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The newly identified type VII CRISPR–Cas candidate system uses a CRISPR RNA-guided ribonucleoprotein complex formed by Cas5 and Cas7 proteins to target RNA1. However, the RNA cleavage is executed by a dedicated Cas14 nuclease, which is distinct from the effector nucleases of the other CRISPR–Cas systems. Here we report seven cryo-electron microscopy structures of the Cas14-bound interference complex at different functional states. Cas14, a tetrameric protein in solution, is recruited to the Cas5–Cas7 complex in a target RNA-dependent manner. The N-terminal catalytic domain of Cas14 binds a stretch of the substrate RNA for cleavage, whereas the C-terminal domain is primarily responsible for tethering Cas14 to the Cas5–Cas7 complex. The biochemical cleavage assays corroborate the captured functional conformations, revealing that Cas14 binds to different sites on the Cas5–Cas7 complex to execute individual cleavage events. Notably, a plugged-in arginine of Cas7 sandwiched by a C-shaped clamp of C-terminal domain precisely modulates Cas14 binding. More interestingly, target RNA cleavage is altered by a complementary protospacer flanking sequence at the 5′ end, but not at the 3′ end. Altogether, our study elucidates critical molecular details underlying the assembly of the interference complex and substrate cleavage in the type VII CRISPR–Cas system, which may help rational engineering of the type VII CRISPR–Cas system for biotechnological applications.

The interaction between ZnO and Zn-Al spinel oxide is identified to promote the formation of oxygen vacancy and the highly reactive formate, which serves as the active precursor to methoxy and methanol during the hydrogenation process.

IntroductionFamily caregiver’s involvement in advance care planning (ACP) is essential to provide high-quality end-of-life (EOL) care and to ease the surrogate decision-making burden. However, no systematic review has focused on existing ACP interventions involving patients and their families.AimTo systematically summarise current ACP interventions involving patients and their families.MethodsFive English and two Chinese databases were searched from inception to September 2022. The eligible studies were experimental studies describing original data. The Joanna Briggs Institute critical appraisal tools assessed the methodological quality. Narrative synthesis was conducted for data analysis.ResultsIn total, twenty-eight articles were included. Fifteen studies were randomised controlled trials, and the rest 13 studies were quasi-experimental studies. The data synthesis identified: (1) Key intervention components: strategies to promote ACP, ACP discussion and follow-up, as well as the role of family caregivers; (2) Effects on intended outcomes: interventions have shown benefit on completion of ACP actions, while inconsistent findings were found on the process outcomes and quality of EOL care. In addition, a logic model for patient–caregiver dyadic ACP was created, and the underlying mechanisms of action included well-preparation, open discussion and adequate support for plan/action.ConclusionsThis review provides comprehensive evidence about patient–caregiver dyadic ACP, a promising intervention to better prepare for EOL communication and decision-making. A logic model has been mapped to give a preliminary indication for future implementation. More empirical studies are needed to improve this model and culturally adapt it in a real-world setting.

The release of ChatGPT for general use in 2023 by OpenAI has significantly expanded the possible applications of generative artificial intelligence in the healthcare sector, particularly in terms of information retrieval by patients, medical and nursing students, and healthcare personnel.

Chronic bacterial infection, local inflammation, and insufficient angiogenesis contribute to poor healing of diabetic wounds. Here, Cu2O/Pt nanocubes (CPN) are successfully developed with good biocompatibility for treatment of diabetic wounds in rats. The synthesized CPN are characterized using SEM, XPS, and XRD. CPN exhibit triple-enzyme mimetic activity: oxidase-like, peroxidase-like, and catalase-like activities. Moreover, CPN show significant antibacterial activity against Gram-negative and Gram-positive bacteria when combined with low concentration of H2O2, via generation of highly reactive ROS. CPN also exhibit significantly accelerated wound healing in a full-layer deprivation rat model infected by Staphylococcus aureus, which is ascribed to the constant release of copper ions, subsequently activating the VEGF/AKT/ERK1/2 signaling pathway and promoting angiogenesis. CPN are able to catalyze H2O2to generate O2for local hypoxia alleviation. Furthermore, in vivo results indicate that treatment with CPN promotes the expression of transforming growth factor and matrix metalloproteinases, causing enhanced cell proliferation and collagen deposition, as well as extracellular matrix remodeling. In contrast, CPN decrease the expression of proinflammatory cytokines, such as TNF-ɑ and IL-1β, which are induced by bacterial infection and hyperglycemia. These results suggest a novel strategy for the treatment of diabetic wound healing.

