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Banks make profits from the difference between short-term and long-term loan interest rates. To issue loans, banks raise funds from capital markets. Since the long-term loan rate is relatively stable, but short-term interest is usually variable, there is an interest rate risk. Therefore, banks need information about the optimal leverage strategies based on the current economic situation. Recent studies on the economic crisis by many economists showed that the crisis was due to too much leveraging by “big banks”. This leveraging turns out to be close to Kelly’s optimal point. It is known that Kelly’s strategy does not address risk adequately. We used the return−drawdown ratio and inflection point of Kelly’s cumulative return curve in a finite investment horizon to derive more conservative leverage levels. Moreover, we carried out a sensitivity analysis to determine strategies during a period of interest rates increase, which is the most important and risky period to leverage. Thus, we brought theoretical results closer to practical applications. Furthermore, by using the sensitivity analysis method, banks can change the allocation sizes to loans with different maturities to mediate the risks corresponding to different monetary policy environments. This provides bank managers flexible tools in mitigating risk.

Few data regarding popliteal artery entrapment syndrome (PAES) is available in Japan. In this study, we investigated incidence, diagnosis and treatment of PAES in current vascular practice. A retrospective analysis of all patients with PAES visiting 31 participating institutes between 2003 and 2015 was conducted. Thirty-five limbs (28 patients) were identified during the 13-year study period, and the incidence of PAES was 0.12% of all peripheral artery disease cases revascularized. Mean age was 32.0 ± 16.9 years old, and 60 and more years old was 10.7%. Also, 92.9% were male and 39.3% were athletes. Most frequent initial symptoms were intermittent claudication in 23 limbs (65.7%); 4 limbs (11.4%) had chronic limb-threatening ischemia. CT scan was most frequently (94.3%) used for the diagnostic imaging followed by MRI (45.7%) and duplex ultrasound (45.7%). Stress test such as dorsal flexion during duplex ultrasound was used only in 28.6%. Thirty-two limbs (91.4%) received surgical treatment, including 23 arterial reconstructions (71.9%); there were no major perioperative complications. All patients achieved improvement of their symptoms, and the average ankle brachial index increased from 0.69 ± 0.22 to 1.00 ± 0.14 post-surgery. The average postoperative follow-up period was 26.0 months with only one reintervention during the follow-up. In conclusion, PAES was a rare condition and traditional surgical treatment was solid. However, given a broad spectrum of clinical feature of PAES and less usage of diagnostic duplex ultrasound with stress test, there might be a miss- or delayed diagnosis of PAES even in the current vascular practice., (© 2020. Japanese Association of Cardiovascular Intervention and Therapeutics.)

