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To assess the radiological dose to the public resulting from the Fukushima Daiichi Nuclear Power Station (FDNPS) accident in Japan, especially for the early phase of the accident when no measured data are available for that purpose, the spatial and temporal distributions of radioactive materials in the environment need to be reconstructed through computer simulations using the atmospheric transport, dispersion, and deposition model (ATDM). For the ATDM simulation, the source term of radioactive materials discharged into the atmosphere is essential and has been estimated in many studies. In the present study, we further refined the source term estimated in our previous study and improved the ATDM simulation with an optimization method based on Bayesian inference, which used various measurements such as air concentration, surface deposition, fallout, and newly released hourly air concentrations of 137 Cs derived by analyzing suspended particulate matter (SPM) collected at air pollution monitoring stations. This optimization improved not only the source term but also the wind field in meteorological calculation, which led to the reduction of discrepancies in plume passage time at monitoring points to less than 3 h between calculations and measurements, by feeding back comparison results between the dispersion calculations and measurements of radionuclides. As a result, the total amounts of 137 Cs and 131 I by the present study became 1.0 × 10 16 and 1.2 × 10 17 Bq, respectively, and decreased by 29% and 20%, respectively, in comparison with those by previous study. The ATDM simulation successfully reproduced both the air concentrations at SPM monitoring points and surface depositions by airborne monitoring. FA10 for total samples of air concentrations of 137 Cs at SPM monitoring points increased from 35.9% by the previous study to 47.3%. The deposition amount on the land decreased from 3.7 × 10 15 Bq by the previous study to 2.1 × 10 15 Bq, which was close to the measured amount of 2.4 × 10 15 Bq. We also constructed the spatiotemporal distribution of some major radionuclides in the air and on the surface (optimized dispersion database) by using the optimized release rates and ATDM simulations. The optimized dispersion database can be used for comprehensive dose assessment in tandem with behavioral patterns of evacuees from the FDNPS accident by collaborating research group in the Japanese dose assessment project. The improvements in the present study lead to the refinement of the dose estimation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

A secondary aortoenteric fistula (SAEF) is a relatively rare complication of aortoiliac reconstructive surgery, often involving relatively fixed duodenal third portion and a vascular anastomosis. We observed a 52-year-old man with a recurrent right lower leg abscess following the erosion between ipsilateral bifurcated prosthetic graft limb and nonfixed jejunum. In situ graft-sparing surgical treatment with aggressive debridement was successfully performed. A SAEF may occur even at a nonvascular anastomosis site, or in nonfixed small bowel, and may become a source of a septic embolus. A high index of suspicion for SAEF is required for early diagnosis and treatment of this life-threatening complication., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Spontaneous isolated superior mesenteric artery (SMA) dissection is a rare condition, and its clinical and angiographic courses are poorly defined. We aimed to monitor the morphological characteristics of spontaneous isolated SMA dissection using computed tomography (CT) over 2 years of follow-up, including the recovery process via vascular remodeling, and identify the factors that affect vascular remodeling using univariate analysis., Methods and results: We retrospectively reviewed the medical records and morphological findings of 59 consecutive patients with spontaneous isolated SMA dissection between October 2007 and July 2014, which included 36 symptomatic and 23 asymptomatic patients. Surgical intervention with open laparotomy was required in 3 patients during the follow-up period; 41 patients who received conservative treatment were followed up over 2 years with regular CT. Complete remodeling was achieved in 16 of 25 symptomatic patients who were treated conservatively (64.0%). A patent false lumen and aneurysmal formation on an initial CT scan were identified as negative factors that affected remodeling in patients with spontaneous isolated SMA dissection., Conclusions: Conservative management of spontaneous isolated SMA dissection is associated with a good prognosis, both clinically and morphologically. Surgical intervention is only required in patients with severe intestinal ischemia or rapid aneurysmal enlargement. (Circ J 2016; 80: 1452-1459).

