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Previously, we reported that a direct thrombin inhibitor melagatran paradoxically increased thrombin generation in human plasma in the presence of thrombomodulin. The aim of this study is to test the hypothesis that melagatran may exert a deleterious effect on tissue-type plasminogen activator (t-PA)-induced fibrinolysis via enhancement of thrombin generation and subsequent activation of thrombin-activatable fibrinolysis inhibitor (TAFI) and factor XIII (FXIII). Clot formation in human plasma containing t-PA and thrombomodulin was induced by tissue factor. The absorbance at 405 nm was measured to obtain clot lysis time. Effects of melagatran and a factor Xa inhibitor edoxaban on clot lysis time were determined. In the presence of thrombomodulin, melagatran significantly prolonged clot lysis time, but edoxaban shortened it. In the absence of thrombomodulin, melagatran did not inhibit fibrinolysis. Prolongation of clot lysis time by melagatran was reversed by activated protein C (which suppressed thrombin generation increased by melagatran) and a TAFIa inhibitor. Melagatran significantly suppressed plasmin generation, while edoxaban significantly increased it. However, both melagatran and edoxaban suppressed FXIII activation. In the clot formed in the presence of melagatran and edoxaban, the fibrin fibre was thin compared with control, showing no clear difference in the clot structures between melagatran and edoxaban. These results indicated that melagatran, not edoxaban, prolonged clot lysis time through the paradoxical enhancement of thrombin generation, and subsequent TAFI activation and inhibition of plasmin generation. Neither FXIII activation nor change in fibrin clot structure contributed to the inhibition of fibrinolysis by melagatran.

Infection increases the risk of thrombosis through the activation of inflammation and coagulation. Edoxaban, a direct oral factor Xa inhibitor, is used for the prevention and treatment of thrombotic diseases. The aim of this study was to determine the effects of edoxaban on microvascular thrombus formation in a rat model of lipopolysaccharide (LPS)-induced coagulopathy. Rats were intravenously injected with 7.5 mg/kg of LPS (Escherichia coli 055:B5). Immediately after LPS injection, the rats were treated with subcutaneous injection of edoxaban. At 2 and 6 h after the injection of LPS, biomarkers of coagulation and organ damages and inflammatory cytokines were measured. Microvascular thrombus formation in organs was evaluated using 125I-fibrinogen (human) or by the pathological analysis. Mortality was examined 24 h after LPS injection. After the injection of LPS, D-dimer and thrombin-antithrombin complex increased and platelet numbers decreased, indicating the activation of coagulation. Microvascular thrombi were found in the liver. Markers of liver injury (aspartate aminotransferase and alanine aminotransferase) also increased. Treatment with edoxaban attenuated the changes in the coagulation markers and microvascular thrombus formation in the liver. Edoxaban suppressed the increase in the liver injury markers and reduced the mortality. Edoxaban did not affect the levels of inflammatory cytokines. In conclusions, edoxaban significantly inhibited the activation of coagulation, the formation of microvascular thrombus in the liver and the liver damage, and reduced mortality in rats injected with LPS. These results suggest that the FXa inhibition by edoxaban might be a beneficial therapy for the management of infection-associated thrombosis.

Patients with diabetes are known to have high salivary glucose levels. But the mechanisms are still unclear. We hypothesized that the topological changes of glucose transporters affect the salivary glucose level.We used adult Goto-Kakizaki (GK) rats, an animal model of advanced diabetes, and Wistar rats as a control, with or without glucose load. The sections of salivary glands from the animals were processed for standard histological, immunohistochemical, and immunofluorescent staining.Parotid acinar cells of GK rats appeared like mucous filled with low-eosin-stained granules and possessing a flat nucleus located basally, whereas those of Wistar rats appeared as a typical serous gland with eosin-rich cytoplasm and a spherical nucleus. Cytoplasmic granules of GK rat parotid acinar cells showed no reaction of polysaccharide staining. In acinar cell cytoplasm of GK rats, intense GLUT1 immunoreactivity was observed compared to Wistar rats. By double immunostaining for GLUT1 and Golgi apparatus-specific markers, it was determined that GLUT1 was localized to the Golgi apparatus. By glucose loading in starved GK rats, the distribution of GLUT1-immunoreactive signals was spread out clearly from the apical side of the nucleus to the basolateral side.In rat model of diabetes, highly localized GLUT1 at Golgi apparatus in acinar cells seems to increase taking up cytoplasmic glucose to form exocytotic vesicles. This phenomenon may transform parotid glands from serous to mucous-like and result in saccharide-rich saliva.