Objectives: Lymph transportation through the body is partly controlled by the intrinsic pumping of lymphatic vessels. Although an understanding of this process is important for medical application, little is currently known because it is difficult to measure. Here, we introduce an easy, safe, and cost-effective technique for measuring lymphatic pumping in leg superficial lymphatic vessels. Readings obtained with this technique were compared with values obtained with dynamic lymphoscintigraphy. Differences in lymphatic pumping between healthy volunteers and patients with lymphedema were also investigated., Methods: Indocyanine green (ICG) fluorescence lymphography was performed by subcutaneously injecting 0.3 mL of ICG (0.5%) into the dorsum of the foot. Real-time fluorescence images of lymph propulsion were obtained with an infrared-light camera system with the individual supine or sitting. A custom-made transparent sphygmomanometer cuff was wrapped around the lower leg and connected to a standard mercury sphygmomanometer. The cuff was inflated to 60 mm Hg and then gradually deflated at 5-minute intervals to lower the pressure by 10-mm Hg steps until the fluorescence contrast agent exceeded the upper border of the cuff, indicating that the lymphatic contraction had overcome the cuff pressure. Lymph pumping pressure (P(pump)) was defined as the value of the cuff pressure when the contrast agent exceeded the upper border of the cuff. We measured P(pump) among healthy volunteers who maintained a supine position and compared these values with measurements obtained from lymphoscintigraphy. P(pump) values while sitting were also compared between 30 legs from healthy volunteers and 30 legs from lymphedematous patients., Results: Among healthy, supine participants, P(pump) was 25.2 ± 16.7 mm Hg (mean ± standard deviation [SD]) when measured by ICG fluorescence lymphography. These values were significantly correlated with values taken using dynamic lymphoscintigraphy (r(2) = 0.54, p < .01), while 2 SDs of the mean were approximately 20 mm Hg, suggesting a substantial disagreement between the two methods (Bland-Altman plots). In the comparison of seated measurements, readings for healthy participants (P(pump) = 29.3 ± 16.0) were higher than those for lymphedematous participants (13.2 ± 14.9)., Conclusion: ICG fluorescence is an accurate-as well as a safe, easy, and economical-method of measuring lymphatic pumping. Therefore, it may develop as a vital tool for diagnosing lymphatic malfunctions even when they are only in their formative stages. Studies that use this technique may increase our knowledge of the lymphatic system as a whole, allowing us to develop better treatments for lymphatic disorders., (Copyright © 2010 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Purpose: To assess the pelvic circulation during abdominal aortic aneurysm (AAA) repair by measuring the inferior mesenteric artery stump pressure (IMA-SP), penile blood flow, and gluteal blood flow., Methods: Twenty males were selected for this study. An aorto-bi-common iliac arteries (CIA) graft replacement was performed in ten patients (Group Bi-CIA). An aorto-right-CIA/left-external iliac artery (EIA) graft replacement was performed in five (Group Lt-EIA). The other five underwent an aorto-right-EIA/left-CIA anastomosis (Group Rt-EIA). The right graft limb was anastomosed first, followed by the left limb in all of the patients. Pelvic circulation was monitored during aortic reconstruction, including the IMA-SP index (IMA-SPI), penile brachial pressure index (PBI) by pulse-volume plethysmography, and gluteal tissue oxygenation metabolism with near-infrared spectroscopy by monitoring the gluteal tissue oxygenation index (TOI) bilaterally., Results: The PBI and bilateral gluteal TOI became depressed in all patients during proximal aortic clamping. However, there was no significant change in IMA-SPI in each group. The PBI and bilateral gluteal TOI in all groups recovered to the baseline values after completion of bilateral graft limb anastomosis., Conclusions: IMA-SPI is likely to reflect collateral circulation mainly from the superior mesenteric artery. The penile blood flow and bilateral gluteal blood flow therefore seem to be supplied via the bilateral hypogastric arteries or the profunda femoris arteries.

Bile leak remains a serious complication after hepatectomy. The conventional leak test by intrabiliary injection of normal saline solution is not sensitive. The authors present a new bile leak test using indocyanine green (ICG) fluorescence. After hepatic transection, ICG solution (.05 mg/mL) was intrabiliarily injected through a transcystic tube under distal common bile duct clamping, and fluorescent images were visualized using an infrared camera system. The ICG leak test was performed in 27 patients undergoing hepatectomy without biliary reconstruction. Bile leaks were intraoperatively found in 8 patients and fixed, resulting in no postoperative leaks. There was no adverse reaction to ICG. In contrast, postoperative bile leaks occurred in 2 of 32 patients who received the conventional leak test with normal saline solution between April 2007 and March 2008. The new bile leak test by ICG fluorography is useful to prevent postoperative bile leak., (Copyright (c) 2010 Elsevier Inc. All rights reserved.)

Gut barrier failure and the resultant translocation of luminal bacteria and bacterial products into the systemic circulation have been proposed as pathogenic mechanisms of multiorgan dysfunction syndrome (MODS) in open repair of abdominal aortic aneurysm (AAA). Our study aimed to demonstrate the direct release of gut-derived inflammatory mediators via the trans-serosal route in humans. Fifteen patients who underwent elective infrarenal open repair of AAA were randomized into two groups. In Group I patients (n = 10), the small intestine was exteriorized into a bowel bag. In Group II patients (n = 5), the small intestine was packed within the peritoneal cavity using large gauzes. We collected the bowel bag fluid in Group I and the ascites fluid, squeezed out from the gauzes at the end of surgery, in Group II. Leukocytes were collected from patients' blood samples. Incubation with the bowel bag fluid and ascites fluid caused a significant increase in both granulocyte pseudopod formation and CD11b expression compared to that with control fluid (p < 0.01). The addition of phospholipase A2 (PLA2) inhibitor quinacrine abolished leukocyte activation by the bowel bag fluid. Based on these results, we consider that trasns-serosal leakage of gut-derived mediators occurred during the open repair of AAA; further, sPLA2 may be the most potent mediator in the activation of leukocytes among such gut-derived mediators in AAA surgery.