We reported three cases of mass-forming type 1 autoimmune pancreatitis (AIP) that were preoperatively suspected to be pancreatic cancer, and reviewed their clinicopathological features. Radiological findings in the patients revealed hypoattenuating masses in the early phase or a stricture of the main pancreatic duct with upstream dilatation, which was consistent with the diagnosis of pancreatic cancer. Histopathologically, the lesions were well demarcated and met all diagnostic criteria for immunoglobulin G4 (IgG4)-related AIP, including the presence of periductal lymphoplasmacytic infiltration, obliterative phlebitis, storiform fibrosis and abundant IgG4-positive plasma cells. However, the adjacent uninvolved pancreatic duct and lobular structures were well preserved. And in all patients, none or some of the aforementioned characteristics were observed. We suggest that some cases of focal AIP may progress to more severe grades and exhibit mass formation, although remaining localized. These focal cases of AIP are difficult to distinguish from pancreatic cancer. To our knowledge, this report is the first to present a histopathological comparison of mass-forming AIP with the adjacent uninvolved pancreatic tissues., (© 2016 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.)

Background: Hematemesis is uncommon as an initial presenting symptom in pancreatic cancer. We present herein a case of a pseudoaneurysm that ruptured and fistulized into the stomach. The pseudoaneurysm was secondary to a pancreatic pseudocyst complicating obstructive pancreatitis due to pancreatic cancer. The patient was successfully treated using trans-arterial embolization followed by curative surgery., Case Presentation: A 61-year-old man presented to the emergency room with hematemesis. Laboratory examinations revealed a low level of hemoglobin (5.0 g/dl). The patient had presented to another hospital due to hematemesis 1 month before presenting to our hospital. A low-density mass in the pancreatic body with dilatation of the distal main pancreatic duct and a pseudocyst in the pancreatic tail had been observed by radiology at the previous hospital. Further investigation had been planned. Abdominal computed tomography on admission to our hospital demonstrated a pseudoaneurysm in close contact with the wall of the pseudocyst of the pancreatic tail, compressing the stomach. The pseudoaneurysm had not been detected by abdominal computed tomography at the previous hospital. Emergency selective angiography revealed that the pseudoaneurysm arose from the left gastroepiploic artery branching from the splenic artery. Trans-arterial embolization of the left gastroepiploic artery through the splenic artery was successfully performed. Elective distal pancreatectomy and splenectomy with regional lymph node dissection combined with partial resection of the stomach was performed 3 weeks after coil embolization. Pathological examination revealed a moderately differentiated tubular adenocarcinoma in the pancreatic body with regional lymph node metastasis and revealed the pseudoaneurysm rupturing into the pancreatic pseudocyst. The patient has experienced no tumor recurrence or metastasis during 1 year of follow-up., Conclusions: Spontaneous rupture of a pseudoaneurysm is a rare and potentially lethal complication of a pancreatic pseudocyst. Most affected patients have a history of alcoholism and suffer from acute or chronic pancreatitis. To our knowledge, this is the first reported case of a hemorrhagic pancreatic pseudocyst complicating obstructive pancreatitis due to pancreatic cancer.

A man in his 60s was admitted for the treatment of advanced cervical esophageal cancer with metastasis to the lymph nodes and advanced tongue cancer with metastasis to the lymph nodes. Esophageal cancer was suspected to have invaded the trachea. The tongue cancer was located on the left side and had invaded beyond the median line of the tongue. Both cancers were pathologically diagnosed as squamous cell carcinomas. Therefore, it was determined that pharyngo-laryngo- esophagectomy and total glossectomy were required prior to the treatment. However, after 2 courses of docetaxel/cisplatin/ 5-FU combined induction chemotherapy, both cancers remarkably decreased; consequently, an esophagectomy to preserve laryngeal function and partial glossectomy could be performed simultaneously. The patient is well without recurrence 1 year post-surgery.