Facet engineering of anatase TiO2by controlling the {001} exposure ratio has been the focus of numerous investigations to optimize photocatalytic activity. In particular, an introduction of fluoride ions during the crystal growth has been demonstrated to be very effective and decisive in realizing the facet exposure of the crystals. However, a key role of fluoride ions in stabilizing {001} exposure and improving subsequent photocatalytic activity of anatase TiO2remains unclear up to date. Herein, a controlled thickness of anatase TiO2nanosheets has been realized by introducing different amounts of ethanol into a HF acid-assisted hydrothermal reaction. The thinnest nanosheets with a thickness of ∼2.9 nm were evaluated to have the highest H2production rate of 41.04 mmol·h–1·g–1under ultraviolet light irradiation, and the corresponding quantum efficiency was determined to be 41.6% (λ = 365 nm). Moreover, it is proved for the first time that fluoride ions are bonded with Ti vacancies on {001} facets, and such defects are crucial for stabilizing the ultrathin nanosheets and improving their electron–hole separation, therefore leading to a highly efficient photocatalytic activity. The findings offer an opportunity to engineer facets and functionality of anatase TiO2by controlling surface defects.

Leber congenital amaurosis type 10 is a severe retinal dystrophy caused by mutations in the CEP290 gene1,2. We developed EDIT-101, a candidate genome-editing therapeutic, to remove the aberrant splice donor created by the IVS26 mutation in the CEP290 gene and restore normal CEP290 expression. Key to this therapeutic, we identified a pair of Staphylococcus aureusCas9 guide RNAs that were highly active and specific to the human CEP290 target sequence. In vitro experiments in human cells and retinal explants demonstrated the molecular mechanism of action and nuclease specificity. Subretinal delivery of EDIT-101 in humanized CEP290 mice showed rapid and sustained CEP290 gene editing. A comparable surrogate non-human primate (NHP) vector also achieved productive editing of the NHP CEP290 gene at levels that met the target therapeutic threshold, and demonstrated the ability of CRISPR/Cas9 to edit somatic primate cells in vivo. These results support further development of EDIT-101 for LCA10 and additional CRISPR-based medicines for other inherited retinal disorders.

Gelatin methacryloyl (GelMA), a photocurable hydrogel, is widely used in 3D culture, particularly in 3D bioprinting, due to its high biocompatibility, tunable physicochemical properties, and excellent formability. However, as the properties and performances of GelMA vary under different synthetic conditions, there is a lack of standardization, leading to conflicting results. In this study, a uniform standard is established to understand and enhance GelMA applications. First, the basic concept of GelMA and the density of the molecular network (DMN) are defined. Second, two properties, degrees of substitution and ratio of solid content, as the main measurable parameters determining the DMN are used. Third, the mechanisms and relationships between DMN and its performance in various applications in terms of porosity, viscosity, formability, mechanical strength, swelling, biodegradation, and cytocompatibility are theoretically explained. The main questions that are answered: what does performance mean, why is it important, how to optimize the basic parameters to improve the performance, and how to characterize it reasonably and accurately? Finally, it is hoped that this knowledge will eliminate the need for researchers to conduct tedious and repetitive pre‐experiments, enable easy communication for achievements between groups under the same standard, and fully explore the potential of the GelMA hydrogel. Gelatin methacryloyl (GelMA), a popular hydrogel in tissue engineering, lacks standardization leading to conflicting results. The research establishes uniform standards to understand and make better use of it. By enhancing GelMA's properties through improved understanding and standardizing its parameters, future studies may become more consistent and reproducible, ultimately leading to more effective tissue engineering and regenerative medical therapies.

