ADAMTS13によるvon Willebrand因子の切断増加は、本態性血小板血症患者における後天性von Willebrand症候群の発症に強く寄与する。

Background: Patients with essential thrombocythemia (ET) often experience bleeding associated with acquired von Willebrand syndrome (AVWS) when the platelet count is markedly increased. Objective: We investigated whether von Willebrand factor (VWF) degradation is enhanced in patients with ET. Methods: Seventy patients with ET underwent VWF multimer (VWFM) analysis and measurement of VWF-related parameters. We calculated the VWFM index, defined as the ratio of intensities of a patient's molecular weight-categorized VWFMs, and those of a healthy subject's, using densitometric analysis. VWF degradation product (DP) was measured via ELISA using a monoclonal antibody that specifically recognizes Y1605 at the C-terminal boundary, which is exposed following ADAMTS13-mediated cleavage of the Y1605-M1606 bond of the VWF A2 domain. Results: Patients with higher platelet counts had a significantly reduced high molecular weight (HMW)-VWFM index and an increased VWF-DP: VWF antigen (Ag) ratio compared to those with lower platelet counts. On multivariate analysis, the VWF-DP/ VWF:Ag ratio was an independent predictor of the HMW-VWFM index. Patients who underwent cytoreductive therapy had a significantly higher HMW-VWFM index and lower VWF-DP/ VWF:Ag ratio than those who did not. Among individual patients, there was also a significant increase in the HMW-VWFM index and a decrease in the VWF-DP/ VWF:Ag ratio after cytoreductive therapy compared to pre-therapy values. Conclusion: In patients with ET, an increased platelet count is associated with enhanced cleavage of VWF at the Y1605-M1606 bond, primarily by ADAMTS13, leading to AVWS. Cytoreductive therapy reduces the platelet count, prevents excessive VWF cleavage, and improves VWFM distributions.博士（医学）・甲第881号・令和5年3月15

包括的凝固/線溶動態に基づく敗血症性DIC（播種性血管内凝固）の病態解明

Background: The functional dynamics of coagulation and fibrinolysis in patients with disseminated intravascular coagulation (DIC) vary due to the pathology and severity of various underlying diseases. Conventional measurements of hemostasis such as thrombin-antithrombin complex, plasmin-α2-plasmin-inhibitor complex, and fibrinogen-fibrin degradation products may not always reflect critical pathophysiologic mechanisms in DIC. This article aims to clarify the pathology of sepsis-associated DIC using assessment of comprehensive coagulation and fibrinolysis. Methods: Plasma samples were obtained from 57 patients with sepsis-associated DIC at the time of initial diagnosis. Hemostasis parameters were quantified by clot-fibrinolysis waveform analysis (CFWA) and thrombin/plasmin generation assays (T/P-GA). The results were expressed as ratios relative to normal plasma. Results: CFWA demonstrated that the maximum coagulation velocity (|min1|) ratio modestly increased to median 1.40 (min - max: 0.10 - 2.60) but the maximum fibrinolytic velocity (|FL-min1|) ratio decreased to 0.61 (0 - 1.19). T/P-GA indicated that the peak thrombin (Th-Peak) ratio moderately decreased to 0.71 (0.22 - 1.20), whereas the peak plasmin (Plm-Peak) ratio substantially decreased to 0.35 (0.02 - 1.43). Statistical comparisons identified a correlation between |min1| and Th-Peak ratios (ρ = 0.55, p < 0.001), together with a strong correlation between |FL-min1| and Plm-Peak ratios (ρ = 0.71, p < 0.001), suggesting that CFWA reflected the balance between thrombin and plasmin generation. With |min1| and |FL-min1| ratios, DIC was classified as follows: coagulation-predominant, coagulation/fibrinolysis-balanced, fibrinolysis-predominant, and consumption-impaired coagulation. The majority of patients in our cohort (80.7%) were coagulation-predominant. Conclusion: A pathological clarification of sepsis-associated DIC based on the assessment of coagulation and fibrinolysis dynamics may be useful for the hemostatic monitoring and management of optimal treatment in these individuals.博士（医学）・甲第786号・令和3年3月15日© 2020. Thieme. All rights reserved.This is a non-final version of an article published in final form in "http://dx.doi.org/10.1055/s-0040-1713890

〈Original〉Quality of life of chronic myelogenous leukemia patients following BCR-ABL inhibitor therapy: A multicenter study in Nara Japan using SF-8