Background: Adenosquamous carcinoma of the ampulla of Vater is extremely rare, and its clinicopathological features are limited and described in few previous case reports. Here, we report curative resection of adenosquamous carcinoma of the ampulla of Vater at an early stage., Case Presentation: An 81-year-old woman was referred to our hospital for investigation of the frequent elevation of hepatic and biliary enzymes and dilatation of the intrahepatic bile ducts. Preoperative examinations revealed an exposed reddish tumor in the ampulla of Vater, which was diagnosed on biopsy to be adenocarcinoma with squamous cell carcinoma component. Pylorus-preserving pancreaticoduodenectomy with regional lymph node dissection was performed. Pathological examinations revealed the presence of two malignant components in the lesion, including poorly differentiated tubular adenocarcinoma and squamous cell carcinoma, without invasion beyond the sphincter of Oddi or into the duodenal submucosa. These squamous cell carcinoma and adenocarcinoma components in the tumor comprised approximately 30 and 70% of the lesion, respectively. No metastasis into regional lymph nodes was observed, and the patient experienced no tumor recurrence or metastasis until 20 months after surgery., Conclusion: We identified only six reported cases of adenosquamous carcinoma of the ampulla of Vater in the English literature, and all of these patients died of recurrence within 14 months after surgery. To the best of our knowledge, this is the first report of adenosquamous carcinoma of the ampulla of Vater that was curatively resected at an early stage. Although more number of studies on clinicopathological findings are required to determine the appropriate surgical indication, we suggest that surgery remains the mainstay therapy for adenosquamous carcinoma of the ampulla of Vater detected at an early stage.

Persistent sciatic artery (PSA) is a rare congenital anomaly that is frequently complicated by atherosclerotic changes, such as occlusion and aneurysmal formation. This report describes a case of a chronic total occlusion (CTO) of a unilateral, complete-type PSA in the right thigh of a 74-year-old woman that was treated successfully with endovascular angioplasty and stent placement. Within 3 months, however, a PSA aneurysm developed in the gluteal region. This aneurysm was repaired endovascularly through placement of a stent graft. To the authors' knowledge, rapid formation of a PSA aneurysm and successful endovascular treatment of both CTO of a PSA and of a PSA aneurysm have not been reported previously., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Ectopic cervical thymoma is an extremely rare tumor thought to arise from ectopic thymic tissue caused by the aberrant migration of the embryonic thymus. We present the case of a 44-year-old woman with an ectopic cervical thymoma located in the carotid triangle. A computed tomography (CT) scan detected a mass in her right carotid triangle. On an unenhanced scan, the tumor showed homogeneous isodensity compared with muscles, and neither fat nor calcification was detected. A contrast-enhanced CT image obtained during the arterial phase showed intratumoral septa, while an image obtained during the parenchymal phase showed cystic changes within the mass. The patient underwent a surgical resection. A histological study enabled a diagnosis of type AB thymoma in which foci with the features of type A thymoma are admixed with foci rich in lymphocytes. This subtype is a benign tumor with a good prognosis. Ectopic cervical thymoma should be included in the differential diagnosis of solid masses located in the carotid triangle when the CT findings are typical of a thymoma.

We performed transposed brachiobasilic arteriovenous fistula (TBBAVF) in 24 patients from January 2006 to August 2010. The operative time was 90-210 minutes (mean: 136 minutes). All patients had edema of an upper extremity and 2 patients had wound complications. Major complications were not seen. The primary patency rates at one and two years were 89.7% and 69.0%, respectively. The secondary patency rates at one and two years were 95.7% and 73.6%, respectively. TBBAVF has good primary and secondary patency rates with few severe complications. (English Translation of Jpn J Phlebology 2011; 22: 33-38.).

Surgery was performed on a 53-year-old male patient with a painful mass in front of the elbow. The mass originally occurred after needle insertion during a routine health checkup and grew in size during a 1-year period. Intravenous tumor with arterio-venous fistula was diagnosed, and it was resected. Histopathological diagnosis of intravenous lobular capillary hemangioma was made. Occurrence of this tumor after a routine health checkup is rare. The etiology of this tumor occurring simultaneously with arteriovenous fistula is discussed.