Objectives: Venodynamics and lymphodynamics may interact as an inseparable and mutually dependent dual outflow system. This study investigated the effect of surgical treatment on lower limb lymph flow in patients with varicose veins., Methods: Thirty-nine patients with varicose veins in the lower limb (28 patients with unilateral limb, 11 patients with bilateral limb), who demonstrated great saphenous vein reflux, were investigated with air-plethysmography and indocyanine green (ICG) fluorescence lymphography before surgical treatment and 6 months later. Fifteen healthy volunteers participated in this study as a control. With air-plethysmography, venous volume (VV) and venous filling time were measured. Venous filling index (VFI) was calculated. For ICG lymphography, 0.3 mL of ICG (0.5%) was subcutaneously injected at the dorsum of the foot. After the injection, fluorescent image of ICG dye was traced on real-time video images using a near-infrared camera system. The interval until the dye reached the knee was measured (transit time [TT]) in a standing position, which was previously demonstrated to correlate with the interval measured using dynamic isotope lymphoscintigraphy., Results: In CEAP clinical stage venous disease, TT in patients with C4 approximately 6 and C2 approximately 3 was significantly longer than that in the control group (587 +/- 97 seconds, 484 +/- 82 seconds, 252 +/- 29 seconds, respectively, mean +/- SD, P < .01). Among all limbs with varicose veins, there were correlations between TT and VV (Pearson r = 0.31, P < .01), between TT and VFI (Pearson r = 0.48, P < .01). All patients underwent great saphenous vein stripping. Six months later, the venous clinical severity score significantly improved with significant reductions in both VV and VFI values. TT 6 months postoperatively was also significantly shorter than that before surgical treatment (501 +/- 67 seconds, 340 +/- 38 seconds, respectively, mean +/- SD, P < .01)., Conclusions: Varicose veins could affect lymphatic function and delay lymphatic flow in the lower limbs. Derangement of lymph flow may correlate with the severity of clinical venous disease and/or the magnitude of venous reflux, which could be reversible with surgical treatment of venous incompetence.

Background: Perfluorochemicals (PFC) are chemical substances that have a higher oxygen solubility under hyperbaric oxygen (HBO) pressure. This study investigated the effect of cold HBO-PFC/University of Wisconsin (UW) solution on preservation of rat small intestinal graft., Methods: We manufactured an air-tight, pressure-resistant tank made of stainless steel with high thermal conductivity. Rat ileal grafts were placed in a custom-made silicon-gum bag with UW solution, which was immersed in 5 atm HBO-PFC solution in the tank (Group P-5). The tank was kept at 4 degrees C. We compared the ATP concentration and mucosal permeability in Group P-5 with grafts preserved in 1 atm oxygenated-PFC/UW solution (Group P-1) and simple cold storage in UW solution (Group C). Histologic study was also performed., Results: PO(2) in UW solution after 48 h preservation were 1852 +/- 37, 499 +/- 13, and 173 +/- 3 mmHg (Group P-5, P-1 and C, respectively, mean +/- SD). At 48 h of preservation, graft ATP concentration was significantly greater in Group P-5 compared to that in Group P-1 and Group C. Mucosal hyperpermeability as well as mucosal morphologic changes were also ameliorated in Group P-5., Conclusion: HBO-PFC can supply a greater amount of oxygen to UW solution. Indirect measures of oxygen metabolism such as ATP content and lactate production suggested improvement in maintaining graft oxygen metabolism.

