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Cardiovascular disease is the leading cause of global mortality, with anticoagulant therapy being the main prevention and treatment strategy. Recombinant hirudin (r-hirudin) is a direct thrombin inhibitor that can potentially prevent thrombosis via subcutaneous (SC) and intravenous (IV) administration, but there is a risk of haemorrhage via SC and IV. Thus, microneedle (MN) provides painless and sanitary alternatives to syringes and oral administration. However, the current technological process for the micro mould is complicated and expensive. The micro mould obtained via three-dimensional (3D) printing is expected to save time and cost, as well as provide a diverse range of MNs. Therefore, we explored a method for MNs array model production based on 3D printing and translate it to micro mould that can be used for fabrication of dissolving MNs patch. The results show that r-hirudin-loaded and hyaluronic acid (HA)-based MNs can achieve transdermal drug delivery and exhibit significant potential in the prevention of thromboembolic disease without bleeding in animal models. These results indicate that based on 3D printing technology, MNs combined with r-hirudin are expected to achieve diverse customizable MNs and thus realize personalized transdermal anticoagulant delivery for minimally invasive and long-term treatment of thrombotic disease.

Summary: Septins are GTP-binding proteins involved in several membrane remodeling mechanisms. They associate with membranes, presumably using a polybasic domain (PB1) that interacts with phosphoinositides (PIs). Membrane-bound septins assemble into microscopic structures that regulate membrane shape. How septins interact with PIs and then assemble and shape membranes is poorly understood. Here, we found that septin 9 has a second polybasic domain (PB2) conserved in the human septin family. Similar to PB1, PB2 binds specifically to PIs, and both domains are critical for septin filament formation. However, septin 9 membrane association is not dependent on these PB domains, but on putative PB-adjacent amphipathic helices. The presence of PB domains guarantees protein enrichment in PI-contained membranes, which is critical for PI-enriched organelles. In particular, we found that septin 9 PB domains control the assembly and functionality of the Golgi apparatus. Our findings offer further insight into the role of septins in organelle morphology. : Membrane Architecture; Molecular Interaction; Cell Biology; Functional Aspects of Cell Biology Subject Areas: Membrane Architecture, Molecular Interaction, Cell Biology, Functional Aspects of Cell Biology

The COVID-19 disease caused by the SARS-CoV-2 virus is a health crisis worldwide. While developing novel drugs and vaccines is long, repurposing existing drugs against COVID-19 can yield treatments with known preclinical, pharmacokinetic, pharmacodynamic, and toxicity profiles, which can rapidly enter clinical trials. In this study, we present a novel network-based drug repurposing platform to identify candidates for the treatment of COVID-19. At the time of the initial outbreak, knowledge about SARS-CoV-2 was lacking, but based on its similarity with other viruses, we sought to identify repurposing candidates to be tested rapidly at the clinical or preclinical levels. We first analyzed the genome sequence of SARS-CoV-2 and confirmed SARS as the closest virus by genome similarity, followed by MERS and other human coronaviruses. Using text mining and database searches, we obtained 34 COVID-19-related genes to seed the construction of a molecular network where our module detection and drug prioritization algorithms identified 24 disease-related human pathways, five modules, and 78 drugs to repurpose. Based on clinical knowledge, we re-prioritized 30 potentially repurposable drugs against COVID-19 (including pseudoephedrine, andrographolide, chloroquine, abacavir, and thalidomide). Our work shows how in silico repurposing analyses can yield testable candidates to accelerate the response to novel disease outbreaks.

In this study, Continuous Discontinuous Element Method (CDEM) was employed to analyze the failure of concrete slab under drop-hammer impact at the mesoscopic level. Initially, simulation models of the impact system were established, and concrete slab models, including three-dimensional random aggregates, were generated. Mesoscopic simulations of concrete failure were then conducted by considering different variables, such as impact energy, slab size and the number of hammerheads. Corresponding drop hammer tests were used to validate the simulation results. Furthermore, an energy conversion formula for the dynamic failure of concrete slabs was derived, and the energy conversion process within the impact system was analyzed. The study also revealed the dynamic failure mechanisms of concrete slabs under various impact conditions. The research demonstrates that the simulation results are generally consistent with the impact tests. CDEM effectively investigates the impact characteristic and the energy conversion process of concrete slab failure. Under varying impact energies, slab sizes and hammerhead numbers, distinct differences in the failure characteristics of concrete-slab structure were observed. Increased impact energy accelerates the failure of concrete slabs, whereas larger concrete slab sizes inhibit crack propagation. The number of impact heads determines the initial crack position and its propagation path within the concrete slab. Moreover, the energy conversion process of the impact system significantly influences the failure behavior of the concrete slab. The effect of slab size on the energy utilization rate is greater than those of hammerhead number and impact speed.