelvic depth than females. However, gender did not significantly affect surgical outcomes, although males did tend to experience greater blood loss. Maximum tumor diameter (p=0.014), BMI (p=0.001), operator (p<0.001), and tumor location (p=0.009) were independent predictors of operative time, which, in turn, was related to intraoperative blood loss (p<0.001).Conclusions: Maximum tumor diameter, BMI, operator experience, and tumor location can be used to predict the operative time required to complete laparoscopic anterior resection with DST anastomosis for rectal cancer, with no correlations between pelvic dimensions and operative time. The difficulty of the procedure was not related to patients' pelvic dimensions, which led us to conclude that "narrow pelvis" is not a contraindication for this surgery. Based on these results, we suggest that laparoscopic anterior resection should be performed by experienced surgeons in patients with large tumors, high BMI, and/or extraperitoneal rectal cancer. [ABSTRACT FROM AUTHOR]

With a bank account and a risky stock, both of which are affected by Cox-Ingersoll-Ross's interest rates, we treat two 'down-side risk' minimization problems of the large deviation probability for long-term investment. Explicit solutions of the problems are given by solving the associated risk-sensitive portfolio optimization problems. [ABSTRACT FROM AUTHOR]

risk-sensitive stochastic control problem with finite/infinite horizon is studied with a 1-dimensional controlled process defined by a linear SDE with a linear control-term in the drift. In the criterion function, a non-linear/quadratic term is introduced by using the solution to a Riccati differential equation, and hence, the problem is not ELQG (Exponential Linear Quadratic Gaussian) in general. For the problem, optimal value and control are calculated in explicit forms and the set of admissible risk-sensitive parameters is given in a concrete form. As applications, two types of large deviations control problems, i.e., maximizing an upside large deviations probability and minimizing a downside large deviations probability, are mentioned. [ABSTRACT FROM AUTHOR]

We consider an infinite time horizon optimal investment problem where an investor tries to maximize the probability of beating a given index. From a mathematical viewpoint, this is a large deviation probability control problem. As shown by Pham (in Syst. Control Lett. 49: 295–309, 2003; Financ. Stoch. 7: 169–195, 2003), its dual problem can be regarded as an ergodic risk-sensitive stochastic control problem. We discuss the partial information counterpart of Pham (in Syst. Control Lett. 49: 295–309, 2003; Financ. Stoch. 7: 169–195, 2003). The optimal strategy and the value function for the dual problem are constructed by using the solution of an algebraic Riccati equation. This equation is the limit equation of a time inhomogeneous Riccati equation derived from a finite time horizon problem with partial information. As a result, we obtain explicit representations of the value function and the optimal strategy for the problem. Furthermore we compare the optimal strategies and the value functions in both full and partial information cases. [ABSTRACT FROM AUTHOR]

We encountered a case with bilateral fistulas of coronary arteries into the right atrium, a rare cardiac anomaly. The case was a 17-year-old woman, who visited our hospital at the age of 11 because of fever. At that time, the patient was diagnosed as having a left coronary artery-right atrial fistula through cardiac catheterization (CAG). When the patient developed staphylococcus infected endocarditis at the age of 16, a thick fistula of the coronary artery, directly running from the deformed left coronary arterial sinus, a fistula of the left circumflex branch, and also a fistula of the right coronary artery into the right atrium were detected by CAG. The outlets of these fistulas were closed from the inside of the right atrium under artificial cardiopulmonary circulation and cardiac arrest, and each fistula was ligated at the outside of cardiac chambers. At that time, we took particular care that any branch of the sinuatrial node was not injured. Although all fistulas were confirmed to be closed by postoperative CAG, and no evidence of ischemia was detected by myocardial scintigraphy, deformity of the left coronary arterial sinus remained, requiring further follow up. [ABSTRACT FROM AUTHOR]

To estimate the effectiveness of concomitant usage of milrinone and catecholamine for weaning from cardiopulmonary bypass (CPB), a clinical study was made, in elective coronary artery by-pass grafting (CABG) cases. 24 consecutive patients underwent elective CABG in our institute. In all cases, moderate hypothermia and cardioplegic(St. Thomas solution) cardiac arrest were performed. In 12 cases, continuous intravenous 0.25 μg/kg/min of milrinone, 3 μg/kg/min of dobutamine (DOB) and dopamine (DOA) as the initial doses, were used concomitantly as inotropic agents (Group-I). The same initial doses of catecholamine (DOB and DOA) as the Group-I were administered in another 12 patients (Group-II). When the pump flow of CPB decreased to a half, these drugs were administered in both groups. Hemodynamic data were measured before CPB, just after operation, 3,6,12,24,48, and 72 hours after operation. There were no significant differences in aortic and pulmonary artery pressure between both groups. However, cardiac index (CI) of the Group-I demonstrated significantly (p<0.01) higher values than that of Group-II until 24 hours after surgery. Systemic vascular resistance index (SVRI) of the Group-I demonstrated significantly (p<0.01) lower value than that of Group-II from 3 to 12 hours after operation. There were no significant differences in oxygen delivery (D0) and oxygen consumption (VO) between both groups. These results suggested that concomitant usage of milrinone and low dose catecholamine increased CI and decreased SVRI, and made weaning from CPB very easy, demonstrating excellent hemodynamics. This high potential phosphodiesterase inhibitor may be suitable for not only weaning from CPB but also post-cardiotomy cardiogenic shock. [ABSTRACT FROM AUTHOR]