Rupture of an expanded polytetrafluoroethylene (ePTFE) vascular graft is rare. We report a nonanastomotic pseudoaneurysm associated with complete disruption of an ePTFE graft that occurred 6 years after an axillofemoral bypass. The 81-year-old patient had undergone neither trauma nor infection. The aneurysmal segment was resected, and a new ePTFE graft was interposed. The patient recovered uneventfully and was well 4 years later. Histologic analysis revealed a torn graft edge, consistent with a rupture due to excessive force, but scanning electron microscopy showed that the internal structure of the prosthesis was intact. The cause of the midgraft rupture remains unknown., (Copyright © 2012 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.)

Stent-graft infections after endovascular aneurysm repair are rare but can have devastating consequences. Open surgery to treat such infections is associated with considerable morbidity and mortality. Removal of the stent-graft is technically challenging, especially when it has a suprarenal fixation. Several in situ reconstructions have been described, with varying results. We report a case in which a Zenith stent-graft became infected after endovascular aneurysm repair to treat an abdominal aortic aneurysm and blue toe syndrome. The endoprosthesis was removed completely, and in situ reconstruction was performed successfully and without complications by using a rifampin-soaked Dacron graft., (Copyright © 2011 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.)

A 14-year-old girl had massive bleeding from a Dieulafoy lesion of the ileum. A preoperative dynamic computed tomography scan detected the point of bleeding. Selective arteriography with embolization using microcoils could not stop the bleeding, but the microcoils were useful as markers of the location of the bleeding point. The position of the microcoils was confirmed by intraoperative fluoroscopy. A partial resection of the ileum that included the lesion was performed. The pathologic finding was Dieulafoy lesion of the ileum. Dieulafoy lesion is a rare condition that usually presents in the stomach. Dieulafoy lesion of the ileum is extraordinarily rare, and to our knowledge, this is only the second case report of an ileal lesion in a child., (Copyright © 2011 Elsevier Inc. All rights reserved.)

A rare case of primary non-Hodgkin's lymphoma of the main hepatic duct junction is reported. A 71-year-old man was admitted for treatment of obstructive jaundice. Radiological examination revealed stenosis of the main hepatic duct junction. Biliary drainage was not necessary because total bilirubin decreased spontaneously. A left hepatic and caudate lobectomy, combined with resection of bile ducts and lymph node dissection, was performed with the preoperative diagnosis of cholangiocarcinoma of the main hepatic duct junction. Macroscopic examination of the resected specimen revealed tumorous growth in the main hepatic duct junction. Histological and immunochemistry findings disclosed a mucosa-associated lymphoid tissue (MALT) lymphoma. The patient received three courses of combination chemotherapy [cyclophosphamide, doxorubicin, vincristine and prednisolone (CHOP)], and there was no evidence of recurrence 45 months after the surgery. Although primary non-Hodgkin's lymphoma of the main hepatic duct junction is extremely rare and difficult to diagnose preoperatively, aggressive surgery followed by chemotherapy, as here, is a possible curative option.

We report a case of cecoanal intussusception caused by cecum cancer in a 29-year-old woman. The patient presented to our hospital with a mass protruding from the anus. We manually pushed the mass back into the rectum and performed a gastrograffin enema, which showed a cup-shaped filling defect in the rectum. The defect was moved back to oral side with the pressure of the enema, revealing a tumor originating in the cecum. Colonoscopy showed a protrusion, 5 x 3 cm in size, in the cecum. Laparotomy confirmed that the tumor originated at the bottom of the appendix in the cecum. We performed partial resection of the cecum containing the tumor and appendix. The pathological finding was submucosal adenocarcinoma in adenoma. Cecoanal intussusception is extremely rare and, to our knowledge, this adult case represents the first report documented in the world scientific literature.

Segmental arterial mediolysis (SAM) is a rare, nonatherosclerotic, noninflammatory arteriopathy. A 52-year-old man with sudden hemiparesis of the right side was found to have an aneurysm of the left internal carotid artery and concomitant multiple aneurysms of the extrahepatic, celiac, and superior mesenteric arteries. Reconstructive operations using autologous vein graft were performed to treat the aneurysms. The histopathology analyses of resected arterial and aneurysmal specimens showed characteristics consistent with SAM. To our knowledge, a successfully treated case of SAM affecting both the carotid artery and visceral arteries has not previously been described.

