エミシズマブは凝固第VIII因子と同様にフィブリン構造およびその安定性を向上させる

Introduction: Emicizumab is an antifactor (F)IXa/FX bispecific antibody, mimicking FVIIIa cofactor function. Emi prophylaxis effectively reduces bleeding events in patients with haemophilia A. The physical properties of emicizumab-induced fibrin clots remain to be investigated, however. Aim: We have investigated the stability and structure of emicizumab-induced fibrin clots. Methods: Coagulation was initiated by activated partial thromboplastin time (aPTT) trigger and prothrombin time (PT)/aPTT-mixed trigger in FVIII-deficient plasma with various concentrations of emicizumab or recombinant FVIII. The turbidity and stability of fibrin clots were assessed by clot waveform and clot-fibrinolysis waveform analyses, respectively. The resulting fibrin was analysed by scanning electron microscopy (SEM). Results: Using an aPTT trigger, the turbidity was decreased and the fibrinolysis times were prolonged in the presence of emicizumab dose-dependently. Scanning electron microscopy imaging demonstrated that emicizumab improved the structure of fibrin network with thinner fibres than in its absence. Although emicizumab shortened the aPTT dramatically, the nature of emicizumab-induced fibrin clots did not reflect the hypercoagulable state. Similarly, using a PT/aPTT-mixed trigger that could evaluate potential emicizumab activity, emicizumab improved the stability and structure of fibrin clot in a series of experiments. In this circumstance, fibrin clot properties with emicizumab at 50 and 100 µg/mL appeared to be comparable to those with FVIII at ~12 and ~24-32 IU/dL, respectively. Conclusion: Emicizumab effectively improved fibrin clot stability and structure in FVIII-deficient plasma, and the physical properties of emicizumab-induced fibrin clots were similar to those with FVIII.博士（医学）・甲第787号・令和3年3月15日© 2020 John Wiley & Sons Ltd.This is the peer reviewed version of the following article: https://onlinelibrary.wiley.com/doi/10.1111/hae.13961, which has been published in final form at https://doi.org/10.1111/hae.13961. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions

The effect of periodontal treatment for atherosclerotic indicator:cardio ankle vascular index(CAVI)

Independent from hyperlipidemia, hypertension, diabetes mellitus, smoking, a classical risk factor for arteriosclerosis, it has been shown that various types of chronic inflammationmay be involved in the development of arteriosclerosis. As a chronic inflammation, theprevalence rate of periodontal disease is reported to be about 80% at the age of 30 to 50years, and about ₉0% at the age of 60ʼs. In this study, cardio ankle vascular index (CAVI),a vascular function test, was measured as an indicator of arteriosclerosis before and aftertreatment of periodontal disease. As a result, it was revealed that CAVI statistically significantly decreased by treatment of periodontal disease. Further studies are needed in th

Surface properties of dental zirconia ceramics affected by ultrasonic scaling and low-temperature degradation

Zirconia (3Y-TZP) dental prostheses are widely used in clinical dentistry. However, the effect of ultrasonic scaling performed as a part of professional tooth cleaning on 3Y-TZP dental prostheses, especially in conjunction with low-temperature degradation (LTD), has not been fully investigated. The present study aimed to evaluate the influence of ultrasonic scaling and LTD on the surface properties of 3Y-TZP in relation to bacterial adhesion on the treated surface. 3Y-TZP specimens (4 × 4 × 2 mm) were polished and then subjected to autoclaving at 134˚C for 100 h to induce LTD, followed by 10 rounds of ultrasonic scaling using a steel scaler tip for 1 min each. Surface roughness, crystalline structure, wettability, and hardness were analyzed by optical interferometry, X-ray diffraction analysis, contact angle measurement, and nano-indentation technique, respectively. Subsequently, bacterial adhesion onto the treated 3Y-TZP surface was evaluated using Streptococcus mitis and S. oralis. The results demonstrated that the combination of ultrasonic scaling and LTD significantly increased the Sa value (surface roughness parameter) of the polished 3Y-TZP surface from 1.6 nm to 117 nm. LTD affected the crystalline structure, causing phase transformation from the tetragonal to the monoclinic phase, and decreased both the contact angle and surface hardness. However, bacterial adhesion was not influenced by these changes in surface properties. The present study suggests that ultrasonic scaling may be acceptable for debridement of 3Y-TZP dental prostheses because it did not facilitate bacterial adhesion even in the combination with LTD, although it did cause slight roughening of the surface