The aim of the present study was to assess the relationship between acute aortic dissection (AAD) and sleep disorders in a working population. Seventy (50.4%) of 139 younger subjects with AAD suffered from sleep disorders. Insomnia was reported by 35 patients (50%), sleep deprivation by 31 patients (44.3%), and sleep apnea syndrome was present in 43 patients (61.4%). The average apnea-hypopnea index was 22.0 ± 7.5 points, requiring appropriate treatment. Most of these patients had irregular daily schedules due to job pressure. Sixty-six (94.3%) complained of severe mental and physical stress in daily life. Sleep disorders are considered one of the risk factors for the occurrence of AAD at younger active ages. In primary care for patients with mental or physical stress due to their daily life, it is important to assess these individuals for the presence of sleep disorders. [ABSTRACT FROM AUTHOR]

Background: Pancreatoenteric anastomotic failure is the main cause of pancreatic fistula after pancreaticoduodenectomy (PD). Double purse-string telescoped pancreaticogastrostomy, reported by Addeo et al., is an easy and safe procedure. The aim of this article was to introduce our technique of pancreaticogastrostomy using an atraumatic self-retaining ring retractor (Alexis Wound Retractor) in a patient undergoing subtotal stomach-preserving PD (SSPPD). Patient and Methods: An 82-year-old woman presented with pancreatic cancer located in the uncinate process of pancreas. She underwent SSPPD with resection of the superior mesenteric vein (SMV) and double purse-string telescoped pancreaticogastrostomy using an Alexis wound retractor . Results: The pancreas was transected on the portal vein and the remnant pancreas was separated from the splenic vein and artery. After extirpation of specimens and reconstruction of the SMV, two seromuscular purse-string sutures were placed on the posterior wall of the upper stomach. The anterior wall of the upper stomach was incised and opened using an Alexis wound retractor . The remnant pancreas was inserted into the gastric cavity through the posterior wall of the stomach and sutured circumferentially with running stitches to fix on the gastric muco-muscular layer. After closure of the anterior wall of the stomach, purse-string sutures were tightened and pancreaticogastrostomy was completed. The patient's postoperative course was uneventful and a computed tomography imaging study revealed no fluid collection around the pancreaticogastrostomy. This patient was discharged on the 14th postoperative day. Conclusions: Use of an Alexis wound retractor makes it easier to perform a double purse-string telescoped pancreaticogastrostomy by a self-expanding property to allow a wide operative view. [ABSTRACT FROM AUTHOR]