Recent progress of molecular biology has elicited the pathogenesis of arterial and venous thrombosis at the cellular level. The pathogenesis, as well as the etiology of the sequelae, has become clear to be closely relevant to inflammatory cytokines and growth factors such as tumor recrosis factor (TNF) alpha, interleukin-1 beta, or vascular endothelial growth factor (VEGF). From this point of view, the anti-cytokine or the anti-growth factor therapy including the use of some proteins, antibodies, drugs, and gene delivery systems has every possibility of improving the therapeutic outcome for the thrombosis.

Near-infrared spectroscopy (NIRS) is a noninvasive biomeasurement system with rays in the near-infrared region that possess high permeability to biological tissues. NIRS was applied to liver allografts undergoing rejection in rats treated with deoxyspergualin (DSG) or tacrolimus (FK506). The nitrosyl hemoglobin (Hb) levels detected in the liver grafts increased 3 days and 5 days after grafting in both allogeneic and syngeneic transplantation. The levels on day 8 remained high in the allogeneic graft, but markedly decreased in the syngeneic graft. Although the serum levels of nitrite and nitrate were extremely low 8 days after grafting in allografted recipients treated with DSG or FK506, the nitrosyl-Hb level in DSG-treated graft was much higher than that in FK506-treated graft. There was no significant difference in survival time between DSG-treated and FK506-treated recipients. In conclusion, DSG and FK506 have a different effect on NO production in allografted liver with ongoing rejection, and circulating nitrite and /nitrate levels do not reflect the local levels of NO in the graft.

FTY720 induces apoptosis, specifically in lymphocytes, and prolongs allograft survival in rats and dogs. The purpose of this study was to define an effective range of FTY720 doses that could be combined with a suboptimal dose (10 mg/kg) of cyclosporin for canine kidney allograft recipients. The combination significantly prolonged allograft survival in all groups receiving FTY720 at a dose of 0.1, 0.3, 1.0, or 3.0 mg/kg. None of the recipients died due to notable side effects of the drug. In peripheral blood, the number of lymphocytes was extremely low, whereas the percentage of granulocytes increased during FTY720 administration. No significant difference in cyclosporin trough levels was observed between the cyclosporin-alone group and the combination groups. We conclude from the present study that FTY720 has a potent effect at an extremely low dose and a wide therapeutic window when combined with cyclosporin in canine kidney transplants.

A 55-year-old male consulted a local doctor with the complaint of epigastralgia. Examination of the upper gastrointestinal tract revealed gastric cancer (Borrmann Type II) and he was referred to our hospital for operation. A few lymph nodes were palpable in the left supraclavicular fossa, and the biopsy of those lymph nodes revealed metastatic adenocarcinoma. The CT scan of the abdomen showed enlargement of paraaortic lymph nodes. Then, the patient was determined inoperable (T3, N4, H02 P01, M1 stage IVb). He was treated as an outpatient with UFT-E (300 mg/day, orally), Krestin (PSK 3.0 g/day, orally) and Mitomycin C (MMC 6 or 8 mg once a week, intravenously repeated interval of 4 weeks). The total dose of UFT-E, PSK and MMC was 219 g, 1,095 g and 136 mg, respectively. One month later, lymph nodes in the supraclavicular fossa disappeared, and the lesion in the stomach completely responded. We have followed the patient for more than one year. He visits our the outpatient department and has kept working until now.