De Dreuzy: Editas Medicine Inc.: Employment, Equity Ownership. Heath:Editas Medicine Inc.: Employment, Equity Ownership. Zuris:Editas Medicine Inc.: Employment, Equity Ownership. Sousa:Editas Medicine Inc.: Employment, Research Funding. Viswanathan:Editas Medicine Inc.: Employment, Equity Ownership. Scott:Editas Medicine Inc.: Employment, Equity Ownership. Da Silva:Editas Medicine Inc.: Employment, Equity Ownership. Ta:Editas Medicine Inc.: Employment, Equity Ownership. Capehart:Editas Medicine Inc.: Equity Ownership. Wang:Editas Medicine Inc.: Employment, Equity Ownership. Fernandez:Editas Medicine Inc.: Employment, Equity Ownership. Myer:Editas Medicine Inc.: Employment, Equity Ownership. Albright:Editas Medicine Inc.: Employment, Equity Ownership. Wilson:Editas Medicine Inc.: Employment, Equity Ownership. Teixeira:Editas Medicine Inc.: Employment, Equity Ownership. Chang:Editas Medicine Inc.: Employment, Equity Ownership.

Sickle cell disease (SCD) is an inherited blood disorder affecting approximately 100,000 individuals in the United States. Fetal hemoglobin (HbF) is a major modifier of SCD severity. Studies showed that individuals with compound heterozygosity for sickle hemoglobin (HbS) and hereditary persistence of fetal hemoglobin (HPFH) that expressed approximately 30% HbF did not show features of SCD. Therefore, we are developing EDIT-301, an experimental autologous cell therapy comprising CD34+ cells genetically modified using a Cas12a RNP (ribonucleoprotein) to promote HbF expression to treat SCD.

Chang: Editas Medicine Inc.: Employment, Equity Ownership. Sanchez:Editas Medicine Inc.: Employment, Equity Ownership. Heath:Editas Medicine Inc.: Employment, Equity Ownership. deDreuzy:Editas Medicine Inc.: Employment, Equity Ownership. Haskett:Editas Medicine Inc.: Employment, Equity Ownership. Vogelaar:Editas Medicine Inc.: Employment. Gogi:Editas Medicine Inc.: Employment, Equity Ownership. Da Silva:Editas Medicine Inc.: Employment, Equity Ownership. Wang:Editas Medicine Inc.: Employment, Equity Ownership. Sadowski:Editas Medicine Inc.: Employment, Equity Ownership. Gotta:Editas Medicine Inc.: Employment, Equity Ownership. Siwak:Editas Medicine Inc.: Employment, Equity Ownership. Viswanathan:Editas Medicine Inc.: Employment, Equity Ownership. Loveluck:Editas Medicine Inc.: Employment, Equity Ownership. Chao:Editas Medicine Inc.: Employment, Equity Ownership. Tillotson:Editas Medicine Inc.: Employment, Equity Ownership. Chalishazar:Editas Medicine Inc.: Employment, Equity Ownership. Dass:Editas Medicine Inc.: Employment, Equity Ownership. Ta:Editas Medicine Inc.: Employment, Equity Ownership. Brennan:Editas Medicine Inc.: Employment, Equity Ownership. Tabbaa:Editas Medicine Inc.: Employment, Equity Ownership. Marco:Editas Medicine Inc.: Employment, Equity Ownership. Zuris:Editas Medicine Inc.: Employment, Equity Ownership. Reyon:Editas Medicine Inc.: Employment, Equity Ownership. Isik:Editas Medicine Inc.: Employment, Equity Ownership. Friedland:Editas Medicine Inc.: Employment, Equity Ownership. Ta:Editas Medicine Inc.: Employment, Equity Ownership. Harbinski:Editas Medicine Inc.: Employment, Equity Ownership. Giannoukos:Editas Medicine Inc.: Employment, Equity Ownership. Teixeira:Editas Medicine Inc.: Employment, Equity Ownership. Wilson:Editas Medicine Inc.: Employment, Equity Ownership. Albright:Editas Medicine Inc.: Employment, Equity Ownership. Jiang:Editas Medicine Inc.: Employment, Equity Ownership.