[Abstract]Chronic myelogenous leukemia (CML) is caused by chromosomal translocation t (9;22) (q34;q11.2) forming a BCR-ABL fusion gene. Treatment of CML patients with tyrosine kinase inhibitor (TKI) led to a marked improvement in the survival rate. However, when treating CML patients, adverse events of TKI may reduce the QOL. When we were able to use only Imatinib, we continued to use despite adverse events. However, we can now use Dasatinib, Nilotinib, Bosutinib, and Ponatinib. Therefore, to examine the effects of TKI on the QOL of CML patients, we conducted a QOL survey at three major facilities in Nara Prefecture. For the QOL survey, we used SF-8. The results of the survey showed that there was no difference between the pretreatment QOL score and QOL score at the time of the survey. However, the QOL scores showed improved physical functioning, bodily pain, vitality, role-emotional, and mental health summary scores in the TKI switch group. The main reason for switching TKI was adverse events. Therefore, these adverse events reduce the QOL of CML patients. Switching TKI improved the QOL. Presently, five TKI are available, expanding the range of options. When adverse events appear, switching TKI and adverse event management are also important to maintain a patient’s QOL and continue the therapy

Increased cleavage of von Willebrand factor by ADAMTS13 may contribute strongly to acquired von Willebrand syndrome development in patients with essential thrombocythemia

Background: Patients with essential thrombocythemia (ET) often experience bleeding associated with acquired von Willebrand syndrome (AVWS) when the platelet count is markedly increased. Objective: We investigated whether von Willebrand factor (VWF) degradation is enhanced in patients with ET. Methods: Seventy patients with ET underwent VWF multimer (VWFM) analysis and measurement of VWF-related parameters. We calculated the VWFM index, defined as the ratio of intensities of a patient's molecular weight-categorized VWFMs, and those of a healthy subject's, using densitometric analysis. VWF degradation product (DP) was measured via ELISA using a monoclonal antibody that specifically recognizes Y1605 at the C-terminal boundary, which is exposed following ADAMTS13-mediated cleavage of the Y1605-M1606 bond of the VWF A2 domain. Results: Patients with higher platelet counts had a significantly reduced high molecular weight (HMW)-VWFM index and an increased VWF-DP: VWF antigen (Ag) ratio compared to those with lower platelet counts. On multivariate analysis, the VWF-DP/ VWF:Ag ratio was an independent predictor of the HMW-VWFM index. Patients who underwent cytoreductive therapy had a significantly higher HMW-VWFM index and lower VWF-DP/ VWF:Ag ratio than those who did not. Among individual patients, there was also a significant increase in the HMW-VWFM index and a decrease in the VWF-DP/ VWF:Ag ratio after cytoreductive therapy compared to pre-therapy values. Conclusion: In patients with ET, an increased platelet count is associated with enhanced cleavage of VWF at the Y1605-M1606 bond, primarily by ADAMTS13, leading to AVWS. Cytoreductive therapy reduces the platelet count, prevents excessive VWF cleavage, and improves VWFM distributions.博士（医学）・甲第881号・令和5年3月15日This is the peer reviewed version of the following article: [Masayuki Kubo et al. Increased cleavage of von Willebrand factor by ADAMTS13 may contribute strongly to acquired von Willebrand syndrome development in patients with essential thrombocythemia. Journal of Thrombosis and Haemostasis. 2022, 20(7), p.1589-1598.], which has been published in final form at [https://doi.org/10.1111/jth.15717]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.identifier:Journal of thrombosis and haemostasis Vol.20 No.7 p.1589-1598 (2022 Jul)identifier:15387933identifier:http://ginmu.naramed-u.ac.jp/dspace/handle/10564/4113identifier:Journal of thrombosis and haemostasis, 20(7): 1589-159

Allogeneic hematopoietic stem cell transplantation for the treatment of BCR-ABL1-negative atypical chronic myeloid leukemia and chronic neutrophil leukemia: A retrospective nationwide study in Japan

Atypical chronic myeloid leukemia(aCML)and chronic neutrophilic leukemia(CNL)are rare BCR-ABL1 fusion gene-negative myeloid neoplasms with a predominance of neutrophils. Since no standard therapeutic strategy currently exists for these diseases,we retrospectively evaluated the outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for aCML and CNL. Data from 14 aCML and 5 CNL patients as their diagnoses were collected using a nationwide survey. Allo-HSCT was performed between 2003 and 2014. Preconditioning regimens included myeloablative (n = 15),reduced-intensity (n = 3), and non-myeloablative (n = 1) regimens. Transplanted stem cells were obtained from HLA-matched related donors (n = 5) and alternative donors (n = 14). Neutrophil engraftment was successfully achieved in 17 patients. One-year overall survival rates (OS) were 54.4% (95% confidence interval [CI], 24.8 to 76.7%) and 40.0% (95% CI, 5.2 to 75.3%) in patients with aCML and CNL, respectively. Among aCML patients, 1-year OS were 76.2% (95% CI, 33.2 to 93.5%) and 20.0% (95% CI, 0.8 to 58.2%) in patients with <5% myeloblasts (n = 9) and ?5% myeloblasts (n = 5) in peripheral blood before allo-HSCT, respectively. These results suggest that allo-HSCT achieves long-term survival in patients with aCML and CNL. Better pre-transplant management is required to improve the outcomes of aCML patients with ?5% blasts in peripheral blood