In the present study, we examined the immunosuppressive effect of a new drug, FTY720, on small bowel transplantation (SBT) in rats. Grafts from (LEW x BN) F1-to-LEW rats treated with FTY720 at 0.5 mg/kg from day 0 to 14 post-SBT survived significantly longer than untreated grafts. In addition, the administration of FTY720 combined with cyclosporin (CyA; 5 mg/kg per day) had a synergistic effect on allograft survival. The graft-versus-host reaction (GVHR) that occurred in the LEW-to-F1 rats was markedly reduced after the administration of FTY720. FTY720 combined with a low dose of CyA completely abrogated GVHR without any adverse reaction. FTY720 treatment resulted in a significant decrease in the number of lymphocytes in the peripheral blood and the spleen, but the number of peripheral neutrophils was unchanged. Thus, FTY720 would appear to be an ideal drug to combine with CyA in order to control the immune reaction after SBT.

A novel immunosuppressant, FTY720, induces a rapid and marked decrease of peripheral lymphocytes, and prolong allograft survival in rats. Its mechanism of action is mediated by apoptotic cell death. In this study, we determined the time-related changes in the numbers of total lymphocytes, and the ratios of lymphocyte subpopulations in peripheral blood and lymphomyeloid organs in rats after the single oral administration of FTY720 (10 mg/kg), comparing with the effects of cyclophosphamide (80 mg/kg, ip). Total number of peripheral lymphocytes decreased significantly 3 h after the administration of the drug, while that of polymorphonuclear cells increased. T-cells were markedly decreased in number and reached a minimum of 2.3% of the control 3 days after the treatment, while B-cells reached 19.7%. T-cells decreased in spleen and liver but there was no notable change in thymus, lymph nodes, and bone marrow. The susceptibility of the cells against the drug was variant based on the type and the source of cells in vitro. Polymorphonuclear cells were the most resistant and lymph node cells the most sensitive to FTY720 after 3 h incubation with different concentration of the drug (1, 10,100 mumol/l). When incubated with 10 mumol/l of FTY720, B-cells were significantly higher in viability than the whole T- or CD4-cells. These results demonstrated that FTY720 induces cell death selectively in mature T-lymphocytes, especially CD4-lymphocytes, in peripheral blood without the depression of bone marrow.

Aiming the selection of possible candidates for the reactor cells in a hybrid artificial liver, we investigated the activities of 7-ethoxycoumarin deethylation and ammonia removal in 31 hepatocytes cell lines established from the human, rat, mouse, and chicken, compared with freshly isolated rat hepatocytes. Rat liver homogenate and hepatocytes showed 7-ethoxycoumarin deethylation activity of 0.925 and 1.840 nmol/mg protein/min, respectively. Two human hepatoblastoma cell lines, Hep G2 and HuH 6, showed the activity of 0.190 and 0.027 nmol/mg protein/min, respectively. While the rat hepatocytes efficiently removed added ammonia form the culture medium, no ammonia removal activity was detectable in any cell line with the assay conditions in this study. Ammonia removal activity, possibly catalyzed by the urea cycle, is likely to be harder to restore than the drug metabolizing system in the course of cell immortalization.

A new compound with an immunosuppressive property was purified from culture filtrates of Isaria sinclairii and was chemically modified to FTY720. Rat spleen cells incubated with FTY720 demonstrated features characteristic of apoptosis--such as the absence of surface microvilli, chromatin condensation, and the formation of apoptotic bodies--by electron microscopy, and genemic DNA fragmentation by agarose gel electrophoresis. When FTY720 was administered in liver-allografted rats at a dose of 0.5 mg/kg from day 1 to day 14 after transplantation, the recipients survived significantly longer than the control group. Pretransplant treatment with 5 mg/kg of FTY720 one day before and on the day of grafting induced a remarkable prolongation of recipient survival, and three of 10 recipients survived for longer than 50 days. Furthermore, administration of FTY720 at 5 mg/kg on days 3 and day 4 after grafting also prolonged survival. In canine kidney allografting, a pretransplant 2-day course of FTY720 at 5 mg/kg prolonged graft survival. Daily administration of FTY720 in combination with CsA resulted in a significant prolongation of graft survival in a synergistic manner. In addition, FTY720 appeared to be nontoxic in canine recipients. These results demonstrated that FTY720, having a unique mechanism of action, induces long-term graft acceptance in rat and dog allotransplantation.