暂无摘要。

UNASSIGNED: Transplant-associated thrombotic microangiopathy (TA-TMA) is a fatal complication of hematopoietic stem cell transplantation and is characterized by severe thrombocytopenia, hemolytic anemia, and organ dysfunction. In response to several possible triggers, dynamic multimetric change in von Willebrand factor (VWF) may contribute to inducing microthrombi in circulation in TA-TMA.
UNASSIGNED: By performing VWF multimer analysis and measuring VWF-degradation product (DP), we unraveled the relationship between multimeric changes in circulating VWF and the pathogenesis of TA-TMA.
UNASSIGNED: This study analyzed 135 plasma samples from 14 patients who underwent allogeneic hematopoietic stem cell transplantation at a single institute. VWF-associated markers, namely VWF:antigen (VWF:Ag), VWF-DP/VWF:Ag ratio, VWF:ristocetin cofactor activity, VWF:ristocetin cofactor activity/VWF:Ag ratio, and ADAMTS13 activity, were analyzed in these samples collected every 7 days.
UNASSIGNED: There were 2 patients with definite thrombotic microangiopathy (TMA) and 6 patients who presented with probable TMA that did not progress to definite TMA. Each plasma sample was classified into 3 groups: definite TMA, probable TMA, and non-TMA. VWF multimer analysis showed the absence of high-molecular-weight VWF multimers in probable TMA, whereas the appearance of unusually large VWF multimers was observed in definite TMA. The median value of the VWF-DP/VWF:Ag ratio in probable TMA was elevated to 4.17, suggesting that excessive cleavage of VWF multimers by VWF cleaving enzyme, ADAMTS13, resulted in the loss of high-molecular-weight VWF multimers.
UNASSIGNED: During the transition from probable to definite TMA, drastic VWF multimer changes imply a switch from bleeding to thrombotic tendencies. Extensive VWF-DP and VWF multimer analyses provided novel insights.

Endothelial cells deliver a vital contribution to the maintenance of hemostasis by constituting an anatomical as well as functional barrier between the blood and the rest of the body. Apart from the physical barrier function, endothelial cells maintain the hemostatic equilibrium by their pro- and anticoagulant functions. An important part of their procoagulant contribution is the production of von Willebrand factor (VWF), which is a carrier protein for coagulation factor VIII (FVIII) and facilitates the formation of a platelet plug. Thus, VWF is indispensable for both the primary and secondary hemostasis, which is exemplified by the bleeding disorder Von Willebrand Disease (VWD) that results from qualitative or quantitative deficiencies in VWF. A cellular model that was found to accurately reflect the endothelium and its secretory organelles are endothelial colony forming cells (ECFCs), which can be readily isolated from peripheral blood and constitute a robust ex vivo model to investigate the donor\'s endothelial cell function. This review summarizes some of the valuable insights on biology of VWF and pathogenic mechanisms of VWD that have been made possible using studies with ECFCs derived from patients with bleeding disorders.