We report a pediatric case aged 10 years with Granulicatella adiacens-associated chronic mandibular osteomyelitis. The causative pathogen was uncertain because polymicrobial species were detected from the bacterial culture in bone marrow fluid. In contrast, G. adiacens was predominantly identified in the clone library analysis of the bacterial 16S rRNA gene sequence. Vancomycin to which G. adiacens was reported to be susceptible was not administrated sufficiently to this patient because of its adverse event, whereas linezolid and ciprofloxacin was alternatively effective for the treatment of chronic mandibular osteomyelitis.

In adults, meningiomas occasionally display aggressive behavior and may occasionally metastasize. By contrast, pediatric meningiomas are rare, and there is limited information regarding their clinical characteristics, treatment and prognosis. We herein report the case of a 3-year-old boy with anaplastic meningioma with a history of local recurrence and late pulmonary metastasis. At diagnosis, a 70-mm mass lesion in was identified in the right frontal lobe, with intratumoral hemorrhage. The tumor was attached to the falx cerebri and was completely resected. The histological diagnosis was anaplastic meningioma, World Health Organization grade III. Two months after the surgery, the meningioma recurred at the same site. Although the patient received radiotherapy after a second operation, the tumor metastasized to the lung and pleura 8 months after the initial operation. The metastasis was resistant to treatment, even after gross total resection, and the effectiveness of further radiotherapy was limited. The patient succumbed to the disease 1 year and 4 months after the initial diagnosis. The findings of the present case and a review of the relevant literature suggest that recurrence and metastasis of meningiomas are difficult to predict. Therefore, such patients should be carefully monitored throughout the follow-up period.

A direct oral anticoagulant, edoxaban, is as effective as vitamin K antagonists for the treatment of venous thromboembolism (VTE). However, the mechanism underlying the treatment effect on VTE remains to be determined. The aims of this study were to evaluate the effect of edoxaban on tissue plasminogen activator (t-PA)-induced clot lysis in human plasma and to determine the roles of plasmin and thrombin-activatable fibrinolysis inhibitor (TAFI) in the profibrinolytic effect by edoxaban. Pooled human normal plasma or TAFI-deficient plasma (containing 180 ng/mL t-PA and 0.1 nM thrombomodulin) was mixed with edoxaban or an activated TAFI inhibitor, potato tuber carboxypeptidase inhibitor (PCI). Clot was induced by adding tissue factor and phospholipids. Clot lysis time and plasma plasmin-α2 antiplasmin complex (PAP) concentration were determined. Clot structure was imaged with a scanning electron microscope. In normal plasma, edoxaban at clinically relevant concentrations (75, 150, and 300 ng/mL) and PCI significantly shortened clot lysis time. PCI increased PAP concentration and a correlation between PAP concentration and percent of clot lysis was observed. Edoxaban also dose-dependently elevated PAP concentration. In TAFI-deficient plasma, the effects of edoxaban and PCI on clot lysis and PAP concentration were markedly diminished as compared with normal plasma. Fibrin fibers were thinner in clots formed in the presence of edoxaban. In conclusion, edoxaban at clinically relevant concentrations accelerates t-PA-induced fibrinolysis via increasing plasmin generation in human plasma. The effects of edoxaban is mainly dependent on TAFI. The profibrinolytic effect of edoxaban might contribute to the efficacy for the treatment of VTE.

In addition to platelet aggregation, coagulation activation is considered to be involved in arterial thrombosis. In this study, we determined antithrombotic effects of edoxaban, an oral factor Xa (FXa) inhibitor, as both a monotherapy and in combination with antiplatelet agents in a rat model of arterial thrombosis. We further examined its effects on a procoagulant biomarker and bleeding. Arterial thrombosis was induced by topical application of 15% ferric chloride to rat abdominal aortas. Bleeding time was measured by a tail incision method. Edoxaban, clopidogrel, and aspirin were orally administered 30min, 4h, and 2h before thrombus or bleeding induction. As a biomarker of coagulation activation, plasma thrombin-antithrombin complex (TAT) was measured. Edoxaban dose-dependently prevented arterial thrombosis in a manner comparable to clopidogrel and aspirin. The combination of edoxaban plus clopidogrel or edoxaban plus aspirin significantly potentiated the antithrombotic effects compared with these drugs alone. The combination of edoxaban and clopidogrel was more potent than clopidogrel and aspirin. Plasma TAT concentration was elevated after thrombus induction and suppressed by edoxaban and clopidogrel, but not by aspirin, suggesting P2Y12 receptor-mediated platelet procoagulant activity. Bleeding time was prolonged by the coadministration of edoxaban and clopidogrel, but not by edoxaban and aspirin. In conclusion, the present study demonstrates that the monotherapy with edoxaban and combination therapy with edoxaban plus clopidogrel or edoxaban plus aspirin are promising options for the prevention of arterial thrombosis as effective as the standard antiplatelet agents; however, a combination of edoxaban and clopidogrel increased the risk of bleeding.