Background: Lymphoscintigraphy has largely been performed to diagnose lymphedema. It is, however a time-consuming and expensive technique, which has not been covered by Japanese medical insurance since the year 2002. In this report we introduce a new imaging technique of fluorescent lymphography to diagnose lymphedema., Methods: Fluorescence images of subcutaneous lymphatic drainage after subcutaneous injection of indocyanine green (ICG) at the foot were obtained using a newly developed near-infrared camera system. ICG fluorescent lymphography was performed in 12 patients with secondary lymphedema and 10 healthy volunteers. The 12 patients were diagnosed with secondary lymphedema according to the medical history and lymphoscintigram, of which 11 had a history of hysterectomy with extended lymph node dissection and local radiation therapy for uterine cancer. Lymphedema developed in one patient after femorotibial artery bypass for peripheral artery occlusive disease., Results: Four abnormal fluorescent patterns of the lymph drainage were observed in lymphedema: dermal backflow (an abnormal filling of the lymph capillaries), extended fluorescent signal at the dorsum and plantar region of the foot, dilated lymph channels with proximal obliteration, and diffuse glittering of fluorescent signals with scattered twinkling of the dye. Continuous lymph channels from the injection site of the foot to the groin were observed along the medial aspect of thigh in healthy subjects., Conclusion: ICG fluorescence lymphography is safe, simple, and minimally invasive. The device is portable and easy to use. The technique may be useful in clinical practice to identify presence of lymphatic disorder.

A 57-year-old woman was hospitalized with a left renal artery aneurysm (RAA). The aneurysm measured 35 mm in diameter and was located at the renal artery bifurcation. We performed a laparoscopic nephrectomy using a retroperitoneal approach and performed an ex vivo repair of the renal artery. The reconstructed kidney was then autotransplanted at the left iliac fossa. The patient's postoperative course was uneventful. A laparoscopic nephrectomy and ex vivo repair are both considered to be effective for treating complex RAA.

Although inferior vena cava (IVC) filter placement has demonstrated an excellent therapeutic efficacy in preventing pulmonary embolism, several filter-related complications have been reported. Among them, retroperitoneal hemorrhage due to IVC perforation is one of the most serious complications. We report herein a female patient who underwent TrapEase IVC filter placement with anticoagulation and thrombolytic therapy for treatment of pulmonary embolism, and later demonstrated hemorrhagic shock 5 days after filter placement. The patient's blood pressure stabilized after the anticoagulant therapy was stopped and she received a blood transfusion. We should therefore carefully observe patients after IVC filter placement, particularly those receiving simultaneous anticoagulation therapy.

Purpose: The endovascular repair (EVAR) of an abdominal aortic aneurysm (AAA) with a bilateral common iliac artery aneurysm (CIAA) often requires exclusion of the bilateral hypogastric artery (HA), which can be associated with pelvic ischemic complications such as erectile dysfunction and buttock claudication. This study assessed the effect of HA bypass on improving pelvic circulation., Methods: Five patients who underwent endovascular repair with HA bypass for an AAA with bilateral CIAA were evaluated. In all patients, the patency of the inferior mesenteric artery and bilateral HAs arteries was confirmed with preoperative computed tomography (CT) scans and angiography. During EVAR, penile blood flow was monitored with pulse-volume plethysmography measuring the penile brachial pressure index (PBI), and bilateral buttock blood flow was monitored with near-infrared spectroscopy measuring the gluteal tissue oxygenation index (TOI). An aortouni-external iliac artery stent graft with a crossover bypass was performed after embolization of the contralateral HA. HA bypass was performed between the crossover bypass graft and the ipsilateral HA via a retroperitoneal incision., Results: Unilateral coil embolization of the contralateral side HA trunk slightly decreased blood flow to the contralateral side buttock but did not cause significant changes in penile blood flow. At the completion of EVAR, the levels of both PBI and the contralateral side TOI were significantly lower than the baseline levels. After ipsilateral side HA revascularization with HA bypass, both PBI and bilateral gluteal flow returned almost to the baseline levels. Postoperative angiography and CT scans demonstrated the patency of all HA bypasses and no endoleaks. None of the patients experienced new onset of erectile dysfunction or buttock claudication 1 month after surgery., Conclusion: Bilateral HA interruption during EVAR for AAA with bilateral CIAA was associated with significant depletion of both penile and gluteal blood flow. Intraoperative monitoring of PBI and TOI at the bilateral buttocks showed significant improvement of both parameters after HA bypass. HA bypass is an excellent procedure to improve pelvic circulation despite its increased surgical complexity.