Objective: To investigate the clinicopathological features and differential diagnosis of breast angiomatosis. Methods: Six cases of breast angiomatosis diagnosed at the Department of Pathology, the Seventh Medical Center, People\'s Liberation Army General Hospital and the Department of Pathology, Dongzhimen Hospital, Beijing University of Chinese Medicine from January 2011 to December 2023 were evaluated and reviewed. Results: All patients were female with an average age of 46 years at presentation, ranging from 25 to 62 years. The most common clinical presentation was a palpable unilateral breast mass with diameter ranging from 7 to 14 cm, and the average size was 11 cm. Histologically, all cases were composed of variably-sized ectatic, thin-walled blood vessels with minimal to no apparent smooth muscle, lined by flat normochromic endothelium without atypia, and diffusely infiltrating the breast stroma. Where present, the lesional vessels infiltrated between and around terminal duct lobular units but not into individual intralobular stroma. Immunohistochemical staining for CD31, CD34, Factor Ⅷ, Fli-1 and D2-40 revealed positive expression in vascular and/or lymphatic endothelial cells. Additionally, the Ki-67 proliferation index was found to be less than 1%. Conclusions: Angiomatosis of the breast is a rare benign vascular lesion. Distinguishing it from low-grade angiosarcoma requires careful consideration of the growth pattern, atypical features, and Ki-67 proliferation index.
目的： 探讨乳腺血管瘤病的临床病理特征及病理诊断。 方法： 收集解放军总医院第七医学中心病理科及北京中医药大学东直门医院病理科2011年1月至2023年12月诊断的共6例乳腺血管瘤病患者，分析其临床病理资料并复习相关文献。 结果： 6例患者均为女性，年龄范围25~62岁，平均年龄46岁。临床常表现为可触及的单侧乳腺肿块，肿瘤最大径7~14 cm，平均11 cm。组织学上，6例均表现为血管、淋巴管弥漫性增生，脉管腔扩张、大小不等、互相吻合、管壁薄，无/极少见平滑肌，内皮细胞扁平、无异型性，病变弥漫性浸润乳腺间质，但不破坏乳腺终末导管小叶单位。CD31、CD34、第Ⅷ因子相关抗原、Fli-1、D2-40等免疫组织化学染色结果显示血管和/或淋巴管内皮细胞阳性，Ki-67阳性指数均<1%。 结论： 乳腺血管瘤病是一种罕见的良性脉管性病变，与低级别血管肉瘤的鉴别需要关注病变生长模式、内皮细胞形态和Ki-67阳性指数。.

Von Willebrand disease (VWD) is an inherited bleeding disorder caused by quantitative and qualitative abnormalities of von Willebrand factor (VWF), a multimeric glycoprotein that is the largest of its kind in plasma and is also found in platelet alpha granules and Weibel-Palade bodies of endothelial cells. VWF plays two roles in hemostasis: (1) primary hemostasis via adhesion of platelet GPIb to subendothelial connective tissue and (2) stabilization of coagulation factor VIII. The pathological classification proposed by the International Society of Thrombosis and Haemostasis (ISTH) in 1994 divided VWF into three major categories based on the results of VWF:RCo, VWF:Ag, and multimer analysis. Recent genetic analysis and molecular and cellular analysis of abnormal VWF have revealed a molecular basis for the dominant inheritance form of VWD.

暂无摘要。

UNASSIGNED: Thrombotic thrombocytopenic purpura, particularly its immune-mediated variant (iTTP), necessitates accurate diagnostic approaches for effective management.
UNASSIGNED: To compare a chemiluminescence immunoassay (CLIA) and an enzyme-linked immunosorbent assay (ELISA) for testing ADAMTS-13 activity and detecting anti-ADAMTS-13 autoantibodies (AAbs) in patients with iTTP.
UNASSIGNED: This study involved 31 paired samples from 12 iTTP patients. ADAMTS-13 activity was measured using the HemosIL AcuStar (Instrumentation Laboratory, CLIA) and Technozym (Technoclone) activity assay (ELISA). The presence of AAbs was assessed using Technozym ADAMTS-13-INH assay (ELISA) and HemosIL AcuStar activity (CLIA) within a Bethesda assay following mixing with normal pool plasma. von Willebrand factor (VWF) multimers were analyzed using the HYDRASYS-2 SCAN system and the HYDRAGEL 5- or 11-VW Multimer kits (Sebia). VWF activity levels were measured with the HemosIL AcuStar VWF:GPIbR on the ACL AcuStar Analyzer (IL).
UNASSIGNED: For ADAMTS-13 activity, a strong linear relationship and no bias between CLIA and ELISA were confirmed (slope = 1.01 [0.91, 1.11], intercept = 0.00 [-0.47, 0]). However, significant discrepancies were found in AAb detection during remission phases with ADAMTS-13 activity between 10% and 50%, with CLIA and ELISA showing significant divergence (P < .001, Cohen\'s g = 0.34). Consistently, VWF multimers and activity levels exhibited significantly different values between remission samples with ADAMTS-13 activity below 50% and above 50%. In longitudinal analysis of patients with multiple iTTP relapses, positivity to CLIA appears to precede ELISA in predicting exacerbations.
UNASSIGNED: While CLIA and ELISA might be interchangeable for assessing ADAMTS-13 activity, they are not equivalent for detecting AAbs, particularly in patients in clinical remission with ADAMTS-13 activity between 10% and 50%.