Vascular injury activates the coagulation cascade. Some studies report that coagulation factor Xa and thrombin are implicated in proliferation of vascular smooth muscle cells and neointimal hyperplasia after vascular injury. The aim of this study was to determine the effect of an oral direct factor Xa inhibitor, edoxaban, on neointimal hyperplasia following the carotid artery injury in apolipoprotein E (ApoE)-deficient mice. Vascular injury was induced by the application of 10% ferric chloride to the carotid artery for 3 min in ApoE-deficient mice. After vascular injury, all animals were fed with high-cholesterol chow for 6 weeks. Edoxaban at 15 mg/kg was orally administered to the mice 1 h before (n = 10) or 1 h after (n = 9) ferric chloride injury, and thereafter 10 mg/kg edoxaban was orally administered b.i.d. for 6 weeks. Thrombus formation and neointimal hyperplasia were evaluated. Treatment with 15 mg/kg edoxaban before vascular injury almost completely inhibited thrombus formation, and following chronic administration of edoxaban significantly suppressed neointimal hyperplasia. In the mice treated with edoxaban after vascular injury, there was wide interindividual variability. In some mice (four out of nine) the neointimal hyperplasia was inhibited like in edoxaban-pretreated mice, but there was no statistical difference compared with control. This study demonstrated that inhibition of the coagulation and thrombosis by edoxaban ameliorated neointimal hyperplasia caused by vascular injury and high-cholesterol diets in ApoE-deficient mice. This suggests that factor Xa has a crucial role in the formation of neointima following vascular injury.The abstract should be followed by 3-4 bullet points that highlight major findings. The final bullet point should emphasize future directions for research.

Aim To clarify growth patterns, spatial distribution and risk factors of cerebral white matter hyperintensity (WMH) lesions on magnetic resonance imaging. Methods We analyzed volumes of cerebral WMH lesions in those who underwent brain magnetic resonance imaging as a hospital-based health check-up in 2012 and 2013 by using a computational quantitative image analysis software (Software for NeuroImage Processing in Experimental Research). After excluding subjects not suitable for volumetric analyses because of pathological brain conditions, a total of 1047 healthy participants (mean age 56.6 years) were included for the analyses. First, the relationship of computational volumetry and conventional qualitative visual evaluation by Shinohara grading was evaluated. Volumes of WMH lesions were analyzed according to age and the different cerebral lobes. Finally, clinical risk factors associated with WMH lesions were assessed. Results Volumes of WMH lesions were significantly correlated with Shinohara grading (P

We report the long-term morbidity and mortality of 105 pediatric patients who developed chronic graft-versus-host disease (cGVHD) after allogeneic hematopoietic stem cell transplantation (HSCT). According to the consensus criteria of the National Institutes of Health, the global severity of cGVHD was mild in 26 patients (25%), moderate in 30 patients (29%), and severe in 49 patients (47%). Patients with severe cGVHD had a significantly lower cumulative incidence of cGVHD remission and higher probability of continuing cGVHD at 8 years from cGVHD diagnosis compared with those with mild or moderate cGVHD. The 10-year cumulative incidence of nonrelapse mortality in severe cGVHD patients was significantly higher and the probability of disease-free survival was significantly lower than those among patients with mild and moderate cGVHD. Of the 59 patients who survived for more than 5 years, 20 (34%) (4 with moderate and 16 with severe cGVHD) had persistent functional impairment caused by cGVHD with a Karnofsky/Lansky performance score of 90% in 3 patients, 80% in 4 patients, and below 70% in 13 patients at the time of relapse, death, or last follow-up. Better therapeutic strategies are needed to lower the incidence of severe cGVHD, considering the longer life expectancy of pediatric HSCT survivors.

