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Hemorrhage is one of the leading preventable causes of death associated with trauma, which is often complicated by wound infection. Current hemostatic materials are not ideal and lack antimicrobial properties needed for infection prevention. Here, we tested the feasibility for 6-chlorodopamine-functionalized gelatin (GDC) nanoparticles to function as a hemostatic powder with strong tissue adhesion and antibacterial properties. 6-Chlorodopamine contains a catechol sidechain that is further modified with an electron withdrawing chlorine atom, and provides strong tissue adhesion and antimicrobial property. These gelatin nanoparticles are not covalently crosslinked, which enablde them to rapidly transition into an adhesive film when hydrated with an aqueous solution or blood. The chlorination of catechol significantly increased structural integrity, interfacial bonding to tissue surface, and the rate of film formation. Additionally, GDC nanoparticles are noncytotoxic and nonhemolytic, and effectively killed Gram-positive (Staphylococcus epidermidis, Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. Finally, GDC nanoparticles achieved significantly faster hemostasis and reduced blood loss when compared to a commercial fibrin glue, Tisseel, in tail transection and liver hemorrhage models performed in mice. These findings highlight the potential of GDC nanoparticle as a versatile, multifunctional hemostatic agent capable of both rapid hemorrhage control and infection prevention. 

An SHAM-containing adhesive was combined with PVDF to form a novel structural adhesive. SHAM provides interfacial bonding capability while PVDF increases cohesion through hydrogen bonding with the adhesive polymer backbone. 

Agrobacterium-mediated transformation is an essential tool for functional genomics studies and crop improvements. Recently developed ternary vector systems, which consist of a T-DNA vector and a compatible virulence (vir) gene helper plasmid (ternary helper), demonstrated that including an additionalvirgene helper plasmid into disarmedAgrobacteriumstrains significantly improves T-DNA delivery efficiency, enhancing plant transformation. Here, we report the development of a new ternary helper and thymidine auxotrophicAgrobacteriumstrains to boostAgrobacterium-mediated plant transformation efficiency. AuxotrophicAgrobacteriumstrains are useful in reducingAgrobacteriumovergrowth after the co-cultivation period because they can be easily removed from the explants due to their dependence on essential nutrient supplementation. We generated thymidine auxotrophic strains from publicAgrobacteriumstrains EHA101, EHA105, EHA105D, and LBA4404. These strains exhibited thymidine-dependent growth in the bacterial medium, and transientGUSexpression assay using Arabidopsis seedlings showed that they retain similar T-DNA transfer capability as their original strains. Auxotrophic strains EHA105Thy- and LBA4404T1 were tested for maize B104 immature embryo transformation using our rapid transformation method, and both strains demonstrated comparable transformation frequencies to the control strain LBA4404Thy-. In addition, our new ternary helper pKL2299A, which carries thevirAgene from pTiBo542 in addition to othervirgene operons (virG,virB,virC,virD,virE, andvirJ), demonstrated consistently improved maize B104 immature embryo transformation frequencies compared to the original version of pKL2299 (33.3% vs 25.6%, respectively). Therefore, our improvedAgrobacteriumsystem, including auxotrophic disarmedAgrobacteriumstrains and a new ternary helper plasmid, can be useful for enhancing plant transformation and genome editing applications. 

Efficient genetic transformation is a prerequisite for rapid gene functional analyses and crop trait improvements. We recently demonstrated that new T-DNA binary vectors with NptII/G418 selection and a compatible helper plasmid can efficiently transform maize inbred B104 using our rapid Agrobacterium-mediated transformation method. In this work, we implemented the non-integrating Wuschel2 (Wus2) T-DNA vector method for Agrobacterium-mediated B104 transformation and tested its potential for recalcitrant inbred B73 transformation and gene editing. The non-integrating Wus2 (NIW) T-DNA vector-assisted transformation method uses two Agrobacterium strains: one carrying a gene-of-interest (GOI) construct and the other providing an NIW construct. To monitor Wus2 co-integration into the maize genome, we combined the maize Wus2 expression cassette driven by a strong constitutive promoter with a new visible marker RUBY, which produces the purple pigment betalain. As a GOI construct, we used a previously tested CRISPR-Cas9 construct pKL2359 for Glossy2 gene mutagenesis. When both GOI and NIW constructs were delivered by LBA4404Thy- strain, B104 transformation frequency was significantly enhanced by about two-fold (10% vs. 18.8%). Importantly, we were able to transform a recalcitrant inbred B73 using the NIW-assisted transformation method and obtained three transgene-free edited plants by omitting the selection agent G418. These results suggest that NIW-assisted transformation can improve maize B104 transformation frequency and provide a novel option for CRISPR technology for transgene-free genome editing.