Perfluorochemicals (PFCs) have a high solubility for oxygen. We have previously demonstrated the effect of peritoneal lavage with oxygenated PFC (O2-PFC) on ameliorating ischemia/reperfusion (I/R)-induced intestinal ischemic damage in an animal model. In this study, we applied hyperbarically O2-PFC (HBO-PFC) to investigate whether a larger amount of oxygen carried by PFC could enhance the protective effect of O2-PFC during intestinal malperfusion. Rats were subjected to ischemia by clamping the superior mesenteric artery (SMA) for 90 min. The SMA was then declamped. Rats were divided into four groups. In group A, only anesthesia and abdominal incision were performed. In group B, SMA was clamped without O2-PFC. In group C, during the SMA clamp, 1 atm O2-PFC was injected into the abdominal cavity. In group D, 5 atm O2-PFC (HBO-PFC) was prepared using a custom-made hyperbaric oxygen tank and administered to the abdominal cavity during the SMA clamp. Ileal tissue adenosine triphosphate (ATP) levels 90 min after SMA declamping were determined using luciferase assay. To assess intestinal mucosal barrier function at 90 min after release of the SMA clip, everted gut sacs were prepared to measure the mucosal-to-serosal passage of fluorescein-conjugated dextran (FD4, molecular weight = 4 kDa). Thirty minutes after i.p. administration, partial pressure of oxygen in HBO-PFC remained around 1000 mmHg, whereas partial pressure of oxygen in 1 atm O2-PFC decreased to around 400 mmHg. The intestinal tissue ATP was significantly preserved in group D. Moreover, the mucosal hyperpermeability of the gut sac after I/R was significantly ameliorated in group D. Hyperbarically oxygenated perfluorochemical might supply a larger amount of oxygen to ischemic tissue during SMA clamp, which protected the small intestine from I/R injury, possibly caused by the maintenance of tissue ATP levels during ischemia.

Background: Portal triad occlusion (PTO) causes portal congestion and damages the intestinal mucosa, which is associated with portal endotoxemia. However, administration of a sublethal dose of endotoxin results in resistance to its toxic activities. We tested the hypothesis that portal congestion due to PTO induces endotoxin tolerance., Materials and Methods: Rats were subjected to PTO for 15 min. In Group 1, male rats underwent laparotomy and, 48 h after the surgery, a lethal dose of Escherichia coli lipopolysaccharide was administered. In Group 2, rats were subjected to PTO for 15 min. Then a lethal dose of LPS was administered 48 h after surgery. Group 3 was treated the same as Group 2, except that PTO was performed with portosystemic shunt. Group 4 was also treated same as Group 2, except that rats received polymixin B and neomycin by gavage to eliminate intestinal luminal bacteria before PTO. Survival was examined after the administration of a lethal dose of LPS. Changes in plasma levels of cytokine are also measured after the administration of LPS. The portal endotoxin level in each group after PTO was measured., Results: On survival test, only rats in Group 2 and Group 4 showed significantly higher survival rates. The portal endotoxin level was significantly elevated only in Group 2. The elevation of plasma cytokine levels (IL-6, TNF-alpha) and NO production (NO(2)(-)/NO(3)(-)) in Groups 2 and 4 were inhibited compare to those in Groups 1 and 3., Conclusions: PTO induced LPS tolerance possibly due to portal congestion and subsequent visceral congestion.

Purpose: To evaluate the efficiency of the form PWV/ABI (pulse wave velocity/ankle brachial pressure index) for measuring penile blood pressure (PBP) and the penile brachial pressure index (PBI)., Methods: We measured PBP and the PBI using both form PWV/ABI and Doppler ultrasonography in 40 men with surgical disorders., Results: By using pulse-volume recording, the form PWV/ABI can simultaneously measure PBP and bilateral brachial artery pressure, and calculate the PBI automatically. The data obtained showed strong correlations with those obtained by the conventional Doppler ultrasound technique. Moreover, measurements were completed within 5 min at the bedside and the data were stored in the device's memory., Conclusion: The form PWV/ABI is a useful tool for assessing pelvic hemodynamics and diagnosing vasculogenic impotence.