Edoxaban is an oral and direct activated factor X inhibitor. In this study, the acute treatment effect of edoxaban on venous thrombosis is investigated in rats by single and multiple administrations, and compared to the conventional parenteral anticoagulants, enoxaparin and fondaparinux. Venous thrombus was induced in the inferior vena cava by partial stenosis plus topical application of 10% ferric chloride for 5min. After 1-h thrombus maturation, oral edoxaban and subcutaneous enoxaparin and fondaparinux were given. In the single administration experiment, thrombus weight was measured 1 or 4h after thrombus induction. In the multiple administration experiments, edoxaban was orally administered once daily (QD) and twice daily (BID) for 3 days. In the single administration experiment, oral administration of edoxaban (3.0 and 10mg/kg) 1h after thrombus formation significantly regressed the venous thrombus compared to the thrombus at 1h after thrombus formation. Similarly the significant venous thrombus regression was observed with enoxaparin (10mg/kg) and fondaparinux (0.30-3.0mg/kg). In the multiple administration experiment, both QD and BID administration of edoxaban at daily doses of 5 and 10mg/kg exerted significant treatment effects. QD administration of edoxaban including lower doses (1-10mg/kg) significantly reduced thrombus weight. Edoxaban administered QD and BID was effective in the treatment of venous thrombosis, and the treatment effect of edoxaban was comparable to the conventional parenteral anticoagulants. These data demonstrate the potential of edoxaban as an oral anticoagulant in the acute treatment of venous thromboembolism.

In this study, oxytocin receptors (OTRs) in the islets of Langerhans were detected using real-time RT-PCR and immunohistochemical technique. Indeed, OTR mRNA was expressed in the rat pancreas. Double immunohistochemical staining for OTR and either glucagon or insulin demonstrated their co-localization in A-cells or B-cells, respectively. OTR-immunoreactivity in A-cells was stronger than that of B-cells. All A-cells and 94.8% of B-cells were OTR-immunoreactive. We reveal the statistically significant relations of OTR with A-cells and B-cells in the islets of Langerhans. This is the first demonstration of the OTR localization in the islets of Langerhans immunohistochemically. It suggests that oxytocin (OT) is involved in the release of insulin and glucagon.

To clarify growth patterns, spatial distribution and risk factors of cerebral white matter hyperintensity (WMH) lesions on magnetic resonance imaging.We analyzed volumes of cerebral WMH lesions in those who underwent brain magnetic resonance imaging as a hospital-based health check-up in 2012 and 2013 by using a computational quantitative image analysis software (Software for NeuroImage Processing in Experimental Research). After excluding subjects not suitable for volumetric analyses because of pathological brain conditions, a total of 1047 healthy participants (mean age 56.6 years) were included for the analyses. First, the relationship of computational volumetry and conventional qualitative visual evaluation by Shinohara grading was evaluated. Volumes of WMH lesions were analyzed according to age and the different cerebral lobes. Finally, clinical risk factors associated with WMH lesions were assessed.Volumes of WMH lesions were significantly correlated with Shinohara grading (P 0.001). WMH lesions significantly enlarged with aging (P 0.001) except for the occipital lobe, especially in participants aged 50 years or older. Age and systolic blood pressure were significantly related to volumes of WMH lesions in all the lobes, whereas diastolic blood pressure was not related only in the occipital lobe.Based on computational quantitative volumetric analyses, cerebral WMH lesions increased with age, and were associated with blood pressure. However, the occipital lobe was the only exception to these findings.

of this photoreaction, a free radical involvement is implicated (11). In addition, in the process of the mechanistic studies, we found that 2-nitro-3-methylimidazo[4,5-/lquinoline is formed on UVA irradiation of a mixture of 2-amino-3-met hylimidazo[4,5-/lquinoline and N-nitrosodimethylamine, a phenomenon suggesting that oxidative species are produced in UVA plus nitrosamines (12). It is known that 8-oxodeoxyguanosine (8-oxodG) in DNA, a common lesion in oxidized DNA, results in mutations (13). Based on these considerations, we decided to explore the possibility that NMOR plus UVA might form 8-oxodG in DNA leading to mutations. In this study, we treated M13mp2, a phage with singlestranded DNA, with NMOR plus UVA, and analyzed the spectrum of mutations induced in the lacZa. region. We also measured the formation of 8-oxodG in the DNA of the treated phage. Furthermore, we have constructed a derivative of Escherichia coli defective in 8-oxodG DNA glycosylase activity (mutM) and investigated the effect of the repair deficiency toward the mutations caused by NMOR plus UVA.