Background: Clinical findings and postoperative follow-up data on remnant gastric cancer (RGC) are limited due to its rarity. Additionally, the preoperative staging, radical surgery, and managing recurrence in RGC present significant clinical challenges.We analyzed the clinicopathological findings, adjuvant chemotherapy, and patterns of postoperative recurrence of 313 consecutive patients who underwent curative surgery for RGC at 17 Japanese institutions. This study investigated the optimal management of RGC and the impact of adjuvant chemotherapy (AC) on recurrence-free survival (RFS).Pathological stages I, II, and III were observed in 55.9% (N = 175), 24.9% (N = 78), and 19.2% (N = 60) of the patients, respectively. The overall concordance rate between clinical and pathological T staging was 58.3%, with a clinical T4 sensitivity of 41.4% for diagnosing pathological T4. During the median follow-up period of 4.6 years, disease recurrence occurred in 24.3% of patients. Most recurrences (over 80%) occurred within 2.5 years, and 96.1% within 5 years after RGC surgery. Peritoneal recurrence was the most common in patients with advanced RGC, accounting for 14.1% in stage II and 28.3% in stage III. Multivariable regression analysis showed that AC was significantly associated with a longer RFS, with a hazard ratio of 0.45 (95% confidence interval: 0.26–0.76).Our study underscores the importance of early detection, accurate preoperative staging, and postoperative surveillance in managing advanced RGC cases. Despite some limitations, our findings indicate that AC may provide survival benefits comparable to those seen in primary gastric cancer.Methods: Clinical findings and postoperative follow-up data on remnant gastric cancer (RGC) are limited due to its rarity. Additionally, the preoperative staging, radical surgery, and managing recurrence in RGC present significant clinical challenges.We analyzed the clinicopathological findings, adjuvant chemotherapy, and patterns of postoperative recurrence of 313 consecutive patients who underwent curative surgery for RGC at 17 Japanese institutions. This study investigated the optimal management of RGC and the impact of adjuvant chemotherapy (AC) on recurrence-free survival (RFS).Pathological stages I, II, and III were observed in 55.9% (N = 175), 24.9% (N = 78), and 19.2% (N = 60) of the patients, respectively. The overall concordance rate between clinical and pathological T staging was 58.3%, with a clinical T4 sensitivity of 41.4% for diagnosing pathological T4. During the median follow-up period of 4.6 years, disease recurrence occurred in 24.3% of patients. Most recurrences (over 80%) occurred within 2.5 years, and 96.1% within 5 years after RGC surgery. Peritoneal recurrence was the most common in patients with advanced RGC, accounting for 14.1% in stage II and 28.3% in stage III. Multivariable regression analysis showed that AC was significantly associated with a longer RFS, with a hazard ratio of 0.45 (95% confidence interval: 0.26–0.76).Our study underscores the importance of early detection, accurate preoperative staging, and postoperative surveillance in managing advanced RGC cases. Despite some limitations, our findings indicate that AC may provide survival benefits comparable to those seen in primary gastric cancer.Results: Clinical findings and postoperative follow-up data on remnant gastric cancer (RGC) are limited due to its rarity. Additionally, the preoperative staging, radical surgery, and managing recurrence in RGC present significant clinical challenges.We analyzed the clinicopathological findings, adjuvant chemotherapy, and patterns of postoperative recurrence of 313 consecutive patients who underwent curative surgery for RGC at 17 Japanese institutions. This study investigated the optimal management of RGC and the impact of adjuvant chemotherapy (AC) on recurrence-free survival (RFS).Pathological stages I, II, and III were observed in 55.9% (N = 175), 24.9% (N = 78), and 19.2% (N = 60) of the patients, respectively. The overall concordance rate between clinical and pathological T staging was 58.3%, with a clinical T4 sensitivity of 41.4% for diagnosing pathological T4. During the median follow-up period of 4.6 years, disease recurrence occurred in 24.3% of patients. Most recurrences (over 80%) occurred within 2.5 years, and 96.1% within 5 years after RGC surgery. Peritoneal recurrence was the most common in patients with advanced RGC, accounting for 14.1% in stage II and 28.3% in stage III. Multivariable regression analysis showed that AC was significantly associated with a longer RFS, with a hazard ratio of 0.45 (95% confidence interval: 0.26–0.76).Our study underscores the importance of early detection, accurate preoperative staging, and postoperative surveillance in managing advanced RGC cases. Despite some limitations, our findings indicate that AC may provide survival benefits comparable to those seen in primary gastric cancer.Conclusions: Clinical findings and postoperative follow-up data on remnant gastric cancer (RGC) are limited due to its rarity. Additionally, the preoperative staging, radical surgery, and managing recurrence in RGC present significant clinical challenges.We analyzed the clinicopathological findings, adjuvant chemotherapy, and patterns of postoperative recurrence of 313 consecutive patients who underwent curative surgery for RGC at 17 Japanese institutions. This study investigated the optimal management of RGC and the impact of adjuvant chemotherapy (AC) on recurrence-free survival (RFS).Pathological stages I, II, and III were observed in 55.9% (N = 175), 24.9% (N = 78), and 19.2% (N = 60) of the patients, respectively. The overall concordance rate between clinical and pathological T staging was 58.3%, with a clinical T4 sensitivity of 41.4% for diagnosing pathological T4. During the median follow-up period of 4.6 years, disease recurrence occurred in 24.3% of patients. Most recurrences (over 80%) occurred within 2.5 years, and 96.1% within 5 years after RGC surgery. Peritoneal recurrence was the most common in patients with advanced RGC, accounting for 14.1% in stage II and 28.3% in stage III. Multivariable regression analysis showed that AC was significantly associated with a longer RFS, with a hazard ratio of 0.45 (95% confidence interval: 0.26–0.76).Our study underscores the importance of early detection, accurate preoperative staging, and postoperative surveillance in managing advanced RGC cases. Despite some limitations, our findings indicate that AC may provide survival benefits comparable to those seen in primary gastric cancer. [ABSTRACT FROM AUTHOR]