The impact of aberrant von Willebrand factor-GPIbα interaction on megakaryopoiesis and platelets in humanized type 2B von Willebrand disease model mouse

Application of genetic testing for the diagnosis of von Willebrand disease

von Willebrand disease (VWD) is the most frequent inherited bleeding disorder, with an estimated symptomatic prevalence of 1 per 1000 in the general population. VWD is characterized by defects in the quantity, quality, or multimeric structure of von Willebrand factor (VWF), a glycoprotein being hemostatically essential in circulation. VWD is classified into 3 principal types: low VWF/type 1 with partial quantitative deficiency of VWF, type 3 with virtual absence of VWF, and type 2 with functional abnormalities of VWF, being classified as 2A, 2B, 2M, and 2N. A new VWD type has been officially recognized by the ISTH SSC on von Willebrand factor which has also been discussed by the joint ASH/ISTH/NHF/WFH 2021 guidelines (ie, type 1C), indicating patients with quantitative deficiency due to an enhanced VWF clearance. With the advent of next-generation sequencing technologies, the process of genetic diagnosis has substantially changed and improved accuracy. Therefore, nowadays, patients with type 3 and severe type 1 VWD can benefit from genetic testing as much as type 2 VWD. Specifically, genetic testing can be used to confirm or differentiate a VWD diagnosis, as well as to provide genetic counseling. The focus of this manuscript is to discuss the current knowledge on VWD molecular pathophysiology and the application of genetic testing for VWD diagnosis.

Neuroprotective Effects of Quercetin on Ischemic Stroke: A Literature Review

Ischemic stroke (IS) is characterized by high recurrence and disability; however, its therapies are very limited. As one of the effective methods of treating acute attacks of IS, intravenous thrombolysis has a clear time window. Quercetin, a flavonoid widely found in vegetables and fruits, inhibits immune cells from secreting inflammatory cytokines, thereby reducing platelet aggregation and limiting inflammatory thrombosis. In pre-clinical studies, it has been shown to exhibit neuroprotective effects in patients with ischemic brain injury. However, its specific mechanism of action remains unknown. Therefore, this review aims to use published data to elucidate the potential value of quercetin in patients with ischemic brain injury. This article also reviews the plant sources, pharmacological effects, and metabolic processes of quercetin in vivo, thus focusing on its mechanism in inhibiting immune cell activation and inflammatory thrombosis as well as promoting neuroprotection against ischemic brain injury.