OBJECTIVE: To investigate the association between periodontitis and cardiometabolic and haemostatic parameters.
METHODS: Between 2014 and 2019, 54 individuals needing full mouth extraction, and 50 control individuals, were recruited for a combined cross-sectional (individuals versus controls) and longitudinal (individuals before and after extraction) study. Periodontitis severity was measured using the periodontal inflamed surface area (PISA). Blood was drawn to measure the haemostatic (Factor VIII, von Willebrand factor [VWF], endogenous thrombin potential, d-dimer, clot lysis time) and cardiovascular risk (C-reactive protein [CRP], lipid profile) parameters, prior to and 12 weeks post-extraction. The results were analysed group-wise.
RESULTS: The mean VWF and CRP levels were higher and the high-density lipoprotein levels were lower in the individuals prior to extraction compared to the controls. The VWF was significantly correlated with the PISA (a 21% unit increase in VWF per 1000 mm2 increase in PISA, 95%CI: 6-36%, p = 0.01). The other analyses were comparable between the individuals and controls, and did not change in the individuals after the extraction.
CONCLUSIONS: VWF levels are associated with periodontitis severity; they do not improve after full-mouth extraction. Severe periodontitis in control individuals does not induce substantial changes in their haemostatic or inflammatory systems.
CONCLUSIONS: Treatment of periodontitis has been shown to improve the cardiometabolic blood profile of patients with established cardiometabolic disease. However, whether periodontitis treatment improves cardiometabolic and haemostatic profiles in people without cardiometabolic disease is uncertain.

The assessment of von Willebrand factor (VWF) multimer distribution, particularly following the implantation of circulatory support devices, is a crucial parameter in hemostasis. Our study aimed to evaluate the semi-automated quantification of VWF multimers using the Sebia Hydrasys analyzer. Our analysis focused on quantifying high molecular weight, intermediate weight, and low molecular weight VWF multimers. Electrophoretic migration was performed using the Hydrasys 2 scan, and interpretation was carried out using densitometric analysis with the Phoresis software. The Hydrasys scan 2 successfully separated all the expected VWF multimer profiles based on the type of von Willebrand disease. The analysis revealed that in patients with circulatory support devices, elevated levels of plasma VWF rendered multimer migration unanalyzable using the methodology recommended by the manufacturer. Therefore, adjustment to a 100 % VWF antigenic level improved gel precision. We also suggest using as a standardized control the Cryocheck™ plasma, and have established reference values. Overall, this semi-automated, standardized, and optimized VWF multimer analysis system allows for an effective assessment of the VWF multimeric profile.

The microvasculature, which makes up the majority of the cardiovascular system, plays a crucial role in the process of thrombosis, with the pathological formation of blood clots inside blood vessels. Since blood microflow conditions significantly influence platelet activation and thrombosis, accurately mimicking the structure of bifurcating microvascular networks and emulating local physiological blood flow conditions are valuable for understanding blood clot formation. In this work, we present an in vitro model for blood clotting in microvessels, focusing on 3D bifurcations that align with Murray\'s law, which guides vascular networks by maintaining a constant wall shear rate throughout. Using these models, we demonstrate that microvascular bifurcations act as sites facilitating thrombus formation compared to straight models. Additionally, by culturing endothelial cells on the luminal surfaces of the models, we show the potential of using our in vitro platforms to recapitulate the initial clotting in diseases involving endothelial dysfunction, such as Thrombotic Thrombocytopenic Purpura.